Immunohistochemical Assessment of Mast Cells and Small Blood Vessels in Dentigerous Cyst, Odontogenic Keratocyst, and Periapical Cyst.

PubMed

Kouhsoltani, Maryam; Moradzadeh Khiavi, Monir; Jamali, Golshan; Farnia, Samira

2015-12-01

The aim of this study was to verify the density of mast cells (MCs) and microvessels in odontogenic cysts. Furthermore, the correlation between MCs and microvessels was evaluated to assess the contribution of MCs to angiogenesis and growth of odontogenic cysts. This approach may be a basis for the development of future pharmaceuticals addressed to MCs performance to manage odontogenic cysts. To our knowledge, no study investigating the correlation between MCs and microvessels has been performed to date. 60 cases of odontogenic cysts consisting of 20 radicular cysts (RCs), 20 odontogenic keratocysts (OKCs) and 20 dentigerous cysts (DCs) were included in this study. Five high power fields in superficial connective tissue and five high power fields in deep connective tissue were counted for each sample. Moreover, a total mean of ten fields was calculated. RC showed the highest mean numbers of MCs and microvessels (p<0.05). The subepithelial zones of all cysts contained more MCs and microvessels compared to the deeper zones. A statistically significant correlation between the numbers of MCs and microvessels was not observed (r=0.00, p=0.49). Although the number of MCs was not significantly associated with microvessels, these cells may be related to the growth of odontogenic lesions, particularly RCs. Further studies on the in vivo functions of MCs will make the concept more clear.

[The expression of IDH1 (R132H) is positively correlated with cell proliferation and angiogenesis in glioma samples].

PubMed

Shi, Jiankuan; Zhao, Yuanlin; Yuan, Yuan; Wang, Chao; Xie, Zhonglin; Gao, Xing; Xiao, Liming; Ye, Jing

2016-03-01

To explore the correlations of the expression of mutant isocitrate dehydrogenase (IDH1) (R132H) protein with angiogenesis and cell proliferation in glioma. We performed polymerase chain reaction-based IDH gene mutation screening in 385 glioma samples, and the subcellular localization and expression levels of IDH1 (R132H) was examined by immunohistochemistry (IHC). Ki-67 labeling index was introduced to determine the proliferation of glioma cells, and the microvessel density was measured through CD34 staining. Statistical analyses were performed to show the correlations of IDH1 mutation with cell proliferation and microvessel density. The mutant rates of IDH1 were about 50%-60% in grade II-III gliomas and secondary glioblastomas, which were significantly higher than those in pilocytic astrocytoma (grade I) and primary glioblastoma (grade IV). Moreover, the level of IDH1 (R132H) protein was positively correlated with Ki-67 labeling index and microvessel density. IDH mutation was common in grade II-III glioma and secondary glioblastoma, and the mutant IDH1 (R132H) might play a critical role in the cell proliferation and angiogenesis of glioma.

Variability in sublingual microvessel density and flow measurements in healthy volunteers.

PubMed

Hubble, Sheena M A; Kyte, Hayley L; Gooding, Kim; Shore, Angela C

2009-02-01

As sublingual microvascular indices are increasingly heralded as new resuscitation end-points, better population data are required to power clinical studies. This paper describes improved methods to quantify sublingual microvessel flow and density in images obtained by sidestream dark field (SDF) technology in healthy volunteers, including vessels under 10 microm in diameter. Measurements of sublingual capillary density and flow were obtained by recording three 15-second images in 20 healthy volunteers over three days. Two independent observers quantified capillary density by using two methods: total vessel length (mm/mm2) and counting (number/mm). Both intraoral and temporal variabilities within subject and observer reproducibilities were determined by using coefficients of variability and reproducibility indices. For small (1-10 microm), medium (11-20 microm), and large (21-50 microm) diameter, mean vessel density with standard deviations (SDs) in volunteers was 21.3(+/- 4.9), 5.2 (+/- 1.2), and 2.7 (+/- 0.9) mm/mm2, respectively. Also, 94.0 +/- 1.4% of small vessels, 94.5 +/- 1.4% of medium vessels, and 94.5+/- 4.0% of large vessels had continuous perfusion. Within subjects, the means of all measurements over three days varied less than 13, 22, and 35% in small, medium, and large vessels, respectively. Interobserver reproducibility was good, especially for capillary (1-10 microm) density and flow measurements. Our methods of microvessel flow and density quantification have low observer variability and confirm the stability of microcirculatory measurements over time. These results facilitate the development of SDF-acquired sublingual microvascular indices as feasible microperfusion markers in shock resuscitation.

Defining the Phosphodiesterase Superfamily Members in Rat Brain Microvessels

PubMed Central

2011-01-01

Eleven phosphodiesterase (PDE) families are known, each having several different isoforms and splice variants. Recent evidence indicates that expression of individual PDE family members is tissue-specific. Little is known concerning detailed PDE component expression in brain microvessels where the blood-brain-barrier and the local cerebral blood flow are thought to be regulated by PDEs. The present study attempted to identify PDE family members that are expressed in brain microvessels. Adult male F344 rats were sacrificed and blocks of the cerebral cortex and infratentorial areas were dissected. Microvessels were isolated using a filtration method, and total RNA was extracted. RNA quality and quantity were determined using an Agilent bioanalyzer. The isolated cortical and infratentorial microvessel total RNA amounts were 2720 ± 750 ng (n = 2) and 250 ± 40 ng (n = 2), respectively. Microarrays with 22 000 transcripts demonstrated that there were 16 PDE transcripts in the PDE superfamily, exhibiting quantifiable density in the microvessels. An additional immunofluorescent study verified that PDE4D (cAMP-specific) and PDE5A (cGMP-specific) were colocalized with RECA-1 (an endothelial marker) in the cerebral cortex using both F344 rats and Sprague–Dawley rats (n = 3–6/strain). In addition, PDE4D and PDE5A were found to be colocalized with alpha-smooth muscle actin which delineates cerebral arteries and arterioles as well as pericytes. In conclusion, a filtration method followed by microarray analyses allows PDE components to be identified in brain microvessels, and confirmed that PDE4D and PDE5A are the primary forms expressed in rat brain microvessels. PMID:22860158

Prognostic significance of microvessel density and mast cell density for the survival of Thai patients with primary colorectal cancer.

PubMed

Yodavudh, Sirisanpang; Tangjitgamol, Siriwan; Puangsa-art, Supalarp

2008-05-01

Angiogenesis has been found to be a reliable prognostic indicator for several types of malignancies. In colorectal cancer, however there has been controversy as to whether there is a correlation between this feature and the tumors' behavior. Determine the correlation between microvessel density (MVD) and mast cell density (MCD) in order to evaluate these factors in terms of their prognostic relevance for primary colorectal carcinoma in Thai patients. One hundred and thirty colorectal carcinoma patients diagnosed between January 2002 and December 2004 were identified. Eleven patients were excluded from the present study due to recurrence of colorectal carcinoma in eight cases whereas pathologic blocks were not found in three cases. One hundred and nineteen patients met all inclusion criteria and were included in the present study. Representative paraffin sections obtained by the tissue micro-array technique (9 x 5 arrays per slide) from areas of highest vascular density (hot spots) were prepared. Sections were immuno-stained by monoclonal anti CD 31 for microvessel and antibody mast cell tryptase for mast cell detections, respectively. Three readings at different periods of time under a microscopic examination of high power magnification were examined by a pathologist who was blinded to clinical data. The highest microvessel and mast cell counts were recorded as MVD and MCD. Patients were then divided into groups of high and low MVD and high and low MCD by median values (20.5 and 14.5, respectively). Overall survival of the patients in each group was estimated by the Kaplan-Meier Method while a multivariate Cox regression backward stepwise analysis was employed to find out independent prognostic factors. Significant positive correlation was found to exist between MVD and MCD in the hot spots (R = 0.697, p < 0.0001). Regarding their prognostic role, patients with tumors of low MVD (hypovascular) and low MCD (low mast cell counts) had significantly longer survival rates than those with hypervascular and high mast cell counts (p < 0.0001). The Multivariate Cox hazard showed that MVD and distance metastasis of cancer were independent poor prognostic factors to survival (p = 0.036 and p = 0.024, respectively). The patients with high MVD (hypervascular) tumors and with presence of distant metastasis had 1.9 and 2.5 times higher death rates than the corresponding hypovascular and non-metastatic groups, respectively during the period from January 2002 to September 2007. Assessment of microvessel density in the invasive front of primary colorectal carcinoma could serve as useful prognosis tool of primary colorectal carcinoma in Thai patients.

Visible light optical spectroscopy is sensitive to neovascularization in the dysplastic cervix

NASA Astrophysics Data System (ADS)

Chang, Vivide Tuan-Chyan; Bean, Sarah M.; Cartwright, Peter S.; Ramanujam, Nirmala

2010-09-01

Neovascularization in cervical intraepithelial neoplasia (CIN) is studied because it is the precursor to the third most common female cancer worldwide. Diffuse reflectance from 450-600 nm was collected from 46 patients (76 sites) undergoing colposcopy at Duke University Medical Center. Total hemoglobin, derived using an inverse Monte Carlo model, significantly increased in CIN 2+ (N=12) versus CIN 1 (N=16) and normal tissues (N=48) combined with P<0.004. Immunohistochemistry using monoclonal anti-CD34 was used to quantify microvessel density to validate the increased hemoglobin content. Biopsies from 51 sites were stained, and up to three hot spots per slide were selected for microvessel quantification by two observers. Similar to the optical study results, microvessel density was significantly increased in CIN 2+ (N=16) versus CIN 1 (N=21) and normal tissue (N=14) combined with P<0.007. Total vessel density, however, was not significantly associated with dysplastic grade. Hence, our quantitative optical spectroscopy system is primarily sensitive to dysplastic neovascularization immediately beneath the basement membrane, with minimal confounding from vascularity inherent in the normal stromal environment. This tool could have potential for in vivo applications in screening for cervical cancer, prognostics, and monitoring of antiangiogenic effects in chemoprevention therapies.

Retinal Microvascular Network and Microcirculation Assessments in High Myopia.

PubMed

Li, Min; Yang, Ye; Jiang, Hong; Gregori, Giovanni; Roisman, Luiz; Zheng, Fang; Ke, Bilian; Qu, Dongyi; Wang, Jianhua

2017-02-01

To investigate the changes of the retinal microvascular network and microcirculation in high myopia. A cross-sectional, matched, comparative clinical study. Twenty eyes of 20 subjects with nonpathological high myopia (28 ± 5 years of age) with a refractive error of -6.31 ± 1.23 D (mean ± SD) and 20 eyes of 20 age- and sex-matched control subjects (30 ± 6 years of age) with a refractive error of -1.40 ± 1.00 D were recruited. Optical coherence tomography angiography (OCTA) was used to image the retinal microvascular network, which was later quantified by fractal analysis (box counting [D box ], representing vessel density) in both superficial and deep vascular plexuses. The Retinal Function Imager was used to image the retinal microvessel blood flow velocity (BFV). The BFV and microvascular density in the myopia group were corrected for ocular magnification using Bennett's formula. The density of both superficial and deep microvascular plexuses was significantly decreased in the myopia group in comparison to the controls (P < .05). The decrease of the microvessel density of the annular zone (0.6-2.5 mm), measured as D box , was 2.1% and 2.9% in the superficial and deep vascular plexuses, respectively. Microvessel density reached a plateau from 0.5 mm to 1.25 mm from the fovea in both groups, but that in the myopic group was about 3% lower than the control group. No significant differences were detected between the groups in retinal microvascular BFV in either arterioles or venules (P > .05). Microvascular densities in both superficial (r = -0.45, P = .047) and deep (r = -0.54, P = .01) vascular plexuses were negatively correlated with the axial lengths in the myopic eye. No correlations were observed between BFV and vessel density (P > .05). Retinal microvascular decrease was observed in the high myopia subjects, whereas the retinal microvessel BFV remained unchanged. The retinal microvascular network alteration may be attributed to ocular elongation that occurs with the progression of myopia. The novel quantitative analyses of the retinal microvasculature may help to characterize the underlying pathophysiology of myopia and enable early detection and prevention of myopic retinopathy. Copyright © 2016 Elsevier Inc. All rights reserved.

Endoglin (CD105) expression on microvessel endothelial cells in juvenile nasopharyngeal angiofibroma: tissue microarray analysis and association with prognostic significance.

PubMed

Wang, Jing-Jing; Sun, Xi-Cai; Hu, Li; Liu, Zhuo-Fu; Yu, Hua-Peng; Li, Han; Wang, Shu-Yi; Wang, De-Hui

2013-12-01

The purpose of this study was to examine endoglin (CD105) expression on microvessel endothelial cells (ECs) in juvenile nasopharyngeal angiofibroma (JNA) and its relationship with recurrence. Immunohistochemistry was performed to detect CD105 expression in a tissue microarray from 70 patients with JNA. Correlation between CD105 expression on microvessel ECs and clinicopathological features, as well as tumor recurrence, were analyzed. Immunohistochemistry revealed CD105 expression on ECs but not in stroma of patients with JNA. Chi-square analysis indicated CD105-based microvessel density (MVD) was correlated with JNA recurrence (p = .013). Univariate and multivariate analyses determined that MVD was a significant predictor of time to recurrence (p = .009). The CD105-based MVD was better for predicting disease recurrence (AUROC: 0.673; p = .036) than other clinicopathological features. MVD is a useful predictor for poor prognosis of patients with JNA after curative resection. Angiogenesis, which may play an important role in the occurrence and development of JNA, is therefore a potential therapeutic target for JNA. Copyright © 2013 Wiley Periodicals, Inc., A Wiley Company.

Effects of a herbal medicine, Hippophae rhamnoides, on cardiovascular functions and coronary microvessels in the spontaneously hypertensive stroke-prone rat.

PubMed

Koyama, Tomiyasu; Taka, Akira; Togashi, Hiroko

2009-01-01

The dry fruits of Hippophae rhamnoides (so-called "Saji" or "Sea buckthorn") are used in China as a herbal medicine. The present work studied the effects on microvessels in the left ventricular wall, hematological parameters, cardiovascular performance and plasma constituents in spontaneously hypertensive stroke-prone rats (SHRSP/EZO) treated with Hippophae for 60 days. Analyses showed that the powder made of dry Hippophae fruits contains the vitamins C, B1, B2 and E, provitamin A, rutin, serotonin, cytosterol, selenium and zinc, among other constituents. The experimental rats were fed ad libitum with blocks of rat chow supplemented with Hippophae powder at a concentration of 0.7 g/kg in rat powder chow, while control rats were unsupplemented chow. The mean arterial blood pressure, heart rate, total plasma cholesterol, triglycerides, and glycated hemoglobin were significantly decreased by the Hippophae treatment. The arteriolar capillary portions of microvessels expressing alkaline phosphatase decreased, but there was a trend for an increase in the total capillary density. It was concluded that Hippophae fruits improved the metabolic processes accompanied by reduction of hypertensive stress on the ventricular microvessels.

Thrombin Induces Inositol Trisphosphate-Mediated Spatially Extensive Responses in Lung Microvessels.

PubMed

Escue, Rachel; Kandasamy, Kathirvel; Parthasarathi, Kaushik

2017-04-01

Activation of plasma membrane receptors initiates compartmentalized second messenger signaling. Whether this compartmentalization facilitates the preferential intercellular diffusion of specific second messengers is unclear. Toward this, the receptor-mediated agonist, thrombin, was instilled into microvessels in a restricted region of isolated blood-perfused mouse lungs. Subsequently, the thrombin-induced increase in endothelial F-actin was determined using confocal fluorescence microscopy. Increased F-actin was evident in microvessels directly treated with thrombin and in those located in adjoining thrombin-free regions. This increase was abrogated by inhibiting inositol trisphosphate-mediated calcium release with Xestospongin C (XeC). XeC also inhibited the thrombin-induced increase in the amplitude of endothelial cytosolic Ca 2+ oscillations. Instillation of thrombin and XeC into adjacent restricted regions increased F-actin in microvessels in the thrombin-treated and adjacent regions but not in those in the XeC-treated region. Thus, inositol trisphosphate, and not calcium, diffused interendothelially to the spatially remote thrombin-free microvessels. Thus, activation of plasma membrane receptors increased the ambit of inflammatory responses via a second messenger different from that used by stimuli that induce cell-wide increases in second messengers. Thrombin however failed to induce the spatially extensive response in microvessels of mice lacking endothelial connexin43, suggesting a role for connexin43 gap junctions. Compartmental second messenger signaling and interendothelial communication define the specific second messenger involved in exacerbating proinflammatory responses to receptor-mediated agonists. Copyright © 2017 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

[Study on the relationship between intratumor microvessel density and neck metastasis of laryngeal and hypopharyngeal squamous cell carcinomas].

PubMed

Yu, Z; Wang, T; Luan, X

1997-06-01

Sixty-one laryngeal and hypopharyngeal squamous cell, carcinoma (LC, HPC) tissue slides were immunochemically stained using LSAB method to study epithelium cells. The results demonstrated that (1) intratumor microvessel density (ITMD) in LC and HPC group was higher than that of the benign group (P < 0.05). ITMD was higher in the subgroup of LC and HPC with positive lymph node positive than that with negative lymph nodes. This result suggest that ITMD is relevant not only to the nature of the tumor, but also to lymph node metastasis. The level of ITMD is an important predictive sign of metastasis. (2) The relationship between ITMD and the clinical staging had no statistic significance (P > 0.05). (3) The analysis on the relationship between ITMD and pathologic differentiation indicated that the level of ITMD raised gradually with the lowering of the pathologic differentiation.

Three-dimensional motion and deformation of a red blood cell in bifurcated microvessels

NASA Astrophysics Data System (ADS)

Ye, Ting; Peng, Lina; Li, Yu

2018-02-01

Microvessels are generally not simple straight tubes, but rather they continually bifurcate (namely, diverging bifurcation) and merge with other microvessels (namely, converging bifurcation). This paper presents a simulation study on the three-dimensional motion and deformation of a red blood cell (RBC) in a bifurcated microvessel with both diverging and converging bifurcations. The motion of the fluids inside and outside of the RBC is modeled by smooth dissipative particle dynamics. The RBC membrane is modeled as a triangular network, having the ability to not only resist the stretching and bending deformations, but also to conserve the RBC volume and surface area. The bifurcation configurations have been studied, including the bifurcated angle and the branch diameter, as well as the RBC properties, including the initial shape, shear modulus, and bending modulus. The simulation results show that the RBC deformation can be divided into five stages, when the RBC flows through a diverging-converging bifurcated microvessel. In these five stages, the RBCs have similar deformation trends but different deformation indices, subject to different bifurcation configurations or different RBC properties. If the shear modulus is large enough, the RBC membrane presents several folds; if the bending modulus is large enough, the RBC loses the symmetry completely with the long shape. These results are helpful in understanding the motion and deformation of healthy or unhealthy cells in blood microcirculation.

Overexpression of c-kit(CD117), relevant with microvessel density, is an independent survival prognostic factor for patients with HBV-related hepatocellular carcinoma.

PubMed

Yan, Weiwei; Zhu, Zhenyu; Pan, Fei; Huang, Ang; Dai, Guang-Hai

2018-01-01

To explore new biomarkers for indicating the recurrence and prognosis in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients after tumor resection, we investigated the expression and prognostic value of c-kit(CD117) in HBV-related HCC. Immunohistochemistry was used to estimate the expression of c-kit(CD117) and CD34 in the liver cancer tissues. The correlations between the expression of these biomarkers and the clinicopathologic characteristics were analyzed. The positive rate of c-kit(CD117) expression in 206 HCC cases was 48.1%, and c-kit expression was significantly related with CD34-positive microvessel density. CD34-microvessel density numbers were much higher in c-kit(+) HCC tissues than in c-kit(-) HCC tissues (44.13±17.01 vs 26.87±13.16, P =0.003). The expression of c-kit was significantly higher in patients with Edmondson grade III-IV ( P <0.001) and TNM stage III ( P <0.001). Moreover, Kaplan-Meier survival analysis showed that c-kit ( P <0.001) expression was correlated with reduced disease-free survival (DFS). Multivariate analysis identified c-kit as an independent poor prognostic factor of DFS in HCC patients ( P <0.001). Increased c-kit expression could be considered as an independent unfavorable prognostic factor for predicting DFS in HBV-related HCC patients after surgery. These results could be used to identify patients at a higher risk of early tumor recurrence and poor prognosis.

Characterization of nerve and microvessel damage and recovery in type 1 diabetic mice after permanent femoral artery ligation.

PubMed

Lozeron, Pierre; Mantsounga, Chris S; Broqueres-You, Dong; Dohan, Anthony; Polivka, Marc; Deroide, Nicolas; Silvestre, Jean-Sébastien; Kubis, Nathalie; Lévy, Bernard I

2015-09-01

Neuropathy is the most common complication of the peripheral nervous system during the progression of diabetes. The pathophysiology is unclear but may involve microangiopathy, reduced endoneurial blood flow, and tissue ischemia. We used a mouse model of type 1 diabetes to study parallel alterations of nerves and microvessels following tissue ischemia. We designed an easily reproducible model of ischemic neuropathy induced by irreversible ligation of the femoral artery. We studied the evolution of behavioral function, epineurial and endoneurial vessel impairment, and large nerve myelinated fiber as well as small cutaneous unmyelinated fiber impairment for 1 month following the onset of ischemia. We observed a more severe hindlimb dysfunction and delayed recovery in diabetic animals. This was associated with reduced density of large arteries in the hindlimb and reduced sciatic nerve epineurial blood flow. A reduction in sciatic nerve endoneurial capillary density was also observed, associated with a reduction in small unmyelinated epidermal fiber number and large myelinated sciatic nerve fiber dysfunction. Moreover, vascular recovery was delayed, and nerve dysfunction was still present in diabetic animals at day 28. This easily reproducible model provides clear insight into the evolution over time of the impact of ischemia on nerve and microvessel homeostasis in the setting of diabetes. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

FTY720-loaded poly(DL-lactide-co-glycolide) electrospun scaffold significantly increases microvessel density over 7 days in streptozotocin-induced diabetic C57b16/J mice: preliminary results.

PubMed

Bowers, D T; Chhabra, P; Langman, L; Botchwey, E A; Brayman, K L

2011-11-01

Nanofiber scaffolds could improve islet transplant success by physically mimicking the shape of extracellular matrix and by acting as a drug-delivery vehicle. Scaffolds implanted in alternate transplant sites must be prevascularized or very quickly vascularized following transplantation to prevent hypoxia-induced islet necrosis. The local release of the S1P prodrug FTY720 induces diameter enlargement and increases in length density. The objective of this preliminary study was to evaluate length and diameter differences between diabetic and nondiabetic animals implanted with FTY720-containing electrospun scaffolds using intravital imaging of dorsal skinfold window chambers. Electrospun mats of randomly oriented fibers we created from polymer solutions of PLAGA (50:50 LA:GA) with and without FTY720 loaded at a ratio of 1:200 (FTY720:PLAGA by wt). The implanted fiber mats were 4 mm in diameter and ∼0.2 mm thick. Increases in length density and vessel diameter were assessed by automated analysis of images over 7 days in RAVE, a Matlab program. Image analysis of repeated measures of microvessel metrics demonstrated a significant increase in the length density from day 0 to day 7 in the moderately diabetic animals of this preliminary study (P < .05). Furthermore, significant differences in length density at day 0 and day 3 were found between recently STZ-induced moderately diabetic and nondiabetic animals in response to FTY720 local release (P < .05, Student t test). Driving the islet revascularization process using local release of factors, such as FTY720, from biodegradable polymers makes an attractive system for the improvement of islet transplant success. Preliminary study results suggest that a recently induced moderately diabetic state may potentiate the mechanism by which local release of FTY720 from polymer fibers increases length density of microvessels. Therefore, local release of S1P receptor-targeted drugs is under further investigation for improvement of transplanted islet function. Copyright © 2011. Published by Elsevier Inc.

Detection and quantification of mast cell, vascular endothelial growth factor, and microvessel density in human inflammatory periapical cysts and granulomas.

PubMed

Fonseca-Silva, T; Santos, C C O; Alves, L R; Dias, L C; Brito, M; De Paula, A M B; Guimarães, A L S

2012-09-01

To identify and quantify mast cell (MC), vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in human periapical cysts and granulomas. Archived samples of cysts (n = 40) and granulomas (n = 28) were sectioned and stained with toluidine blue. MCs were identified and counted. Immunohistochemical reactions were employed to evaluate the tissue expression of VEGF and vessels. MVD was estimated by determining the areas of tissue labelled with CD31 antibody. The data were analysed using the Mann-Whitney test (P < 0.05). MCs were observed in the peripheral regions of both lesion types, whilst VEGF and MVD were distributed in the stroma. The presence of MCs was higher in cysts than in granulomas (P < 0.05). VEGF and MVD expression were similar in these lesions. The highest number of MCs was observed in cysts. Moreover, the identification of VEGF and MVD was consistent with the immune mechanisms involved in the lesions. © 2012 International Endodontic Journal.

[Inhibitory effect of taspine on mouse S180 sarcoma and its mechanism].

PubMed

Zhang, Yan-Min; He, Lang-Chong; Wang, Hong-Ying

2007-05-01

To study the inhibition effect of taspine on mouse S180 sarcoma and its mechanism. The mouse S180 sarcoma model was established and used to observe the antitumor activity of taspine. The microvessel density and protein expressing of the VEGF, bFGF, Bcl-2 and Bax in the tumor were measured by immunohistochemistry. Taspine showed antitumor activity on the mouse S180 sarcoma in a good dose-dependent manner. The inhibition rates on tumor of taspine at low, middle and high concentrations were 39.08% , 43.99% and 48.60%, respectively. The microvessel density and protein expressing of the VEGF, bFGF, Bcl-2 and Bax in the tumor were decreased compared with the negative control. The ratio of Bax to Bcl-2 was increased. Taspine has antitumor effect on the S180 sarcoma, and the mechanism may be through the way of decreasing the expressing of the VEGF, bFGF, Bcl-2 and Bax and inducing the vascular endothelial cell apoptosis.

Anatomic distribution of nerves and microvascular density in the human anterior vaginal wall: prospective study.

PubMed

Li, Ting; Liao, Qinping; Zhang, Hong; Gao, Xuelian; Li, Xueying; Zhang, Miao

2014-01-01

The presence of the G-spot (an assumed erotic sensitive area in the anterior wall of the vagina) remains controversial. We explored the histomorphological basis of the G-spot. Biopsies were drawn from a 12 o'clock direction in the distal- and proximal-third areas of the anterior vagina of 32 Chinese subjects. The total number of protein gene product 9.5-immunoreactive nerves and smooth muscle actin-immunoreactive blood vessels in each specimen was quantified using the avidin-biotin-peroxidase assay. Vaginal innervation was observed in the lamina propria and muscle layer of the anterior vaginal wall. The distal-third of the anterior vaginal wall had significantly richer small-nerve-fiber innervation in the lamina propria than the proximal-third (p = 0.000) and in the vaginal muscle layer (p = 0.006). There were abundant microvessels in the lamina propria and muscle layer, but no small vessels in the lamina propria and few in the muscle layer. Significant differences were noted in the number of microvessels when comparing the distal- with proximal-third parts in the lamina propria (p = 0.046) and muscle layer (p = 0.002). Significantly increased density of nerves and microvessels in the distal-third of the anterior vaginal wall could be the histomorphological basis of the G-spot. Distal anterior vaginal repair could disrupt the normal anatomy, neurovascular supply and function of the G-spot, and cause sexual dysfunction.

Microvascular dysfunction with increased vascular leakage response in mice systemically exposed to arsenic.

PubMed

Chen, Shih-Chieh; Huang, Shin-Yin; Lu, Chi-Yu; Hsu, Ya-Hung; Wang, Dean-Chuan

2014-09-01

The mechanisms underlying cardiovascular disease induced by arsenic exposure are not completely understood. The objectives of this study were to investigate whether arsenic-fed mice have an increased vascular leakage response to vasoactive agents and whether enhanced type-2 protein phosphatase (PP2A) activity is involved in mustard oil-induced leakage. ICR mice were fed water or sodium arsenite (20 mg/kg) for 4 or 8 weeks. The leakage response to vasoactive agents was quantified using the Evans blue (EB) technique or vascular labeling with carbon particles. Increased EB leakage and high density of carbon-labeled microvessels were detected in arsenic-fed mice treated with mustard oil. Histamine induced significantly higher vascular leakage in arsenic-fed mice than in water-fed mice. Pretreatment with the PP2A inhibitor okadaic acid or the neurokinin 1 receptor (NK1R) blocker RP67580 significantly reduced mustard oil-induced vascular leakage in arsenic-fed mice. The protein levels of PP2Ac and NK1R were similar in both groups. PP2A activity was significantly higher in the arsenic-fed mice compared with the control group. These findings indicate that microvessels generally respond to vasoactive agents, and that the increased PP2A activity is involved in mustard oil-induced vascular leakage in arsenic-fed mice. Arsenic may initiate endothelial dysfunction, resulting in vascular leakage in response to vasoactive agents.

Angiogenesis extent and macrophage density increase simultaneously with pathological progression in B-cell non-Hodgkin's lymphomas

PubMed Central

Vacca, A; Ribatti, D; Ruco, L; Giacchetta, F; Nico, B; Quondamatteo, F; Ria, R; Iurlaro, M; Dammacco, F

1999-01-01

Node biopsies of 30 benign lymphadenopathies and 71 B-cell non-Hodgkin's lymphomas (B-NHLs) were investigated for microvessel and macrophage counts using immunohistochemistry and morphometric analysis. Both counts were significantly higher in B-NHL. Moreover, when these were grouped into low-grade and high-grade lymphomas, according to the Kiel classification and Working Formulation (WF), statistically significant higher counts were found in the high-grade tumours. Immunohistochemistry and electron microscopy revealed a close spatial association between microvessels and macrophages. Overall, the results suggest that, in analogy to what has already been shown in solid tumours, angiogenesis occurring in B-NHLs increases with tumour progression, and that macrophages promote the induction of angiogenesis via the release of their angiogenic factors. © 1999 Cancer Research Campaign PMID:10070898

Structural and functional bases of laser-microvessels interaction

NASA Astrophysics Data System (ADS)

Kozlov, Valentine I.; Terman, Oleg A.; Builin, Vitalij; Lebedeva, Natalia A.; Samoilov, Nickolai

1993-07-01

Structural and functional microcirculatory changes in tissues and organs (muscles, liver, derma, epinephros, brain cortex) under various dosages and powers of laser irradiation in the red (633 nm) and near infrared (890 nm) spectrum regions have been studied in experiments and clinic. In case of nonsensitized tissues the `photoactivation' range of power densities and doses of laser irradiation has been established. We have identified a short-term reaction of microvessels and a long-term reaction (adaptation). The former consists of intensification of microcirculation and metabolism rise in parenchymatous cells; the latter is connected with neoangiogenesis acceleration. The intensification of the blood microcirculation includes a dilation of microvessels of all orders, an amplification of arteriolar vasomotions and an opening of `reserved' capillaries. Data on the structural reconstruction of myocytes and endotheliocytes have shown that the high differential parenchymatous cells and its membrane structures are sensitive to low energy laser irradiation and, on the other hand, under low energy laser irradiation there is an activation of synthetic processes in the cells. Thus, during the laser-tissue interaction in such complex system as human organism the microcirculation plays the key role among the other systems.

Expression and localization of the vascular endothelial growth factor and changes of microvessel density during hair follicle development of Liaoning cashmere goats.

PubMed

Zhang, Q L; Li, J P; Li, Y M; Chang, Q; Chen, Y; Jiang, H Z; Zhao, Z H; Guo, D

2013-12-10

Vascular endothelial growth factors (VEGFs) play important roles in neovascularization, tissue development, and angiogenesis. In this study, changes in VEGF expression patterns and microvessel density (MVD), and their correlations, were investigated during hair follicle development in epidermal appendages of Liaoning cashmere goats. Polyclonal antibodies to VEGF and microvessels were used for monthly immunohistochemical examinations of normal skin specimens from adult female goats for one year. VEGF was expressed in the hair bulb of primary and secondary hair follicles, the outer and inner root sheaths, sebaceous glands (ductal and secretory portions), eccrine sweat glands (ductal and secretory portions), and the epidermis. Abundant expression of VEGF was observed in the follicular basement membrane zone surrounding the bulb matrix and in ductal and secretory portions of eccrine sweat glands. The change in VEGFs in primary hair follicles showed a bimodal pattern, with the first peak observed from March to May, and the second in August. Maximal expression in secondary hair follicles occurred in May and August. Therefore, VEGF expression in primary and secondary hair follicles is synchronized throughout the year, and is correlated to hair development. In the later telogen and anagen phases, VEGF expression was higher in the secondary, compared to the primary, hair follicle. Changes in MVD also showed a bimodal pattern with peaks in May and August. VEGF expression and MVD showed moderate and strongly positive correlation in the primary and secondary hair follicles, respectively. Therefore, MVD and VEGF are closely related to the processes involved in hair cycle regulation.

Growth inhibition of malignant melanoma by intermediate frequency alternating electric fields, and the underlying mechanisms.

PubMed

Chen, H; Liu, R; Liu, J; Tang, J

2012-01-01

This study investigated the antitumour effects of intermediate frequency alternating electric fields (IF-AEF) in a murine melanoma cell line (B16F10) and a mouse tumour model. IF-AEF was applied at 100 kHz. Proliferation of B16F10 cells in vitro was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. IF-AEF was applied in vivo to mice bearing B16F10 tumours. Terminal deoxy nucleotidyl transferase-mediated dUTP nick end labelling (TUNEL) assay for apoptosis, and immunohistochemical detection of CD34 and vascular endothelial growth factor (VEGF), were performed. IF-AEF inhibited the proliferation of B16F10 cells in an electrical intensity and time-dependent manner. Treatment with IF-AEF for 7 days significantly inhibited the growth of tumours compared with untreated controls. IF-AEF induced apoptosis in vivo and reduced CD34-positive cell numbers; CD34 is a special marker of microvessel density. IF-AEF reduced microvessel density related to tumour growth and may serve as a therapeutic strategy for cancer treatment.

Phase II Study of Neoadjuvant Bevacizumab and Radiotherapy for Resectable Soft Tissue Sarcomas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoon, Sam S., E-mail: syoon@partners.org; Department of Cancer Biology, University of Pennsylvania School of Medicine, Philadelphia, PA; Duda, Dan G.

Purpose: Numerous preclinical studies have demonstrated that angiogenesis inhibitors can increase the efficacy of radiotherapy (RT). We sought to examine the safety and efficacy of bevacizumab (BV) and RT in soft tissue sarcomas and explore biomarkers to help determine the treatment response. Methods and Materials: Patients with {>=}5 cm, intermediate- or high-grade soft tissue sarcomas at significant risk of local recurrence received neoadjuvant BV alone followed by BV plus RT before surgical resection. Correlative science studies included analysis of the serial blood and tumor samples and serial perfusion computed tomography scans. Results: The 20 patients had a median tumor sizemore » of 8.25 cm, with 13 extremity, 1 trunk, and 6 retroperitoneal/pelvis tumors. The neoadjuvant treatment was well tolerated, with only 4 patients having Grade 3 toxicities (hypertension, liver function test elevation). BV plus RT resulted in {>=}80% pathologic necrosis in 9 (45%) of 20 tumors, more than double the historical rate seen with RT alone. Three patients had a complete pathologic response. The median microvessel density decreased 53% after BV alone (p <.05). After combination therapy, the median tumor cell proliferation decreased by 73%, apoptosis increased 10.4-fold, and the blood flow, blood volume, and permeability surface area decreased by 62-72% (p <.05). Analysis of gene expression microarrays of untreated tumors identified a 24-gene signature for treatment response. The microvessel density and circulating progenitor cells at baseline and the reduction in microvessel density and plasma soluble c-KIT with BV therapy also correlated with a good pathologic response (p <.05). After a median follow-up of 20 months, only 1 patient had developed local recurrence. Conclusions: The results from the present exploratory study indicated that BV increases the efficacy of RT against soft tissue sarcomas and might reduce the incidence of local recurrence. Thus, this regimen warrants additional investigation. Gene expression profiles and other tissue and circulating biomarkers showed promising correlations with treatment response.« less

Dapsone protects brain microvascular integrity from high-fat diet induced LDL oxidation.

PubMed

Zhan, Rui; Zhao, Mingming; Zhou, Ting; Chen, Yue; Yu, Weiwei; Zhao, Lei; Zhang, Tao; Wang, Hecheng; Yang, Huan; Jin, Yinglan; He, Qihua; Yang, Xiaoda; Guo, Xiangyang; Willard, Belinda; Pan, Bing; Huang, Yining; Chen, Yingyu; Chui, Dehua; Zheng, Lemin

2018-06-07

Atherosclerosis was considered to induce many vascular-related complications, such as acute myocardial infarction and stroke. Abnormal lipid metabolism and its peroxidation inducing blood-brain barrier (BBB) leakage were associated with the pre-clinical stage of stroke. Dapsone (DDS), an anti-inflammation and anti-oxidation drug, has been found to have protective effects on vascular. However, whether DDS has a protective role on brain microvessels during lipid oxidation had yet to be elucidated. We investigated brain microvascular integrity in a high-fat diet (HFD) mouse model. We designed this study to explore whether DDS had protective effects on brain microvessels under lipid oxidation and tried to explain the underlying mechanism. In our live optical study, we found that DDS significantly attenuated brain microvascular leakage through reducing serum oxidized low-density lipoprotein (oxLDL) in HFD mice (p < 0.001), and DDS significantly inhibited LDL oxidation in vitro (p < 0.001). Our study showed that DDS protected tight junction proteins: ZO-1 (p < 0.001), occludin (p < 0.01), claudin-5 (p < 0.05) of microvascular endothelial cells in vivo and in vitro. DDS reversed LAMP1 aggregation in cytoplasm, and decreased the destruction of tight junction protein: ZO-1 in vitro. We first revealed that DDS had a protective role on cerebral microvessels through preventing tight junction ZO-1 from abnormal degradation by autophagy and reducing lysosome accumulation. Our findings suggested the significance of DDS in protecting brain microvessels under lipid metabolic disorders, which revealed a novel potential therapeutic strategy in brain microvascular-related diseases.

Interleukin 35 Expression Correlates With Microvessel Density in Pancreatic Ductal Adenocarcinoma, Recruits Monocytes, and Promotes Growth and Angiogenesis of Xenograft Tumors in Mice.

PubMed

Huang, Chongbiao; Li, Zengxun; Li, Na; Li, Yang; Chang, Antao; Zhao, Tiansuo; Wang, Xiuchao; Wang, Hongwei; Gao, Song; Yang, Shengyu; Hao, Jihui; Ren, He

2018-02-01

Cells of the monocyte lineage contribute to tumor angiogenesis. Interleukin 35 (IL35) is a member of the IL12 family produced by regulatory, but not effector, T cells. IL35 is a dimer comprising the IL12 alpha and IL27 beta chains, encoded by IL12A and EBI3, respectively. Expression of IL35 is increased in pancreatic ductal adenocarcinomas (PDACs) compared with normal pancreatic tissues, and promotes metastasis. We investigated the role of IL35 in monocyte-induced angiogenesis of PDAC in mice. We measured levels of IL35 protein, microvessel density, and numbers of monocytes in 123 sequential PDAC tissues from patients who underwent surgery in China in 2010. We performed studies with the human PDAC cell lines CFPAC-1, BxPC-3, Panc-1, MIA-PaCa-2, and mouse PDAC cell line Pan02. Monocyte subsets were isolated by flow cytometry from human peripheral blood mononuclear cells. Fused human or mouse IL12A and EBI3 genes were overexpressed in PDAC cells or knocked down using small hairpin RNAs. Cells were grown as xenograft tumors in SCID mice; some mice were given injections of an IL35-neutralizing antibody and tumor growth was monitored. We performed chemotaxis assays to measure the ability of IL35 to recruit monocytes. We analyzed mRNA sequences of 179 PDACs in the Cancer Genome Atlas to identify correlations between expression of IL12A and EBI3 and monocyte markers. Monocytes incubated with IL35 or PDAC cell supernatants were analyzed in tube formation and endothelial migration assays. In PDAC samples from patients, levels of IL35 mRNA and protein correlated with microvessel density and infiltration of monocyte lineage cells. In cells and mice with xenograft tumors, IL35 increased recruitment of monocytes into PDAC tumors, which required CCL5. Upon exposure to IL35, monocytes increased expression of genes whose products promote angiogenesis (CXCL1 and CXCL8). IL35 activated transcription of CCL5, CXCL1, and CXCL8 by inducing GP130 signaling, via IL12RB2 and phosphorylation of STAT1 and STAT4. A combination of a neutralizing antibody against IL35 and gemcitabine significantly decreased monocyte infiltration, microvessel density, and volume of xenograft tumors grown from PDAC cells in mice. PDAC cells produce IL35 to recruit monocytes via CCL5 and induce macrophage to promote angiogenesis via expression of CXCL1 and CXCL8. IL35 signaling promotes angiogenesis and growth of xenograft tumors from PDAC cells in mice. IL35 might serve as a therapeutic target for patients with pancreatic cancer. Copyright © 2018. Published by Elsevier Inc.

Clinical study of contrast-enhanced digital mammography and the evaluation of blood and lymphatic microvessel density

PubMed Central

Cruz-Bastida, Juan P; Rosado-Méndez, Iván M; Villaseñor-Navarro, Yolanda; Pérez-Ponce, Héctor; Galván, Héctor A; Trujillo-Zamudio, Flavio E; Sánchez-Suárez, Patricia; Benítez-Bribiesca, Luis

2016-01-01

Objective: To correlate image parameters in contrast-enhanced digital mammography (CEDM) with blood and lymphatic microvessel density (MVD). Methods: 18 Breast Imaging-Reporting and Data System (BI-RADS)-4 to BI-RADS-5 patients were subjected to CEDM. Craniocaudal views were acquired, two views (low and high energy) before iodine contrast medium (CM) injection and four views (high energy) 1–5 min afterwards. Processing included registration and two subtraction modalities, traditional single-energy temporal (high-energy) and “dual-energy temporal with a matrix”, proposed to improve lesion conspicuity. Images were calibrated into iodine thickness, and iodine uptake, contrast, time–intensity and time–contrast kinetic curves were quantified. Image indicators were compared with MVD evaluated by anti-CD105 and anti-podoplanin (D2-40) immunohistochemistry. Results: 11 lesions were cancerous and 7 were benign. CEDM subtraction strongly increased conspicuity of lesions enhanced by iodine uptake. A strong correlation was observed between lymphatic vessels and blood vessels; all benign lesions had <30 blood microvessels per field, and all cancers had more than this value. MVD showed no correlation with iodine uptake, nor with contrast. The most frequent curve was early uptake followed by plateau for uptake and contrast in benign and malignant lesions. The positive-predictive value of uptake dynamics was 73% and that of contrast was 64%. Conclusion: CEDM increased lesion visibility and showed additional features compared with conventional mammography. Lack of correlation between image parameters and MVD is probably due to tumour tissue heterogeneity, mammography projective nature and/or dependence of extracellular iodine irrigation on tissue composition. Advances in knowledge: Quantitative analysis of CEDM images was performed. Image parameters and MVD showed no correlation. Probably, this is indication of the complex dependence of CM perfusion on tumour microenvironment. PMID:27376457

Erythropoietin promotes network formation of transplanted adipose tissue-derived microvascular fragments.

PubMed

Karschnia, P; Scheuer, C; Heß, A; Später, T; Menger, M D; Laschke, M W

2018-05-09

The seeding of tissue constructs with adipose tissue-derived microvascular fragments (ad-MVF) is an emerging pre-vascularisation strategy. Ad-MVF rapidly reassemble into new microvascular networks after in vivo implantation. Herein it was analysed whether this process was improved by erythropoietin (EPO). Ad-MVF were isolated from green fluorescent protein (GFP)+ as well as wild-type C57BL/6 mice and cultivated for 24 h in medium supplemented with EPO (20 IU/mL) or vehicle. Freshly isolated, non-cultivated ad-MVF served as controls. Protein expression, cell viability and proliferation of ad-MVF were assessed by proteome profiler array and fluorescence microscopy. GFP+ ad-MVF were seeded on collagen-glycosaminoglycan matrices, which were implanted into dorsal skinfold chambers of C57BL/6 mice, to analyse their vascularisation over 14 d by intravital fluorescence microscopy, histology and immunohistochemistry. Cultivation up-regulated the expression of pro- and anti-angiogenic factors within both vehicle- and EPO-treated ad-MVF when compared with non-cultivated controls. Moreover, EPO treatment suppressed cultivation-associated apoptosis and significantly increased the number of proliferating endothelial cells in ad-MVF when compared with vehicle-treated and non-cultivated ad-MVF. Accordingly, implanted matrices seeded with EPO-treated ad-MVF exhibited an improved vascularisation, as indicated by a significantly higher functional microvessel density. The matrices of the three groups contained a comparably large fraction of GFP+ microvessels originating from the ad-MVF, whereas the tissue surrounding the matrices seeded with EPO-treated ad-MVF exhibited a significantly increased microvessel density when compared with the other two groups. These findings indicated that EPO represents a promising cytokine to further boost the excellent vascularisation properties of ad-MVF in tissue-engineering applications.

Arachidonic acid and prostaglandin endoperoxide metabolism in isolated rabbit and coronary microvessels and isolated and cultivated coronary microvessel endothelial cells.

PubMed Central

Gerritsen, M E; Cheli, C D

1983-01-01

Isolated microvessels and isolated and cultured microvessel endothelial cells were prepared from rabbit cardiac muscle. Pathways of arachidonic acid metabolism were determined by measurement of exogenous substrate utilization [( 1-14C]arachidonic acid incorporation and release from intact tissue and cells; [1-14C]prostaglandin H2 (PGH2) metabolism by broken cell preparations) and by quantification of endogenous products (immunoreactive 6-keto-prostaglandin F1 alpha (PGF1 alpha) and prostaglandin E (PGE) release) by selective radioimmunoassay. Rabbit coronary microvessels and derived microvascular endothelial cells (RCME cells) synthesized two major products of the cyclooxygenase pathway: 6-keto-PGF1 alpha (hydrolytic product of prostaglandin I2) and PGE2. A reduced glutathione requiring PGH-E isomerase was demonstrated in coronary microvessels and RCME cells, but not in rabbit circumflex coronary artery or aorta. In addition, a minor amount of a compound exhibiting similar characteristics to 6-keto-PGE1 was found to be produced by microvessels and RCME cells. Measurement of endogenously released prostaglandins indicated that under basal and stimulated conditions, PGE release exceeded that of 6-keto-PGF1 alpha. Microvessels and microvessel endothelial cells derived from cardiac muscle of rabbit exhibit pathways of arachidonate metabolism that are different from those of many large blood vessels and derived endothelial cells. Images PMID:6415116

SH3-domain binding protein 1 in the tumor microenvironment promotes hepatocellular carcinoma metastasis through WAVE2 pathway

PubMed Central

Tao, Yiming; Hu, Kuan; Tan, Fengbo; Zhang, Sai; Zhou, Ming; Luo, Jia; Wang, Zhiming

2016-01-01

SH3-domain binding protein-1 (SH3BP1) specifically inactivating Rac1 and its target WAVE2 is required for cell motility. The present study shows SH3BP1 expression patterns in human HCC tissues and cell lines were examined. The regulation of SH3BP1 on HCC cell migration and invasion related to Rac1-WAVE2 signaling was characterized using in vitro and in vivo models. SH3BP1 overexpressed in HCC tissues and highly metastatic HCC cells was significantly associated vascular invasion (VI). SH3BP1 promoted VEGF secretion via Rac1-WAVE2 signaling, so as to exert an augmentation on cell invasion and microvessel formation. In three study cohorts with a total of 516 HCC patients, high SH3BP1 expression combined with high microvessel density (MVD) was confirmed as a powerful independent predictor of HCC prognosis in both training cohorts and validation cohort. Being an important angiogenic factor of HCC through Rac1-WAVE2 signaling, SH3BP1 promotes tumor invasion and microvessel formation contributing to HCC metastasis and recurrence. SH3BP1 is a novel WAVE2 regulator, a prognostic marker and a potential therapeutic target of HCC. PMID:26933917

SH3-domain binding protein 1 in the tumor microenvironment promotes hepatocellular carcinoma metastasis through WAVE2 pathway.

PubMed

Tao, Yiming; Hu, Kuan; Tan, Fengbo; Zhang, Sai; Zhou, Ming; Luo, Jia; Wang, Zhiming

2016-04-05

SH3-domain binding protein-1 (SH3BP1) specifically inactivating Rac1 and its target WAVE2 is required for cell motility. The present study shows SH3BP1 expression patterns in human HCC tissues and cell lines were examined. The regulation of SH3BP1 on HCC cell migration and invasion related to Rac1-WAVE2 signaling was characterized using in vitro and in vivo models. SH3BP1 overexpressed in HCC tissues and highly metastatic HCC cells was significantly associated vascular invasion (VI). SH3BP1 promoted VEGF secretion via Rac1-WAVE2 signaling, so as to exert an augmentation on cell invasion and microvessel formation. In three study cohorts with a total of 516 HCC patients, high SH3BP1 expression combined with high microvessel density (MVD) was confirmed as a powerful independent predictor of HCC prognosis in both training cohorts and validation cohort. Being an important angiogenic factor of HCC through Rac1-WAVE2 signaling, SH3BP1 promotes tumor invasion and microvessel formation contributing to HCC metastasis and recurrence. SH3BP1 is a novel WAVE2 regulator, a prognostic marker and a potential therapeutic target of HCC.

Relations of Digital Vascular Function, Cardiovascular Risk Factors, and Arterial Stiffness: The Brazilian Longitudinal Study of Adult Health (ELSA‐Brasil) Cohort Study

PubMed Central

Brant, Luisa C. C.; Hamburg, Naomi M.; Barreto, Sandhi M.; Benjamin, Emelia J.; Ribeiro, Antonio L. P.

2014-01-01

Background Vascular dysfunction is an early expression of atherosclerosis and predicts cardiovascular (CV) events. Peripheral arterial tonometry (PAT) evaluates basal pulse amplitude (BPA), endothelial function (PAT ratio), and wave reflection (PAT‐AIx) in the digital microvessels. In Brazilian adults, we investigated the correlations of PAT responses to CV risk factors and to carotid‐femoral pulse wave velocity (PWV), a measure of arterial stiffness. Methods and Results In a cross‐sectional study, 1535 participants of the ELSA‐Brasil cohort underwent PAT testing (52±9 years; 44% women). In multivariable analyses, more‐impaired BPA and PAT ratios were associated with male sex, higher body mass index (BMI), and total cholesterol/high‐density lipoprotein. Higher age and triglycerides were related to higher BPA, whereas lower systolic blood pressure, hypertension (HTN) treatment, and prevalent CV disease (CVD) were associated with lower PAT ratio. PAT‐AIx correlated positively with female sex, advancing age, systolic and diastolic blood pressures, and smoking and inversely to heart rate, height, BMI, and prevalent CVD. Black race was associated with lower BPA, higher PAT ratio, and PAT‐AIx. Microvessel vasodilator function was not associated with PWV. Higher PAT‐AIx was modestly correlated to higher PWV and PAT ratio and inversely correlated to BPA. Conclusion Metabolic risk factors are related to impaired microvessel vasodilator function in Brazil. However, in contrast to studies from the United States, black race was not associated with an impaired microvessel vasodilator response, implying that vascular function may vary by race across populations. PAT‐AIx relates to HTN, may be a valid measure of wave reflection, and provides distinct information from arterial stiffness. PMID:25510401

Prenatal alcohol exposure affects vasculature development in the neonatal brain.

PubMed

Jégou, Sylvie; El Ghazi, Faiza; de Lendeu, Pamela Kwetieu; Marret, Stéphane; Laudenbach, Vincent; Uguen, Arnaud; Marcorelles, Pascale; Roy, Vincent; Laquerrière, Annie; Gonzalez, Bruno José

2012-12-01

In humans, antenatal alcohol exposure elicits various developmental disorders, in particular in the brain. Numerous studies focus on the deleterious effects of alcohol on neural cells. Although recent studies suggest that alcohol can affect angiogenesis in adults, the impact of prenatal alcohol exposure on brain microvasculature remains poorly understood. We used a mouse model to investigate effects of prenatal alcohol exposure on the cortical microvascular network in vivo and ex vivo and the action of alcohol, glutamate, and vascular endothelial growth factor A (VEGF) on activity, plasticity, and survival of microvessels. We used quantitative reverse transcriptase polymerase chain reaction, Western blot, immunohistochemistry, calcimetry, and videomicroscopy. We characterized the effect of prenatal alcohol exposure on the cortical microvascular network in human controls and fetal alcohol syndrome (FAS)/partial FAS (pFAS) patients at different developmental stages. In mice, prenatal alcohol exposure induced a reduction of cortical vascular density, loss of the radial orientation of microvessels, and altered expression of VEGF receptors. Time-lapse experiments performed on brain slices revealed that ethanol inhibited glutamate-induced calcium mobilization in endothelial cells, affected plasticity, and promoted death of microvessels. These effects were prevented by VEGF. In humans, we evidenced a stage-dependent alteration of the vascular network in the cortices of fetuses with pFAS/FAS. Whereas no modification was observed from gestational week 20 (WG20) to WG22, the radial organization of cortical microvessels was clearly altered in pFAS/FAS patients from WG30 to WG38. Prenatal alcohol exposure affects cortical angiogenesis both in mice and in pFAS/FAS patients, suggesting that vascular defects contribute to alcohol-induced brain abnormalities. Copyright © 2012 American Neurological Association.

EASApprox® skin-stretching system: A secure and effective method to achieve wound closure.

PubMed

Song, Mingzhi; Zhang, Zhen; Liu, Tao; Liu, Song; Li, Gang; Liu, Zhaochang; Huang, Jingyang; Chen, Song; Li, Linan; Guo, Li; Qiu, Yang; Wan, Jiajia; Liu, Yuejian; Wu, Tao; Wang, Xiaoyong; Lu, Ming; Wang, Shouyu

2017-07-01

Large skin defects are commonly observed in the clinic and have attracted much attention recently. Therefore, finding an effective solution for large skin defects is a global problem. The objective of the present study was to assess the effectiveness of the EASApprox ® skin-stretching system for closing large skin defects. Skin defects (5×5 cm) were created on the forearms of 9 Bama miniature pigs, which were randomly divided into the following three groups: Direct suture, the new EASApprox ® skin-stretching device and Kirschner wires. Microcirculation was assessed before surgery and after wound closure. Following the different treatments, the defects were sutured, and wound healing was assessed based on a clinical score. Furthermore, microscopic and ultramicroscopic structures were evaluated, including collagen, elastic fibers and the microvessel density. Significant differences in the clinical score and microvessel density were observed among the groups. Additionally, the mean length obtained for elastic fibers was larger than that obtained for the other two groups. Finally, the new EASApprox ® skin-stretching device resulted in successful wound management and with only minor side effects on skin histology and microcirculation. Therefore, this method has the potential to be used for healing large skin defects.

Histopathological vascular investigation of the peritumoral brain zone of glioblastomas.

PubMed

Tamura, Ryota; Ohara, Kentaro; Sasaki, Hikaru; Morimoto, Yukina; Yoshida, Kazunari; Toda, Masahiro

2018-01-01

To date, no histopathological vascular investigation focusing on peritumoral brain zone (PBZ) has been reported for glioblastoma. We analyzed 10 newly diagnosed cases of glioblastomas. For these PBZs, histopathological investigation was performed by hematoxylin-eosin (H&E) staining and immunohistochemistry was analyzed for CD31, CD34, Factor VIII, VEGF, VEGFR-1/2, Ki67, p53 and nestin. Although it was difficult to identify PBZ by H&E, Ki67 and p53 staining, there were apparent differences in nestin staining among PBZ, tumor core (TC), and normal zone (NZ). Therefore, in this study, we divided PBZ from TC and NZ by nestin staining. Differences in histological features, microvessel density, expression of VEGF and its receptors were assessed for PBZ, TC and NZ. The microvessel density, as determined by counting CD31, CD34 and VEGF receptors, and VEGF-A expression were lower in PBZ than TC. The expression patterns for CD31, CD34 and VEGF receptors in vessels show dissociation in PBZ. In addition, the vascular characteristics of the PBZ may correlate with findings of radiographic imaging. We provide the first clinicopathological evidence that PBZ exhibits unique angiogenic characteristics. These in situ observations will help to elucidate the mechanisms of tumor recurrence.

IFATS Collection: Adipose-Derived Stromal Cells Improve the Foreign Body Response

PubMed Central

Prichard, Heather L.; Reichert, William; Klitzman, Bruce

2015-01-01

Many implanted devices fail due to the formation of an avascular capsule surrounding the device. Additionally, fat has long been known to promote healing and vascularization. The goals of this study were to identify potential mechanisms of the provascular actions of adipose-derived stromal cells (ASCs) and to improve implant biocompatibility. First, adult ASCs and fibroblasts from rats were attached to polyurethane and polystyrene in vitro and their cytokine secretion profile was analyzed. Secretion of vascular endothelial growth factor (VEGF) from ASCs was 10 –70 times higher than fibroblasts after 3 and 6 days. Next, polyurethane, bare and with cellular coatings, was implanted subcutaneously in rats. The fibrous capsule surrounding bare polyurethane implants was 17%–32% thicker and the amount of collagen was 27% greater than the capsule surrounding ASC-coated implants. Finally, the microvessel density adjacent to ASC-coated polyurethane was approximately 50%–80% higher than bare polyurethane. In summary, ASCs attached to polyurethane have a dramatically increased VEGF production compared with fibroblasts in vitro, and these cells also produce an increased microvessel density in the surrounding tissue when implanted subcutaneously in rats. PMID:18436858

Low-frequency ultrasound-mediated microvessel disruption combined with docetaxel to treat prostate carcinoma xenografts in nude mice: A novel type of chemoembolization

PubMed Central

Yang, Yu; Bai, Wenkun; Chen, Yini; Nan, Shuliang; Lin, Yanduan; Ying, Tao; Hu, Bing

2016-01-01

The aim of the present study was to investigate whether low-frequency ultrasound (US)-mediated microvessel disruption combined with docetaxel (DTX) can be used as a novel type of chemoembolization. Mice were assigned to four groups: i) The USMB group, treated with low-frequency US combined with microbubbles (USMB); ii) the DTX group, treated with DTX; iii) the USMB + DTX group, treated with combined therapy; and iv) the control group, which was untreated. Immediately after the first treatment, the average peak intensity (API) on contrast-enhanced US was calculated, and tumors were excised for hematoxylin and eosin (HE) staining. At 2 weeks post-treatment, the tumor volumes and wet weights were calculated, and tumors were excised for immunohistochemistry to calculate apoptotic index (AI), proliferative index (PI) and microvessel density (MVD) values. Immediately after the first treatment, in the DTX and control groups, the tumors demonstrated abundant perfusion enhancement, while in the USMB + DTX and USMB groups, blood perfusion of the tumors was interrupted. Compared with that of the control group, the API was significantly lower in the USMB + DTX USMB groups (all P<0.001). HE staining showed that tumor microvasculature was disrupted into flaky hematomas and severely dilated microvessels in the USMB + DTX and USMB groups. In the DTX and control groups, there was no distinct evidence of the disruption and dilation of blood microvessels. At the end of the treatment, the mean tumor inhibition ratio was 73.33, 46.67 and 33.33% for the USMB + DTX, DTX and USMB groups, respectively. The USMB + DTX group had the highest AI, and the lowest PI and MVD compared with the other groups, although the difference between the USMB + DTX and DTX groups with regard to PI and MVD was not significant (USMB + DTX vs. DTX group, P=0.345 and P=0.059, respectively). In conclusion, as a novel type of chemoembolization, USMB combined with DTX is more effective than USMB or DTX alone in inhibiting tumor growth via the enhancement of apoptosis, and the suppression of proliferation and angiogenesis. PMID:27446386

Noise Equalization for Ultrafast Plane Wave Microvessel Imaging.

PubMed

Song, Pengfei; Manduca, Armando; Trzasko, Joshua D; Chen, Shigao

2017-11-01

Ultrafast plane wave microvessel imaging significantly improves ultrasound Doppler sensitivity by increasing the number of Doppler ensembles that can be collected within a short period of time. The rich spatiotemporal plane wave data also enable more robust clutter filtering based on singular value decomposition. However, due to the lack of transmit focusing, plane wave microvessel imaging is very susceptible to noise. This paper was designed to: 1) study the relationship between ultrasound system noise (primarily time gain compensation induced) and microvessel blood flow signal and 2) propose an adaptive and computationally cost-effective noise equalization method that is independent of hardware or software imaging settings to improve microvessel image quality.

Astrocytic Adrenoceptors: A Major Drug Target in Neurological and Psychiatric Disorders

DTIC Science & Technology

2004-01-01

phosphorylation was found mainly in microvessels and astrocytes.. B. Dysfunction 1. Multiple Sclerosis, Canine Distemper and EAE In order to initiate the...astrocytes is seen in canine distemper encephalitis, a demyelinating disease in dogs that closely resembles multiple sclerosis and is caused by a virus

Letters: Noise Equalization for Ultrafast Plane Wave Microvessel Imaging

PubMed Central

Song, Pengfei; Manduca, Armando; Trzasko, Joshua D.

2017-01-01

Ultrafast plane wave microvessel imaging significantly improves ultrasound Doppler sensitivity by increasing the number of Doppler ensembles that can be collected within a short period of time. The rich spatiotemporal plane wave data also enables more robust clutter filtering based on singular value decomposition (SVD). However, due to the lack of transmit focusing, plane wave microvessel imaging is very susceptible to noise. This study was designed to: 1) study the relationship between ultrasound system noise (primarily time gain compensation-induced) and microvessel blood flow signal; 2) propose an adaptive and computationally cost-effective noise equalization method that is independent of hardware or software imaging settings to improve microvessel image quality. PMID:28880169

Peroxynitrite mediates testosterone-induced vasodilation of microvascular resistance vessels.

PubMed

Puttabyatappa, Yashoda; Stallone, John N; Ergul, Adviye; El-Remessy, Azza B; Kumar, Sanjiv; Black, Stephen; Johnson, Maribeth; Owen, Mary P; White, Richard E

2013-04-01

Our knowledge of how androgens influence the cardiovascular system is far from complete, and this lack of understanding is especially true of how androgens affect resistance vessels. Our aim was to identify the signaling mechanisms stimulated by testosterone (TES) in microvascular arteries and to understand how these mechanisms mediate TES-induced vasodilation. Mesenteric microvessels were isolated from male Sprague-Dawley rats. Tension studies demonstrated a rapid, concentration-dependent, vasodilatory response to TES that did not involve protein synthesis or aromatization to 17β-estradiol. Dichlorofluorescein fluorescence and nitrotyrosine immunoblot experiments indicated that TES stimulated peroxynitrite formation in microvessels, and functional studies demonstrated that TES-induced vasodilation was inhibited by scavenging peroxynitrite. As predicted, TES enhanced the production of both peroxynitrite precursors (i.e., superoxide and nitic oxide), and xanthine oxidase was identified as the likely source of TES-stimulated superoxide production. Functional and biochemical studies indicated that TES signaling involved activity of the phosphoinositide 3 (PI3) kinase-protein kinase B (Akt) cascade initiated by activation of the androgen receptor and culminated in enhanced production of cGMP and microvascular vasodilation. These findings, derived from a variety of analytical and functional approaches, provide evidence for a novel nongenomic signaling mechanism for androgen action in the microvasculature: TES-stimulated vasodilation mediated primarily by peroxynitrite formed from xanthine oxidase-generated superoxide and NO. This response was associated with activation of the PI3 kinase-Akt signaling cascade initiated by activation of the androgen receptor. We propose this mechanism could account for TES-stimulated cGMP production in microvessels and, ultimately, vasodilation.

Peroxynitrite Mediates Testosterone-Induced Vasodilation of Microvascular Resistance Vessels

PubMed Central

Puttabyatappa, Yashoda; Stallone, John N.; Ergul, Adviye; El-Remessy, Azza B.; Kumar, Sanjiv; Black, Stephen; Johnson, Maribeth; Owen, Mary P.

2013-01-01

Our knowledge of how androgens influence the cardiovascular system is far from complete, and this lack of understanding is especially true of how androgens affect resistance vessels. Our aim was to identify the signaling mechanisms stimulated by testosterone (TES) in microvascular arteries and to understand how these mechanisms mediate TES-induced vasodilation. Mesenteric microvessels were isolated from male Sprague-Dawley rats. Tension studies demonstrated a rapid, concentration-dependent, vasodilatory response to TES that did not involve protein synthesis or aromatization to 17β-estradiol. Dichlorofluorescein fluorescence and nitrotyrosine immunoblot experiments indicated that TES stimulated peroxynitrite formation in microvessels, and functional studies demonstrated that TES-induced vasodilation was inhibited by scavenging peroxynitrite. As predicted, TES enhanced the production of both peroxynitrite precursors (i.e., superoxide and nitic oxide), and xanthine oxidase was identified as the likely source of TES-stimulated superoxide production. Functional and biochemical studies indicated that TES signaling involved activity of the phosphoinositide 3 (PI3) kinase-protein kinase B (Akt) cascade initiated by activation of the androgen receptor and culminated in enhanced production of cGMP and microvascular vasodilation. These findings, derived from a variety of analytical and functional approaches, provide evidence for a novel nongenomic signaling mechanism for androgen action in the microvasculature: TES-stimulated vasodilation mediated primarily by peroxynitrite formed from xanthine oxidase-generated superoxide and NO. This response was associated with activation of the PI3 kinase-Akt signaling cascade initiated by activation of the androgen receptor. We propose this mechanism could account for TES-stimulated cGMP production in microvessels and, ultimately, vasodilation. PMID:23318471

Downregulation of MicroRNA-126 Contributes to the Failing Right Ventricle in Pulmonary Arterial Hypertension.

PubMed

Potus, François; Ruffenach, Grégoire; Dahou, Abdellaziz; Thebault, Christophe; Breuils-Bonnet, Sandra; Tremblay, Ève; Nadeau, Valérie; Paradis, Renée; Graydon, Colin; Wong, Ryan; Johnson, Ian; Paulin, Roxane; Lajoie, Annie C; Perron, Jean; Charbonneau, Eric; Joubert, Philippe; Pibarot, Philippe; Michelakis, Evangelos D; Provencher, Steeve; Bonnet, Sébastien

2015-09-08

Right ventricular (RV) failure is the most important factor of both morbidity and mortality in pulmonary arterial hypertension (PAH). However, the underlying mechanisms resulting in the failed RV in PAH remain unknown. There is growing evidence that angiogenesis and microRNAs are involved in PAH-associated RV failure. We hypothesized that microRNA-126 (miR-126) downregulation decreases microvessel density and promotes the transition from a compensated to a decompensated RV in PAH. We studied RV free wall tissues from humans with normal RV (n=17), those with compensated RV hypertrophy (n=8), and patients with PAH with decompensated RV failure (n=14). Compared with RV tissues from patients with compensated RV hypertrophy, patients with decompensated RV failure had decreased miR-126 expression (quantitative reverse transcription-polymerase chain reaction; P<0.01) and capillary density (CD31(+) immunofluorescence; P<0.001), whereas left ventricular tissues were not affected. miR-126 downregulation was associated with increased Sprouty-related EVH1 domain-containing protein 1 (SPRED-1), leading to decreased activation of RAF (phosphorylated RAF/RAF) and mitogen-activated protein kinase (MAPK); (phosphorylated MAPK/MAPK), thus inhibiting the vascular endothelial growth factor pathway. In vitro, Matrigel assay showed that miR-126 upregulation increased angiogenesis of primary cultured endothelial cells from patients with decompensated RV failure. Furthermore, in vivo miR-126 upregulation (mimic intravenous injection) improved cardiac vascular density and function of monocrotaline-induced PAH animals. RV failure in PAH is associated with a specific molecular signature within the RV, contributing to a decrease in RV vascular density and promoting the progression to RV failure. More importantly, miR-126 upregulation in the RV improves microvessel density and RV function in experimental PAH. © 2015 American Heart Association, Inc.

Lymphangiogenesis and angiogenesis in oral cavity and lower lip squamous cell carcinoma.

PubMed

Alaeddini, Mojgan; Etemad-Moghadam, Shahroo

2016-01-01

Tumors of the lip and oral cavity differ in various aspects; therefore a clarification of the distinctions among these sites may help to better understand the biologic behavior of neoplasms occurring in these locations. Considering that angiogenesis and lymphangiogenesis are two major elements that can influence various aspects of tumor biology, we aimed to compare these factors between squamous cell carcinoma of the lower lip and oral cavity. A total of 84 primary squamous cell carcinomas including 45 oral and 39 lower lip tumors were selected and immunohistochemically stained with monoclonal antibody against D2-40 and CD105. Mean microvessel density was assessed in tumoral tissue, while lymphatic vessel density was calculated in both neoplastic tissue and invasion front. Data were statistically analyzed using t-test and p-values of <0.05 were considered significant. We found a mean microvessel density±standard deviation of 31.94±18.9 in oral cavity and 27.54±20.8 in lower lip squamous cell carcinomas, with no significant difference (p=0.32). Mean lymphatic vessel density±standard deviation was 13.05±8.2 and 16.57±10.79 in of oral cavity and lower lip neoplastic tissue, respectively. The corresponding values were 9.94±5.59 and 12.50±7.8 in the invasive front. Significant differences were not observed in either of the lymphatic vessel density variables between the two sites. According to our results, it seems that the search for additional factors other than those related to the vasculature should continue, to help clarify the differences in biologic behavior between lower lip and oral cavity squamous cell carcinomas. Copyright © 2015 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Histomorphometric Analysis of Angiogenesis using CD31 Immunomarker and Mast Cell Density in Oral Premalignant and Malignant Lesions: A Pilot Study.

PubMed

Jyothsna, M; Rammanohar, M; Kumar, Kiran

2017-01-01

Mast cells have been implicated in promoting angiogenesis in malignant tumors of lung, oesophagus and breast, but there are few studies on Oral Squamous Cell Carcinomas (OSCC). Most oral squamous cell carcinomas arise from pre-existing precancerous lesions exhibiting epithelial dysplasia. The present pilot study attempts to compare Mast Cell Density (MCD), Microvessel Density (MVD), Microvessel Area (MVA) histomorphometrically between normal buccal mucosa, severe epithelial dysplasia and OSCC and to correlate the role of mast cells and angiogenesis in tumor progression. The retrospective study was conducted on eight cases of OSCC, eight cases of severe epithelial dysplasia and five cases of normal buccal mucosa. Immunohistochemical staining with anti CD-31, to demonstrate angiogenesis and toluidine blue staining for mast cells were employed. MVA, MVD and MCD were calculated using the measurement tools of the image analysis software and compared between the groups. One way ANOVA (Analysis of Variance) was used for comparing the parameter for multiple groups followed by Games Howell test. To assess the relationship between micro vessel density and mast cell density, Karl Pearson's correlation was used. MCD and MVD increased with disease progression and were statistically higher in OSCC than in severe epithelial dysplasia and normal buccal mucosa (p<0.001). MVA increased from normal to severe dysplasia and decreased from dysplasia to OSCC, may be due to revascularization of tumor tissue. A positive correlation was observed between MCD and MVD in OSCC and dysplasia, though were not statistically significant. These findings suggest that mast cells may up regulate angiogenesis in OSCC. MCD and MVD may be used as indicators for disease progression.

Investigation on vascular cytotoxicity and extravascular transport of cationic polymer nanoparticles using perfusable 3D microvessel model.

PubMed

Ahn, Jungho; Cho, Chong-Su; Cho, Seong Woo; Kang, Joo H; Kim, Sung-Yon; Min, Dal-Hee; Song, Joon Myong; Park, Tae-Eun; Jeon, Noo Li

2018-05-25

Vascular networks are the first sites exposed to cationic polymer nanoparticles (NPs) administered intravenously, and thus function as a barrier for NPs reaching the target organ. While cationic polymer NPs have been intensively studied as non-viral delivery systems, their biological effects in human microvessels have been poorly investigated due to a lack of appropriate in vitro systems. Here, we employed a three-dimensional microvessel on a chip, which accurately models in vivo conditions. An open and perfused microvessel surrounded by pericytes was shown to reproduce the important features of living vasculature, including barrier function and biomarkers. Using this microvessel chip, we observed contraction of the microvascular lumen induced by perfused polyethylenimine (PEI)/DNA NPs. We demonstrated that the oxidative stress present when microvessels were exposed to PEI NPs led to rearrangement of microtubules resulting in microvessel contraction. Furthermore, the transcytotic behavior of PEI NPs was analyzed in the microvessel by monitoring the escape of PEI NPs from the microvascular lumen into the perivascular region, which was not possible in two-dimensional culture systems. With our new understanding of the different behaviors of cationic polymer NPs depending on their transcytotic route, we suggest that caveolae-mediated transcytosis is a powerful route for efficient extravascular transport. Microvascular networks are not only biological system constituting largest surface area in the body and but also first site exposed to nanoparticle in vivo. While cationic polymer NPs have been intensively studied as non-viral delivery systems, its biological effects in human microvessel have been poorly investigated due to lack of appropriate in vitro systems. Here, we microengineered an open and perfused 3D pericyte incorporated microvessel model which possesses same morphological characteristic of in vivo. Using the microengineered model, this study represents the first report of transcytotic behavior of NPs in 3D microvessel, and its effect on extravasation efficiency. Our study lays the groundwork for the integration of innovative technologies to examine blood vessel-nanoparticle interaction, which a critical but ill-defined phenomenon. Copyright © 2018. Published by Elsevier Ltd.

Evans blue dye-enhanced imaging of the brain microvessels using spectral focusing coherent anti-Stokes Raman scattering microscopy

PubMed Central

Lee, Bo-Ram; Joo, Kyung-Il; Choi, Eun Sook; Jahng, Junghoon; Kim, Hyunmin

2017-01-01

We performed dye-enhanced imaging of mouse brain microvessels using spectral focusing coherent anti-Stokes Raman scattering (SF-CARS) microscopy. The resonant signals from C-H stretching in forward CARS usually show high background intensity in tissues, which makes CARS imaging of microvessels difficult. In this study, epi-detection of back-scattered SF-CARS signals showed a negligible background, but the overall intensity of resonant CARS signals was too low to observe the network of brain microvessels. Therefore, Evans blue (EB) dye was used as contrasting agent to enhance the back-scattered SF-CARS signals. Breakdown of brain microvessels by inducing hemorrhage in a mouse was clearly visualized using backward SF-CARS signals, following intravenous injection of EB. The improved visualization of brain microvessels with EB enhanced the sensitivity of SF-CARS, detecting not only the blood vessels themselves but their integrity as well in the brain vasculature. PMID:29049299

Rhamnazin, a novel inhibitor of VEGFR2 signaling with potent antiangiogenic activity and antitumor efficacy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Yao; Department of Endocrinology and Metabolism, The Third Hospital of Nanchang, Nanchang Key Laboratory of Diabetes, No.1 Qianjing Road, Xihu District, Nanchang 330009, Jiangxi Province; Cai, Wei

Anti-angiogenesis targeting vascular endothelial growth factor receptor 2 (VEGFR2) has emerged as an important tool for cancer therapy. The identification of new drugs from natural products has a long and successful history. In this study, we described a novel VEGFR2 inhibitor, rhamnazin, which inhibits tumor angiogenesis and growth. Rhamnazin significantly inhibited proliferation, migration and tube formation of human umbilical vascular endothelial cells (HUVECs) in vitro as well as inhibited sprouts formation of rat aorta ring. In addition, it inhibited vascular endothelial growth factor (VEGF)-induced phosphorylation of VEGFR2 and its downstream signaling regulator in HUVECs. Moreover, rhamnazin could directly inhibit proliferation ofmore » breast cancer cells MDA-MB-231 in vitro and in vivo. Oral administration of rhamnazin at a dose of 200 mg/kg/day could markedly inhibited human tumor xenograft growth and decreased microvessel densities (MVD) in tumor sections. Taken together, these preclinical evaluations suggest that rhamnazin inhibits angiogenesis and may be a promising anticancer drug candidate. - Highlights: • Rhamnazin inhibits the response of HUVECs to VEGF in vitro. • Rhamnazin inhibits VEGFR2 kinase activity and its downstream signaling. • Rhamnazin prevents the growth of MDA-MB-231 tumor and reduces micro-vessel density in vivo.« less

Immunohistochemical expression of vascular endothelial growth factor in canine oral squamous cell carcinomas.

PubMed

Martano, Manuela; Restucci, Brunella; Ceccarelli, Dora Maria; Lo Muzio, Lorenzo; Maiolino, Paola

2016-01-01

Angiogenesis is crucial for the growth and metastasis of malignant tumours, and various proangiogenic factors promote this process. One of these factors is vascular endothelial growth factor (VEGF), which appears to play a key role in tumour angiogenesis. The aim of the present study was to assess whether VEGF expression is associated with angiogenesis, disease progression and neoplastic proliferation in canine oral squamous cell carcinoma (OSCC) tissue. VEGF immunoreactivity was quantified by immunohistochemistry in 30 specimens, including normal oral mucosa and OSCC tissues graded as well, moderately or poorly differentiated. VEGF expression was correlated with tumour cell proliferation, as assessed using the proliferating cell nuclear antigen (PCNA) marker and microvessel density (data already published). The present results revealed that VEGF and PCNA expression increased significantly between normal oral tissue and neoplastic tissue, and between well and moderately/poorly differentiated tumours. In addition, VEGF expression was strongly correlated with PCNA expression and microvessel density. It was concluded that VEGF may promote angiogenesis through a paracrine pathway, stimulating endothelial cell proliferation and, similarly, may induce tumour cell proliferation through an autocrine pathway. The present results suggest that the evaluation of VEGF may be a useful additional criterion for estimating malignancy and growth potential in canine OSCCs.

Continuous representation of tumor microvessel density and detection of angiogenic hotspots in histological whole-slide images.

PubMed

Kather, Jakob Nikolas; Marx, Alexander; Reyes-Aldasoro, Constantino Carlos; Schad, Lothar R; Zöllner, Frank Gerrit; Weis, Cleo-Aron

2015-08-07

Blood vessels in solid tumors are not randomly distributed, but are clustered in angiogenic hotspots. Tumor microvessel density (MVD) within these hotspots correlates with patient survival and is widely used both in diagnostic routine and in clinical trials. Still, these hotspots are usually subjectively defined. There is no unbiased, continuous and explicit representation of tumor vessel distribution in histological whole slide images. This shortcoming distorts angiogenesis measurements and may account for ambiguous results in the literature. In the present study, we describe and evaluate a new method that eliminates this bias and makes angiogenesis quantification more objective and more efficient. Our approach involves automatic slide scanning, automatic image analysis and spatial statistical analysis. By comparing a continuous MVD function of the actual sample to random point patterns, we introduce an objective criterion for hotspot detection: An angiogenic hotspot is defined as a clustering of blood vessels that is very unlikely to occur randomly. We evaluate the proposed method in N=11 images of human colorectal carcinoma samples and compare the results to a blinded human observer. For the first time, we demonstrate the existence of statistically significant hotspots in tumor images and provide a tool to accurately detect these hotspots.

Apoptosis and microvessel density in gastric cancer: correlation with tumor stage and prognosis.

PubMed

Aurello, Paolo; Bellagamba, Riccardo; Rossi Del Monte, Simone; D'Angelo, Francesco; Nigri, Giuseppe; Cicchini, Claudia; Ravaioli, Matteo; Ramacciato, Giovanni

2009-12-01

Gastric cancer remains one of the most common human malignancies with a poor prognosis. Apoptosis is known to be a programmed cell death and its inhibition is involved in the unregulated cellular growth that leads to neoplasms. Microvessel density (MVD) has been investigated as a promoting factor for angiogenesis with conflicting results about its relation to survival. The aim of our study was to search a correlation between these factors and some clinicopathological features and prognosis. Identification of apoptotic cells was performed applying the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling technique and recorded as apoptotic index (A.I.), whereas monoclonal antibodies were used for the study of MVD. A significant correlation was found between low and high A.I. and the subgroup of patients in Stages I and II (P < 0.02); 20 per cent of patients with a low A.I. showed an overall survival longer than 5 years versus 44 per cent of patients with an high A.I. (P = 0.041). High MVD was significantly related to the T stage (P = 0.036) and to a poorer 5-year overall survival (P < 0.05). Further studies are required to confirm the role of apoptosis and MVD in the development and progression of gastric cancer.

Pig but not Human Interferon-γ Initiates Human Cell-Mediated Rejection of Pig Tissue in vivo

NASA Astrophysics Data System (ADS)

Sultan, Parvez; Murray, Allan G.; McNiff, Jennifer M.; Lorber, Marc I.; Askenase, Philip W.; Bothwell, Alfred L. M.; Pober, Jordan S.

1997-08-01

Split-thickness pig skin was transplanted on severe combined immunodeficient mice so that pig dermal microvessels spontaneously inosculated with mouse microvessels and functioned to perfuse the grafts. Pig endothelial cells in the healed grafts constitutively expressed class I and class II major histocompatibility complex molecules. Major histocompatibility complex molecule expression could be further increased by intradermal injection of pig interferon-γ (IFN-γ ) but not human IFN-γ or tumor necrosis factor. Grafts injected with pig IFN-γ also developed a sparse infiltrate of mouse neutrophils and eosinophils without evidence of injury. Introduction of human peripheral blood mononuclear cells into the animals by intraperitoneal inoculation resulted in sparse perivascular mononuclear cell infiltrates in the grafts confined to the pig dermis. Injection of pig skin grafts on mice that received human peripheral blood mononuclear cells with pig IFN-γ (but not human IFN-γ or heat-inactivated pig IFN-γ ) induced human CD4+ and CD8+ T cells and macrophages to more extensively infiltrate the pig skin grafts and injure pig dermal microvessels. These findings suggest that human T cell-mediated rejection of xenotransplanted pig organs may be prevented if cellular sources of pig interferon (e.g., passenger lymphocytes) are eliminated from the graft.

Puerarin Attenuates Cerebral Damage by Improving Cerebral Microcirculation in Spontaneously Hypertensive Rats

PubMed Central

Wu, Xu-Dong; Wang, Chen; Zhang, Zhen-Ying; Fu, Yan; Liu, Feng-Ying; Liu, Xiu-Hua

2014-01-01

Puerariae Lobatae Radix (Gegen in Chinese) is the dried root of Pueraria lobata, a semiwoody, perennial, and leguminous vine native to China. Puerarin is one of the effective components of isoflavones isolated from the root of Pueraria lobata. Previous studies showed that extracts derived from the root of Pueraria lobata possessed antihypertensive effect. Our study is to investigate whether puerarin contributes to prevention of stroke by improving cerebral microcirculation in rats. Materials and Methods. Video microscopy and laser Doppler perfusion imaging on the pia mater were used to measure the diameter of microvessel and blood perfusion in 12-week old spontaneously hypertensive rats (SHRs) and age-matched normotensive WKY rats. Histological alterations were observed by hematoxylin and eosin staining, and microvessel density in cerebral tissue was measured by immunohistochemical analysis with anti-Factor VIII antibody. Cell proliferation was detected by [3H]-TdR incorporation, and activities of p42/44 mitogen activated protein kinases (p42/44 MAPKs) were detected by western blot analysis in cultured cerebral microvascular endothelial cells (MECs). Results. Intravenous injection of puerarin relaxed arterioles and increased the blood flow perfusion in the pia mater in SHRs. Puerarin treatment for 14 days reduced the blood pressure to a normal level in SHRs (P < 0.05) and increased the arteriole diameter in the pia mater significantly as compared with vehicle treatment. Arteriole remodeling, edema, and ischemia in cerebral tissue were attenuated in puerarin-treated SHRs. Microvessel density in cerebral tissue was greater with puerarin than with vehicle treatment. Puerarin-treated MECs showed greater proliferation and p42/44 MAPKs activities than vehicle treatment. Conclusions. Puerarin possesses effects of antihypertension and stroke prevention by improved microcirculation in SHRs, which results from the increase in cerebral blood perfusion both by arteriole relaxation and p42/44 MAPKs-mediated angiogenesis. PMID:24715930

Coronary Serum Obtained After Myocardial Infarction Induces Angiogenesis and Microvascular Obstruction Repair. Role of Hypoxia-inducible Factor-1A.

PubMed

Ríos-Navarro, César; Hueso, Luisa; Miñana, Gema; Núñez, Julio; Ruiz-Saurí, Amparo; Sanz, María Jesús; Cànoves, Joaquin; Chorro, Francisco J; Piqueras, Laura; Bodí, Vicente

2018-06-01

Microvascular obstruction (MVO) exerts deleterious effects following acute myocardial infarction (AMI). We investigated coronary angiogenesis induced by coronary serum and the role of hypoxia-inducible factor-1A (HIF-1A) in MVO repair. Myocardial infarction was induced in swine by transitory 90-minute coronary occlusion. The pigs were divided into a control group and 4 AMI groups: no reperfusion, 1minute, 1 week and 1 month after reperfusion. Microvascular obstruction and microvessel density were quantified. The proangiogenic effect of coronary serum drawn from coronary sinus on endothelial cells was evaluated using an in vitro tubulogenesis assay. Circulating and myocardial HIF-1A levels and the effect of in vitro blockade of HIF-1A was assessed. Compared with control myocardium, microvessel density decreased at 90-minute ischemia, and MVO first occurred at 1minute after reperfusion. Both peaked at 1 week and almost completely resolved at 1 month. Coronary serum exerted a neoangiogenic effect on coronary endothelial cells in vitro, peaking at ischemia and 1minute postreperfusion (32 ± 4 and 41 ± 9 tubes vs control: 3 ± 3 tubes; P < .01). Hypoxia-inducible factor-1A increased in serum during ischemia (5-minute ischemia: 273 ± 52 pg/mL vs control: 148 ± 48 pg/mL; P < .01) being present on microvessels of all AMI groups (no reperfusion: 67% ± 5% vs control: 15% ± 17%; P < .01). In vitro blockade of HIF-1A reduced the angiogenic response induced by serum. Coronary serum represents a potent neoangiogenic stimulus even before reperfusion; HIF-1A might be crucial. Coronary neoangiogenesis induced by coronary serum can contribute to understanding the pathophysiology of AMI. Copyright © 2017 Sociedad Española de Cardiología. Published by Elsevier España, S.L.U. All rights reserved.

Widefield in vivo spectral and fluorescence imaging microscopy of microvessel blood supply and oxygenation

NASA Astrophysics Data System (ADS)

Lee, Jennifer; Kozikowski, Raymond; Wankhede, Mamta; Sorg, Brian S.

2011-02-01

Abnormal microvascular function and angiogenesis are key components of various diseases that can contribute to the perpetuation of the disease. Several skin diseases and ophthalmic pathologies are characterized by hypervascularity, and in cancer the microvasculature of tumors is structurally and functionally abnormal. Thus, the microvasculature can be an important target for treatment of diseases characterized by abnormal microvasculature. Motivated largely by cancer research, significant effort has been devoted to research on drugs that target the microvasculature. Several vascular targeting drugs for cancer therapy are in clinical trials and approved for clinical use, and several off-label uses of these drugs have been reported for non-cancer diseases. The ability to image and measure parameters related to microvessel function preclinically in laboratory animals can be useful for development and comparison of vascular targeting drugs. For example, blood supply time measurements give information related to microvessel morphology and can be measured with first-pass fluorescence imaging. Hemoglobin saturation measurements give an indication of microvessel oxygen transport and can be measured with spectral imaging. While each measurement individually gives some information regarding microvessel function, the measurements together may yield even more information since theoretically microvessel morphology can influence microvessel oxygenation, especially in metabolically active tissue like tumors. However, these measurements have not yet been combined. In this study, we report the combination of blood supply time imaging and hemoglobin saturation imaging of microvessel networks in tumors using widefield fluorescence and spectral imaging, respectively. The correlation between the measurements in a mouse mammary tumor is analyzed.

Identifying in vivo DCE MRI markers associated with microvessel architecture and gleason grades of prostate cancer.

PubMed

Singanamalli, Asha; Rusu, Mirabela; Sparks, Rachel E; Shih, Natalie N C; Ziober, Amy; Wang, Li-Ping; Tomaszewski, John; Rosen, Mark; Feldman, Michael; Madabhushi, Anant

2016-01-01

To identify computer extracted in vivo dynamic contrast enhanced (DCE) MRI markers associated with quantitative histomorphometric (QH) characteristics of microvessels and Gleason scores (GS) in prostate cancer. This study considered retrospective data from 23 biopsy confirmed prostate cancer patients who underwent 3 Tesla multiparametric MRI before radical prostatectomy (RP). Representative slices from RP specimens were stained with vascular marker CD31. Tumor extent was mapped from RP sections onto DCE MRI using nonlinear registration methods. Seventy-seven microvessel QH features and 18 DCE MRI kinetic features were extracted and evaluated for their ability to distinguish low from intermediate and high GS. The effect of temporal sampling on kinetic features was assessed and correlations between those robust to temporal resolution and microvessel features discriminative of GS were examined. A total of 12 microvessel architectural features were discriminative of low and intermediate/high grade tumors with area under the receiver operating characteristic curve (AUC) > 0.7. These features were most highly correlated with mean washout gradient (WG) (max rho = -0.62). Independent analysis revealed WG to be moderately robust to temporal resolution (intraclass correlation coefficient [ICC] = 0.63) and WG variance, which was poorly correlated with microvessel features, to be predictive of low grade tumors (AUC = 0.77). Enhancement ratio was the most robust (ICC = 0.96) and discriminative (AUC = 0.78) kinetic feature but was moderately correlated with microvessel features (max rho = -0.52). Computer extracted features of prostate DCE MRI appear to be correlated with microvessel architecture and may be discriminative of low versus intermediate and high GS. © 2015 Wiley Periodicals, Inc.

Temporal and spatial correlation of platelet-activating factor-induced increases in endothelial [Ca²⁺]i, nitric oxide, and gap formation in intact venules.

PubMed

Zhou, Xueping; He, Pingnian

2011-11-01

We have previously demonstrated that platelet-activating factor (PAF)-induced increases in microvessel permeability were associated with endothelial gap formation and that the magnitude of peak endothelial intracellular Ca(2+) concentration ([Ca(2+)](i)) and nitric oxide (NO) production at the single vessel level determines the degree of the permeability increase. This study aimed to examine whether the magnitudes of PAF-induced peak endothelial [Ca(2+)](i), NO production, and gap formation are correlated at the individual endothelial cell level in intact rat mesenteric venules. Endothelial gaps were quantified by the accumulation of fluorescent microspheres at endothelial clefts using confocal imaging. Endothelial [Ca(2+)](i) was measured on fura-2- or fluo-4-loaded vessels, and 4,5-diaminofluorescein (DAF-2) was used for NO measurements. The results showed that increases in endothelial [Ca(2+)](i), NO production, and gap formation occurred in all endothelial cells when vessels were exposed to PAF but manifested a spatial heterogeneity in magnitudes among cells in each vessel. PAF-induced peak endothelial [Ca(2+)](i) preceded the peak NO production by 0.6 min at the cellular level, and the magnitudes of NO production and gap formation linearly correlated with that of the peak endothelial [Ca(2+)](i) in each cell, suggesting that the initial levels of endothelial [Ca(2+)](i) determine downstream NO production and gap formation. These results provide direct evidence from intact venules that inflammatory mediator-induced increases in microvessel permeability are associated with the generalized formation of endothelial gaps around all endothelial cells. The spatial differences in the molecular signaling that were initiated by the heterogeneous endothelial Ca(2+) response contribute to the heterogeneity in permeability increases along the microvessel wall during inflammation.

Tortuous Microvessels Contribute to Wound Healing via Sprouting Angiogenesis.

PubMed

Chong, Diana C; Yu, Zhixian; Brighton, Hailey E; Bear, James E; Bautch, Victoria L

2017-10-01

Wound healing is accompanied by neoangiogenesis, and new vessels are thought to originate primarily from the microcirculation; however, how these vessels form and resolve during wound healing is poorly understood. Here, we investigated properties of the smallest capillaries during wound healing to determine their spatial organization and the kinetics of formation and resolution. We used intravital imaging and high-resolution microscopy to identify a new type of vessel in wounds, called tortuous microvessels. Longitudinal studies showed that tortuous microvessels increased in frequency after injury, normalized as the wound healed, and were closely associated with the wound site. Tortuous microvessels had aberrant cell shapes, increased permeability, and distinct interactions with circulating microspheres, suggesting altered flow dynamics. Moreover, tortuous microvessels disproportionately contributed to wound angiogenesis by sprouting exuberantly and significantly more frequently than nearby normal capillaries. A new type of transient wound vessel, tortuous microvessels, sprout dynamically and disproportionately contribute to wound-healing neoangiogenesis, likely as a result of altered properties downstream of flow disturbances. These new findings suggest entry points for therapeutic intervention. © 2017 The Authors.

Glucose Transporters are Abundant in Cells with "Occluding" Junctions at the Blood-Eye Barriers

NASA Astrophysics Data System (ADS)

Harik, Sami I.; Kalaria, Rajesh N.; Whitney, Paul M.; Andersson, Lars; Lundahl, Per; Ledbetter, Steven R.; Perry, George

1990-06-01

We studied the distribution of the "erythroid/brain" glucose transporter protein in the human and rat eye by immunocytochemistry with monoclonal and polyclonal antibodies to the C terminus of the human erythrocyte glucose transporter. We found intense immunocytochemical staining in the endothelium of microvessels of the retina, optic nerve, and iris but not in microvessels of the choroid, ciliary body, sclera, and other retro-orbital tissues. In addition, we found marked immunocytochemical staining of retinal pigment epithelium, ciliary body epithelium, and posterior epithelium of the iris. The common feature of all those endothelial and epithelial cells that stained intensely for the glucose transporter is the presence of "occluding" intercellular junctions, which constitute the anatomical bases of the blood-eye barriers. We propose that a high density of the glucose transporter is a biochemical concomitant of epithelial and endothelial cells with barrier characteristics, at least in tissues that have a high metabolic requirement for glucose.

Chitosan nanoparticles inhibit the growth of human hepatocellular carcinoma xenografts through an antiangiogenic mechanism.

PubMed

Xu, Yinglei; Wen, Zhengshun; Xu, Zirong

2009-12-01

Chitosan nanoparticles (CNP) have demonstrated anticancer activity in vitro and in vivo by a few recent researches. However, the mechanisms involved in their potential anticancer activity remain to be elucidated. In this study, the effects of CNP on tumor growth were investigated using a model of nude mice xenografted with human hepatocellular carcinoma (HCC) (BEL-7402) cells. The results demonstrated that the treatment of these nude mice with CNP significantly inhibited tumor growth and induced tumor necrosis. Furthermore, microvessel density (MVD) determination by counting immunohistologically stained tumor microvessels suggested that CNP dose-dependent tumor suppression was correlated with the inhibition of tumor angiogenesis. Mechanistically, immunohistochemical and quantitative real-time reverse transcription-polymerase reaction assays provided evidence that CNP-mediated inhibition of tumor angiogenesis was linked to impaired levels of vascular endothelial growth factor receptor 2 (VEGFR2). Due to their low or non-toxicity, CNP and their derivatives may represent a novel class of anti-cancer drug.

Non-Invasive Markers of Tumor Growth, Metastases, and Sensitivity to Anti-Neoplastic Therapy

DTIC Science & Technology

2009-01-01

angiogenic agents. Validation of the results of the treatment studies will be based on tumor growth, metastases, and microvessel density...detectable by NMR. DCE-MRI studies do not suggest differences in vascular parameters between slow and fast growing rat prostate tumors. The R3327AT...Introduction The primary goal of this study is to determine whether non-invasive magnetic resonance (MR) techniques can distinguish between slow and

COX-2 and Prostate Cancer Angiogenesis

DTIC Science & Technology

2001-03-01

the optimal dosing and timing of a COX-2 inhibitor (NS398) in an animal model of human prostate cancer, (2)and (3) the mechanisms underlying the...cancer tissues (14) and that a COX-2 inhibitor selectively induces apoptosis in a prostate cancer cell line (15). We also demonstrated that treatment of...human prostate tumor-bearing mice with a selective COX-2 inhibitor (NS-398) significantly reduces tumor size, microvessel density and levels of a

Local microcirculation disorders in uterus under laser tissue welding and their influence in the healing process

NASA Astrophysics Data System (ADS)

Kozlov, Valentine I.; Skobelkin, Oleg K.; Fatkullin, Ildar; Terman, Oleg A.; Chizhov, Gennadii; Gabidullina, Rushania

1994-12-01

To study the possibility of using Nd:YAG laser to weld the tissues of the uterus experiments in rats and dogs have been conducted. With the biomicroscopy and the laser Doppler flowmetry we have evaluated the microcirculation in the uterus wall under traditional suture and laser welding suture. As a model of the wound, the dissection of serosa and muscles of the organ wall have been used. In laser welding suture we have welded the zone of tissue about 1 mm3 with the laser (power density 270 W/cm2). Histological control has been fulfilled on various phases of the healing process. The investigation of the uterus wall demonstrates that there are zones of microcirculation disorders in tissues: (1) the zone of coagulation of microvessels and adjacent tissues (about 100 micrometers ); (2) the zone of stasis (150 - 200 micrometers ); (3) the zone of reactive-destructive changes of microvessels (300 micrometers ), (4) the zone of malfunctional microcirculatory changes (600 micrometers ). The coagulation of microvessels changes the character of inflammation and the healing process, decreases the exudation phase and the leucocyte infiltration of tissues, and accelerates the capillary growth. In contrast with traditional suture, in the case of laser welding suture the edema and hemorrhagic signs are less expressed. The complete restoration of microcirculation under laser welding suture has been observed by the fourteenth day of the healing process. Under the traditional suture method normalization of tissue nutritious blood flow has been achieved by 21 days.

Brain vascular image segmentation based on fuzzy local information C-means clustering

NASA Astrophysics Data System (ADS)

Hu, Chaoen; Liu, Xia; Liang, Xiao; Hui, Hui; Yang, Xin; Tian, Jie

2017-02-01

Light sheet fluorescence microscopy (LSFM) is a powerful optical resolution fluorescence microscopy technique which enables to observe the mouse brain vascular network in cellular resolution. However, micro-vessel structures are intensity inhomogeneity in LSFM images, which make an inconvenience for extracting line structures. In this work, we developed a vascular image segmentation method by enhancing vessel details which should be useful for estimating statistics like micro-vessel density. Since the eigenvalues of hessian matrix and its sign describes different geometric structure in images, which enable to construct vascular similarity function and enhance line signals, the main idea of our method is to cluster the pixel values of the enhanced image. Our method contained three steps: 1) calculate the multiscale gradients and the differences between eigenvalues of Hessian matrix. 2) In order to generate the enhanced microvessels structures, a feed forward neural network was trained by 2.26 million pixels for dealing with the correlations between multi-scale gradients and the differences between eigenvalues. 3) The fuzzy local information c-means clustering (FLICM) was used to cluster the pixel values in enhance line signals. To verify the feasibility and effectiveness of this method, mouse brain vascular images have been acquired by a commercial light-sheet microscope in our lab. The experiment of the segmentation method showed that dice similarity coefficient can reach up to 85%. The results illustrated that our approach extracting line structures of blood vessels dramatically improves the vascular image and enable to accurately extract blood vessels in LSFM images.

Exercise induces cerebral VEGF and angiogenesis via the lactate receptor HCAR1

PubMed Central

Morland, Cecilie; Andersson, Krister A.; Haugen, Øyvind P.; Hadzic, Alena; Kleppa, Liv; Gille, Andreas; Rinholm, Johanne E.; Palibrk, Vuk; Diget, Elisabeth H.; Kennedy, Lauritz H.; Stølen, Tomas; Hennestad, Eivind; Moldestad, Olve; Cai, Yiqing; Puchades, Maja; Offermanns, Stefan; Vervaeke, Koen; Bjørås, Magnar; Wisløff, Ulrik; Storm-Mathisen, Jon; Bergersen, Linda H.

2017-01-01

Physical exercise can improve brain function and delay neurodegeneration; however, the initial signal from muscle to brain is unknown. Here we show that the lactate receptor (HCAR1) is highly enriched in pial fibroblast-like cells that line the vessels supplying blood to the brain, and in pericyte-like cells along intracerebral microvessels. Activation of HCAR1 enhances cerebral vascular endothelial growth factor A (VEGFA) and cerebral angiogenesis. High-intensity interval exercise (5 days weekly for 7 weeks), as well as L-lactate subcutaneous injection that leads to an increase in blood lactate levels similar to exercise, increases brain VEGFA protein and capillary density in wild-type mice, but not in knockout mice lacking HCAR1. In contrast, skeletal muscle shows no vascular HCAR1 expression and no HCAR1-dependent change in vascularization induced by exercise or lactate. Thus, we demonstrate that a substance released by exercising skeletal muscle induces supportive effects in brain through an identified receptor. PMID:28534495

Exercise induces cerebral VEGF and angiogenesis via the lactate receptor HCAR1.

PubMed

Morland, Cecilie; Andersson, Krister A; Haugen, Øyvind P; Hadzic, Alena; Kleppa, Liv; Gille, Andreas; Rinholm, Johanne E; Palibrk, Vuk; Diget, Elisabeth H; Kennedy, Lauritz H; Stølen, Tomas; Hennestad, Eivind; Moldestad, Olve; Cai, Yiqing; Puchades, Maja; Offermanns, Stefan; Vervaeke, Koen; Bjørås, Magnar; Wisløff, Ulrik; Storm-Mathisen, Jon; Bergersen, Linda H

2017-05-23

Physical exercise can improve brain function and delay neurodegeneration; however, the initial signal from muscle to brain is unknown. Here we show that the lactate receptor (HCAR1) is highly enriched in pial fibroblast-like cells that line the vessels supplying blood to the brain, and in pericyte-like cells along intracerebral microvessels. Activation of HCAR1 enhances cerebral vascular endothelial growth factor A (VEGFA) and cerebral angiogenesis. High-intensity interval exercise (5 days weekly for 7 weeks), as well as L-lactate subcutaneous injection that leads to an increase in blood lactate levels similar to exercise, increases brain VEGFA protein and capillary density in wild-type mice, but not in knockout mice lacking HCAR1. In contrast, skeletal muscle shows no vascular HCAR1 expression and no HCAR1-dependent change in vascularization induced by exercise or lactate. Thus, we demonstrate that a substance released by exercising skeletal muscle induces supportive effects in brain through an identified receptor.

Growth of arterioles in chronically stimulated adult rat skeletal muscle.

PubMed

Hansen-Smith, F; Egginton, S; Hudlicka, O

1998-01-01

The purpose of this study was to test the hypothesis that capillary growth induced by chronic electrical stimulation of skeletal muscle is accompanied by the growth of small arterioles. Lower limb flexor muscles of Sprague-Dawley rats were stimulated by electrodes implanted in the vicinity of the peroneal nerve at 10 Hz for 8 h/d for 2 and 7 days. Cryostat sections from the proximal, middle, and distal regions of the extensor digitorum longus muscle (EDL) were fluorescently immunolabeled with alpha-smooth muscle actin (alpha SMA) and myosin heavy chain (MHC) to identify mature (alpha SMA and MHC-positive) and immature (alpha SMA-positive, MHC-negative) arterioles. The fluorescent derivative of the lectin Griffonia simplicifolia I (GSI) was used to identify all microvessels, including arterioles, capillaries, and venules. The number of vessels positive for GSI or alpha SMA surrounding muscle fibers was similar in all three muscle regions (proximal, middle, distal). The mean values +/- SEM for GSI-positive vessels from all regions were similar in control (4.3 +/- 0.07) and 2-day stimulated (4.7 +/- 0.08) but higher in 7-day stimulated muscles (6.7 +/- 0.1, p < 0.05), thus confirming the previous findings on capillary growth. A similar increase was found in the number of alpha SMA positive vessels < or = 10 microns outer diameter (1.3 +/- 0.09 versus 0.4 +/- 0.03 around muscle fibers in controls). The density of terminal arterioles (< or = 10 microns) was slightly but not significantly higher after 2 days of stimulation (19.5 +/- 4 versus 15.6 +/- 2 profiles/mm2 in control muscles) and significantly higher after 7 days (33 +/- 7). While a similar increase was observed in the density of preterminal arterioles > 10 microns (17 +/- 3 control, 22 +/- 3 at 2 days and 40 +/- 5 at 7 days), the density of MHC-positive vessels muscles stimulated for 7 days was unchanged. Seven-day stimulated muscle also had a fivefold higher density of microvessel profiles < or = 10 microns that were only partially surrounded by alpha SMA. This considerably exceeds the relative increase in the number of capillaries and thus supports the concept of arteriolar growth by transformation from capillaries. Chronic electrical stimulation results in an early increase in the number of immature (MHG-negative), but not mature (MHC-positive) arterioles, a process that accompanies the increase in capillarization. The great increase in the number of microvessels only partially covered by alpha SMA suggests arteriolization of capillaries as a contributing mechanism in this growth.

High eIF4E, VEGF, and Microvessel Density in Stage I to III Breast Cancer

PubMed Central

Byrnes, Kerry; White, Stephen; Chu, Quyen; Meschonat, Carol; Yu, Herbert; Johnson, Lester W.; DeBenedetti, Arrigo; Abreo, Fleurette; Turnage, Richard H.; McDonald, John C.; Li, Benjamin D.

2006-01-01

Objective: In a prospective trial, to determine if eIF4E overexpression in breast cancer specimens is correlated with VEGF elevation, increased tumor microvessel density (MVD) counts, and a worse clinical outcome irrespective of nodal status. Summary and Background Data: In vitro, the overexpression of eukaryotic initiation factor 4E (eIF4E) up-regulates the translation of mRNAs with long 5′-untranslated regions (5′-UTRs). One such gene product is the vascular endothelial growth factor (VEGF). Methods: A total of 114 stage I to III breast cancer patients were prospectively accrued and followed with a standardized clinical surveillance protocol. Cancer specimens were quantified for eIF4E, VEGF, and MVD. Outcome endpoints were cancer recurrence and cancer-related death. Results: eIF4E overexpression was found in all cancer specimens (mean ± SD, 12.5 ± 7.6-fold). Increasing eIF4E overexpression correlated with increasing VEGF elevation (r = 0.24, P = 0.01, Spearman's coefficient), and increasing MVD counts (r = 0.35, P < 0.0002). Patients whose tumor had high eIF4E overexpression had shorter disease-free survival (P = 0.004, log-rank test) and higher cancer-related deaths (P = 0.002) than patients whose tumors had low eIF4E overexpression. Patients with high eIF4E had a hazard ratio for cancer recurrence and cancer-related death of 1.8 and 2.1 times that of patients with low eIF4E (respectively, P = 0.009 and P = 0.002, Cox proportional hazard model). Conclusions: In breast cancer patients, increasing eIF4E overexpression in the cancer specimens correlates with higher VEGF levels and MVD counts. Patients whose tumors had high eIF4E overexpression had a worse clinical outcome, independent of nodal status. Thus, eIF4E overexpression in breast cancer appears to predict increased tumor vascularity and perhaps cancer dissemination by hematogenous means. PMID:16633004

Slit2 promotes tumor growth and invasion in chemically induced skin carcinogenesis.

PubMed

Qi, Cuiling; Lan, Haimei; Ye, Jie; Li, Weidong; Wei, Ping; Yang, Yang; Guo, Simei; Lan, Tian; Li, Jiangchao; Zhang, Qianqian; He, Xiaodong; Wang, Lijing

2014-07-01

Slit, a neuronal guidance cue, binds to Roundabout (Robo) receptors to modulate neuronal, leukocytic, and endothelial migration. Slit has been reported to have an important effect on tumor growth and metastasis. In the current study, we evaluated the role of Slit2 in skin tumor growth and invasion in mice using a two-step chemical carcinogenesis protocol. We found that Slit2 expression correlated with the loss of basement membrane in the samples of human skin squamous cell carcinoma at different stages of disease progression. Slit2-Tg mice developed significantly more skin tumors than wild-type mice. Furthermore, the skin tumors that occurred in Slit2-Tg mice were significantly larger than those in the wild-type mice 10 weeks after 7,12-dimethylbenz[a]anthracene initiation until the end of the experiment. We also found that pathological development of the wild-type mice was delayed compared with that of Slit2-Tg mice. To further investigate the mechanism of increasing tumors in Slit2-Tg mice, we analyzed the expression of 5-bromo-2'-deoxyuridine (BrdU) in mouse skin lesions and found that the number of BrdU-positive cells and microvessel density in skin lesions were significantly higher in Slit2-Tg mice than in wild-type mice. Histological staining of PAS and type IV collagen and the colocalization of Slit2 and type IV collagen demonstrated varying degrees of loss of the basement membrane in the skin lesions from Slit2-Tg mice that were at the stage of carcinoma in situ. However, the basement membrane was well defined in the wild-type mice. In addition, MMP2, but not MMP9, was upregulated in the skin tissue of Slit2-Tg mice. Interruption of Slit2-Robo1 signaling by the antibody R5 significantly repressed the invasive capability of the squamous cell carcinoma cell line A431. Taken together, our findings reveal that Slit2 promotes DMBA/TPA-induced skin tumorigenesis by increasing cell proliferation, microvessel density, and invasive behavior of cutaneous squamous cell carcinoma, along with loss of basement membrane, by upregulation of MMP2 expression.

Lymphatic microvessel density as a predictive marker for the recurrence time of pterygium: A three-year follow-up study

PubMed Central

Lin, Haotian; Luo, Lixia; Ling, Shiqi; Chen, Wan; Liu, Zhaochuan; Zhong, Xiaojian; Wu, Changrui; Liu, Yizhi

2013-01-01

Purpose To investigate whether lymphatic microvessel density (LMVD) could be used as a predictive marker for the recurrence time of pterygia. Methods This was a prospective case series study. Ninety-six patients with unilateral eye primary nasal pterygia were included. The patients were clinically evaluated to grade the severity of their pterygia (32 were Grade 1, 29 were Grade 2, and 35 were Grade 3) before they underwent bare sclera resection with the use of mitomycin C. Excised tissues from the 96 patients and the ten normal nasal conjunctiva obtained from age-matched donor eyeballs (controls) were immunostained with LYVE-1 and CD31 monoclonal antibodies to evaluate LMVD and blood microvessel density (BMVD). The patients were followed up for three years or until pterygium recurrence was identified, which was defined as fibrovascular regrowth past the limbus in a previously compromised area. The recurrence time (RT) for a pterygium was calculated, and its relationship with LMVD and/or BMVD was statistically analyzed. Results In total, there were 24 cases of pterygium recurrence. The recurrence rate of Grade 1 was 28.1% (9/32), Grade 2 was 24.1% (7/29), and Grade 3 was 22.9% (8/35), as classified in the primary pterygium (p>0.05); the overall recurrence rate was 25% (24/96) for all patients during the three-year follow-up. In the tissue analysis, there were a small number of CD31 (+), LYVE-1(-) BMVD and only a few CD31 (weak), LYVE-1(+) LMVD in the ten normal nasal conjunctiva tissues. BMVD and LMVD increased significantly in the pterygium tissue compared to the control tissue and were significantly correlated with the width and area of pterygium in Grades 1–3 (all p values <0.05). RT was not correlated with BMVD or pterygium grade, but LMVD was significantly and negatively correlated with RT within each group and in the total patient cohort. Furthermore, we determined that an LMVD greater than 20 in the surgical specimens predicted pterygium recurrence. Conclusions The LMVD of surgical specimens is an independent risk factor and a valuable predictive factor for the recurrence time of pterygia. PMID:23378730

[Pathologic change of elastic fibers with difference of microvessel density and expression of angiogenesis-related proteins in internal hemorrhoid tissues].

PubMed

Han, Wei; Wang, Zhen-jun; Zhao, Bo; Yang, Xin-qing; Wang, Dong; Wang, Jian-pin; Tang, Xiu-ying; Zhao, Fa; Hung, Yan-ting

2005-01-01

To investigate the pathological variations in internal hemorrhoid and evaluate the expression of nitric- oxide synthase(NOS),vascular endothelial growth factor(VEGF),matrix metalloproteinase- 2(MMP2) and MMP9. Normal anal cushion and internal hemorrhoids tissue samples were obtained from 24 patients with iii degree hemorrhoids after procedure for prolapse and hemorrhoids(PPH) procedure. The expression of NOS, VEGF, MMP2, MMP9 and CD34 were detected by immunohistochemical staining; the microvessel density (MVD) was counted by anti- CD34 antibody; the elastic fibers were detected by orcein staining. There were statistically significant differences in the expression of MVD, VEGF, MMP9 between internal hemorrhoid tissue and normal anal cushions(P< 0.05). iNOS was significantly increased in hemorrhoid tissue, but no significant difference between normal anal cushions and hemorrhoid tissue. Morphological abnormalities such as breaking, distortion, mortality, hyaline degeneration were found in elastic fibers of internal hemorrhoid tissue, but not in normal anal cushions. Angiogenesis is evident in hemorrhoid tissue, suggesting the possible mechanism in the pathogenesis of hemorrhoids. The direct degeneration effect of MMP9 on supporting structure elastic fibers in anal cushion is another important mechanism. The high expression of iNOS suggests the inflammatory factors involve in the pathogenesis of hemorrhoids, and NO may be involve in pathological effect on hemorrhoids.

Investigating the effect of tumor vascularization on magnetic targeting in vivo using retrospective design of experiment.

PubMed

Mei, Kuo-Ching; Bai, Jie; Lorrio, Silvia; Wang, Julie Tzu-Wen; Al-Jamal, Khuloud T

2016-11-01

Nanocarriers take advantages of the enhanced permeability and retention (EPR) to accumulate passively in solid tumors. Magnetic targeting has shown to further enhance tumor accumulation in response to a magnetic field gradient. It is widely known that passive accumulation of nanocarriers varies hugely in tumor tissues of different tumor vascularization. It is hypothesized that magnetic targeting is likely to be influenced by such factors. In this work, magnetic targeting is assessed in a range of subcutaneously implanted murine tumors, namely, colon (CT26), breast (4T1), lung (Lewis lung carcinoma) cancer and melanoma (B16F10). Passively- and magnetically-driven tumor accumulation of the radiolabeled polymeric magnetic nanocapsules are assessed with gamma counting. The influence of tumor vasculature, namely, the tumor microvessel density, permeability and diameter on passive and magnetic tumor targeting is assessed with the aid of the retrospective design of experiment (DoE) approach. It is clear that the three tumor vascular parameters contribute greatly to both passive and magnetically targeted tumor accumulation but play different roles when nanocarriers are targeted to the tumor with different strategies. It is concluded that tumor permeability is a rate-limiting factor in both targeting modes. Diameter and microvessel density influence passive and magnetic tumor targeting, respectively. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

A phosphodiesterase 4B-dependent interplay between tumor cells and the microenvironment regulates angiogenesis in B-cell lymphoma

PubMed Central

Suhasini, Avvaru N.; Lin, An-Ping; Bhatnagar, Harshita; Kim, Sang-Woo; Moritz, August W.; Aguiar, Ricardo C. T.

2015-01-01

Angiogenesis associates with poor outcome in diffuse large B-cell lymphoma (DLBCL), but the contribution of the lymphoma cells to this process remains unclear. Addressing this knowledge gap may uncover unsuspecting proangiogenic signaling nodes and highlight alternative antiangiogenic therapies. Here we identify the second messenger cyclic-AMP (cAMP) and the enzyme that terminates its activity, phosphodiesterase 4B (PDE4B), as regulators of B-cell lymphoma angiogenesis. We first show that cAMP, in a PDE4B-dependent manner, suppresses PI3K/AKT signals to down-modulate VEGF secretion and vessel formation in vitro. Next, we create a novel mouse model that combines the lymphomagenic Myc transgene with germline deletion of Pde4b. We show that lymphomas developing in a Pde4b-null background display significantly lower microvessel density in association with lower VEGF levels and PI3K/AKT activity. We recapitulate these observations by treating lymphoma-bearing mice with the FDA-approved PDE4 inhibitor Roflumilast. Lastly, we show that primary human DLBCLs with high PDE4B expression display significantly higher microvessel density. Here, we defined an unsuspected signaling circuitry in which the cAMP generated in lymphoma cells downmodulates PI3K/AKT and VEGF secretion to negatively influence vessel development in the microenvironment. These data identify PDE4 as an actionable antiangiogenic target in DLBCL. PMID:26503641

Flow of a circulating tumor cell and red blood cells in microvessels

NASA Astrophysics Data System (ADS)

Takeishi, Naoki; Imai, Yohsuke; Yamaguchi, Takami; Ishikawa, Takuji

2015-12-01

Quantifying the behavior of circulating tumor cells (CTCs) in the blood stream is of fundamental importance for understanding metastasis. Here, we investigate the flow mode and velocity of CTCs interacting with red blood cells (RBCs) in various sized microvessels. The flow of leukocytes in microvessels has been described previously; a leukocyte forms a train with RBCs in small microvessels and exhibits margination in large microvessels. Important differences in the physical properties of leukocytes and CTCs result from size. The dimensions of leukocytes are similar to those of RBCs, but CTCs are significantly larger. We investigate numerically the size effects on the flow mode and the cell velocity, and we identify similarities and differences between leukocytes and CTCs. We find that a transition from train formation to margination occurs when (R -a ) /tR≈1 , where R is the vessel radius, a is the cell radius, and tR is the thickness of RBCs, but that the motion of RBCs differs from the case of leukocytes. Our results also show that the velocities of CTCs and leukocytes are larger than the average blood velocity, but only CTCs move faster than RBCs for microvessels of R /a ≈1.5 -2.0 . These findings are expected to be useful not only for understanding metastasis, but also for developing microfluidic devices.

Angiogenesis and expression of vascular endothelial growth factor, tumour necrosis factor-α and hypoxia inducible factor-1α in canine renal cell carcinoma.

PubMed

Yhee, J Y; Yu, C H; Kim, J H; Im, K S; Kim, N H; Brodersen, B W; Doster, A R; Sur, J-H

2012-01-01

The aim of the present study was to determine the distribution and characteristics of microvessels in various histological types of canine renal cell carcinoma (RCC). The study compared microvessel density (MVD) and distribution of blood vessels according to histological type and evaluated the presence of angiogenesis-related proteins. Nine archival samples of canine RCC were studied. MVD was calculated as the mean number of blood vessels per mm(2). The diameter of blood vessels was calculated by determining either the length of the long axis of blood vessels (diameter(max)) or the mean distance from the centre of each blood vessel to the tunica adventia (diameter(mean)). A significant difference in MVD was evident between RCCs and normal kidneys (46.6 ± 28.0 versus 8.4 ± 2.2 microvessels/mm(2)). Diameter(max) in canine RCCs (34.1 ± 14.7 μm) was also significantly different from normal canine kidney (23.2 ± 3.4 μm). Vascular endothelial growth factor (VEGF) was expressed by tumour cells and vascular endothelial cells and tumour necrosis factor (TNF)-α expression was observed in vascular endothelial cells in both neoplastic and normal kidney. Although VEGF is involved in angiogenesis and correlates with tumour stage of development, no correlation was found between VEGF expression and MVD. Tumour-associated macrophages expressing TNF-α and hypoxia inducible factor 1α were identified in peritumoural tissue and may play an important role in angiogenesis. Copyright © 2011 Elsevier Ltd. All rights reserved.

The use of 5-fluorouracil-loaded nanobubbles combined with low-frequency ultrasound to treat hepatocellular carcinoma in nude mice.

PubMed

Li, Qiaoya; Li, Hongyang; He, Chengjun; Jing, Zhouhong; Liu, Changan; Xie, Juan; Ma, Wenwen; Deng, Huisheng

2017-11-21

This study aimed to investigate the therapeutic effects of 5-fluorouracil (5-FU)-loaded nanobubbles irradiated with low-intensity, low-frequency ultrasound in nude mice with hepatocellular carcinoma (HCC). A transplanted tumor model of HCC in nude mice was established in 40 mice, which were then randomly divided equally into four groups: group A (saline), group B (5-FU-loaded nanobubbles), group C (5-FU-loaded nanobubbles with non-low-frequency ultrasound), and group D (5-FU-loaded nanobubbles with low-frequency ultrasound). The tumor size in each mouse was observed via ultrasound before and after the treatments. Inhibition of the tumor growth in each group was compared, and survival curves were generated. Tumor tissues were removed to determine the apoptotic index using the TUNEL method and quantitative analysis. Tumor tissues with CD34-positive microvessels were observed by immunohistochemistry, and the tumor microvessel densities were calculated. The growth rate of the tumor volumes in group D was significantly slower than that in the other groups, while the tumor inhibition rates and apoptotic index in group D were significantly higher than those of the other groups. The number of microvessels staining positive for CD34 was decreased in group D. Therefore, group D presented the most significant inhibitory effects. Therefore, 5-FU-loaded nanobubbles subjected to irradiation with low-frequency ultrasound could further improve drug targeting and effectively inhibit the growth of transplanted tumors, which is expected to become an ideal drug carrier and targeted drug delivery system for the treatment of HCC in the future.

IMPACT OF CHRONIC ANTI-CHOLESTEROL THERAPY ON DEVELOPMENT OF MICROVASCULAR RAREFACTION IN THE METABOLIC SYNDROME

PubMed Central

Goodwill, Adam G.; Frisbee, Stephanie J.; Stapleton, Phoebe A.; James, Milinda E.; Frisbee, Jefferson C.

2011-01-01

Object The obese Zucker rat (OZR) model of the metabolic syndrome is partly characterized by moderate hypercholesterolemia in addition to other contributing co-morbidities. Previous results suggest that vascular dysfunction in OZR is associated with chronic reduction in vascular nitric oxide (NO) bioavailability and chronic inflammation, both frequently associated with hypercholesterolemia. As such, we evaluated the impact of chronic cholesterol reducing therapy on the development of impaired skeletal muscle arteriolar reactivity and microvessel density in OZR and its impact on chronic inflammation and NO bioavailability. Materials and Methods Beginning at 7 weeks of age, male OZR were treated with gemfibrozil, probucol, atorvastatin or simvastatin (in chow) for 10 weeks. Subsequently, plasma and vascular samples were collected for biochemical/molecular analyses, while arteriolar reactivity and microvessel network structure were assessed using established methodologies after 3, 6 and 10 weeks of drug therapy Results All interventions were equally effective at reducing total cholesterol, although only the statins also blunted the progressive reductions to vascular NO bioavailability, evidenced by greater maintenance of acetylcholine-induced dilator responses, an attenuation of adrenergic constrictor reactivity, and an improvement in agonist-induced NO production. Comparably, while minimal improvements to arteriolar wall mechanics were identified with any of the interventions, chronic statin treatment reduced the rate of microvessel rarefaction in OZR. Associated with these improvements was a striking statin-induced reduction in inflammation in OZR, such that numerous markers of inflammation were correlated with improved microvascular reactivity and density. However, using multivariate discriminant analyses, plasma RANTES, IL-10, MCP-1 and TNF-α were determined to be the strongest contributors to differences between groups, although their relative importance varied with time. Conclusions While the positive impact of chronic statin treatment on vascular outcomes in the metabolic syndrome are independent of changes to total cholesterol, and are more strongly associated with improvements to vascular NO bioavailability and attenuated inflammation, these results provide both a spatial and temporal framework for targeted investigation into mechanistic determinants of vasculopathy in the metabolic syndrome. PMID:19905967

Correlation of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine Neurotoxicity with Blood-Brain Barrier Monoamine Oxidase Activity

NASA Astrophysics Data System (ADS)

Kalaria, Rajesh N.; Mitchell, Mary Jo; Harik, Sami I.

1987-05-01

Systemic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) causes parkinsonism in humans and subhuman primates, but not in rats and many other laboratory animals; mice are intermediate in their susceptibility. Since MPTP causes selective dopaminergic neurotoxicity when infused directly into rat substantia nigra, we hypothesized that systemic MPTP may be metabolized by monoamine oxidase and/or other enzymes in rat brain capillaries and possibly other peripheral organs and thus prevented from reaching its neuronal sites of toxicity. We tested this hypothesis by assessing monoamine oxidase in isolated cerebral microvessels of humans, rats, and mice by measuring the specific binding of [3H]pargyline, an irreversible monoamine oxidase inhibitor, and by estimating the rates of MPTP and benzylamine oxidation. [3H]Pargyline binding to rat cerebral microvessels was about 10-fold higher than to human or mouse microvessels. Also, MPTP oxidation by rat brain microvessels was about 30-fold greater than by human microvessels; mouse microvessels yielded intermediate values. These results may explain, at least in part, the marked species differences in susceptibility to systemic MPTP. They also suggest the potential importance of ``enzyme barriers'' at the blood-brain interface that can metabolize toxins not excluded by structural barriers, and may provide biological bases for developing therapeutic strategies for the prevention of MPTP-induced neurotoxicity and other neurotoxic conditions including, possibly, Parkinson disease.

Expression of pERK and pAKT in human astrocytomas: correlation with IDH1-R132H presence, vascular endothelial growth factor, microvascular characteristics and clinical outcome.

PubMed

Saetta, Angelica A; Levidou, Georgia; El-Habr, Elias A; Panayotidis, Ioannis; Samaras, Vassilis; Thymara, Irene; Sakellariou, Stratigoula; Boviatsis, Efstathios; Patsouris, Efstratios; Korkolopoulou, Penelope

2011-06-01

Although pERK and pAKT are reportedly activated in various neoplasms, little information is available about their significance in astrocytomas. Paraffin-embedded tissue from 82 patients with diffuse infiltrating astrocytomas (grades II to IV) was investigated for the association of pERK and pAKT activation with clinicopathological features, vascular endothelial growth factor (VEGF), isocitrate dehydrogenase 1 and microvascular parameters. Nuclear pERK labelling index (LI) increased with increasing cytoplasmic pERK LI and nuclear and cytoplasmic pAKT LI (p = 0.0019, p = 0.0260 and p = 0.0012, respectively). Accordingly, cytoplasmic pERK increased with increasing levels of nuclear (p = 0.0001) and marginally with cytoplasmic pAKT LI (p = 0.0526). Nuclear and cytoplasmic pERK LI and nuclear pAKT LI were positively correlated with tumour histological grade (p = 0.0040, p = 0.0238 for pERK and p = 0.0004 for pAKT, respectively). VEGF expression was correlated with nuclear pERK (p = 0.0099) and nuclear pAKT LI (p = 0.0002). Interestingly, pERK cytoplasmic LI increased with microvessel calibre (p = 0.0287), whereas pAKT nuclear LI was marginally related to microvessel density (p = 0.0685). The presence of IDH1-R132H was related only to histological grade and lower microvessel calibre. Multivariate survival analysis in the entire cohort selected cytoplasmic pAKT LI (p = 0.045), histological grade, microvessel calibre (p = 0.028), patients' age, gender and surgical excision as independent predictors of survival. Moreover, in glioblastomas, pERK nuclear LI emerged as a favourable prognosticator in the presence of IDH1-R132H. pERK and pAKT in astrocytomas are interrelated and associated with tumour grade and angiogenesis. Moreover, the importance of cytoplasmic pAKT immunoexpression in patients' prognosis and nuclear pERK immunoexpression in glioblastomas is confirmed.

Retinal microvascular network alterations: potential biomarkers of cerebrovascular and neural diseases.

PubMed

Cabrera DeBuc, Delia; Somfai, Gabor Mark; Koller, Akos

2017-02-01

Increasing evidence suggests that the conditions of retinal microvessels are indicators to a variety of cerebrovascular, neurodegenerative, psychiatric, and developmental diseases. Thus noninvasive visualization of the human retinal microcirculation offers an exceptional opportunity for the investigation of not only the retinal but also cerebral microvasculature. In this review, we show how the conditions of the retinal microvessels could be used to assess the conditions of brain microvessels because the microvascular network of the retina and brain share, in many aspects, standard features in development, morphology, function, and pathophysiology. Recent techniques and imaging modalities, such as optical coherence tomography (OCT), allow more precise visualization of various layers of the retina and its microcirculation, providing a "microscope" to brain microvessels. We also review the potential role of retinal microvessels in the risk identification of cerebrovascular and neurodegenerative diseases. The association between vision problems and cerebrovascular and neurodegenerative diseases, as well as the possible role of retinal microvascular imaging biomarkers in cerebrovascular and neurodegenerative screening, their potentials, and limitations, are also discussed. Copyright © 2017 the American Physiological Society.

Deregulation of DNA-dependent protein kinase catalytic subunit contributes to human hepatocarcinogenesis development and has a putative prognostic value.

PubMed

Evert, M; Frau, M; Tomasi, M L; Latte, G; Simile, M M; Seddaiu, M A; Zimmermann, A; Ladu, S; Staniscia, T; Brozzetti, S; Solinas, G; Dombrowski, F; Feo, F; Pascale, R M; Calvisi, D F

2013-11-12

The DNA-repair gene DNA-dependent kinase catalytic subunit (DNA-PKcs) favours or inhibits carcinogenesis, depending on the cancer type. Its role in human hepatocellular carcinoma (HCC) is unknown. DNA-dependent protein kinase catalytic subunit, H2A histone family member X (H2AFX) and heat shock transcription factor-1 (HSF1) levels were assessed by immunohistochemistry and/or immunoblotting and qRT-PCR in a collection of human HCC. Rates of proliferation, apoptosis, microvessel density and genomic instability were also determined. Heat shock factor-1 cDNA or DNA-PKcs-specific siRNA were used to explore the role of both genes in HCC. Activator protein 1 (AP-1) binding to DNA-PKcs promoter was evaluated by chromatin immunoprecipitation. Kaplan-Meier curves and multivariate Cox model were used to study the impact on clinical outcome. Total and phosphorylated DNA-PKcs and H2AFX were upregulated in HCC. Activated DNA-PKcs positively correlated with HCC proliferation, genomic instability and microvessel density, and negatively with apoptosis and patient's survival. Proliferation decline and massive apoptosis followed DNA-PKcs silencing in HCC cell lines. Total and phosphorylated HSF1 protein, mRNA and activity were upregulated in HCC. Mechanistically, we demonstrated that HSF1 induces DNA-PKcs upregulation through the activation of the MAPK/JNK/AP-1 axis. DNA-dependent protein kinase catalytic subunit transduces HSF1 effects in HCC cells, and might represent a novel target and prognostic factor in human HCC.

Evaluation of mast cell counts and microvessel density in reactive lesions of the oral cavity.

PubMed

Kouhsoltani, Maryam; Moradzadeh Khiavi, Monir; Tahamtan, Shabnam

2016-01-01

Background. Reliable immunohistochemical assays to assess the definitive role of mast cells (MCs) and angiogenesis in the pathogenesis of oral reactive lesions are generally not available. The aim of the present study was to evaluate mast cell counts (MCC) and microvessel density (MVD) in oral reactive lesions and determine the correlation between MCC and MVD. Methods. Seventy-five cases of reactive lesions of the oral cavity, including pyogenic granuloma, fibroma, peripheral giant cell granuloma, inflammatory fibrous hyperplasia, peripheral ossifying fibroma (15 for each category) were immunohisto-chemically stained with MC tryptase and CD31. Fifteen cases of normal gingival tissue were considered as the control group. The mean MCC and MVD in superficial and deep connective tissues were assessed and total MCC and MVD was computed for each lesion. Results . Statistically significant differences were observed in MCC and MVD between the study groups (P < 0.001). MC tryptase and CD31 expression increased in the superficial connective tissue of each lesion in comparison to the deep con-nective tissue. A significant negative correlation was not found between MCC and MVD in oral reactive lesions (P < 0.001, r = -0.458). Conclusion. Although MCs were present in the reactive lesions of the oral cavity, a direct correlation between MCC and MVD was not found in these lesions. Therefore, a significant interaction between MCs and endothelial cells and an active role for MCs in the growth of oral reactive lesions was not found in this study.

ALK1 expression in oral lichen planus: a possible relation to microvessel density.

PubMed

Hazzaa, Hala H A; El-Wakeel, Naglaa M; Attia, Enas A S; Abo Hager, Eman A

2016-05-01

To assess the expression of activin receptor-like kinase 1 (ALK1) and investigate its possible relationship with microvessel density (MVD) in different forms of oral lichen planus (OLP) compared to controls' biopsies. Biopsies from 20 reticular/papular OLP (R/PLP), 20 atrophic/erosive OLP (A/ELP) patients, and 20 healthy subjects were immunohistochemically analyzed and statistically compared and correlated for ALK1 expression and MVD as assessed by CD34 expression. All OLP specimens revealed the presence of positive cytoplasmic CD34 immunostaining in endothelial cells, with statistically high significant MVD in each of R/PLP (Median; M = 4.40) and A/ELP (M = 7.69) compared to controls (M = 1.16) (P < 0.001). Statistically significant MVD was found in A/ELP compared to R/PLP (P < 0.001). All control specimens revealed negative ALK1 immunostaining of the few inflammatory cells found, while 85% of A/ELP cases and 70% of R/PLP cases showed positively immunostained sections for ALK-1, with statistically significant higher ALK1 expression In A/ELP (M = 1.95) compared to R/PLP (M = 0.86) (P = 0.005). No significant correlation between CD34 and ALK1 was detected in R/PLP (r = 0.081), while a barely moderate positive correlation was found in A/ELP (r = 0.396). ALK1 expression and MVD are increased in OLP, particularly in A/ELP type. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Sublingual microcirculatory alterations in cirrhotic patients.

PubMed

Gonzalez Ballerga, Esteban; Pozo, Mario O; Rubatto Birri, Paolo N; Kanoore Edul, Vanina Siham; Sorda, Juan A; Daruich, Jorge; Dubin, Arnaldo

2018-05-01

To assess sublingual microcirculation in cirrhotic patients and its relationship to spider angiomas, complications, and outcome. Thirty-one cirrhotic patients were prospectively compared to 31 matched controls. Sublingual microcirculation was evaluated by videomicroscopy. We specifically looked for capillaries with increased RBCV, which was defined as a velocity higher than the percentile 100th of controls. Compared to controls, cirrhotic patients showed decreased total and PVD (14.4 ± 2.2 vs 16.0 ± 1.3 and 14.1 ± 2.3 vs 15.9 ± 1.6 mm/mm 2 , respectively, P < .001 for both) and increased HFI (0.64 ± 0.39 vs 0.36 ± 0.21, P = .001). They also exhibited high RBCV in 2% of the microvessels (P < .0001). Patients with MELD score ≥10 had higher RBCV than patients with score <10 (1414 ± 290 vs 1206 ± 239 μm/s, P < .05). Patients with spider angiomas showed lower vascular densities. Microcirculation did not differ between survivors and nonsurvivors. Cirrhosis is associated with microcirculatory alterations that can be easily monitored in the sublingual mucosa. Alterations included decreased density and PPV and hyperdynamic microvessels. The most striking finding, however, was the microvascular heterogeneity. Patients with spider angiomas had more severe alterations. Larger studies should clarify the relationship between microcirculatory abnormalities and outcome. © 2018 John Wiley & Sons Ltd.

The gain-of-function GLI1 transcription factor TGLI1 enhances expression of VEGF-C and TEM7 to promote glioblastoma angiogenesis.

PubMed

Carpenter, Richard L; Paw, Ivy; Zhu, Hu; Sirkisoon, Sherona; Xing, Fei; Watabe, Kounosuke; Debinski, Waldemar; Lo, Hui-Wen

2015-09-08

We recently discovered that truncated glioma-associated oncogene homolog 1 (TGLI1) is highly expressed in glioblastoma (GBM) and linked to increased GBM vascularity. The mechanisms underlying TGLI1-mediated angiogenesis are unclear. In this study, we compared TGLI1- with GLI1-expressing GBM xenografts for the expression profile of 84 angiogenesis-associated genes. The results showed that expression of six genes were upregulated and five were down-regulated in TGLI1-carrying tumors compared to those with GLI1. Vascular endothelial growth factor-C (VEGF-C) and tumor endothelial marker 7 (TEM7) were selected for further investigations because of their significant correlations with high vascularity in 135 patient GBMs. TGLI1 bound to both VEGF-C and TEM7 gene promoters. Conditioned medium from TGLI1-expressing GBM cells strongly induced tubule formation of brain microvascular endothelial cells, and the induction was prevented by VEGF-C/TEM7 knockdown. Immunohistochemical analysis of 122 gliomas showed that TGLI1 expression was positively correlated with VEGF-C, TEM7 and microvessel density. Analysis of NCBI Gene Expression Omnibus datasets with 161 malignant gliomas showed an inverse relationship between tumoral VEGF-C, TEM7 or microvessel density and patient survival. Together, our findings support an important role that TGLI1 plays in GBM angiogenesis and identify VEGF-C and TEM7 as novel TGLI1 target genes of importance to GBM vascularity.

The 15-LO-1/15-HETE system promotes angiogenesis by upregulating VEGF in ischemic brains.

PubMed

Chen, Li; Zhu, Yan-Mei; Li, Yu-Nong; Li, Peng-Yan; Wang, Di; Liu, Yu; Qu, You-Yang; Zhu, Da-Ling; Zhu, Yu-Lan

2017-09-01

Angiogenesis promotes neurobehavioral recovery after cerebral ischemic stroke. 15(S)-hydroxyeicosatetraenoic acid (15-HETE) is one of the major metabolites of arachidonic acid by 15-lipoxygenase (15-LO) and stimulates the production of vascular endothelial growth factor (VEGF), thus, inducing autocrine-mediated angiogenesis. The present study aimed to investigate the role of 15-LO/15-HETE system on VEGF expression and angiogenesis in brain ischemia. Rat cerebral arterial vascular endothelial cells were used to set up a cell injury model of oxygen-glucose deprivation and reoxygenation (OGD/R), mimicking a condition of brain ischemia. A mouse model of middle cerebral artery occlusion (MCAO) was established. Oxygen-glucose deprivation increased cellular expression of 15-LO-1 and VEGF. Transfection of 15-LO-1 siRNA depleted cells of 15-LO-1, and sequentially induced downregulation of VEGF expression; while, incubation of 15-HETE increased the expression of VEGF. Incubation of 15-HETE attenuated the reduction in cell viability induced by oxygen-glucose deprivation, and promoted cell migration, while transfection of 15-LO-1 siRNA showed an opposite effect. In animal experiments, the density of microvessels in hypoxic regions of brains was significantly increased after MCAO, while intracerebroventricular delivery of 15-LO-1 siRNA significantly reduced the density of microvessels, and downregulates VEGF expression. The results indicate that the 15-LO-1/15-HETE system promotes angiogenesis in ischemic brains by upregulation of VEGF, representing a potential target for improving neurobehavioral recovery after cerebral ischemic stroke.

Clinicopathologic and prognostic implications of progranulin in breast carcinoma.

PubMed

Li, Li-qin; Huang, Hui-lian; Ping, Jin-liang; Wang, Xiao-hong; Zhong, Jing; Dai, Li-cheng

2011-07-05

Progranulin is a newly discovered 88-kDa glycoprotein originally purified from the highly tumorigenic mouse teratoma-derived cell line PC. Its expression is closely correlated with the development and metastasis of several cancers. However, no immunohistochemical evidence currently exists to correlate progranulin expression with clinicopathologic features in breast carcinoma biopsies, and the role of progranulin as a new marker of metastatic risk and prognosis in breast cancer has not yet been studied. The aim of this study was to investigate the clinicopathologic and prognostic implications of progranulin expression in breast carcinoma and its correlation with tumor angiogenesis. Progranulin expression was determined immunohistochemically in 183 surgical specimens from patients with breast cancer and 20 tissue samples from breast fibroadenomas. The tumor angiogenesis-related biomarker, vascular endothelial growth factor was assayed and microvessel density was assessed by counting vascular endothelial cells in tumor tissues labeled with endoglin antibody. The relationship between progranulin expression and the clinicopathologic data were analyzed. Progranulin proteins were overexpressed in breast cancer. The level of progranulin expression was significantly correlated with tumor size (P = 0.004), lymph node metastasis (P < 0.001) and TNM staging (P < 0.001). High progranulin expression was associated with higher tumor angiogenesis, reflected by increased vascular endothelial growth factor expression (P < 0.001) and higher microvessel density (P = 0.002). Progranulin may be a valuable marker for assessing the metastasis and prognosis of breast cancer, and could provide the basis for new combination regimens with antiangiogenic activity.

Cyclooxygenase-2 expression in human gastric tubular adenomas and carcinomas; correlation with intratumoral microvessel density and apoptotic index.

PubMed

Honjo, Soichiro; Kase, Satoru; Osaki, Mitsuhiko; Ardyanto, Tonang Dwi; Kaibara, Nobuaki; Ito, Hisao

2004-01-01

Cyclooxygenase (COX)-2 plays an important role in carcinogenesis in various human malignancies. This study examined the relationship among COX-2 expression, angiogenesis and apoptosis in human gastric adenoma and carcinoma. We examined the expression of COX-2 in 30 tubular adenomas and 11 carcinomas, comparing it with intratumoral microvessel density (IMVD) and apoptotic index (AI) by immunohistochemistry and the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxygenin nick-end labeling (TUNEL) procedure. Immunohistochemistry demonstrated positive expression of COX-2 in 15 (50.0%) adenomas and in 50 (53.1%) carcinomas, respectively. The frequency of COX-2 expression was significantly higher in intestinal-type carcinomas than in diffuse-type, regardless of the tumor stage. The IMVD was significantly higher in the early and advanced carcinomas than in the adenomas and also higher in the COX-2-positive adenomas and carcinomas than in the negative ones. The AI was significantly higher in the adenomas than in the carcinomas and also in the COX-2-negative adenomas and intestinal-type early carcinomas than in their positive counterparts, respectively (p < 0.05). The IMVD and AI showed significant inverse correlation in both the adenomas (p=0.02, r=-0.64) and carcinomas (p=0.04, r=-0.18). COX-2 expression might be an early event in gastric tumorigenesis and provide a preferential advantage for tumor cell proliferation because of its vascular-rich microenvironment and escape from tumor cell apoptosis, especially in intestinal-type gastric carcinomas.

Angiogenesis and lymphangiogenesis as prognostic factors after therapy in patients with cervical cancer

PubMed Central

Makarewicz, Roman; Kopczyńska, Ewa; Marszałek, Andrzej; Goralewska, Alina; Kardymowicz, Hanna

2012-01-01

Aim of the study This retrospective study attempts to evaluate the influence of serum vascular endothelial growth factor C (VEGF-C), microvessel density (MVD) and lymphatic vessel density (LMVD) on the result of tumour treatment in women with cervical cancer. Material and methods The research was carried out in a group of 58 patients scheduled for brachytherapy for cervical cancer. All women were patients of the Department and University Hospital of Oncology and Brachytherapy, Collegium Medicum in Bydgoszcz of Nicolaus Copernicus University in Toruń. VEGF-C was determined by means of a quantitative sandwich enzyme immunoassay using a human antibody VEGF-C ELISA produced by Bender MedSystem, enzyme-linked immunosorbent detecting the activity of human VEGF-C in body fluids. The measure for the intensity of angiogenesis and lymphangiogenesis in immunohistochemical reactions is the number of blood vessels within the tumour. Statistical analysis was done using Statistica 6.0 software (StatSoft, Inc. 2001). The Cox proportional hazards model was used for univariate and multivariate analyses. Univariate analysis of overall survival was performed as outlined by Kaplan and Meier. In all statistical analyses p < 0.05 (marked red) was taken as significant. Results In 51 patients who showed up for follow-up examination, the influence of the factors of angiogenesis, lymphangiogenesis, patients’ age and the level of haemoglobin at the end of treatment were assessed. Selected variables, such as patients’ age, lymph vessel density (LMVD), microvessel density (MVD) and the level of haemoglobin (Hb) before treatment were analysed by means of Cox logical regression as potential prognostic factors for lymph node invasion. The observed differences were statistically significant for haemoglobin level before treatment and the platelet number after treatment. The study revealed the following prognostic factors: lymph node status, FIGO stage, and kind of treatment. No statistically significant influence of angiogenic and lymphangiogenic factors on the prognosis was found. Conclusion Angiogenic and lymphangiogenic factors have no value in predicting response to radiotherapy in cervical cancer patients. PMID:23788848

Biological basis and pathological relevance of microvascular thrombosis.

PubMed

Pfeiler, Susanne; Massberg, Steffen; Engelmann, Bernd

2014-05-01

Microvascular thrombosis indicates a pathological occlusion of microvessels by fibrin- and/or platelet-rich thrombi. It is observed during systemic infections, cancer, myocardial infarction, stroke, neurodegenerative diseases and in thrombotic microangiopathies. Microvessel thrombosis can cause greatly differing symptoms that range from limited changes in plasma coagulation markers to severe multi-organ failure. Because microvessel thrombi are difficult to detect and often occur only transiently, their importance for disease development and host biology is likely markedly under-appreciated. Recently, clear indications for a biological basis of microvascular thrombosis have been obtained. During systemic infections microvessel thrombosis can mediate an intravascular innate immune response (immunothrombosis). This biological form of thrombosis is based on the generation of fibrin inside blood vessels and is critically triggered by neutrophils and their interactions with platelets which result in the release of neutrophil extracellular traps (extracellular nucleosomes). Immunothrombosis is critically supported by neutrophil elastase and the activator molecules of blood coagulation tissue factor and factor XII. Identification of the biological driving forces of microvascular thrombosis should help to elucidate the mechanisms promoting pathological vessel occlusions in both microvessels and large vessels. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nonendothelial source of nitric oxide in arterioles but not in venules: alternative source revealed in vivo by diaminofluorescein microfluorography.

PubMed

Kashiwagi, Satoshi; Kajimura, Mayumi; Yoshimura, Yasunori; Suematsu, Makoto

2002-12-13

This study aimed to examine topographic distribution of microvascular NO generation in vivo. To this end, nitrosonium ion (NO+)-sensitive diaminofluorescein diacetate was superfused continuously on the rat mesentery and the fluorescence was visualized in the microvessels through laser confocal microfluorography. Two major sites exhibited a time-dependent elevation of the fluorescence: microvascular endothelia and mast cells. As judged by the fluorescence sensitivity to local application of different inhibitors of NO synthase (NOS), NO availability in arteriolar endothelium and mast cells appeared to be maintained mainly by NOS1, whereas that in venular endothelium greatly depends on NOS3. In venules, the magnitude of inhibitory responses elicited by the inhibitors was positively correlated with the density of leukocyte adhesion. NOS inhibitors significantly reduced, but did not eliminate, the NO+-associated fluorescence in arterioles, capillaries, and venules, suggesting alternative sources of NO in circulation for these microvessels. Immunohistochemistry for NOS isozymes revealed that NOS1 occurred not only in nerve fibers innervated to arterioles but also abundantly in mast cells. Laser flow cytometry of peritoneal cells in vitro revealed abundant expression of NOS1 in mast cells. Interestingly, NOS3 occurred in endothelia of capillaries and venules but not in those of distal arterioles with comparable diameters. These results suggest that the arterioles receive NO from nonendothelial origins involving NOS1 present in nerve terminals and mast cells, whereas venules depend on the endothelial NOS as a major source. Furthermore, nonenzymatic sources of NO from circulating reservoirs constitute a notable fraction throughout different classes of microvessels. The full text of this article is available at http://www.circresaha.org.

Multimodal optical imaging of microvessel network convective oxygen transport dynamics.

PubMed

Dedeugd, Casey; Wankhede, Mamta; Sorg, Brian S

2009-04-01

Convective oxygen transport by microvessels depends on several parameters, including red blood cell flux and oxygen saturation. We demonstrate the use of intravital microscopy techniques to measure hemoglobin saturations, red blood cell fluxes and velocities, and microvessel cross-sectional areas in regions of microvascular networks containing multiple vessels. With these methods, data can be obtained at high spatial and temporal resolution and correlations between oxygen transport and hemodynamic parameters can be assessed. In vivo data are presented for a mouse mammary adenocarcinoma grown in a dorsal skinfold window chamber model.

NADPH Oxidase-Mediated ROS Production Determines Insulin's Action on the Retinal Microvasculature.

PubMed

Kida, Teruyo; Oku, Hidehiro; Horie, Taeko; Matsuo, Junko; Kobayashi, Takatoshi; Fukumoto, Masanori; Ikeda, Tsunehiko

2015-10-01

To determine whether insulin induces nitric oxide (NO) formation in retinal microvessels and to examine the effects of high glucose on the formation of NO. Freshly isolated rat retinal microvessels were incubated in normal (5.5 mM) or high (20 mM) glucose with or without insulin (100 nM). The levels of insulin-induced NO and reactive oxygen species (ROS) in the retinal microvessels were determined semiquantitatively using fluorescent probes, 4,5-diaminofluorescein diacetate, and hydroethidine, respectively, and a laser scanning confocal microscope. The insulin-induced changes of NO in rat retinal endothelial cells and pericytes cultured at different glucose concentrations (5.5 and 25 mM) were determined using flow cytometry. Nitric oxide synthase (NOS) protein levels were determined by Western blot analysis; intracellular levels of ROS were determined using fluorescence-activated cell sorting (FACS) analysis of ethidium fluorescence; and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase RNA expression was quantified using real-time PCR. Exposure of microvessels to insulin under normal glucose conditions led to a significant increase in NO levels; however, this increase was significantly suppressed when the microvessels were incubated under high glucose conditions. Intracellular levels of ROS were significantly increased in both retinal microvessels and cultured microvascular cells under high glucose conditions. The expression of NOS and NADPH oxidase were significantly increased in endothelial cells and pericytes under high glucose conditions. The increased formation of NO by insulin and its suppression by high glucose conditions suggests that ROS production mediated by NADPH oxidase is important by insulin's effect on the retinal microvasculature.

A comparative study of the spatial distribution of mast cells and microvessels in the foetal, adult human thymus and thymoma.

PubMed

Raica, Marius; Cimpean, Anca Maria; Nico, Beatrice; Guidolin, Diego; Ribatti, Domenico

2010-02-01

Mast cells (MCs) are widely distributed in human and animal tissues and have been shown to play an important role in angiogenesis in normal and pathological conditions. Few data are available about the relationship between MCs and blood vessels in the normal human thymus, and there are virtually no data about their distribution and significance in thymoma. The aim of this study was to analyse the spatial distribution of MCs and microvessels in the normal foetal and adult thymus and thymoma. Twenty biopsy specimens of human thymus, including foetal and adult normal thymus and thymoma were analysed. Double staining with CD34 and mast cell tryptase was used to count both mast cells and microvessels in the same fields. Computer-assisted image analysis was performed to characterize the spatial distribution of MCs and blood vessels in selected specimens. Results demonstrated that MCs were localized exclusively to the medulla. Their number was significantly higher in thymoma specimens as compared with adult and foetal normal specimens respectively. In contrast the microvessel area was unchanged. The analysis of the spatial distribution and relationship between MCs and microvessels revealed that only in the thymoma specimens was there a significant spatial association between MCs and microvessels. Overall, these data suggest that MCs do not contribute significantly to the development of the vascular network in foetal and adult thymus, whereas in thymoma they show a close relationship to blood vessels. This could be an expression of their involvement not only in endothelial cells but also in tumour cell proliferation.

A computational model of in vitro angiogenesis based on extracellular matrix fibre orientation.

PubMed

Edgar, Lowell T; Sibole, Scott C; Underwood, Clayton J; Guilkey, James E; Weiss, Jeffrey A

2013-01-01

Recent interest in the process of vascularisation within the biomedical community has motivated numerous new research efforts focusing on the process of angiogenesis. Although the role of chemical factors during angiogenesis has been well documented, the role of mechanical factors, such as the interaction between angiogenic vessels and the extracellular matrix, remains poorly understood. In vitro methods for studying angiogenesis exist; however, measurements available using such techniques often suffer from limited spatial and temporal resolutions. For this reason, computational models have been extensively employed to investigate various aspects of angiogenesis. This paper outlines the formulation and validation of a simple and robust computational model developed to accurately simulate angiogenesis based on length, branching and orientation morphometrics collected from vascularised tissue constructs. Microvessels were represented as a series of connected line segments. The morphology of the vessels was determined by a linear combination of the collagen fibre orientation, the vessel density gradient and a random walk component. Excellent agreement was observed between computational and experimental morphometric data over time. Computational predictions of microvessel orientation within an anisotropic matrix correlated well with experimental data. The accuracy of this modelling approach makes it a valuable platform for investigating the role of mechanical interactions during angiogenesis.

Inability of immunomorphometric assessment of angiogenesis to distinguish primary versus secondary myelofibrosis.

PubMed

Sharma, Prashant; Pati, Hara Prasad; Mishra, Pravas Chandra; Dinda, Amit Kumar; Gupta, Ruchika; Sharma, Alok; Jacob, Tony George

2011-08-01

To explore the utility of bone marrow (BM) angiogenesis in differentiating primary myelofibrosis (PMF) from secondary myelofibrosis (MF). CD34 immunostaining was performed on BM biopsies from 21 PMFs, 23 non-PMF myeloproliferative neoplasms (MPN) with associated MF, 20 secondary MF samples, and 10 nonfibrotic controls. Microvessel density (MVD) and microvessel surface area (MSA), along with blood and BM findings were compared between the groups. The post-MPN MF cases included chronic myeloid leukemia-MF and polycythemia vera-MF. Etiologies of secondary MF were metastatic carcinomas, non-MPN hematologic malignancies, tuberculosis, autoimmune MF, and osteopetrosis. Megakaryocytic clustering was the most frequent and intrasinusoidal hematopoiesis the most specific feature of PMF. Higher reticulin grade, collagenization, and osteomyelosclerosis were commoner in PMF. MVD and MSA were significantly increased in fibrotic marrows regardless of etiology. Although mean MVD as well as MSA were highest in PMF, extensive overlaps among groups and marked heterogeneity in the secondary MF group rendered them of limited utility in the differential diagnosis. Enhanced angiogenesis is not entirely specific for PMF. Overlaps with secondary MF limits its differential diagnostic utility. Pathogenetically, our findings suggest that enhanced angiogenesis is a secondary paraneoplastic stromal response shared by various unrelated conditions.

Combination with third-generation bisphosphonate (YM529) and interferon-alpha can inhibit the progression of established bone renal cell carcinoma.

PubMed

Kurabayashi, Atsushi; Inoue, Keiji; Fukuhara, Hideo; Karashima, Takashi; Fukata, Satoshi; Kawada, Chiaki; Shuin, Taro; Furihata, Mutsuo

2015-08-01

The aim of this study was to investigate whether the third-generation nitrogen-containing bisphosphonate (YM529) can inhibit the progression of established bone renal cell carcinoma (RCC) and to elucidate its mechanism. Antiproliferative effect and apoptosis induction of RCC cells and mouse osteoclasts by YM529 and/or interferon-alpha (IFN-α) were evaluated in vitro using cell counting and in vivo using soft X-ray, the TUNEL method and tartrate-resistant acid phosphatase stain. For the in vivo study, male athymic BALB/cA Jc1-nu nude mice bearing human RCC cell line RBM1-IT4 cells were treated with YM529 and/or IFN-α. The biological activity of osteoclasts was evaluated using the pit formation assay. The antiangiogenetic effect by YM529 and/or IFN-α was analyzed using micro-vessel density and in situ mRNA hybridization. Osteoclast number in bone tumors was decreased in YM529-treated mouse. YM529 also inhibited osteoclast activity and proliferation in vitro, whereas basic fibroblast growth factor expressions and micro-vessel density within tumors were inhibited by IFN-α. Neither YM529 nor IFN-α alone significantly inhibited the growth of established bone metastatic tumors. Combined treatment with YM529 and IFN-α may be beneficial in patients with human RCC bone metastasis. Their effects are mediated by osteoclast recruitment inhibition and inactivation by YM529 and antiangiogenesis by IFN-α. © 2015 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

Influence of shape and dispersion media of titanium dioxide nanostructures on microvessel network and ossification.

PubMed

Freyre-Fonseca, Verónica; Medina-Reyes, Estefany I; Téllez-Medina, Darío I; Paniagua-Contreras, Gloria L; Monroy-Pérez, Eric; Vaca-Paniagua, Felipe; Delgado-Buenrostro, Norma L; Flores-Flores, José O; López-Villegas, Edgar O; Gutiérrez-López, Gustavo F; Chirino, Yolanda I

2018-02-01

Titanium dioxide nanoparticles (TiO 2 NPs) production has been used for pigment, food and cosmetic industry and more recently, shaped as belts for treatment of contaminated water, self-cleaning windows and biomedical applications. However, the toxicological data have demonstrated that TiO 2 NPs inhalation induce inflammation in in vivo models and in vitro exposure leads to cytotoxicity and DNA damage. Dermal exposure has limited adverse effects and the possible risks for implants used for tissue regeneration is still under research. Then, it has been difficult to establish a straight statement about TiO 2 NPs toxicity since route of exposure and shapes of nanoparticles play an important role in the effects. In this study we aimed to investigate the effect of three different types of TiO 2 NPs (industrial, food-grade and belts) dispersed in fetal bovine serum (FBS) and saline solution (SS) on microvessel network, angiogenesis gene expression and femur ossification using a chick embryo model after an acute exposure of NPs on the day 7 after eggs fertilization. Microvascular density of chorioallantoic membrane (CAM) was analyzed after 7days of NPs injection and vehicles induced biological effects per se. NPs dispersed in FBS or SS have slight differences in microvascular density, mainly opposite effect on angiogenesis gene expression and no effects on femur ossification for NPs dispersed in SS. Interestingly, NPs shaped as belts dramatically prevented the alterations in ossification induced by FBS used as vehicle. Copyright © 2017 Elsevier B.V. All rights reserved.

Role of endothelial-to-mesenchymal transition in the pathogenesis of central nervous system hemangioblastomas.

PubMed

Takada, Shigeki; Hojo, Masato; Takebe, Noriyoshi; Tanigaki, Kenji; Miyamoto, Susumu

2018-06-07

Hemangioblastomas (HBs) are benign vascular tumors of the central nervous system and histologically contain abundant microvessels. Therefore, they clinically exhibit vascular malformation-like characteristics. It has been described that endothelial-to-mesenchymal transition (EndMT) contributes to the pathogenesis of cerebral cavernous malformations. However, it remains unknown whether EndMT contributes to the pathogenesis of central nervous system HBs. The aim of our study was to investigate whether EndMT occurs in central nervous system HBs. Ten central nervous system HBs were immunohistochemically investigated. CD31 (an endothelial marker) and EndMT markers, such as α-smooth muscle actin (a mesenchymal marker) and CD44 (a mesenchymal stem cell marker), were expressed in the endothelial layer of microvessels in all cases. These findings suggest that endothelial cells (ECs) of microvessels in central nervous system HBs have acquired mesenchymal and stem-cell-like characteristics and undergone EndMT. In all cases, both ephrin-B2 and EphB4, which are not detected in adult normal brain vessels, were expressed in the endothelial layer of microvessels. These data suggest that ECs of microvessels in central nervous system HBs are immature or malformed cells and have both arterial and venous characteristics. This is the first report showing the possibility that EndMT contributes to the pathogenesis of central nervous system HBs. It is likely that ECs of microvessels in central nervous system HBs are immature or malformed cells and have both arterial and venous characteristics. EndMT is expected to be a new therapeutic target in central nervous system HBs. Copyright © 2018 Elsevier Inc. All rights reserved.

Gaussian beam in two-photon fluorescence imaging of rat brain microvessel

NASA Astrophysics Data System (ADS)

Shi, Lingyan; Rodríguez-Contreras, Adrián; Alfano, Robert R.

2014-12-01

The critical optical properties of a Gaussian laser beam in two-photon or multiphoton fluorescence imaging, including the beam spot size, depth of focus, and intensity profile, are investigated for spatially locating nanoscale solutes in and surrounding the microvessels of rat brain.

Mechanisms for microvascular damage induced by ultrasound-activated microbubbles

NASA Astrophysics Data System (ADS)

Chen, Hong; Brayman, Andrew A.; Evan, Andrew P.; Matula, Thomas J.

2012-10-01

To provide insight into the mechanisms of microvascular damage induced by ultrasound-activated microbubbles, experimental studies were performed to correlate microvascular damage to the dynamics of bubble-vessel interactions. High-speed photomicrography was used to record single microbubbles interacting with microvessels in ex vivo tissue, under the exposure of short ultrasound pulses with a center frequency of 1 MHz and peak negative pressures (PNP) ranging from 0.8-4 MPa. Vascular damage associated with observed bubble-vessel interactions was either indicated directly by microbubble extravasation or examined by transmission electron microscopy (TEM) analyses. As observed previously, the high-speed images revealed that ultrasound-activated microbubbles could cause distention and invagination of adjacent vessel walls, and could form liquid jets in microvessels. Vessel distention, invagination, and liquid jets were associated with the damage of microvessels whose diameters were smaller than those of maximally expanded microbubbles. However, vessel invagination appeared to be the dominant mechanism for the damage of relative large microvessels.

Mechanisms for microvascular damage induced by ultrasound-activated microbubbles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen Hong; Brayman, Andrew A.; Evan, Andrew P.

To provide insight into the mechanisms of microvascular damage induced by ultrasound-activated microbubbles, experimental studies were performed to correlate microvascular damage to the dynamics of bubble-vessel interactions. High-speed photomicrography was used to record single microbubbles interacting with microvessels in ex vivo tissue, under the exposure of short ultrasound pulses with a center frequency of 1 MHz and peak negative pressures (PNP) ranging from 0.8-4 MPa. Vascular damage associated with observed bubble-vessel interactions was either indicated directly by microbubble extravasation or examined by transmission electron microscopy (TEM) analyses. As observed previously, the high-speed images revealed that ultrasound-activated microbubbles could cause distentionmore » and invagination of adjacent vessel walls, and could form liquid jets in microvessels. Vessel distention, invagination, and liquid jets were associated with the damage of microvessels whose diameters were smaller than those of maximally expanded microbubbles. However, vessel invagination appeared to be the dominant mechanism for the damage of relative large microvessels.« less

An enhanced narrow-band imaging method for the microvessel detection

NASA Astrophysics Data System (ADS)

Yu, Feng; Song, Enmin; Liu, Hong; Wan, Youming; Zhu, Jun; Hung, Chih-Cheng

2018-02-01

A medical endoscope system combined with the narrow-band imaging (NBI), has been shown to be a superior diagnostic tool for early cancer detection. The NBI can reveal the morphologic changes of microvessels in the superficial cancer. In order to improve the conspicuousness of microvessel texture, we propose an enhanced NBI method to improve the conspicuousness of endoscopic images. To obtain the more conspicuous narrow-band images, we use the edge operator to extract the edge information of the narrow-band blue and green images, and give a weight to the extracted edges. Then, the weighted edges are fused with the narrow-band blue and green images. Finally, the displayed endoscopic images are reconstructed with the enhanced narrow-band images. In addition, we evaluate the performance of enhanced narrow-band images with different edge operators. Experimental results indicate that the Sobel and Canny operators achieve the best performance of all. Compared with traditional NBI method of Olympus company, our proposed method has more conspicuous texture of microvessel.

Ultra-high Speed Optical Imaging of Ultrasound-activated Microbubbles in Mesenteric Microvessels

NASA Astrophysics Data System (ADS)

Chen, Hong

Ultrasound contrast agent microbubbles have gained widespread applications in diagnostic and therapeutic ultrasound. Animal studies of bioeffects induced by ultrasound-activated microbubbles have demonstrated that microbubbles can cause microvessel damage. Much scientific attention has been attracted to such microvascular bioeffects, not only because of the related safety concerns, but also because of the potential useful applications of microbubbles in the intravascular delivery of drugs and genetic materials into target tissues. A significant challenge in using microbubbles in medical ultrasound is the lack of knowledge about how the microbubbles behave in blood vessels when exposed to ultrasound and how their interactions with ultrasound cause vascular damage. Although extensive studies were performed in the past to study the dynamics of microbubbles, most of those studies were performed in vitro and did not directly address the clinical environment in which microbubbles are injected into blood vessels. In this thesis work, a synchronized optical-acoustic system was set up for ultrahigh speed imaging of insonated microbubbles in microvessels. The recorded images revealed the formation of microjets penetrating the microbubbles, as well as vessel distention (motion outward against the surrounding tissue) and vessel invagination (motion inward toward the lumen) caused by the expansion and collapse of the microbubbles, respectively. Contrary to current paradigms which propose that microbubbles damage vessels either by distending them or by forming liquid jets impinging on them, microbubbles translation and jetting were in the direction away from the nearest vessel wall; furthermore, invagination typically exceeded distention in arterioles and venules. Vessel invagination was found to be associated with vascular damage. These studies suggest that vessel invagination may be a newly discovered potential mechanism for vascular damage by ultrasound-activated microbubbles. The dynamics of bubble-vessel interactions are coupled intimately with the viscoelastic properties of the microvessels. To probe these properties, a method based on the relaxation times of the invaginated microvessels was used to estimate the relaxation time constants of the microvessels. It was found that the time constants were on microsecond time scales, which provided insight into the unique and unknown viscoelastic properties of the microvessels.

[Relationship between the changes in ischemia/reperfusion cerebro-microvessel basement membrane injury and gelatinase system in senile rat].

PubMed

Li, Jian-sheng; Liu, Ke; Liu, Jing-xia; Wang, Ming-hang; Zhao, Yue-wu; Liu, Zheng-guo

2008-11-01

To study the relationship of cerebro-microvessel basement membrane injury and gelatinase system after cerebral ischemia/reperfusion (I/R) in aged rats. Cerebral I/R injury model was reproduced by intraluminal silk ligature thrombosis of the middle cerebral artery occlusion (MCAO). Rats were divided randomly into sham control and I/R groups in young rats [ischemia 3 hours (I 3 h) and reperfusion 6 hours (I/R 6 h), 12 hours (I/R 12 h), 24 hours (I/R 24 h), 3 days (I/R 3 d), 6 days (I/R 6 d)], and sham control group and I/R group in aged rats (I 3 h and I/R 6 h, I/R 12 h, I/R 24 h , I/R 3 d, I/R 6 d). The change in cerebro-cortex microvessel basement membrane structure, basement membrane type IV collagen (Col IV) and laminin (LN) contents, matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) expression in every group were determined with immunohistochemical method and zymogram analysis. With the increase in age, Col IV and LN contents of the microvessel basement membrane were increased, and MMP-2 and MMP-9 expressions were stronger. With prolongation of I/R, the degradation of microvessel basement membrane components (Col IV and LN) was positively correlated with the duration of cerebral I/R. MMP-2 expression was increased gradually, and MMP-9 and TIMP-1 expression increased at the beginning and decreased subsequently. Col IV(I 3 h, I/R 6 h , I/R 12 h), LN (I 3 h, I/R 6-24 h), MMP-2 (I 3 h, I/R 6 h-6 d) and MMP-9 (I 3 h, I/R 6-24 h) expression level in aged rats with I/R injury were higher, and TIMP-1 (I/R 24 h) expression was lower than those in young rats (P<0.05 or P<0.01). In addition, changes in MMP-2 and MMP-9 contents as determined by zymogram analysis method coincided with their immunoexpression. With the increase of age, alteration in membrane components of cerebro-microvessel basement membrane in rats is related with MMPs and TIMP. Cerebro-microvessel basement membrane injury is more serious in aged rats than that of young rats. Changes in cerebro-microvessel basement membrane injury in aged rats is related with gelatinase system change.

[Mesh structure of two-dimensional tumor microvascular architecture phenotype heterogeneity in non-small cell lung cancer].

PubMed

Xiong, Zeng; Zhou, Hui; Liu, Jin-Kang; Hu, Cheng-Ping; Zhou, Mo-Ling; Xia, Yu; Zhou, Jian-Hua

2009-11-01

To investigate the structural characteristics and clinical significance of two-dimensional tumor microvascular architecture phenotype (2D-TMAP) in non-small cell lung cancer (NSCLC). Thirty surgical specimens of NSCLC were collected. The sections of the tumor tissues corresponding to the slice of CT perfusion imaging were selected to construct the 2D-TMAP expression. Spearman correlation analysis was used to examine the relation between the 2D-TMAP expression and the clinicopathological features of NSCLC. A heterogeneity was noted in the 2D-TMAP expression of NSCLC. The microvascular density (MVD) in the area surrounding the tumor was higher than that in the central area, but the difference was not statistically significant. The density of the microvessels without intact lumen was significantly greater in the surrounding area than in the central area (P=0.030). The total MVD was not correlated to tumor differentiation (r=0.042, P=0.831). The density of the microvessels without intact lumen in the surrounding area was positively correlated to degree of tumor differentiation and lymph node metastasis (r=0.528 and 0.533, P=0.041 and 0.028, respectively), and also to the expressions of vascular endothelial growth factor (VEGF), ephrinB2, EphB4, and proliferating cell nuclear antigen (PCNA) (r=0.504, 0.549, 0.549, and 0.370; P=0.005, 0.002, 0.002, and 0.048, respectively). The degree of tumor differentiation was positively correlated to PCNA and VEGF expression (r=0.604 and 0.370, P=0.001 and 0.048, respectively), but inversely to the integrity of microvascular basement membrane (r=-0.531, P=0.033). The 2D-TMAP suggests the overall state of the micro-environment for tumor growth. The 2D-TMAP of NSCLC regulates angiogenesis and tumor cell proliferation through a mesh-like structure, and better understanding of the characteristics and possible mechanism of 2D-TMAP expression can be of great clinical importance.

Naringin inhibits vascular endothelial cell apoptosis via endoplasmic reticulum stress- and mitochondrial-mediated pathways and promotes intraosseous angiogenesis in ovariectomized rats

PubMed Central

Li, Zhan-Chun; Tang, Lu-Min; Shao, Jiang; Li, He

2017-01-01

In this study, to investigate the effects of naringin on vascular endothelial cell (VEC) function, proliferation, apoptosis, and angiogenesis, rat VECs were cultured in vitro and randomly divided into four groups: control, serum-starved, low-concentration naringin treatment, and high-concentration naringin treatment. MTT assay was used to detect cell proliferation while Hoechst 33258 staining and flow cytometry were used to detect apoptosis. Changes in the expression of apoptosis-associated proteins [GRP78, CHOP, caspase-12, and cytochrome c (Cyt.c)] were detected using western blotting. JC-1 staining was employed to detect changes in mitochondrial membrane potential. Intracellular caspase-3, -8, and -9 activity was determined by spectrophotometry. ELISA was used to detect endothelin (ET), and a Griess assay was used to detect changes in the expression of nitric oxide (NO) in culture medium. The study further divided an ovariectomized (OVX) rat model of osteoporosis randomly into four groups: OVX, sham-operated, low-concentration naringin treatment (100 mg/kg), and high-concentration naringin treatment (200 mg/kg). After 3 months of treatment, changes in serum ET and NO expression, bone mineral density (BMD), and microvessel density of the distal femur (using CD34 labeling of VECs) were determined. At each concentration, naringin promoted VEC proliferation in a time- and dose-dependent manner. Naringin also significantly reduced serum starvation-induced apoptosis in endothelial cells, inhibited the expression of GRP78, CHOP, caspase-12, and Cyt.c proteins, and reduced mitochondrial membrane potential as well as reduced the activities of caspase-3 and -9. Furthermore, naringin suppressed ET in vitro and in vivo while enhancing NO synthesis. Distal femoral microvascular density assessment showed that the naringin treatment groups had a significantly higher number of microvessels than the OVX group, and that microvascular density was positively correlated with BMD. In summary, naringin inhibits apoptosis in VECs by blocking the endoplasmic reticulum (ER) stress- and mitochondrial-mediated pathways. Naringin also regulates endothelial cell function and promotes angiogenesis to exert its anti-osteoporotic effect. PMID:29039439

Naringin inhibits vascular endothelial cell apoptosis via endoplasmic reticulum stress‑ and mitochondrial‑mediated pathways and promotes intraosseous angiogenesis in ovariectomized rats.

PubMed

Shangguan, Wen-Ji; Zhang, Yue-Hui; Li, Zhan-Chun; Tang, Lu-Min; Shao, Jiang; Li, He

2017-12-01

In this study, to investigate the effects of naringin on vascular endothelial cell (VEC) function, proliferation, apoptosis, and angiogenesis, rat VECs were cultured in vitro and randomly divided into four groups: control, serum‑starved, low‑concentration naringin treatment, and high‑concentration naringin treatment. MTT assay was used to detect cell proliferation while Hoechst 33258 staining and flow cytometry were used to detect apoptosis. Changes in the expression of apoptosis‑associated proteins [GRP78, CHOP, caspase‑12, and cytochrome c (Cyt.c)] were detected using western blotting. JC‑1 staining was employed to detect changes in mitochondrial membrane potential. Intracellular caspase‑3, ‑8, and ‑9 activity was determined by spectrophotometry. ELISA was used to detect endothelin (ET), and a Griess assay was used to detect changes in the expression of nitric oxide (NO) in culture medium. The study further divided an ovariectomized (OVX) rat model of osteoporosis randomly into four groups: OVX, sham‑operated, low‑concentration naringin treatment (100 mg/kg), and high‑concentration naringin treatment (200 mg/kg). After 3 months of treatment, changes in serum ET and NO expression, bone mineral density (BMD), and microvessel density of the distal femur (using CD34 labeling of VECs) were determined. At each concentration, naringin promoted VEC proliferation in a time‑ and dose‑dependent manner. Naringin also significantly reduced serum starvation‑induced apoptosis in endothelial cells, inhibited the expression of GRP78, CHOP, caspase‑12, and Cyt.c proteins, and reduced mitochondrial membrane potential as well as reduced the activities of caspase‑3 and ‑9. Furthermore, naringin suppressed ET in vitro and in vivo while enhancing NO synthesis. Distal femoral microvascular density assessment showed that the naringin treatment groups had a significantly higher number of microvessels than the OVX group, and that microvascular density was positively correlated with BMD. In summary, naringin inhibits apoptosis in VECs by blocking the endoplasmic reticulum (ER) stress‑ and mitochondrial‑mediated pathways. Naringin also regulates endothelial cell function and promotes angiogenesis to exert its anti‑osteoporotic effect.

Stereology techniques in radiation biology

NASA Technical Reports Server (NTRS)

Kubinova, Lucie; Mao, XiaoWen; Janacek, Jiri; Archambeau, John O.; Nelson, G. A. (Principal Investigator)

2003-01-01

Clinicians involved in conventional radiation therapy are very concerned about the dose-response relationships of normal tissues. Before proceeding to new clinical protocols, radiation biologists involved with conformal proton therapy believe it is necessary to quantify the dose response and tolerance of the organs and tissues that will be irradiated. An important focus is on the vasculature. This presentation reviews the methodology and format of using confocal microscopy and stereological methods to quantify tissue parameters, cell number, tissue volume and surface area, and vessel length using the microvasculature as a model tissue. Stereological methods and their concepts are illustrated using an ongoing study of the dose response of the microvessels in proton-irradiated hemibrain. Methods for estimating the volume of the brain and the brain cortex, the total number of endothelial cells in cortical microvessels, the length of cortical microvessels, and the total surface area of cortical microvessel walls are presented step by step in a way understandable for readers with little mathematical background. It is shown that stereological techniques, based on a sound theoretical basis, are powerful and reliable and have been used successfully.

The expression of pigment epithelium-derived factor in bladder transitional cell carcinoma.

PubMed

Jang, Tae Jung; Kim, Sung Woo; Lee, Kyung Seop

2012-06-01

Pigment epithelium-derived factor (PEDF) is an anti-angiogenic factor. The purpose of this study is to examine the involvement of PEDF in the angiogenesis and biological behavior of bladder transitional cell carcinoma (TCC). We examined the expression of PEDF in 99 bladder TCCs and ten non-neoplastic tissues, and evaluated microvessel density (MVD). The positive immunoreactivity for PEDF was seen in normal urothelium in 60% (6/10) and TCC in 13% (13/99). The PEDF expression had a significant correlation with MVD, i.e., a low MVD in 42% (5/12), a middle MVD in 11% (8/76) and a high MVD 0% (0/11) of tumors. The PEDF expression was not significantly correlated with the differentiation and invasion of TCC, but the degree of MVD was significantly higher in both high grade TCC and the pT2 tumors. The degree of PEDF expression is significantly higher in normal bladder urothelium than bladder TCC; it is inversely correlated with the angiogenesis; and it is not related to the differentiation and progression of TCC. It can therefore be concluded that bladder TCC would initially occur if there is a lack of the PEDF expression.

The Expression of Pigment Epithelium-Derived Factor in Bladder Transitional Cell Carcinoma

PubMed Central

Kim, Sung Woo; Lee, Kyung Seop

2012-01-01

Background Pigment epithelium-derived factor (PEDF) is an anti-angiogenic factor. The purpose of this study is to examine the involvement of PEDF in the angiogenesis and biological behavior of bladder transitional cell carcinoma (TCC). Methods We examined the expression of PEDF in 99 bladder TCCs and ten non-neoplastic tissues, and evaluated microvessel density (MVD). Results The positive immunoreactivity for PEDF was seen in normal urothelium in 60% (6/10) and TCC in 13% (13/99). The PEDF expression had a significant correlation with MVD, i.e., a low MVD in 42% (5/12), a middle MVD in 11% (8/76) and a high MVD 0% (0/11) of tumors. The PEDF expression was not significantly correlated with the differentiation and invasion of TCC, but the degree of MVD was significantly higher in both high grade TCC and the pT2 tumors. Conclusions The degree of PEDF expression is significantly higher in normal bladder urothelium than bladder TCC; it is inversely correlated with the angiogenesis; and it is not related to the differentiation and progression of TCC. It can therefore be concluded that bladder TCC would initially occur if there is a lack of the PEDF expression. PMID:23110012

Tc17 cells in patients with uterine cervical cancer.

PubMed

Zhang, Yan; Hou, Fei; Liu, Xin; Ma, Daoxin; Zhang, Youzhong; Kong, Beihua; Cui, Baoxia

2014-01-01

The existence of Tc17 cells was recently shown in several types of infectious and autoimmune diseases, but their distribution and functions in uterine cervical cancer (UCC) have not been fully elucidated. The frequency of Tc17 cells in peripheral blood samples obtained from UCC patients, cervical intraepithelial neoplasia (CIN) patients and healthy controls was determined by flow cytometry. Besides, the prevalence of Tc17 cells and their relationships to Th17 cells and Foxp3-expressing T cells as well as microvessels in tissue samples of the patients were assessed by immunohistochemistry staining. Compared to controls, patients with UCC or CIN had a higher proportion of Tc17 cells in both peripheral blood and cervical tissues, but the level of Tc17 cells in UCC tissues was significantly higher than that in CIN tissues. Besides, the increased level of Tc17 in UCC patients was associated with the status of pelvic lymph node metastases and increased microvessel density. Finally, significant correlations of infiltration between Tc17 cells and Th17 cells or Foxp3-expressing T cells were observed in UCC and CIN tissues. This study indicates that Tc17 cell infiltration in cervical cancers is associated with cancer progression accompanied by increased infiltrations of Th17 cells and regulatory T cells as well as promoted tumor vasculogenesis.

Parecoxib: an enhancer of radiation therapy for colorectal cancer.

PubMed

Xiong, Wei; Li, Wen-Hui; Jiang, Yong-Xin; Liu, Shan; Ai, Yi-Qin; Liu, Rong; Chang, Li; Zhang, Ming; Wang, Xiao-Li; Bai, Han; Wang, Hong; Zheng, Rui; Tan, Jing

2015-01-01

To study the effect of parecoxib, a novel cyclooxygenase-2 selective inhibitor, on the radiation response of colorectal cancer (CRC) cells and its underlying mechanisms. Both in vitro colony formation and apoptosis assays as well as in vivo mouse xenograft experiments were used to explore the radiosensitizing effects of parecoxib in human HCT116 and HT29 CRC cells. Parecoxib sensitized CRC cells to radiation in vitro with a sensitivity enhancement ratio of 1.32 for HCT116 cells and 1.15 for HT29 cells at a surviving fraction of 0.37. This effect was partially attributable to enhanced apoptosis induction by parecoxib combined with radiation, as illustrated using an in vitro apoptosis assays. Parecoxib augmented the tumor response of HCT116 xenografts to radiation, achieving growth delay more than 20 days and an enhancement factor of 1.53. In accordance with the in vitro results, parecoxib combined with radiation resulted in less proliferation and more apoptosis in tumors than radiation alone. Radiation monotherapy decreased microvessel density (MVD) and microvessel intensity (MVI), but increased the hypoxia level in xenografts. Parecoxib did not affect MVD, but it increased MVI and attenuated hypoxia. Parecoxib can effectively enhance radiation sensitivity in CRC cells through direct effects on tumor cells and indirect effects on tumor vasculature.

Smooth muscle‐generated methylglyoxal impairs endothelial cell‐mediated vasodilatation of cerebral microvessels in type 1 diabetic rats

PubMed Central

Alomar, Fadhel; Singh, Jaipaul; Jang, Hee‐Seong; Rozanzki, George J; Shao, Chun Hong; Padanilam, Babu J; Mayhan, William G

2016-01-01

Background and Purpose Endothelial cell‐mediated vasodilatation of cerebral arterioles is impaired in individuals with Type 1 diabetes (T1D). This defect compromises haemodynamics and can lead to hypoxia, microbleeds, inflammation and exaggerated ischaemia‐reperfusion injuries. The molecular causes for dysregulation of cerebral microvascular endothelial cells (cECs) in T1D remains poorly defined. This study tests the hypothesis that cECs dysregulation in T1D is triggered by increased generation of the mitochondrial toxin, methylglyoxal, by smooth muscle cells in cerebral arterioles (cSMCs). Experimental Approach Endothelial cell‐mediated vasodilatation, vascular transcytosis inflammation, hypoxia and ischaemia‐reperfusion injury were assessed in brains of male Sprague‐Dawley rats with streptozotocin‐induced diabetes and compared with those in diabetic rats with increased expression of methylglyoxal‐degrading enzyme glyoxalase‐I (Glo‐I) in cSMCs. Key Results After 7–8 weeks of T1D, endothelial cell‐mediated vasodilatation of cerebral arterioles was impaired. Microvascular leakage, gliosis, macrophage/neutrophil infiltration, NF‐κB activity and TNF‐α levels were increased, and density of perfused microvessels was reduced. Transient occlusion of a mid‐cerebral artery exacerbated ischaemia‐reperfusion injury. In cSMCs, Glo‐I protein was decreased, and the methylglyoxal‐synthesizing enzyme, vascular adhesion protein 1 (VAP‐1) and methylglyoxal were increased. Restoring Glo‐I protein in cSMCs of diabetic rats to control levels via gene transfer, blunted VAP‐1 and methylglyoxal increases, cECs dysfunction, microvascular leakage, inflammation, ischaemia‐reperfusion injury and increased microvessel perfusion. Conclusions and Implications Methylglyoxal generated by cSMCs induced cECs dysfunction, inflammation, hypoxia and exaggerated ischaemia‐reperfusion injury in diabetic rats. Lowering methylglyoxal produced by cSMCs may be a viable therapeutic strategy to preserve cECs function and blunt deleterious downstream consequences in T1D. PMID:27611446

Study on the Characteristics of Contrast-Enhanced Ultrasound and Its Utility in Assessing the Microvessel Density in Ovarian Tumors or Tumor-Like Lesions

PubMed Central

Wang, Junyan; Lv, Faqin; Fei, Xiang; Cui, Qiuli; Wang, Longxia; Gao, Xuewen; Yuan, Zhixian; Lin, Qian; Lv, Yali; Liu, Aijun

2011-01-01

Angiogenesis is a critical factor in tumor growth and metastasis, and microvessel density (MVD) was an important parameter for assessing vessels in tumors. However, radiologic assessment of tumor vascularity is not yet well established. In our study, we aimed at investigating the efficacy of contrast-enhanced ultrasonography (CEUS) in exploring the vascularity of the ovarian tumors or tumor-like lesions to assess the relationship between the parameters of the peak intensity (PI) and area under curve (AUC) on CEUS and MVD in ovarian masses. Compared to the contrast-enhanced ultrasound technique, conventional ultrasound shows limitation in differentiating benign and malignant ovarian tumors. The former is promising in improving the sensitivity of detecting small vessels and blood flow in ovarian tumors. Our results showed clear differences in enhancement patterns between benign and malignant ovary tumors or tumor-like lesions. The PI and AUC in the malignant tumors were significantly higher than those in the benign tumors or tumor-like lesions (p=0.001 and =0.01, respectively). The MVD was 43.1 ± 20.4 in the benign tumors or tumor-like lesions and was 65.3 ± 22.3 in the malignant ones (p= 0.01). In both the benign and malignant groups, the PI and AUC were correlated significantly with the MVD (r=0.595, p = 0.001; r =0.533, p = 0.003, respectively). The PI and AUC in CEUS can reflect the MVD in ovarin tumors. The PI and AUC of the ovarian masses in the contrast transvaginal sonography show significant correlation with the angiogenesis and may help in assessing tumor vascularity in ovarian masses. PMID:21614152

Prognostic significance of epithelial/stromal caveolin-1 expression in prostatic hyperplasia, high grade prostatic intraepithelial hyperplasia and prostatic carcinoma and its correlation with microvessel density.

PubMed

Mohammed, Dareen A; Helal, Duaa S

2017-03-01

Caveolin-1 may play a role in cancer development and progression. The aim was to record the expression and localization of caveolin-1 in benign prostatic hyperplasia (BPH), high grade prostatic intraepithelial neoplasia (HGPIN) and prostatic carcinoma (PCa). Microvessel density was evaluated with CD34 immunostain. Correlations with known prognostic factors of PCa were recorded. Immunohistochemical expression of caveolin-1 and the MVD was evaluated in 65 cases; BPH (25), HGPIN (20) and PCa (20). Stromal caveolin-1expression was significantly higher in BPH than HGPIN and PCca. There was significant inverse relation between stromal caveolin-1 expression and extension to lymph node and seminal vesicle in carcinoma cases. Epithelial caveolin-1 was significantly higher in carcinomas than in BPH and HGPIN. Epithelial expression in carcinoma was significantly associated with preoperative PSA, Gleason score and lymph node extension. MVD was significantly higher in PCa than in BPH and HGPIN. There were significant relations between MVD and preoperative PSA, Gleason score, lymph node and seminal vesicle extension. Stromal caveolin-1 was associated with low MVD while epithelial caveolin-1 with high MVD. Caveolin-1 plays an important role in prostatic carcinogenesis and metastasis. Stromal expression of caveolin-1 in PCa is lowered in relation to BPH and HGPIN. In PCa; stromal caveolin-1 was associated with good prognostic parameters. Epithelial caveolin-1 is significantly increased in PCa than BPH and HGPIN. It is associated with clinically aggressive disease. Caveolin-1 may play a role in angiogenesis. Copyright © 2017 National Cancer Institute, Cairo University. Production and hosting by Elsevier B.V. All rights reserved.

Novel MET/TIE2/VEGFR2 inhibitor altiratinib inhibits tumor growth and invasiveness in bevacizumab-resistant glioblastoma mouse models

PubMed Central

Piao, Yuji; Park, Soon Young; Henry, Verlene; Smith, Bryan D.; Tiao, Ningyi; Flynn, Daniel L.

2016-01-01

Background Glioblastoma highly expresses the proto-oncogene MET in the setting of resistance to bevacizumab. MET engagement by hepatocyte growth factor (HGF) results in receptor dimerization and autophosphorylation mediating tumor growth, invasion, and metastasis. Evasive revascularization and the recruitment of TIE2-expressing macrophages (TEMs) are also triggered by anti-VEGF therapy. Methods We investigated the activity of altiratinib (a novel balanced inhibitor of MET/TIE2/VEGFR2) against human glioblastoma stem cell lines in vitro and in vivo using xenograft mouse models. The biological activity of altiratinib was assessed in vitro by testing the expression of HGF-stimulated MET phosphorylation as well as cell viability after altiratinib treatment. Tumor volume, stem cell and mesenchymal marker levels, microvessel density, and TIE2-expressing monocyte infiltration were evaluated in vivo following treatment with a control, bevacizumab alone, bevacizumab combined with altiratinib, or altiratinib alone. Results In vitro, HGF-stimulated MET phosphorylation was completely suppressed by altiratinib in GSC17 and GSC267, and altiratinib markedly inhibited cell viability in several glioblastoma stem cell lines. More importantly, in multiple xenograft mouse models, altiratinib combined with bevacizumab dramatically reduced tumor volume, invasiveness, mesenchymal marker expression, microvessel density, and TIE2-expressing monocyte infiltration compared with bevacizumab alone. Furthermore, in the GSC17 xenograft model, altiratinib combined with bevacizumab significantly prolonged survival compared with bevacizumab alone. Conclusions Together, these data suggest that altiratinib may suppress tumor growth, invasiveness, angiogenesis, and myeloid cell infiltration in glioblastoma. Thus, altiratinib administered alone or in combination with bevacizumab may overcome resistance to bevacizumab and prolong survival in patients with glioblastoma. PMID:26965451

Microvessel Density Evaluation of the Effect of Enamel Matrix Derivative on Soft Tissue After Implant Placement: A Preliminary Study.

PubMed

Guimarães, George Furtado; de Araújo, Vera Cavalcanti; Nery, James Carlos; Peruzzo, Daiane Cristina; Soares, Andresa Borges

2015-01-01

Enamel matrix derivative (EMD) is commonly used in periodontal therapy and has been used successfully for periodontal regeneration. In addition, this material has a possible angiogenic effect that has been associated with enhanced wound healing. The aim of this study was to evaluate the effect of EMD on microvessel density (angiogenesis) on the soft tissues surrounding newly placed implants after 14 days. Five patients were selected, each requiring at least one implant on each side of the maxilla, in a split-mouth experimental design. The implants were placed in a two-stage procedure. Each side was then randomized as test or control. On the test side, 0.1 mL of EMD was topically applied to the soft tissues surrounding the implants, while the control side did not receive any treatment. Second-stage surgery was performed after 14 days. A 6-mm punch biopsy was performed for each implant, with the samples subsequently prepared for histology and immunohistochemistry. Quantitative vascularization analysis was performed, which involved counting three areas or "hotspots" containing vessels strongly positive for CD34 and CD105, a pan-endothelial and new vessel marker, respectively. There was no significant difference between test and control groups when evaluating the formation of new blood vessels. The total number of blood vessels, however, was significantly higher in the group treated with EMD (test group). Within the limits of the present study, it can be concluded that topical application of EMD on the soft tissues surrounding newly placed implants resulted in an increased number of blood vessels at 14 days, suggesting that EMD may play a beneficial role in this aspect of wound healing.

Thromboxane synthase expression and correlation with VEGF and angiogenesis in non-small cell lung cancer.

PubMed

Cathcart, Mary Clare; Gately, Kathy; Cummins, Robert; Drakeford, Clive; Kay, Elaine W; O'Byrne, Kenneth J; Pidgeon, Graham P

2014-05-01

Thromboxane synthase (TXS) metabolizes prostaglandin H2 into thromboxanes, which are biologically active on cancer cells. TXS over-expression has been reported in a range of cancers, and associated with angiogenesis and poor outcome. TXS has been identified as a potential therapeutic target in NSCLC. This study examines a link between TXS expression, angiogenesis, and survival in NSCLC. TXS and VEGF metabolite levels were measured in NSCLC serum samples (n=46) by EIA. TXB2 levels were correlated with VEGF. A 204-patient TMA was stained for TXS, VEGF, and CD-31 expression. Expression was correlated with a range of clinical parameters, including overall survival. TXS expression was correlated with VEGF and CD-31. Stable TXS clones were generated and the effect of overexpression on tumor growth and angiogenesis markers was examined in-vitro and in-vivo (xenograft mouse model). Serum TXB2 levels were correlated with VEGF (p<0.05). TXS and VEGF were expressed to a varying degree in NSCLC tissue. TXS was associated with VEGF (p<0.0001) and microvessel density (CD-31; p<0.05). TXS and VEGF expression levels were higher in adenocarcinoma (p<0.0001) and female patients (p<0.05). Stable overexpression of TXS increased VEGF secretion in-vitro. While no significant association with patient survival was observed for either TXS or VEGF in our patient cohort, TXS overexpression significantly (p<0.05) increased tumor growth in-vivo. TXS overexpression was also associated with higher levels of VEGF, microvessel density, and reduced apoptosis in xenograft tumors. TXS promotes tumor growth in-vivo in NSCLC, an effect which is at least partly mediated through increased tumor angiogenesis. Copyright © 2014 Elsevier B.V. All rights reserved.

EMMPRIN as a novel target for pancreatic cancer therapy

PubMed Central

Kim, Hyunki; Zhai, Guihua; Liu, Zhiyong; Samuel, Sharon; Shah, Nemil; Helman, Emily E.; Knowles, Joseph A.; Stockard, Cecil R.; Fineberg, Naomi S.; Grizzle, William E.; Zhou, Tong; Zinn, Kurt R.; Rosenthal, Eben L.

2013-01-01

The objective of this study was to evaluate extracelluar matrix metalloproteinase (EMMPRIN) as a novel target in orthotopic pancreatic-cancer murine models. MIA PaCa-2 human pancreatic tumor cells were implanted in groups 1 and 3-7, while MIA PaCa-2 EMMPRIN knockdown cells were implanted in group 2. Dosing with anti-EMMPRIN antibody started immediately after implantation for groups 1-3 (residual tumor model) and at 21 days after cell implantation for groups 4-7 (established tumor model). Groups 3, 5, and 7 were treated with anti-EMMRPIN antibody (0.2-1.0 mg) twice weekly for 2-3 weeks, while the other groups served as the control. In residual tumor model, tumor growth of anti-EMMPRIN treated group was successfully arrested for 21 days (15±4 mm3), significantly lower than that of EMMPRIN knockdown group (80±15 mm3; p=0.001) or control group (240±41 mm3; p<0.001). In established tumor model, anti-EMMPRIN therapy lowered tumor-volume increase about 40% compared with control regardless of dose amount. Ki67-expressed cell densities of group 5 was 939±150 mm−2, significantly lower than that of group 4 (1709±145 mm−2; p=0.006). Microvessel density of group 5 (30±6 mm−2) was also significantly lower than that of group 4 (53±5 mm−2; p=0.014), while the microvessel size of group 5 (191±22 μm2) was significantly larger than that of group 4 (113±26 μm2; p=0.049). These data show the high potential of anti-EMMPRIN therapy for pancreatic cancer, and support its clinical translation. PMID:21730821

Comparative analysis of COX-2, vascular endothelial growth factor and microvessel density in human renal cell carcinomas.

PubMed

Hemmerlein, B; Galuschka, L; Putzer, N; Zischkau, S; Heuser, M

2004-12-01

Cyclooxygenase-2 (COX-2) and vascular endothelial growth factor (VEGF) are frequently up-regulated in malignant tumours and play a role in proliferation, apoptosis, angiogenesis and tumour invasion. In the present study, the expression of COX-2 and VEGF in renal cell carcinoma (RCC) was analysed and correlated with the microvessel density (MVD). COX-2 and VEGF were analysed by realtime reverse transcriptase-polymerase chain reaction and immunohistochemistry. The MVD was assessed by CD31 immunohistochemistry. The expression of COX-2 and VEGF was determined in the RCC cell lines A498 and Caki-1 under short-term hypoxia and in multicellular tumour cell aggregates. COX-2 was expressed in RCC by tumour epithelia, endothelia and macrophages in areas of cystic tumour regression and tumour necrosis. COX-2 protein in RCC was not altered in comparison with normal renal tissue. VEGF mRNA was up-regulated in RCC and positively correlated with MVD. RCC with high up-regulation of VEGF mRNA showed weak intracytoplasmic expression of VEGF in tumour cells. Intracytoplasmic VEGF protein expression was negatively correlated with MVD. In RCC with necrosis the MVD was reduced in comparison with RCC without necrosis. A498 RCC cells down-regulated COX-2 and up-regulated VEGF under conditions of hypoxia. In Caki-1 cells COX-2 expression remained stable, whereas VEGF was significantly up-regulated. In multicellular A498 cell aggregates COX-2 and VEGF were up-regulated centrally, whereas no gradient was found in Caki-1 cells. COX-2 and VEGF are potential therapeutic targets because COX-2 and VEGF are expressed in RCC and associated cell populations such as endothelia and monocytes/macrophages.

Number of circulating endothelial progenitor cells and intratumoral microvessel density in non-small cell lung cancer patients: differences in angiogenic status between adenocarcinoma histologic subtypes.

PubMed

Maeda, Ryo; Ishii, Genichiro; Ito, Masami; Hishida, Tomoyuki; Yoshida, Junji; Nishimura, Mitsuyo; Haga, Hironori; Nagai, Kanji; Ochiai, Atsushi

2012-03-01

Angiogenesis plays a significant role in tumor progression. This study examined the association between the number of circulating endothelial progenitor cells (EPCs), intratumoral microvessel density (MVD) (both of which may be markers for neovascularization), and lung cancer histological types, particularly adenocarcinoma histological subtypes. A total of 83 stage I non-small cell lung cancer (NSCLC) patients underwent complete tumor resection between November 2009 and July 2010. The number of EPCs from the pulmonary artery of the resected lungs was measured by assaying CD34/vascular endothelial growth factor receptor 2 positive cells, and the MVD was assessed immunohistochemically in tumor specimens by staining for CD34. A statistically significant correlation between the number of EPCs from pulmonary artery and intratumoral MVD was found (p < 0.001). No statistically significant differences in the number of EPCs and the MVD were observed between the adenocarcinomas and the squamous cell carcinomas. Among the adenocarcinoma histological subtypes, a higher number of EPCs and MVD were found significantly more frequently in solid adenocarcinomas than in nonsolid adenocarcinomas (p < 0.001 and p = 0.011, respectively). In addition, solid adenocarcinomas showed higher levels of vascular endothelial growth factor using quantitative real-time polymerase chain reaction in the tumor tissue samples than in the nonsolid adenocarcinomas (p = 0.005). The higher number of circulating EPCs and the MVD of solid adenocarcinoma may indicate the presence of differences in the tumor angiogenic status between early-stage adenocarcinoma histological subtypes. Among adenocarcinoma patients, patients with solid adenocarcinoma may be the best candidates for antiangiogenic therapies.

Effects of radiotherapy and chemotherapy on angiogenesis and leukocyte infiltration in rectal cancer.

PubMed

Baeten, Coen I M; Castermans, Karolien; Lammering, Guido; Hillen, Femke; Wouters, Bradly G; Hillen, Harry F P; Griffioen, Arjan W; Baeten, Cornelius G M I

2006-11-15

We and others have shown that angiogenesis and leukocyte infiltration are important prognostic factors in rectal cancer. However, little is known about its possible changes in response to radiotherapy (RTX), which is frequently given to rectal tumors as a neoadjuvant treatment to improve the prognosis. We therefore investigated the biologic effects of RTX on these parameters using fresh-frozen biopsy samples of tumor and normal mucosa tissue before and after RTX. Biopsy samples were taken from a total of 34 patients before and after either a short course or long course of RTX combined with chemotherapy. The following parameters were analyzed by immunohistochemistry, flow cytometry, or quantitative real-time polymerase chain reaction: Microvessel density, leukocyte infiltration, proliferating epithelial and tumor cells, proliferating endothelial cells, adhesion molecule expression on endothelial cells, and the angiogenic mRNA profile. The tumor biopsy samples taken after RTX treatment demonstrated a significant decrease in microvessel density and the number of proliferating tumor cells and proliferating endothelial cells (p < 0.001). In contrast, the leukocyte infiltration, the levels of basic fibroblast growth factor in carcinoma tissue, and the adhesion molecule expression on endothelial cells in normal as well as carcinoma tissue increased significantly (p < 0.05). Our data show that together with an overall decrease in tumor cell and endothelial cell proliferation, RTX results in an increase in the expression of adhesion molecules that stimulate leukocyte infiltration. This suggests the possibility that, in addition to its direct cytotoxic effect, radiation may also stimulate an immunologic tumor response that could contribute to the documented improvement in local tumor control and distal failure rate of rectal cancers.

Microvessel density in head and neck squamous cell carcinoma.

PubMed

Szafarowski, Tomasz; Sierdzinski, Janusz; Szczepanski, Miroslaw J; Whiteside, Theresa L; Ludwig, Nils; Krzeski, Antoni

2018-05-10

Microvessel density (MVD) corresponds to the intensity of neo-angiogenesis. MVD assessments are based on the expression levels of the vascular endothelium markers such as, e.g., CD34 or CD105. The goal of this study was to assess MVD among patients with head and neck squamous cell carcinoma (HNSCC), and to evaluate the predictive value of MVD in head and neck cancers. The study included 49 patients treated for HNSCC and 11 patients with dysplasia of the upper respiratory tract epithelium. Control tissues consisted of 12 normal mucous membranes of the throat. Expression levels of MVD markers were assessed by immunohistochemistry (IHC) using tissue microarrays (TMA). Clinicopathological factors and patients' survival over the 5-year follow-up period were analyzed. The MVD/CD34 values were found to be significantly elevated in the HNSCCs compared to the non-malignant control tissues (p = 0.001) and to dysplastic tissues. (p = 0.02). Significantly higher MVD/CD105 values were also seen in the tumor compared to the control tissues (p = 0.001) or the dysplastic tissues (p = 0.001). Unexpectedly, significantly lower MVD/CD34 values were seen in the tumor tissues of patients with the T3-T4 tumors compared to those with T1-T2 tumors (p = 0.01). HNSCCs have statistically higher MVD values compared to dysplasia of the upper respiratory tract epithelium. However, the MVD/CD34 values did not correlate with local invasiveness (the T feature) of HNSCCs. This counterintuitive observation suggests that assessments of MVD as performed on TMA by IHC using anti-CD34 or anti-CD105 antibodies considered to be specific for endothelial cell markers might underestimate the extent of the tumor vascularity in HNSCC.

Anti-tumor activity of high-dose EGFR tyrosine kinase inhibitor and sequential docetaxel in wild type EGFR non-small cell lung cancer cell nude mouse xenografts

PubMed Central

Tang, Ning; Zhang, Qianqian; Fang, Shu; Han, Xiao; Wang, Zhehai

2017-01-01

Treatment of non-small-cell lung cancer (NSCLC) with wild-type epidermal growth factor receptor (EGFR) is still a challenge. This study explored antitumor activity of high-dose icotinib (an EGFR tyrosine kinase inhibitor) plus sequential docetaxel against wild-type EGFR NSCLC cells-generated nude mouse xenografts. Nude mice were subcutaneously injected with wild-type EGFR NSCLC A549 cells and divided into different groups for 3-week treatment. Tumor xenograft volumes were monitored and recorded, and at the end of experiments, tumor xenografts were removed for Western blot and immunohistochemical analyses. Compared to control groups (negative control, regular-dose icotinib [IcoR], high-dose icotinib [IcoH], and docetaxel [DTX]) and regular icotinib dose (60 mg/kg) with docetaxel, treatment of mice with a high-dose (1200 mg/kg) of icotinib plus sequential docetaxel for 3 weeks (IcoH-DTX) had an additive effect on suppression of tumor xenograft size and volume (P < 0.05). Icotinib-containing treatments markedly reduced phosphorylation of EGFR, mitogen activated protein kinase (MAPK), and protein kinase B (Akt), but only the high-dose icotinib-containing treatments showed an additive effect on CD34 inhibition (P < 0.05), an indication of reduced microvessel density in tumor xenografts. Moreover, high-dose icotinib plus docetaxel had a similar effect on mouse weight loss (a common way to measure adverse reactions in mice), compared to the other treatment combinations. The study indicate that the high dose of icotinib plus sequential docetaxel (IcoH-DTX) have an additive effect on suppressing the growth of wild-type EGFR NSCLC cell nude mouse xenografts, possibly through microvessel density reduction. Future clinical trials are needed to confirm the findings of this study. PMID:27852073

Efficacy of Sunitinib and Radiotherapy in Genetically Engineered Mouse Model of Soft-Tissue Sarcoma

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoon, Sam S.; Stangenberg, Lars; Lee, Yoon-Jin

Purpose: Sunitinib (SU) is a multitargeted receptor tyrosine kinase inhibitor of the vascular endothelial growth factor and platelet-derived growth factor receptors. The present study examined SU and radiotherapy (RT) in a genetically engineered mouse model of soft tissue sarcoma (STS). Methods and Materials: Primary extremity STSs were generated in genetically engineered mice. The mice were randomized to treatment with SU, RT (10 Gy x 2), or both (SU+RT). Changes in the tumor vasculature before and after treatment were assessed in vivo using fluorescence-mediated tomography. The control and treated tumors were harvested and extensively analyzed. Results: The mean fluorescence in themore » tumors was not decreased by RT but decreased 38-44% in tumors treated with SU or SU+RT. The control tumors grew to a mean of 1378 mm{sup 3} after 12 days. SU alone or RT alone delayed tumor growth by 56% and 41%, respectively, but maximal growth inhibition (71%) was observed with the combination therapy. SU target effects were confirmed by loss of target receptor phosphorylation and alterations in SU-related gene expression. Cancer cell proliferation was decreased and apoptosis increased in the SU and RT groups, with a synergistic effect on apoptosis observed in the SU+RT group. RT had a minimal effect on the tumor microvessel density and endothelial cell-specific apoptosis, but SU alone or SU+RT decreased the microvessel density by >66% and induced significant endothelial cell apoptosis. Conclusion: SU inhibited STS growth by effects on both cancer cells and tumor vasculature. SU also augmented the efficacy of RT, suggesting that this combination strategy could improve local control of STS.« less

Dendritic Cell Transmigration through Brain Microvessel Endothelium Is Regulated by MIP-1α Chemokine and Matrix Metalloproteinases1

PubMed Central

Zozulya, Alla L.; Reinke, Emily; Baiu, Dana C.; Karman, Jozsef; Sandor, Matyas; Fabry, Zsuzsanna

2007-01-01

Dendritic cells (DCs) accumulate in the CNS during inflammatory diseases, but the exact mechanism regulating their traffic into the CNS remains to be defined. We now report that MIP-1α increases the transmigration of bone marrow-derived, GFP-labeled DCs across brain microvessel endothelial cell monolayers. Furthermore, occludin, an important element of endothelial tight junctions, is reorganized when DCs migrate across brain capillary endothelial cell monolayers without causing significant changes in the barrier integrity as measured by transendothelial electrical resistance. We show that DCs produce matrix metalloproteinases (MMP) -2 and -9 and GM6001, an MMP inhibitor, decreases both baseline and MIP-1α -induced DC transmigration. These observations suggest that DC transmigration across brain endothelial cell monolayers is partly MMP dependent. The migrated DCs express higher levels of CD40, CD80, and CD86 costimulatory molecules and induce T cell proliferation, indicating that the transmigration of DCs across brain endothelial cell monolayers contributes to the maintenance of DC Ag-presenting function. The MMP dependence of DC migration across brain endothelial cell monolayers raises the possibility that MMP blockers may decrease the initiation of T cell recruitment and neuroinflammation in the CNS. PMID:17182592

Brain vascular image enhancement based on gradient adjust with split Bregman

NASA Astrophysics Data System (ADS)

Liang, Xiao; Dong, Di; Hui, Hui; Zhang, Liwen; Fang, Mengjie; Tian, Jie

2016-04-01

Light Sheet Microscopy is a high-resolution fluorescence microscopic technique which enables to observe the mouse brain vascular network clearly with immunostaining. However, micro-vessels are stained with few fluorescence antibodies and their signals are much weaker than large vessels, which make micro-vessels unclear in LSM images. In this work, we developed a vascular image enhancement method to enhance micro-vessel details which should be useful for vessel statistics analysis. Since gradient describes the edge information of the vessel, the main idea of our method is to increase the gradient values of the enhanced image to improve the micro-vessels contrast. Our method contained two steps: 1) calculate the gradient image of LSM image, and then amplify high gradient values of the original image to enhance the vessel edge and suppress low gradient values to remove noises. Then we formulated a new L1-norm regularization optimization problem to find an image with the expected gradient while keeping the main structure information of the original image. 2) The split Bregman iteration method was used to deal with the L1-norm regularization problem and generate the final enhanced image. The main advantage of the split Bregman method is that it has both fast convergence and low memory cost. In order to verify the effectiveness of our method, we applied our method to a series of mouse brain vascular images acquired from a commercial LSM system in our lab. The experimental results showed that our method could greatly enhance micro-vessel edges which were unclear in the original images.

The fabrication of PLGA microvessel scaffolds with nano-patterned inner walls.

PubMed

Wang, Gou-Jen; Lin, Yan-Cheng; Hsu, Shan-Hui

2010-10-01

Poly (lactic-co-glycolic acid) (PLGA) is one of the most commonly used biodegradable, biocompatible materials. Nanostructured PLGA has immense potential for application in tissue engineering. In this article we discuss a novel approach for the fabrication of PLGA microvessel scaffolds with nanostructured inner walls. In this novel nano-patterning approach, the thermal reflow technique is first adapted to fabricate a semi-cylindrical photoresist master mold. A thin film of titanium and a thin film of aluminum are sputtered in sequence on the semi-cylindrical microvessel network. Aluminum foil anodization is then executed to transform the aluminum thin film into a porous anodic aluminum oxide (AAO) film. During the casting process a PLGA solution is cast on the AAO film to build up semi-cylindrical PLGA microstructures with nanostructured inner walls after which inductive coupled plasma (ICP) is implemented to assist bonding of the two PLGA structures. The result is the building of a network of microchannels with nano-patterned inner walls. Bovine endothelial cells (BECs) are carefully cultured in the scaffold via semi-dynamic seeding for 7 days. Observations show that the BECs grew more separately in a nano-patterned microvessel scaffold than they did in a smooth surface scaffold.

Is There a Direct Correlation Between Microvascular Wall Structure and k-Trans Values Obtained From Perfusion CT Measurements in Lymphomas?

PubMed

Horger, Marius; Fallier-Becker, Petra; Thaiss, Wolfgang M; Sauter, Alexander; Bösmüller, Hans; Martella, Manuela; Preibsch, Heike; Fritz, Jan; Nikolaou, Konstantin; Kloth, Christopher

2018-05-03

This study aimed to test the hypothesis that ultrastructural wall abnormalities of lymphoma vessels correlate with perfusion computed tomography (PCT) kinetics. Our local institutional review board approved this prospective study. Between February 2013 and June 2016, we included 23 consecutive subjects with newly diagnosed lymphoma, who were referred for computed tomography-guided biopsy (6 women, 17 men; mean age, 60.61 ± 12.43 years; range, 28-74 years) and additionally agreed to undergo PCT of the target lymphoma tissues. PCT was obtained for 40 seconds using 80 kV, 120 mAs, 64 × 0.6-mm collimation, 6.9-cm z-axis coverage, and 26 volume measurements. Mean and maximum k-trans (mL/100 mL/min), blood flow (BF; mL/100 mL/min) and blood volume (BV) were quantified using the deconvolution and the maximum slope + Patlak calculation models. Immunohistochemical staining was performed for microvessel density quantification (vessels/m 2 ), and electron microscopy was used to determine the presence or absence of tight junctions, endothelial fenestration, basement membrane, and pericytes, and to measure extracellular matrix thickness. Extracellular matrix thickness as well as the presence or absence of tight junctions, basal lamina, and pericytes did not correlate with computed tomography perfusion parameters. Endothelial fenestrations correlated significantly with mean BF deconvolution (P = .047, r = 0.418) and additionally was significantly associated with higher mean BV deconvolution (P < .005). Mean k-trans Patlak correlated strongly with mean k-trans deconvolution (r = 0.939, P = .001), and both correlated with mean BF deconvolution (P = .001, r = 0.748), max BF deconvolution (P = .028, r = 0.564), mean BV deconvolution (P = .001, r = 0.752), and max BV deconvolution (P = .001, r = 0.771). Microvessel density correlated with max k-trans deconvolution (r = 0.564, P = .023). Vascular endothelial growth factor receptor-3 expression (receptor specific for lymphatics) correlated significantly with max k-trans Patlak (P = .041, r = 0.686) and mean BF deconvolution (P = .038, r = 0.695). k-Trans values of PCT do not correlate with ultrastructural microvessel features, whereas endothelial fenestrations correlate with increased intra-tumoral BVs. Copyright © 2018 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.

LASER BIOLOGY AND MEDICINE: Recording of lymph flow dynamics in microvessels using correlation properties of scattered coherent radiation

NASA Astrophysics Data System (ADS)

Fedosov, I. V.; Tuchin, Valerii V.; Galanzha, E. I.; Solov'eva, A. V.; Stepanova, T. V.

2002-11-01

The direction-sensitive method of microflow velocity measurements based on the space — time correlation properties of the dynamic speckle field is described and used for in vivo monitoring of lymph flow in the vessels of rat mesentery. The results of measurements are compared with the data obtained from functional video microscopy of the microvessel region.

The inhibitor of 20-HETE synthesis, TS-011, improves cerebral microcirculatory autoregulation impaired by middle cerebral artery occlusion in mice.

PubMed

Marumo, Toshiyuki; Eto, Kei; Wake, Hiroaki; Omura, Tomohiro; Nabekura, Junichi

2010-11-01

20-Hydroxyeicosatetraenoic acid is a potent vasoconstrictor that contributes to cerebral ischaemia. An inhibitor of 20-Hydroxyeicosatetraenoic acid synthesis, TS-011, reduces infarct volume and improves neurological deficits in animal stroke models. However, little is known about how TS-011 affects the microvessels in ischaemic brain. Here, we investigated the effect of TS-011 on microvessels after cerebral ischaemia. TS-011 (0.3 mg·kg(-1) ) or a vehicle was infused intravenously for 1 h every 6 h in a mouse model of stroke, induced by transient occlusion of the middle cerebral artery occlusion following photothrombosis. The cerebral blood flow velocity and the vascular perfusion area of the peri-infarct microvessels were measured using in vivo two-photon imaging. The cerebral blood flow velocities in the peri-infarct microvessels decreased at 1 and 7 h after reperfusion, followed by an increase at 24 h after reperfusion in the vehicle-treated mice. We found that TS-011 significantly inhibited both the decrease and the increase in the blood flow velocities in the peri-infarct microvessels seen in the vehicle-treated mice after reperfusion. In addition, TS-011 significantly inhibited the reduction in the microvascular perfusion area after reperfusion, compared with the vehicle-treated group. Moreover, TS-011 significantly reduced the infarct volume by 40% at 72 h after middle cerebral artery occlusion. These findings demonstrated that infusion of TS-011 improved defects in the autoregulation of peri-infarct microcirculation and reduced the infarct volume. Our results could be relevant to the treatment of cerebral ischaemia. © 2010 The Authors. British Journal of Pharmacology © 2010 The British Pharmacological Society.

A Simple and Reproducible Method to Prepare Membrane Samples from Freshly Isolated Rat Brain Microvessels.

PubMed

Brzica, Hrvoje; Abdullahi, Wazir; Reilly, Bianca G; Ronaldson, Patrick T

2018-05-07

The blood-brain barrier (BBB) is a dynamic barrier tissue that responds to various pathophysiological and pharmacological stimuli. Such changes resulting from these stimuli can greatly modulate drug delivery to the brain and, by extension, cause considerable challenges in the treatment of central nervous system (CNS) diseases. Many BBB changes that affect pharmacotherapy, involve proteins that are localized and expressed at the level of endothelial cells. Indeed, such knowledge on BBB physiology in health and disease has sparked considerable interest in the study of these membrane proteins. From a basic science research standpoint, this implies a requirement for a simple but robust and reproducible method for isolation of microvessels from brain tissue harvested from experimental animals. In order to prepare membrane samples from freshly isolated microvessels, it is essential that sample preparations be enriched in endothelial cells but limited in the presence of other cell types of the neurovascular unit (i.e., astrocytes, microglia, neurons, pericytes). An added benefit is the ability to prepare samples from individual animals in order to capture the true variability of protein expression in an experimental population. In this manuscript, details regarding a method that is utilized for isolation of rat brain microvessels and preparation of membrane samples are provided. Microvessel enrichment, from samples derived, is achieved by using four centrifugation steps where dextran is included in the sample buffer. This protocol can easily be adapted by other laboratories for their own specific applications. Samples generated from this protocol have been shown to yield robust experimental data from protein analysis experiments that can greatly aid the understanding of BBB responses to physiological, pathophysiological, and pharmacological stimuli.

Cardioprotective effects of red wine and vodka in a model of endothelial dysfunction

PubMed Central

Lassaletta, Antonio D; Chu, Louis M; Elmadhun, Nassrene Y; Burgess, Thomas A; Feng, Jun; Robich, Michael P; Sellke, Frank W

2012-01-01

Background Moderate alcohol consumption is largely believed to be cardioprotective, while red wine is hypothesized to offer benefit in part due to the pro-angiogenic and antioxidant properties of polyphenols. We investigated the cardiovascular effects of both red wine and vodka in a swine model of endothelial dysfunction. Methods Twenty-seven male Yorkshire swine fed a high-fat/cholesterol diet were divided into three groups and received either no alcohol (Control), red wine, or vodka. After seven weeks, myocardial perfusion was measured, and ventricular tissue was analyzed for microvascular reactivity, and immunohistochemical studies. Results There were no differences in myocardial perfusion, in arteriolar or capillary density, or in VEGF expression among groups. Total protein oxidation as well as expression of superoxide dismutase-1 and -2 (SOD1, SOD2) and NADPH-oxidase (NOX2) was decreased in both treatment groups compared to controls. Endothelium-dependent microvessel relaxation, however, was significantly improved only in the red wine-supplemented group. Conclusions Supplementation with both red wine and vodka decreased oxidative stress by several measures, implicating the effects of ethanol in reducing oxidative stress in the myocardium. However, it was only in the red wine-supplemented group that an improvement in microvessel function was observed. This suggests that a component of red wine, independent of ethanol, possibly a polyphenol such as resveratrol, may confer cardioprotection by normalizing endothelial dysfunction induced by an atherogenic diet. PMID:22748601

Prognostic significance of anaplasia and angiogenesis in childhood medulloblastoma: a pediatric oncology group study.

PubMed

Ozer, Erdener; Sarialioglu, Faik; Cetingoz, Riza; Yüceer, Nurullah; Cakmakci, Handan; Ozkal, Sermin; Olgun, Nur; Uysal, Kamer; Corapcioglu, Funda; Canda, Serefettin

2004-01-01

The purpose of this study was to investigate whether quantitative assessment of cytologic anaplasia and angiogenesis may predict the clinical prognosis in medulloblastoma and stratify the patients to avoid both undertreatment and overtreatment. Medulloblastomas from 23 patients belonging to the Pediatric Oncology Group were evaluated with respect to some prognostic variables, including histologic assessment of nodularity and desmoplasia, grading of anaplasia, measurement of nuclear size, mitotic cell count, quantification of angiogenesis, including vascular surface density (VSD) and microvessel number (NVES), and immunohistochemical scoring of vascular endothelial growth factor (VEGF) expression. Univariate and multivariate analyses for prognostic indicators for survival were performed. Univariate analysis revealed that extensive nodularity was a significant favorable prognostic factor, whereas the presence of anaplasia, increased nuclear size, mitotic rate, VSD, and NVES were significant unfavorable prognostic factors. Using multivariate analysis, increased nuclear size was found to be an independent unfavorable prognostic factor for survival. Neither the presence of desmoplasia nor VEGF expression was significantly related to patient survival. Although care must be taken not to overstate the importance of the results of this single-institution preliminary report, pathologic grading of medulloblastomas with respect to grading of anaplasia and quantification of nodularity, nuclear size, and microvessel profiles may be clinically useful for the treatment of medulloblastomas. Further validation of the independent prognostic significance of nuclear size in stratifying patients is required.

Tc17 Cells in Patients with Uterine Cervical Cancer

PubMed Central

Zhang, Yan; Hou, Fei; Liu, Xin; Ma, Daoxin; Zhang, Youzhong; Kong, Beihua; Cui, Baoxia

2014-01-01

Background The existence of Tc17 cells was recently shown in several types of infectious and autoimmune diseases, but their distribution and functions in uterine cervical cancer (UCC) have not been fully elucidated. Methods The frequency of Tc17 cells in peripheral blood samples obtained from UCC patients, cervical intraepithelial neoplasia (CIN) patients and healthy controls was determined by flow cytometry. Besides, the prevalence of Tc17 cells and their relationships to Th17 cells and Foxp3-expressing T cells as well as microvessels in tissue samples of the patients were assessed by immunohistochemistry staining. Results Compared to controls, patients with UCC or CIN had a higher proportion of Tc17 cells in both peripheral blood and cervical tissues, but the level of Tc17 cells in UCC tissues was significantly higher than that in CIN tissues. Besides, the increased level of Tc17 in UCC patients was associated with the status of pelvic lymph node metastases and increased microvessel density. Finally, significant correlations of infiltration between Tc17 cells and Th17 cells or Foxp3-expressing T cells were observed in UCC and CIN tissues. Conclusions This study indicates that Tc17 cell infiltration in cervical cancers is associated with cancer progression accompanied by increased infiltrations of Th17 cells and regulatory T cells as well as promoted tumor vasculogenesis. PMID:24523865

In vivo endoscopic Doppler optical coherence tomography imaging of mouse colon

NASA Astrophysics Data System (ADS)

Welge, Weston A.; Barton, Jennifer K.

2016-03-01

Colorectal cancer remains the second deadliest cancer in the United States, despite the high sensitivity and specificity of colonoscopy and sigmoidoscopy. While these standard imaging procedures can accurately detect medium and large polyps, some studies have shown miss rates up to 25% for polyps less than 5 mm in diameter. An imaging modality capable of detecting small lesions could potentially improve patient outcomes. Optical coherence tomography (OCT) has been shown to be a powerful imaging modality for adenoma detection in a mouse model of colorectal cancer. While previous work has focused on analyzing the structural OCT images based on thickening of the mucosa and changes in light attenuation in depth, imaging the microvasculature of the colon may enable earlier detection of polyps. The structure and function of vessels grown to support tumor growth are markedly different from healthy vessels. Doppler OCT is capable of imaging microvessels in vivo. We developed a method of processing raw fringe data from a commercial swept-source OCT system using a lab-built miniature endoscope to extract microvessels. This method can be used to measure vessel count and density and to measure flow velocities. This may improve early detection and aid in the development of new chemopreventive and chemotherapeutic drugs. We present, to the best of our knowledge, the first endoscopic Doppler OCT images of in vivo mouse colon.

Intravital lectin perfusion analysis of vascular permeability in human micro- and macro- blood vessels.

PubMed

Debbage, P L; Sölder, E; Seidl, S; Hutzler, P; Hugl, B; Ofner, D; Kreczy, A

2001-10-01

We previously applied intravital lectin perfusion in mouse models to elucidate mechanisms underlying vascular permeability. The present work transfers this technique to human models, analysing vascular permeability in macro- and microvessels. Human vascular endothelial surface carbohydrate biochemistry differs significantly from its murine counterpart, lacking alpha-galactosyl epitopes and expressing the L-fucose moiety in the glycocalyx; the poly-N-lactosamine glycan backbone is common to all mammals. We examined extensively lectin binding specificities in sections and in vivo, and then applied the poly-N-lactosamine-specific lectin LEA and the L-fucose-specific lectin UEA-I in human intravital perfusions. Transendothelial transport differed in macrovessels and microvessels. In microvessels of adult human fat tissue, rectal wall and rectal carcinomas, slow transendothelial transport by vesicles was followed by significant retention at the subendothelial basement membrane; paracellular passage was not observed. Passage time exceeded 1 h. Thus we found barrier mechanisms resembling those we described previously in murine tissues. In both adult and fetal macrovessels, the vena saphena magna and the umbilical vein, respectively, rapid passage across the endothelial lining was observed, the tracer localising completely in the subendothelial tissues within 15 min; vesicular transport was more rapid than in microvessels, and retention at the subendothelial basement membrane briefer.

Sox10+ adult stem cells contribute to biomaterial encapsulation and microvascularization

PubMed Central

Wang, Dong; Wang, Aijun; Wu, Fan; Qiu, Xuefeng; Li, Ye; Chu, Julia; Huang, Wen-Chin; Xu, Kang; Gong, Xiaohua; Li, Song

2017-01-01

Implanted biomaterials and biomedical devices generally induce foreign body reaction and end up with encapsulation by a dense avascular fibrous layer enriched in extracellular matrix. Fibroblasts/myofibroblasts are thought to be the major cell type involved in encapsulation, but it is unclear whether and how stem cells contribute to this process. Here we show, for the first time, that Sox10+ adult stem cells contribute to both encapsulation and microvessel formation. Sox10+ adult stem cells were found sparsely in the stroma of subcutaneous loose connective tissues. Upon subcutaneous biomaterial implantation, Sox10+ stem cells were activated and recruited to the biomaterial scaffold, and differentiated into fibroblasts and then myofibroblasts. This differentiation process from Sox10+ stem cells to myofibroblasts could be recapitulated in vitro. On the other hand, Sox10+ stem cells could differentiate into perivascular cells to stabilize newly formed microvessels. Sox10+ stem cells and endothelial cells in three-dimensional co-culture self-assembled into microvessels, and platelet-derived growth factor had chemotactic effect on Sox10+ stem cells. Transplanted Sox10+ stem cells differentiated into smooth muscle cells to stabilize functional microvessels. These findings demonstrate the critical role of adult stem cells in tissue remodeling and unravel the complexity of stem cell fate determination. PMID:28071739

Retooling Laser Speckle Contrast Analysis Algorithm to Enhance Non-Invasive High Resolution Laser Speckle Functional Imaging of Cutaneous Microcirculation

NASA Astrophysics Data System (ADS)

Gnyawali, Surya C.; Blum, Kevin; Pal, Durba; Ghatak, Subhadip; Khanna, Savita; Roy, Sashwati; Sen, Chandan K.

2017-01-01

Cutaneous microvasculopathy complicates wound healing. Functional assessment of gated individual dermal microvessels is therefore of outstanding interest. Functional performance of laser speckle contrast imaging (LSCI) systems is compromised by motion artefacts. To address such weakness, post-processing of stacked images is reported. We report the first post-processing of binary raw data from a high-resolution LSCI camera. Sharp images of low-flowing microvessels were enabled by introducing inverse variance in conjunction with speckle contrast in Matlab-based program code. Extended moving window averaging enhanced signal-to-noise ratio. Functional quantitative study of blood flow kinetics was performed on single gated microvessels using a free hand tool. Based on detection of flow in low-flow microvessels, a new sharp contrast image was derived. Thus, this work presents the first distinct image with quantitative microperfusion data from gated human foot microvasculature. This versatile platform is applicable to study a wide range of tissue systems including fine vascular network in murine brain without craniotomy as well as that in the murine dorsal skin. Importantly, the algorithm reported herein is hardware agnostic and is capable of post-processing binary raw data from any camera source to improve the sensitivity of functional flow data above and beyond standard limits of the optical system.

Retooling Laser Speckle Contrast Analysis Algorithm to Enhance Non-Invasive High Resolution Laser Speckle Functional Imaging of Cutaneous Microcirculation

PubMed Central

Gnyawali, Surya C.; Blum, Kevin; Pal, Durba; Ghatak, Subhadip; Khanna, Savita; Roy, Sashwati; Sen, Chandan K.

2017-01-01

Cutaneous microvasculopathy complicates wound healing. Functional assessment of gated individual dermal microvessels is therefore of outstanding interest. Functional performance of laser speckle contrast imaging (LSCI) systems is compromised by motion artefacts. To address such weakness, post-processing of stacked images is reported. We report the first post-processing of binary raw data from a high-resolution LSCI camera. Sharp images of low-flowing microvessels were enabled by introducing inverse variance in conjunction with speckle contrast in Matlab-based program code. Extended moving window averaging enhanced signal-to-noise ratio. Functional quantitative study of blood flow kinetics was performed on single gated microvessels using a free hand tool. Based on detection of flow in low-flow microvessels, a new sharp contrast image was derived. Thus, this work presents the first distinct image with quantitative microperfusion data from gated human foot microvasculature. This versatile platform is applicable to study a wide range of tissue systems including fine vascular network in murine brain without craniotomy as well as that in the murine dorsal skin. Importantly, the algorithm reported herein is hardware agnostic and is capable of post-processing binary raw data from any camera source to improve the sensitivity of functional flow data above and beyond standard limits of the optical system. PMID:28106129

Plasma membrane localization of multidrug resistance-associated protein homologs in brain capillary endothelial cells.

PubMed

Zhang, Yan; Schuetz, John D; Elmquist, William F; Miller, Donald W

2004-11-01

Several multidrug resistance-associated protein (MRP) homologs are expressed in brain microvessel endothelial cells forming the blood-brain barrier (BBB). The influence of these MRP transporters on BBB permeability will be dependent on their localization within the brain microvessel endothelial cells. Using two different and complementary approaches, the localization of various MPR homologs (MRP1, MRP4, and MRP5) was examined in primary cultured bovine brain microvessel endothelial cells (BBMECs). The first approach involved centrifugal separation of apical and basolateral plasma membranes of cultured BBMECs. The membrane fractions were then subjected to Western blot analysis for MRPs. The second approach used confocal laser scanning microscopy to determine membrane localization of MRPs in BBMECs. Results show a predominantly apical plasma membrane distribution for MRP1 and MRP5, and an almost equal distribution of MRP4 on the apical and basolateral plasma membrane of BBMECs. These studies provide the first demonstration of the localization of MRP1, MRP4, and MRP5 homologs in brain microvessel endothelial cells. The present studies also indicate that the localization of MRPs in the endothelial cells forming the BBB is different from that observed in polarized epithelial cells and thus may contribute to the reduced entry and enhanced elimination of organic anions and nucleotides in the brain.

Characterization of atrial natriuretic peptide receptors in brain microvessel endothelial cells

NASA Technical Reports Server (NTRS)

Whitson, P. A.; Huls, M. H.; Sams, C. F.

1991-01-01

Atrial natriuretic peptide (ANP) binding and ANP-induced increases in cyclic guanosine monophosphate (cGMP) levels have been observed in brain microvessels (Chabrier et al., 1987; Steardo and Nathanson, 1987), suggesting that this fluid-regulating hormone may play a role in the fluid homeostasis of the brain. This study was initiated to characterize the ANP receptors in primary cultures of brain microvessel endothelial cells (BMECs). The apparent equilibrium dissociation constant, Kd, for ANP increased from 0.25 nM to 2.5 nM, and the number of ANP binding sites as determined by Scatchard analysis increased from 7,100 to 170,000 sites/cell between 2 and 10 days of culture following monolayer formation. Time- and concentration-dependent studies on the stimulation of cGMP levels by ANP indicated that guanylate cyclase-linked ANP receptors were present in BMECs. The relative abilities of ANP, brain natriuretic peptide (BNP), and a truncated analog of ANP containing amino acids 5-27 (ANP 5-27) to modulate the accumulation of cGMP was found to be ANP greater than BNP much greater than ANP 5-27. Affinity cross-linking with disuccinimidyl suberate and radiolabeled ANP followed by gel electrophoresis under reducing conditions demonstrated a single band corresponding to the 60-70 kD receptor, indicating the presence of the nonguanylate cyclase-linked ANP receptor. Radiolabeled ANP binding was examined in the presence of various concentrations of either ANP, BNP, or ANP 5-27 and suggested that a large proportion of the ANP receptors present in blood-brain barrier endothelial cells bind all of these ligands similarly. These data indicate both guanylate cyclase linked and nonguanylate cyclase linked receptors are present on BMECs and that a higher proportion of the nonguanylate cyclase linked receptors is expressed. This in vitro culture system may provide a valuable tool for the examination of ANP receptor expression and function in blood-brain barrier endothelial cells.

Targeted disruption of deep-lying neocortical microvessels in rat using ultrashort laser pulses

NASA Astrophysics Data System (ADS)

Nishimura, Nozomi; Schaffer, Christopher B.; Friedman, Beth; Tsai, Philbert S.; Lyden, Patrick D.; Kleinfeld, David

2004-06-01

The study of neurovascular diseases such as vascular dementia and stroke require novel models of targeted vascular disruption in the brain. We describe a model of microvascular disruption in rat neocortex that uses ultrashort laser pulses to induce localized injury to specific targeted microvessels and uses two-photon microscopy to monitor and guide the photodisruption process. In our method, a train of high-intensity, 100-fs laser pulses is tightly focused into the lumen of a blood vessel within the upper 500 μm of cortex. Photodisruption induced by these laser pulses creates injury to a single vessel located at the focus of the laser, leaving the surrounding tissue intact. This photodisruption results in three modalities of localized vascular injury. At low power, blood plasma extravasation can be induced. The vessel itself remains intact, while serum is extravasated into the intercellular space. Localized ischemia caused by an intravascular clot results when the photodisruption leads to a brief disturbance of the vascular walls that initiates an endogenous clotting cascade. The formation of a localized thrombus stops the blood flow at the location of the photodisruption. A hemorrhage, defined as a large extravasation of blood including plasma and red blood cells, results when higher laser power is used. The targeted vessel does not remain intact.

Modifications of the mouse bone marrow microenvironment favor angiogenesis and correlate with disease progression from asymptomatic to symptomatic multiple myeloma

PubMed Central

Calcinotto, Arianna; Ponzoni, Maurilio; Ria, Roberto; Grioni, Matteo; Cattaneo, Elena; Villa, Isabella; Sabrina Bertilaccio, Maria Teresa; Chesi, Marta; Rubinacci, Alessandro; Tonon, Giovanni; Bergsagel, P Leif; Vacca, Angelo; Bellone, Matteo

2015-01-01

While multiple myeloma (MM) is almost invariably preceded by asymptomatic monoclonal gammopathy of undetermined significance (MGUS) and/or smoldering MM (SMM), the alterations of the bone marrow (BM) microenvironment that establish progression to symptomatic disease are circumstantial. Here we show that in Vk*MYC mice harboring oncogene-driven plasma cell proliferative disorder, disease appearance associated with substantial modifications of the BM microenvironment, including a progressive accumulation of both CD8+ and CD4+ T cells with a dominant T helper type 1 (Th1) response. Progression from asymptomatic to symptomatic MM was characterized by further BM accrual of T cells with reduced Th1 and persistently increased Th2 cytokine production, which associated with accumulation of CD206+Tie2+ macrophages, and increased pro-angiogenic cytokines and microvessel density (MVD). Notably, MVD was also increased at diagnosis in the BM of MGUS and SMM patients that subsequently progressed to MM when compared with MGUS and SMM that remained quiescent. These findings suggest a multistep pathogenic process in MM, in which the immune system may contribute to angiogenesis and disease progression. They also suggest initiating a large multicenter study to investigate MVD in asymptomatic patients as prognostic factor for the progression and outcome of this disease. PMID:26155424

Effect of heat transfer on rotating electroosmotic flow through a micro-vessel: haemodynamical applications

NASA Astrophysics Data System (ADS)

Sinha, A.; Mondal, A.; Shit, G. C.; Kundu, P. K.

2016-08-01

This paper theoretically analyzes the heat transfer characteristics associated with electroosmotic flow of blood through a micro-vessel having permeable walls. The analysis is based on the Debye-Hückel approximation for charge distributions and the Navier-Stokes equations are assumed to represent the flow field in a rotating system. The velocity slip condition at the vessel walls is taken into account. The essential features of the rotating electroosmotic flow of blood and associated heat transfer characteristics through a micro-vessel are clearly highlighted by the variation in the non-dimensional flow velocity, volumetric flow rate and non-dimensional temperature profiles. Moreover, the effect of Joule heating parameter and Prandtl number on the thermal transport characteristics are discussed thoroughly. The study reveals that the flow of blood is appreciably influenced by the elctroosmotic parameter as well as rotating Reynolds number.

Three-Dimensional Arrangement of Human Bone Marrow Microvessels Revealed by Immunohistology in Undecalcified Sections

PubMed Central

Wilhelmi, Verena; Seiler, Anja; Lampp, Katrin; Neff, Andreas; Guthe, Michael; Lobachev, Oleg

2016-01-01

The arrangement of microvessels in human bone marrow is so far unknown. We combined monoclonal antibodies against CD34 and against CD141 to visualise all microvessel endothelia in 21 serial sections of about 1 cm2 size derived from a human iliac crest. The specimen was not decalcified and embedded in Technovit® 9100. In different regions of interest, the microvasculature was reconstructed in three dimensions using automatic methods. The three-dimensional models were subject to a rigid semiautomatic and manual quality control. In iliac crest bone marrow, the adipose tissue harbours irregularly distributed haematopoietic areas. These are fed by networks of large sinuses, which are loosely connected to networks of small capillaries prevailing in areas of pure adipose tissue. Our findings are compatible with the hypothesis that capillaries and sinuses in human iliac crest bone marrow are partially arranged in parallel. PMID:27997569

MR Imaging-derived Oxygen Metabolism and Neovascularization Characterization for Grading and IDH Gene Mutation Detection of Gliomas.

PubMed

Stadlbauer, Andreas; Zimmermann, Max; Kitzwögerer, Melitta; Oberndorfer, Stefan; Rössler, Karl; Dörfler, Arnd; Buchfelder, Michael; Heinz, Gertraud

2017-06-01

Purpose To explore the diagnostic performance of physiological magnetic resonance (MR) imaging of oxygen metabolism and neovascularization activity for grading and characterization of isocitrate dehydrogenase (IDH) gene mutation status of gliomas. Materials and Methods This retrospective study had institutional review board approval; written informed consent was obtained from all patients. Eighty-three patients with histopathologically proven glioma (World Health Organization [WHO] grade II-IV) were examined with quantitative blood oxygen level-dependent imaging and vascular architecture mapping. Biomarker maps of neovascularization activity (microvessel radius, microvessel density, and microvessel type indicator [MTI]) and oxygen metabolism (oxygen extraction fraction [OEF] and cerebral metabolic rate of oxygen [CMRO 2 ]) were calculated. Receiver operating characteristic analysis was used to determine diagnostic performance for grading and detection of IDH gene mutation status. Results Low-grade (WHO grade II) glioma showed areas with increased OEF (+18%, P < .001, n = 20), whereas anaplastic glioma (WHO grade III) and glioblastoma (WHO grade IV) showed decreased OEF when compared with normal brain tissue (-54% [P < .001, n = 21] and -49% [P < .001, n = 41], respectively). This allowed clear differentiation between low- and high-grade glioma (area under the receiver operating characteristic curve [AUC], 1) for the patient cohort. MTI had the highest diagnostic performance (AUC, 0.782) for differentiation between gliomas of grades III and IV among all biomarkers. CMRO 2 was decreased (P = .037) in low-grade glioma with a mutated IDH gene, and MTI was significantly increased in glioma grade III with IDH mutation (P = .013) when compared with the IDH wild-type counterparts. CMRO 2 showed the highest diagnostic performance for IDH gene mutation detection in low-grade glioma (AUC, 0.818) and MTI in high-grade glioma (AUC, 0.854) and for all WHO grades (AUC, 0.899) among all biomarkers. Conclusion MR imaging-derived oxygen metabolism and neovascularization characterization may be useful for grading and IDH mutation detection of gliomas and requires only 7 minutes of extra imaging time. © RSNA, 2016 Online supplemental material is available for this article.

Cyclo-oxygenase 2 expression is associated with angiogenesis and lymph node metastasis in human breast cancer.

PubMed

Costa, C; Soares, R; Reis-Filho, J S; Leitão, D; Amendoeira, I; Schmitt, F C

2002-06-01

Cyclo-oxygenases 1 and 2 (COX-1 and COX-2) are key enzymes in prostaglandin biosynthesis. COX-2 is induced by a wide variety of stimuli, and present during inflammation. COX-2 overexpression has been observed in colon, head and neck, lung, prostate, stomach, and breast cancer. In colon and gastric cancer, COX-2 expression was associated with angiogenesis. The aim of this study was to determine the relation between COX-2 expression and angiogenesis in breast cancer, and to correlate the expression of this enzyme with classic clinicopathological parameters. COX-2 expression was investigated by immunohistochemistry and western blotting analysis. The expression of COX-2 was then related to age, histological grade, nodal status, oestrogen receptor status, p53 expression,c-erb-B2 overexpression, mitotic counts, MIB-1 labelling index, apoptotic index, sialyl-Tn expression, transforming growth factor alpha expression, microvessel density, and disease free survival in 46 patients with invasive ductal breast carcinoma. By means of immunohistochemistry, COX-2 expression was detected in eight of the 46 carcinomas studied. Western blotting showed COX-2 protein expression in the same breast tumours, but not in normal adjacent tissues. The density of microvessels immunostained with anti-F-VIII related antigen was significantly higher in patients with COX-2 expression than in those without expression (p = 0.03). In addition, COX-2 was significantly associated with the presence of sialyl-Tn expression (p = 0.02), lymph node metastasis (p = 0.03), a high apoptotic index (p = 0.03), and a short disease free survival (p = 0.03) in univariate analyses. These data suggest that COX-2 expression is associated with angiogenesis, lymph node metastasis, and apoptosis in human breast cancer. Moreover, these results warrant further studies with larger series of patients to confirm the association with short disease free survival in patients with breast cancer.

Role of Neuropilin-1/Semaphorin-3A signaling in the functional and morphological integrity of the cochlea

PubMed Central

Salehi, Pezhman; Gundimeda, Usha; Lael Cantu, Homero; Lavinsky, Joel; Myint, Anthony; Wang, Juemei; Abdala, Carolina; Ohyama, Takahiro; Coate, Thomas Matthew

2017-01-01

Neuropilin-1 (Nrp1) encodes the transmembrane cellular receptor neuropilin-1, which is associated with cardiovascular and neuronal development and was within the peak SNP interval on chromosome 8 in our prior GWAS study on age-related hearing loss (ARHL) in mice. In this study, we generated and characterized an inner ear-specific Nrp1 conditional knockout (CKO) mouse line because Nrp1 constitutive knockouts are embryonic lethal. In situ hybridization demonstrated weak Nrp1 mRNA expression late in embryonic cochlear development, but increased expression in early postnatal stages when cochlear hair cell innervation patterns have been shown to mature. At postnatal day 5, Nrp1 CKO mice showed disorganized outer spiral bundles and enlarged microvessels of the stria vascularis (SV) but normal spiral ganglion cell (SGN) density and presynaptic ribbon body counts; however, we observed enlarged SV microvessels, reduced SGN density, and a reduction of presynaptic ribbons in the outer hair cell region of 4-month-old Nrp1 CKO mice. In addition, we demonstrated elevated hearing thresholds of the 2-month-old and 4-month-old Nrp1 CKO mice at frequencies ranging from 4 to 32kHz when compared to 2-month-old mice. These data suggest that conditional loss of Nrp1 in the inner ear leads to progressive hearing loss in mice. We also demonstrated that mice with a truncated variant of Nrp1 show cochlear axon guidance defects and that exogenous semaphorin-3A, a known neuropilin-1 receptor agonist, repels SGN axons in vitro. These data suggest that Neuropilin-1/Semaphorin-3A signaling may also serve a role in neuronal pathfinding in the developing cochlea. In summary, our results here support a model whereby Neuropilin-1/Semaphorin-3A signaling is critical for the functional and morphological integrity of the cochlea and that Nrp1 may play a role in ARHL. PMID:29059194

An analysis of microvessel density, androgen receptor, p53 and HER-2/neu expression and Gleason score in prostate cancer . preliminary results and therapeutic implications.

PubMed

Mydlo, J H; Kral, J G; Volpe, M; Axotis, C; Macchia, R J; Pertschuk, L P

1998-01-01

To investigate relationships between microvessel density (MVD), androgen receptors (AR), mutant p53 and HER-2/neu expression and Gleason score (GS) to further understand the tumor biology of prostate cancer (CAP). Slides of CAP from patients who underwent radical prostatectomy or channel transurethral resection of the prostate (TURP) were tested for androgen receptors by immunocytochemical assay and MVD was analyzed by staining with antibodies to the endothelial cell membrane molecule PECAM-1/CD-31. The p53 monoclonal antibody D07 and HER-2 9G6 mouse monoclonal antibody were used to assess p53 and HER-2/neu expression, respectively. The results were correlated with GS and clinical stage by multivariate analysis. We found a fourfold greater expression of MVD in prostate cancer specimens compared to neighboring normal prostate tissue. We observed a greater concentration of MVD in the higher Gleason scores (r = 0.40, p = 0. 06), and a correlation of Gleason score with mutant p53 expression (r = 0.57, p <0.05). We did not observe any associations between AR or HER-2/neu to Gleason score. More than half of the patients with specimens with 50% or greater expression of mutant p53 were in stage D2 (T4NxM1b) at the time of biopsy. We observed a correlation between mutant p53 and GS, and a greater concentration of MVD in the higher GS. Since the neovascularity of prostate tumors can be attenuated by radiation and hormones, while mutant p53 may confer resistance to such treatment, it appears that p53 expression may also play an important role in addition to angiogenesis in the virulence of prostate cancer. These data may aid in allocating patients to different treatment modalities.

Mesenchymal stem cell-based NK4 gene therapy in nude mice bearing gastric cancer xenografts

PubMed Central

Zhu, Yin; Cheng, Ming; Yang, Zhen; Zeng, Chun-Yan; Chen, Jiang; Xie, Yong; Luo, Shi-Wen; Zhang, Kun-He; Zhou, Shu-Feng; Lu, Nong-Hua

2014-01-01

Mesenchymal stem cells (MSCs) have been recognized as promising delivery vehicles for gene therapy of tumors. Gastric cancer is the third leading cause of worldwide cancer mortality, and novel treatment modalities are urgently needed. NK4 is an antagonist of hepatocyte growth factor receptors (Met) which are often aberrantly activated in gastric cancer and thus represent a useful candidate for targeted therapies. This study investigated MSC-delivered NK4 gene therapy in nude mice bearing gastric cancer xenografts. MSCs were transduced with lentiviral vectors carrying NK4 complementary DNA or enhanced green fluorescent protein (GFP). Such transduction did not change the phenotype of MSCs. Gastric cancer xenografts were established in BALB/C nude mice, and the mice were treated with phosphate-buffered saline (PBS), MSCs-GFP, Lenti-NK4, or MSCs-NK4. The tropism of MSCs toward gastric cancer cells was determined by an in vitro migration assay using MKN45 cells, GES-1 cells and human fibroblasts and their presence in tumor xenografts. Tumor growth, tumor cell apoptosis and intratumoral microvessel density of tumor tissue were measured in nude mice bearing gastric cancer xenografts treated with PBS, MSCs-GFP, Lenti-NK4, or MSCs-NK4 via tail vein injection. The results showed that MSCs migrated preferably to gastric cancer cells in vitro. Systemic MSCs-NK4 injection significantly suppressed the growth of gastric cancer xenografts. MSCs-NK4 migrated and accumulated in tumor tissues after systemic injection. The microvessel density of tumor xenografts was decreased, and tumor cellular apoptosis was significantly induced in the mice treated with MSCs-NK4 compared to control mice. These findings demonstrate that MSC-based NK4 gene therapy can obviously inhibit the growth of gastric cancer xenografts, and MSCs are a better vehicle for NK4 gene therapy than lentiviral vectors. Further studies are warranted to explore the efficacy and safety of the MSC-based NK4 gene therapy in animals and cancer patients. PMID:25525335

5-fluorouracil enhances the antitumor effect of sorafenib and sunitinib in a xenograft model of human renal cell carcinoma.

PubMed

Miyake, Makito; Anai, Satoshi; Fujimoto, Kiyohide; Ohnishi, Sayuri; Kuwada, Masaomi; Nakai, Yasushi; Inoue, Takeshi; Tomioka, Atsushi; Tanaka, Nobumichi; Hirao, Yoshihiko

2012-06-01

Sorafenib and sunitinib are multi-kinase inhibitors with antitumor activity in patients with advanced renal cell carcinoma (RCC). Several studies have evaluated the effect of sorafenib/sunitinib in combination with chemotherapeutic agents in different types of tumor. However, few studies have addressed the activity of fluorinated pyrimidine in combination with sorafenib/sunitinib. In this study, we examined the potential of combination therapy with 5FU and sorafenib/sunitinib in human RCC cell lines. Three human RCC cell lines, ACHN, Caki-1 and Caki-2, were used to assess sensitivity to 5-fluorouracil (5FU), sorafenib and sunitinib alone or in combination using an in vitro cell survival assay. Caki-2 cells demonstrated significantly higher resistance to 5FU and sorafenib as compared to ACHN and Caki-1. Additive antitumor effects of the combination therapy were observed in the in vitro study. There was a tendency for a positive correlation between the sensitivity to sunitinib and platelet-derived growth factor β (PDGFR-β) expression levels, which were examined by reverse transcription polymerase chain reaction. Caki-1 xenograft models were prepared by inoculating cells subcutaneously into nude mice, which were divided randomly into six groups: control, 5FU (8 mg/kg/day, intraperitoneally), sorafenib (15 mg/kg/day, orally), sunitinib (20 mg/kg/day, orally), and 5FU with sorafenib or sunitinib. The treatments were administered on 5 days each week, and tumor growth was monitored for 42 days following inoculation of cells. Synergistic antitumor effects of the combination therapy were observed in an in vivo study. The resected tumors were evaluated using the Ki-67 labeling index and microvessel density. Both the Ki-67 labeling index and microvessel density were decreased in tumors treated with the combination therapy compared to those treated with sorafenib/sunitinib alone. These findings suggest that the combination therapy of 5FU with sorafenib/sunitinib may be an effective therapeutic modality for advanced RCC patients.

A mathematical model for filtration and macromolecule transport across capillary walls.

PubMed

Facchini, L; Bellin, A; Toro, E F

2014-07-01

Metabolic substrates, such as oxygen and glucose, are rapidly delivered to the cells of large organisms through filtration across microvessels walls. Modelling this important process is complicated by the strong coupling between flow and transport equations, which are linked through the osmotic pressure induced by the colloidal plasma proteins. The microvessel wall is a composite media with the internal glycocalyx layer exerting a strong sieving effect on macromolecules, with respect to the external layer composed by the endothelial cells. The physiological structure of the microvessel is represented as the superimposition of two membranes with different properties; the inner membrane represents the glycocalyx, while the outer membrane represents the surrounding endothelial cells. Application of the mass conservation principle and thermodynamic considerations lead to a model composed of two coupled second-order ordinary differential equations for the hydrostatic and osmotic pressures, one, expressing volumetric mass conservation and the other, which is non-linear in the unknown osmotic pressure, expressing macromolecules mass conservation. Despite the complexity of the system, the assumption that the properties of the layers are piece-wise constant allows us to obtain analytical solutions for the two pressures. This solution is in agreement with experimental observations, which contrary to common belief, show that flow reversal cannot occur in steady-state conditions unless the hydrostatic pressure in the lumen drops below physiologically plausible values. The observed variations of the volumetric flux and the solute mass flux in case of a significant reduction of the hydrostatic pressure at the lumen are in qualitative agreement with observed variations during detailed experiments reported in the literature. On the other hand, homogenising the microvessel wall into a single-layer membrane with equivalent properties leads to a very different distribution of pressure across the microvessel walls, not consistent with observations. Copyright © 2014 Elsevier Inc. All rights reserved.

Expression of protease-activated receptor-2 (PAR-2) in patients with nasopharyngeal carcinoma: correlation with clinicopathological features and prognosis.

PubMed

Li, Zhi; Bian, Li-Juan; Li, Yang; Liang, Ying-Jie; Liang, Hui-Zhen

2009-01-01

We aimed at determining whether the expression of protease-activated receptor 2 (PAR-2) is involved in the progression of nasopharyngeal carcinoma (NPC) and correlated with latent membrane protein 1 (LMP-1), matrix metalloproteinases-9 (MMP9), and angiogenesis of tumor. PAR-2, LMP-1, and MMP9 expressions were detected in 57 biopsies of primary NPC by immunohistochemistry. The presence of Epstein-Barr virus (EBV) was determined using EBER in situ hybridization, and intratumoral microvessels were highlighted by staining endothelial cells for anti-CD34. The correlations with immunostainings and clinicopathological factors, as well as the follow-up data of patients, were analyzed statistically. Strong expression of PAR-2 in 61.4% (35/57) of the biopsies was correlated with extensive lymph node metastasis and advanced stage of NPC. The patients with PAR-2/LMP-1 or PAR-2/MMP9 dual high-expression tumors had a significant worse prognosis than those with single protein high expression and dual low or negative expression tumors (P=0.013 and 0.004, respectively). Angiogenesis in the tumor is related to overall survival of NPC patients (P=0.001), and exhibits strong PAR-2 expression or LMP-1 expression in tumors associated with increased intratumoral microvessel density (P=0.026 and 0.006, respectively). PAR-2 is a possible mediator cooperating with LMP-1 and MMP9 to influence the progression of NPC by inducing angiogenesis and promoting lymph node metastasis.

Expression of lactoferrin receptors is increased in the mesencephalon of patients with Parkinson disease.

PubMed Central

Faucheux, B A; Nillesse, N; Damier, P; Spik, G; Mouatt-Prigent, A; Pierce, A; Leveugle, B; Kubis, N; Hauw, J J; Agid, Y

1995-01-01

The degeneration of nigral dopaminergic neurons in Parkinson disease is believed to be associated with oxidative stress. Since iron levels are increased in the substantia nigra of parkinsonian patients and this metal catalyzes the formation of free radicals, it may be involved in the mechanisms of nerve cell death. The cause of nigral iron increase is not understood. Iron acquisition by neurons may occur from iron-transferrin complexes with a direct interaction with specific membrane receptors, but recent results have shown a low density of transferrin receptors in the substantia nigra. To investigate whether neuronal death in Parkinson disease may be associated with changes in a pathway supplementary to that of transferrin, lactoferrin (lactotransferrin) receptor expression was studied in the mesencephalon. In this report we present evidence from immunohistochemical staining of postmortem human brain tissue that lactoferrin receptors are localized on neurons (perikarya, dendrites, axons), cerebral microvasculature, and, in some cases, glial cells. In parkinsonian patients, lactoferrin receptor immunoreactivity on neurons and microvessels was increased and more pronounced in those regions of the mesencephalon where the loss of dopaminergic neurons is severe. Moreover, in the substantia nigra, the intensity of immunoreactivity on neurons and microvessels was higher for patients with higher nigral dopaminergic loss. These data suggest that lactoferrin receptors on vulnerable neurons may increase intraneuronal iron levels and contribute to the degeneration of nigral dopaminergic neurons in Parkinson disease. Images Fig. 1 Fig. 2 PMID:7568181

Occlusion and rupture of ex vivo capillary bifurcation due to acoustic droplet vaporization

NASA Astrophysics Data System (ADS)

Feng, Yi; Qin, Dui; Zhang, Jun; Zhang, Lei; Bouakaz, Ayache; Wan, Mingxi

2018-06-01

Gas embolotherapy (GE) consists in the occlusion of tumor blood vessels using gas emboli induced by acoustic droplet vaporization (ADV), to create tumor starvation and localized drug delivery. Therefore, the occlusion and rupture of capillary bifurcation due to ADV was investigated in an ex vivo rat mesentery model using a confocal acousto-optical high-speed microscope system. Following ADV bubble formation, coalescence, and translational movement, the growing bubbles lodged in and then occluded two different capillary bifurcations. Capillary rupture was induced at the bubble lodging area, immediately followed by gas extravasation and bubble dislodging. Before and after bubble lodgment/occlusion, a local microvessel invagination was observed due to the interactions between ADV bubbles and the microvessel itself, indicating a contribution to the capillary rupture. Understanding the transient dynamics of ADV bubble, the bubble-microvessel interaction and the consequent mechanical bio-effects in GE is of the paramount importance for developing and applying this approach in clinical practice.

Brain-endocrine interactions: a microvascular route in the mediobasal hypothalamus.

PubMed

Ciofi, Philippe; Garret, Maurice; Lapirot, Olivier; Lafon, Pierrette; Loyens, Anne; Prévot, Vincent; Levine, Jon E

2009-12-01

Blood-borne hormones acting in the mediobasal hypothalamus, like those controlling food intake, require relatively direct access to target chemosensory neurons of the arcuate nucleus (ARC). An anatomical substrate for this is a permeable microvasculature with fenestrated endothelial cells in the ARC, a system that has awaited comprehensive documentation. Here, the immunofluorescent detection of endothelial fenestral diaphragms in the rat ARC allowed us to quantitate permeable microvessels throughout its rostrocaudal extent. We have determined that permeable microvessels are part of the subependymal plexus irrigating exclusively the ventromedial (vm) ARC from the subadjacent neuroendocrine median eminence. Unexpectedly, permeable microvessels were concentrated proximal to the pituitary stalk. This marked topography strongly supports the functional importance of retrograde blood flow from the pituitary to the vmARC, therefore making a functional relationship between peripheral long-loop, pituitary short-loop, and neuroendocrine ultra-short loop feedback, altogether converging for integration in the vmARC (formerly known as the hypophysiotrophic area), thereby so pivotal as a multicompetent brain endocrinostat.

AutoTag and AutoSnap: Standardized, semi-automatic capture of regions of interest from whole slide images

PubMed Central

Marien, Koen M.; Andries, Luc; De Schepper, Stefanie; Kockx, Mark M.; De Meyer, Guido R.Y.

2015-01-01

Tumor angiogenesis is measured by counting microvessels in tissue sections at high power magnification as a potential prognostic or predictive biomarker. Until now, regions of interest1 (ROIs) were selected by manual operations within a tumor by using a systematic uniform random sampling2 (SURS) approach. Although SURS is the most reliable sampling method, it implies a high workload. However, SURS can be semi-automated and in this way contribute to the development of a validated quantification method for microvessel counting in the clinical setting. Here, we report a method to use semi-automated SURS for microvessel counting: • Whole slide imaging with Pannoramic SCAN (3DHISTECH) • Computer-assisted sampling in Pannoramic Viewer (3DHISTECH) extended by two self-written AutoHotkey applications (AutoTag and AutoSnap) • The use of digital grids in Photoshop® and Bridge® (Adobe Systems) This rapid procedure allows traceability essential for high throughput protein analysis of immunohistochemically stained tissue. PMID:26150998

Hemodynamic and proinflammatory actions of endothelin-1 in guinea pig small intestine submucosal microcirculation.

PubMed

King-VanVlack, C E; Mewburn, J D; Chapler, C K; MacDonald, P H

2003-06-01

The hemodynamic and proinflammatory effects of endothelin-1 (ET-1) in proximal (1st/2nd order) and terminal (3rd/4th order) arterioles and venules were examined in small intestine submucosa of anesthetized guinea pigs. Vessel diameter (D), red blood cell velocity, and blood flow (Q) were determined in eight proximal and eight terminal microvessels before and at 20 min of ET-1 suffusion (10(-10), 10(-9), and 10(-8) M) and then with endothelin-A (ET(A))-receptor blockade with BQ-123 (10(-5) M). This protocol was repeated with platelet-activating factor (PAF) inhibition (WEB-2086, 1.0 mg/kg iv; n = 16). The ET-1-mediated microvascular responses were also examined with endothelin-B (ET(B))-receptor blockade using BQ-788 (10(-5) M; n = 11) alone or with ET(A+B)-receptor blockade with BQ-123 + BQ-788 (n = 10). Microvascular permeability was assessed by FITC-albumin (25 mg/kg iv) extravasation in seven series: 1) buffered modified Krebs solution suffusion (n = 6), 2) histamine suffusion (HIS; 10(-3) M, n = 5), 3) ET-1 suffusion (10(-8) M, n = 5), 4) BQ-123 (10(-5) M) plus ET-1 suffusion (n = 5), 5) PAF inhibition before ET-1 suffusion (n = 5), 6) histamine-1 (H1)-receptor blockade (diphenhydramine, 20 mg/kg iv) before ET-1 suffusion (n = 5), and 7) ET(B)-receptor blockade before (BQ-788 10(-5) M; n = 3) or with ET-1 suffusion (n = 3). D and Q decreased at 10(-8) M ET-1 and returned to control values with BQ-123 and BQ-123+BQ788 but not with BQ-788 in proximal microvessels. D did not change in terminal microvessels with ET-1 (10(-8) M) but decreased with BQ-788 and increased with BQ-123. PAF inhibition did not affect the D and Q responses of proximal microvessels to ET-1 but prevented the fall in Q in terminal microvessels with ET-1. ET-1 increased vascular permeability to approximately 1/3 of that with HIS; this response was prevented with BQ-123 and WEB-2086 but not with H1-receptor blockade. This is the first evidence that submucosal terminal microvessel flow is reduced with ET-1 independent of vessel diameter changes and that this response is associated with increased microvascular permeability mediated via ET(A)-receptor stimulation and PAF activation.

VHL deletion impairs mammary alveologenesis but is not sufficient for mammary tumorigenesis.

PubMed

Seagroves, Tiffany N; Peacock, Danielle L; Liao, Debbie; Schwab, Luciana P; Krueger, Robin; Handorf, Charles R; Haase, Volker H; Johnson, Randall S

2010-05-01

Overexpression of hypoxia inducible factor-1 (HIF-1)alpha, which is common in most solid tumors, correlates with poor prognosis and high metastatic risk in breast cancer patients. Because HIF-1alpha protein stability is tightly controlled by the tumor suppressor von Hippel-Lindau (VHL), deletion of VHL results in constitutive HIF-1alpha expression. To determine whether VHL plays a role in normal mammary gland development, and if HIF-1alpha overexpression is sufficient to initiate breast cancer, Vhl was conditionally deleted in the mammary epithelium using the Cre/loxP system. During first pregnancy, loss of Vhl resulted in decreased mammary epithelial cell proliferation and impaired alveolar differentiation; despite these phenotypes, lactation was sufficient to support pup growth. In contrast, in multiparous dams, Vhl(-/-) mammary glands exhibited a progressive loss of alveolar epithelium, culminating in lactation failure. Deletion of Vhl in the epithelium also impacted the mammary stroma, as there was increased microvessel density accompanied by hemorrhage and increased immune cell infiltration. However, deletion of Vhl was not sufficient to induce mammary tumorigenesis in dams bred continuously for up to 24 months of age. Moreover, co-deletion of Hif1a could not rescue the Vhl(-/-)-dependent phenotype as dams were unable to successfully lactate during the first lactation. These results suggest that additional VHL-regulated genes besides HIF1A function to maintain the proliferative and regenerative potential of the breast epithelium.

The effect of riboflavin/UVA cross-linking on anti-degeneration and promoting angiogenic capability of decellularized liver matrix.

PubMed

Xiang, Junxi; Liu, Peng; Zheng, Xinglong; Dong, Dinghui; Fan, Shujuan; Dong, Jian; Zhang, Xufeng; Liu, Xuemin; Wang, Bo; Lv, Yi

2017-10-01

Weak mechanical property and unstable degradation rate limited the application of decellularized liver matrix in tissue engineering. The aim of this study was to explore a new method for improving the mechanical properties, anti-degeneration and angiogenic capability of decellularized liver matrix. This was achieved by a novel approach using riboflavin/ultraviolet A treatment to induce collagen cross-linking of decellularized matrix. Histological staining and scanning electron microscope showed that the diameter of cross-linked fibers significantly increased compared with the control group. The average peak load and Young's modulus of decellularized matrix were obviously improved after cross-linking. Then we implanted the modified matrix into the rat hepatic injury model to test the anti-degeneration and angiogenic capability of riboflavin/UVA cross-linked decellularized liver scaffolds in vivo. The results indicated that cross-linked scaffolds degrade more slowly than those in the control group. In the experiment group, average microvessel density in the implanted matrix was higher than that in the control group since the first week after implantation. In conclusion, we initiated the method to improve the biomechanical properties of decellularized liver scaffolds by riboflavin/UVA cross-linking, and more importantly, its improvement on anti-degeneration and angiogenesis was identified. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2662-2669, 2017. © 2017 Wiley Periodicals, Inc.

Sialic acids regulate microvessel permeability, revealed by novel in vivo studies of endothelial glycocalyx structure and function

PubMed Central

Betteridge, Kai B.; Arkill, Kenton P.; Neal, Christopher R.; Harper, Steven J.; Foster, Rebecca R.; Satchell, Simon C.; Bates, David O.

2017-01-01

Key points We have developed novel techniques for paired, direct, real‐time in vivo quantification of endothelial glycocalyx structure and associated microvessel permeability.Commonly used imaging and analysis techniques yield measurements of endothelial glycocalyx depth that vary by over an order of magnitude within the same vessel.The anatomical distance between maximal glycocalyx label and maximal endothelial cell plasma membrane label provides the most sensitive and reliable measure of endothelial glycocalyx depth.Sialic acid residues of the endothelial glycocalyx regulate glycocalyx structure and microvessel permeability to both water and albumin. Abstract The endothelial glycocalyx forms a continuous coat over the luminal surface of all vessels, and regulates multiple vascular functions. The contribution of individual components of the endothelial glycocalyx to one critical vascular function, microvascular permeability, remains unclear. We developed novel, real‐time, paired methodologies to study the contribution of sialic acids within the endothelial glycocalyx to the structural and functional permeability properties of the same microvessel in vivo. Single perfused rat mesenteric microvessels were perfused with fluorescent endothelial cell membrane and glycocalyx labels, and imaged with confocal microscopy. A broad range of glycocalyx depth measurements (0.17–3.02 μm) were obtained with different labels, imaging techniques and analysis methods. The distance between peak cell membrane and peak glycocalyx label provided the most reliable measure of endothelial glycocalyx anatomy, correlating with paired, numerically smaller values of endothelial glycocalyx depth (0.078 ± 0.016 μm) from electron micrographs of the same portion of the same vessel. Disruption of sialic acid residues within the endothelial glycocalyx using neuraminidase perfusion decreased endothelial glycocalyx depth and increased apparent solute permeability to albumin in the same vessels in a time‐dependent manner, with changes in all three true vessel wall permeability coefficients (hydraulic conductivity, reflection coefficient and diffusive solute permeability). These novel technologies expand the range of techniques that permit direct studies of the structure of the endothelial glycocalyx and dependent microvascular functions in vivo, and demonstrate that sialic acid residues within the endothelial glycocalyx are critical regulators of microvascular permeability to both water and albumin. PMID:28524373

PPARδ agonist GW501516 prevents uncoupling of endothelial nitric oxide synthase in cerebral microvessels of hph-1 mice

PubMed Central

Santhanam, Anantha Vijay R.; d’Uscio, Livius V.; He, Tongrong; Katusic, Zvonimir S.

2012-01-01

Peroxisome proliferator-activated receptor delta (PPARδ) is ubiquitously expressed in the vasculature, including cerebral circulation. The role of PPARδ in metabolism of tetrahydrobiopterin (BH4) has not been studied in the cerebral microvasculature. In the present study, the effects of PPARδ agonist GW501516 on uncoupling of endothelial nitric oxide synthase (eNOS) were determined in cerebral microvessels of BH4-deficient hph-1 mice. Wild-type (B6CBA) and hph-1 mice were orally gavaged with a selective PPARδ activator, GW501516 (2 mg/kg/day) for 14 days, and thereafter, cerebral microvessels were isolated and studied. Treatment of hph-1 mice with GW501516 significantly reduced oxidation of BH4 and increased the ratio of BH4 to 7,8-BH2 (P<0.05, n=6–9). Attenuation of L-NAME-inhibitable superoxide anion levels by GW501516 demonstrated that activation of PPARδ might prevent uncoupling of endothelial nitric oxide synthase (eNOS, P<0.05, n=6–9). Western blotting studies demonstrated that GW501516 selectively increased the endothelial expressions of CuZn superoxide dismutase (P<0.05, n=6–9) and catalase (P<0.05, n=6–8). PPARδ activation increased the total nitrite and nitrate (NO2 + NO3) content in cerebral microvessels (P<0.05, n=6). Obtained results suggest that in vivo activation of PPARδ prevents eNOS uncoupling, restores bioavailability of NO and may help preserve endothelial function in the BH4-deficient cerebral circulation. PMID:22982594

PPARδ agonist GW501516 prevents uncoupling of endothelial nitric oxide synthase in cerebral microvessels of hph-1 mice.

PubMed

Santhanam, Anantha Vijay R; d'Uscio, Livius V; He, Tongrong; Katusic, Zvonimir S

2012-11-05

Peroxisome proliferator-activated receptor delta (PPARδ) is ubiquitously expressed in the vasculature, including cerebral circulation. The role of PPARδ in metabolism of tetrahydrobiopterin (BH₄) has not been studied in the cerebral microvasculature. In the present study, the effects of PPARδ agonist GW501516 on uncoupling of endothelial nitric oxide synthase (eNOS) were determined in cerebral microvessels of BH₄-deficient hph-1 mice. Wild-type (B6CBA) and hph-1 mice were orally gavaged with a selective PPARδ activator, GW501516 (2 mg/kg/day) for 14 days, and thereafter, cerebral microvessels were isolated and studied. Treatment of hph-1 mice with GW501516 significantly reduced oxidation of BH₄ and increased the ratio of BH₄ to 7,8-BH₂ (P<0.05, n=6-9). Attenuation of L-NAME-inhibitable superoxide anion levels by GW501516 demonstrated that activation of PPARδ might prevent uncoupling of endothelial nitric oxide synthase (eNOS, P<0.05, n=6-9). Western blotting studies demonstrated that GW501516 selectively increased the endothelial expressions of CuZn superoxide dismutase (P<0.05, n=6-9) and catalase (P<0.05, n=6-8). PPARδ activation increased the total nitrite and nitrate (NO₂+NO₃) content in cerebral microvessels (P<0.05, n=6). Obtained results suggest that in vivo activation of PPARδ prevents eNOS uncoupling, restores bioavailability of NO and may help preserve endothelial function in the BH₄-deficient cerebral circulation. Copyright © 2012 Elsevier B.V. All rights reserved.

Data-driven sampling method for building 3D anatomical models from serial histology

NASA Astrophysics Data System (ADS)

Salunke, Snehal Ulhas; Ablove, Tova; Danforth, Theresa; Tomaszewski, John; Doyle, Scott

2017-03-01

In this work, we investigate the effect of slice sampling on 3D models of tissue architecture using serial histopathology. We present a method for using a single fully-sectioned tissue block as pilot data, whereby we build a fully-realized 3D model and then determine the optimal set of slices needed to reconstruct the salient features of the model objects under biological investigation. In our work, we are interested in the 3D reconstruction of microvessel architecture in the trigone region between the vagina and the bladder. This region serves as a potential avenue for drug delivery to treat bladder infection. We collect and co-register 23 serial sections of CD31-stained tissue images (6 μm thick sections), from which four microvessels are selected for analysis. To build each model, we perform semi-automatic segmentation of the microvessels. Subsampled meshes are then created by removing slices from the stack, interpolating the missing data, and re-constructing the mesh. We calculate the Hausdorff distance between the full and subsampled meshes to determine the optimal sampling rate for the modeled structures. In our application, we found that a sampling rate of 50% (corresponding to just 12 slices) was sufficient to recreate the structure of the microvessels without significant deviation from the fullyrendered mesh. This pipeline effectively minimizes the number of histopathology slides required for 3D model reconstruction, and can be utilized to either (1) reduce the overall costs of a project, or (2) enable additional analysis on the intermediate slides.

Butter feeding enhances TNF-alpha production from macrophages and lymphocyte adherence in murine small intestinal microvessels.

PubMed

Fujiyama, Yoichi; Hokari, Ryota; Miura, Soichiro; Watanabe, Chikako; Komoto, Shunsuke; Oyama, Tokushige; Kurihara, Chie; Nagata, Hiroshi; Hibi, Toshifumi

2007-11-01

Dietary fat is known to modulate immune functions. Intake of an animal fat-rich diet has been linked to increased risk of inflammation; however, little is known about how animal fat ingestion directly affects intestinal immune function. The objective of this study was to assess the effect of butter feeding on lymphocyte migration in intestinal mucosa and the changes in adhesion molecules and cytokines involved in this effect. T-lymphocytes isolated from the spleen were fluorescence-labeled and injected into recipient mice. Butter was administered into the duodenum, and villus microvessels of the small intestinal mucosa were observed under an intravital microscope. mRNA expression of adhesion molecules and cytokines in the intestinal mucosa were determined by quantitative PCR. The effect of butter feeding on tumor necrosis factor (TNF)-alpha mRNA expression of intestinal macrophages was also determined. Intraluminal butter administration significantly increased lymphocyte adherence to intestinal microvessels accompanied by increases in expression levels of adhesion molecules ICAM-1, MAdCAM-1 and VCAM-1. This accumulation was significantly attenuated by anti-MAdCAM-1 and anti-ICAM-1 antibodies. Butter administration significantly increased TNF-alpha in the lamina proprial macrophages but not interleukin-6. Anti-TNF-alpha treatment attenuated the enhanced expression of adhesion molecules induced by butter administration. T-lymphocyte adherence to microvessels of the small intestinal mucosa was significantly enhanced after butter ingestion. This enhancement is due to increase in expression levels of adhesion molecules of the intestinal mucosa, which is mediated by TNF-alpha from macrophages in the intestinal lamina propria.

Bioprinted Amniotic Fluid-Derived Stem Cells Accelerate Healing of Large Skin Wounds

PubMed Central

Skardal, Aleksander; Mack, David; Kapetanovic, Edi; Atala, Anthony; Jackson, John D.; Yoo, James

2012-01-01

Stem cells obtained from amniotic fluid show high proliferative capacity in culture and multilineage differentiation potential. Because of the lack of significant immunogenicity and the ability of the amniotic fluid-derived stem (AFS) cells to modulate the inflammatory response, we investigated whether they could augment wound healing in a mouse model of skin regeneration. We used bioprinting technology to treat full-thickness skin wounds in nu/nu mice. AFS cells and bone marrow-derived mesenchymal stem cells (MSCs) were resuspended in fibrin-collagen gel and “printed” over the wound site. At days 0, 7, and 14, AFS cell- and MSC-driven wound closure and re-epithelialization were significantly greater than closure and re-epithelialization in wounds treated by fibrin-collagen gel only. Histological examination showed increased microvessel density and capillary diameters in the AFS cell-treated wounds compared with the MSC-treated wounds, whereas the skin treated only with gel showed the lowest amount of microvessels. However, tracking of fluorescently labeled AFS cells and MSCs revealed that the cells remained transiently and did not permanently integrate in the tissue. These observations suggest that the increased wound closure rates and angiogenesis may be due to delivery of secreted trophic factors, rather than direct cell-cell interactions. Accordingly, we performed proteomic analysis, which showed that AFS cells secreted a number of growth factors at concentrations higher than those of MSCs. In parallel, we showed that AFS cell-conditioned media induced endothelial cell migration in vitro. Taken together, our results indicate that bioprinting AFS cells could be an effective treatment for large-scale wounds and burns. PMID:23197691

Transfection of the Human Heme Oxygenase Gene Into Rabbit Coronary Microvessel Endothelial Cells: Protective Effect Against Heme and Hemoglobin Toxicity

NASA Astrophysics Data System (ADS)

Abraham, N. G.; Lavrovsky, Y.; Schwartzman, M. L.; Stoltz, R. A.; Levere, R. D.; Gerritsen, M. E.

1995-07-01

Heme oxygenase (HO) is a stress protein and has been suggested to participate in defense mechanisms against agents that may induce oxidative injury such as metals, endotoxin, heme/hemoglobin, and various cytokines. Overexpression of HO in cells might therefore protect against oxidative stress produced by certain of these agents, specifically heme and hemoglobin, by catalyzing their degradation to bilirubin, which itself has antioxidant properties. We report here the successful in vitro transfection of rabbit coronary microvessel endothelial cells with a functioning gene encoding the human HO enzyme. A plasmid containing the cytomegalovirus promoter and the human HO cDNA complexed to cationic liposomes (Lipofectin) was used to transfect rabbit endothelial cells. Cells transfected with human HO exhibited an ≈3.0-fold increase in enzyme activity and expressed a severalfold induction of human HO mRNA as compared with endogenous rabbit HO mRNA. Transfected and nontransfected cells expressed factor VIII antigen and exhibited similar acetylated low-density lipoprotein uptake (two important features that characterize endothelial cells) with >85% of cells staining positive for each marker. Moreover, cells transfected with the human HO gene acquired substantial resistance to toxicity produced by exposure to recombinant hemoglobin and heme as compared with nontransfected cells. The protective effect of HO overexpression against heme/hemoglobin toxicity in endothelial cells shown in these studies provides direct evidence that the inductive response of human HO to such injurious stimuli represents an important tissue adaptive mechanism for moderating the severity of cell damage produced by these blood components.

Aberrant expression of decoy receptor 3 in human breast cancer: relevance to lymphangiogenesis.

PubMed

Wu, Qiuwan; Zheng, Yahong; Chen, Donghan; Li, Xiaohong; Lu, Chuanhui; Zhang, Zhiming

2014-05-15

Decoy receptor 3 (DcR3), a decoy receptor against Fas ligand belonging to the tumor necrosis factor receptor superfamily, is overexpressed in some forms of cancer. It was recently reported that DcR3 could protect endothelial cells from apoptosis, implying a potential role in the development of vessels, whereas its role in the lymphangiogenesis remains unclear. In the present study, we studied the DcR3 expression and its relationship with the lymphatic microvessel density (LMVD) to investigate if it played a role in the lymph metastasis of human breast cancer. Real-time polymerase chain reaction and immunohistochemistry were performed to measure the messenger RNA and protein expression of DcR3 in the breast cancer tissues, noncancerous counterparts, and axillary lymph node from 63 patients. LMVD in these specimens was assessed by counting the D2-40 labeled-microvessels. Furthermore, the correlations between DcR3 expression and LMVD and other clinicopathologic parameters were analyzed. DcR3 was overexpressed in the breast cancer tissue of 58 patients (92.1%) and was also expressed in vascular endothelial cells and tumor cells in the lymph nodes. LMVD in cancer tissue and lymph nodes were both positively correlated to the aberrant expression of DcR3. The relevance between DcR3 overexpression and LMVD revealed the existence of possible links between DcR3 and lymphangiogenesis. Based on these findings, it is important to further explore the regulation of lymphangiogenesis operated by the reverse tumor necrosis factor signaling of DcR3. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Microvascular Perfusion Changes following Transarterial Hepatic Tumor Embolization

PubMed Central

Johnson, Carmen Gacchina; Sharma, Karun V.; Levy, Elliot B.; Woods, David L.; Morris, Aaron H.; Bacher, John D.; Lewis, Andrew L.; Wood, Bradford J.; Dreher, Matthew R.

2015-01-01

Purpose To quantify changes in tumor microvascular (< 1 mm) perfusion relative to commonly used angiographic endpoints. Materials and Methods Rabbit Vx2 liver tumors were embolized with 100–300-µm LC Bead particles to endpoints of substasis or complete stasis (controls were not embolized). Microvascular perfusion was evaluated by delivering two different fluorophore-conjugated perfusion markers (ie, lectins) through the catheter before embolization and 5 min after reaching the desired angiographic endpoint. Tumor microvasculature was labeled with an anti-CD31 antibody and analyzed with fluorescence microscopy for perfusion marker overlap/mismatch. Data were analyzed by analysis of variance and post hoc test (n = 3–5 per group; 18 total). Results Mean microvascular density was 70 vessels/mm2 ± 17 (standard error of the mean), and 81% ± 1 of microvasculature (ie, CD31+ structures) was functionally perfused within viable Vx2 tumor regions. Embolization to the extent of substasis eliminated perfusion in 37% ± 9 of perfused microvessels (P > .05 vs baseline), whereas embolization to the extent of angiographic stasis eliminated perfusion in 56% ± 8 of perfused microvessels. Persistent microvascular perfusion following embolization was predominantly found in the tumor periphery, adjacent to normal tissue. Newly perfused microvasculature was evident following embolization to substasis but not when embolization was performed to complete angiographic stasis. Conclusions Nearly half of tumor microvasculature remained patent despite embolization to complete angiographic stasis. The observed preservation of tumor microvasculature perfusion with angiographic endpoints of substasis and stasis may have implications for tumor response to embolotherapy. PMID:26321051

Numerical Simulation of Thrombotic Occlusion in Tortuous Arterioles

PubMed Central

Feng, Zhi-Gang; Cortina, Miguel; Chesnutt, Jennifer KW; Han, Hai-Chao

2017-01-01

Tortuous microvessels alter blood flow and stimulate thrombosis but the physical mechanisms are poorly understood. Both tortuous microvessels and abnormally large platelets are seen in diabetic patients. Thus, the objective of this study was to determine the physical effects of arteriole tortuosity and platelet size on the microscale processes of thrombotic occlusion in microvessels. A new lattice-Boltzmann method-based discrete element model was developed to simulate the fluid flow field with fluid-platelet coupling, platelet interactions, thrombus formation, and thrombotic occlusion in tortuous arterioles. Our results show that vessel tortuosity creates high shear stress zones that activate platelets and stimulate thrombus formation. The growth rate depends on the level of tortuosity and the pressure and flow boundary conditions. Once thrombi began to form, platelet collisions with thrombi and subsequent activations were more important than tortuosity level. Thrombus growth narrowed the channel and reduced the flow rate. Larger platelet size leads to quicker decrease of flow rate due to larger thrombi that occluded the arteriole. This study elucidated the important roles that tortuosity and platelet size play in thrombus formation and occlusion in arterioles. PMID:29327739

Stromal-dependent tumor promotion by MIF family members.

PubMed

Mitchell, Robert A; Yaddanapudi, Kavitha

2014-12-01

Solid tumors are composed of a heterogeneous population of cells that interact with each other and with soluble and insoluble factors that, when combined, strongly influence the relative proliferation, differentiation, motility, matrix remodeling, metabolism and microvessel density of malignant lesions. One family of soluble factors that is becoming increasingly associated with pro-tumoral phenotypes within tumor microenvironments is that of the migration inhibitory factor family which includes its namesake, MIF, and its only known family member, D-dopachrome tautomerase (D-DT). This review seeks to highlight our current understanding of the relative contributions of a variety of immune and non-immune tumor stromal cell populations and, within those contexts, will summarize the literature associated with MIF and/or D-DT. Copyright © 2014 Elsevier Inc. All rights reserved.

CXC chemokine ligand 4 (CXCL4) is predictor of tumour angiogenic activity and prognostic biomarker in non-small cell lung cancer (NSCLC) patients undergoing surgical treatment.

PubMed

Spaks, Artjoms; Svirina, Darja; Spaka, Irina; Jaunalksne, Inta; Breiva, Donats; Tracums, Ilmars; Krievins, Dainis

2016-07-01

To evaluate the association of CXC chemokine ligand 4 (CXCL4) plasma levels with tumour angiogenesis in non-small cell lung cancer (NSCLC) and to assess association of CXCL4 with clinical outcomes. Fifty patients with early stage NSCLC who underwent pulmonary resection. CXCL4 levels were analysed by ELISA. Angiogenesis was assessed by immunohistochemistry, and microvessel density (MVD) count. There was positive correlation between MVD and CXCL4 levels. Patients with higher CXCL4 levels had worse overall and disease-free survival. Plasma levels of CXCL4 are associated with tumour vascularity. Increased CXCL4 levels in NSCLC patients undergoing treatment may indicate active cancer-induced angiogenesis associated with relapse and worse outcome.

Monitoring of the biological response to murine hindlimb ischemia with 64Cu-labeled vascular endothelial growth factor-121 positron emission tomography.

PubMed

Willmann, Jürgen K; Chen, Kai; Wang, Hui; Paulmurugan, Ramasamy; Rollins, Mark; Cai, Weibo; Wang, David S; Chen, Ian Y; Gheysens, Olivier; Rodriguez-Porcel, Martin; Chen, Xiaoyuan; Gambhir, Sanjiv S

2008-02-19

Vascular endothelial growth factor-121 (VEGF121), an angiogenic protein secreted in response to hypoxic stress, binds to VEGF receptors (VEGFRs) overexpressed on vessels of ischemic tissue. The purpose of this study was to evaluate 64Cu-VEGF121 positron emission tomography for noninvasive spatial, temporal, and quantitative monitoring of VEGFR2 expression in a murine model of hindlimb ischemia with and without treadmill exercise training. 64Cu-labeled VEGF121 and a VEGF mutant were tested for VEGFR2 binding specificity in cell culture. Mice (n=58) underwent unilateral ligation of the femoral artery, and postoperative tissue ischemia was assessed with laser Doppler imaging. Longitudinal VEGFR2 expression in exercised and nonexercised mice was quantified with 64Cu-VEGF121 positron emission tomography at postoperative day 8, 15, 22, and 29 and correlated with postmortem gamma-counting. Hindlimbs were excised for immunohistochemistry, Western blotting, and microvessel density measurements. Compared with the VEGF mutant, VEGF121 showed specific binding to VEGFR2. Perfusion in ischemic hindlimbs fell to 9% of contralateral hindlimb on postoperative day 1 and recovered to 82% on day 29. 64Cu-VEGF121 uptake in ischemic hindlimbs increased significantly (P < 0.001) from a control level of 0.61+/-0.17% ID/g (percentage of injected dose per gram) to 1.62+/-0.35% ID/g at postoperative day 8, gradually decreased over the following 3 weeks (0.59+/-0.14% ID/g at day 29), and correlated with gamma-counting (R2 = 0.99). Compared with nonexercised mice, 64Cu-VEGF121 uptake was increased significantly (P < or = 0.0001) in exercised mice (at day 15, 22, and 29) and correlated with VEGFR2 levels as obtained by Western blotting (R2 = 0.76). Ischemic hindlimb tissue stained positively for VEGFR2. In exercised mice, microvessel density was increased significantly (P<0.001) compared with nonexercised mice. 64Cu-VEGF121 positron emission tomography allows longitudinal spatial and quantitative monitoring of VEGFR2 expression in murine hindlimb ischemia and indirectly visualizes enhanced angiogenesis stimulated by treadmill exercise training.

Combined cetuximab and genistein treatment shows additive anti-cancer effect on oral squamous cell carcinoma.

PubMed

Park, Sung-Jin; Kim, Myung-Jin; Kim, Yu-Kyoung; Kim, Soung-Min; Park, Ju-Yong; Myoung, Hoon

2010-06-01

The purpose of this study was to evaluate the potency of EGFR pathway inhibition achieved by combining cetuximab, an anti-EGFR monoclonal antibody, and genistein, a tyrosine kinase inhibitor, which target extracellular and intracellular domains of the receptor, respectively, in oral squamous cell carcinoma (OSCC) in vitro and in vivo. Two OSCC cell lines, HSC3 and KB, were treated with cetuximab (C, 0-400mug/ml), genistein (G, 0-80muM), or a combination of both at a range of concentrations. Downstream protein expression of EGFR, p-EGFR, and p-Akt were evaluated by Western blot. Cell proliferation and apoptosis indices were calculated to assess anti-cancer effects in vitro. The in vivo effects of cetuximab and genistein on tumor cell growth were examined using an OSCC xenografted nude mouse model and immunohistochemical analyses of proliferation (PCNA) and microvessel density (CD31). Treatment of cells with dual anti-EGFR agents reduced the expressions of p-EGFR, and p-Akt in HSC3 cell line, but there was no significant difference in downregulation between cetuximab alone and in combination with genistein in KB cells. Both HSC3 and KB cells showed a dose-dependent decrease in cell proliferation significantly with single agent treatment and combination (p<0.05). In low concentration, combined cetuximab and genistein therapy resulted in additive growth inhibition and more apoptosis compared to that achieved with single-agent exposure in both cell lines. A combination of cetuximab and genistein significantly inhibited tumor growth and caused a substantial growth delay in in vivo models of both cell lines while each single-agent exposure caused no delay of tumor growth. Immunohistochemical staining with PCNA revealed that the group receiving combined cetuximab and genistein exhibited the lowest number of proliferating cells and microvessel density (p<0.05). Combined therapy with genistein and cetuximab can add the potency of EGFR signaling inhibition. Because not all OSCC cell types appear to respond uniformly, however, selective targeting of distinct molecular pathways is required for effective clinical response. Copyright (c) 2009 Elsevier Ireland Ltd. All rights reserved.

2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-Glucoside Attenuates Ischemia/Reperfusion-Induced Brain Injury in Rats by Promoting Angiogenesis.

PubMed

Mu, Ying; Xu, Zhaohui; Zhou, Xuanxuan; Zhang, Huinan; Yang, Qian; Zhang, Yunlong; Xie, Yanhua; Kang, Juan; Li, Feng; Wang, Siwang

2017-05-01

Cerebral ischemia can cause brain infarcts, which are difficult to recover due to poor angiogenesis. 2,3,5,4'-Tetrahydroxystilbene-2-O- β -D-glucoside is a natural polyphenol, has antioxidant and anti-inflammatory activity, and can protect from ischemic neuronal injury. However, little is known about the effect of 2,3,5,4'-tetrahydroxystilbene-2-O- β -D-glucoside on brain microcirculation after stroke. This study aimed at investigating the influence of 2,3,5,4'-tetrahydroxystilbene-2-O- β -D-glucoside on brain lesions and angiogenesis after stroke. Sprague-Dawley rats were subjected to right middle cerebral artery occlusion and treated with vehicle, nimodipine, or different doses of 2,3,5,4'-tetrahydroxystilbene-2-O- β -D-glucoside daily beginning at 6 h post-middle cerebral artery occlusion for 14 days. The volume of cerebral infarcts, degree of neurological dysfunction, and level of microvessel density were determined longitudinally. The levels of vascular endothelial growth factor, angiopoietin 1, and angiopoietin receptor-2 expression in the brain lesions were characterized by immunohistochemistry and Western blot assays at 14 days post-middle cerebral artery occlusion. We found that 2,3,5,4'-tetrahydroxystilbene-2-O- β -D-glucoside significantly promoted postoperative recovery in rats by minimizing the volume of cerebral infarcts and improving neurological dysfunction in a dose- and time-dependent manner. Additionally, 2,3,5,4'-tetrahydroxystilbene-2-O- β -D-glucoside significantly increased the microvessel density in the brain and upregulated CD31 expression in ischemic penumbra, relative to that in the control. Finally, treatment with 2,3,5,4'-tetrahydroxystilbene-2-O- β -D-glucoside significantly upregulated the relative levels of vascular endothelial growth factor, angiopoietin 1, and angiopoietin receptor-2 expression in the brain lesions of rats. Therefore, these data indicated that 2,3,5,4'-tetrahydroxystilbene-2-O- β -D-glucoside treatment promoted angiogenesis and recovery from ischemia/reperfusion-induced brain injury in rats. Georg Thieme Verlag KG Stuttgart · New York.

Effect of peritoneal dialysis on expression of vascular endothelial growth factor, basic fibroblast growth factor and endostatin of the peritoneum in peritoneal dialysis patients.

PubMed

Gao, Dan; Zhao, Zhan-Zheng; Liang, Xian-Hui; Li, Yan; Cao, Ying; Liu, Zhang-Suo

2011-11-01

The aim of this study is to investigate the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and endostatin (ES) in human peritoneum and investigate the relationship between them and peritoneum neoangiogensis in the patients with uraemia and peritoneal dialysis (PD). Peritoneal biopsies were obtained from normal subjects (n = 8), uraemic predialysis patients (n = 12) and PD patients (n = 10). The mRNA expression of VEGF, bFGF and ES in peritoneal tissues were measured through real-time polymerase chain reaction. The protein expression of VEGF, bFGF and ES in peritoneal tissues were determined through western blot. Microvessel density (MVD) of peritoneal tissue was assessed using immunohistochemistry with CD34 monoclonal antibody. The mRNA and protein of VEGF, bFGF and ES were expressed in all peritoneal samples. Compared with the normal control group, the mRNA and protein expression of VEGF and bFGF in peritoneal tissues were all significantly upregulated in the uraemic predialysis and PD group (all P < 0.05). Compared with the normal control group, the protein expression of ES were significantly upregulated in the uraemic predialysis and PD group (all (P < 0.05), but the mRNA expression of ES did not have obvious differences in the uraemic predialysis and PD group as compared to the normal control group (P > 0.05). MVD of peritoneal tissue were increased in the uraemic predialysis and PD group compared with the normal group (all P < 0.05). A significant positive correlation was found between VEGF mRNA expression and MVD, bFGF mRNA expression and MVD. The mRNA expression of VEGF and bFGF, the protein expression of VEGF, bFGF, and ES and microvessel density (MVD) are increased both in the uraemic predialysis and PD patients. These results show that uraemia circumstances and non-physiological compatibility of peritoneal dialysis solution might increase VEGF, bFGF and ES expression and MVD, which might participate in the increment of the peritoneum neoangiogensis and ultrafiltration failure in PD patients. © 2011 The Authors. Nephrology © 2011 Asian Pacific Society of Nephrology.

The associations between serum VEGF, bFGF and endoglin levels with microvessel density and expression of proangiogenic factors in malignant and benign ovarian tumors.

PubMed

Szubert, Sebastian; Moszynski, Rafal; Michalak, Slawomir; Nowicki, Michal; Sajdak, Stefan; Szpurek, Dariusz

2016-09-01

To investigate whether serum levels of VEGF, bFGF and endoglin correlate with tumor VEGF and bFGF expression or microvessel density (MVD) in ovarian cancer. Forty five patients with epithelial ovarian cancers (EOCs) and 38 patients with benign ovarian tumors (BOTs) were included into the study. Serum levels of VEGF, bFGF and endoglin were assessed using ELISA. The expression of VEGF and bFGF in tumor samples were evaluated using ELISA of supernatants obtained from tumor homogenization. MVD was analyzed using immunohistochemistry with antibodies against CD31, CD34 and CD105. Serum VEGF levels were significantly higher in EOCs than in BOTs (436.6pg/ml [19.67-2860] vs 295.5pg/ml [123-539], P=0.025). Serum endoglin levels were lowered in the group EOCs when compared to BOTs (33,720g/ml [12,220-73,940] vs 42,390pg/ml [19,380-56,910], P=0.015). There were no differences in bFGF levels between studied groups. EOCs have significantly higher CD105 MVD (25 vessels/mm2 [0-57] vs 6 vessels/mm2 [0-70], P<0.001) and tumor VEGF (405.9pg/mg protein [0-3000] vs 2.225 [0-634.7], P<0.001) expression than BOTs, while, bFGF expression was higher in BOTs than in EOCs (2076pg/mg protein [668.1-8718] vs 847.3pg/mg protein [188.9-8333], P=0.003). In patients with EOCs we have observed negative correlation between serum VEGF concentration and its tissue expression (r Spearman=-0.571, P=0.0261), and serum VEGF concentration correlated positively with CD34-MVD (r Spearman=0.545, P=0.0289). In a multiple regression analysis we have observed only the negative correlation between serum VEGF and CD105-MVD (r=-0.5288, P=0.0427). Serum VEGF is a useful marker for prediction of ovarian cancer MVD and tumor VEGF expression. Copyright © 2016 Elsevier Inc. All rights reserved.

The contribution of CXCL12-expressing radial glia cells to neuro-vascular patterning during human cerebral cortex development

PubMed Central

Errede, Mariella; Girolamo, Francesco; Rizzi, Marco; Bertossi, Mirella; Roncali, Luisa; Virgintino, Daniela

2014-01-01

This study was conducted on human developing brain by laser confocal and transmission electron microscopy (TEM) to make a detailed analysis of important features of blood-brain barrier (BBB) microvessels and possible control mechanisms of vessel growth and differentiation during cerebral cortex vascularization. The BBB status of cortex microvessels was examined at a defined stage of cortex development, at the end of neuroblast waves of migration, and before cortex lamination, with BBB-endothelial cell markers, namely tight junction (TJ) proteins (occludin and claudin-5) and influx and efflux transporters (Glut-1 and P-glycoprotein), the latter supporting evidence for functional effectiveness of the fetal BBB. According to the well-known roles of astroglia cells on microvessel growth and differentiation, the early composition of astroglia/endothelial cell relationships was analyzed by detecting the appropriate astroglia, endothelial, and pericyte markers. GFAP, chemokine CXCL12, and connexin 43 (Cx43) were utilized as markers of radial glia cells, CD105 (endoglin) as a marker of angiogenically activated endothelial cells (ECs), and proteoglycan NG2 as a marker of immature pericytes. Immunolabeling for CXCL12 showed the highest level of the ligand in radial glial (RG) fibers in contact with the growing cortex microvessels. These specialized contacts, recognizable on both perforating radial vessels and growing collaterals, appeared as CXCL12-reactive en passant, symmetrical and asymmetrical, vessel-specific RG fiber swellings. At the highest confocal resolution, these RG varicosities showed a CXCL12-reactive dot-like content whose microvesicular nature was confirmed by ultrastructural observations. A further analysis of RG varicosities reveals colocalization of CXCL12 with Cx43, which is possibly implicated in vessel-specific chemokine signaling. PMID:25360079

Reproducibility of Retinal Microvascular Traits Decoded by the Singapore I Vessel Assessment Software Across the Human Age Range.

PubMed

Huang, Qi-Fang; Wei, Fang-Fei; Zhang, Zhen-Yu; Raaijmakers, Anke; Asayama, Kei; Thijs, Lutgarde; Yang, Wen-Yi; Mujaj, Blerim; Allegaert, Karel; Verhamme, Peter; Struijker-Boudier, Harry A J; Li, Yan; Staessen, Jan A

2018-03-10

Retinal microvascular traits predict adverse health outcomes. The Singapore I Vessel Assessment (SIVA) software improved automated postprocessing of retinal photographs. In addition to microvessel caliber, it generates measures of arteriolar and venular geometry. Few studies addressed the reproducibility of SIVA measurements across a wide age range. In the current study, 2 blinded graders read images obtained by nonmydriatic retinal photography twice in 20 11-year-old children, born prematurely (n = 10) or at term (n = 10) and in 60 adults (age range, 18.9-86.1 years). Former preterm compared with term children had lower microvessel diameter and disorganized vessel geometry with no differences in intraobserver and interobserver variability. Among adults, microvessel caliber decreased with age and blood pressure and arteriolar geometry was inversely correlated with female sex and age. Intraobserver differences estimated by the Bland-Altman method did not reach significance for any measurement. Across measurements, median reproducibility (RM) expressed as percent of the average trait value was 8.8% in children (median intraclass correlation coefficient [ICC], 0.94) and 8.0% (0.97) in adults. Likewise, interobserver differences did not reach significance with RM (ICC) of 10.6% (0.85) in children and 10.4% (0.93) in adults. Reproducibility was best for microvessel caliber (intraobserver/interobserver RM, 4.7%/6.0%; ICC, 0.98/0.96), worst for venular geometry (17.0%/18.8%; 0.93/0.84), and intermediate for arteriolar geometry (10.9%/14.9%; 0.95/0.86). SIVA produces repeatable measures of the retinal microvasculature in former preterm and term children and in adults, thereby proving its usability from childhood to old age.

IDH1 mutation is associated with lower expression of VEGF but not microvessel formation in glioblastoma multiforme

PubMed Central

Polívka, Jiří; Pešta, Martin; Pitule, Pavel; Hes, Ondřej; Holubec, Luboš; Polívka, Jiří; Kubíková, Tereza; Tonar, Zbyněk

2018-01-01

Introduction Glioblastoma multiforme (GBM) represents the most malignant primary brain tumor characterized by pathological vascularization. Mutations in isocitrate dehydrogenases 1 and 2 (IDH1 and IDH2) were observed in GBM. We aimed to assess the intra-tumor hypoxia, angiogenesis and microvessel formation in GBM and to find their associations with IDH1 mutation status and patients prognosis. Methods 52 patients with a diagnosis of GBM were included into the study. IDH1 R132H mutation was assessed by RT-PCR from FFPE tumor samples obtained during surgery. The expression of markers of hypoxia (HIF2α), angiogenesis (VEGF), tumor microvascularity (CD31, CD34, vWF, CD105), and proliferation (Ki-67) were assessed immunohistochemically (IHC). IDH1 mutation and IHC markers were correlated with the patient survival. Results 20 from 52 GBM tumor samples comprised IDH1 R132H mutation (38.5%). The majority of mutated tumors were classified as secondary glioblastomas (89.9%). Patients with IDH1 mutated tumors experienced better progression-free survival (P = 0.037) as well as overall survival (P = 0.035) compared with wild type tumors. The significantly lower expression of VEGF was observed in GBM with IDH1 mutation than in wild type tumors (P = 0.01). No such association was found for microvascular markers. The increased expression of newly-formed microvessels (ratio CD105/CD31) in tumor samples was associated with worse patient’s progression-free survival (P = 0.026). Summary No increase in HIF/VEGF-mediated angiogenesis was observed in IDH1-mutated GBM compared with IDH1 wild type tumors. The histological assessment of the portion of newly-formed microvessels in tumor tissue can be used for the prediction of GBM patient’s prognosis. PMID:29662659

Characterization of atrial natriuretic peptide receptors in brain microvessel endothelial cells

NASA Technical Reports Server (NTRS)

Whitson, Peggy A.; Huls, M. H.; Sams, Clarence F.

1989-01-01

In view of the suggestions by Chabrier et al. (1987) and Steardo and Nathanson (1987) that atrial natriuretic peptide (ANP) may play a role in the fluid homeostasis of the brain, the ANP receptors in primary cultures of bovine brain microvessel endothelian cells were quantitated and characterized. Results of partition binding studies and the effect of cGMP additions indicated the presence of at least two types of ANP receptors, with the majority of the receptors being the nonguanylate cyclase coupled receptors. The presence of at least two ANP receptor types suggests an active role for ANP in regulating brain endothelial cell function.

[Oxygen diffusion through the venule walls in the rat cerebral cortex during breathing with pure oxygen].

PubMed

Vovenko, E P; Sokolova, I B; Loshchagin, O V

2002-03-01

Using oxygen microelectrodes, distribution of oxygen tension (pO2) has been studied in venules of the rat brain cortex at normobaric hyperoxia (spontaneous breathing with pure oxygen). It has been shown that inhalation of oxygen results in sharp increase of pO2 in majority of the venules under study. The pO2 distribution along the length of venous microvessels of 7-280 microns in diameter is best approximated by equation: pO2 = 76.44 e-0.0008D, n = 407. The pO2 distribution was characterised by extremely high pO2 values (180-240 mm Hg) in some minute venules. Heterogeneity of pO2 distribution in venous microvessels at hyperoxia was shown to be significantly increased. Profiles of pO2 between neighbouring arterioles and venules were for the first time measured. The data clearly evidenced that O2 diffusional shunting took place between cortical arterioles and venules, provided they were distanced from each other for not over 80-100 microns. Distribution of pO2 in venules has been shown to be dependent on the blood flow in the brain cortical microvessels.

Lymphangiogenesis assessed using three methods is related to tumour grade, breast cancer subtype and expression of basal marker.

PubMed

Niemiec, Joanna; Adamczyk, Agnieszka; Ambicka, Aleksandra; Mucha-Małecka, Anna; Wysocki, Wojciech; Mituś, Jerzy; Ryś, Janusz

2012-11-01

Lymphangiogenesis is a potential indicator of cancer patients' survival. However, there is no standardisation of methodologies applied to the assessment of lymphatic vessel density. In 156 invasive ductal breast cancers (T  1/N+/M0), lymphatic and blood vessels were visualised using podoplanin and CD34, respectively. Based on these markers expression, four parameters were assessed: (i) distribution of podoplanin-stained vessels (DPV) - the percentage of fields with at least one lymphatic vessel (a simple method proposed by us), (ii) lymphatic vessel density (LVD), (iii) LVD to microvessel density ratio (LVD/MVD) and (iv) the expression of podoplanin in cancer-associated fibroblasts. Next, we estimated relations between the above-mentioned parameters and: (i) breast cancer subtype, (ii) tumour grade, and (iii) basal markers expression. We found that intensive lymphangiogenesis, assessed using all studied methods, is positively related to high tumour grade, triple negative or HER2 subtype and expression of basal markers. Whereas, the absence of podoplanin expression in fibroblasts of cancer stroma is related to luminal A subtype, low tumour grade or lack of basal markers expression. Distribution of podoplanin-stained vessels, assessed by a simple method proposed by us (indicating the percentage of fields with at least one lymphatic vessel), might be used instead of the "hot-spot" method.

Vitamin D binding protein-macrophage activating factor (DBP-maf) inhibits angiogenesis and tumor growth in mice.

PubMed

Kisker, Oliver; Onizuka, Shinya; Becker, Christian M; Fannon, Michael; Flynn, Evelyn; D'Amato, Robert; Zetter, Bruce; Folkman, Judah; Ray, Rahul; Swamy, Narasimha; Pirie-Shepherd, Steven

2003-01-01

We have isolated a selectively deglycosylated form of vitamin D binding protein (DBP-maf) generated from systemically available DBP by a human pancreatic cancer cell line. DBP-maf is antiproliferative for endothelial cells and antiangiogenic in the chorioallantoic membrane assay. DBP-maf administered daily was able to potently inhibit the growth of human pancreatic cancer in immune compromised mice (T/C=0.09). At higher doses, DBP-maf caused tumor regression. Histological examination revealed that treated tumors had a higher number of infiltrating macrophages as well as reduced microvessel density, and increased levels of apoptosis relative to untreated tumors. Taken together, these data suggest that DBP-maf is an antiangiogenic molecule that can act directly on endothelium as well as stimulate macrophages to attack both the endothelial and tumor cell compartment of a growing malignancy.

Angiogenesis Markers in Gynecological Tumors and Patents for Anti-Angiogenic Approach: Review.

PubMed

Abdalla, Douglas R; Simoens, Cindy; Bogers, John-Paul; Murta, Eddie F C; Michelin, Marcia A

2015-01-01

The formation of a tumor-associated vascular network is an important step in understanding the stages of tumor progression. This review aims to highlight the main markers of induction, proliferation and inhibition of angiogenesis, as well as the quantification of microvessel density, correlated with preclinical and clinical research in gynecologic cancers and also discussed related patents. Studies show that in the most advanced cases of gynecological cancers, biomarkers such as VEGF (Vascular Endothelial Growth Factor), MMP (Matrix Metalloproteinase), CD105 (Endoglin), TIMP (tissue inhibitors of metalloproteinases) and VASH (Vasohibin) are more expressed compared to healthy individuals. Continuous evaluation of these biomarkers in cancer cases could serve in the future as a basis for development of new therapeutic approaches, leading to a good response to cancer treatment, and thus increase survival of cancer patients.

Contrast-Enhanced Sonography Depicts Spontaneous Ovarian Cancer at Early Stages in a Preclinical Animal Model

PubMed Central

Barua, Animesh; Bitterman, Pincas; Bahr, Janice M.; Basu, Sanjib; Sheiner, Eyal; Bradaric, Michael J.; Hales, Dale B.; Luborsky, Judith L.; Abramowicz, Jacques S.

2011-01-01

Objective Our goal was to examine the feasibility of using laying hens, a preclinical model of human spontaneous ovarian cancer, in determining the kinetics of an ultrasound contrast agent indicative of ovarian tumor-associated neoangiogenesis in early-stage ovarian cancer. Methods Three-year-old White Leghorn laying hens with decreased ovarian function were scanned before and after intravenous injection of a human serum albumin–perflutren contrast agent at a dose of 5 µL/kg body weight. Gray scale morphologic characteristics, Doppler indices, the arrival time, peak intensity, and wash-out of the contrast agent were recorded and archived on still images and video clips. Hens were euthanized thereafter; sonographic predictions were compared at gross examination; and ovarian tissues were collected. Archived clips were analyzed to determine contrast parameters and Doppler intensities of vessels. A time-intensity curve per hen was drawn, and the area under the curve was derived. Tumor types and the density of ovarian microvessels were determined by histologic examination and immunohistochemistry and compared to sonographic predictions. Results The contrast agent significantly (P < .05) enhanced the visualization of microvessels, which was confirmed by immunohistochemistry. Contrast parameters, including the time of wash-out and area under the curve, were significantly different (P < .05) between ovaries of normal hens and hens with ovarian cancer and correctly detected cancer at earlier stages than the time of peak intensity. Conclusions The laying hen may be a useful animal model for determining ovarian tumor-associated vascular kinetics diagnostic of early-stage ovarian cancer using a contrast agent. This model may also be useful for testing the efficacy of different contrast agents in a preclinical setting. PMID:21357555

Luteolin Inhibits Human Prostate Tumor Growth by Suppressing Vascular Endothelial Growth Factor Receptor 2-Mediated Angiogenesis

PubMed Central

Pratheeshkumar, Poyil; Son, Young-Ok; Budhraja, Amit; Wang, Xin; Ding, Songze; Wang, Lei; Hitron, Andrew; Lee, Jeong-Chae; Kim, Donghern; Divya, Sasidharan Padmaja; Chen, Gang; Zhang, Zhuo; Luo, Jia; Shi, Xianglin

2012-01-01

Angiogenesis, the formation of new blood vessels from pre-existing vascular beds, is essential for tumor growth, invasion, and metastasis. Luteolin is a common dietary flavonoid found in fruits and vegetables. We studied the antiangiogenic activity of luteolin using in vitro, ex vivo, and in vivo models. In vitro studies using rat aortic ring assay showed that luteolin at non-toxic concentrations significantly inhibited microvessel sprouting and proliferation, migration, invasion and tube formation of endothelial cells, which are key events in the process of angiogenesis. Luteolin also inhibited ex vivo angiogenesis as revealed by chicken egg chorioallantoic membrane assay (CAM) and matrigel plug assay. Gelatin zymographic analysis demonstrated the inhibitory effect of luteolin on the activation of matrix metalloproteinases MMP-2 and MMP-9. Western blot analysis showed that luteolin suppressed VEGF induced phosphorylation of VEGF receptor 2 and their downstream protein kinases AKT, ERK, mTOR, P70S6K, MMP-2, and MMP-9 in HUVECs. Proinflammatory cytokines such as IL-1β, IL-6, IL-8, and TNF-α level were significantly reduced by the treatment of luteolin in PC-3 cells. Luteolin (10 mg/kg/d) significantly reduced the volume and the weight of solid tumors in prostate xenograft mouse model, indicating that luteolin inhibited tumorigenesis by targeting angiogenesis. CD31 and CD34 immunohistochemical staining further revealed that the microvessel density could be remarkably suppressed by luteolin. Moreover, luteolin reduced cell viability and induced apoptosis in prostate cancer cells, which were correlated with the downregulation of AKT, ERK, mTOR, P70S6K, MMP-2, and MMP-9 expressions. Taken together, our findings demonstrate that luteolin inhibits human prostate tumor growth by suppressing vascular endothelial growth factor receptor 2-mediated angiogenesis. PMID:23300633

Combined Gene Therapy Using AdsVEGFR2 and AdsTie2 With Chemotherapy Reduces the Growth of Human Ovarian Cancer and Formation of Ascites in Mice.

PubMed

Tuppurainen, Laura; Sallinen, Hanna; Karvonen, Anni; Valkonen, Elina; Laakso, Hanne; Liimatainen, Timo; Hytönen, Elisa; Hämäläinen, Kirsi; Kosma, Veli-Matti; Anttila, Maarit; Ylä-Herttuala, Seppo

2017-06-01

Ovarian cancer is highly dependent on tumor microvessels and angiogenesis regulated by vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) and angiopoietins (Ang) and their Tie receptors. We studied the efficacy of adenoviral (Ad) gene therapy with soluble VEGFR2 and Tie2 combined with paclitaxel and carboplatin for the treatment of ovarian cancer. An intraperitoneal human ovarian cancer xenograft model in nude mice (n = 44) was used in this study. Gene therapy was given intravenously when the presence of sizable tumors was confirmed in magnetic resonance imaging. The study groups were as follows: AdCMV as a control (group I), AdCMV with chemotherapy (group II), AdsVEGFR2 and AdsTie2 (group III), and AdsVEGFR2 and AdsTie2 with chemotherapy (group IV). Antitumor effectiveness was assessed by overall tumor growth, ascites, immunohistochemistry, microvessel density, and sequential magnetic resonance imaging analyses. AdsVEGFR2 and AdsTie2 gene therapy (group III) significantly reduced tumor weights as compared with group II (P = 0.007). Accumulation of ascites was significantly reduced when the mice were treated with AdsVEGFR2 and AdsTie2 gene therapy or with combined gene therapy and chemotherapy as compared with controls (P = 0.029 and P = 0.010, respectively). Vascular endothelial growth factor and Ang2 levels in ascites fluid were elevated after the gene therapy. Combined inhibition of VEGF/VEGFR2 and Ang/Tie2 pathways provided efficient therapy for ovarian cancer in mice. In addition, antiangiogenic gene therapy has potential as a treatment for the accumulation of ascites.

Life and death in the microcirculation: a role for angiotensin II

NASA Technical Reports Server (NTRS)

Greene, A. S.; Cowley, A. W. (Principal Investigator)

1998-01-01

OBJECTIVE: Angiotensin II (ANGII) plays a critical role in the maintenance of the microcirculation and in the anatomical loss of microvessels (rarefaction) that occurs in low renin forms of hypertension and in animals fed a high-salt diet. Elevations in sodium intake can trigger a series of hemodynamic and hormonal responses culminating in a substantial rarefaction of small arterioles and capillaries in both normal and reduced renal mass hypertensive rats. METHODS: Immunohistochemistry, Northern blot, and reverse transcription-polymerase chain reaction (RT-PCR) analysis of microdissected blood vessels were used to localize ANGII receptors in the microcirculation. Chronic infusion of ANGII and other physiologic and pharmacologic manipulations of the reninangiotensin system in rats was combined with morphologic and mathematical analysis of the network architecture. RESULTS: We have shown that rarefaction of the microcirculation can cause an increase in total peripheral resistance, reduced tissue perfusion, decreased oxygen delivery, and impaired organ function. Although the mechanisms by which this occurs are not well understood, a number of key observations point to a role for the renin-angiotensin system in this effect. First, ANGII infused systemically at subpressor levels, or locally into the skeletal muscle interstitium, can induce significant microvessel growth. Second, localization of ANGII receptor proteins by immunohistochemistry and Western blotting and RNA localization by RT-PCR confirm the presence of AT1 receptors, which are growth-stimulatory, and AT2 receptors, which are growth-inhibitory in the microcirculation. Third, maintenance of ANGII at normal levels during periods of hypertension or high-salt diet completely eliminates rarefaction. CONCLUSIONS: Taken together, these results support the hypothesis that ANGII acting through AT1- and AT2-receptor mechanisms modulate vessel density during high-salt diet and hypertension.

ABT-510, a modified type 1 repeat peptide of thrombospondin, inhibits malignant glioma growth in vivo by inhibiting angiogenesis.

PubMed

Anderson, Joshua C; Grammer, J Robert; Wang, Wenquan; Nabors, L Burton; Henkin, Jack; Stewart, Jerry E; Gladson, Candece L

2007-03-01

Anti-angiogenic therapies would be particularly beneficial in the treatment of malignant gliomas. Peptides derived from the second type 1 repeat (TSR) of thrombospondin-1 (TSP-1) have been shown to inhibit angiogenesis in non-glioma tumor models and a modified TSR peptide, ABT-510, has now entered into Phase II clinical trials of its efficacy in non-glioma tumors. As microvascular endothelial cells (MvEC) exhibit heterogeneity, we evaluated the ability of the modified TSR peptide (NAcSarGlyValDallolleThrNvalleArgProNHE, ABT-510) to inhibit malignant glioma growth in vivo and to induce apoptosis of brain microvessel endothelial cells (MvEC) propagated in vitro. We found that daily administration of ABT-510 until euthanasia (days 7 to 19), significantly inhibited the growth of human malignant astrocytoma tumors established in the brain of athymic nude mice. The microvessel density was significantly lower and the number of apoptotic MvEC was significantly higher (3-fold) in the tumors of the ABT-510-treated animals. Similar results were found using a model in which the established tumor is an intracerebral malignant glioma propagated in a syngeneic mouse model. ABT-510 treatment of primary human brain MvEC propagated as a monolayer resulted in induction of apoptosis in a dose- and time-dependent manner through a caspase-8-dependent mechanism. It also inhibited tubular morphogenesis of MvEC propagated in collagen gels in a dose- and caspase-8 dependent manner through a mechanism that requires the TSP-1 receptor (CD36) on the MvEC. These findings indicate that ABT-510 should be evaluated as a therapeutic option for patients with malignant glioma.

Effects and mechanism of recombinant human erythropoietin on the growth of human breast cancer MDA-MB-231 cells in nude mice.

PubMed

Jin, Wen; Lin, Zhiwu; Zhang, Xiaorong; Kong, Lingying; Yang, Li

2015-08-01

This study aimed to explore the effects of recombinant human erythropoietin (rhEPO) on the growth of human breast cancer MDA-MB-231 cells in nude mice, and investigate its functions in regulating tumor growth, angiogenesis and apoptosis. A tumor-bearing nude mice model was established by subcutaneous injection of human breast cancer MDA-MB-231 cells. Two weeks later, the mice were randomly divided into four groups (n=6 for each group): negative control group, rhEPO group, EPO antibody group and EPO+EPO antibody group. Drugs were administered to the corresponding mice once every 3 days for five times. The size and weight of tumors were measured after the mice were sacrificed by cervical dislocation. The expression levels of EPO/EPOR, TNF-α, IL-10, and Bcl-2 in the tumor tissues were determined using RT-PCR and Western blot. The microvessel density (MVD) and expression of VEGF in the tumors were detected using immunohistochemistry. TUNEL assay was used to determine apoptosis in tumors. Results show that rhEPO significantly promoted the growth of MDA-MB-231 cells in nude mice (P<0.05). Compared with the negative control group, the expression levels of EPO, EPOR, TNF-α, IL-10, and VEGF, as well as the MVD values, were significantly elevated in the rhEPO group. However, the apoptotic index was significantly reduced (P<0.05). The ability of rhEPO to promote tumor growth may be associated with its functions in promoting microvessel formation and inhibiting tumor cell apoptosis. Copyright © 2015 Elsevier GmbH. All rights reserved.

Pannus inflammation in sacroiliitis following immune pathological injury and radiological structural damage: a study of 193 patients with spondyloarthritis.

PubMed

Wang, Dan Min; Lin, Ling; Peng, Jian Hua; Gong, Yao; Hou, Zhi Duo; Chen, Su Biao; Xiao, Zheng Yu

2018-06-08

The pathogenesis of sacroiliitis is unclear; therefore, we aimed to systematically study the immunopathology of sacroiliitis in patients with axial spondyloarthritis (axSpA), and explore the relationship between pannus formation, inflammation, and the structural damage caused by sacroiliitis. Fine needle aspiration biopsy of the sacroiliac joint (SIJ) was performed in 193 patients with axSpA. Clinical, laboratory, and imaging data were collected at baseline and during the follow up. Immunohistochemistry analysis was performed to detect CD34+ microvessels, CD68+ osteoclasts/macrophages, vascular endothelial growth factor (VEGF), metalloproteinase-3 (MMP-3), tumor necrosis factor-α (TNF-α), and caspase-3. Autopsy subjects were used as controls. In early sacroiliitis (grade 0-1) all pathological features could be observed, with the most common being subchondral pannus formation. Among the 193 patients, 98 were followed up for 1-13 years (mean 3.6 years); 63.3% had radiological progression at the endpoint. Multiple regression analysis showed that cartilage pannus invasion (OR 2.99, P = 0.010) and endochondral ossification (OR 3.97, P = 0.049) at baseline were risk factors for radiological structural damage. Compared to SIJ controls, the subchondral microvessel density, number of CD68+ multinuclear osteoclasts, and the levels of VEGF, caspase-3, MMP-3, and TNF-α expressed at the interface of the bone and cartilage were significantly higher in patients with sacroiliitis. Subchondral fibrovascular tissue formation is the most important pathological feature in early sacroiliitis. The existence of cartilage pannus invasion or endochondral ossification at baseline can predict radiological structural damage during the follow up.

Anti-sphingosine-1-phosphate monoclonal antibodies inhibit angiogenesis and sub-retinal fibrosis in a murine model of laser-induced choroidal neovascularization

PubMed Central

Caballero, Sergio; Swaney, James; Moreno, Kelli; Afzal, Aqeela; Kielczewski, Jennifer; Stoller, Glenn; Cavalli, Amy; Garland, William; Hansen, Geneviève; Sabbadini, Roger; Grant, Maria B.

2013-01-01

The efficacy of novel monoclonal antibodies that neutralize the pro-angiogenic mediator, sphingosine-1-phosphate (S1P), were tested using in vitro and in vivo angiogenesis models, including choroidal neovascularization (CNV) induced by laser disruption of Bruch’s membrane. S1P receptor levels in human brain choroid plexus endothelial cells (CPEC), human lung microvascular endothelial cells, human retinal vascular endothelial cells, and circulating endothelial progenitor cells were examined by semi-quantitative PCR. The ability of murine or humanized anti-S1P monoclonal antibodies (mAbs) to inhibit S1P-mediated microvessel tube formation by CPEC on Matrigel was evaluated and capillary density in subcutaneous growth factor-loaded Matrigel plugs was determined following anti-S1P treatment. S1P promoted in vitro capillary tube formation in CPEC consistent with the presence of cognate S1P1–5 receptor expression by these cells and the S1P antibody induced a dose-dependent reduction in microvessel tube formation. In a murine model of laser-induced rupture of Bruch’s membrane, S1P was detected in posterior cups of mice receiving laser injury, but not in uninjured controls. Intravitreous injection of anti-S1P mAbs dramatically inhibited CNV formation and sub-retinal collagen deposition in all treatment groups (p < 0.05 compared to controls), thereby identifying S1P as a previously unrecognized mediator of angiogenesis and subretinal fibrosis in this model. These findings suggest that neutralizing S1P with anti-S1P mAbs may be a novel method of treating patients with exudative age-related macular degeneration by reducing angiogenesis and sub-retinal fibrosis, which are responsible for visual acuity loss in this disease. PMID:18723015

Correlation between spontaneous apoptosis and the expression of angiogenic factors in advanced gastric adenocarcinoma.

PubMed

Ikeguchi, M; Cai, J; Fukuda, K; Oka, S; Katano, K; Tsujitani, S; Maeta, M; Kaibara, N

2001-06-01

The aim of this study was to investigate whether angiogenic factors influence the occurrence of spontaneous apoptosis in advanced gastric cancer. The apoptotic indices (AIs) of 97 tumors from 97 patients with advanced gastric cancer (pT3, pN0, pM0, Stage II) were analyzed by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate biotin nick end labeling (TUNEL) method. Intratumoral microvessel densities (IMVDs) of tumors stained with anti-CD34 monoclonal antibody were quantified under x 200 magnification using computer-assisted image analysis. The expressions of angiogenic factors, such as vascular endothelial growth factor (VEGF), thymidine phosphorylase (dThdPase), transforming growth factor-alpha (TGF-alpha), and p53 were analyzed immunohistochemically and compared with IMVDs and AIs. The mean IMVD of the 97 tumors was 365/mm2 (range 147-990/mm2). The mean AI of tumors was 2.1% (range 0-11.3%). A significant inverse correlation between the AIs and the IMVDs was shown (p = -0.278, P = 0.0064). The mean IMVDs of tumors with high expressions of dThdPase, TGF-alpha, or p53 were significantly higher than those of tumors with low expressions of these factors. The mean AI of tumors with high expressions of dThdPase was significantly lower than that of tumors with low expressions of dThdPase (P = 0.023). However, no significant correlations were detected between AIs and the expression levels of VEGF, TGF-alpha, or p53. In gastric cancer, dThdPase may play an important role in tumor progression by increasing microvessels and by suppressing apoptosis of cancer cells.

The free-radical scavenger edaravone accelerates thrombolysis with alteplase in an experimental thrombosis model.

PubMed

Yamashita, Tsutomu; Sato, Takumi; Sakamoto, Kumi; Ishii, Hiromitsu; Yamamoto, Junichiro

2015-06-01

Reperfusion injury after thrombolytic therapy can have adverse neurologic effects. The free-radical scavenger edaravone is used in combination with the recombinant tissue plasminogen activator alteplase to treat acute ischemic stroke. However, basic investigations of this combination use remain inadequate. Here, we used an in vivo model to investigate the effects of edaravone on alteplase-induced thrombolysis. Thrombolysis was evaluated by using a He-Ne-laser-induced thrombosis model in rat mesenteric microvessels. Changes in thrombus volume were analyzed with the image analysis software Image-Pro Plus (Media Cybernetics, USA). There were three experimental groups (placebo, alteplase 0.6 mg/kg, alteplase 0.6 mg/kg + edaravone 10.5 mg/kg). Sequential changes (0 to 60 min) in thrombus volume were compared by using a relative optical density method that we had used previously. In the placebo group, the thrombus volume at 60 min, reflecting the extent of thrombolysis, was 97.2% ± 5.7% of the initial value. In the alteplase group, thrombus volume decreased to 70.7% ± 4.1% (P<0.01) after 20 min and 14.2% ± 6.6% after 60 min. In the alteplase+edaravone group, thrombus volume decreased to 66.9% ± 7.2% (P<0.001) after 10 min and 10.9% ± 2.3% after 60 min. These results support the hypothesis that edaravone accelerates thrombolysis by alteplase. Copyright © 2015 Elsevier Ltd. All rights reserved.

BCL2 expression in CD105 positive neoangiogenic cells and tumor progression in angioimmunoblastic T-cell lymphoma.

PubMed

Ratajczak, Philippe; Leboeuf, Christophe; Wang, Li; Brière, Josette; Loisel-Ferreira, Irmine; Thiéblemont, Catherine; Zhao, Wei-Li; Janin, Anne

2012-06-01

The angiogenic microenvironment has been known to be a component of angioimmunoblastic T-cell lymphoma since its initial characterization. We have shown that angioimmunoblastic T-cell lymphoma endothelial cells produce vascular endothelial growth factor-A (VEGFA), and participate in lymphoma progression. In squamous cell carcinoma, endothelial BCL2 expression induces a crosstalk with tumor cells through VEGFA, a major mediator of tumoral angiogenesis. In the present study, we analyzed BCL2 and VEGFA in 30 angioimmunoblastic T-cell lymphomas, using triple immunofluorescence to identify protein coexpression in well-characterized lymphoma cells and microenvironment neoangiogenic endothelial cells. Using quantitative real-time PCR, we assessed mRNA expression levels in laser-microdissected endothelial and lymphoma cells. In lymphoma cells, as in endothelial cells, BCL2 and VEGFA proteins were coexpressed. BCL2 was expressed only in neoangiogenic CD34(+)CD105(+) endothelial cells. In laser-microdissected cells, mRNA studies showed a significant relationship between BCL2 and VEGFA levels in CD34(+) endothelial cells, but not in CD3(+)CD10(+)lymphoma cells, or in CD34(+) endothelial cells from lymph node hyperplasia. Further study showed that, in AITL, BCL2 mRNA levels in CD34(+)CD105(+) neoangiogenic endothelial cells also correlated with microvessel density, International Prognostic Index, Ann Arbor stage, bone marrow involvement and elevated LDH. BCL2 expression by CD105(+) neoangiogenic endothelial cells is related to tumor progression in angioimmunoblastic T-cell lymphoma.

Numerical simulation of heat transfer in blood flow altered by electroosmosis through tapered micro-vessels.

PubMed

Prakash, J; Ramesh, K; Tripathi, D; Kumar, R

2018-07-01

A numerical simulation is presented to study the heat and flow characteristics of blood flow altered by electroosmosis through the tapered micro-vessels. Blood is assumed as non-Newtonian (micropolar) nanofluids. The flow regime is considered as asymmetric diverging (tapered) microchannel for more realistic micro-vessels which is produced by choosing the peristaltic wave train on the walls to have different amplitudes and phase. The Rosseland approximation is employed to model the radiation heat transfer and temperatures of the walls are presumed constants. The mathematical formulation of the present problem is simplified under the long-wavelength, low-Reynolds number and Debye-Hückel linearization approximations. The influence of various dominant physical parameters are discussed for axial velocity, microrotation distribution, thermal temperature distribution and nanoparticle volume fraction field. However, our foremost emphasis is to determine the effects of thermal radiation and coupling number on the axial velocity and microrotation distribution beneath electroosmotic environment. This analysis places a significant observation on the thermal radiation and coupling number which plays an influential role in hearten fluid velocity. This study is encouraged by exploring the nanofluid-dynamics in peristaltic transport as symbolized by heat transport in biological flows and also in novel pharmacodynamics pumps and gastro-intestinal motility enhancement. Copyright © 2018 Elsevier Inc. All rights reserved.

Microvascular fractal dimension predicts prognosis and response to chemotherapy in glioblastoma: an automatic image analysis study.

PubMed

Chen, Cong; He, Zhi-Cheng; Shi, Yu; Zhou, Wenchao; Zhang, Xia; Xiao, Hua-Liang; Wu, Hai-Bo; Yao, Xiao-Hong; Luo, Wan-Chun; Cui, You-Hong; Bao, Shideng; Kung, Hsiang-Fu; Bian, Xiu-Wu; Ping, Yi-Fang

2018-05-15

The microvascular profile has been included in the WHO glioma grading criteria. Nevertheless, microvessels in gliomas of the same WHO grade, e.g., WHO IV glioblastoma (GBM), exhibit heterogeneous and polymorphic morphology, whose possible clinical significance remains to be determined. In this study, we employed a fractal geometry-derived parameter, microvascular fractal dimension (mvFD), to quantify microvessel complexity and developed a home-made macro in Image J software to automatically determine mvFD from the microvessel-stained immunohistochemical images of GBM. We found that mvFD effectively quantified the morphological complexity of GBM microvasculature. Furthermore, high mvFD favored the survival of GBM patients as an independent prognostic indicator and predicted a better response to chemotherapy of GBM patients. When investigating the underlying relations between mvFD and tumor growth by deploying Ki67/mvFD as an index for microvasculature-normalized tumor proliferation, we discovered an inverse correlation between mvFD and Ki67/mvFD. Furthermore, mvFD inversely correlated with the expressions of a glycolytic marker, LDHA, which indicated poor prognosis of GBM patients. Conclusively, we developed an automatic approach for mvFD measurement, and demonstrated that mvFD could predict the prognosis and response to chemotherapy of GBM patients.

Photo-mediated ultrasound therapy (PUT): a novel method of selectively treating neovascularization (Conference Presentation)

NASA Astrophysics Data System (ADS)

Zhang, Haonan; Hu, Zi Zhong; Li, Jia; Mordovanakis, Aghapi G.; Yang, Xinmai; Paulus, Yannis M.; Wang, Xueding

2017-02-01

Retinal and choroidal neovascularization play a pivotal role in the leading causes of blindness including macular degeneration and diabetic retinopathy (DR). Current therapy by focal laser photocoagulation can damage the normal surrounding cells, such as the photoreceptor inner and outer segments which are adjacent to the retinal pigment epithelium (RPE), due to the use of high laser energy and millisecond pulse duration. Therapies with pharmaceutical agents involve systemic administration of drugs, which can cause adverse effects and patients may become drug-resistant. We have developed a noninvasive photo-mediated ultrasound therapy (PUT) technique as a localized antivascular method, and applied it to remove micro blood vessels in the retina. PUT takes advantage of the high native optical contrast among biological tissues, and has the unique capability to self-target microvessels without causing unwanted damages to the surrounding tissues. This technique promotes cavitation activity in blood vessels by synergistically applying nanosecond laser pulses and ultrasound bursts. Through the interaction between cavitation and blood vessel wall, blood clots in microvessels and vasoconstriction can be induced. As a result, microvessels can be occluded. In comparison with other techniques that involves cavitation, both laser and ultrasound energy needed in PUT is significantly lower, and hence improves the safety in therapy.

Numerical investigation of oxygen transport by hemoglobin-based carriers through microvessels.

PubMed

Hyakutake, Toru; Kishimoto, Takumi

2017-12-01

The small size of hemoglobin-based oxygen carriers (HBOCs) may expand the realm of new treatment possibilities for various circulatory diseases. The parametric evaluation of HBOC performance for oxygen transport within tissue is essential for effectively characterizing its performance for each circulatory disease assessed. Thus, the overarching objective of this present study was to numerically investigate the reaction-diffusion phenomenon of oxygenated HBOCs and oxygen on tissues through microvessels. We considered dissociation rate coefficients, oxygen affinity, and diffusion coefficients due to Brownian motion as the biophysical parameters for estimating HBOC performance for oxygen transport. A two-dimensional computational domain, including vessel and tissue regions, was, therefore, accordingly assumed. It was observed that HBOC flows in a microvessel with a diameter of 25 μm and a length of 1 mm, and that the dissociated oxygen diffuses to the tissue region. The results indicated that oxyhemoglobin saturation and partial oxygen tension in a downstream region changed according to each biophysical parameter of HBOC. Moreover, the change in oxygen consumption rate in the tissue region had considerable influence on the oxyhemoglobin saturation level within the vessel. Comparison between simulation results and existing in vitro experimental data of actual HBOCs and RBC showed qualitatively good agreement. These results provide important information for the effective design of robust HBOCs in future.

Engineering of functional, perfusable 3D microvascular networks on a chip.

PubMed

Kim, Sudong; Lee, Hyunjae; Chung, Minhwan; Jeon, Noo Li

2013-04-21

Generating perfusable 3D microvessels in vitro is an important goal for tissue engineering, as well as for reliable modelling of blood vessel function. To date, in vitro blood vessel models have not been able to accurately reproduce the dynamics and responses of endothelial cells to grow perfusable and functional 3D vascular networks. Here we describe a microfluidic-based platform whereby we model natural cellular programs found during normal development and angiogenesis to form perfusable networks of intact 3D microvessels as well as tumor vasculatures based on the spatially controlled co-culture of endothelial cells with stromal fibroblasts, pericytes or cancer cells. The microvessels possess the characteristic morphological and biochemical markers of in vivo blood vessels, and exhibit strong barrier function and long-term stability. An open, unobstructed microvasculature allows the delivery of nutrients, chemical compounds, biomolecules and cell suspensions, as well as flow-induced mechanical stimuli into the luminal space of the endothelium, and exhibits faithful responses to physiological shear stress as demonstrated by cytoskeleton rearrangement and increased nitric oxide synthesis. This simple and versatile platform provides a wide range of applications in vascular physiology studies as well as in developing vascularized organ-on-a-chip and human disease models for pharmaceutical screening.

Pathological significance and prognostic roles of densities of CD57+ cells, CD68+ cells, and mast cells, and their ratios in clear cell renal cell carcinoma.

PubMed

Nakanishi, Hiromi; Miyata, Yasuyoshi; Mochizuki, Yasushi; Yasuda, Takuji; Nakamura, Yuichiro; Araki, Kyohei; Sagara, Yuji; Matsuo, Tomohiro; Ohba, Kojiro; Sakai, Hideki

2018-05-19

The immune system is closely associated with malignant behavior in renal cell carcinoma (RCC). Therefore, understanding the pathological roles of immune cells in tumor stroma is essential to discuss the pathological characteristics of RCC. In this study, the clinical significance of densities of CD57+ cells, CD68+ cells, and mast cells, and their ratios were investigated in patients with clear cell RCC. The densities of CD57+, CD68+, and mast cells were evaluated by immunohistochemical techniques in 179 patients. Proliferation index (PI), apoptotic index (AI), and microvessel density (MVD) were evaluated by using anti-Ki-67, anti-cleaved caspase-3, and anti-CD31 antibodies, respectively. The density of CD57+ cell was negatively correlated with grade, pT stage, and metastasis, although densities of CD68+ cell and mast cell were positively correlated. Ratios of CD68+ cell/CD57+ cell and mast cell/CD57+ cell were significantly correlated with grade, pT stage, and metastasis. Survival analyses showed that the CD68+ cell/CD57+ cell ratio was a significant predictor for cause-specific survival by multi-variate analyses (hazard ratio=1.41, 95% confidential interval=1.03-1.93, P=.031), and was significantly correlated with PI, AI, and MVD (r=.47; P <. 001, r=-.31, P<.001, and r=.40, P<.001, respectively). In conclusion, CD57+ cell, CD68+ cell, and mast cell played important roles in malignancy in clear cell RCC. The CD68+ cell/CD57+ cell ratio was strongly correlated with pathological features and prognosis in these patients because this ratio reflected the status of cancer cell proliferation, apoptosis, and angiogenesis. Copyright © 2018. Published by Elsevier Inc.

Functional acetylcholine muscarinic receptor subtypes in human brain microcirculation: identification and cellular localization.

PubMed

Elhusseiny, A; Cohen, Z; Olivier, A; Stanimirović, D B; Hamel, E

1999-07-01

Acetylcholine is an important regulator of local cerebral blood flow. There is, however, limited information available on the possible sites of action of this neurotransmitter on brain intraparenchymal microvessels. In this study, a combination of molecular and functional approaches was used to identify which of the five muscarinic acetylcholine receptors (mAChR) are present in human brain microvessels and their intimately associated astroglial cells. Microvessel and capillary fractions isolated from human cerebral cortex were found by reverse transcriptase-polymerase chain reaction to express m2, m3, and, occasionally, m1 and m5 receptor subtypes. To localize these receptors to a specific cellular compartment of the vessel wall, cultures of human brain microvascular endothelial and smooth muscle cells were used, together with cultured human brain astrocytes. Endothelial cells invariably expressed m2 and m5 receptors, and occasionally the m1 receptor; smooth muscle cells exhibited messages for all except the m4 mAChR subtypes, whereas messages for all five muscarinic receptors were identified in astrocytes. In all three cell types studied, acetylcholine induced a pirenzepine-sensitive increase (62% to 176%, P<0.05 to 0.01) in inositol trisphosphate, suggesting functional coupling of m1, m3, or m5 mAChR to a phospholipase C signaling cascade. Similarly, coupling of m2 or m4 mAChR to adenylate cyclase inhibition in endothelial cells and astrocytes, but not in smooth muscle cells, was demonstrated by the ability of carbachol to significantly reduce (44% to 50%, P<0.05 to 0.01) the forskolin-stimulated increase in cAMP levels. This effect was reversed by the mAChR antagonist AFDX 384. The results indicate that microvessels are able to respond to neurally released acetylcholine and that mAChR, distributed in different vascular and astroglial compartments, could regulate cortical perfusion and, possibly, blood-brain barrier permeability, functions that could become jeopardized in neurodegenerative disorders such as Alzheimer's disease.

Enhancement of P2X(7)-induced pore formation and apoptosis: an early effect of diabetes on the retinal microvasculature.

PubMed

Sugiyama, Tetsuya; Kobayashi, Masato; Kawamura, Hajime; Li, Qing; Puro, Donald G; Kobayshi, Masato

2004-03-01

A sight-threatening complication of diabetes is cell death in retinal capillaries. Currently, the mechanisms responsible for this classic manifestation of diabetic retinopathy remain uncertain. The hypothesis for the current study is that diabetes increases the vulnerability of retinal microvessels to the potentially lethal consequences of having their P2X(7) purinoceptors activated. A pathophysiological role is suspected for these receptor-operated channels because, in addition to transducing retinovascular responses to extracellular adenosine triphosphate (ATP), the sustained opening of these channels can induce the formation of large transmembrane pores. In pericyte-containing retinal microvessels that were freshly isolated from nondiabetic and streptozotocin-injected rats, cells with pores were identified by the uptake of YO-PRO-1. Cell viability was assayed by trypan blue dye exclusion, and cleaved caspase-3 immunoreactivity, TUNEL positivity, and nuclear morphology were used to detect apoptotic cells. Patch-clamp recordings assessed electrophysiological parameters. Activation of P2X(7) receptors caused large pores to form and apoptosis to occur in retinal capillaries of nondiabetic and diabetic rats. Of importance to diabetes, the agonist concentration needed to open pores and trigger apoptosis decreased markedly soon after the onset of streptozotocin-induced hyperglycemia. However, despite this increased sensitivity, diabetes minimally affected the P2X(7)-induced ionic currents. Thus, rather than upregulate the number of functional P2X(7) receptor/channels, diabetes appears to facilitate the channel-to-pore transition that occurs during activation of these purinoceptors. In this way, normally nonlethal concentrations of P2X(7) ligands may trigger apoptosis in microvessels of the diabetic retina. A diabetes-induced increase in the vulnerability of retinal microvessels to the lethal effect of P2X(7) receptor activation may be a previously unrecognized mechanism by which diabetic retinopathy progresses.

Increased pulmonary vascular contraction to serotonin after cardiopulmonary bypass: role of cyclooxygenase.

PubMed

Sato, K; Li, J; Metais, C; Bianchi, C; Sellke, F

2000-05-15

Pulmonary vascular resistance is frequently elevated after cardiopulmonary bypass (CPB). We examined if altered pulmonary microvascular reactivity to serotonin (5-HT) is due to altered expression of isoforms of nitric oxide synthase (NOS) or cyclooxygenase (COX). Pigs (n = 8) were heparinized and placed on total CPB for 90 min and then perfused off CPB for 90 min. Noninstrumented pigs (n = 6) served as controls for vascular studies. Relaxation responses (% of precontraction) of microvessels (60-150 microm in diameter) were examined in vitro in a pressurized (20 mm Hg) no-flow state with video microscopic imaging. Expression of eNOS, iNOS, and inducible (COX-2) and constitutive (COX-1) cyclooxygenase was examined with Western blotting and reverse transcription polymerase chain reaction. Pulmonary vascular resistance (PVR) increased from 316 +/- 39 mm Hg x s/cm(5) at baseline to 495 +/- 53 at 60 min and 565 +/- 62 at 90 min after termination of CPB. 5-HT elicited a relaxation response (46.8 +/- 11. 8%) in precontracted control microvessels. This response was not affected by the NOS inhibitor N(G)-nitro-l-arginine. After CPB, pulmonary microvessels contracted significantly to 5-HT (-29 +/- 27%, P < 0.05 vs control). This response was partially inhibited (7 +/- 20%, P = 0.06) in the presence of the COX-2 inhibitor NS398, but was unaffected by the thromboxane synthase inhibitor U63557A (-20 +/- 19%). Expression of iNOS or COX-1 was not changed after CPB. Protein and mRNA expressions of COX-2 both increased significantly after CPB, while that of eNOS decreased by approximately 50%. PVR increased after CPB. This was associated with a hypercontractile response of isolated pulmonary microvessels to 5-HT that was in part mediated by the release of prostaglandins (but not thromboxane) and associated with increased expression of COX-2 and with decreased expression of eNOS. Copyright 2000 Academic Press.

Association of high microvessel αvβ3 and low PTEN with poor outcome in stage 3 neuroblastoma: rationale for using first in class dual PI3K/BRD4 inhibitor, SF1126

PubMed Central

Singh, Alok R.; Joshi, Shweta; Vega, Francisco M.; Guo, Pinzheng; Xu, Jingying; Groshen, Susan; Ye, Wei; Millard, Melissa; Campan, Mihaela; Morales, Guillermo; Garlich, Joseph R.; Laird, Peter W.; Seeger, Robert C.; Shimada, Hiroyuki

2017-01-01

Neuroblastoma (NB) is the most common extracranial solid tumor in children. Our previous studies showed that the angiogenic integrin αvβ3 was increased in high-risk metastatic (stage 4) NB compared with localized neuroblastomas. Herein, we show that integrin αvβ3 was expressed on 68% of microvessels in MYCN-amplified stage 3 neuroblastomas, but only on 34% (means) in MYCN-non-amplified tumors (p < 0.001; n = 54). PTEN, a tumor suppressor involved in αvβ3 signaling, was expressed in neuroblastomas either diffusely, focally or not at all (immunohistochemistry). Integrin αvβ3 was expressed on 60% of tumor microvessels when PTEN was negative or focal, as compared to 32% of microvessels in tumors with diffuse PTEN expression (p < 0.001). In a MYCN transgenic mouse model, loss of one allele of PTEN promoted tumor growth, illustrating the potential role of PTEN in neuroblastoma pathogenesis. Interestingly, we report the novel dual PI-3K/BRD4 activity of SF1126 (originally developed as an RGD-conjugated pan PI3K inhibitor). SF1126 inhibits BRD4 bromodomain binding to acetylated lysine residues with histone H3 as well as PI3K activity in the MYCN amplified neuroblastoma cell line IMR-32. Moreover, SF1126 suppressed MYCN expression and MYCN associated transcriptional activity in IMR-32 and CHLA136, resulting in overall decrease in neuroblastoma cell viability. Finally, treatment of neuroblastoma tumors with SF1126 inhibited neuroblastoma growth in vivo. These data suggest integrin αvβ3, MYCN/BRD4 and PTEN/PI3K/AKT signaling as biomarkers and hence therapeutic targets in neuroblastoma and support testing of the RGD integrin αvβ3-targeted PI-3K/BRD4 inhibitor, SF1126 as a therapeutic strategy in this specific subgroup of high risk neuroblastoma. PMID:28881723

Quantitative targeted absolute proteomic analysis of transporters, receptors and junction proteins for validation of human cerebral microvascular endothelial cell line hCMEC/D3 as a human blood-brain barrier model.

PubMed

Ohtsuki, Sumio; Ikeda, Chiemi; Uchida, Yasuo; Sakamoto, Yumi; Miller, Florence; Glacial, Fabienne; Decleves, Xavier; Scherrmann, Jean-Michel; Couraud, Pierre-Olivier; Kubo, Yoshiyuki; Tachikawa, Masanori; Terasaki, Tetsuya

2013-01-07

Human cerebral microvascular endothelial cell line hCMEC/D3 is an established model of the human blood-brain barrier (BBB). The purpose of the present study was to determine, by means of quantitative targeted absolute proteomics, the protein expression levels in hCMEC/D3 cells of multiple transporters, receptors and junction proteins for comparison with our previously reported findings in isolated human brain microvessels. Among 91 target molecules, 12 transporters, 2 receptors, 1 junction protein and 1 membrane marker were present at quantifiable levels in plasma membrane fraction of hCMEC/D3 cells. ABCA2, MDR1, MRP4, BCRP, GLUT1, 4F2hc, MCT1, ENT1, transferrin and insulin receptors and claudin-5 were detected in both hCMEC/D3 cells and human brain microvessels. After normalization based on Na(+)/K(+) ATPase expression, the differences in protein expression levels between hCMEC/D3 cells and human brain microvessels were within 4-fold for these proteins, with the exceptions of ENT1, transferrin receptor and claudin-5. ABCA8, LAT1, LRP1 and γ-GTP were below the limit of quantification in the cells, but were found in human brain microvessels. ABCA3, ABCA6, MRP1 and ATA1 were found only in hCMEC/D3 cells. Furthermore, compared with human umbilical vein endothelial cells (HUVECs) as reference nonbrain endothelial cells, MDR1 was found only in hCMEC/D3 cells, and GLUT1 expression was 15-fold higher in hCMEC/D3 cells than in HUVECs. In conclusion, this is the first study to examine the suitability and limitations of the hCMEC/D3 cell line as a BBB functional model in terms of quantitative expression levels of transporters, receptors and tight junction proteins.

Vitamin D Binding Protein-Macrophage Activating Factor (DBP-maf) Inhibits Angiogenesis and Tumor Growth in Mice1

PubMed Central

Kisker, Oliver; Onizuka, Shinya; Becker, Christian M; Fannon, Michael; Flynn, Evelyn; D'Amato, Robert; Zetter, Bruce; Folkman, Judah; Ray, Rahul; Swamy, Narasimha; Pirie-Shepherd, Steven

2003-01-01

Abstract We have isolated a selectively deglycosylated form of vitamin D binding protein (DBP-maf) generated from systemically available DBP by a human pancreatic cancer cell line. DBP-maf is antiproliferative for endothelial cells and antiangiogenic in the chorioallantoic membrane assay. DBP-maf administered daily was able to potently inhibit the growth of human pancreatic cancer in immune compromised mice (T/C=0.09). At higher doses, DBP-maf caused tumor regression. Histological examination revealed that treated tumors had a higher number of infiltrating macrophages as well as reduced microvessel density, and increased levels of apoptosis relative to untreated tumors. Taken together, these data suggest that DBP-maf is an antiangiogenic molecule that can act directly on endothelium as well as stimulate macrophages to attack both the endothelial and tumor cell compartment of a growing malignancy. PMID:12659668

The Characteristics of Incidental Pituitary Microadenomas in 120 Korean Forensic Autopsy Cases

PubMed Central

Kim, Jang-Hee; Seo, Jung-Seok; Lee, Bong-Woo; Lee, Sang-Young; Jeon, Seok-Hoon

2007-01-01

To investigate the characteristics of incidental pituitary microadenomas, we examined 120 pituitary glands from Korean forensic autopsy cases, from which eight tumors were identified (incidence 6.7%). The average age of the affected subjects was 50 yr (range: 33-96 yr) with a female predominance. The maximum diameters of the tumors ranged from 0.4 to 5.4 mm (mean: 2.8 mm). Immunohistochemical analysis of pituitary hormones revealed three growth hormone-secreting adenomas, one prolactin-producing adenoma, one gonadotropin-producing adenoma, one plurihormonal adenoma, and two null cell adenomas. MIB-1 staining for Ki-67 antigen showed no positive expression. The microvessel density (MVD) of the pituitary microadenomas ranged from 2.3 to 11.6% (mean: 5.3%) and was significantly lower than that of nonneoplastic pituitary glands (11.9-20.1%, mean: 14.8%). Our study provides reference data on incidental pituitary microadenomas in the Korean population. PMID:17923757

Angiogenesis in the Progression of Breast Ductal Proliferations

PubMed Central

Carpenter, Philip M.; Chen, Wen-Pin; Mendez, Aaron; McLaren, Christine E.; Su, Min-Ying

2013-01-01

Angiogenesis, the formation of blood vessels, is necessary for a tumor to grow, but when angiogenesis first appears in the progression of breast ductal carcinomas is unknown. To determine when this occurs, the authors examined microvessel density (MVD) by CD31 and CD105 immunostaining in normal ducts, 32 cases of usual hyperplasia, 19 cases of atypical hyperplasia, and 29 cases of ductal carcinoma in situ (DCIS). Simple hyperplasia had a 22-fold greater MVD than normal ducts (P < .0001). An increase during the progression of ductal changes was highly significant (P < .0001). To determine a possible mechanism, immunohistochemistry for vascular endothelial growth factor (VEGF) was evaluated. VEGF staining intensity of ductal epithelium increased during the progression from normal to hyperplastic to DCIS. This study shows that the first significant increase in angiogenesis occurs very early in the evolution of ductal proliferations as ductal cells become hyperplastic. PMID:19403546

[Effects of cuttlefish bone-bone morphogenetic protein composite material on osteogenesis and revascularization of bone defect in rats].

PubMed

Liu, Yuan; Yu, Jiang; Bai, Jie; Gu, Jin-song; Cai, Bin; Zhou, Xia

2013-12-01

To study the effects of cuttlefish bone-bone morphogenetic protein (BMP) composite material on osteogenesis and revascularization of bone defect in rats. The cuttlefish bone was formed into cylinder with the diameter of about 5 mm and height of about 2 mm after the shell was removed, and then it was soaked in the recombinant human BMP 2 to make a cuttlefish bone-BMP (CBB) composite material. Thirty SD rats, with a defect of skull in every rat, were divided into the CBB and pure cuttlefish bone (PCB) groups according to the random number table, with 15 rats in each group. The rats in the group CBB and group PCB were transplanted with the corresponding material to repair the skull defect. At post transplantation week (PTW) 4, 6, and 8, 5 rats from every group were sacrificed by exsanguination, and ink perfusion was performed. One day later, all the transplants and part of the skull surrounding the defect were harvested, and general observation was conducted at the same time. The specimens were paraffin sectioned for HE staining and Masson staining. The area of microvessel and the area of newborn bone were observed and analyzed through histopathological techniques and image collection system. Data were processed with the analysis of variance of factorial design and LSD test. The correlation between the area of microvessel and the area of newborn bone of the group CBB was analyzed with Pearson correlation analysis. (1) The general observation of the transplant region showed that the transplants were encapsulated by a capsule of fibrous connective tissue. The texture of capsule was soft and relatively thick at PTW 4. The texture was tenacious and thin, but rather compact at PTW 6 and 8. The transplants became gelatinous at PTW 4, and similar to the cartilage tissue at PTW 6 and 8. (2) Histological observation showed that the structure of the transplants in two groups was damaged at PTW 4. A moderate quantity of inflammatory cell infiltration could be observed. The amounts of the primary bone trabeculae and microvessels in group CBB were more abundant than those of group PCB, while the number of osteoclasts was less than those of group PCB. At PTW 6, the inflammatory cell infiltration in the transplants in both groups decreased obviously, the cuttlefish bone was found to be further degraded, and the number of newborn microvessels was increased. There were mature bone trabeculae around the transplants in both groups. And there were also mature bone trabeculae in the degraded CBB in group CBB. At PTW 8, the inflammatory reaction in the transplants in both groups disappeared; there were more mature bone trabeculae; the structure of the cuttlefish bone was found to be damaged basically. Bone trabeculae in group PCB were found around the transplant, while the bone trabeculae could be observed not only around the transplant but also in the degraded CBB in group CBB. The amount of the microvessels in group CBB was still larger than that of group PCB. (3) From PTW 4 to 8, the area of microvessel in group CBB [(63 ± 4), ( 136 ± 36), ( 347 ± 31) µm(2)] was larger than that in group PCB [(44 ± 7), (73 ± 4), (268 ± 42) µm(2), P < 0.05 or P < 0.01]. From PTW 4 to 8, the area of newborn bone in group CBB [(236 ± 26), (339 ± 42), (553 ± 40) µm(2)] was larger than that in group PCB [(137 ± 15), (243 ± 21), (445 ± 29) µm(2), with P values all below 0.01]. (4) The relation between the area of microvessel and the area of newborn bone was significantly positive (r = 0.948, P = 0.001). The CBB may exert good effect on osteogenesis and vascularization of rats with bone defect. It is a good three dimensional scaffold in bone tissue engineering.

Hepatic and skin metastases after laparoscopic radical prostatectomy for prostate cancer.

PubMed

Coman, Ioan; Crişan, Nicolae; Petrut, Bogdan; Bungărdean, Cătălina; Cristea, Tudor; Crişan, Dana

2007-09-01

Between 2004 and 2006, 50 radical prostatectomies were performed in our department, 46 of them through a laparoscopic approach addressed to early stage cancer (T1a,b,c and T2a,b,c N0 M0). We present the case of a 63 year old patient, who was initially diagnosed with prostate cancer in T1bN0M0 stage, Gleason score 8 and later presented atypical hepatic and trocar site metastases. This particular evolution of the case can be explained by the high value of the Gleason score and by the extension into microvessels observed on the sample prelevated by prostatectomy. The rarity of this atypical metastases and its association, the diagnostic and therapy problems are the reasons for the detailed presentation of this case.

Graft microvascular disease in solid organ transplantation.

PubMed

Jiang, Xinguo; Sung, Yon K; Tian, Wen; Qian, Jin; Semenza, Gregg L; Nicolls, Mark R

2014-08-01

Alloimmune inflammation damages the microvasculature of solid organ transplants during acute rejection. Although immunosuppressive drugs diminish the inflammatory response, they do not directly promote vascular repair. Repetitive microvascular injury with insufficient regeneration results in prolonged tissue hypoxia and fibrotic remodeling. While clinical studies show that a loss of the microvascular circulation precedes and may act as an initiating factor for the development of chronic rejection, preclinical studies demonstrate that improved microvascular perfusion during acute rejection delays and attenuates tissue fibrosis. Therefore, preservation of a functional microvasculature may represent an effective therapeutic strategy for preventing chronic rejection. Here, we review recent advances in our understanding of the role of the microvasculature in the long-term survival of transplanted solid organs. We also highlight microvessel-centered therapeutic strategies for prolonging the survival of solid organ transplants.

Platelet size and density affect shear-induced thrombus formation in tortuous arterioles

NASA Astrophysics Data System (ADS)

Chesnutt, Jennifer K. W.; Han, Hai-Chao

2013-10-01

Thrombosis accounts for 80% of deaths in patients with diabetes mellitus. Diabetic patients demonstrate tortuous microvessels and larger than normal platelets. Large platelets are associated with increased platelet activation and thrombosis, but the physical effects of large platelets in the microscale processes of thrombus formation are not clear. Therefore, the objective of this study was to determine the physical effects of mean platelet volume (MPV), mean platelet density (MPD) and vessel tortuosity on platelet activation and thrombus formation in tortuous arterioles. A computational model of the transport, shear-induced activation, collision, adhesion and aggregation of individual platelets was used to simulate platelet interactions and thrombus formation in tortuous arterioles. Our results showed that an increase in MPV resulted in a larger number of activated platelets, though MPD and level of tortuosity made little difference on platelet activation. Platelets with normal MPD yielded the lowest amount of mural thrombus. With platelets of normal MPD, the amount of mural thrombus decreased with increasing level of tortuosity but did not have a simple monotonic relationship with MPV. The physical mechanisms associated with MPV, MPD and arteriole tortuosity play important roles in platelet activation and thrombus formation.

A Reproducible Computerized Method for Quantitation of Capillary Density using Nailfold Capillaroscopy.

PubMed

Cheng, Cynthia; Lee, Chadd W; Daskalakis, Constantine

2015-10-27

Capillaroscopy is a non-invasive, efficient, relatively inexpensive and easy to learn methodology for directly visualizing the microcirculation. The capillaroscopy technique can provide insight into a patient's microvascular health, leading to a variety of potentially valuable dermatologic, ophthalmologic, rheumatologic and cardiovascular clinical applications. In addition, tumor growth may be dependent on angiogenesis, which can be quantitated by measuring microvessel density within the tumor. However, there is currently little to no standardization of techniques, and only one publication to date reports the reliability of a currently available, complex computer based algorithms for quantitating capillaroscopy data.(1) This paper describes a new, simpler, reliable, standardized capillary counting algorithm for quantitating nailfold capillaroscopy data. A simple, reproducible computerized capillaroscopy algorithm such as this would facilitate more widespread use of the technique among researchers and clinicians. Many researchers currently analyze capillaroscopy images by hand, promoting user fatigue and subjectivity of the results. This paper describes a novel, easy-to-use automated image processing algorithm in addition to a reproducible, semi-automated counting algorithm. This algorithm enables analysis of images in minutes while reducing subjectivity; only a minimal amount of training time (in our experience, less than 1 hr) is needed to learn the technique.

A Reproducible Computerized Method for Quantitation of Capillary Density using Nailfold Capillaroscopy

PubMed Central

Daskalakis, Constantine

2015-01-01

Capillaroscopy is a non-invasive, efficient, relatively inexpensive and easy to learn methodology for directly visualizing the microcirculation. The capillaroscopy technique can provide insight into a patient’s microvascular health, leading to a variety of potentially valuable dermatologic, ophthalmologic, rheumatologic and cardiovascular clinical applications. In addition, tumor growth may be dependent on angiogenesis, which can be quantitated by measuring microvessel density within the tumor. However, there is currently little to no standardization of techniques, and only one publication to date reports the reliability of a currently available, complex computer based algorithms for quantitating capillaroscopy data.1 This paper describes a new, simpler, reliable, standardized capillary counting algorithm for quantitating nailfold capillaroscopy data. A simple, reproducible computerized capillaroscopy algorithm such as this would facilitate more widespread use of the technique among researchers and clinicians. Many researchers currently analyze capillaroscopy images by hand, promoting user fatigue and subjectivity of the results. This paper describes a novel, easy-to-use automated image processing algorithm in addition to a reproducible, semi-automated counting algorithm. This algorithm enables analysis of images in minutes while reducing subjectivity; only a minimal amount of training time (in our experience, less than 1 hr) is needed to learn the technique. PMID:26554744

Participation of blood vessel cells in human adaptive immune responses.

PubMed

Pober, Jordan S; Tellides, George

2012-01-01

Circulating T cells contact blood vessels either when they extravasate across the walls of microvessels into inflamed tissues or when they enter into the walls of larger vessels in inflammatory diseases such as atherosclerosis. The blood vessel wall is largely composed of three cell types: endothelial cells lining the entire vascular tree; pericytes supporting the endothelium of microvessels; and smooth muscle cells forming the bulk of large vessel walls. Each of these cell types interacts with and alters the behavior of infiltrating T cells in different ways, making these cells active participants in the processes of immune-mediated inflammation. In this review, we compare and contrast what is known about the nature of these interactions in humans. Copyright © 2011 Elsevier Ltd. All rights reserved.

Complexity of tumor vasculature in clear cell renal cell carcinoma.

PubMed

Qian, Chao-Nan; Huang, Dan; Wondergem, Bill; Teh, Bin Tean

2009-05-15

Clear cell renal cell carcinoma (CCRCC) is a highly vascularized cancer resistant to conventional chemotherapy and radiotherapy. Antiangiogenic therapy has achieved some effectiveness against this unique malignancy. The complexity of the tumor vasculature in CCRCC has led to differences in correlating tumor microvessel density with patient prognosis. The authors' recent findings demonstrated that there were at least 2 major categories of tumor vessels in CCRCC-namely, undifferentiated and differentiated-correlating with patient prognosis in contrasting ways, with higher undifferentiated vessel density indicating poorer prognosis, and higher differentiated vessel density correlating with better prognosis. Furthermore, the presence of pericytes supporting the differentiated vessels varied in CCRCC. The distributions of pericyte coverage and differentiated vessels in CCRCC were uneven. The tumor margin had a higher pericyte coverage rate for differentiated vessels than did the inner tumor area. The uneven distributions of pericyte coverage and differentiated vessels in CCRCC prompted the authors to revisit the mechanism of tumor central necrosis, which was also known to be a prognostic indicator for CCRCC. The discrepancy of prognostic correlation between protein and messenger RNA levels of vascular endothelial growth factor in CCRCC was discussed. The complexity of the tumor vasculature in CCRCC also led the authors to begin to re-evaluate the therapeutic effects of antiangiogenic agents for each type of tumor vessel, which will in turn significantly broaden understanding of tumor angiogenesis and improve therapeutic effect. (c) 2009 American Cancer Society.

Vascular pericyte density and angiogenesis associated with adenocarcinoma of the prostate.

PubMed

Killingsworth, Murray C; Wu, Xiaojuan

2011-01-01

Angiogenesis facilitates metabolism, proliferation and metastasis of adenocarcinoma cells in the prostate, as without the development of new vasculature tumor growth cannot be sustained. However, angiogenesis is variable with the well-known phenomenon of vascular 'hotspots' seen associated with viable tumor cell mass. With the recent recognition of pericytes as molecular regulators of angiogenesis, we have examined the interaction of these cells in actively growing new vessels. Pericyte interactions with developing new vessels were examined using transmission electron microscopy. Pericyte distribution was mapped from α-SMA+ immunostained histological sections and quantified using image analysis. Data was obtained from peripheral and more central regions of 27 cases with Gleason scores of 4-9. Pericyte numbers were increased around developing new vessel sprouts at sites of luminal maturation. Numbers were reduced around the actively growing tips of migrating endothelial cells and functional new vessels. Tumor regions internal to a 500-μm peripheral band showed higher microvessel pericyte density than the peripheral region. Pericytes were found to be key cellular components of developing new vessels in adenocarcinoma of the prostate. Their numbers increased at sites of luminal maturation with these cells displaying an activated phenotype different to quiescent pericytes. Increased pericyte density was found internal to the peripheral region, suggesting more mature vessels lie more centrally. Copyright © 2011 S. Karger AG, Basel.

[Recombinant adeno-associated virus mediated RNA interference of angiogenin expression inhibits cell growth of human lung adenocarcinoma].

PubMed

Li, Bai-Ling; Zhang, Guan-Xin; Hou, Xiao-Lei; Tan, Meng-Wei; Yuan, Yang; Liu, Xiao-Hong; Gong, De-Jun; Huang, Sheng-Dong

2009-03-01

To study the inhibition of angiogenin (ANG) expression in human lung squamous cancer cell strain-A549 through adeno-associated virus (AAV)-mediated RNA-interference, and therefore to observe its effect on the growth of cancer cells and tumor formation. Recombinant AAV expressing H1-promoter-induced small-interference- RNA (siRNA) targeting ANG (AAV-shANG) was constructed, and then transfected into A549 cells. A549 cells and cells transfected with AAV-Null were used as the control groups. The effects of the reduced expression of ANG by RNAi from AAV-shANG on the growth, formation, reproduction, apoptosis, and microvessel-density of the carcinoma were observed. In vitro experiment showed that AAV-shANG was constructed successfully, There was an significant decrease in the expression of ANG protein 72 h after transfection, compared with the normal A459 cells and AAV-Null cells (P < 0.01). Cell cycle analysis showed that the proliferation index (PI) of normal A549 cells, AAV-Null cells and AAVshANG cells were 0.32 +/- 0.29, 0.35 +/- 0.38 and 0.31 +/- 0.43, respectively. There was no statistic difference in the PIs among the 3 groups (P > 0.05). In vivo experiment using thymus-defect mice showed that, there was an remarkable reduction in the mass and volume of tumors in AAV-shANG transfected group, compared to the control groups. Microvessel-density was 9.4 +/- 1.5, 9.8 +/- 2.1 and 5.7 +/- 1.9, respectively in the 3 groups, a statistic difference among the AAV-shANG-transfected group, the normal A549 group and the AAV-Null transfected group. The percentages of apoptotic cells in each group were (7.7 +/- 3.1)%, (8.5 +/- 5.4)%, (17.1 +/- 8.6)%, respectively, the experimental group being higher than those of the control groups. Positive rates of PCNA were (84.8 +/- 9.7)%, (85.8 +/- 9.8)%, and (70.4 +/- 10.1)%, respectively, the AAV-shANG transfected cancer cells showing a lower PCNA index than the control groups. AAV-mediated expression of siRNA could reduce the expression of ANG in cancer cells, significantly enough to inhibit cell proliferation, promote cell apoptosis and inhibit tumor growth.

Anti-cancer effects of baicalein in non-small cell lung cancer in-vitro and in-vivo.

PubMed

Cathcart, Mary-Clare; Useckaite, Zivile; Drakeford, Clive; Semik, Vikki; Lysaght, Joanne; Gately, Kathy; O'Byrne, Kenneth J; Pidgeon, Graham P

2016-09-01

Baicalein is a widely used Chinese herbal medicine derived from Scutellaria baicalenesis, which has been traditionally used as anti-inflammatory and anti-cancer therapy. In this study we examined the anti-tumour pathways activated following baicalein treatment in non-small cell lung cancer (NSCLC), both in-vitro and in-vivo. The effect of baicalein treatment on H-460 cells in-vitro was assessed using both BrdU assay (cell proliferation) and High Content Screening (multi-parameter apoptosis assay). A xenograft nude mouse model was subsequently established using these cells and the effect of baicalein on tumour growth and survival assessed in-vivo. Tumours were harvested from these mice and histological tissue analysis carried out. VEGF, 12-lipoxygenase and microvessel density (CD-31) were assessed by immunohistochemistry (IHC), while H and E staining was carried out to assess mitotic index. Gene expression profiling was carried out on corresponding RNA samples using Human Cancer Pathway Finder Arrays and qRT-PCR, with further gene expression analysis carried out using qRT-PCR. Baicalein significantly decreased lung cancer proliferation in H-460 cells in a dose dependent manner. At the functional level, a dose-dependent induction in apoptosis associated with decreased cellular f-actin content, an increase in nuclear condensation and an increase in mitochondrial mass potential was observed. Orthotopic treatment of experimental H-460 tumours in athymic nude mice with baicalein significantly (p < 0.05) reduced tumour growth and prolonged survival. Histological analysis of resulting tumour xenografts demonstrated reduced expression of both 12-lipoxygenase and VEGF proteins in baicalein-treated tumours, relative to untreated. A significant (p < 0.01) reduction in both mitotic index and micro-vessel density was observed following baicalein treatment. Gene expression profiling revealed a reduction (p < 0.01) in both VEGF and FGFR-2 following baicalein treatment, with a corresponding increase (p < 0.001) in RB-1. This study is the first to demonstrate efficacy of baicalein both in-vitro and in-vivo in NSCLC. These effects may be mediated in part through a reduction in both cell cycle progression and angiogenesis. At the molecular level, alterations in expression of VEGF, FGFR-2, and RB-1 have been implicated, suggesting a molecular mechanism underlying this in-vivo effect.

The relationship between aortic stiffness and changes in retinal microvessels among Asian ischemic stroke patients.

PubMed

De Silva, D A; Woon, F-P; Manzano, J J F; Liu, E Y; Chang, H-M; Chen, C; Wang, J J; Mitchell, P; Kingwell, B A; Cameron, J D; Lindley, R I; Wong, T Y; Wong, M-C

2012-12-01

Large-artery stiffness is a risk factor for stroke, including cerebral small-vessel disease. Retinal microvascular changes are thought to mirror those in cerebral microvessels. We investigated the relationship between aortic stiffness and retinal microvascular changes in Asian ischemic stroke patients. We studied 145 acute ischemic stroke patients in Singapore who had aortic stiffness measurements using carotid-femoral pulse wave velocity (cPWV). Retinal photographs were assessed for retinal microvessel caliber and qualitative signs of focal arteriolar narrowing, arteriovenous nicking and enhanced arteriolar light reflex. Aortic stiffening was associated with retinal arteriolar changes. Retinal arteriolar caliber decreased with increasing cPWV (r=-0.207, P=0.014). After adjusting for age, gender, hypertension, diabetes, mean arterial pressure and small-vessel stroke subtype, patients within the highest cPWV quartile were more likely to have generalized retinal arteriolar narrowing defined as lowest caliber tertile (odds ratio (OR) 6.84, 95% confidence interval (CI) 1.45-32.30), focal arteriolar narrowing (OR 13.85, CI 1.82-105.67), arteriovenous nicking (OR 5.08, CI 1.12-23.00) and enhanced arteriolar light reflex (OR 3.83, CI 0.89-16.48), compared with those within the lowest quartile. In ischemic stroke patients, aortic stiffening is associated with retinal arteriolar luminal narrowing as well as features of retinal arteriolosclerosis.

Cerebral vessels segmentation for light-sheet microscopy image using convolutional neural networks

NASA Astrophysics Data System (ADS)

Hu, Chaoen; Hui, Hui; Wang, Shuo; Dong, Di; Liu, Xia; Yang, Xin; Tian, Jie

2017-03-01

Cerebral vessel segmentation is an important step in image analysis for brain function and brain disease studies. To extract all the cerebrovascular patterns, including arteries and capillaries, some filter-based methods are used to segment vessels. However, the design of accurate and robust vessel segmentation algorithms is still challenging, due to the variety and complexity of images, especially in cerebral blood vessel segmentation. In this work, we addressed a problem of automatic and robust segmentation of cerebral micro-vessels structures in cerebrovascular images acquired by light-sheet microscope for mouse. To segment micro-vessels in large-scale image data, we proposed a convolutional neural networks (CNNs) architecture trained by 1.58 million pixels with manual label. Three convolutional layers and one fully connected layer were used in the CNNs model. We extracted a patch of size 32x32 pixels in each acquired brain vessel image as training data set to feed into CNNs for classification. This network was trained to output the probability that the center pixel of input patch belongs to vessel structures. To build the CNNs architecture, a series of mouse brain vascular images acquired from a commercial light sheet fluorescence microscopy (LSFM) system were used for training the model. The experimental results demonstrated that our approach is a promising method for effectively segmenting micro-vessels structures in cerebrovascular images with vessel-dense, nonuniform gray-level and long-scale contrast regions.

Interleukin 16- (IL-16-) Targeted Ultrasound Imaging Agent Improves Detection of Ovarian Tumors in Laying Hens, a Preclinical Model of Spontaneous Ovarian Cancer.

PubMed

Barua, Animesh; Yellapa, Aparna; Bahr, Janice M; Adur, Malavika K; Utterback, Chet W; Bitterman, Pincas; Basu, Sanjib; Sharma, Sameer; Abramowicz, Jacques S

2015-01-01

Limited resolution of transvaginal ultrasound (TVUS) scanning is a significant barrier to early detection of ovarian cancer (OVCA). Contrast agents have been suggested to improve the resolution of TVUS scanning. Emerging evidence suggests that expression of interleukin 16 (IL-16) by the tumor epithelium and microvessels increases in association with OVCA development and offers a potential target for early OVCA detection. The goal of this study was to examine the feasibility of IL-16-targeted contrast agents in enhancing the intensity of ultrasound imaging from ovarian tumors in hens, a model of spontaneous OVCA. Contrast agents were developed by conjugating biotinylated anti-IL-16 antibodies with streptavidin coated microbubbles. Enhancement of ultrasound signal intensity was determined before and after injection of contrast agents. Following scanning, ovarian tissues were processed for the detection of IL-16 expressing cells and microvessels. Compared with precontrast, contrast imaging enhanced ultrasound signal intensity significantly in OVCA hens at early (P < 0.05) and late stages (P < 0.001). Higher intensities of ultrasound signals in OVCA hens were associated with increased frequencies of IL-16 expressing cells and microvessels. These results suggest that IL-16-targeted contrast agents improve the visualization of ovarian tumors. The laying hen may be a suitable model to test new imaging agents and develop targeted anti-OVCA therapeutics.

Angiostatin inhibits experimental liver fibrosis in mice.

PubMed

Vogten, J Mathys; Drixler, Tamas A; te Velde, Elisabeth A; Schipper, Marguerite E; van Vroonhoven, Theo J M V; Voest, Emile E; Borel Rinkes, Inne H M

2004-07-01

Liver fibrosis is a response to chronic hepatic damage, which ultimately leads to liver failure and necessitates liver transplantation. A characteristic of fibrosis is pathological vessel growth. This type of angiogenesis may contribute to the disturbance of hepatocyte perfusion dynamics and lead to aggravation of disease. We hypothesized that angiostatin can inhibit pathological vessel growth and, consequently, the development of hepatic fibrosis. Hepatic fibrosis was induced by injection of carbon tetrachloride for 5 weeks. Angiostatin mice received carbon tetrachloride for 5 weeks and angiostatin during weeks 4 and 5. After 5 weeks, immunohistochemistry for endothelial cell marker von Willebrand factor and for cell proliferation was performed. Angiogenesis was quantified by counting the number of immunopositive microvessels. Also, the relative fibrotic surface was determined using Sirius Red histostaining and computer image analysis. Immunohistochemistry revealed increased expression for von Willebrand factor in fibrotic livers. Immunopositive microvessels were localized in fibrotic areas surrounding larger vessels and in emerging fibrotic septa. Angiostatin reduced the number of immunopositive microvessels by 69% (p<0.001). In addition, angiostatin reduced the relative fibrotic area in the liver by 63+/-0.1% (p<0.001). Finally, angiostatin treatment was not associated with differences in cell proliferation. Angiostatin inhibits the development of pathological angiogenesis and liver fibrosis in mice. These results warrant further evaluation of angiostatin as an antifibrotic agent, potentially contributing to the deferment of liver transplantation and reduced recurrence of fibrotic disease in the transplanted liver.

HSP27 Protects the Blood-Brain Barrier Against Ischemia-Induced Loss of Integrity

PubMed Central

Leak, Rehana K.; Zhang, Lili; Stetler, R. Anne; Weng, Zhongfang; Li, Peiying; Atkins, G. Brandon; Gao, Yanqin; Chen, Jun

2014-01-01

Loss of integrity of the blood-brain barrier (BBB) in stroke victims initiates a devastating cascade of events including extravasation of blood-borne molecules, water, and inflammatory cells deep into brain parenchyma. Thus, it is important to identify mechanisms by which BBB integrity can be maintained in the face of ischemic injury in experimental stroke. We previously demonstrated that the phylogenetically conserved small heat shock protein 27 (HSP27) protects against transient middle cerebral artery occlusion (tMCAO). Here we show that HSP27 transgenic overexpression also maintains the integrity of the BBB in mice subjected to tMCAO. Extravasation of endogenous IgG antibodies and exogenous FITC-albumin into the brain following tMCAO was reduced in transgenic mice, as was total brain water content. HSP27 overexpression abolished the appearance of TUNEL-positive profiles in microvessel walls. Transgenics also exhibited less loss of microvessel proteins following tMCAO. Notably, primary endothelial cell cultures were rescued from oxygen-glucose deprivation (OGD) by lentiviral HSP27 overexpression according to four viability assays, supporting a direct effect on this cell type. Finally, HSP27 overexpression reduced the appearance of neutrophils in the brain and inhibited the secretion of five cytokines. These findings reveal a novel role for HSP27 in attenuating ischemia/reperfusion injury - the maintenance of BBB integrity. Endogenous upregulation of HSP27 after ischemia in wild-type animals may exert similar protective functions and warrants further investigation. Exogenous enhancement of HSP27 by rational drug design may lead to future therapies against a host of injuries, including but not limited to a harmful breach in brain vasculature. PMID:23469858

Mechanics of smooth muscle in isolated single microvessels.

PubMed

Gore, R W; Davis, M J

1984-01-01

In vivo studies on frog mesenteric arterioles (4) indicate that segmental differences in the response of microvessels to physical and chemical stimuli can be explained simply in terms of the length-tension characteristics of vascular smooth muscle at different points along the vascular tree. Studies on single, isolated arterioles in vitro were initiated to examine more closely the validity of this explanation for regional response differences. This paper reports some of the results. First-, second-, and third-order arterioles (18-60 micron i.d.) were dissected from hamster cheek pouches. The vessels were cannulated with a modified Burg microperfusion system, and their mechanical properties studied using the methods described by Duling and Gore. Vessels were activated in four stages with K+ and norepinephrine. During activation, transmural pressures were adjusted to minimize vascular smooth-muscle shortening. Active pressure-diameter curves were recorded while adjusting transmural pressure through the range 5 to 400 cm H20 in 5-25 cm steps. Vessel dimensions were measured with a videomicrometer. Passive curves were obtained after equilibration overnight in Ca2+-free medium. The vessels were then fixed and prepared for histologic sectioning, and measurements of vessel-wall composition were made. The Laplace relationship was used to construct length-tension diagrams, and the histologic data were used to normalize the dimensional data to smooth-muscle lengths. Maximum active tension of second-order arterioles (1,170 dynes/cm) was two times previous values reported by Gore et al. This was due presumably to refinements in techniques and dissection procedures. Maximum active stress averaged 3.9 X 10(+6) dynes/cm2 for second-order arterioles. This number is identical to data obtained from hog carotid strips by Dillon et al.

Synthetic α-mangostin dilaurate strongly suppresses wide-spectrum organ metastasis in a mouse model of mammary cancer.

PubMed

Shibata, Masa-Aki; Hamaoka, Hitomi; Morimoto, Junji; Kanayama, Tadashi; Maemura, Kentaro; Ito, Yuko; Iinuma, Munekazu; Kondo, Yoichi

2018-03-30

We previously reported that, in a mouse model of mammary cancer, α-mangostin alone exhibits anti-metastatic properties. To enhance this anti-metastatic effect, we examined the efficacy of synthetic α-mangostin dilaurate (MGD), prepared by adding lauric acid to α-mangostin, in the same experimental system wherein mice bearing mammary tumors are exposed to dietary MGD at 0, 2000 and 4000 ppm. Lauric acid has a high propensity for lymphatic absorption, which is the most common pathway of initial dissemination of many solid malignancies. Both mammary tumor volumes and wide-spectrum organ metastasis were markedly reduced at 2000 and 4000 ppm: furthermore, survival in the 4000-ppm group was significantly greater than in control mice. Apoptosis in mammary carcinomas was also significantly increased in the 4000-ppm group, whereas blood microvessel density and lymphatic vessel invasion were markedly reduced. In real-time PCR analyses of tumor samples, increased p21 and decreased Pcna expression were observed with 4000 ppm but values were not statistically significant when compared to expression in control tumors. However, exposure to 4000 ppm significantly decreased expression of phospho-Akt (Ser473/Thr308) as compared to the control, indicating a role in the anti-tumorigenic effects of MGD. These findings suggest that MGD may be useful for adjuvant therapy and chemoprevention and that conjugated medium-chain fatty acids may enhance the efficacy of certain chemotherapeutic agents. © 2018 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

Apurinic/apyrimidinic endonuclease 1 regulates angiogenesis in a transforming growth factor β-dependent manner in human osteosarcoma.

PubMed

Jiang, Xuan; Shan, Jinlu; Dai, Nan; Zhong, Zhaoyang; Qing, Yi; Yang, Yuxing; Zhang, Shiheng; Li, Chongyi; Sui, Jiangdong; Ren, Tao; Li, Mengxia; Wang, Dong

2015-10-01

Angiogenesis plays an important role in tumor growth and metastasis and has been reported to be inversely correlated with overall survival of osteosarcoma patients. It has been shown that apurinic/apyrimidinic endonuclease 1 (APE1), a dually functional protein possessing both base excision repair and redox activities, is involved in tumor angiogenesis, although these mechanisms are not fully understood. Our previous study showed that the expression of transforming growth factor β (TGFβ) was significantly reduced in APE1-deficient osteosarcoma cells. Transforming growth factor β promotes cancer metastasis through various mechanisms including immunosuppression, angiogenesis, and invasion. In the current study, we initially revealed that APE1, TGFβ, and microvessel density (MVD) have pairwise correlation in osteosarcoma tissue samples, whereas TGFβ, tumor size, and MVD were inversely related to the prognosis of the cohort. We found that knocking down APE1 in osteosarcoma cells resulted in TGFβ downregulation. In addition, APE1-siRNA led to suppression of angiogenesis in vitro based on HUVECs in Transwell and Matrigel tube formation assays. Reduced secretory protein level of TGFβ of culture medium also resulted in decreased phosphorylation of Smad3 of HUVECs. In a mouse xenograft model, siRNA-mediated silencing of APE1 downregulated TGFβ expression, tumor size, and MVD. Collectively, the current evidence indicates that APE1 regulates angiogenesis in osteosarcoma by controlling the TGFβ pathway, suggesting a novel target for anti-angiogenesis therapy in human osteosarcoma. © 2015 The Authors. Cancer Science published by Wiley Publishing Asia Pty Ltd on behalf of Japanese Cancer Association.

Galectin-3 enhances angiogenic and migratory potential of microglial cells via modulation of integrin linked kinase signaling

PubMed Central

Wesley, Umadevi V.; Vemuganti, Raghu; Ayvaci, Rabia; Dempsey, Robert J.

2013-01-01

Focal cerebral ischemia initiates self-repair mechanisms that include the production of neurotrophic factors and cytokines. Galectin-3 is an important angiogenic cytokine. We have previously demonstrated that expression of galectin 3 (Gal-3), a carbohydrate binding protein is significantly upregulated in activated microglia in the brains of rats subjected to focal ischemia. Further blocking of Gal-3 function with Gal-3 neutralizing antibody decreased the microvessel density in ischemic brain. We currently show that Gal-3 significantly increases the viability of microglia BV2 cells subjected to oxygen glucose deprivation (OGD) and re-oxygenation. Exogenous Gal-3 promoted the formation of pro-angiogenic structures in an in vitro human umbilical vein endothelial (HUVEC) and BV2 cell co-culture model. Gal-3 induced angiogenesis was associated with increased expression of vascular endothelial growth factor. The conditioned medium of BV2 cells exposed to OGD contained increased Gal-3 levels, and promoted the formation of pro-angiogenic structures in an in vitro HUVEC culture model. Gal-3 also augmented the in vitro migratory potential of BV2 microglia. Gal-3 mediated functions were associated with increased levels of integrin-linked kinase (ILK) signaling as demonstrated by the impaired angiogenesis and migration of BV2 cells following targeted silencing of ILK expression by SiRNA. Furthermore, we show that ILK levels correlate with the levels of phos-AKT and ERK1/2 that are downstream effectors of ILK pathway. Taken together, our studies indicate that Gal-3 contributes to angiogenesis and microglia migration that may have implications in post stroke repair. PMID:23246924

Pericytes and endothelial precursor cells: cellular interactions and contributions to malignancy.

PubMed

Bagley, Rebecca G; Weber, William; Rouleau, Cecile; Teicher, Beverly A

2005-11-01

Tumor vasculature is irregular, abnormal, and essential for tumor growth. Pericytes and endothelial precursor cells (EPC) contribute to the formation of blood vessels under angiogenic conditions. As primary cells in culture, pericytes and EPC share many properties such as tube/network formation and response to kinase inhibitors selective for angiogenic pathways. Expression of cell surface proteins including platelet-derived growth factor receptor, vascular cell adhesion molecule, intercellular adhesion molecule, CD105, desmin, and neural growth proteoglycan 2 was similar between pericytes and EPC, whereas expression of P1H12 and lymphocyte function-associated antigen-1 clearly differentiates the cell types. Further distinction was observed in the molecular profiles for expression of angiogenic genes. Pericytes or EPC enhanced the invasion of MDA-MB-231 breast cancer cells in a coculture assay system. The s.c. coinjection of live pericytes or EPC along with MDA-MB-231 cells resulted in an increased rate of tumor growth compared with coinjection of irradiated pericytes or EPC. Microvessel density analysis indicated there was no difference in MDA-MB-231 tumors with or without EPC or pericytes. However, immunohistochemical staining of vasculature suggested that EPC and pericytes may stabilize or normalize vasculature rather than initiate vasculogenesis. In addition, tumors arising from the coinjection of EPC and cancer cells were more likely to develop lymphatic vessels. These results support the notion that pericytes and EPC contribute to malignancy and that these cell types can be useful as cell-based models for tumor vascular development and selection of agents that may provide therapeutic benefit.

Endothelin-A-receptor antagonism with atrasentan exhibits limited activity on the KU-19-19 bladder cancer cell line in a mouse model.

PubMed

Herrmann, Edwin; Tiemann, Arne; Eltze, Elke; Bolenz, Christian; Bremer, Christoph; Persigehl, Thorsten; Hertle, Lothar; Wülfing, Christian

2009-10-01

The endothelin axis consists of endothelin-1 (ET-1) and its two receptors, ET(A)- and ET(B)-receptor (ET(A)-R and ET(B)-R). In several tumor entities, the ET(A)-R plays a significant role as a drug target. In our study, we investigated whether inhibition of ET(A)-R with atrasentan leads to an antitumor effect in urinary bladder carcinoma as well. Twenty nude mice with thymic aplasia were subcutaneously administered 2 x 10(6) KU-19-19 bladder cancer cells in the right flank. Starting on the 22nd day after the injection, ten animals were treated with atrasentan (2.5 mg/kg BW intraperitoneally), and another ten animals were treated with placebo. During treatment, absolute tumor growth and relative growth rate over time were determined. After the end of treatment, the mitosis and necrosis rates, microvessel density, and receptor density in the tumor tissue were analyzed by immunohistochemistry. In addition, the expression intensities of ET-1, ET(A)-R, and ET(B)-R were evaluated semiquantitatively and compared between the groups. No significant differences between the active-treatment and placebo groups were detected, either with respect to absolute tumor growth (P = 0.333) or mitosis rate (P = 0.217). In the analysis of the necrosis rate and receptor density for ET(A)-R, a trend toward higher values in the active-treatment group (mean necrosis rate = 63.67%, receptor density: 1.417) than in the placebo group (mean necrosis rate = 46.25%, receptor density: 1.270) was found; however, neither difference was statistically significant (P = 0.08 and 0.219, respectively). ET(A)-R blockade with atrasentan in a bladder cancer xenograft model shows no significant antitumor effect.

Mathematical modeling of atherosclerotic plaque destabilization: Role of neovascularization and intraplaque hemorrhage.

PubMed

Guo, Muyi; Cai, Yan; Yao, Xinke; Li, Zhiyong

2018-08-07

Observational studies have identified angiogenesis from the adventitial vasa vasorum and intraplaque hemorrhage (IPH) as critical factors in atherosclerotic plaque progression and destabilization. Here we propose a mathematical model incorporating intraplaque neovascularization and hemodynamic calculation with plaque destabilization for the quantitative evaluation of the role of neoangiogenesis and IPH in the vulnerable atherosclerotic plaque formation. An angiogenic microvasculature is generated by two-dimensional nine-point discretization of endothelial cell proliferation and migration from the vasa vasorum. Three key cells (endothelial cells, smooth muscle cells and macrophages) and three key chemicals (vascular endothelial growth factors, extracellular matrix and matrix metalloproteinase) are involved in the plaque progression model, and described by the reaction-diffusion partial differential equations. The hemodynamic calculation of the microcirculation on the generated microvessel network is carried out by coupling the intravascular, interstitial and transvascular flow. The plasma concentration in the interstitial domain is defined as the description of IPH area according to the diffusion and convection with the interstitial fluid flow, as well as the extravascular movement across the leaky vessel wall. The simulation results demonstrate a series of pathophysiological phenomena during the vulnerable progression of an atherosclerotic plaque, including the expanding necrotic core, the exacerbated inflammation, the high microvessel density (MVD) region at the shoulder areas, the transvascular flow through the capillary wall and the IPH. The important role of IPH in the plaque destabilization is evidenced by simulations with varied model parameters. It is found that the IPH can significantly speed up the plaque vulnerability by increasing necrotic core and thinning fibrous cap. In addition, the decreased MVD and vessel permeability may slow down the process of plaque destabilization by reducing the IPH dramatically. We envision that the present model and its future advances can serve as a valuable theoretical platform for studying the dynamic changes in the microenvironment during the plaque destabilization. Copyright © 2018 Elsevier Ltd. All rights reserved.

Dual-wavelength photothermal optical coherence tomography for blood oxygen saturation measurement

NASA Astrophysics Data System (ADS)

Yin, Biwei; Kuranov, Roman V.; McElroy, Austin B.; Milner, Thomas E.

2013-03-01

We report design and demonstration of a dual wavelength photothermal (DWP) optical coherence tomography (OCT) system for imaging of a phantom microvessel and measurement of hemoglobin oxygen saturation (SO2) level. The DWP-OCT system contains a swept-source (SS) two-beam phase-sensitive (PhS) OCT system (1060 nm) and two intensity modulated photothermal excitation lasers (770 nm and 800 nm). The PhS-OCT probe beam (1060 nm) and photothermal excitation beams are combined into one single-mode optical fiber. A galvanometer based two-dimensional achromatic scanning system is designed to provide 14 μm lateral resolution for the PhS-OCT probe beam (1060 nm) and 13 μm lateral resolution for photothermal excitation beams. DWP-OCT system's sensitivity is 102 dB, axial resolution is 13 μm in tissue and uses a real-time digital dispersion compensation algorithm. Noise floor for optical pathlength measurements is 300 pm in the signal frequency range (380-400 Hz) of photothermal modulation frequencies. Blood SO2 level is calculated from measured optical pathlength (op) signal in a 300 μm diameter microvessel phantom introduced by the two photothermal excitation beams. En-face and B-scan images of a phantom microvessel are recorded, and six blood samples' SO2 levels are measured using DWP-OCT and compared with values provided by a commercial blood oximeter. A mathematical model indicates thermal diffusion introduces a systematic artifact that over-estimates SO2 values and is consistent with measured data.

A standalone perfusion platform for drug testing and target validation in micro-vessel networks

PubMed Central

Zhang, Boyang; Peticone, Carlotta; Murthy, Shashi K.; Radisic, Milica

2013-01-01

Studying the effects of pharmacological agents on human endothelium includes the routine use of cell monolayers cultivated in multi-well plates. This configuration fails to recapitulate the complex architecture of vascular networks in vivo and does not capture the relationship between shear stress (i.e. flow) experienced by the cells and dose of the applied pharmacological agents. Microfluidic platforms have been applied extensively to create vascular systems in vitro; however, they rely on bulky external hardware to operate, which hinders the wide application of microfluidic chips by non-microfluidic experts. Here, we have developed a standalone perfusion platform where multiple devices were perfused at a time with a single miniaturized peristaltic pump. Using the platform, multiple micro-vessel networks, that contained three levels of branching structures, were created by culturing endothelial cells within circular micro-channel networks mimicking the geometrical configuration of natural blood vessels. To demonstrate the feasibility of our platform for drug testing and validation assays, a drug induced nitric oxide assay was performed on the engineered micro-vessel network using a panel of vaso-active drugs (acetylcholine, phenylephrine, atorvastatin, and sildenafil), showing both flow and drug dose dependent responses. The interactive effects between flow and drug dose for sildenafil could not be captured by a simple straight rectangular channel coated with endothelial cells, but it was captured in a more physiological branching circular network. A monocyte adhesion assay was also demonstrated with and without stimulation by an inflammatory cytokine, tumor necrosis factor-α. PMID:24404058

Blood Vessel Adaptation with Fluctuations in Capillary Flow Distribution

PubMed Central

Hu, Dan; Cai, David; Rangan, Aaditya V.

2012-01-01

Throughout the life of animals and human beings, blood vessel systems are continuously adapting their structures – the diameter of vessel lumina, the thickness of vessel walls, and the number of micro-vessels – to meet the changing metabolic demand of the tissue. The competition between an ever decreasing tendency of luminal diameters and an increasing stimulus from the wall shear stress plays a key role in the adaptation of luminal diameters. However, it has been shown in previous studies that the adaptation dynamics based only on these two effects is unstable. In this work, we propose a minimal adaptation model of vessel luminal diameters, in which we take into account the effects of metabolic flow regulation in addition to wall shear stresses and the decreasing tendency of luminal diameters. In particular, we study the role, in the adaptation process, of fluctuations in capillary flow distribution which is an important means of metabolic flow regulation. The fluctuation in the flow of a capillary group is idealized as a switch between two states, i.e., an open-state and a close-state. Using this model, we show that the adaptation of blood vessel system driven by wall shear stress can be efficiently stabilized when the open time ratio responds sensitively to capillary flows. As micro-vessel rarefaction is observed in our simulations with a uniformly decreased open time ratio of capillary flows, our results point to a possible origin of micro-vessel rarefaction, which is believed to induce hypertension. PMID:23029014

Anti-TNFα therapy transiently improves high density lipoprotein cholesterol levels and microvascular endothelial function in patients with rheumatoid arthritis: a Pilot Study

PubMed Central

2012-01-01

Background Rheumatoid arthritis (RA) is associated with increased morbidity and mortality from cardiovascular disease (CVD). This can be only partially attributed to traditional CVD risk factors such as dyslipidaemia and their downstream effects on endothelial function. The most common lipid abnormality in RA is reduced levels of high-density lipoprotein (HDL) cholesterol, probably due to active inflammation. In this longitudinal study we hypothesised that anti-tumor necrosis factor-α (anti-TNFα) therapy in patients with active RA improves HDL cholesterol, microvascular and macrovascular endothelial function. Methods Twenty-three RA patients starting on anti-TNFα treatment were assessed for HDL cholesterol level, and endothelial-dependent and -independent function of microvessels and macrovessels at baseline, 2-weeks and 3 months of treatment. Results Disease activity (CRP, fibrinogen, DAS28) significantly decreased during the follow-up period. There was an increase in HDL cholesterol levels at 2 weeks (p < 0.05) which was paralleled by a significant increase in microvascular endothelial-dependent function (p < 0.05). However, both parameters returned towards baseline at 12 weeks. Conclusion Anti-TNFα therapy in RA patients appears to be accompanied by transient but significant improvements in HDL cholesterol levels, which coexists with an improvement in microvascular endothelial-dependent function. PMID:22824166

Paracrine action of HO-1-modified mesenchymal stem cells mediates cardiac protection and functional improvement.

PubMed

Zeng, Bin; Ren, Xiaofeng; Lin, Guosheng; Zhu, Chengang; Chen, Honglei; Yin, Jiechao; Jiang, Hong; Yang, Bo; Ding, Danhua

2008-10-01

The aim has been to determine whether the supernatants of mesenchymal stem cells (MSCs) transfected with adenovirus carrying human heme oxygenase-1 (hHO-1) gene protect cardiomyocytes from ischemic injury. We have found that hHO-1 infected MSCs (hHO-1-MSCs) increased expression of hHO-1 protein. Apoptosis of cultured hHO-1-MSCs exposed to hypoxia was suppressed. Several cytokines, including HGF, bFGF, TGF-beta, VEGF and IL-1beta, were produced by hHO-1-MSCs, some being significantly enhanced under hypoxia stimulation. Meanwhile, those cytokines reduced caspase-3 level and activity in cultured adult rat ventricular cardiomyocytes (ARVCs) exposed to hypoxia. Supernatants obtained from hHO-1-MSCs improved left ventricular function, limited myocardial infarct size, increased microvessel density, and inhibited apoptosis of cardiomyocytes in rat myocardial infarction. It can be concluded hHO-1-modified MSCs prevent myocardial cell injury via secretion of paracrine-acting mediators.

The vascularization pattern of acellular nerve allografts after nerve repair in Sprague-Dawley rats.

PubMed

Zhu, Zhaowei; Huang, Yanyan; Zou, Xiaoyan; Zheng, Canbin; Liu, Jianghui; Qiu, Longhai; He, Bo; Zhu, Qingtang; Liu, Xiaolin

2017-11-01

We have demonstrated that angiogenesis in acellular nerve allografts (ANAs) can promote neuroregeneration. The present study aimed to investigate the microvascular regeneration pattern of ANAs in Sprague-Dawley (SD) rats. Sixty male SD rats were randomly divided into an autologous group and a rat acellular nerve allograft group (rANA), and 10-mm sciatic nerve defects were induced in these rats. On the 7th, 14th and 21st days after surgery, systemic perfusion with Evans Blue (EB) or lead oxide was performed on the rats through carotid intubation. Samples were then collected for gross observation, and the microvessels in the nerves were reconstructed through microscopic CT scans using MIMICS software. The vascular volume fraction (VF, %) and microvessel growth rate (V, mm/d) in both groups were then measured, and 1 month after surgery, NF-200 staining was performed to observe and compare the growth condition of the axons. Early post-operative perfusion with gelatin/EB showed EB permeation around the acellular nerve. Perfusion with gelatin/lead oxide showed that the blood vessels had grown into the allograft from both ends 7 days after the operation. Fourteen days after the operation, the microvessel growth rate of the autologous group was faster than that of the rANA group (0.39 ± 0.17 mm/d vs. 0.26 ± 0.14 mm/d, p < 0.05), and the vascular VF was also higher than that of the rANA group (8.92% ± 1.54% vs. 6.31% ± 1.21%, p < 0.05). Twenty-one days after the operation, the blood vessels at both ends of the allograft had connected to form a microvessel network. The growth rate was not significantly different between the two groups; however, the vascular VF of the autologous group was higher than that of the rANA group (12.18% ± 2.27% vs. 9.92% ± 0.84%, p < 0.05). One month after the operation, the NF-200 fluorescence (IOD) in the autologous group significantly increased compared with that of the rANA group (540,278 ± 17,424 vs. 473,310 ± 14,636, respectively, p < 0.05), suggesting that the results of the repair after nerve injury were significantly better in the autologous group than in the rANA group. Both the autologous nerve and ANAs rely on the permeation of tissue fluids to supply nutrients during the early stage, and microvessel growth mainly starts at both ends of the graft and enters the graft along the long axis. Compared to ANAs, the growth speed of revascularization in autologous nerve grafts was faster, leading to a better outcome in the autologous nerve group.

[Dynamic change in microcirculation of pancreas after experimental high-voltage electric burn].

PubMed

Zhang, Qing-fu; Bai, Yong-qiang

2009-10-01

To observe the changes in surface microcirculation of pancreas after high-voltage electric burn (HEB). Thirty rabbits were divided into electrical injury (E) group and control (C) group in a simple random method, with 15 rabbits in each group. Rabbit model of HEB was reproduced from E group with TC-30-20KVA type voltage regulator and YDJ-10KVA type experimental transformer. Rabbits in C group were shamly burned with the same equipment as in E group but not electrified. Intravenous blood of rabbits in both groups was drawn 15 mins before HEB and 0, 1, 2, 4, 8 h after to determine the levels of serum amylase and blood glucose. The morphology of the pancreas microvessels and its surrounding tissues, and the dynamic changes in microvascular blood flow were observed with WX-9 microscope and its image analytical system. The level of serum amylase of rabbits in E group increased gradually and peaked (849 +/- 39) U/L at 8 post HEB h (PHH), which decreased gradually reaching the nadir (153 +/- 21) U/L at 8 PHH in C group (P < 0.05). The blood glucose levels of rabbits in E group and C group increased gradually, with the former level obviously higher than the latter (P < 0.05). Arteriole, venule and capillary network on the surface of pancreatic lobules of rabbits in both groups were clearly seen and well-distributed in the natural way before HEB. In E group, arterioles of rabbits contracted at 0 PHH, and increased gradually in caliber size at 1 PHH; venules of rabbits were unevenly thickened at 2 PHH, and dilated at 8 PHH; the capillaries were contracted or with interrupted flow or completely obstructed at 0 PHH, and their thickness were uneven at 2 PHH, showing exudation at 8 PHH. There was no obvious change of microvessels in rabbits in C group at each time point. There was no exudation and bleeding around the microvessels on the pancreas surface of rabbits in both groups before HEB. In E group exudation was observed around microvessels at 1 PHH, bleeding was observed at 2 PHH and became obvious at 4 PHH; exudation and diffuse bleeding from capillaries were observed at 8 PHH. There was no exudation and bleeding in rabbits in C group as observed at each time point. Before HEB, blood flow speed in microvessels of rabbits in 2 groups was similar to each other (P > 0.05), and no erythrocyte aggregation or microthrombus was found in both groups. In E group, blood flow speed slowed down at 0 PHH as compared with that before HEB, it accelerated at 1 h and slowed down later; erythrocyte aggregation in venules and capillaries was found at 0 PHH, and it aggregated gradually. No above-mentioned change was found in C group. HEB produces microcirculation disturbance and functional disturbance of pancreas.

Deregulation of tumor angiogenesis and blockade of tumor growth in PPARbeta-deficient mice.

PubMed

Müller-Brüsselbach, Sabine; Kömhoff, Martin; Rieck, Markus; Meissner, Wolfgang; Kaddatz, Kerstin; Adamkiewicz, Jürgen; Keil, Boris; Klose, Klaus J; Moll, Roland; Burdick, Andrew D; Peters, Jeffrey M; Müller, Rolf

2007-08-08

The peroxisome proliferator-activated receptor-beta (PPARbeta) has been implicated in tumorigenesis, but its precise role remains unclear. Here, we show that the growth of syngeneic Pparb wild-type tumors is impaired in Pparb(-/-) mice, concomitant with a diminished blood flow and an abundance of hyperplastic microvascular structures. Matrigel plugs containing pro-angiogenic growth factors harbor increased numbers of morphologically immature, proliferating endothelial cells in Pparb(-/-) mice, and retroviral transduction of Pparb triggers microvessel maturation. We have identified the Cdkn1c gene encoding the cell cycle inhibitor p57(Kip2) as a PPARbeta target gene and a mediator of the PPARbeta-mediated inhibition of cell proliferation, which provides a possible mechanistic explanation for the observed tumor endothelial hyperplasia and deregulation of tumor angiogenesis in Pparb(-/-) mice. Our data point to an unexpected essential role for PPARbeta in constraining tumor endothelial cell proliferation to allow for the formation of functional tumor microvessels.

Live-cell imaging of invasion and intravasation in an artificial microvessel platform.

PubMed

Wong, Andrew D; Searson, Peter C

2014-09-01

Methods to visualize metastasis exist, but additional tools to better define the biologic and physical processes underlying invasion and intravasation are still needed. One difficulty in studying metastasis stems from the complexity of the interface between the tumor microenvironment and the vascular system. Here, we report the development of an investigational platform that positions tumor cells next to an artificial vessel embedded in an extracellular matrix. On this platform, we used live-cell fluorescence microscopy to analyze the complex interplay between metastatic cancer cells and a functional artificial microvessel that was lined with endothelial cells. The platform recapitulated known interactions, and its use demonstrated the capabilities for a systematic study of novel physical and biologic parameters involved in invasion and intravasation. In summary, our work offers an important new tool to advance knowledge about metastasis and candidate antimetastatic therapies. ©2014 American Association for Cancer Research.

Fluorescein isothiocyanate (FITC)-Dextran Extravasation as a Measure of Blood-Brain Barrier Permeability

PubMed Central

Natarajan, Reka; Northrop, Nicole

2017-01-01

The blood-brain barrier (BBB) is formed in part by vascular endothelial cells that constitute the capillaries and microvessels of the brain. The function of this barrier is to maintain homeostasis within the brain microenvironment and buffer the brain from changes in the periphery. A dysfunction of the BBB would permit circulating molecules and pathogens typically restricted to the periphery to enter the brain and interfere with normal brain function. As increased permeability of the BBB is associated with several neuropathologies, it is important to have a reliable and sensitive method that determines BBB permeability and the degree of BBB disruption. A detailed protocol is presented for assessing the integrity of the BBB by transcardial perfusion of a 10,000 Da FITC labeled dextran molecule and its visualization to determine the degree of extravasation from brain microvessels. PMID:28398646

Microcirculation of the pancreas. A quantitative study of physiology and changes in pancreatitis.

PubMed

Klar, E; Endrich, B; Messmer, K

1990-02-01

A rabbit model was designed to study the microcirculation of the pancreas with special reference to changes occurring during acute pancreatitis. Intravital microscopy was used in conjunction with video techniques allowing for continuous observation and off-line evaluation of microvessel diameters and blood cell velocities. Based on the microvessel geometry a functional microvascular unit could be defined at the level of the pancreatic lobule consisting of intralobular arteries and veins and an arcade-like preferential pathway framing the capillary network. Experimental acute pancreatitis resulted in immediate leakage of the macromolecular plasma marker (FITC-Dextran 70) from the microvasculature suggesting increased permeability. In contrast to control conditions, pancreatic capillaries were excluded from the circulation during acute pancreatitis starting 30 min after induction with only single capillaries remaining perfused after 3 hours. At the same time, there was constant blood flow through the preferential pathways representing shunt perfusion.

In-vivo visualization of melanoma tumor microvessels and blood flow velocity changes accompanying tumor growth

NASA Astrophysics Data System (ADS)

Ishida, Hiroki; Hachiga, Tadashi; Andoh, Tsugunobu; Akiguchi, Shunsuke

2012-11-01

We demonstrate that using micro multipoint laser Doppler velocimetry (μ-MLDV) for noninvasive in-vivo imaging of blood vessels is useful for diagnosing malignant melanomas by comparison with visual diagnosis by dermoscopy. The blood flow velocity in microvessels varied during growth of melanomas transplanted in mouse ears. Mouse ears were observed by μ-MLDV up to 16 days after transplantation. The blood flow velocity in the tumor increased with increasing time and reached maximum of 4.5 mm/s at 9 days, which is more than twice that prior to transplantation. After 12 days, when the lesion had grown to an area of 6.6 mm2, we observed the formation of new blood vessels in the tumor. Finally, when the lesion had an area of 18 mm2 after 16 days, the flow velocity in the tumor decreased to approximately 3.2 mm/s.

Hyperforin acts as an angiogenesis inhibitor.

PubMed

Schempp, Christoph M; Kiss, Judit; Kirkin, Vladimir; Averbeck, Marco; Simon-Haarhaus, Birgit; Kremer, Bernhard; Termeer, Christian C; Sleeman, Jonathan; Simon, Jan C

2005-11-01

Hyperforin is a plant compound from Hypericum perforatum that inhibits tumor cell proliferation in vitro by induction of apoptosis. Here, we report that hyperforin also acts as an angiogenesis inhibitor in vitro and in vivo. In vitro, hyperforin blocked microvessel formation of human dermal microvascular endothelial cells (HDMEC) on a complex extracellular matrix. Furthermore, hyperforin reduced proliferation of HDMEC in a dose-dependent manner, without displaying toxic effects or inducing apoptosis of the cells. To evaluate the antiangiogenic activity of hyperforin in vivo, Wistar rats were subcutaneously injected with MT-450 mammary carcinoma cells and were treated with peritumoral injections of hyperforin or solvent. Hyperforin significantly inhibited tumor growth, induced apoptosis of tumor cells and reduced tumor vascularization, as shown by in situ staining of CD31-positive microvessels in the tumor stroma. These data suggest that, in addition to the induction of tumor cell apoptosis, hyperforin can also suppress angiogenesis by a direct, non-toxic effect on endothelial cells.

[Morphological signs of mitochondrial cytopathy in skeletal muscles and micro-vessel walls in a patient with cerebral artery dissection associated with MELAS syndrome].

PubMed

Sakharova, A V; Kalashnikova, L A; Chaĭkovskaia, R P; Mir-Kasimov, M F; Nazarova, M A; Pykhtina, T N; Dobrynina, L A; Patrusheva, N L; Patrushev, L I; Protskiĭ, S V

2012-01-01

Skin and muscles biopsy specimens of a patient harboring A3243G mutation in mitochondrial DNA, with dissection of internal carotid and vertebral arteries, associated with MELAS were studied using histochemical and electron-microscopy techniques. Ragged red fibers, regional variability of SDH histochemical reaction, two types of morphologically atypical mitochondria and their aggregation were found in muscle. There was correlation between SDH histochemical staining and number of mitochondria revealed by electron microscopy in muscle tissue. Similar mitochondrial abnormality, their distribution and cell lesions followed by extra-cellular matrix mineralization were found in the blood vessel walls. In line with generalization of cytopathy process caused by gene mutation it can be supposed that changes found in skin and muscle microvessels also exist in large cerebral vessels causing the vessel wall "weakness", predisposing them to dissection.

Microvascular Guidance: A Challenge to Support the Development of Vascularised Tissue Engineering Construct

PubMed Central

Sukmana, Irza

2012-01-01

The guidance of endothelial cell organization into a capillary network has been a long-standing challenge in tissue engineering. Some research efforts have been made to develop methods to promote capillary networks inside engineered tissue constructs. Capillary and vascular networks that would mimic blood microvessel function can be used to subsequently facilitate oxygen and nutrient transfer as well as waste removal. Vascularization of engineering tissue construct is one of the most favorable strategies to overpass nutrient and oxygen supply limitation, which is often the major hurdle in developing thick and complex tissue and artificial organ. This paper addresses recent advances and future challenges in developing three-dimensional culture systems to promote tissue construct vascularization allowing mimicking blood microvessel development and function encountered in vivo. Bioreactors systems that have been used to create fully vascularized functional tissue constructs will also be outlined. PMID:22623881

Loss of Endothelial Barrier Antigen Immunoreactivity in Rat Retinal Microvessels is Correlated with Clostridium perfringens Type D Epsilon Toxin-induced Damage to the Blood-Retinal Barrier.

PubMed

Mander, K A; Finnie, J W

2018-01-01

Clostridium perfringens type D epsilon toxin (ETX) is a potent neurotoxin producing a severe, and often fatal, neurological disorder in ruminant livestock. Microvascular damage appears to be the fundamental action of ETX in the brain and, recently, similar vascular injury, with subsequent severe vasogenic oedema, has been reported in the retina of rats given ETX. Endothelial barrier antigen (EBA) is a useful marker of an intact blood-brain barrier in rats and it has been shown that loss of EBA immunoreactivity is correlated with ETX-induced cerebral microvascular damage in this species. This paper reports, for the first time, that loss of EBA immunoexpression also occurs in rat retinal microvessels exposed to ETX, the marked reduction in EBA immunopositivity acting as a useful marker for blood-retinal barrier breakdown produced by this neurotoxin. Copyright © 2017 Elsevier Ltd. All rights reserved.

Microvasculature remodeling in the mouse lower gut during inflammaging

PubMed Central

Jeong, Jae-Ho; Kim, KwangSoo; Lim, Daejin; Kim, Kun-Hee; Kim, Hyung-Seok; Lee, Sungsu; Song, Joo-Hye; Moon, Byoung-Gon; Choy, Hyon E.; Park, Sang Chul

2017-01-01

Inflammaging is defined as low-grade, chronic, systemic inflammation in aging, in the absence of overt infection. Age-associated deterioration of gastrointestinal function could be ascribed to the inflammaging, although evidence is yet to emerge. Here we show that microvessels in aging mouse intestine were progressively deprived of supportive structures, microvessel-associated pericytes and adherens junction protein vascular endothelial (VE)-cadherin, and became leaky. This alteration was ascribed to up-regulation of angiopoetin-2 in microvascular endothelial cells. Up-regulation of the angiopoietin-2 was by TNF-α, originated from M2-like residential CD206+ macrophages, proportion of which increases as animal ages. It was concluded that antigenic burdens encountered in intestine throughout life create the condition of chronic stage of inflammation, which accumulates M2-like macrophages expressing TNF-α. The TNF-α induces vascular leakage to facilitate recruitment of immune cells into intestine under the chronic inflammatory setting. PMID:28045067

ABT-510 is an effective chemopreventive agent in the mouse 4-nitroquinoline 1-oxide model of oral carcinogenesis.

PubMed

Hasina, Rifat; Martin, Leslie E; Kasza, Kristen; Jones, Colleen L; Jalil, Asif; Lingen, Mark W

2009-04-01

Despite numerous advances, the 5-year survival rate for head and neck squamous cell cancer (HNSCC) has remained largely unchanged. This poor outcome is due to several variables, including the development of multiple primary tumors. Therefore, it is essential to supplement early detection with preventive strategies. Using the 4-nitroquinoline 1-oxide (4-NQO) mouse model, we sought to define an appropriate dose and duration of administration that would predict the histologic timeline of HNSCC progression. Additionally, we sought to determine the timing of the onset of the angiogenic phenotype. Finally, using ABT-510 as a proof-of-principle drug, we tested the hypothesis that inhibitors of angiogenesis can slow/delay the development of HNSCC. We determined that 8 weeks of 100 microg/mL 4-NQO in the drinking water was the optimal dosage and duration to cause a sufficient incidence of hyperkeratoses, dysplasias, and HNSCC over a period of 32 weeks with minimal morbidity and mortality. Increased microvessel density and vascular endothelial growth factor expression in hyperkeratotic lesions provided evidence that the initiation of the angiogenic phenotype occurred before the development of dysplasia. Importantly, ABT-510 significantly decreased the overall incidence of HNSCC from 37.3% to 20.3% (P = 0.021) as well as the combined incidence of dysplasia and HNSCC from 82.7% to 50.6% (P < 0.001). These findings suggest that our refinement of the 4-NQO model allows for the investigation of the histologic, molecular, and biological alterations that occur during the premalignant phase of HNSCC. In addition, these data support the hypothesis that inhibitors of angiogenesis may be promising chemopreventive agents.

Cell expression patterns of CD147 in N-diethylnitrosamine/phenobarbital-induced mouse hepatocellular carcinoma.

PubMed

Lu, Meng; Wu, Jiao; He, Feng; Wang, Xi-Long; Li, Can; Chen, Zhi-Nan; Bian, Huijie

2015-02-01

Overexpression of CD147/basigin in hepatic cells promotes the progression of hepatocellular carcinoma (HCC). Whether CD147 also expressed in liver non-parenchymal cells and associated with HCC development was unknown. The aim of the study was to explore time-dependent cell expression patterns of CD147 in a widely accepted N-diethylnitrosamine/phenobarbital (DEN/PB)-induced HCC mouse model. Liver samples collected at month 1-12 of post-DEN/PB administration were assessed the localization of CD147 in hepatocytes, endothelial cells, hepatic stellate cells, and macrophages. Immunohistochemistry analysis showed that CD147 was upregulated in liver tumors during month 1-8 of DEN/PB induction. Expression of CD147 was positively correlated with cytokeratin 18, a hepatocyte marker (r = 0.7857, P = 0.0279), CD31 (r = 0.9048, P = 0.0046), an endothelial cell marker, and CD68, a macrophage marker (r = 0.7619, P = 0.0368). A significant correlation was also observed between CD147 and alpha-smooth muscle actin (r = 0.8857, P = 0.0333) at DEN/PB initiation and early stage of tumor formation. Immunofluorescence and fluorescence in situ hybridization showed that CD147 co-expressed with cytokeratin 18, CD31, alpha-smooth muscle actin, and CD68. Moreover, there existed positive correlations between CD147 and microvessel density (r = 0.7857, P = 0.0279), CD147 and Ki-67 (r = 0.9341, P = 0.0022) in the development of DEN/PB-induced HCC. In conclusion, our results demonstrated that CD147 was upregulated in the liver parenchymal and mesenchymal cells and involved in angiogenesis and tumor cell proliferation in the development of DEN/PB-induced HCC.

Blood-filled cerebrospinal fluid-enhanced pericyte microvasculature contraction in rat retina: A novel in vitro study of subarachnoid hemorrhage

PubMed Central

Liu, Zhi; Li, Qiang; Cui, Gaoyu; Zhu, Gang; Tang, Weihua; Zhao, Hengli; Zhang, John H.; Chen, Yujie; Feng, Hua

2016-01-01

Previously, it was widely accepted that the delayed ischemic injury and poor clinical outcome following subarachnoid hemorrhage (SAH) was caused by cerebral vasospasm. This classical theory was challenged by a clazosentan clinical trial, which failed to improve patient outcome, despite reversing angiographic vasospasm. One possible explanation for the results of this trial is the changes in microcirculation following SAH, particularly in pericytes, which are the primary cell type controlling microcirculation in the brain parenchyma. However, as a result of technical limitations and the lack of suitable models, there was no direct evidence of microvessel dysfunction following SAH. In the present study, whole-mount retinal microvasculature has been introduced to study microcirculation in the brain following experimental SAH in vitro. Artificial blood-filled cerebrospinal fluid (BSCF) was applied to the retinal microvasculature to test the hypothesis that the presence of subarachnoid blood affects the contractile properties of the pericytes containing cerebral microcirculation during the early phase of SAH. It was observed that BCSF induced retina microvessel contraction and that this contraction could be resolved by BCSF wash-out. Furthermore, BCSF application accelerated pericyte-populated collagen gel contraction and increased the expression of α-smooth muscle actin. In addition, BCSF induced an influx of calcium in cultured retinal pericytes. In conclusion, the present study demonstrates increased contractility of retinal microvessels and pericytes in the presence of BCSF in vitro. These findings suggest that pericyte contraction and microvascular dysfunction is induced following SAH, which could lead to greater susceptibility to SAH-induced ischemia. PMID:27698742

Oxygen gradients in the microcirculation.

PubMed

Pittman, R N

2011-07-01

Early in the last century August Krogh embarked on a series of seminal studies to understand the connection between tissue metabolism and mechanisms by which the cardiovascular system supplied oxygen to meet those needs. Krogh recognized that oxygen was supplied from blood to the tissues by passive diffusion and that the most likely site for oxygen exchange was the capillary network. Studies of tissue oxygen consumption and diffusion coefficient, coupled with anatomical studies of capillarity in various tissues, led him to formulate a model of oxygen diffusion from a single capillary. Fifty years after the publication of this work, new methods were developed which allowed the direct measurement of oxygen in and around microvessels. These direct measurements have confirmed the predictions by Krogh and have led to extensions of his ideas resulting in our current understanding of oxygenation within the microcirculation. Developments during the last 40 years are reviewed, including studies of oxygen gradients in arterioles, capillaries, venules, microvessel wall and surrounding tissue. These measurements were made possible by the development and use of new methods to investigate oxygen in the microcirculation, so mention is made of oxygen microelectrodes, microspectrophotometry of haemoglobin and phosphorescence quenching microscopy. Our understanding of oxygen transport from the perspective of the microcirculation has gone from a consideration of oxygen gradients in capillaries and tissue to the realization that oxygen has the ability to diffuse from any microvessel to another location under the conditions that there exists a large enough PO(2) gradient and that the permeability for oxygen along the intervening pathway is sufficient. © 2011 The Author. Acta Physiologica © 2011 Scandinavian Physiological Society.

Protein-bounded uremic toxin p-cresylsulfate induces vascular permeability alternations.

PubMed

Tang, Wei-Hua; Wang, Chao-Ping; Yu, Teng-Hung; Tai, Pei-Yang; Liang, Shih-Shin; Hung, Wei-Chin; Wu, Cheng-Ching; Huang, Sung-Hao; Lee, Yau-Jiunn; Chen, Shih-Chieh

2018-06-01

The goal of the present studies is to investigate that the impact of p-cresylsulfate (PCS) on the endothelial barrier integrity via in situ exposure and systemic exposure. Vascular permeability changes induced by local injection of PCS were evaluated by the techniques of both Evans blue (EB) and India ink tracer. Rats were intravenously injected with EB or India ink followed by intradermal injections of various doses of PCS (0, 0.4, 2, 10 and 50 µmol/site) on rat back skins. At different time points, skin EB was extracted and quantified. The administration of India ink was used to demonstrate leaky microvessels. Skin PCS levels were also determined by liquid chromatography-mass spectrometry. We also investigated whether the increased endothelial leakage occurred in the aortic endothelium in rats treated with 5/6 nephrectomy and intraperitoneal injection of PCS 50 mg/kg/day for 4 weeks. The aortic endothelial integrity was evaluated by increased immunoglobulin G (IgG) leakage. High doses of PCS, but not lower doses, significantly induced vascular leakage as compared to saline injection and EB leakage exhibited in time-dependent manner. A time-correlated increase in leaky microvessels was detected in the tissues examined. The injected PCS declined with time and displayed an inverse relationship with vascular leakage. Chronic kidney disease (CKD) rats administered with PCS, compared to control rats, had significantly higher serum levels of PCS and apparent IgG deposition in the aortic intima. Increased endothelial leakage induced by PCS in skin microvessels and the aorta of CKD rats suggests that the PCS-induced endothelial barrier dysfunction.

Effect of intraplaque angiogenesis to atherosclerotic rupture-prone plaque induced by high shear stress in rabbit model

PubMed Central

Qiu, Juhui; Lei, Daoxi; Hu, Jianjun; Yin, Tieying; Zhang, Kang; Yu, Donghong

2017-01-01

Abstract Atherosclerotic prone-rupture plaque is mainly localized in the region of the entrance to the stenosis with high shear stress and the reasons are largely unknown. Our hypothesis is that such a distribution of cells in atherosclerotic plaque may depend on the angiogenesis. Silastic collars induced regions of high shear stress (20.68 ± 5.27 dynes/cm2) in the upstream flow and low shear stress (12.25 ± 1.28 dynes/cm2) in the downstream flow in carotid arteries. Compared with the low shear stress region, plaques in the high shear stress region showed more intraplaque haemorrhaging, less collagen and higher apoptotic rates of vascular smooth muscle cells; endothelial cells (ECs) in the high shear stress region were characterized with integrity and high endothelial nitric oxide synthase (eNOS) expression (1570.3 ± 345.5% vs 172.9 ± 49.9%). The number of intraplaque microvessels is very high in the high shear stress region (15 ± 1.8 n/mm2 vs 3.5 ± 0.4 n/mm2), and the microvessels in the plaque show ECs were abnormal, with membrane blebs, intracytoplasmic vacuoles and leukocyte infiltration. Our current study reveals that the integrity of the endothelium and the vulnerability of atherosclerotic plaques are simultaneously localized in high shear stress regions, and we provide evidence for the first time that microvessels in the intraplaque maybe responsible for rupture-prone plaque formation in the high shear stress region. PMID:28798867

Interactive effects of acupuncture on pain and distress in major burns: An experiment with rats.

PubMed

Abali, Ayse Ebru; Cabioglu, Tugrul; Ozdemir, Handan; Haberal, Mehmet

2015-06-01

This study sought to investigate the interactive effects of acupuncture on pain and distress and the local progress in the burn wound in an experimental major burn model. Forty-eight male Sprague-Dawley rats were divided into six groups: S group (sham/observation during 7 days after injury); SA group (sham/acupuncture/observation during 7 days after injury); B1 group (burns/observation during 1h after injury); BA1 group (burns/acupuncture/observation during 1 h after injury); B7 group (burns/observation during 7 days after injury); and BA7 group (burns/acupuncture/observation during 7 days after injury). Pain and distress scores were evaluated throughout the study. The amounts of neutrophils and mononuclear cells were evaluated semiquantitatively, and the number of microvessels was evaluated quantitatively. Our data indicated that the average pain score of BA7 group was significantly lower than the other study groups. Histopathologic investigations indicate that the amounts of neutrophil and mononuclear cell and numbers of microvessels in the unburned skin were higher in acupuncture-applied groups. The number of microvessels in burn wounds of BA7 group was significantly higher than that of the other groups. Our data suggest that acupuncture provides low pain and distress scores in experimental rat model, and it contributes to wound healing with an enhanced angiogenesis during the acute phase of burns. Future clinical and experimental studies should be conducted to discern the benefits from acupuncture in pain management of burn patients. Copyright © 2014 Elsevier Ltd and ISBI. All rights reserved.

Oxygen Gradients in the Microcirculation

PubMed Central

Pittman, Roland N.

2010-01-01

Early in the last century August Krogh embarked on a series of seminal studies to understand the connection between tissue metabolism and mechanisms by which the cardiovascular system supplied oxygen to meet those needs. Krogh recognized that oxygen was supplied from blood to the tissues by passive diffusion and that the most likely site for oxygen exchange was the capillary network. Studies of tissue oxygen consumption and diffusion coefficient, coupled with anatomical studies of capillarity in various tissues, led him to formulate a model of oxygen diffusion from a single capillary. Fifty years after the publication of this work, new methods were developed which allowed the direct measurement of oxygen in and around microvessels. These direct measurements have confirmed the predictions by Krogh and have led to extensions of his ideas resulting in our current understanding of oxygenation within the microcirculation. Developments during the last 40 years are reviewed, including studies of oxygen gradients in arterioles, capillaries, venules, microvessel wall and surrounding tissue. These measurements were made possible by the development and use of new methods to investigate oxygen in the microcirculation, so mention is made of oxygen microelectrodes, microspectrophotometry of haemoglobin and phosphorescence quenching microscopy. Our understanding of oxygen transport from the perspective of the microcirculation has gone from a consideration of oxygen gradients in capillaries and tissue to the realization that oxygen has the ability to diffuse from any microvessel to another location under the conditions that there exists a large enough PO2 gradient and that the permeability for oxygen along the intervening pathway is sufficient. PMID:21281453

Mediastinal micro-vessels clipping during lymph node dissection may contribute to reduce postoperative pleural drainage

PubMed Central

Yan, Shi; Wang, Xing; Lv, Chao; Phan, Kevin; Wang, Yuzhao; Wang, Jia; Yang, Yue

2016-01-01

Background Postoperative pleural drainage markedly influences the length of postoperative stay and financial costs of medical care. The aim of this study is to retrospectively investigate potentially predisposing factors related to pleural drainage after curative thoracic surgery and to explore the impact of mediastinal micro-vessels clipping on pleural drainage control after lymph node dissection. Methods From February 2012 to November 2013, 322 consecutive cases of operable non-small cell lung cancers (NSCLC) undergoing lobectomy and mediastinal lymph node dissection with or without application of clipping were collected. Total and daily postoperative pleural drainage were recorded. Propensity score matching (1:2) was applied to balance variables potentially impacting pleural drainage between group clip and group control. Analyses were performed to compare drainage volume, duration of chest tube and postoperative hospital stay between the two groups. Variables linked with pleural drainage in whole cohort were assessed using multivariable logistic regression analysis. Results Propensity score matching resulted in 197 patients (matched cohort). Baseline patient characteristics were matched between two groups. Group clip showed less cumulative drainage volume (P=0.020), shorter duration of chest tube (P=0.031) and postoperative hospital stay (P=0.022) compared with group control. Risk factors significantly associated with high-output drainage in multivariable logistic regression analysis were being male, age >60 years, bilobectomy/sleeve lobectomy, pleural adhesion, the application of clip applier, duration of operation ≥220 minutes and chylothorax (P<0.05). Conclusions This study suggests that mediastinal micro-vessels clipping during lymph node dissection may reduce postoperative pleural drainage and thus shorten hospital stay. PMID:27076936

Photodynamic therapy with simultaneous suppression of multiple treatment escape pathways (Conference Presentation)

NASA Astrophysics Data System (ADS)

Spring, Bryan Q.; Sears, R. Bryan; Zheng, Lei Z.; Mai, Zhiming; Watanabe, Reika; Sherwood, Margaret E.; Schoenfeld, David A.; Pogue, Brian W.; Pereira, Stephen P.; Villa, Elizabeth; Hasan, Tayyaba

2016-03-01

We introduce photoactivatable multi-inhibitor nanoliposomes (PMILs) for photodynamic tumor cell and microvessel damage in synchrony with photo-initiation of tumor-confined, multikinase inhibitor release. The PMIL is a biodegradable delivery system comprised of a nanoliposome carrying a photoactivable chromophore (benzoporphyrin derivative monoacid A, BPD) in its bilayer. A multikinase inhibitor-loaded PEG-PLGA nanoparticle is encapsulated within the liposome, which acts a barrier to nanoparticle erosion and drug release. Following intravenous PMIL administration, near infrared irradiation of tumors triggers photodynamic therapy and initiates tumor-confined drug release from the nanoparticle. This talk presents promising preclinical data in mouse models of pancreatic cancer utilizing this concept to suppress the VEGF and MET signaling pathways—both critical to cancer progression, metastasis and treatment escape. A single PMIL treatment using low doses of a multikanse inhibitor (cabozantinib, XL184) achieves sustained tumor reduction and suppresses metastatic escape, whereas combination therapy by co-administration of the individual agents has significantly reduced efficacy. The PMIL concept is amenable to a number of molecular inhibitors and offers new prospects for spatiotemporal synchronization of combination therapies whilst reducing systemic drug exposure and associated toxicities.

Stroke and the Cell Therapy Saga: Towards a Safe, Swift and Efficient Utilization of cells.

PubMed

Kubis, Nathalie

2017-01-01

The first clinical trials of cell therapy in stroke were first published in the 2000s and consisted of neural stems cells transplanted via the intracerebral pathway. Since mesenchymal stem cells showed similar capacities to differentiate into neural cells and allowed autologous cell transplantation, they were then preferentially studied, including diabetes and hypertension. More recently, bone marrow derived mononuclear cells were successfully transplanted in stroke with no need of culture processing, and simple collection by density gradient centrifugation rendering them immediately ready for use. They improve post-stroke neurological deficit in rodents and clinical trials have shown the feasibility of intra-arterial or intravenous administration. The underlying mechanisms are not yet understood. We investigated the therapeutic potential of peripheral blood derived mononuclear cells (PB-MNC) harvested from diabetic patients and stimulated by ephrin-B2 (PB-MNC+). We showed that intravenously injected PB-MNC+ after cerebral ischemia reduced infarct volume at day 3, increased cell proliferation in the peri-infarct area and the subventricular zone, decreased microglial cell density, and upregulated TGF-β expression. At D14, microvessel density was increased and functional recovery enhanced, whereas plasma levels of BDNF were increased in treated mice. Ephrin-B2 induced phenotype switching of PB-MNC by upregulating genes controlling cell proliferation, inflammation and angiogenesis, as confirmed by adhesion and Matrigel assays. PB-MNC+ transplantation in stroke is a promising approach and should be investigated for the development of rapid, non-invasive bedside cell therapy strategies in stroke.(Presented at the 1944th Meeting, July 19, 2017).

Development of photoacoustic imaging technology overlaid on ultrasound imaging and its clinical application

NASA Astrophysics Data System (ADS)

Ishihara, Miya; Tsujita, Kazuhiro; Horiguchi, Akio; Irisawa, Kaku; Komatsu, Tomohiro; Ayaori, Makoto; Hirasawa, Takeshi; Kasamatsu, Tadashi; Hirota, Kazuhiro; Tsuda, Hitoshi; Ikewaki, Katsunori; Asano, Tomohiko

2015-03-01

Purpose: Photoacoustic imaging (PAI) enables one to visualize the distribution of hemoglobin and acquire a map of microvessels without using contrast agents. The purpose of our study is to develop a clinically applicable PAI system integrated with a clinical ultrasound (US) array system with handheld PAI probes providing coregistered PAI and US images. Clinical research trials were performed to evaluate the performance and feasibility of clinical value. Materials and Methods: We developed two types of handheld PAI probes: a linear PAI probe combining a conventional linear-array US probe with optical illumination and a transrectal ultrasonography (TRUS)-type PAI probe. We performed experiments with Japanese white rabbits and conducted clinical research trials of urology and vascular medicine with the approval of the medical human ethics committee of the National Defense Medical College. Results: We successfully acquired high-dynamic-range images of the vascular network ranging from capillaries to landmark arteries and identified the femoral vein, deep femoral vein, and great saphenous vein of rabbits. These major vessels in the rabbits groin are surrounded with microvessels connected to each other. Periprostatic microvessels were monitored during radical prostatectomy for localized prostate cancer and they were colocalized with nerve fibers, and their distribution was consistent with the corresponding PAI. The TRUS-type PAI probe clearly demonstrated the location and extent of the neurovascular bundle (NVB) better than does TRUS alone. Conclusions: The system, which can obtain a PAI, a US image, and a merged image, was innovatively designed so that medical doctors can easily find the location without any prior knowledge or extended skills to analyze the obtained images. Our pilot feasibility study confirms that PAI could be an imaging modality useful in the screening study and diagnostic biopsy.

Critical role of TRPP2 and TRPC1 channels in stretch-induced injury of blood-brain barrier endothelial cells.

PubMed

Berrout, Jonathan; Jin, Min; O'Neil, Roger G

2012-02-03

The microvessels of the brain are very sensitive to mechanical stresses such as observed in traumatic brain injury (TBI). Such stresses can quickly lead to dysfunction of the microvessel endothelial cells, including disruption of blood-brain barrier (BBB). It is now evident that elevation of cytosolic calcium levels ([Ca2+]i) can compromise the BBB integrity, however the mechanism by which mechanical injury can produce a [Ca2+]i increase in brain endothelial cells is unclear. To assess the effects of mechanical/stretch injury on [Ca2+]i signaling, mouse brain microvessel endothelial cells (bEnd3) were grown to confluency on elasticized membranes and [Ca2+]i monitored using fura 2 fluorescence imaging. Application of an injury, using a pressure/stretch pulse of 50 ms, induced a rapid transient increase in [Ca2+]i. In the absence of extracellular Ca2+, the injury-induced [Ca2+]i transient was greatly reduced, but not fully eliminated, while unloading of Ca2+ stores by thapsigargin treatment in the absence of extracellular Ca2+ abolished the injury transient. Application of LOE-908 and amiloride, TRPC and TRPP2 channel blockers, respectively, both reduced the transient [Ca2+]i increase. Further, siRNA knockdown assays directed at TRPC1 and TRPP2 expression also resulted in a reduction of the injury-induced [Ca2+]i response. In addition, stretch injury induced increases of NO production and actin stress fiber formation, both of which were markedly reduced upon treatment with LOE908 and/or amiloride. We conclude that mechanical injury of brain endothelial cells induces a rapid influx of calcium, mediated by TRPC1 and TRPP2 channels, which leads to NO synthesis and actin cytoskeletal rearrangement. Copyright © 2011. Published by Elsevier B.V.

Increased lymphocyte trafficking to colonic microvessels is dependent on MAdCAM-1 and C-C chemokine mLARC/CCL20 in DSS-induced mice colitis.

PubMed

Teramoto, K; Miura, S; Tsuzuki, Y; Hokari, R; Watanabe, C; Inamura, T; Ogawa, T; Hosoe, N; Nagata, H; Ishii, H; Hibi, T

2005-03-01

Although enhanced lymphocyte trafficking is associated with colitis formation, little information about its regulation is available. The aim of this study was to examine how the murine liver and activation-regulated chemokine (mLARC/CCL20) contributes to lymphocyte recruitment in concert with vascular adhesion molecules in murine chronic experimental colitis. T and B lymphocytes isolated from the spleen were fluorescence-labelled and administered to recipient mice. Lymphocyte adhesion to microvessels of the colonic mucosa and submucosa was observed with an intravital microscope. To induce colitis, the mice received two cycles of treatment with 2% dextran sodium sulphate (DSS). In some of the experiments antibodies against the adhesion molecules or anti-mLARC/CCL20 were administered, or CC chemokine receptor 6 (CCR6) of the lymphocytes was desensitized with excess amounts of mLARC/CCL20. Significant increases in T and B cell adhesion to the microvessels of the DSS-treated mucosa and submucosa were observed. In chronic colitis, the accumulation of lymphocytes was significantly inhibited by anti-mucosal addressin cell adhesion molecule (MAdCAM)-1 mAb, but not by anti-vascular cell adhesion molecule-1. In DSS-treated colonic tissue, the expression of mLARC/CCL20 was significantly increased, the blocking of mLARC/CCL20 by monoclonal antibody or the desensitization of CCR6 with mLARC/CCL20 significantly attenuated the DSS-induced T and B cell accumulation. However, the combination of blocking CCR6 with MAdCAM-1 did not further inhibit these accumulations. These results suggest that in chronic DSS-induced colitis, both MAdCAM-1 and mLARC/CCL20 may play important roles in T and B lymphocyte adhesion in the inflamed colon under flow conditions.

[Effects of electromagnetic pulse on blood-brain barrier permeability and tight junction proteins in rats].

PubMed

Qiu, Lian-bo; Ding, Gui-rong; Zhang, Ya-mei; Zhou, Yan; Wang, Xiao-wu; Li, Kang-chu; Xu, Sheng-long; Tan, Juan; Zhou, Jia-xing; Guo, Guo-zhen

2009-09-01

To study the effect of electromagnetic pulse (EMP) on the permeability of blood-brain barrier, tight junction (TJ)-associated protein expression and localization in rats. 66 male SD rats, weighing (200 approximately 250) g, were sham or whole-body exposed to EMP at 200 kV/m for 200 pulses. The repetition rate was 1 Hz. The permeability of the blood-brain barrier in rats was assessed by albumin immunohistochemistry. The expression of typical tight junction protein ZO-1 and occludin in both cerebral cortex homogenate and cerebral cortex microvessel homogenate was analyzed by the Western blotting and the distribution of ZO-1 and occludin was examined by immunofluorescence microscopy. In the sham exposure rats, no brain capillaries showed albumin leakage, at 0.5 h after 200 kV/m EMP exposure for 200 pulses; a few brain capillaries with extravasated serum albumin was found, with the time extended, the number of brain capillaries with extravasated serum albumin increased, and reached the peak at 3 h, then began to recover at 6 h. In addition, no change in the distribution of the occludin was found after EMP exposure. Total occludin expression had no significant change compared with the control. However, the expression level of ZO-1 significantly decreased at 1 h and 3 h after EMP exposure in both cerebral cortex homogenate and cerebral cortex microvessel homogenate. Furthermore, immunofluorescence studies also showed alterations in ZO-1 protein localization in cerebral cortex microvessel. The EMP exposure (200 kV/m, 200 pulses) could increase blood-brain barrier permeability in rat, and this change is associated with specific alterations in tight junction protein ZO-1.

Prestroke Proteomic Changes in Cerebral Microvessels in Stroke-Prone, Transgenic[hCETP]-Hyperlipidemic, Dahl Salt-Sensitive Hypertensive Rats

PubMed Central

Bergerat, Agnes; Decano, Julius; Wu, Chang-Jiun; Choi, Hyungwon; Nesvizhskii, Alexey I; Moran, Ann Marie; Ruiz-Opazo, Nelson; Steffen, Martin; Herrera, Victoria LM

2011-01-01

Stroke is the third leading cause of death in the United States with high rates of morbidity among survivors. The search to fill the unequivocal need for new therapeutic approaches would benefit from unbiased proteomic analyses of animal models of spontaneous stroke in the prestroke stage. Since brain microvessels play key roles in neurovascular coupling, we investigated prestroke microvascular proteome changes. Proteomic analysis of cerebral cortical microvessels (cMVs) was done by tandem mass spectrometry comparing two prestroke time points. Metaprotein-pathway analyses of proteomic spectral count data were done to identify risk factor–induced changes, followed by QSPEC-analyses of individual protein changes associated with increased stroke susceptibility. We report 26 cMV proteome profiles from male and female stroke-prone and non–stroke-prone rats at 2 months and 4.5 months of age prior to overt stroke events. We identified 1,934 proteins by two or more peptides. Metaprotein pathway analysis detected age-associated changes in energy metabolism and cell-to-microenvironment interactions, as well as sex-specific changes in energy metabolism and endothelial leukocyte transmigration pathways. Stroke susceptibility was associated independently with multiple protein changes associated with ischemia, angiogenesis or involved in blood brain barrier (BBB) integrity. Immunohistochemical analysis confirmed aquaporin-4 and laminin-α1 induction in cMVs, representative of proteomic changes with >65 Bayes factor (BF), associated with stroke susceptibility. Altogether, proteomic analysis demonstrates significant molecular changes in ischemic cerebral microvasculature in the prestroke stage, which could contribute to the observed model phenotype of microhemorrhages and postischemic hemorrhagic transformation. These pathways comprise putative targets for translational research of much needed novel diagnostic and therapeutic approaches for stroke. PMID:21519634

Mitochondria Are Critical for BDNF-Mediated Synaptic and Vascular Plasticity of Hippocampus following Repeated Electroconvulsive Seizures.

PubMed

Chen, Fenghua; Ardalan, Maryam; Elfving, Betina; Wegener, Gregers; Madsen, Torsten M; Nyengaard, Jens R

2018-03-01

Electroconvulsive therapy is a fast-acting and efficient treatment of depression used in the clinic. The underlying mechanism of its therapeutic effect is still unclear. However, recovery of synaptic connections and synaptic remodeling is thought to play a critical role for the clinical efficacy obtained from a rapid antidepressant response. Here, we investigated the relationship between synaptic changes and concomitant nonneuronal changes in microvasculature and mitochondria and its relationship to brain-derived neurotrophic factor level changes after repeated electroconvulsive seizures, an animal model of electroconvulsive therapy. Electroconvulsive seizures or sham treatment was given daily for 10 days to rats displaying a genetically driven phenotype modelling clinical depression: the Flinders Sensitive and Resistant Line rats. Stereological principles were employed to quantify numbers of synapses and mitochondria, and the length of microvessels in the hippocampus. The brain-derived neurotrophic factor protein levels were quantified with immunohistochemistry. In untreated controls, a lower number of synapses and mitochondria was accompanied by shorter microvessels of the hippocampus in "depressive" phenotype (Flinders Sensitive Line) compared with the "nondepressed" phenotype (Flinders Resistant Line). Electroconvulsive seizure administration significantly increased the number of synapses and mitochondria, and length of microvessels both in Flinders Sensitive Line-electroconvulsive seizures and Flinders Resistant Line-electroconvulsive seizures rats. In addition, the amount of brain-derived neurotrophic factor protein was significantly increased in Flinders Sensitive Line and Flinders Resistant Line rats after electroconvulsive seizures. Furthermore, there was a significant positive correlation between brain-derived neurotrophic factor level and mitochondria/synapses. Our results indicate that rapid and efficient therapeutic effect of electroconvulsive seizures may be related to synaptic plasticity, accompanied by brain-derived neurotrophic factor protein level elevation and mitochondrial and vascular support. © The Author(s) 2017. Published by Oxford University Press on behalf of CINP.

Deregulation of tumor angiogenesis and blockade of tumor growth in PPARβ-deficient mice

PubMed Central

Müller-Brüsselbach, Sabine; Kömhoff, Martin; Rieck, Markus; Meissner, Wolfgang; Kaddatz, Kerstin; Adamkiewicz, Jürgen; Keil, Boris; Klose, Klaus J; Moll, Roland; Burdick, Andrew D; Peters, Jeffrey M; Müller, Rolf

2007-01-01

The peroxisome proliferator-activated receptor-β (PPARβ) has been implicated in tumorigenesis, but its precise role remains unclear. Here, we show that the growth of syngeneic Pparb wild-type tumors is impaired in Pparb−/− mice, concomitant with a diminished blood flow and an abundance of hyperplastic microvascular structures. Matrigel plugs containing pro-angiogenic growth factors harbor increased numbers of morphologically immature, proliferating endothelial cells in Pparb−/− mice, and retroviral transduction of Pparb triggers microvessel maturation. We have identified the Cdkn1c gene encoding the cell cycle inhibitor p57Kip2 as a PPARβ target gene and a mediator of the PPARβ-mediated inhibition of cell proliferation, which provides a possible mechanistic explanation for the observed tumor endothelial hyperplasia and deregulation of tumor angiogenesis in Pparb−/− mice. Our data point to an unexpected essential role for PPARβ in constraining tumor endothelial cell proliferation to allow for the formation of functional tumor microvessels. PMID:17641685

The neurovascular unit, matrix proteases, and innate inflammation.

PubMed

del Zoppo, Gregory J

2010-10-01

In the central nervous system, microvessel-neuron interactions appear highly coordinated. The rapid simultaneous responses of the microvasculature, neurons, and glia to focal ischemia in experimental ischemic stroke suggest that these responses could be viewed in a unitary fashion, rather than as individual components. The "neurovascular unit" consists of microvessels (endothelial cells-basal lamina matrix-astrocyte end-feet [and pericytes]), astrocytes, neurons and their axons, and other supporting cells that are likely to modulate the function of the "unit." Each cell component generates an inflammatory response to ischemia. Matrix metalloproteinase (MMP)-9 was first associated with hemorrhagic transformation following focal ischemia in an experimental model. A series of studies of ischemic stroke patients also suggests a relationship between MMP-9 levels and several consequences of ischemic injury, including hemorrhagic transformation. Recent experimental work suggests specific cell sources for MMP-9 generation and for matrix proteases from four distinct families that could impact neurovascular unit integrity. © 2010 New York Academy of Sciences.

The role of protein kinase C in the opening of blood-brain barrier induced by electromagnetic pulse.

PubMed

Qiu, Lian-Bo; Ding, Gui-Rong; Li, Kang-Chu; Wang, Xiao-Wu; Zhou, Yan; Zhou, Yong-Chun; Li, Yu-Rong; Guo, Guo-Zhen

2010-06-29

The aim of this study was to determine the role of protein kinase C signaling in electromagnetic pulse (EMP)-induced blood-brain barrier (BBB) permeability change in rats. The protein level of total PKC and two PKC isoforms (PKC-alpha, and PKC-beta II) were determined in brain cerebral cortex microvessels by Western blot after exposing rats to EMP at 200kV/m for 200 pulses with 1Hz repetition rate. It was found that the protein level of PKC and PKC-betaII (but not PKC-alpha) in cerebral cortex microvessels increased significantly at 0.5h and 1h after EMP exposure compared with sham-exposed animals and then recovered at 3h. A specific PKC antagonist (H7) almost blocked EMP-induced BBB permeability change. EMP-induced BBB tight junction protein ZO-1 translocation was also inhibited. Our data indicated that PKC signaling was involved in EMP-induced BBB permeability change and ZO-1 translocation in rat.

Two-Photon Imaging of Cortical Surface Microvessels Reveals a Robust Redistribution in Blood Flow after Vascular Occlusion

PubMed Central

Schaffer, Chris B; Friedman, Beth; Nishimura, Nozomi; Schroeder, Lee F; Tsai, Philbert S; Ebner, Ford F; Lyden, Patrick D

2006-01-01

A highly interconnected network of arterioles overlies mammalian cortex to route blood to the cortical mantle. Here we test if this angioarchitecture can ensure that the supply of blood is redistributed after vascular occlusion. We use rodent parietal cortex as a model system and image the flow of red blood cells in individual microvessels. Changes in flow are quantified in response to photothrombotic occlusions to individual pial arterioles as well as to physical occlusions of the middle cerebral artery (MCA), the primary source of blood to this network. We observe that perfusion is rapidly reestablished at the first branch downstream from a photothrombotic occlusion through a reversal in flow in one vessel. More distal downstream arterioles also show reversals in flow. Further, occlusion of the MCA leads to reversals in flow through approximately half of the downstream but distant arterioles. Thus the cortical arteriolar network supports collateral flow that may mitigate the effects of vessel obstruction, as may occur secondary to neurovascular pathology. PMID:16379497

Reciprocal coupling of coagulation and innate immunity via neutrophil serine proteases.

PubMed

Massberg, Steffen; Grahl, Lenka; von Bruehl, Marie-Luise; Manukyan, Davit; Pfeiler, Susanne; Goosmann, Christian; Brinkmann, Volker; Lorenz, Michael; Bidzhekov, Kiril; Khandagale, Avinash B; Konrad, Ildiko; Kennerknecht, Elisabeth; Reges, Katja; Holdenrieder, Stefan; Braun, Siegmund; Reinhardt, Christoph; Spannagl, Michael; Preissner, Klaus T; Engelmann, Bernd

2010-08-01

Blood neutrophils provide the first line of defense against pathogens but have also been implicated in thrombotic processes. This dual function of neutrophils could reflect an evolutionarily conserved association between blood coagulation and antimicrobial defense, although the molecular determinants and in vivo significance of this association remain unclear. Here we show that major microbicidal effectors of neutrophils, the serine proteases neutrophil elastase and cathepsin G, together with externalized nucleosomes, promote coagulation and intravascular thrombus growth in vivo. The serine proteases and extracellular nucleosomes enhance tissue factor- and factor XII-dependent coagulation in a process involving local proteolysis of the coagulation suppressor tissue factor pathway inhibitor. During systemic infection, activation of coagulation fosters compartmentalization of bacteria in liver microvessels and reduces bacterial invasion into tissue. In the absence of a pathogen challenge, neutrophil-derived serine proteases and nucleosomes can contribute to large-vessel thrombosis, the main trigger of myocardial infarction and stroke. The ability of coagulation to suppress pathogen dissemination indicates that microvessel thrombosis represents a physiological tool of host defense.

Sprouting angiogenesis in human midterm uterus and fallopian tube is guided by endothelial tip cells.

PubMed

Rusu, M C; Motoc, A G M; Pop, F; Folescu, R

2013-01-01

Five samples of human midterm fetal uterus and fallopian tube (four donor bodies) were used to assess whether or not processes of angiogenesis are guided by endothelial tip cells (ETCs), and if cytokine-receptors, such as CD117/c-kit and PDGFR-α, are expressed in the microenvironment of the endothelial tubes. CD34 labeled microvessels in the uterine wall (myometrium and endometrium) and in the wall of the uterine (fallopian) tube, and accurately identified ETCs in both organs. We conclude that sprouting angiogenesis in the developing human female tract is guided by ETCs. Moreover, CD117/c-kit antibodies labeled mural networks of pericytes, α-SMA-positive and desmin-negative, related to the endometrial (but not myometrial) microvessels, and similar labeling was identified in the wall of the uterine tube. PDGFR-α positive labeling, stromal and pericytary, was also found. Thus, sprouting angiogenesis in human fetal genital organs appears to be guided by tip cells and is influenced by tyrosine kinase receptor signaling.

Review of photorejuvenation: devices, cosmeceuticals, or both?

PubMed

Rokhsar, Cameron K; Lee, Sandra; Fitzpatrick, Richard E

2005-09-01

Both the public and the medical profession have placed a lot of attention on reversal of signs of aging and photodamage, resulting in numerous cosmeceutical products and nonablative laser techniques designed to achieve these results. The purpose of this report is to briefly review both the cosmeceutical products and nonablative laser techniques that appear to be most promising based on published studies. After this review, recommendations for potential enhancement of benefits by combining cosmeceuticals and laser treatments will be explored. Pulsed dye lasers targeting microvessels, intense pulsed light targeting both melanin and microvessels, and midinfrared lasers targeting dermal water and collagen all appear to have some ability to improve skin texture, color, and wrinkling. Retinoids, vitamin C, alpha-hydroxy acids, and topical growth factors may also stimulate repair mechanisms that result in similar improvements in photodamaged skin. Although supported only by theoretic considerations and anecdotal reports, it seems logical that the concurrent use of appropriate cosmeceuticals with nonablative laser photorejuvenation should result in enhanced benefits.

An investigation into the blood-flow characteristics of telangiectatic skin lesions in systemic sclerosis using dual-wavelength laser Doppler imaging.

PubMed

Murray, A K; Moore, T L; Griffiths, C E M; Herrick, A L

2009-07-01

Superficial telangiectases associated with systemic sclerosis may be more responsive to treatment than those deeper in the dermis. We investigated whether dual-wavelength laser Doppler imaging (LDI) is sufficiently sensitive to ascertain the distribution of blood flow within telangiectases and whether blood flow relates to telangiectatic diameter. The perfusion and diameter of 20 telangiectases were measured in superficial and deeper layers of the skin using dual-wavelength LDI. Of 20 telangiectases, 18 had higher blood flow in the red (representing deeper blood flow), rather than the green (representing superficial blood flow) wavelength images. Clinically apparent diameters correlated with those of the superficial (r = 0.61, P = 0.01), but not with the deeper blood flow images. Hence, the apparent size of telangiectases at the skin surface does not predict blood flow through the microvessel(s) at deeper levels, and thus clinically apparent size is unlikely to predict treatment response. Dual-wavelength LDI may help predict treatment response.

Deformation and dynamics of red blood cells in flow through cylindrical microchannels.

PubMed

Fedosov, Dmitry A; Peltomäki, Matti; Gompper, Gerhard

2014-06-28

The motion of red blood cells (RBCs) in microcirculation plays an important role in blood flow resistance and in the cell partitioning within a microvascular network. Different shapes and dynamics of RBCs in microvessels have been previously observed experimentally including the parachute and slipper shapes. We employ mesoscale hydrodynamic simulations to predict the phase diagram of shapes and dynamics of RBCs in cylindrical microchannels, which serve as idealized microvessels, for a wide range of channel confinements and flow rates. A rich dynamical behavior is found, with snaking and tumbling discocytes, slippers performing a swinging motion, and stationary parachutes. We discuss the effects of different RBC states on the flow resistance, and the influence of RBC properties, characterized by the Föppl-von Kármán number, on the shape diagram. The simulations are performed using the same viscosity for both external and internal fluids surrounding a RBC; however, we discuss how the viscosity contrast would affect the shape diagram.

Liposuction Preserves the Morphological Integrity of the Microvascular Network: Flow Cytometry and Confocal Microscopy Evidence in a Controlled Study.

PubMed

Bertheuil, Nicolas; Chaput, Benoit; Berger-Müller, Sandra; Ménard, Cédric; Mourcin, Frédéric; Watier, Eric; Grolleau, Jean-Louis; Garrido, Ignacio; Tarte, Karin; Sensébé, Luc; Varin, Audrey

2016-05-01

Liposuction is a very popular technique in plastic surgery that allows for the taking adipose tissue (AT) on large surfaces with little risk of morbidity. Although liposuction was previously shown to preserve large perforator vessels, little is known about the effects of liposuction on the microvasculature network. The aim of this study was to analyze the effect of liposuction on the preservation of microvessels at tissue and cellular levels by flow cytometry and confocal microscopy following abdominoplasty procedure. Percentage of endothelial cells in AT from liposuction and en bloc AT was determined by multicolor flow cytometry. Moreover, vessel density and adipocyte content were analyzed in situ in 3 different types of AT (en bloc, from liposuction, and residual AT after liposuction) by confocal microscopy. Flow cytometric analysis showed that en bloc AT contained 30.6% ± 12.9% and AT from liposuction 21.6% ± 9.9% of endothelial cells (CD31(pos)/CD45(neg)/CD235a(neg)/CD11b(neg)) (P = .009). Moreover, analysis of paired AT from the same patients (n = 5) confirmed a lower percentage of endothelial cells in AT from liposuction compared to en bloc AT (17.7% ± 4.5% vs 21.9% ± 3.3%, P = .031). Likewise, confocal microscopy showed that en bloc AT contained 8.2% ± 6.3%, AT from liposuction only 1.6% ± 1.0% (P < .0001), and AT after liposuction 8.9% ± 4.1% (P = .111) of CD31(pos) vessels. Conversely, adipocyte content was 39.5% ± 14.5% in the en bloc AT, 45% ± 18.4% in AT from liposuction (P = .390), and 18.8 ± 14.8% in AT after liposuction (P = .011). For the first time, we demonstrate that liposuction preserves the microvascular network. Indeed, a low percentage of endothelial cells was found in AT from liposuction and we confirm the persistence of microvessels in the tissue after liposuction. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

HULC long noncoding RNA silencing suppresses angiogenesis by regulating ESM-1 via the PI3K/Akt/mTOR signaling pathway in human gliomas.

PubMed

Zhu, Yu; Zhang, Xuebin; Qi, Lisha; Cai, Ying; Yang, Ping; Xuan, Geng; Jiang, Yuan

2016-03-22

Tumor angiogenesis plays a critical role in the tumor progression. Highly upregulated in liver cancer (HULC) is a long noncoding RNA (lncRNA) that acts as an oncogene in gliomas. We found that HULC, vascular endothelial growth factor (VEGF), and ESM-1 (endothelial cell specific molecule 1) expression and microvessel density were positively correlated with grade dependency in glioma patient tissues, and that HULC silencing suppressed angiogenesis by inhibiting glioma cells proliferation and invasion. This process induced anoikis and blocked the cell cycle at G1/S phase via the PI3K/Akt/mTOR signaling pathway, thus regulating the tumor-related genes involved in the above biological behavior in human glioma U87MG and U251 cells. However, these effects were reversed by ESM-1 overexpression, suggesting a mediating role of ESM-1 in the pro-angiogenesis effect of HULC. Our results define the mechanism of the pro-angiogenesis activity of HULC, which shows potential for application as a therapeutic target in glioma.

Pigment epithelium derived factor inhibits the growth of human endometrial implants in nude mice and of ovarian endometriotic stromal cells in vitro.

PubMed

Sun, Yanmei; Che, Xuan; Zhu, Libo; Zhao, Mengdan; Fu, Guofang; Huang, Xiufeng; Xu, Hong; Hu, Fuqiang; Zhang, Xinmei

2012-01-01

Angiogenesis is a prerequisite for the formation and development of endometriosis. Pigment epithelium derived factor (PEDF) is a natural inhibitor of angiogenesis. We previously demonstrated a reduction of PEDF in the peritoneal fluid, serum and endometriotic lesions from women with endometriosis compared with women without endometriosis. Here, we aim to investigate the inhibitory effect of PEDF on human endometriotic cells in vivo and in vitro. We found that PEDF markedly inhibited the growth of human endometrial implants in nude mice and of ovarian endometriotic stromal cells in vitro by up-regulating PEDF expression and down-regulating vascular endothelial growth factor (VEGF) expression. Moreover, apoptotic index was significantly increased in endometriotic lesions in vivo and endometriotic stromal cells in vitro when treated with PEDF. In mice treated with PEDF, decreased microvessel density labeled by Von Willebrand factor but not by α-Smooth Muscle Actin was observed in endometriotic lesions. And it showed no increase in PEDF expression of the ovary and uterus tissues. These findings suggest that PEDF gene therapy may be a new treatment for endometriosis.

Decreased expression of class III β-tubulin is associated with unfavourable prognosis in patients with malignant melanoma.

PubMed

Shimizu, Akira; Kaira, Kyoichi; Yasuda, Masahito; Asao, Takayuki; Ishikawa, Osamu

2016-02-01

Class III β-tubulin (TUBB3) has been recognized as being associated with resistance to taxane-based regimens in several cancers. However, little is known about the clinicopathological significance of TUBB3 expression in patients with cutaneous malignant melanoma. The aim of this study was to examine the prognostic significance of TUBB3 expression in cutaneous malignant melanoma. A total of 106 patients with surgically resected cutaneous malignant melanoma were assessed. Tumour sections were immunohistochemically stained for TUBB3, Ki-67 and microvessel density with CD34. TUBB3 was highly expressed in 80% (85/106) of patients. No statistically significant relationship was observed between the high expression of TUBB3 and any variables. On univariate analysis, ulceration, disease stage, TUBB3 and CD34 revealed a significant relationship with overall survival and progression-free survival. Multivariate analysis confirmed that a low TUBB3 expression was an independent prognostic factor for poor prognosis of cutaneous malignant melanoma. The decreased expression of TUBB3 could be a significant marker for predicting unfavourable prognosis in patients with cutaneous malignant melanoma.

Effects of low-dose cyclophosphamide with piroxicam on tumour neovascularization in a canine oral malignant melanoma-xenografted mouse model.

PubMed

Choisunirachon, N; Jaroensong, T; Yoshida, K; Saeki, K; Mochizuki, M; Nishimura, R; Sasaki, N; Nakagawa, T

2015-12-01

Low-dose cyclophosphamide (CyLD) has shown promise in the treatment of several cancers; however, the effect of CyLD on canine oral malignant melanoma has never been explored. In this study, we investigated the effects of CyLD with or without piroxicam (Px) on tumour neovascularization and vascular normalization in a canine oral malignant melanoma-xenografted mice model. After treatment with CyLD, Px or a combination of both (CyPx), the growth of the tumour in the treatment groups was significantly suppressed compared to the control group at 30 days of treatment. Proliferation index was also significantly reduced by all treatments, only CyPx significantly lowered microvessel density and vascular endothelial growth factor (VEGF) levels. Additionally, CyLD significantly reduced the proportion of normal vessels and caused an imbalance between VEGF and thrombospondin-1. These results suggested that CyPx has potent anti-angiogenic effects in terms of both the number and quality of blood vessels in xenografted canine oral malignant melanoma. © 2013 John Wiley & Sons Ltd.

Evaluation of the Wound Healing Potential of Resina Draconis (Dracaena cochinchinensis) in Animal Models.

PubMed

Liu, Huihui; Lin, Shaohui; Xiao, Dan; Zheng, Xiao; Gu, Yan; Guo, Shanyu

2013-01-01

Resina Draconis (RD) is a type of dragon's blood resin obtained from Dracaena cochinchinensis (Lour.) S.C. Chen (Yunnan, China). It has been used as a medicine since ancient times by many cultures. The ethanolic extract of Resina Draconis (RDEE) was evaluated for its wound-healing activity using excision and incision wound models in rats. Group I, the control group, was treated with ointment base. Group II, which served as a reference standard, was treated with moist exposed burn ointment (MEBO). Group III was treated with RDEE. The parameters observed were percentage of wound contraction, epithelialization period, tensile strength, histopathological studies, microvessel density (MVD), and the expression of vascular endothelial growth factor (VEGF) and transforming growth factor- β 1 (TGF- β 1). The group treated with RDEE showed significantly better wound contraction and better skin-breaking strength as compared with the control group. The results of histopathological examination, MVD, and the expression levels of growth factors supported the outcome of the wound models as well. The present study provided a scientific rationale for the traditional use of RD in the management of wounds.

Angiosonography in suspicious breast lesions with non-diagnostic FNAC: comparison with power Doppler US.

PubMed

Caumo, F; Carbognin, G; Casarin, A; Pinali, L; Vasori, S; D'Onofrio, M; Pozzi Mucelli, R

2006-02-01

The purpose of this study was to evaluate the accuracy of angiosonography in comparison with colour Doppler ultrasound (US) in the discrimination of suspicious breast lesions with nondiagnostic fine-needle aspiration cytology (FNAC). Pre-operative Power Doppler US and angiosonography were prospectively performed in 20 suspicious breast lesions with non-diagnostic FNAC. A second-generation US contrast agent was utilised with a high-frequency transducer and a contrast-specific algorithm (low acoustic pressure CnTI). The enhancement characteristics of all lesions were analysed using qualitative and quantitative parameters obtained from time-intensity curves with the different imaging modalities. The final diagnosis was confirmed at pathology in all cases. Microvessel density (MVD) was assessed in the surgical specimen using CD34. The correct assessment of biological behaviour was achieved in all cases by angiosonography (sensitivity of 100%; specificity of 91%) and colour Doppler US (45% sensitivity; 78% specificity). MVD correlated with the biological behaviour. Angiosonography is more accurate than colour Doppler US in the correct assessment of biological behaviour of suspicious breast lesions.

Direct Isolation, Culture and Transplant of Mouse Skeletal Muscle Derived Endothelial Cells with Angiogenic Potential

PubMed Central

Ieronimakis, Nicholas; Balasundaram, Gayathri; Reyes, Morayma

2008-01-01

Background Although diseases associated with microvascular endothelial dysfunction are among the most prevalent illnesses to date, currently no method exists to isolate pure endothelial cells (EC) from skeletal muscle for in vivo or in vitro study. Methodology By utilizing multicolor fluorescent-activated cell sorting (FACS), we have isolated a distinct population of Sca-1+, CD31+, CD34dim and CD45− cells from skeletal muscles of C57BL6 mice. Characterization of this population revealed these cells are functional EC that can be expanded several times in culture without losing their phenotype or capabilities to uptake acetylated low-density lipoprotein (ac-LDL), produce nitric oxide (NO) and form vascular tubes. When transplanted subcutaneously or intramuscularly into the tibialis anterior muscle, EC formed microvessels and integrated with existing vasculature. Conclusion This method, which is highly reproducible, can be used to study the biology and role of EC in diseases such as peripheral vascular disease. In addition this method allows us to isolate large quantities of skeletal muscle derived EC with potential for therapeutic angiogenic applications. PMID:18335025

Evaluation of the Wound Healing Potential of Resina Draconis (Dracaena cochinchinensis) in Animal Models

PubMed Central

Gu, Yan

2013-01-01

Resina Draconis (RD) is a type of dragon's blood resin obtained from Dracaena cochinchinensis (Lour.) S.C. Chen (Yunnan, China). It has been used as a medicine since ancient times by many cultures. The ethanolic extract of Resina Draconis (RDEE) was evaluated for its wound-healing activity using excision and incision wound models in rats. Group I, the control group, was treated with ointment base. Group II, which served as a reference standard, was treated with moist exposed burn ointment (MEBO). Group III was treated with RDEE. The parameters observed were percentage of wound contraction, epithelialization period, tensile strength, histopathological studies, microvessel density (MVD), and the expression of vascular endothelial growth factor (VEGF) and transforming growth factor-β1 (TGF-β1). The group treated with RDEE showed significantly better wound contraction and better skin-breaking strength as compared with the control group. The results of histopathological examination, MVD, and the expression levels of growth factors supported the outcome of the wound models as well. The present study provided a scientific rationale for the traditional use of RD in the management of wounds. PMID:23762154

ETS-1 Expression Is Hypoxia-independent in Glioblastoma-derived Endothelial and Mesenchymal Stem-like Cells.

PubMed

Koessinger, Dominik; Albrecht, Valerie; Faber, Florian; Jaehnert, Irene; Schichor, Christian

2018-06-01

Tumor cells infiltrating the brain are a typical hallmark of glioblastoma. Invasiveness of glioma cells has been associated with ETS proto-oncogene 1 (ETS-1). In non-glial tumors, ETS-1 expression has been linked to hypoxia. However, it is not known whether hypoxia regulates ETS-1 expression in glioblastoma. The spatial distribution of ETS-1 expression in primary glioblastoma was assessed using immunohistochemistry. ETS-1 expression in glioblastoma-derived mesenchymal stem-like cells (gbMSLCs) was determined using immunocytochemistry. The effect of hypoxia on ETS-1 expression of gbMSLCs, glioma cell lines and glioblastoma-derived endothelial cells was assessed using polymerase chain reaction and immunoblotting. Our immunohistochemical studies revealed ETS-1 expression in stromal and endothelial glioblastoma cells. Stromal ETS-1 expression in glioblastoma correlated with microvessel density. gbMSLCs were found to express ETS-1. In all examined cell lines, ETS-1 transcription and expression were independent of hypoxia. In glioblastoma, ETS-1-expression is not dependent on hypoxia, but correlates with tumor vascularization. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Cellular Model of Atherogenesis Based on Pluripotent Vascular Wall Pericytes.

PubMed

Ivanova, Ekaterina A; Orekhov, Alexander N

2016-01-01

Pericytes are pluripotent cells that can be found in the vascular wall of both microvessels and large arteries and veins. They have distinct morphology with long branching processes and form numerous contacts with each other and with endothelial cells, organizing the vascular wall cells into a three-dimensional network. Accumulating evidence demonstrates that pericytes may play a key role in the pathogenesis of vascular disorders, including atherosclerosis. Macrovascular pericytes are able to accumulate lipids and contribute to growth and vascularization of the atherosclerotic plaque. Moreover, they participate in the local inflammatory process and thrombosis, which can lead to fatal consequences. At the same time, pericytes can represent a useful model for studying the atherosclerotic process and for the development of novel therapeutic approaches. In particular, they are suitable for testing various substances' potential for decreasing lipid accumulation induced by the incubation of cells with atherogenic low-density lipoprotein. In this review we will discuss the application of cellular models for studying atherosclerosis and provide several examples of successful application of these models to drug research.

High-Accuracy Ultrasound Contrast Agent Detection Method for Diagnostic Ultrasound Imaging Systems.

PubMed

Ito, Koichi; Noro, Kazumasa; Yanagisawa, Yukari; Sakamoto, Maya; Mori, Shiro; Shiga, Kiyoto; Kodama, Tetsuya; Aoki, Takafumi

2015-12-01

An accurate method for detecting contrast agents using diagnostic ultrasound imaging systems is proposed. Contrast agents, such as microbubbles, passing through a blood vessel during ultrasound imaging are detected as blinking signals in the temporal axis, because their intensity value is constantly in motion. Ultrasound contrast agents are detected by evaluating the intensity variation of a pixel in the temporal axis. Conventional methods are based on simple subtraction of ultrasound images to detect ultrasound contrast agents. Even if the subject moves only slightly, a conventional detection method will introduce significant error. In contrast, the proposed technique employs spatiotemporal analysis of the pixel intensity variation over several frames. Experiments visualizing blood vessels in the mouse tail illustrated that the proposed method performs efficiently compared with conventional approaches. We also report that the new technique is useful for observing temporal changes in microvessel density in subiliac lymph nodes containing tumors. The results are compared with those of contrast-enhanced computed tomography. Copyright © 2015 World Federation for Ultrasound in Medicine & Biology. Published by Elsevier Inc. All rights reserved.

Monoamine oxidase A (MAO A) inhibitors decrease glioma progression.

PubMed

Kushal, Swati; Wang, Weijun; Vaikari, Vijaya Pooja; Kota, Rajesh; Chen, Kevin; Yeh, Tzu-Shao; Jhaveri, Niyati; Groshen, Susan L; Olenyuk, Bogdan Z; Chen, Thomas C; Hofman, Florence M; Shih, Jean C

2016-03-22

Glioblastoma (GBM) is an aggressive brain tumor which is currently treated with temozolomide (TMZ). Tumors usually become resistant to TMZ and recur; no effective therapy is then available. Monoamine Oxidase A (MAO A) oxidizes monoamine neurotransmitters resulting in reactive oxygen species which cause cancer. This study shows that MAO A expression is increased in human glioma tissues and cell lines. MAO A inhibitors, clorgyline or the near-infrared-dye MHI-148 conjugated to clorgyline (NMI), were cytotoxic for glioma and decreased invasion in vitro. Using the intracranial TMZ-resistant glioma model, clorgyline or NMI alone or in combination with low-dose TMZ reduced tumor growth and increased animal survival. NMI was localized specifically to the tumor. Immunocytochemistry studies showed that the MAO A inhibitor reduced proliferation, microvessel density and invasion, and increased macrophage infiltration. In conclusion, we have identified MAO A inhibitors as potential novel stand-alone drugs or as combination therapy with low dose TMZ for drug-resistant gliomas. NMI can also be used as a non-invasive imaging tool. Thus has a dual function for both therapy and diagnosis.

A photoactivable multi-inhibitor nanoliposome for tumour control and simultaneous inhibition of treatment escape pathways

NASA Astrophysics Data System (ADS)

Spring, Bryan Q.; Bryan Sears, R.; Zheng, Lei Zak; Mai, Zhiming; Watanabe, Reika; Sherwood, Margaret E.; Schoenfeld, David A.; Pogue, Brian W.; Pereira, Stephen P.; Villa, Elizabeth; Hasan, Tayyaba

2016-04-01

Nanoscale drug delivery vehicles can facilitate multimodal therapies of cancer by promoting tumour-selective drug release. However, few are effective because cancer cells develop ways to resist and evade treatment. Here, we introduce a photoactivable multi-inhibitor nanoliposome (PMIL) that imparts light-induced cytotoxicity in synchrony with a photoinitiated and sustained release of inhibitors that suppress tumour regrowth and treatment escape signalling pathways. The PMIL consists of a nanoliposome doped with a photoactivable chromophore (benzoporphyrin derivative, BPD) in the lipid bilayer, and a nanoparticle containing cabozantinib (XL184)—a multikinase inhibitor—encapsulated inside. Near-infrared tumour irradiation, following intravenous PMIL administration, triggers photodynamic damage of tumour cells and microvessels, and simultaneously initiates release of XL184 inside the tumour. A single PMIL treatment achieves prolonged tumour reduction in two mouse models and suppresses metastatic escape in an orthotopic pancreatic tumour model. The PMIL offers new prospects for cancer therapy by enabling spatiotemporal control of drug release while reducing systemic drug exposure and associated toxicities.

The Nature of Dynamic Arteriolar Vasoreactivity: A Mini-Review and A classification Scheme

DTIC Science & Technology

1993-06-08

small veins. In this videomicroscopy study we always examined a junction of a true transverse (TR) and a true terminal (TE) arteriole within the muscle...by LDF), comparisons of vascular wall behavior were made from intravital videomicroscopy records. Vasoreactive behavior of the microvessels was

Reactivity of retinal blood flow to 100% oxygen breathing after lipopolysaccharide administration in healthy subjects.

PubMed

Kolodjaschna, Julia; Berisha, Fatmire; Lasta, Michael; Polska, Elzbieta; Fuchsjäger-Mayrl, Gabriele; Schmetterer, Leopold

2008-08-01

Administration of low doses of Escherichia coli endotoxin (LPS) to humans enables the study of inflammatory mechanisms. The purpose of the present study was to investigate the retinal vascular reactivity after LPS infusion. In a randomized placebo-controlled cross-over study, 18 healthy male volunteers received 20 IU/kg LPS or placebo as an intravenous bolus infusion. Outcome parameters were measured at baseline and 4h after LPS/placebo administration. At baseline and at 4h after administration a short period of 100% oxygen inhalation was used to assess retinal vasoreactivity to this stimulus. Perimacular white blood cell velocity, density and flux were assessed with the blue-field entoptic technique, retinal branch arterial and venous diameters were measured with a retinal vessel analyzer and red blood cell velocity in retinal branch veins was measured with laser Doppler velocimetry. LPS is associated with peripheral blood leukocytosis and increased white blood cell density in ocular microvessels (p<0.001). In addition, retinal arterial (p=0.02) and venous (p<0.01) diameters were increased. All retinal hemodynamic parameters showed a decrease during 100% oxygen breathing. This decrease was significantly blunted by LPS for all retinal outcome parameters except venous diameter (p=0.04 for white blood cell velocity, p=0.0002 for white blood cell density, p<0.0001 for white blood cell flux, p=0.01 for arterial diameter, p=0.02 for red blood cell velocity and p=0.006 for red blood cell flux). These data indicate that LPS-induced inflammation induces vascular dysregulation in the retina. This may provide a link between inflammation and vascular dysregulation. Further studies are warranted to investigate whether this model may be suitable to study inflammation induced vascular dysregulation in the eye.

Human umbilical cord stem cell conditioned medium versus serum-free culture medium in the treatment of cryopreserved human ovarian tissues in in-vitro culture: a randomized controlled trial.

PubMed

Jia, Yingxian; Shi, Xiaohan; Xie, Yidong; Xie, Xiaochuan; Wang, Yan; Li, Shangwei

2017-06-24

To reduce young female fertility loss, the in-vitro culture of cryopreserved ovarian cortical tissues (OCTs) is considered an effective approach without delaying treatment and undergoing stimulation medicine. However, ischemic damage and follicular loss during the in-vitro culture of OCTs are major technical challenges. Human umbilical cord stem cells (HUMSCs) and their conditioned medium (HUMSC-CM) have been considered to be potential resources for regeneration medicine because they secrete cytokines and enhance cell survival and function. The aim of this study was to determine whether HUMSC-CM improves the development of frozen-thawed in-vitro cultured ovarian tissues compared with a serum-free culture medium (SF-CM). The thawed OCTs (n = 68) were cultivated in HUMSC-CM and SF-CM in vitro for 8 days, and the ovarian tissues were processed and analyzed by a classical histological evaluation. The microvessel density (MVD) and apotosis detection during in-vitro culture of OCTs were also performed. A significant difference in the rate of morphologically normal primordial follicles in the HUMSC-CM group was observed compared to that in the SF-CM group (group C) from days 2 to 4 (day 2: group B 58.0 ± 2.45% vs group C 32.0 ± 5.83%, p = 0.002; day 3: group B 55.5 ± 4.20% vs group C 21.0 ± 9.80%, p = 0.048; day 4: group B 52.0 ± 4.08% vs group C 21.5 ± 8.19%, p = 0.019). The microvessel density (MVD) detection showed a time-dependent increase and peaked on day 4. There was a significant difference between groups B (49.33 ± 0.58) and C (24.33 ± 3.79) (p = 0.036). The percentage of apoptotic follicles in group B was lower than that in group C on day 1 (13.75 ± 2.50% vs 27.0 ± 10.10%, p = 0.003), day 5 (11.75 ± 1.50% vs 51.0 ± 10.5%, p = 0.019) and day 7 (15.0 ± 5.10% vs 46.5 ± 21.75%, p = 0.018). These data have provided the first experimental evidence of the effect of HUMSC-CM on frozen-thawed OCTs in vitro. The results showed that the HUMSC-CM group provided a better protecting effect on the in-vitro culture of the cryopreserved OCTs compared to the SF-CM group.

Hypoxia-Related Marker GLUT-1, CAIX, Proliferative Index and Microvessel Density in Canine Oral Malignant Neoplasia

PubMed Central

Meier, Valeria; Guscetti, Franco; Roos, Malgorzata; Ohlerth, Stefanie; Pruschy, Martin; Rohrer Bley, Carla

2016-01-01

For various types of tumor therapy, it is suggested that co-targeting of tumor microenvironment, mainly tumor vasculature, mediates tumor response mechanisms. Immunohistochemistry for glucose transporter-1 (GLUT-1), carbonic anhydrase-IX (CAIX), Ki-67, and von Willebrand factor VIII for microvessel density (MVD) were performed on formalin-fixed paraffin-embedded samples of canine oral malignant neoplasms. Polarographic oxygen measurements (median pO2) and perfusion data via contrast-enhanced power Doppler ultrasound (median vascularity, median blood volume) provided additional information. Ninety-two samples were analyzed: sarcomas (n = 32), carcinomas (n = 30), and malignant melanomas (n = 30). Polarographic oxygen and perfusion data was available in 22.8% (sarcomas n = 9, carcinomas n = 7, melanomas n = 5), and 27.1% (sarcomas n = 10, carcinomas n = 8, melanomas n = 7) of cases, respectively. GLUT-1 expression was detected in 46.7% of all samples, and was generally weak. CAIX expression was found in 34.8% of all samples. Median Ki-67 score and MVD count was 19% and 17, respectively. The evaluation of the GLUT-1 score and continuous data showed significantly lower GLUT-1 levels in sarcomas (mean 5.1%, SD 6.2) versus carcinomas and melanomas (mean 16.5%/ 19.0%, SD 17.3/ 20.9, p = 0.001). The expression of CAIX correlated mildly positively with GLUT-1 (p = 0.018, rho = 0.250) as well as with Ki-67 (p = 0.014, rho = 0.295). MVD showed a significantly lower level in melanomas (mean 12.6, SD 7.7) versus sarcomas and carcinomas (mean 21.8/ 26.9, SD 13.0/20.4, p = 0.001). Median vascularity and blood volume were significantly lower in sarcomas (mean 10.4%, SD 11.0, and mean 6.3%, SD 6.5, respectively) versus carcinomas (mean 39.2%, SD 16.4 and mean 33.0%, SD 25.6, respectively) and melanomas (mean 36.0%, SD 18.3, and 31.5%, SD 24.5). Between the 3 histological groups, there was neither a significant difference in the GLUT-1 and CAIX score and continuous data, nor the Ki67 score, or polarographic oxygen measurements. GLUT-1 continuous data and Ki-67 (p<0.001, rho = 0.403), as well as Ki-67 and MVD (p = 0.029, rho = 0.228) correlated positively and a mild correlation was found between vascularity and GLUT-1 (p = 0.043, rho = 0.408). GLUT-1, CAIX, proliferative index and MVD levels were established as microenvironmental descriptors with the purpose of creating a baseline in order to follow changes seen in the tumor microenvironment after hypofractionated radiation with high doses. PMID:26906567

Assessing tumor vascularization as a potential biomarker of imatinib resistance in gastrointestinal stromal tumors by dynamic contrast-enhanced magnetic resonance imaging.

PubMed

Consolino, Lorena; Longo, Dario Livio; Sciortino, Marianna; Dastrù, Walter; Cabodi, Sara; Giovenzana, Giovanni Battista; Aime, Silvio

2017-07-01

Most metastatic gastrointestinal stromal tumors (GISTs) develop resistance to the first-line imatinib treatment. Recently, increased vessel density and angiogenic markers were reported in GISTs with a poor prognosis, suggesting that angiogenesis is implicated in GIST tumor progression and resistance. The purpose of this study was to investigate the relationship between tumor vasculature and imatinib resistance in different GIST mouse models using a noninvasive magnetic resonance imaging (MRI) functional approach. Immunodeficient mice (n = 8 for each cell line) were grafted with imatinib-sensitive (GIST882 and GIST-T1) and imatinib-resistant (GIST430) human cell lines. Dynamic contrast-enhanced MRI (DCE-MRI) was performed on GIST xenografts to quantify tumor vessel permeability (K trans ) and vascular volume fraction (v p ). Microvessel density (MVD), permeability (mean dextran density, MDD), and angiogenic markers were evaluated by immunofluorescence and western blot assays. Dynamic contrast-enhanced magnetic resonance imaging showed significantly increased vessel density (P < 0.0001) and permeability (P = 0.0002) in imatinib-resistant tumors compared to imatinib-sensitive ones. Strong positive correlations were observed between MRI estimates, K trans and v p , and their related ex vivo values, MVD (r = 0.78 for K trans and r = 0.82 for v p ) and MDD (r = 0.77 for K trans and r = 0.94 for v p ). In addition, higher expression of vascular endothelial growth factor receptors (VEGFR2 and VEFGR3) was seen in GIST430. Dynamic contrast-enhanced magnetic resonance imaging highlighted marked differences in tumor vasculature and microenvironment properties between imatinib-resistant and imatinib-sensitive GISTs, as also confirmed by ex vivo assays. These results provide new insights into the role that DCE-MRI could play in GIST characterization and response to GIST treatment. Validation studies are needed to confirm these findings.

LPS-induced microvascular leukocytosis can be assessed by blue-field entoptic phenomenon.

PubMed

Kolodjaschna, Julia; Berisha, Fatmire; Lung, Solveig; Schaller, Georg; Polska, Elzbieta; Jilma, Bernd; Wolzt, Michael; Schmetterer, Leopold

2004-08-01

Administration of low doses of Escherichia coli endotoxin [a lipopolysaccharide (LPS)] to humans enables the study of inflammatory mechanisms. The purpose of the present study was to investigate whether the blue-field entoptic technique may be used to quantify the increase in circulating leukocytes in the ocular microvasculature after LPS infusion. In addition, combined laser Doppler velocimetry and retinal vessel size measurement were used to study red blood cell movement. Twelve healthy male volunteers received 20 IU/kg iv LPS as a bolus infusion. Outcome parameters were measured at baseline and 4 h after LPS administration. In the first protocol (n = 6 subjects), ocular hemodynamic effects were assessed with the blue-field entoptic technique, the retinal vessel analyzer, and laser Doppler velocimetry. In the second protocol (n = 6 subjects), white blood cell (WBC) counts from peripheral blood samples and blue-field entoptic technique measurements were performed. LPS caused peripheral blood leukocytosis and increased WBC density in ocular microvessels (by 49%; P = 0.036) but did not change WBC velocity. In addition, retinal venous diameter was increased (by 9%; P = 0.008), but red blood cell velocity remained unchanged. The LPS-induced changes in retinal WBC density and leukocyte counts were significantly correlated (r = 0.87). The present study indicates that the blue-field entoptic technique can be used to assess microvascular leukocyte recruitment in vivo. In addition, our data indicate retinal venous dilation in response to endotoxin.

[An electron microscopic analysis of the stimulating and toxic effects of mumie-containing preparations].

PubMed

Rudnev, M I; Maliuk, V I; Stechenko, L A; Maliuk, V I; Fisun, O I; Kuftyreva, T P; Andreenko, T V

1993-01-01

Ultrastructural changes of myocardium cells, neurons of sensorimotor cerebral cortex, endothelium of blood microvessels were registered by transmissive electron microscopy in mice receiving rock balm preparations per os. Both stimulating and toxic effects were observed dependently on used concentrations. This necessitates dosage to be strictly observed.

Loss of the Endothelial Glycocalyx Links Albuminuria and Vascular Dysfunction

PubMed Central

Ferguson, Joanne K.; Burford, James L.; Gevorgyan, Haykanush; Nakano, Daisuke; Harper, Steven J.; Bates, David O.; Peti-Peterdi, Janos

2012-01-01

Patients with albuminuria and CKD frequently have vascular dysfunction but the underlying mechanisms remain unclear. Because the endothelial surface layer, a meshwork of surface-bound and loosely adherent glycosaminoglycans and proteoglycans, modulates vascular function, its loss could contribute to both renal and systemic vascular dysfunction in proteinuric CKD. Using Munich-Wistar-Fromter (MWF) rats as a model of spontaneous albuminuric CKD, multiphoton fluorescence imaging and single-vessel physiology measurements revealed that old MWF rats exhibited widespread loss of the endothelial surface layer in parallel with defects in microvascular permeability to both water and albumin, in both continuous mesenteric microvessels and fenestrated glomerular microvessels. In contrast to young MWF rats, enzymatic disruption of the endothelial surface layer in old MWF rats resulted in neither additional loss of the layer nor additional changes in permeability. Intravenous injection of wheat germ agglutinin lectin and its adsorption onto the endothelial surface layer significantly improved glomerular albumin permeability. Taken together, these results suggest that widespread loss of the endothelial surface layer links albuminuric kidney disease with systemic vascular dysfunction, providing a potential therapeutic target for proteinuric kidney disease. PMID:22797190

Effects of deformability of RBCs on their dynamics and blood flow passing through a stenosed microvessel: an immersed boundary-lattice Boltzmann approach

NASA Astrophysics Data System (ADS)

Alizadeh, As'ad; Dadvand, Abdolrahman

2018-02-01

In this paper, the motion of high deformable (healthy) and low deformable (sick) red blood cells in a microvessel with and without stenosis is simulated using a combined lattice Boltzmann-immersed boundary method. The RBC is considered as neo-Hookean elastic membrane with bending resistance. The motion and deformation of the RBC under different values of the Reynolds number are evaluated. In addition, the variations of blood flow resistance and time-averaged pressure due to the motion and deformation of the RBC are assessed. It was found that a healthy RBC moves faster than a sick one. The apparent viscosity and blood flow resistance are greater for the case involving the sick RBC. Blood pressure at the presence of stenosis and low deformable RBC increases, which is thought of as the reason of many serious diseases including cardiovascular diseases. As the Re number increases, the RBC deforms further and moves easier and faster through the stenosis. The results of this study were compared to the available experimental and numerical results, and good agreements were observed.

The wall traction induced by flowing red blood cells in model microvessels and its potential mechanotransduction

NASA Astrophysics Data System (ADS)

Freund, Jonathan; Vermot, Julien

2013-11-01

There is evidence in early embryonic development, even well before advective oxygen transport is important, that the presence of red bloods cells per se trigger essential steps of normal vascular development. For example, showed that sequestration of blood cells early in the development of a mouse, such that the hematocrit is reduced, suppresses normal vascular network development. Vascular development also provides a model for remodeling and angiogenesis. We consider the transient stresses associated with blood cells flowing in model microvessels of comparable diameter to those at early stages of development (6 μm to 12 μm). A detailed simulation tool is used to show that passing blood cells present a significant fluctuating traction signature on the vessel wall, well above the mean stresses. This is particularly pronounced for slow flows (<= 50 μm/s) or small diameters (<= 7 μm), for which root-mean-square wall traction fluctuations can exceed their mean. These events potentially present mechanotranduction triggers that direct development or remodeling. Attenuation of such fluctuating tractions by a viscoelastic endothelial glycocalyx layer is also considered. NSF supported.

Fusible core molding for the fabrication of branched, perfusable, three-dimensional microvessels for vascular tissue engineering.

PubMed

Martin, Cristina; Sofla, Aarash; Zhang, Boyang; Nunes, Sara S; Radisic, Milica

2013-03-01

A novel method for fabrication of branched, tubular, perfusable microvessels for use in vascular tissue engineering is reported. A tubular, elastomeric, biodegradable scaffold is first fabricated via a new, double fusible injection molding technique that uses a ternary alloy with a low melting temperature, Field's metal, and paraffin as sacrificial components. A cylindrical core metal of 500 μm or lower dia-meter with the target branching scaffold geometry is first constructed, then the metal structure is coated with paraffin and, finally, the metal-paraffin construct is embedded in polydimethylsiloxane (PDMS). The paraffin layer is then removed by heating and replaced by a biodegradable elastomeric pre-polymer that is subsequently UV-cured inside the PDMS. Next, the metal core is melted away and the PDMS is removed to attain the branched tubular elastomeric biodegradable scaffold. Finally, it is also demonstrated that human umbilical vein endothelial cells (HUVEC) were able to spread on the surface of the scaffold and form a confluent monolayer, confirming the potential of this new technique for making engineered blood vessels.

Immunoexpression of GLUT-1 and angiogenic index in pleomorphic adenomas, adenoid cystic carcinomas, and mucoepidermoid carcinomas of the salivary glands.

PubMed

de Souza, Lélia Batista; de Oliveira, Lucileide Castro; Nonaka, Cassiano Francisco Weege; Lopes, Maria Luiza Diniz de Sousa; Pinto, Leão Pereira; Queiroz, Lélia Maria Guedes

2017-06-01

This study aimed to evaluate and compare the immunoexpression of glucose transporter-1 (GLUT-1) and angiogenic index between pleomorphic adenomas (PAs), adenoid cystic carcinomas (ACCs), and mucoepidermoid carcinomas (MECs) of the salivary glands, and establish associations with the respective subtype/histological grade. Twenty PAs, 20 ACCs, and 10 MECs were submitted to morphological and immunohistochemical analysis. GLUT-1 expression was semi-quantitatively evaluated and angiogenic index was assessed by microvessel counts using anti-CD34 antibody. Higher GLUT-1 immunoexpression was observed in the MECs compared to PAs and ACCs (p = 0.022). Mean number of microvessels was 66.5 in MECs, 40.4 in PAs, and 21.2 in ACCs (p < 0.001). GLUT-1 expression and angiogenic index showed no significant correlation in the tumors studied. Results suggest that differences in biological behavior of the studied tumors are related to GLUT-1. Benign and malignant salivary gland tumors differ in the angiogenic index; however, angiogenesis may be independent of the tumor cell's metabolic demand.

Mechanisms of alveolar fibrosis after acute lung injury.

PubMed

Marinelli, W A; Henke, C A; Harmon, K R; Hertz, M I; Bitterman, P B

1990-12-01

In patients who die after severe acute lung injury, a dramatic fibroproliferative response occurs within the alveolar air space, interstitium, and microvessels. Profound shunt physiology, dead space ventilation, and pulmonary hypertension are the physiologic consequences of this fibroproliferative response. The anatomic pattern of the response is unique within each alveolar compartment. For example, the air space is obliterated by granulation tissue, with replicating mesenchymal cells, their connective tissue products, and an expanding network of intra-alveolar capillaries. In contrast, the vascular fibroproliferative response is dominated by mesenchymal cell replication and connective tissue deposition within the walls of microvessels. Despite the unique anatomic features of these fibroproliferative processes, the regulatory signals involved are likely to be similar. Although our current understanding of the signals regulating the fibroproliferative response to acute lung injury is limited, inferences can be made from in vitro studies of mesenchymal cell behavior and several better understood fibroproliferative processes, including wound healing and chronic fibrotic lung diseases. As clinicians, our future ability to enhance effective lung repair will likely utilize therapeutic strategies specifically targeted to the signals that regulate the fibroproliferative process within the alveolar microenvironment.

Normobaric Hyperoxia Reduces Blood Occludin Fragments in Rats and Patients With Acute Ischemic Stroke.

PubMed

Shi, Shuhai; Qi, Zhifeng; Ma, Qingfeng; Pan, Rong; Timmins, Graham S; Zhao, Yongmei; Shi, Wenjuan; Zhang, Yunzhou; Ji, Xunming; Liu, Ke Jian

2017-10-01

Damage of the blood-brain barrier (BBB) increases the incidence of neurovascular complications, especially for cerebral hemorrhage after tPA (tissue-type plasminogen activator) therapy. Currently, there is no effective method to evaluate the extent of BBB damage to guide tPA use. Herein, we investigated whether blood levels of tight junction proteins could serve as biomarker of BBB damages in acute ischemic stroke (AIS) in both rats and patients. We examined whether this biomarker could reflect the extent of BBB permeability during cerebral ischemia/reperfusion and the effects of normobaric hyperoxia (NBO) on BBB damage. Rats were exposed to NBO (100% O 2 ) or normoxia (21% O 2 ) during middle cerebral artery occlusion. BBB permeability was determined. Occludin and claudin-5 in blood and cerebromicrovessels were measured. Patients with AIS were assigned to oxygen therapy or room air for 4 hours, and blood occludin and claudin-5 were measured at different time points after stroke. Cerebral ischemia/reperfusion resulted in the degradation of occludin and claudin-5 in microvessels, leading to increased BBB permeability in rats. In blood samples, occludin increased with 4-hour ischemia and remained elevated during reperfusion, correlating well with its loss from ischemic cerebral microvessels. NBO treatment both prevented occludin degradation in microvessels and reduced occludin levels in blood, leading to improved neurological functions in rats. In patients with AIS receiving intravenous tPA thrombolysis, the blood occludin was already elevated when patients arrived at hospital (within 4.5 hours since symptoms appeared) and remained at a high level for 72 hours. NBO significantly lowered the level of blood occludin and improved neurological functions in patients with AIS. Blood occludin may be a clinically viable biomarker for evaluating BBB damage during ischemia/reperfusion. NBO therapy has the potential to reduce blood occludin, protect BBB, and improve outcome in AIS patients with intravenous tPA thrombolysis. URL: http://www.clinicaltrials.gov. Unique identifier: NCT02974283. © 2017 American Heart Association, Inc.

Assessing blood flow, microvasculature, erythema and redness in hypertrophic scars: A cross sectional study showing different features that require precise definitions.

PubMed

Jaspers, M E H; Stekelenburg, C M; Simons, J M; Brouwer, K M; Vlig, M; van den Kerckhove, E; Middelkoop, E; van Zuijlen, P P M

2017-08-01

In hypertrophic scar assessment, laser Doppler imaging (LDI), colorimetry and subjective assessment (POSAS) can be used to evaluate blood flow, erythema and redness, respectively. In addition, the microvasculature (i.e. presence of microvessels) can be determined by immunohistochemistry. These measurement techniques are frequently used in clinical practice and/or in research to evaluate treatment response and monitor scar development. However, until now it has not been tested to what extent the outcomes of these techniques are associated, whilst the outcome terms are frequently used interchangeably or replaced by the umbrella term 'vascularization'. This is confusing, as every technique seems to measure a specific feature. Therefore, we evaluated the correlations of the four measurement techniques. We included 32 consecutive patients, aged ≥18 years, who underwent elective resection of a hypertrophic scar. Pre-operatively, we performed LDI (measuring blood flow), colorimetry (measuring erythema) and the POSAS (subjective redness) within the predefined scar area of interest (∼1.5cm). Subsequently, the scar was excised and the area of interest was sent for immunohistochemistry, to determine the presence of microvessels. Only a statistically significant correlation was found between erythema values (colorimetry) and subjective redness assessment (POSAS) (r=0.403, p=0.030). We found no correlations between the outcomes of LDI, immunohistochemistry and colorimetry. Blood flow, the presence of microvessels and erythema appear to be different hypertrophic scar features because they show an absence of correlation. Therefore, in the field of scar assessment, these outcome terms cannot be used interchangeably. In addition, we conclude that the term 'vascularization' does not seem appropriate to serve as an umbrella term. The use of precise definitions in research as well as in clinical practice is recommended. Copyright © 2017 Elsevier Ltd and ISBI. All rights reserved.

Angiogenesis Research to Improve Therapies for Vascular Leak Syndromes, Intra-Abdominal Adhesions, and Arterial Injuries

DTIC Science & Technology

2007-02-01

characterization of functional human microvessels in immunodeficient mice. Lab Invest. 2001;81:453-463. 14. Rafii S, Lyden D. Therapeutic stem and progenitor cell... Rafii S, Wu MH, et al. Evidence for circulating bone marrow-derived endothelial cells. Blood. 1998;92:362-367. 32. Hristov M, Erl W, Weber PC

Shock Initiation and Equation of State of Ammonium Nitrate

NASA Astrophysics Data System (ADS)

Robbins, David; Sheffield, Steve; Dattelbaum, Dana; Chellappa, Raja; Velisavljevic, Nenad

2013-06-01

Ammonium nitrate (AN) is a widely used fertilizer and mining explosive commonly found in ammonium nitrate-fuel oil. Neat AN is a non-ideal explosive with measured detonation velocities approaching 4 km/s. Previously, we reported a thermodynamically-complete equation of state for AN based on its maximum density, and showed that near-full density AN did not initiate when subjected to shock input conditions up to 22 GPa. In this work, we extend these initial results, by presenting new Hugoniot data for intermediate density neat AN obtained from gas gun-driven plate impact experiments. AN at densities from 1.8 to 1.5 g/cm3 were impacted into LiF windows using a two-stage light gas gun. Dual VISARs were used to measure the interfacial particle velocity wave profile as a function of time following impact. The new Hugoniot data, in addition to updates to thermodynamic parameters derived from structural analysis and vibrational spectroscopy measurements in high pressure diamond anvil cell experiments, are used to refine the unreacted EOS for AN. Furthermore, shock initiation of neat AN was observed as the initial porosity increased (density decreased). Insights into the relationship(s) between initial density and shock initiation sensitivity are also presented, from evidence of shock initiation in the particle velocity profiles obtained for the lower density AN samples.

A noninvasive multimodal technique to monitor brain tumor vascularization

NASA Astrophysics Data System (ADS)

Saxena, Vishal; Gonzalez-Gomez, Ignacio; Laug, Walter E.

2007-09-01

Determination of tumor oxygenation at the microvascular level will provide important insight into tumor growth, angiogenesis, necrosis and therapeutic response and will facilitate to develop protocols for studying tumor behavior. The non-ionizing near infrared spectroscopy (NIRS) technique has the potential to differentiate lesion and hemoglobin dynamics; however, it has a limited spatial resolution. On the other hand, magnetic resonance imaging (MRI) has achieved high spatial resolution with excellent tissue discrimination but is more susceptible to limited ability to monitor the hemoglobin dynamics. In the present work, the vascular status and the pathophysiological changes that occur during tumor vascularization are studied in an orthotopic brain tumor model. A noninvasive multimodal approach based on the NIRS technique, namely steady state diffuse optical spectroscopy (SSDOS) along with MRI, is applied for monitoring the concentrations of oxyhemoglobin, deoxyhemoglobin and water within tumor region. The concentrations of oxyhemoglobin, deoxyhemoglobin and water within tumor vasculature are extracted at 15 discrete wavelengths in a spectral window of 675-780 nm. We found a direct correlation between tumor size, intratumoral microvessel density and tumor oxygenation. The relative decrease in tumor oxygenation with growth indicates that though blood vessels infiltrate and proliferate the tumor region, a hypoxic trend is clearly present.

[Suppression of COX-2 protein to cell apoptosis in non-small cell lung cancer].

PubMed

Sun, Limei; Zhao, Yue; Wang, Lujian; Song, Min; Song, Jiye

2007-06-20

One of mechanisms of carcinogenesis is suppression of cell apoptosis which leads to accumulation of aberrant cells. The aim of this study is to investigate cell apoptosis and COX-2 protein expression in non-small cell lung cancer (NSCLC). Cell apoptosis, expression of COX-2 and microvessel density (MVD) were detcted in 111 NSCLC samples by TdT-mediated dUTP nick end labeling (TUNEL) technique and immunohistochemical staining. The positive rate of COX-2 protein expression was 67.6% (75/111), and there were 53 patients with high level cell apoptosis (47.7%). Expression of COX-2 protien was significantly related to TNM stages (P=0.025) and lymph node metastasis (P=0.018). The MVD in NSCLC tissues with positive COX-2 expression was significantly higher than that in negative expression ones (P=0.000). COX model showed that lymph node metastasis (P=0.006) and positive expression of COX-2 protein (P=0.000) were independent prognostic factors of NSCLC. The expression of COX-2 protein may suppress cell apoptosis of tumor, and it may serve as a potential marker of prognosis for NSCLC.

Prognostic significance of thymidylate synthase (TS) expression in cutaneous malignant melanoma.

PubMed

Shimizu, A; Kaira, K; Yasuda, M; Asao, T; Ishikawa, O

2016-01-01

Thymidylate synthase (TS) plays an essential role in the pathogenesis and development of cancer, and TS-targeting agents have been widely used against different types of cancers. However, it remains still unclear whether or not TS is expressed in malignant melanoma. We conducted the clinicopathological study to investigate the prognostic significance of TS expression in cutaneous malignant melanoma. Ninety-nine patients with surgically resected cutaneous malignant melanoma were assessed. Tumor sections were stained by immunohistochemistry for TS, Ki-67, and microvessel density (MVD) determined by CD34. TS was positively expressed in 26% (26 out of 99). The expression of TS was significantly associated with T factor, cell proliferation (Ki-67) and MVD (CD34). By Spearman's rank test, TS expression was significantly correlated with Ki67 and CD34. By univariate analysis, ulceration, disease stage, TS, Ki-67 and CD34 had a significant relationship with survival. Multivariate analysis confirmed that TS was an independent prognostic factor for poor prognosis of cutaneous malignant melanoma. The positive expression of TS could be a useful marker for predicting poor prognosis in patients with cutaneous malignant melanoma, and TS-targeting agents may be worth trying for the treatment of this dismal disease.

Quantification of video-taped images in microcirculation research using inexpensive imaging software (Adobe Photoshop).

PubMed

Brunner, J; Krummenauer, F; Lehr, H A

2000-04-01

Study end-points in microcirculation research are usually video-taped images rather than numeric computer print-outs. Analysis of these video-taped images for the quantification of microcirculatory parameters usually requires computer-based image analysis systems. Most software programs for image analysis are custom-made, expensive, and limited in their applicability to selected parameters and study end-points. We demonstrate herein that an inexpensive, commercially available computer software (Adobe Photoshop), run on a Macintosh G3 computer with inbuilt graphic capture board provides versatile, easy to use tools for the quantification of digitized video images. Using images obtained by intravital fluorescence microscopy from the pre- and postischemic muscle microcirculation in the skinfold chamber model in hamsters, Photoshop allows simple and rapid quantification (i) of microvessel diameters, (ii) of the functional capillary density and (iii) of postischemic leakage of FITC-labeled high molecular weight dextran from postcapillary venules. We present evidence of the technical accuracy of the software tools and of a high degree of interobserver reliability. Inexpensive commercially available imaging programs (i.e., Adobe Photoshop) provide versatile tools for image analysis with a wide range of potential applications in microcirculation research.

Prognostic Impact of PHIP Copy Number in Melanoma: Linkage to Ulceration

PubMed Central

Nosrati, Mehdi; Tong, Schuyler; Wu, Clayton; Thummala, Suresh; Dar, Altaf A.; Leong, Stanley P.L.; Cleaver, James E.; Sagebiel, Richard W.; Miller, James R.; Kashani-Sabet, Mohammed

2013-01-01

Ulceration is an important prognostic factor in melanoma whose biologic basis is poorly understood. Here we assessed the prognostic impact of pleckstrin homology domain-interacting protein (PHIP) copy number and its relationship to ulceration. PHIP copy number was determined using fluorescence in situ hybridization (FISH) in a tissue microarray cohort of 238 melanomas. Elevated PHIP copy number was associated with significantly reduced DMFS (P = 0.01) and DSS (P = 0.009) by Kaplan-Meier analyses. PHIP FISH scores were independently predictive of DMFS (P = 0.03) and DSS (P = 0.03). Increased PHIP copy number was an independent predictor of ulceration status (P = 0.04). The combined impact of increased PHIP copy number and tumor vascularity on ulceration status was highly significant (P< 0.0001). Stable suppression of PHIP in human melanoma cells resulted in significantly reduced glycolytic activity in vitro, with lower expression of LDH5, HIF1A, and VEGF, and was accompanied by reduced microvessel density in vivo. These results provide further support for PHIP as a molecular prognostic marker of melanoma, and reveal a significant linkage between PHIP levels and ulceration. Moreover, they suggest that ulceration may be driven by increased glycolysis and angiogenesis. PMID:24005052

Pigment Epithelium Derived Factor Inhibits the Growth of Human Endometrial Implants in Nude Mice and of Ovarian Endometriotic Stromal Cells In Vitro

PubMed Central

Sun, Yanmei; Che, Xuan; Zhu, Libo; Zhao, Mengdan; Fu, Guofang; Huang, Xiufeng; Xu, Hong; Hu, Fuqiang; Zhang, Xinmei

2012-01-01

Angiogenesis is a prerequisite for the formation and development of endometriosis. Pigment epithelium derived factor (PEDF) is a natural inhibitor of angiogenesis. We previously demonstrated a reduction of PEDF in the peritoneal fluid, serum and endometriotic lesions from women with endometriosis compared with women without endometriosis. Here, we aim to investigate the inhibitory effect of PEDF on human endometriotic cells in vivo and in vitro. We found that PEDF markedly inhibited the growth of human endometrial implants in nude mice and of ovarian endometriotic stromal cells in vitro by up-regulating PEDF expression and down-regulating vascular endothelial growth factor (VEGF) expression. Moreover, apoptotic index was significantly increased in endometriotic lesions in vivo and endometriotic stromal cells in vitro when treated with PEDF. In mice treated with PEDF, decreased microvessel density labeled by Von Willebrand factor but not by α-Smooth Muscle Actin was observed in endometriotic lesions. And it showed no increase in PEDF expression of the ovary and uterus tissues. These findings suggest that PEDF gene therapy may be a new treatment for endometriosis. PMID:23028859

In vivo photoacoustic imaging of uterine cervical lesion and its image processing based on light propagation in biological medium

NASA Astrophysics Data System (ADS)

Okawa, Shinpei; Sei, Kiguna; Hirasawa, Takeshi; Irisawa, Kaku; Hirota, Kazuhiro; Wada, Takatsugu; Kushibiki, Toshihiro; Furuya, Kenichi; Ishihara, Miya

2017-03-01

For diagnosis of cervical cancer, screening by colposcope and successive biopsy are usually carried out. Colposcope, which is a mesoscope, is used to examine surface of the cervix and to find precancerous lesion grossly. However, the accuracy of colposcopy depends on the skills of the examiner and is inconsistent as a result. Additionally, colposcope lacks depth information. It is known that microvessel density and blood flow in cervical lesion increases associated with angiogenesis. Therefore, photoacoustic imaging (PAI) to detect angiogenesis in cervical lesion has been studied. PAI can diagnose cervical lesion sensitively and provide depth information. The authors have been investigating the efficacy of PAI in the diagnoses of the cervical lesion and cancer by use of the PAI and ultrasonography system with transvaginal probe developed by Fujifilm Corporation. For quantitative diagnosis by use of PAI, it is required to take the light propagation in biological medium into account. The image reconstruction of the absorption coefficient from the PA image of cervix by use of the simulation of light propagation based on finite element method has been tried in this study. Numerical simulation, phantom experiment and in vivo imaging were carried out.

Quantitative real-time reverse transcription polymerase chain reaction: normalization to rRNA or single housekeeping genes is inappropriate for human tissue biopsies.

PubMed

Tricarico, Carmela; Pinzani, Pamela; Bianchi, Simonetta; Paglierani, Milena; Distante, Vito; Pazzagli, Mario; Bustin, Stephen A; Orlando, Claudio

2002-10-15

Careful normalization is essential when using quantitative reverse transcription polymerase chain reaction assays to compare mRNA levels between biopsies from different individuals or cells undergoing different treatment. Generally this involves the use of internal controls, such as mRNA specified by a housekeeping gene, ribosomal RNA (rRNA), or accurately quantitated total RNA. The aim of this study was to compare these methods and determine which one can provide the most accurate and biologically relevant quantitative results. Our results show significant variation in the expression levels of 10 commonly used housekeeping genes and 18S rRNA, both between individuals and between biopsies taken from the same patient. Furthermore, in 23 breast cancers samples mRNA and protein levels of a regulated gene, vascular endothelial growth factor (VEGF), correlated only when normalized to total RNA, as did microvessel density. Finally, mRNA levels of VEGF and the most popular housekeeping gene, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), were significantly correlated in the colon. Our results suggest that the use of internal standards comprising single housekeeping genes or rRNA is inappropriate for studies involving tissue biopsies.

Ginsenoside Rg1 and platelet-rich fibrin enhance human breast adipose-derived stem cells function for soft tissue regeneration

PubMed Central

Li, Hong-Mian; Peng, Qi-Liu; Huang, Min-Hong; Li, De-Quan; Liang, Yi-Dan; Chi, Gang-Yi; Li, De-Hui; Yu, Bing-Chao; Huang, Ji-Rong

2016-01-01

Adipose-derived stem cells (ASCs) can be used to repair soft tissue defects, wounds, burns, and scars and to regenerate various damaged tissues. The cell differentiation capacity of ASCs is crucial for engineered adipose tissue regeneration in reconstructive and plastic surgery. We previously reported that ginsenoside Rg1 (G-Rg1 or Rg1) promotes proliferation and differentiation of ASCs in vitro and in vivio. Here we show that both G-Rg1 and platelet-rich fibrin (PRF) improve the proliferation, differentiation, and soft tissue regeneration capacity of human breast adipose-derived stem cells (HBASCs) on collagen type I sponge scaffolds in vitro and in vivo. Three months after transplantation, tissue wet weight, adipocyte number, intracellular lipid, microvessel density, and gene and protein expression of VEGF, HIF-1α, and PPARγ were higher in both G-Rg1- and PRF-treated HBASCs than in control grafts. More extensive new adipose tissue formation was evident after treatment with G-Rg1 or PRF. In summary, G-Rg1 and/or PRF co-administration improves the function of HBASCs for soft tissue regeneration engineering. PMID:27191987

OPC-28326, a selective femoral arterial vasodilator, augments ischemia induced angiogenesis.

PubMed

Sumi, Makoto; Sata, Masataka; Hashimoto, Ayako; Imaizumi, Takashi; Yanaga, Katsuhiko; Ohki, Takao; Mori, Toyoki; Nagai, Ryozo

2007-05-01

OPC-28326, 4-(N-methyl-2-phenylethylamino)-1-(3,5-dimethyl-4-propionyl-aminobenzoyl) piperidine hydrochloride monohydrate, is a newly developed selective peripheral vasodilator and increases blood flow to lower extremities with alpha2-adrenergic antagonist property. Here, we investigated the effect of OPC-28326 on ischemia-induced angiogenesis. OPC-28326 enhanced tube formation by human aortic endothelial cells (HAECs). Moreover, OPC-28326 enhanced the number of microvessels sprouting from aortic rings embedded in collagen gel. OPC-28326 markedly induced phosphorylation of endothelial nitric oxide synthase (eNOS) in HAECs via phosphatidylinositol-3 kinase PI3K/Akt (PI3K/Akt) pathway. Next, the angiogenic effect of OPC-28326 was evaluated in a mouse hindlimb ischemia model. Blood flow recovery to the ischemic leg was significantly enhanced by OPC-28326. Furthermore, anti-CD31 immunostaining revealed that OPC-28326 increased capillary density in the ischemic muscle. However, OPC-28326 failed to promote blood flow recovery in ischemic hindlimb in eNOS-deficient mice. These results suggest that OPC-28326 promotes angiogenesis, which was associated with activation of eNOS via PI3K/Akt pathway. OPC-28326 might be promising to treat patients with ischemic vascular diseases.

Tobacco Retail Outlet Density and Young Adult Tobacco Initiation

PubMed Central

Pearson, Jennifer L.; Anesetti-Rothermel, Andrew; Xiao, Haijun; Kirchner, Thomas R.; Vallone, Donna

2016-01-01

Background: A growing body of evidence indicates that the density of tobacco retail outlets around the home residence may influence tobacco use among youth and adults. The purpose of this study was to examine the impact of neighborhood tobacco retail outlet density on young adult initiation of different tobacco product types. Methods: Cross-sectional data from a 2013 nationally representative sample of young adults aged 18–34 was examined in relation to a 2012 geocoded listing of all outlets likely to sell tobacco in the United States. Separate multivariable logistic regression analyses examined associations between neighborhood outlet density and past 6 months first use of cigarettes, non-cigarette combustible products, and noncombustible products among adults aged 18–24 and 25–34. Results: Outlet density was significantly associated with recent initiation of cigarettes and other combustibles, but this impact varied for younger and older groups. Increased density was significantly associated with a higher likelihood of initiating cigarette use among adults aged 25–34 (OR = 3.75, 95% CI = 1.18, 11.90), and of initiating non-cigarette combustible use among 18–24 year olds (OR = 3.16, 95% CI = 1.03, 9.74). There was no impact of outlet density on recent noncombustible product initiation among either group. Conclusion: This study is the first to examine the impact of tobacco outlet density on young adult initiation of cigarettes and other tobacco products. Findings demonstrate that residential neighborhood outlet density is associated with recent initiation of combustible products and this effect varies by product type and age. The tobacco outlet environment may be a critical factor in promoting young adult tobacco use initiation. PMID:25666816

Surgery accelerates the development of endometriosis in mice.

PubMed

Long, Qiqi; Liu, Xishi; Guo, Sun-Wei

2016-09-01

Surgery is currently the mainstay treatment for solid tumors and many benign diseases, including endometriosis, and women tend to receive substantially more surgeries than men mainly because of gynecological and cosmetic surgeries. Despite its cosmetic, therapeutic, or even life-saving benefits, surgery is reported to increase the cancer risk and promotes cancer metastasis. Surgery activates adrenergic signaling, which in turn suppresses cell-mediated immunity and promotes angiogenesis and metastasis. Because immunity, angiogenesis, and invasiveness are all involved in the pathophysiology of endometriosis, it is unclear whether surgery may accelerate the development of endometriosis. The objective of the study was to test the hypothesis that surgery activates adrenergic signaling, increases angiogenesis, and accelerates the growth of endometriotic lesions. This was a prospective, randomized experimentation. The first experiment used 42 female adult Balb/C mice, and the second used 90 female adult Balb/C mice. In experiment 1, 3 days after the induction of endometriosis, mice were randomly divided into 3 groups of approximately equal sizes, control, laparotomy, and mastectomy. In experiment 2, propranolol infusion via Alzet pumps was used to forestall the effect of sympathetic nervous system activation by surgery. In both experiments, mice were evaluated 2 weeks after surgery. Lesion size, hotplate latency, and immunohistochemistry analysis of vascular endothelial growth factor, CD31-positive microvessels, proliferating cell nuclear antigen, phosphorylated cyclic adenosine monophosphate-responsive element-binding protein, β2-adrenergic receptor (ADRB)-2, ADRB1, ADRB3, ADRA1, and ADRA2 in ectopic implants. Both mastectomy and laparotomy increased lesion weight and exacerbated hyperalgesia, increased microvessel density and elevated the immunoreactivity against ADRB2, phosphorylated cyclic adenosine monophosphate-responsive element-binding protein, vascular endothelial growth factor, and proliferating cell nuclear antigen but not ADRB1, ADRB3, ADRA1, and ADRA2, suggesting activated adrenergic signaling, increased angiogenesis, and accelerated growth of endometriotic lesions. β-Blockade completely abrogated the facilitory effect of surgery, further underscoring the critical role of β-adrenergic signaling in mediating the effect of surgery. Surgery activates adrenergic signaling, increases angiogenesis, and accelerates the growth of endometriotic lesions in the mouse, but such a facilitory effect of surgery can be completely abrogated by β-blockade. Whether surgery can promote the development of endometriosis in humans warrants further investigation. Copyright © 2016 Elsevier Inc. All rights reserved.

Biodegradable polymeric micelles encapsulated JK184 suppress tumor growth through inhibiting Hedgehog signaling pathway

NASA Astrophysics Data System (ADS)

Zhang, Nannan; Liu, Shichang; Wang, Ning; Deng, Senyi; Song, Linjiang; Wu, Qinjie; Liu, Lei; Su, Weijun; Wei, Yuquan; Xie, Yongmei; Gong, Changyang

2015-01-01

JK184 can specially inhibit Gli in the Hedgehog (Hh) pathway, which showed great promise for cancer therapeutics. For developing aqueous formulation and improving anti-tumor activity of JK184, we prepared JK184 encapsulated MPEG-PCL micelles by the solid dispersion method without using surfactants or toxic organic solvents. The cytotoxicity and cellular uptake of JK184 micelles were both increased compared with the free drug. JK184 micelles induced more apoptosis and blocked proliferation of Panc-1 and BxPC-3 tumor cells. In addition, JK184 micelles exerted a sustained in vitro release behavior and had a stronger inhibitory effect on proliferation, migration and invasion of HUVECs than free JK184. Furthermore, JK184 micelles had stronger tumor growth inhibiting effects in subcutaneous Panc-1 and BxPC-3 tumor models. Histological analysis showed that JK184 micelles improved anti-tumor activity by inducing more apoptosis, decreasing microvessel density and reducing expression of CD31, Ki67, and VEGF in tumor tissues. JK184 micelles showed a stronger inhibition of Gli expression in Hh signaling, which played an important role in pancreatic carcinoma. Furthermore, circulation time of JK184 in blood was prolonged after entrapment in polymeric micelles. Our results suggested that JK184 micelles are a promising drug candidate for treating pancreatic tumors with a highly inhibitory effect on Hh activity.JK184 can specially inhibit Gli in the Hedgehog (Hh) pathway, which showed great promise for cancer therapeutics. For developing aqueous formulation and improving anti-tumor activity of JK184, we prepared JK184 encapsulated MPEG-PCL micelles by the solid dispersion method without using surfactants or toxic organic solvents. The cytotoxicity and cellular uptake of JK184 micelles were both increased compared with the free drug. JK184 micelles induced more apoptosis and blocked proliferation of Panc-1 and BxPC-3 tumor cells. In addition, JK184 micelles exerted a sustained in vitro release behavior and had a stronger inhibitory effect on proliferation, migration and invasion of HUVECs than free JK184. Furthermore, JK184 micelles had stronger tumor growth inhibiting effects in subcutaneous Panc-1 and BxPC-3 tumor models. Histological analysis showed that JK184 micelles improved anti-tumor activity by inducing more apoptosis, decreasing microvessel density and reducing expression of CD31, Ki67, and VEGF in tumor tissues. JK184 micelles showed a stronger inhibition of Gli expression in Hh signaling, which played an important role in pancreatic carcinoma. Furthermore, circulation time of JK184 in blood was prolonged after entrapment in polymeric micelles. Our results suggested that JK184 micelles are a promising drug candidate for treating pancreatic tumors with a highly inhibitory effect on Hh activity. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr06300g

Effects of Erythropoietin on Adipose Tissue: A Possible Strategy in Refilling

PubMed Central

Sabbatini, Maurizio; Bosetti, Michela; Borrone, Alessia; Boldorini, Renzo; Taveggia, Antonio; Verna, Giovanni; Cannas, Mario

2015-01-01

Background: The increased resorption and the difficulty of the fat graft take following autologous fat transplantation procedure are associated with reduced fat tissue revascularization and increased apoptosis of adipose cells. We suppose that the lipofilling procedure induces an inflammatory environment within the fat graft mass, whose evolution influences the efficacy of autologous fat graft survival. Erythropoietin (EPO) is a glycoprotein hormone known to exert angiogenetic and anti-inflammatory effects; therefore, our purpose was to investigate its reaction with adipose tissue used in lipofilling. Methods: Fat masses were harvested using manual suction lipectomy and then seeded on dishes in appropriate culture and treated for 3 weeks with 3 doses of EPO. CD31 and CD68 immunohistochemistry was used to identify microvessels and several infiltrating leukocyte cells. Results: Following EPO administration, we have detected an increase in the number of CD31-positive microvessel endothelium cells and CD31-positive small leukocytes and a reduction of CD68-positive cells. These effects were more conspicuous following higher EPO dose. Conclusions: Our findings evidence EPO treatment as a useful strategy to sustain the revascularization of grafted tissue and to reduce its inflammatory state. PMID:26034645

SSeCKS/AKAP12 induces repulsion between human prostate cancer and microvessel endothelial cells through the activation of Semaphorin 3F.

PubMed

Xie, Wen; Su, Wei; Zhang, Lijuan; Shang, Qingkun; Su, Bing

2017-09-02

Metastasis remains the primary cause of prostate cancer related death. Cancer cells need to contact endothelial cells and disrupt endothelial junctions to cross the endothelium for invasion and metastasis. The suppression of heterotypic repulsion between cancer and endothelial cells allows cancer cells to invade into the surrounding tissue. Here, we demonstrate that SSeCKS/AKAP12 induced repulsion between human prostate cancer and microvessel endothelial cells, which was mediated by an angiogenesis inhibitor Semaphorin 3F. Moreover, we examined AKAP12 and Semaphorin 3F mRNA expression in 42 prostate cancer and 30 benign prostatic hyperplasia tissue samples, and found that the expression of AKAP12 and Semaphorin 3F mRNA was inversely associated with the degree of aggressiveness of prostate cancer cells and tissues. An ordinal logistic regression analysis indicates that there is a positive association between the expression of AKAP12 and Semaphorin 3F in prostate cancer, suggesting that the activation of Semaphorin 3F by SSeCKS/AKAP12 may be involved in prostate cancer progression and metastasis. Copyright © 2017 Elsevier Inc. All rights reserved.

Analysis of focal spared areas in fatty liver using color Doppler imaging and contrast-enhanced microvessel display sonography.

PubMed

Liu, Li-Ping; Dong, Bao-Wei; Yu, Xiao-Ling; Zhang, Da-Kun; Li, Xin; Li, Hua

2008-03-01

The purpose of this study was to investigate whether focal fatty sparing (FFS) formation in the liver relates to aberrant blood flow. Sixty-three FFSs of the liver in 52 patients were examined by color Doppler flow imaging and contrast-enhanced microvessel display sonography. The 63 FFSs included 16 FFSs in the porta hepatis, 14 FFSs around the gallbladder fossa, and 33 other FFSs. The control group included patients with a diagnosis of fatty liver but no FFSs or focal lesions near the porta hepatis. Fourteen of 16 FFSs in the porta hepatis showed venous blood toward those areas that were differentiated from the portal and hepatic veins. Focal fatty sparings in the hilus hepatis correlated with aberrant veins, having a statistical significance compared with the control group (P < .0001). Seven of 14 FFSs around the gallbladder fossa contained blood vessels, 5 of them veins and the remaining 2 arteries. Two FFSs were located around hemangiomas. Three FFSs were located around maldeveloped vessels. The blood supply to an FFS in the porta hepatis may be correlated with aberrant veins. Focal fatty sparings around the gallbladder fossa may be associated with aberrant blood flow.

Flow of Red Blood Cells in Stenosed Microvessels.

PubMed

Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

2016-06-20

A computational study is presented on the flow of deformable red blood cells in stenosed microvessels. It is observed that the Fahraeus-Lindqvist effect is significantly enhanced due to the presence of a stenosis. The apparent viscosity of blood is observed to increase by several folds when compared to non-stenosed vessels. An asymmetric distribution of the red blood cells, caused by geometric focusing in stenosed vessels, is observed to play a major role in the enhancement. The asymmetry in cell distribution also results in an asymmetry in average velocity and wall shear stress along the length of the stenosis. The discrete motion of the cells causes large time-dependent fluctuations in flow properties. The root-mean-square of flow rate fluctuations could be an order of magnitude higher than that in non-stenosed vessels. Several folds increase in Eulerian velocity fluctuation is also observed in the vicinity of the stenosis. Surprisingly, a transient flow reversal is observed upstream a stenosis but not downstream. The asymmetry and fluctuations in flow quantities and the flow reversal would not occur in absence of the cells. It is concluded that the flow physics and its physiological consequences are significantly different in micro- versus macrovascular stenosis.

Flow of Red Blood Cells in Stenosed Microvessels

NASA Astrophysics Data System (ADS)

Vahidkhah, Koohyar; Balogh, Peter; Bagchi, Prosenjit

2016-06-01

A computational study is presented on the flow of deformable red blood cells in stenosed microvessels. It is observed that the Fahraeus-Lindqvist effect is significantly enhanced due to the presence of a stenosis. The apparent viscosity of blood is observed to increase by several folds when compared to non-stenosed vessels. An asymmetric distribution of the red blood cells, caused by geometric focusing in stenosed vessels, is observed to play a major role in the enhancement. The asymmetry in cell distribution also results in an asymmetry in average velocity and wall shear stress along the length of the stenosis. The discrete motion of the cells causes large time-dependent fluctuations in flow properties. The root-mean-square of flow rate fluctuations could be an order of magnitude higher than that in non-stenosed vessels. Several folds increase in Eulerian velocity fluctuation is also observed in the vicinity of the stenosis. Surprisingly, a transient flow reversal is observed upstream a stenosis but not downstream. The asymmetry and fluctuations in flow quantities and the flow reversal would not occur in absence of the cells. It is concluded that the flow physics and its physiological consequences are significantly different in micro- versus macrovascular stenosis.

DEspR roles in tumor vasculo-angiogenesis, invasiveness, CSC-survival and anoikis resistance: a 'common receptor coordinator' paradigm.

PubMed

Herrera, Victoria L; Decano, Julius L; Tan, Glaiza A; Moran, Ann M; Pasion, Khristine A; Matsubara, Yuichi; Ruiz-Opazo, Nelson

2014-01-01

A priori, a common receptor induced in tumor microvessels, cancer cells and cancer stem-like cells (CSCs) that is involved in tumor angiogenesis, invasiveness, and CSC anoikis resistance and survival, could underlie contemporaneous coordination of these events rather than assume stochasticity. Here we show that functional analysis of the dual endothelin1/VEGFsignal peptide receptor, DEspR, (formerly named Dear, Chr.4q31.2) supports the putative common receptor paradigm in pancreatic ductal adenocarcinoma (PDAC) and glioblastoma (GBM) selected for their invasiveness, CD133+CSCs, and polar angiogenic features. Unlike normal tissue, DEspR is detected in PDAC and GBM microvessels, tumor cells, and CSCs isolated from PDAC-Panc1 and GBM-U87 cells. DEspR-inhibition decreased angiogenesis, invasiveness, CSC-survival and anoikis resistance in vitro, and decreased Panc1-CSC and U87-CSC xenograft tumor growth, vasculo-angiogenesis and invasiveness in nude(nu/nu) rats, suggesting that DEspR activation would coordinate these tumor progression events. As an accessible, cell-surface 'common receptor coordinator', DEspR-inhibition defines a novel targeted-therapy paradigm for pancreatic cancer and glioblastoma.

DEspR Roles in Tumor Vasculo-Angiogenesis, Invasiveness, CSC-Survival and Anoikis Resistance: A ‘Common Receptor Coordinator’ Paradigm

PubMed Central

Herrera, Victoria L.; Decano, Julius L.; Tan, Glaiza A.; Moran, Ann M.; Pasion, Khristine A.; Matsubara, Yuichi; Ruiz-Opazo, Nelson

2014-01-01

A priori, a common receptor induced in tumor microvessels, cancer cells and cancer stem-like cells (CSCs) that is involved in tumor angiogenesis, invasiveness, and CSC anoikis resistance and survival, could underlie contemporaneous coordination of these events rather than assume stochasticity. Here we show that functional analysis of the dual endothelin1/VEGFsignal peptide receptor, DEspR, (formerly named Dear, Chr.4q31.2) supports the putative common receptor paradigm in pancreatic ductal adenocarcinoma (PDAC) and glioblastoma (GBM) selected for their invasiveness, CD133+CSCs, and polar angiogenic features. Unlike normal tissue, DEspR is detected in PDAC and GBM microvessels, tumor cells, and CSCs isolated from PDAC-Panc1 and GBM-U87 cells. DEspR-inhibition decreased angiogenesis, invasiveness, CSC-survival and anoikis resistance in vitro, and decreased Panc1-CSC and U87-CSC xenograft tumor growth, vasculo-angiogenesis and invasiveness in nudenu/nu rats, suggesting that DEspR activation would coordinate these tumor progression events. As an accessible, cell-surface ‘common receptor coordinator’, DEspR-inhibition defines a novel targeted-therapy paradigm for pancreatic cancer and glioblastoma. PMID:24465725

Visualization and contractile activity of cochlear pericytes in the capillaries of the spiral ligament.

PubMed

Dai, Min; Nuttall, Alfred; Yang, Yue; Shi, Xiaorui

2009-08-01

Pericytes, mural cells located on microvessels, are considered to play an important role in the formation of the vasculature and the regulation of local blood flow in some organs. Little is known about the physiology of cochlear pericytes. In order to investigate the function of cochlear pericytes, we developed a method to visualize cochlear pericytes using diaminofluorescein-2 diacetate (DAF-2DA) and intravital fluorescence microscopy. This method can permit the study of the effect of vasoactive agents on pericytes under the in vivo and normal physiological condition. The specificity of the labeling method was verified by the immunofluorescence labeling of pericyte maker proteins such as desmin, neural proteoglycan (NG2), and thymocyte differentiation antigen 1 (Thy-1). Superfused K(+) and Ca(2+) to the cochlear lateral wall resulted in localized constriction of capillaries at pericyte locations both in vivo and in vitro, while there was no obvious change in cochlear capillary diameters with application of the adrenergic neurotransmitter noradrenaline. The method could be an effective way to visualize cochlear pericytes and microvessels and study lateral wall vascular physiology. Moreover, we demonstrate for the first time that cochlear pericytes have contractility, which may be important for regulation of cochlear blood flow.

Vascular endothelial cells express isoforms of protein kinase A inhibitor.

PubMed

Lum, Hazel; Hao, Zengping; Gayle, Dave; Kumar, Priyadarsini; Patterson, Carolyn E; Uhler, Michael D

2002-01-01

The expression and function of the endogenous inhibitor of cAMP-dependent protein kinase (PKI) in endothelial cells are unknown. In this study, overexpression of rabbit muscle PKI gene into endothelial cells inhibited the cAMP-mediated increase and exacerbated thrombin-induced decrease in endothelial barrier function. We investigated PKI expression in human pulmonary artery (HPAECs), foreskin microvessel (HMECs), and brain microvessel endothelial cells (HBMECs). RT-PCR using specific primers for human PKI alpha, human PKI gamma, and mouse PKI beta sequences detected PKI alpha and PKI gamma mRNA in all three cell types. Sequencing and BLAST analysis indicated that forward and reverse DNA strands for PKI alpha and PKI gamma were of >96% identity with database sequences. RNase protection assays showed protection of the 542 nucleotides in HBMEC and HPAEC PKI alpha mRNA and 240 nucleotides in HBMEC, HPAEC, and HMEC PKI gamma mRNA. Western blot analysis indicated that PKI gamma protein was detected in all three cell types, whereas PKI alpha was found in HBMECs. In summary, endothelial cells from three different vascular beds express PKI alpha and PKI gamma, which may be physiologically important in endothelial barrier function.

Estimation of Blood Flow Rates in Large Microvascular Networks

PubMed Central

Fry, Brendan C.; Lee, Jack; Smith, Nicolas P.; Secomb, Timothy W.

2012-01-01

Objective Recent methods for imaging microvascular structures provide geometrical data on networks containing thousands of segments. Prediction of functional properties, such as solute transport, requires information on blood flow rates also, but experimental measurement of many individual flows is difficult. Here, a method is presented for estimating flow rates in a microvascular network based on incomplete information on the flows in the boundary segments that feed and drain the network. Methods With incomplete boundary data, the equations governing blood flow form an underdetermined linear system. An algorithm was developed that uses independent information about the distribution of wall shear stresses and pressures in microvessels to resolve this indeterminacy, by minimizing the deviation of pressures and wall shear stresses from target values. Results The algorithm was tested using previously obtained experimental flow data from four microvascular networks in the rat mesentery. With two or three prescribed boundary conditions, predicted flows showed relatively small errors in most segments and fewer than 10% incorrect flow directions on average. Conclusions The proposed method can be used to estimate flow rates in microvascular networks, based on incomplete boundary data and provides a basis for deducing functional properties of microvessel networks. PMID:22506980

Diabetic Ephrin-B2-Stimulated Peripheral Blood Mononuclear Cells Enhance Poststroke Recovery in Mice.

PubMed

Hilal, Rose; Poittevin, Marine; Pasteur-Rousseau, Adrien; Cogo, Adrien; Mangin, Gabrielle; Chevauché, Marie; Ziat, Yasmine; Vilar, José; Launay, Jean-Marie; Gautier, Jean-François; Broquères-You, Dong; Levy, Bernard I; Merkulova-Rainon, Tatyana; Kubis, Nathalie

2018-01-01

Clinical trials of cell therapy in stroke favor autologous cell transplantation. To date, feasibility studies have used bone marrow-derived mononuclear cells, but harvesting bone marrow cells is invasive thus complicating bedside treatment. We investigated the therapeutic potential of peripheral blood-derived mononuclear cells (PB-MNC) harvested from diabetic patients and stimulated by ephrin-B2 (PB-MNC+) (500,000 cells), injected intravenously 18-24 hours after induced cerebral ischemia in mice. Infarct volume, neurological deficit, neurogenesis, angiogenesis, and inflammation were investigated as were the potential mechanisms of PB-MNC+ cells in poststroke neurorepair. At D3, infarct volume was reduced by 60% and 49% compared to unstimulated PB-MNC and PBS-treated mice, respectively. Compared to PBS, injection of PB-MNC+ increased cell proliferation in the peri-infarct area and the subventricular zone, decreased microglia/macrophage cell density, and upregulated TGF- β expression. At D14, microvessel density was decreased and functional recovery was enhanced compared to PBS-treated mice, whereas plasma levels of BDNF, a major regulator of neuroplasticity, were increased in mice treated with PB-MNC+ compared to the other two groups. Cell transcriptional analysis showed that ephrin-B2 induced phenotype switching of PB-MNC by upregulating genes controlling cell proliferation, inflammation, and angiogenesis, as confirmed by adhesion and Matrigel assays. Conclusions . This feasibility study suggests that PB-MNC+ transplantation poststroke could be a promising approach but warrants further investigation. If confirmed, this rapid, noninvasive bedside cell therapy strategy could be applied to stroke patients at the acute phase.

Diabetic Ephrin-B2-Stimulated Peripheral Blood Mononuclear Cells Enhance Poststroke Recovery in Mice

PubMed Central

Hilal, Rose; Poittevin, Marine; Pasteur-Rousseau, Adrien; Cogo, Adrien; Mangin, Gabrielle; Chevauché, Marie; Ziat, Yasmine; Vilar, José; Launay, Jean-Marie; Gautier, Jean-François; Broquères-You, Dong; Levy, Bernard I.; Merkulova-Rainon, Tatyana

2018-01-01

Clinical trials of cell therapy in stroke favor autologous cell transplantation. To date, feasibility studies have used bone marrow-derived mononuclear cells, but harvesting bone marrow cells is invasive thus complicating bedside treatment. We investigated the therapeutic potential of peripheral blood-derived mononuclear cells (PB-MNC) harvested from diabetic patients and stimulated by ephrin-B2 (PB-MNC+) (500,000 cells), injected intravenously 18–24 hours after induced cerebral ischemia in mice. Infarct volume, neurological deficit, neurogenesis, angiogenesis, and inflammation were investigated as were the potential mechanisms of PB-MNC+ cells in poststroke neurorepair. At D3, infarct volume was reduced by 60% and 49% compared to unstimulated PB-MNC and PBS-treated mice, respectively. Compared to PBS, injection of PB-MNC+ increased cell proliferation in the peri-infarct area and the subventricular zone, decreased microglia/macrophage cell density, and upregulated TGF-β expression. At D14, microvessel density was decreased and functional recovery was enhanced compared to PBS-treated mice, whereas plasma levels of BDNF, a major regulator of neuroplasticity, were increased in mice treated with PB-MNC+ compared to the other two groups. Cell transcriptional analysis showed that ephrin-B2 induced phenotype switching of PB-MNC by upregulating genes controlling cell proliferation, inflammation, and angiogenesis, as confirmed by adhesion and Matrigel assays. Conclusions. This feasibility study suggests that PB-MNC+ transplantation poststroke could be a promising approach but warrants further investigation. If confirmed, this rapid, noninvasive bedside cell therapy strategy could be applied to stroke patients at the acute phase. PMID:29736174

Effects of density on growth, metamorphosis, and survivorship in tadpoles of Scaphiopus holbrooki

DOE Office of Scientific and Technical Information (OSTI.GOV)

Semlitsch, R.D.; Caldwell, J.P.

1982-08-01

Density-dependent aspects of growth, metamorphosis, and survivorship of Scaphiopus holbrooki tadpoles were examined in the laboratory under two experimental regimes. In the first density experiment, the growth index (W) of tadpoles decreased exponentially with density. Mean growth rate varied from 0.023 mL/d at the lowest density to 0.006 mL/d at the highest density. The mean number of days to metamorphic climax was positively associated with the initial density treatment: 27 d at the lowest density to 86 d at the highest density. The body size of tadpoles at metamorphosis showed a concave curvilinear relationship to initial density, indicating tadpoles atmore » the highest densities are apparently capable to growth recovery once released from density stress. The survival of tadpoles decreased exponentially with initial density, from 90% at the lowest density to 20% at the highest initial density. In the second experiment a cross-classified design was used to examine the effects of density and duration of treatment (time) on growth and metamorphosis. Density and time had significant effects on body size at metamorphosis and days to metamorphosis. There was no significant interaction between density and time. These results indicate that the inhibitory effect of density stress varies with the duration of the stress. Scaphiopus holbrooki tadpoles exhibit developmental traits (rapid growth, short larval period, small body size at metamorphosis) that should be favored by natural selection in high density habitats. Dispersability may be a mechanism whereby S. holbrooki can minimize the detrimental effects of density stress.« less

The influence of vegetation cover on debris-flow density during an extreme rainfall in the northern Colorado Front Range

USGS Publications Warehouse

Rengers, Francis K.; McGuire, Luke; Coe, Jeffrey A.; Kean, Jason W.; Baum, Rex L.; Staley, Dennis M.; Godt, Jonathan W.

2016-01-01

We explored regional influences on debris-flow initiation throughout the Colorado Front Range (Colorado, USA) by exploiting a unique data set of more than 1100 debris flows that initiated during a 5 day rainstorm in 2013. Using geospatial data, we examined the influence of rain, hillslope angle, hillslope aspect, and vegetation density on debris-flow initiation. In particular we used a greenness index to differentiate areas of high tree density from grass and bare soil. The data demonstrated an overwhelming propensity for debris-flow initiation on south-facing hillslopes. However, when the debris-flow density was analyzed with respect to total rainfall and greenness we found that most debris flows occurred in areas of high rainfall and low tree density, regardless of hillslope aspect. These results indicate that present-day tree density exerts a stronger influence on debris-flow initiation locations than aspect-driven variations in soil and bedrock properties that developed over longer time scales.

Lateral Root Initiation in Arabidopsis: Developmental Window, Spatial Patterning, Density and Predictability

PubMed Central

DUBROVSKY, J. G.; GAMBETTA, G. A.; HERNÁNDEZ-BARRERA, A.; SHISHKOVA, S.; GONZÁLEZ, I.

2006-01-01

• Background and Aims The basic regulatory mechanisms that control lateral root (LR) initiation are still poorly understood. An attempt is made to characterize the pattern and timing of LR initiation, to define a developmental window in which LR initiation takes place and to address the question of whether LR initiation is predictable. • Methods The spatial patterning of LRs and LR primordia (LRPs) on cleared root preparations were characterized. New measures of LR and LRP densities (number of LRs and/or LRPs divided by the length of the root portions where they are present) were introduced and illustrate the shortcomings of the more customarily used measure through a comparative analysis of the mutant aux1-7. The enhancer trap line J0121 was used to monitor LR initiation in time-lapse experiments and a plasmolysis-based method was developed to determine the number of pericycle cells between successive LRPs. • Key Results LRP initiation occurred strictly acropetally and no de novo initiation events were found between already developed LRs or LRPs. However, LRPs did not become LRs in a similar pattern. The longitudinal spacing of lateral organs was variable and the distance between lateral organs was proportional to the number of cells and the time between initiations of successive LRPs. There was a strong tendency towards alternation in LR initiation between the two pericycle cell files adjacent to the protoxylem poles. LR density increased with time due to the emergence of slowly developing LRPs and appears to be unique for individual Arabidopsis accessions. • Conclusions. In Arabidopsis there is a narrow developmental window for LR initiation, and no specific cell-count or distance-measuring mechanisms have been found that determine the site of successive initiation events. Nevertheless, the branching density and lateral organ density (density of LRs and LRPs) are accession-specific, and based on the latter density the average distance between successive LRs can be predicted. PMID:16390845

Support for the existence of invertible maps between electronic densities and non-analytic 1-body external potentials in non-relativistic time-dependent quantum mechanics

NASA Astrophysics Data System (ADS)

Mosquera, Martín A.

2017-10-01

Provided the initial state, the Runge-Gross theorem establishes that the time-dependent (TD) external potential of a system of non-relativistic electrons determines uniquely their TD electronic density, and vice versa (up to a constant in the potential). This theorem requires the TD external potential and density to be Taylor-expandable around the initial time of the propagation. This paper presents an extension without this restriction. Given the initial state of the system and evolution of the density due to some TD scalar potential, we show that a perturbative (not necessarily weak) TD potential that induces a non-zero divergence of the external force-density, inside a small spatial subset and immediately after the initial propagation time, will cause a change in the density within that subset, implying that the TD potential uniquely determines the TD density. In this proof, we assume unitary evolution of wavefunctions and first-order differentiability (which does not imply analyticity) in time of the internal and external force-densities, electronic density, current density, and their spatial derivatives over the small spatial subset and short time interval.

Dependence of optimal initial density on laser parameters for multi-keV x-ray radiators generated by nanosecond laser-produced underdense plasma

NASA Astrophysics Data System (ADS)

Tu, Shao-yong; Yuan, Yong-teng; Hu, Guang-yue; Miao, Wen-yong; Zhao, Bin; Zheng, Jian; Jiang, Shao-en; Ding, Yong-kun

2016-01-01

Efficient multi-keV x-ray sources can be produced using nanosecond laser pulse-heated middle-Z underdense plasmas generated using gas or foam. Previous experimental results show that an optimal initial target density exists for efficient multi-keV x-ray emission at which the laser ionization wave is supersonic. Here we explore the influence of the laser intensity and the pulse duration on this optimal initial target density via a one-dimensional radiation hydrodynamic simulation. The simulation shows that the optimal initial density is sensitive to both the laser intensity and the pulse duration. However, the speed of the supersonic ionization wave at the end of the laser irradiation is always maintained at 1.5 to 1.7 times that of the ion acoustic wave under the optimal initial density conditions.

Hyperplasia of Pericytes Is One of the Main Characteristics of Microvascular Architecture in Malignant Glioma

PubMed Central

Sun, Huiqin; Guo, Deyu; Su, Yongping; Yu, Dongmei; Wang, Qingliang; Wang, Tao; Zhou, Qing; Ran, Xinze; Zou, Zhongmin

2014-01-01

Objectives To investigate the role of pericytes in constructing the malformed microvessels (MVs) and participating microvascular architecture heterogeneity of glioma. Methods Forty human glioma tissue samples (WHO grade II-IV) were included in present study. Observation of blood vessel patterns, quantitative analysis of endothelial cells (ECs)- and pericyte-labeled MVs and comparison between malignant grades based on single- or double-immunohistochemical staining. The MV number density (MVND), microvascular pericyte number density (MPND), and microvascular pericyte area density (MPAD) were calculated. The expression of PDGFβ was also scored after immunostaining. Results In grade II glioma, most of tumor MVs were the thin-wall CD34+ vessels with near normal morphology. In addition to thin-wall CD34+ MVs, more thick-wall MVs were found in grade III glioma, which often showed α-SMA positive. Most of MVs in grade IV glioma were in the form of plexus, curled cell cords and glomeruloid microvascular proliferation while the α-SMA+ cells were the main components. The MVs usually showed disordered arrangement, loose connection and active cell proliferation as shown by Ki67 and α-SMA coexpression. With the increase of glioma grades, the α-SMA+ MVND, CD34+ MVND and MPND were significantly augmented although the increase of CD34+ MVND but not MPAD was statistically insignificant between grade III and IV. It was interesting that some vessel-like structures only consist of α-SMA+ cells, assuming the guiding role of pericytes in angiogenesis. The expression level of PDGFβ was upregulated and directly correlated with the MPND in different glioma grades. Conclusion Hyperplasia of pericytes was one of the significant characteristics of malignant glioma and locally proliferated pericytes were the main constituent of MVs in high grade glioma. The pathological characteristics of pericytes could be used as indexes of malignant grades of glioma. PMID:25478951

An Unconventional Approach to Reducing Retinal Degeneration After Traumatic Ocular Injury

DTIC Science & Technology

2017-09-01

AWARD NUMBER: W81XWH-15-1-0138 TITLE: An Unconventional Approach to Reducing Retinal Degeneration After Traumatic Ocular Injury PRINCIPAL...2015 - 30 Jun 2017 4. TITLE AND SUBTITLE An Unconventional Approach to Reducing Retinal Degeneration After Traumatic Ocular Injury 5 a . CONTRACT...optic confocal microscope system , test it, and establish protocols for the first successful in vivo retinal microvessel and pericyte advanced

An improved initialization center k-means clustering algorithm based on distance and density

NASA Astrophysics Data System (ADS)

Duan, Yanling; Liu, Qun; Xia, Shuyin

2018-04-01

Aiming at the problem of the random initial clustering center of k means algorithm that the clustering results are influenced by outlier data sample and are unstable in multiple clustering, a method of central point initialization method based on larger distance and higher density is proposed. The reciprocal of the weighted average of distance is used to represent the sample density, and the data sample with the larger distance and the higher density are selected as the initial clustering centers to optimize the clustering results. Then, a clustering evaluation method based on distance and density is designed to verify the feasibility of the algorithm and the practicality, the experimental results on UCI data sets show that the algorithm has a certain stability and practicality.

Pressure effects on the relaxation of an excited nitromethane molecule in an argon bath

NASA Astrophysics Data System (ADS)

Rivera-Rivera, Luis A.; Wagner, Albert F.; Sewell, Thomas D.; Thompson, Donald L.

2015-01-01

Classical molecular dynamics simulations were performed to study the relaxation of nitromethane in an Ar bath (of 1000 atoms) at 300 K and pressures 10, 50, 75, 100, 125, 150, 300, and 400 atm. The molecule was instantaneously excited by statistically distributing 50 kcal/mol among the internal degrees of freedom. At each pressure, 1000 trajectories were integrated for 1000 ps, except for 10 atm, for which the integration time was 5000 ps. The computed ensemble-averaged rotational energy decay is ˜100 times faster than the vibrational energy decay. Both rotational and vibrational decay curves can be satisfactorily fit with the Lendvay-Schatz function, which involves two parameters: one for the initial rate and one for the curvature of the decay curve. The decay curves for all pressures exhibit positive curvature implying the rate slows as the molecule loses energy. The initial rotational relaxation rate is directly proportional to density over the interval of simulated densities, but the initial vibrational relaxation rate decreases with increasing density relative to the extrapolation of the limiting low-pressure proportionality to density. The initial vibrational relaxation rate and curvature are fit as functions of density. For the initial vibrational relaxation rate, the functional form of the fit arises from a combinatorial model for the frequency of nitromethane "simultaneously" colliding with multiple Ar atoms. Roll-off of the initial rate from its low-density extrapolation occurs because the cross section for collision events with L Ar atoms increases with L more slowly than L times the cross section for collision events with one Ar atom. The resulting density-dependent functions of the initial rate and curvature represent, reasonably well, all the vibrational decay curves except at the lowest density for which the functions overestimate the rate of decay. The decay over all gas phase densities is predicted by extrapolating the fits to condensed-phase densities.

Pressure effects on the relaxation of an excited nitromethane molecule in an argon bath

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rivera-Rivera, Luis A.; Wagner, Albert F.; Sewell, Thomas D.

2015-01-07

Classical molecular dynamics simulations were performed to study the relaxation of nitromethane in an Ar bath (of 1000 atoms) at 300 K and pressures 10, 50, 75, 100, 125, 150, 300, and 400 atm. The molecule was instantaneously excited by statistically distributing 50 kcal/mol among the internal degrees of freedom. At each pressure, 1000 trajectories were integrated for 1000 ps, except for 10 atm, for which the integration time was 5000 ps. The computed ensemble-averaged rotational energy decay is similar to 100 times faster than the vibrational energy decay. Both rotational and vibrational decay curves can be satisfactorily fit withmore » the Lendvay-Schatz function, which involves two parameters: one for the initial rate and one for the curvature of the decay curve. The decay curves for all pressures exhibit positive curvature implying the rate slows as the molecule loses energy. The initial rotational relaxation rate is directly proportional to density over the interval of simulated densities, but the initial vibrational relaxation rate decreases with increasing density relative to the extrapolation of the limiting low-pressure proportionality to density. The initial vibrational relaxation rate and curvature are fit as functions of density. For the initial vibrational relaxation rate, the functional form of the fit arises from a combinatorial model for the frequency of nitromethane "simultaneously" colliding with multiple Ar atoms. Roll-off of the initial rate from its low-density extrapolation occurs because the cross section for collision events with L Ar atoms increases with L more slowly than L times the cross section for collision events with one Ar atom. The resulting density-dependent functions of the initial rate and curvature represent, reasonably well, all the vibrational decay curves except at the lowest density for which the functions overestimate the rate of decay. The decay over all gas phase densities is predicted by extrapolating the fits to condensed-phase densities. (C) 2015 AIP Publishing LLC.« less

Pressure effects on the relaxation of an excited nitromethane molecule in an argon bath.

PubMed

Rivera-Rivera, Luis A; Wagner, Albert F; Sewell, Thomas D; Thompson, Donald L

2015-01-07

Classical molecular dynamics simulations were performed to study the relaxation of nitromethane in an Ar bath (of 1000 atoms) at 300 K and pressures 10, 50, 75, 100, 125, 150, 300, and 400 atm. The molecule was instantaneously excited by statistically distributing 50 kcal/mol among the internal degrees of freedom. At each pressure, 1000 trajectories were integrated for 1000 ps, except for 10 atm, for which the integration time was 5000 ps. The computed ensemble-averaged rotational energy decay is ∼100 times faster than the vibrational energy decay. Both rotational and vibrational decay curves can be satisfactorily fit with the Lendvay-Schatz function, which involves two parameters: one for the initial rate and one for the curvature of the decay curve. The decay curves for all pressures exhibit positive curvature implying the rate slows as the molecule loses energy. The initial rotational relaxation rate is directly proportional to density over the interval of simulated densities, but the initial vibrational relaxation rate decreases with increasing density relative to the extrapolation of the limiting low-pressure proportionality to density. The initial vibrational relaxation rate and curvature are fit as functions of density. For the initial vibrational relaxation rate, the functional form of the fit arises from a combinatorial model for the frequency of nitromethane "simultaneously" colliding with multiple Ar atoms. Roll-off of the initial rate from its low-density extrapolation occurs because the cross section for collision events with L Ar atoms increases with L more slowly than L times the cross section for collision events with one Ar atom. The resulting density-dependent functions of the initial rate and curvature represent, reasonably well, all the vibrational decay curves except at the lowest density for which the functions overestimate the rate of decay. The decay over all gas phase densities is predicted by extrapolating the fits to condensed-phase densities.

Pressure effects on the relaxation of an excited nitromethane molecule in an argon bath

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rivera-Rivera, Luis A.; Sewell, Thomas D.; Thompson, Donald L.

2015-01-07

Classical molecular dynamics simulations were performed to study the relaxation of nitromethane in an Ar bath (of 1000 atoms) at 300 K and pressures 10, 50, 75, 100, 125, 150, 300, and 400 atm. The molecule was instantaneously excited by statistically distributing 50 kcal/mol among the internal degrees of freedom. At each pressure, 1000 trajectories were integrated for 1000 ps, except for 10 atm, for which the integration time was 5000 ps. The computed ensemble-averaged rotational energy decay is ∼100 times faster than the vibrational energy decay. Both rotational and vibrational decay curves can be satisfactorily fit with the Lendvay-Schatzmore » function, which involves two parameters: one for the initial rate and one for the curvature of the decay curve. The decay curves for all pressures exhibit positive curvature implying the rate slows as the molecule loses energy. The initial rotational relaxation rate is directly proportional to density over the interval of simulated densities, but the initial vibrational relaxation rate decreases with increasing density relative to the extrapolation of the limiting low-pressure proportionality to density. The initial vibrational relaxation rate and curvature are fit as functions of density. For the initial vibrational relaxation rate, the functional form of the fit arises from a combinatorial model for the frequency of nitromethane “simultaneously” colliding with multiple Ar atoms. Roll-off of the initial rate from its low-density extrapolation occurs because the cross section for collision events with L Ar atoms increases with L more slowly than L times the cross section for collision events with one Ar atom. The resulting density-dependent functions of the initial rate and curvature represent, reasonably well, all the vibrational decay curves except at the lowest density for which the functions overestimate the rate of decay. The decay over all gas phase densities is predicted by extrapolating the fits to condensed-phase densities.« less

Self-focusing and defocusing of Gaussian laser beams in collisional inhomogeneous plasmas with linear density and temperature ramps

NASA Astrophysics Data System (ADS)

Hashemzadeh, M.

2018-01-01

Self-focusing and defocusing of Gaussian laser beams in collisional inhomogeneous plasmas are investigated in the presence of various laser intensities and linear density and temperature ramps. Considering the ponderomotive force and using the momentum transfer and energy equations, the nonlinear electron density is derived. Taking into account the paraxial approximation and nonlinear electron density, a nonlinear differential equation, governing the focusing and defocusing of the laser beam, is obtained. Results show that in the absence of ramps the laser beam is focused between a minimum and a maximum value of laser intensity. For a certain value of laser intensity and initial electron density, the self-focusing process occurs in a temperature range which reaches its maximum at turning point temperature. However, the laser beam is converged in a narrow range for various amounts of initial electron density. It is indicated that the σ2 parameter and its sign can affect the self-focusing process for different values of laser intensity, initial temperature, and initial density. Finally, it is found that although the electron density ramp-down diverges the laser beam, electron density ramp-up improves the self-focusing process.

Particle Size Effects on CL-20 Initiation and Detonation

NASA Astrophysics Data System (ADS)

Valancius, Cole; Bainbridge, Joe; Love, Cody; Richardson, Duane

2017-06-01

Particle size or specific surface area effects on explosives has been of interest to the explosives community for both application and modeling of initiation and detonation. Different particles sizes of CL-20 were used in detonator experiments to determine the effects of particle size on initiation, run-up to steady state detonation, and steady state detonation. Historical tests have demonstrated a direct relationship between particle size and initiation. However, historical tests inadvertently employed density gradients, making it difficult to discern the effects of particle size from the effects of density. Density gradients were removed from these tests using a larger diameter, shorter charge column, allowing for similar loading across different particle sizes. Without the density gradient, the effects of particle size on initiation and detonation are easier to determine. The results of which contrast with historical results, showing particle size does not directly affect initiation threshold.

Appendix C: Automated Vitrification of Mammalian Embryos on a Digital Microfluidic Device.

PubMed

Liu, Jun; Pyne, Derek G; Abdelgawad, Mohamed; Sun, Yu

2017-01-01

This chapter introduces a digital microfluidic device that automates sample preparation for mammalian embryo vitrification. Individual microdroplets manipulated on the microfluidic device were used as microvessels to transport a single mouse embryo through a complete vitrification procedure. Advantages of this approach, compared to manual operation and channel-based microfluidic vitrification, include automated operation, cryoprotectant concentration gradient generation, and feasibility of loading and retrieval of embryos.

In vivo Evaluation of Venular Glycocalyx during Hemorrhagic Shock in Rats using Intravital Microscopy

DTIC Science & Technology

2013-01-01

Brief Communication In vivo evaluation of venular glycocalyx during hemorrhagic shock in rats using intravital microscopy☆,☆☆ Ivo Torres Filho...pathophysiology and tested the hypothesis that hemorrhage causes glycocalyx degrada- tion in cremaster muscle microvessels. We utilized intravital microscopy...bound (Reitsma et al., 2007; Weinbaum et al., 2007). Intravital microscopy has been an invaluable resource for in vivo measurements of critically

Molecular Disruption of Breast Tumor Angiogenesis

DTIC Science & Technology

2004-07-01

human breast cancer . During the period of this grant, we carried out studies to confirm that targeted ablation of PAI- 1 gene expression resulted in a...microvessel endothelial cells. Breast cancer -derived factors (TGF-P, EGF)were found to be important contributors of continued PAI-I expression and long...various culture model systems implicated both urokinase plasminogen activator (uPA) and its fast-acting type-i inhibitor (PAl-l) as necessary to achieve

Deep Photoacoustic/Luminescence/Magnetic Resonance Multimodal Imaging in Living Subjects Using High-Efficiency Upconversion Nanocomposites.

PubMed

Liu, Yu; Kang, Ning; Lv, Jing; Zhou, Zijian; Zhao, Qingliang; Ma, Lingceng; Chen, Zhong; Ren, Lei; Nie, Liming

2016-08-01

A gadolinium-doped multi-shell upconversion nanoparticle under 800 nm excitation is synthesized with a 10-fold fluorescence-intensity enhancement over that under 980 nm. The nanoformulations exhibit excellent photoacoustic/luminescence/magnetic resonance tri-modal imaging capabilities, enabling visualization of tumor morphology and microvessel distribution at a new imaging depth. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Comparison of Retinal Microvessel Blood Flow Velocities Acquired with Two Different Fields of View.

PubMed

Zhou, Jin; Li, Min; Chen, Wan; Yang, Ye; Hu, Liang; Wang, Liang; Jiang, Hong; Wang, Jianhua

2017-01-01

To compare the different retinal blood flow velocities (BFVs) acquired with different fields of view (FOVs) using the retinal function imager (RFI), twenty eyes of twenty healthy subjects were enrolled in the study. Retinal microvessel BFV in the macula was acquired with both a wide FOV (35 degrees, 7.3 × 7.3 mm 2 ) and a commonly used small FOV (20 degrees, 4.3 × 4.3 mm 2 ). The 35-degree FOV was trimmed to be equivalent to the 20-degree FOV to compare the BFVs of the similar FOVs using different settings. With the 35-degree FOV, both retinal arteriolar and venular BFVs were significantly greater than the 20-degree FOV ( P < 0.001). When the 20-degree FOV was compared to the trimmed equivalent 20-degree FOV acquired using the 35-degree FOV, significant BFV differences were found in both the arterioles ( P = 0.029) and venules ( P < 0.001). This is the first study to compare retinal blood flow velocities acquired with different FOVs using RFI. The conversion factor from 35 degrees to 20 degrees is 0.95 for arteriolar BFV and 0.92 for venular BFV, which may be used for comparing BFVs acquired with different FOVs.

Comparison of Retinal Microvessel Blood Flow Velocities Acquired with Two Different Fields of View

PubMed Central

Zhou, Jin; Chen, Wan; Yang, Ye; Hu, Liang; Wang, Liang

2017-01-01

To compare the different retinal blood flow velocities (BFVs) acquired with different fields of view (FOVs) using the retinal function imager (RFI), twenty eyes of twenty healthy subjects were enrolled in the study. Retinal microvessel BFV in the macula was acquired with both a wide FOV (35 degrees, 7.3 × 7.3 mm2) and a commonly used small FOV (20 degrees, 4.3 × 4.3 mm2). The 35-degree FOV was trimmed to be equivalent to the 20-degree FOV to compare the BFVs of the similar FOVs using different settings. With the 35-degree FOV, both retinal arteriolar and venular BFVs were significantly greater than the 20-degree FOV (P < 0.001). When the 20-degree FOV was compared to the trimmed equivalent 20-degree FOV acquired using the 35-degree FOV, significant BFV differences were found in both the arterioles (P = 0.029) and venules (P < 0.001). This is the first study to compare retinal blood flow velocities acquired with different FOVs using RFI. The conversion factor from 35 degrees to 20 degrees is 0.95 for arteriolar BFV and 0.92 for venular BFV, which may be used for comparing BFVs acquired with different FOVs. PMID:28758031

Optimal occlusion uniformly partitions red blood cells fluxes within a microvascular network

PubMed Central

Tu, Shenyinying; Liu, Yu-Hsiu; Savage, Van M.; Hsiai, Tzung K.; Roper, Marcus

2017-01-01

In animals, gas exchange between blood and tissues occurs in narrow vessels, whose diameter is comparable to that of a red blood cell. Red blood cells must deform to squeeze through these narrow vessels, transiently blocking or occluding the vessels they pass through. Although the dynamics of vessel occlusion have been studied extensively, it remains an open question why microvessels need to be so narrow. We study occlusive dynamics within a model microvascular network: the embryonic zebrafish trunk. We show that pressure feedbacks created when red blood cells enter the finest vessels of the trunk act together to uniformly partition red blood cells through the microvasculature. Using mathematical models as well as direct observation, we show that these occlusive feedbacks are tuned throughout the trunk network to prevent the vessels closest to the heart from short-circuiting the network. Thus occlusion is linked with another open question of microvascular function: how are red blood cells delivered at the same rate to each micro-vessel? Our analysis shows that tuning of occlusive feedbacks increase the total dissipation within the network by a factor of 11, showing that uniformity of flows rather than minimization of transport costs may be prioritized by the microvascular network. PMID:29244812

L-arginine as dietary supplement for improving microvascular function.

PubMed

Melik, Ziva; Zaletel, Polona; Virtic, Tina; Cankar, Ksenija

2017-01-01

Reduced availability of nitric oxide leads to dysfunction of endothelium which plays an important role in the development of cardiovascular diseases. The aim of the present study was to determine whether the dietary supplement L-arginine improves the endothelial function of microvessels by increasing nitric oxide production. We undertook experiments on 51 healthy male volunteers, divided into 4 groups based on their age and physical activity since regular physical activity itself increases endothelium-dependent vasodilation. The skin laser Doppler flux was measured in the microvessels before and after the ingestion of L-arginine (0.9 g). The endothelium-dependent vasodilation was assessed by acetylcholine iontophoresis and the endothelium-independent vasodilation by sodium nitroprusside iontophoresis. In addition, we measured endothelium-dependent and endothelium-independent vasodilation in 81 healthy subjects divided into four age groups. After the ingestion of L-arginine, the endothelium-dependent vasodilation in the young trained subjects increased (paired t-test, p < 0.05), while in the other groups it remained the same. There were no differences in the endothelium-independent vasodilation after ingestion of L-arginine. With aging endothelium-independent vasodilation decreased while endothelium-dependent vasodilation remained mainly unchanged. Obtained results demonstrated that a single dose of L-arginine influences endothelium-dependent vasodilation predominantly in young, trained individuals.

In vivo flow cytometry and time-resolved near-IR angiography and lymphography

NASA Astrophysics Data System (ADS)

Galanzha, Ekaterina I.; Tuchin, Valery V.; Brock, Robert W.; Zharov, Vladimir P.

2007-05-01

Integration of photoacoustic and photothermal techniques with high-speed, high-resolution transmission and fluorescence microscopy shows great potential for in vivo flow cytometry and indocyanine green (ICG) near-infrared (IR) angiography of blood and lymph microvessels. In particular, the capabilities of in vivo flow cytometry using rat mesentery and nude mouse ear models are demonstrated for real-time quantitative detection of circulating and migrating individual blood and cancer cells in skin, mesentery, lymph nodes, liver, kidney; studying vascular dynamics with a focus on lymphatics; monitoring cell traffic between blood and lymph systems; high-speed imaging of cell deformability in flow; and label-free real-time monitoring of single cell extravasation from blood vessel lumen into tissue. As presented, the advantages of ICG IR-angiography include estimation of time resolved dye dynamics (appearance and clearance) in blood and lymph microvessels using fluorescent and photoacoustic modules of the integrated technique. These new approaches are important for monitoring and quantifying metastatic and apoptotic cells; comparative measurements of plasma and cell velocities; analysis of immune responses; monitoring of circulating macromolecules, chylomicrons, bacteria, viruses and nanoparticles; molecular imaging. In the future, we believe that the integrated technique presented will have great potential for translation to early disease diagnoses (e.g. cancer) or assessment of innovative therapeutic interventions in humans.

Localization of the ANG II type 2 receptor in the microcirculation of skeletal muscle

NASA Technical Reports Server (NTRS)

Nora, E. H.; Munzenmaier, D. H.; Hansen-Smith, F. M.; Lombard, J. H.; Greene, A. S.; Cowley, A. W. (Principal Investigator)

1998-01-01

Only functional studies have suggested the presence of the ANG II type 2 (AT2) receptor in the microcirculation. To determine the distribution of this receptor in the rat skeletal muscle microcirculation, a polyclonal rabbit anti-rat antiserum was developed and used for immunohistochemistry and Western blot analysis. The antiserum was prepared against a highly specific and antigenic AT2-receptor synthetic peptide and was validated by competition and sensitivity assays. Western blot analysis demonstrated a prominent, single band at approximately 40 kDa in cremaster and soleus muscle. Immunohistochemical analysis revealed a wide distribution of AT2 receptors throughout the skeletal muscle microcirculation in large and small microvessels. Microanatomic studies displayed an endothelial localization of the AT2 receptor, whereas dual labeling with smooth muscle alpha-actin also showed colocalization of the AT2 receptor with vascular smooth muscle cells. Other cells associated with the microvessels also stained positive for AT2 receptors. Briefly, this study confirms previous functional data and localizes the AT2 receptor to the microcirculation. These studies demonstrate that the AT2 receptor is present on a variety of vascular cell types and that it is situated in a fashion that would allow it to directly oppose ANG II type 1 receptor actions.

Neutral amino acid transport across brain microvessel endothelial cell monolayers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Audus, K.L.; Borchardt, R.T.

1986-03-01

Brain microvessel endothelial cells (BMEC) which form the blood-brain barrier (BBB) possess an amino acid carrier specific for large neutral amino acids (LNAA). The carrier is important for facilitating the delivery of nutrient LNAA's and centrally acting drugs that are LNAA's, to the brain. Bovine BMEC's were isolated and grown up to complete monolayers on regenerated cellulose-membranes in primary culture. To study the transendothelial transport of leucine, the monolayers were placed in a side-by-side diffusion cell, and transport across the monolayers followed with (/sup 3/H)-leucine. The transendothelial transport of leucine in this in vitro model was determined to be bidirectional,more » and time-, temperature-, and concentration-dependent. The transport of leucine was saturable and the apparent K/sub m/ and V/sub max/, 0.18 mM and 6.3 nmol/mg/min, respectively. Other LNAA's, including the centrally acting drugs, ..cap alpha..-methyldopa, L-DOPA, ..cap alpha..-methyl-tyrosine, and baclofen, inhibited leucine transport. The leucine carrier was also found to be stereospecific and not sensitive to inhibitors of active transport. These results are consistent with previous in vitro and in vivo studies. Primary cultures of BMEC's appear to be a potentially important tool for investigating at the cellular level, the transport mechanisms of the BBB.« less

Tissue factor is an angiogenic-specific receptor for factor VII-targeted immunotherapy and photodynamic therapy.

PubMed

Hu, Zhiwei; Cheng, Jijun; Xu, Jie; Ruf, Wolfram; Lockwood, Charles J

2017-02-01

Identification of target molecules specific for angiogenic vascular endothelial cells (VEC), the inner layer of pathological neovasculature, is critical for discovery and development of neovascular-targeting therapy for angiogenesis-dependent human diseases, notably cancer, macular degeneration and endometriosis, in which vascular endothelial growth factor (VEGF) plays a central pathophysiological role. Using VEGF-stimulated vascular endothelial cells (VECs) isolated from microvessels, venous and arterial blood vessels as in vitro angiogenic models and unstimulated VECs as a quiescent VEC model, we examined the expression of tissue factor (TF), a membrane-bound receptor on the angiogenic VEC models compared with quiescent VEC controls. We found that TF is specifically expressed on angiogenic VECs in a time-dependent manner in microvessels, venous and arterial vessels. TF-targeted therapeutic agents, including factor VII (fVII)-IgG1 Fc and fVII-conjugated photosensitizer, can selectively bind angiogenic VECs, but not the quiescent VECs. Moreover, fVII-targeted photodynamic therapy can selectively and completely eradicate angiogenic VECs. We conclude that TF is an angiogenic-specific receptor and the target molecule for fVII-targeted therapeutics. This study supports clinical trials of TF-targeted therapeutics for the treatment of angiogenesis-dependent diseases such as cancer, macular degeneration and endometriosis.

Monitoring of small lymphatics function under different impact on animal model by integrated optical imaging

NASA Astrophysics Data System (ADS)

Galanzha, Ekaterina I.; Tuchin, Valery V.; Chowdhury, Parimal; Zharov, Vladimir P.

2004-08-01

The digital transmission microscopy is very informative, noninvasive for vessels, simple and available method for studying and measuring lymph microvessels function in vivo. Rat mesentery can use as promising animal model of lymph microvessels in vivo. Such imaging system allowed visualizing the entire lymphangion (with input and output valves), its wall, lymphatic valves, lymph flow as well as single cells in flow; obtaining anew basic information on lymph microcirculation and quantitative data on lymphatic function including indexes of phasic contractions and valve function, the quantitative parameters of lymph-flow velocity. Rat mesentery is good model to create different types of lymphedemas in acute and chronic experiments. The obtained data revealed that significant edema started immediately after lymph node dissection in one-half of cases and was accompanied by lymphatic disturbances. The greatest degree of edema was found after 1 week. After 4 weeks, the degree of edema sometimes decreased, but functional lymphatic disturbances progressed. Nicotine had significant direct dose-dependent effect on microlymphatic function at the acute local application, but the same dose of this drug was not effect on microcirculation in chronic intoxication. Despite yielding interesting data, transmittance microscopy had some limitations when applied to microcirculation studies. The problems could be solved at the application of integrated measuring technique.

Lens-free computational imaging of capillary morphogenesis within three-dimensional substrates

NASA Astrophysics Data System (ADS)

Weidling, John; Isikman, Serhan O.; Greenbaum, Alon; Ozcan, Aydogan; Botvinick, Elliot

2012-12-01

Endothelial cells cultured in three-dimensional (3-D) extracellular matrices spontaneously form microvessels in response to soluble and matrix-bound factors. Such cultures are common for the study of angiogenesis and may find widespread use in drug discovery. Vascular networks are imaged over weeks to measure the distribution of vessel morphogenic parameters. Measurements require micron-scale spatial resolution, which for light microscopy comes at the cost of limited field-of-view (FOV) and shallow depth-of-focus (DOF). Small FOVs and DOFs necessitate lateral and axial mechanical scanning, thus limiting imaging throughput. We present a lens-free holographic on-chip microscopy technique to rapidly image microvessels within a Petri dish over a large volume without any mechanical scanning. This on-chip method uses partially coherent illumination and a CMOS sensor to record in-line holographic images of the sample. For digital reconstruction of the measured holograms, we implement a multiheight phase recovery method to obtain phase images of capillary morphogenesis over a large FOV (24 mm2) with ˜1.5 μm spatial resolution. On average, measured capillary length in our method was within approximately 2% of lengths measured using a 10× microscope objective. These results suggest lens-free on-chip imaging is a useful toolset for high-throughput monitoring and quantitative analysis of microvascular 3-D networks.

Dabigatran abrogates brain endothelial cell permeability in response to thrombin

PubMed Central

Hawkins, Brian Thomas; Gu, Yu-Huan; Izawa, Yoshikane; del Zoppo, Gregory John

2015-01-01

Atrial fibrillation (AF) increases the risk and severity of thromboembolic stroke. Generally, antithrombotic agents increase the hemorrhagic risk of thromboembolic stroke. However, significant reductions in thromboembolism and intracerebral hemorrhage have been shown with the antithrombin dabigatran compared with warfarin. As thrombin has been implicated in microvessel injury during cerebral ischemia, we hypothesized that dabigatran decreases the risk of intracerebral hemorrhage by direct inhibition of the thrombin-mediated increase in cerebral endothelial cell permeability. Primary murine brain endothelial cells (mBECs) were exposed to murine thrombin before measuring permeability to 4-kDa fluorescein isothiocyanate-dextran. Thrombin increased mBEC permeability in a concentration-dependent manner, without significant endothelial cell death. Pretreatment of mBECs with dabigatran completely abrogated the effect of thrombin on permeability. Neither the expressions of the endothelial cell β1-integrins nor the tight junction protein claudin-5 were affected by thrombin exposure. Oxygen-glucose deprivation (OGD) also increased permeability; this effect was abrogated by treatment with dabigatran, as was the additive effect of thrombin and OGD on permeability. Taken together, these results indicate that dabigatran could contribute to a lower risk of intracerebral hemorrhage during embolism-associated ischemia from AF by protection of the microvessel permeability barrier from local thrombin challenge. PMID:25669912

Spectral imaging based in vivo model system for characterization of tumor microvessel response to vascular targeting agents

NASA Astrophysics Data System (ADS)

Wankhede, Mamta

Functional vasculature is vital for tumor growth, proliferation, and metastasis. Many tumor-specific vascular targeting agents (VTAs) aim to destroy this essential tumor vasculature to induce indirect tumor cell death via oxygen and nutrition deprivation. The tumor angiogenesis-inhibiting anti-angiogenics (AIs) and the established tumor vessel targeting vascular disrupting agents (VDAs) are the two major players in the vascular targeting field. Combination of VTAs with conventional therapies or with each other, have been shown to have additive or supra-additive effects on tumor control and treatment. Pathophysiological changes post-VTA treatment in terms of structural and vessel function changes are important parameters to characterize the treatment efficacy. Despite the abundance of information regarding these parameters acquired using various techniques, there remains a need for a quantitative, real-time, and direct observation of these phenomenon in live animals. Through this research we aspired to develop a spectral imaging based mouse tumor system for real-time in vivo microvessel structure and functional measurements for VTA characterization. A model tumor system for window chamber studies was identified, and then combinatorial effects of VDA and AI were characterized in model tumor system. (Full text of this dissertation may be available via the University of Florida Libraries web site. Please check http://www.uflib.ufl.edu/etd.html)

Engineering of a Biomimetic Pericyte-Covered 3D Microvascular Network.

PubMed

Kim, Jaerim; Chung, Minhwan; Kim, Sudong; Jo, Dong Hyun; Kim, Jeong Hun; Jeon, Noo Li

2015-01-01

Pericytes enveloping the endothelium play an important role in the physiology and pathology of microvessels, especially in vessel maturation and stabilization. However, our understanding of fundamental pericyte biology is limited by the lack of a robust in vitro model system that allows researchers to evaluate the interactions among multiple cell types in perfusable blood vessels. The present work describes a microfluidic platform that can be used to investigate interactions between pericytes and endothelial cells (ECs) during the sprouting, growth, and maturation steps of neovessel formation. A mixture of ECs and pericytes was attached to the side of a pre-patterned three dimensional fibrin matrix and allowed to sprout across the matrix. The effects of intact coverage and EC maturation by the pericytes on the perfused EC network were confirmed using a confocal microscope. Compared with EC monoculture conditions, EC-pericyte co-cultured vessels showed a significant reduction in diameter, increased numbers of junctions and branches and decreased permeability. In response to biochemical factors, ECs and pericytes in the platform showed the similar features with previous reports from in vivo experiments, thus reflect various pathophysiological conditions of in vivo microvessels. Taken together, these results support the physiological relevancy of our three-dimensional microfluidic culture system but also that the system can be used to screen drug effect on EC-pericyte biology.

Remodeling of the skeletal muscle microcirculation increases resistance to perfusion in obese Zucker rats.

PubMed

Frisbee, Jefferson C

2003-07-01

Whereas previous studies have demonstrated that the development of syndrome X in obese Zucker rats (OZR) is associated with impaired arteriolar reactivity to vasoactive stimuli, additional results from these studies indicate that the passive diameter of skeletal muscle arterioles is reduced in OZR versus lean Zucker rats (LZR). On the basis of these prior observations, the present study evaluated structural alterations to the skeletal muscle microcirculation as potential contributors to an elevated vascular resistance. Isolated skeletal muscle resistance arterioles exhibited a reduced passive diameter at all levels of intralumenal pressure and a left-shifted stress-strain curve in OZR versus LZR, indicative of structural remodeling of individual arterioles. Histological analyses using Griffonia simplicifolia I lectin-stained sections of skeletal muscle demonstrated reduced microvessel density (rarefaction) in OZR versus LZR, suggesting remodeling of entire microvascular networks. Finally, under maximally dilated conditions, constant flow-perfused skeletal muscle of OZR exhibited significant elevations in perfusion pressure versus LZR, indicative of an increased resistance to perfusion within the microcirculation. These data suggest that developing structural alterations to the skeletal muscle microcirculation in OZR result in elevated vascular resistance, which may, acting in concert with impaired arteriolar reactivity, contribute to blunted active hyperemic responses and compromised performance of in situ skeletal muscle with elevated metabolic demand.

IL-17 Promotes Angiogenic Factors IL-6, IL-8, and Vegf Production via Stat1 in Lung Adenocarcinoma.

PubMed

Huang, Qi; Duan, Limin; Qian, Xin; Fan, Jinshuo; Lv, Zhilei; Zhang, Xiuxiu; Han, Jieli; Wu, Feng; Guo, Mengfei; Hu, Guorong; Du, Jiao; Chen, Caiyun; Jin, Yang

2016-11-07

Inflammation and angiogenesis are two hallmarks of carcinoma. The proinflammatory cytokine interleukin-17 (IL-17) facilitates angiogenesis in lung cancer; however, the underlying mechanism is not fully understood. In this study, tumour microvessel density (MVD) was positively associated with IL-17, interleukin-6 (IL-6), interleukin-8 (IL-8), and vascular endothelial cell growth factor (VEGF) expression in human lung adenocarcinoma tissues, and it was increased in tumour tissues of A549-IL-17 cell-bearing nude mice. Importantly, positive correlations were also detected between IL-17 expression and IL-6, IL-8 and VEGF expression in human lung adenocarcinoma tissues. Furthermore, IL-6, IL-8 and VEGF production, as well as STAT1 phosphorylation, were increased in tumour tissues of A549-IL-17 cell-bearing nude mice in vivo and in A549 and H292 cells following IL-17 stimulation in vitro. In addition, STAT1 knockdown using an inhibitor and siRNA attenuated the IL-17-mediated increases in IL-6, IL-8 and VEGF expression in A549 and H292 cells. In conclusion, IL-17 may promote the production of the angiogenic inducers IL-6, IL-8 and VEGF via STAT1 signalling in lung adenocarcinoma.

The urokinase receptor-derived cyclic peptide [SRSRY] suppresses neovascularization and intravasation of osteosarcoma and chondrosarcoma cells.

PubMed

Ingangi, Vincenzo; Bifulco, Katia; Yousif, Ali Munaim; Ragone, Concetta; Motti, Maria Letizia; Rea, Domenica; Minopoli, Michele; Botti, Giovanni; Scognamiglio, Giuseppe; Fazioli, Flavio; Gallo, Michele; De Chiara, Annarosaria; Arra, Claudio; Grieco, Paolo; Carriero, Maria Vincenza

2016-08-23

The receptor for the urokinase-type plasminogen activator (uPAR) is a widely recognized master regulator of cell migration and uPAR88-92 is the minimal sequence required to induce cell motility and angiogenesis by interacting with the formyl peptide receptor type 1 (FPR1). In this study, we present evidence that the cyclization of the uPAR88-92 sequence generates a new potent inhibitor of migration, and extracellular matrix invasion of human osteosarcoma and chondrosarcoma cells expressing comparable levels of FPR1 on cell surface. In vitro, the cyclized peptide [SRSRY] prevents formation of capillary-like tubes by endothelial cells co-cultured with chondrosarcoma cells and trans-endothelial migration of osteosarcoma and chondrosarcoma cells. When chondrosarcoma cells were subcutaneously injected in nude mice, tumor size, intra-tumoral microvessel density and circulating tumor cells in blood samples collected before the sacrifice, were significantly reduced in animals treated daily with i.p-administration of 6 mg/Kg [SRSRY] as compared to animals treated with vehicle only. Our findings indicate that [SRSRY] prevents three key events occurring during the metastatic process of osteosarcoma and chondrosarcoma cells: the extracellular matrix invasion, the formation of a capillary network and the entry into bloodstream.

The urokinase receptor-derived cyclic peptide [SRSRY] suppresses neovascularization and intravasation of osteosarcoma and chondrosarcoma cells

PubMed Central

Ingangi, Vincenzo; Bifulco, Katia; Yousif, Ali Munaim; Ragone, Concetta; Motti, Maria Letizia; Rea, Domenica; Minopoli, Michele; Botti, Giovanni; Scognamiglio, Giuseppe; Fazioli, Flavio; Gallo, Michele; De Chiara, Annarosaria; Arra, Claudio; Grieco, Paolo; Carriero, Maria Vincenza

2016-01-01

The receptor for the urokinase-type plasminogen activator (uPAR) is a widely recognized master regulator of cell migration and uPAR88–92 is the minimal sequence required to induce cell motility and angiogenesis by interacting with the formyl peptide receptor type 1 (FPR1). In this study, we present evidence that the cyclization of the uPAR88–92 sequence generates a new potent inhibitor of migration, and extracellular matrix invasion of human osteosarcoma and chondrosarcoma cells expressing comparable levels of FPR1 on cell surface. In vitro, the cyclized peptide [SRSRY] prevents formation of capillary-like tubes by endothelial cells co-cultured with chondrosarcoma cells and trans-endothelial migration of osteosarcoma and chondrosarcoma cells. When chondrosarcoma cells were subcutaneously injected in nude mice, tumor size, intra-tumoral microvessel density and circulating tumor cells in blood samples collected before the sacrifice, were significantly reduced in animals treated daily with i.p-administration of 6 mg/Kg [SRSRY] as compared to animals treated with vehicle only. Our findings indicate that [SRSRY] prevents three key events occurring during the metastatic process of osteosarcoma and chondrosarcoma cells: the extracellular matrix invasion, the formation of a capillary network and the entry into bloodstream. PMID:27323409

Expansion of microvascular networks in vivo by phthalimide neovascular factor 1 (PNF1)

PubMed Central

Wieghaus, Kristen A.; Nickerson, Meghan M.; Aronin, Caren E. Petrie; Sefcik, Lauren S.; Price, Richard J.; Paige, Mikell A.; Brown, Milton L.; Botchwey, Edward A.

2010-01-01

Phthalimide neovascular factor (PNF1, formerly SC-3-149) is a potent stimulator of proangiogenic signaling pathways in endothelial cells. In this study, we evaluated the in vivo effects of sustained PNF1 release to promote ingrowth and expansion of microvascular networks surrounding biomaterial implants. The dorsal skinfold window chamber was used to evaluate the structural remodeling response of the local microvasculature. PNF1 was released from poly(lactic-co-glycolic acid) (PLAGA) films, and a transport model was utilized to predict PNF1 penetration into the surrounding tissue. PNF1 significantly expanded microvascular networks within a 2 mm radius from implants after 3 and 7 days by increasing microvessel length density and lumenal diameter of local arterioles and venules. Staining of histological sections with CD11b showed enhanced recruitment of circulating white blood cells, including monocytes, which are critical for the process of vessel enlargement through arteriogenesis. As PNF1 has been shown to modulate MT1-MMP, a facilitator of CCL2 dependent leukocyte transmigration, aspects of window chamber experiments were repeated in CCR2−/− (CCL2 receptor) mouse chimeras to more fully explore the critical nature of monocyte recruitment on the therapeutic benefits of PNF1 function in vivo. PMID:18804278

Interleukin-8 is a prognostic indicator in human hilar cholangiocarcinoma

PubMed Central

Sun, Qi; Li, Fanni; Sun, Fengkai; Niu, Jun

2015-01-01

Interleukin-8 (IL-8), matrix metalloproteinase-9 (MMP-9) and neovascularization have been implicated to be associated with biological processes, especially cancer progression. However, few studies have investigated the role of IL-8 in human hilar cholangiocarcinoma. In this study we detected the expression of IL-8 combined with MMP-9 and microvessel density (MVD) in hilar cholangiocarcinoma to evaluate their clinicopathological significance and prognostic value. A total of 62 patients with hilar cholangiocarcinoma who underwent curative surgery were enrolled in this study. The expression of IL-8, MMP-9 and MVD were examined immunohistochemically. The correlation of IL-8 with MMP-9 expression, MVD, clinicopathological features and survival time of patients were then analyzed. Expression of IL-8 was observed in 56.5% tumors, which was related to advanced TNM stage (P = 0.026) and tumor recurrence (P = 0.018). IL-8 had a positive correlation with MMP-9 expression and MVD. Furthermore, patients with high IL-8 expression had a significantly shorter overall survival than those with low IL-8 expression (P = 0.01). Multivariate analysis confirmed IL-8 as an independent prognostic factor (P = 0.005). In conclusion, IL-8 expression significantly correlated with MMP-9 expression and MVD, and IL-8 was a valuable prognostic factor for human hilar cholangiocarcinoma. PMID:26339407

Endothelial RSPO3 Controls Vascular Stability and Pruning through Non-canonical WNT/Ca(2+)/NFAT Signaling.

PubMed

Scholz, Beate; Korn, Claudia; Wojtarowicz, Jessica; Mogler, Carolin; Augustin, Iris; Boutros, Michael; Niehrs, Christof; Augustin, Hellmut G

2016-01-11

The WNT signaling enhancer R-spondin3 (RSPO3) is prominently expressed in the vasculature. Correspondingly, embryonic lethality of Rspo3-deficient mice is caused by vessel remodeling defects. Yet the mechanisms underlying vascular RSPO3 function remain elusive. Inducible endothelial Rspo3 deletion (Rspo3-iECKO) resulted in perturbed developmental and tumor vascular remodeling. Endothelial cell apoptosis and vascular pruning led to reduced microvessel density in Rspo3-iECKO mice. Rspo3-iECKO mice strikingly phenocopied the non-canonical WNT signaling-induced vascular defects of mice deleted for the WNT secretion factor Evi/Wls. An endothelial screen for RSPO3 and EVI/WLS co-regulated genes identified Rnf213, Usp18, and Trim30α. RNF213 targets filamin A and NFAT1 for proteasomal degradation attenuating non-canonical WNT/Ca(2+) signaling. Likewise, USP18 and TRIM5α inhibited NFAT1 activation. Consequently, NFAT protein levels were decreased in endothelial cells of Rspo3-iECKO mice and pharmacological NFAT inhibition phenocopied Rspo3-iECKO mice. The data identify endothelial RSPO3-driven non-canonical WNT/Ca(2+)/NFAT signaling as a critical maintenance pathway of the remodeling vasculature. Copyright © 2016 Elsevier Inc. All rights reserved.

Expansion of microvascular networks in vivo by phthalimide neovascular factor 1 (PNF1).

PubMed

Wieghaus, Kristen A; Nickerson, Meghan M; Petrie Aronin, Caren E; Sefcik, Lauren S; Price, Richard J; Paige, Mikell A; Brown, Milton L; Botchwey, Edward A

2008-12-01

Phthalimide neovascular factor (PNF1, formerly SC-3-149) is a potent stimulator of proangiogenic signaling pathways in endothelial cells. In this study, we evaluated the in vivo effects of sustained PNF1 release to promote ingrowth and expansion of microvascular networks surrounding biomaterial implants. The dorsal skinfold window chamber was used to evaluate the structural remodeling response of the local microvasculature. PNF1 was released from poly(lactic-co-glycolic acid) (PLAGA) films, and a transport model was utilized to predict PNF1 penetration into the surrounding tissue. PNF1 significantly expanded microvascular networks within a 2mm radius from implants after 3 and 7 days by increasing microvessel length density and lumenal diameter of local arterioles and venules. Staining of histological sections with CD11b showed enhanced recruitment of circulating white blood cells, including monocytes, which are critical for the process of vessel enlargement through arteriogenesis. As PNF1 has been shown to modulate MT1-MMP, a facilitator of CCL2 dependent leukocyte transmigration, aspects of window chamber experiments were repeated in CCR2(-/-) (CCL2 receptor) mouse chimeras to more fully explore the critical nature of monocyte recruitment on the therapeutic benefits of PNF1 function in vivo.

Polymeric micelles encapsulating fisetin improve the therapeutic effect in colon cancer.

PubMed

Chen, Yishan; Wu, Qinjie; Song, Linjiang; He, Tao; Li, Yuchen; Li, Ling; Su, Weijun; Liu, Lei; Qian, Zhiyong; Gong, Changyang

2015-01-14

The natural flavonoid fisetin (3,3',4',7-tetrahydroxyflavone) was discovered to possess antitumor activity, revealing its potential value in future chemotherapy. However, its poor water solubility makes it difficult for intravenous administration. In this study, the monomethyl poly(ethylene glycol)-poly(ε-caprolactone) (MPEG-PCL) copolymer was applied to prepare nanoassemblies of fisetin by a self-assembly procedure. The prepared fisetin micelles gained a mean particle size of 22 ± 3 nm, polydisperse index of 0.163 ± 0.032, drug loading of 9.88 ± 0.14%, and encapsulation efficiency of 98.53 ± 0.02%. Compared with free fisetin, fisetin micelles demonstrated a sustained and prolonged in vitro release behavior, as well as enhanced cytotoxicity, cellular uptake, and fisetin-induced apoptosis in CT26 cells. As for in vivo studies, fisetin micelles were more competent for suppressing tumor growth and prolonging survival time than free fisetin in the subcutaneous CT26 tumor model. Furthermore, histological analysis, terminal deoxynucleotidyl transferase-mediated nick-end labeling assay, immunohistochemical detection of Ki-67, and microvessel density detection were conducted, demonstrating that fisetin micelles gained increased tumor apoptosis induction, proliferation suppression, and antiangiogenesis activities. In conclusion, we have successfully produced a MPEG-PCL-based nanocarrier encapsulating fisetin with enhanced antitumor activity.

Reduced cognitive function, increased blood-brain-barrier transport and inflammatory responses, and altered brain metabolites in LDLr -/-and C57BL/6 mice fed a western diet

PubMed Central

Lee, Linda L.; Puchowicz, Michelle; Golub, Mari S.; Befroy, Douglas E.; Wilson, Dennis W.; Anderson, Steven; Cline, Gary; Bini, Jason; Borkowski, Kamil; Knotts, Trina A.; Rutledge, John C.

2018-01-01

Recent work suggests that diet affects brain metabolism thereby impacting cognitive function. Our objective was to determine if a western diet altered brain metabolism, increased blood-brain barrier (BBB) transport and inflammation, and induced cognitive impairment in C57BL/6 (WT) mice and low-density lipoprotein receptor null (LDLr -/-) mice, a model of hyperlipidemia and cognitive decline. We show that a western diet and LDLr -/- moderately influence cognitive processes as assessed by Y-maze and radial arm water maze. Also, western diet significantly increased BBB transport, as well as microvessel factor VIII in LDLr -/- and microglia IBA1 staining in WT, both indicators of activation and neuroinflammation. Interestingly, LDLr -/- mice had a significant increase in 18F- fluorodeoxyglucose uptake irrespective of diet and brain 1H-magnetic resonance spectroscopy showed increased lactate and lipid moieties. Metabolic assessments of whole mouse brain by GC/MS and LC/MS/MS showed that a western diet altered brain TCA cycle and β-oxidation intermediates, levels of amino acids, and complex lipid levels and elevated proinflammatory lipid mediators. Our study reveals that the western diet has multiple impacts on brain metabolism, physiology, and altered cognitive function that likely manifest via multiple cellular pathways. PMID:29444171

"Deep-media culture condition" promoted lumen formation of endothelial cells within engineered three-dimensional tissues in vitro.

PubMed

Sekiya, Sachiko; Shimizu, Tatsuya; Yamato, Masayuki; Okano, Teruo

2011-03-01

In the field of tissue engineering, the induction of microvessels into tissues is an important task because of the need to overcome diffusion limitations of oxygen and nutrients within tissues. Powerful methods to create vessels in engineered tissues are needed for creating real living tissues. In this study, we utilized three-dimensional (3D) highly cell dense tissues fabricated by cell sheet technology. The 3D tissue constructs are close to living-cell dense tissue in vivo. Additionally, creating an endothelial cell (EC) network within tissues promoted neovascularization promptly within the tissue after transplantation in vivo. Compared to the conditions in vivo, however, common in vitro cell culture conditions provide a poor environment for creating lumens within 3D tissue constructs. Therefore, for determining adequate conditions for vascularizing engineered tissue in vitro, our 3D tissue constructs were cultured under a "deep-media culture conditions." Compared to the control conditions, the morphology of ECs showed a visibly strained cytoskeleton, and the density of lumen formation within tissues increased under hydrostatic pressure conditions. Moreover, the increasing expression of vascular endothelial cadherin in the lumens suggested that the vessels were stabilized in the stimulated tissues compared with the control. These findings suggested that deep-media culture conditions improved lumen formation in engineered tissues in vitro.

In vivo bioluminescence imaging validation of a human biopsy-derived orthotopic mouse model of glioblastoma multiforme.

PubMed

Jarzabek, Monika A; Huszthy, Peter C; Skaftnesmo, Kai O; McCormack, Emmet; Dicker, Patrick; Prehn, Jochen H M; Bjerkvig, Rolf; Byrne, Annette T

2013-05-01

Glioblastoma multiforme (GBM), the most aggressive brain malignancy, is characterized by extensive cellular proliferation, angiogenesis, and single-cell infiltration into the brain. We have previously shown that a xenograft model based on serial xenotransplantation of human biopsy spheroids in immunodeficient rodents maintains the genotype and phenotype of the original patient tumor. The present work further extends this model for optical assessment of tumor engraftment and growth using bioluminescence imaging (BLI). A method for successful lentiviral transduction of the firefly luciferase gene into multicellular spheroids was developed and implemented to generate optically active patient tumor cells. Luciferase-expressing spheroids were injected into the brains of immunodeficient mice. BLI photon counts and tumor volumes from magnetic resonance imaging (MRI) were correlated. Luciferase-expressing tumors recapitulated the histopathologic hallmarks of human GBMs and showed proliferation rates and microvessel density counts similar to those of wild-type xenografts. Moreover, we detected widespread invasion of luciferase-positive tumor cells in the mouse brains. Herein we describe a novel optically active model of GBM that closely mimics human pathology with respect to invasion, angiogenesis, and proliferation indices. The model may thus be routinely used for the assessment of novel anti-GBM therapeutic approaches implementing well-established and cost-effective optical imaging strategies.

Prognostic significance of XRCC4 expression in hepatocellular carcinoma

PubMed Central

Huang, Xiao-Ying; Yao, Jin-Guang; Wang, Chao; Wei, Zhong-Hong; Ma, Yun; Wu, Xue-Min; Luo, Chun-Ying; Xia, Qiang; Long, Xi-Dai

2017-01-01

Background Our previous investigations have shown that the variants of X-ray repair complementing 4 (XRCC4) may be involved in hepatocellular carcinoma (hepatocarcinoma) tumorigenesis. This study aimed to investigate the possible prognostic significance of XRCC4 expression for hepatocarcinoma patients and possible value for the selection of transarterial chemoembolization (TACE) treatment. Materials and Methods We conducted a hospital-based retrospective analysis (including 421 hepatocarcinoma cases) to analyze the effects of XRCC4 on hepatocarcinoma prognosis and TACE. The levels of XRCC4 expression were tested using immunohistochemistry. The sensitivity of cancer cells to anti-cancer drug doxorubicin was evaluated using the half-maximal inhibitory concentration (IC50). Results XRCC4 expression was significantly correlated with pathological features including tumor stage, liver cirrhosis, and micro-vessel density. XRCC4 expression was an independent prognostic factor of hepatocarcinoma, and TACE treatments had no effects on prognosis of hepatocarcinoma patients with high XRCC4 expression. More intriguingly, TACE improved the prognosis of hepatocarcinoma patients with low XRCC4 expression. Functionally, XRCC4 overexpression increased while XRCC4 knockdown reduced the IC50 of cancer cells to doxorubicin. Conclusions These results suggest that XRCC4 may be an independent prognostic factor for hepatocarcinoma patients, and that decreasing XRCC4 expression may be beneficial for post-operative adjuvant TACE treatment in hepatocarcinoma. PMID:29152133

Decursin and decursinol angelate inhibit VEGF-induced angiogenesis via suppression of the VEGFR-2-signaling pathway.

PubMed

Jung, Myung Hwan; Lee, Sun Hee; Ahn, Eun-Mi; Lee, You Mie

2009-04-01

Inhibition of angiogenesis is an attractive approach for the treatment of angiogenic diseases, such as cancer. Vascular endothelial growth factor (VEGF) is one of the most important activators of angiogenesis and interacts with the high-affinity tyrosine kinase receptors, VEGFR-1 and VEGFR-2. The pyranocoumarin compounds decursin and decursinol angelate isolated from the herb, Angelica gigas, are known to possess potent anti-inflammatory activities. However, little is known about their antiangiogenic activity or their underlying mechanisms. Here, we show the antiangiogenic effects of decursin and decursinol angelate using in vitro assays and in vivo animal experiments. Decursin and decursinol angelate inhibited VEGF-induced angiogenic processes in vitro, including proliferation, migration and tube formation of human umbilical vein endothelial cells. Decursin and decursinol angelate significantly suppressed neovessel formation in chick chorioallantoic membrane and tumor growth in a mouse model. The microvessel density in tumors treated with decursin for 14 days was significantly decreased compared with a vehicle control group. Decursin and decursinol angelate inhibited VEGF-induced phosphorylation of VEGFR-2, extracellular signal-regulated kinases and c-Jun N-terminal kinase mitogen-activated protein kinases. Taken together, these results demonstrate that decursin and decursinol angelate are novel candidates for inhibition of VEGF-induced angiogenesis.

In vivo anti-cancer activity of Korean Angelica gigas and its major pyranocoumarin decursin.

PubMed

Lee, Hyo Jeong; Lee, Hyo Jung; Lee, Eun Ok; Lee, Jae Ho; Lee, Kuen Sung; Kim, Kwan Hyun; Kim, Sung-Hoon; Lü, Junxuan

2009-01-01

We have reported that a 10-herbal traditional formula containing Korean Angelica gigas Nakai (AGN) exerts potent anti-cancer efficacy and identified decursin and decursinol angelate (DA) from AGN as novel anti-androgens. Here, we determined whether AGN would exert in vivo anti-cancer activity and whether decursin or DA could account for its efficacy. The AGN ethanol extract was tested against the growth of mouse Lewis lung cancer (LLC) allograft in syngenic mice or human PC-3 and DU145 prostate cancer xenograft in immunodeficient mice. The pharmacokinetics of decursin and DA were determined. The AGN extract significantly inhibited LLC allograft growth (30 mg/kg) and PC-3 and DU145 xenograft growth (100 mg/kg) without affecting the body weight of the host mice. Biomarker analyses revealed decreased cell proliferation (Ki67, PCNA), decreased angiogenesis (VEGF, microvessel density) and increased apoptosis (TUNEL, cPARP) in treated tumors. Decursin and DA injected intraperitoneally were rapidly hydrolyzed to decursinol. Decursinol and decursin at 50 mg/kg inhibited LLC allograft growth to the same extent, comparable to 30 mg AGN/kg. Therefore the AGN extract possessed significant in vivo anti-cancer activity, but decursin and DA only contributed moderately to that activity, most likely through decursinol.

[Are there alternative forms of therapy in breast carcinoma? Status and perspectives for the treatment of metastasized breast carcinoma].

PubMed

Unger, C; Marmé, D

1995-03-28

The emergence of new cytotoxic agents and techniques for treatment of systemic disease as single modalities or in combination with irradiation and surgery will impact on the use of such agents in the management of systemic breast cancer. Metastatic breast carcinoma, unlike other solid tumors, is highly responsive to chemotherapy, response rates of 50 to 70% have been reported consistently, although there has not been a significant improvement on long-term survival of these patients in the last ten years. New therapeutic approaches include cytotoxic and hormonal agents, growth and differentiation factors, monoclonal antibodies, hematopoietic stem cell support, conquest of tumor cell resistance by MDR-modulation, genetic manipulation, identification of new targets on the tumor surface, synthesis of target-oriented designer-drugs and inhibition of tumor angiogenesis. In breast cancer the tumor growth correlates with vascularization and angiogenesis. Tumor angiogenesis is stimulated by the vascular endothelial growth factor (VEGF). Microvessel density is a significant predictor of survival among node-negative women, who are at risk for having occult metastases at presentation. These patients could then be given systemic adjuvant therapy. Animal experiments show promising inhibition of tumor growth in nude mice after application of antibodies against VEGF. Other methods of manipulation of molecular mechanisms of angiogenesis are under investigation.

Vector-based RNA interference against vascular endothelial growth factor-A significantly limits vascularization and growth of prostate cancer in vivo.

PubMed

Wannenes, Francesca; Ciafré, Silvia Anna; Niola, Francesco; Frajese, Gaetano; Farace, Maria Giulia

2005-12-01

RNA interference technology is emerging as a very potent tool to obtain a cellular knockdown of a desired gene. In this work we used vector-based RNA interference to inhibit vascular endothelial growth factor (VEGF) expression in prostate cancer in vitro and in vivo. We demonstrated that transduction with a plasmid carrying a small interfering RNA targeting all isoforms of VEGF, dramatically impairs the expression of this growth factor in the human prostate cancer cell line PC3. As a consequence, PC3 cells loose their ability to induce one of the fundamental steps of angiogenesis, namely the formation of a tube-like network in vitro. Most importantly, our "therapeutic" vector is able to impair tumor growth rate and vascularization in vivo. We show that a single injection of naked plasmid in developing neoplastic mass significantly decreases microvessel density in an androgen-refractory prostate xenograft and is able to sustain a long-term slowing down of tumor growth. In conclusion, our results confirm the basic role of VEGF in the angiogenic development of prostate carcinoma, and suggest that the use of our vector-based RNA interference approach to inhibit angiogenesis could be an effective tool in view of future gene therapy applications for prostate cancer.

Effect of Jianweiyuyang granule on gastric ulcer recurrence and expression of VEGF mRNA in the healing process of gastric ulcer in rats.

PubMed

Dai, Xing-Ping; Li, Jia-Bang; Liu, Zhao-Qian; Ding, Xiang; Huang, Cheng-Hui; Zhou, Bing

2005-09-21

To investigate the effect of Jianweiyuyang (JWYY) granule on gastric ulcer recurrence and its mechanism in the treatment of gastric ulcer in rats. Gastric ulcer in rats was induced according to Okeba's method with minor modification and the recurrence model was induced by IL-1beta. The expression of vascular endothelial growth factor mRNA (VEGF mRNA) was examined by reverse transcription polymerase chain reaction in gastric ulcer and microvessel density (MVD) adjacent to the ulcer margin was examined by immunohistochemistry. MVD was higher in the JWYY treatment group (14.0+/-2.62) compared with the normal, model and ranitidine treatment groups (2.2+/-0.84, 8.8+/-0.97, 10.4+/-0.97) in rats (P<0.01). The expression level of VEGF mRNA in gastric tissues during the healing process of JWYY treatment group rats significantly increased compared with other groups (normal group: 0.190+/-0.019, model group: 0.642+/-0.034, ranitidine group: 0.790+/-0.037, P<0.01). JWYY granules can stimulate angiogenesis and enhance the expression of VEGF mRNA in gastric ulcer rats. This might be the mechanism for JWYY accelerating the ulcer healing, and preventing the recurrence of gastric ulcer.

Chinese Herbal Medicine Xueshuantong Enhances Cerebral Blood Flow and Improves Neural Functions in Alzheimer's Disease Mice.

PubMed

Huang, Yangmei; Guo, Baihong; Shi, Bihua; Gao, Qingtao; Zhou, Qiang

2018-01-01

Reduced cerebral blood flow in Alzheimer's disease (AD) may occur in early AD, which contributes to the pathogenesis and/or pathological progression of AD. Reversing this deficit may have therapeutic potential. Certain traditional Chinese herbal medicines (e.g., Saponin and its major component Xueshuantong [XST]) increase blood flow in humans, but whether they could be effective in treating AD patients has not been tested. We found that systemic XST injection elevated cerebral blood flow in APP/PS1 transgenic mice using two-photon time-lapse imaging in the same microvessels before and after injection. Subchronic XST treatment led to improved spatial learning and memory and motor performance in the APP/PS1 mice, suggesting improved neural plasticity and functions. Two-photon time lapse imaging of the same plaques revealed a reduction in plaque size after XST treatment. In addition, western blots experiments showed that XST treatment led to reduced processing of amyloid-β protein precursor (AβPP) and enhanced clearance of amyloid-β (Aβ) without altering the total level of AβPP. We also found increased synapse density in the immediate vicinity of amyloid plaques, suggesting enhanced synaptic function. We conclude that targeting cerebral blood flow can be an effective strategy in treating AD.

Suppression of tumor-induced angiogenesis by taspine isolated from Radix et Rhizoma Leonticis and its mechanism of action in vitro.

PubMed

Zhang, Yanmin; He, Langchong; Meng, Liang; Luo, Wenjuan; Xu, Xuemei

2008-04-08

The present study was to demonstrate the effect of taspine isolated from Radix et Rhizoma Leonticis on tumor angiogenesis and its mechanism of action. The anti-angiogenic effect in vivo was evaluated on chicken chorioallantoic membrane (CAM) neovascularisation model and CAM transplantation tumor model. Taspine exerted inhibitory influence on CAM angiogenesis and the growth and microvessel density (MVD) of CAM transplantation tumor at concentrations of 0.5-2μg/egg. The mechanism was demonstrated through detecting vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) protein secretion by enzyme-linked immunosorbent assay (ELISA), as well as mRNA expression of VEGF, Flt-1 and Flk-1/KDR by reverse transcription-polymerase chain reaction (RT-PCR). The results showed that taspine down-regulated the VEGF and bFGF secretion in human non-small cell lung cancer cell (A549 cell) and human umbilical vein endothelial cell (HUVEC), and the VEGF and Flk-1/KDR mRNA expression in HUVEC. Additionally, the effect of taspine on HUVEC migration was detected with the method of cell scrape. The result indicated that taspine inhibited HUVEC migration in a dose-dependent manner. These findings suggest that taspine might be a promising candidate as angiogenesis inhibitors.

Metformin promotes focal angiogenesis and neurogenesis in mice following middle cerebral artery occlusion.

PubMed

Liu, Yanqun; Tang, Guanghui; Zhang, Zhijun; Wang, Yongting; Yang, Guo-Yuan

2014-09-05

Current studies demonstrated that metformin is not only a hypoglycemic drug, but also a neuro-protective agent. However, the effect of metformin during ischemic brain injury is unclear. The aim of the present study is to explore the effect of metformin during ischemic brain injury. Adult male CD1 mice underwent 90min transient middle cerebral artery occlusion. Metformin (200mg/kg) was given at the time of reperfusion daily until sacrifice. Results showed that metformin treatment significantly reduced ischemia-induced brain atrophy volume compared to the control (p<0.05). Immunostaining results showed that the microvessel density in the peri-focal region of metformin treated mice was greatly increased compared to the control (p<0.05). Similarly, the numbers of BrdU+/DCX+ and nestin+ cells in the subventricular zone were increased in metformin treated mice compared to the control (p<0.05). Furthermore, we demonstrated that metformin treatment activated AMPK signaling pathway and promoted eNOS phosphorylation. Thus, we concluded that metformin promoted focal angiogenesis and neurogenesis and attenuated ischemia-induced brain injury in mice after middle cerebral artery occlusion, suggesting that metformin is a potential new drug for ischemic stroke therapy. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Physiological responses to acid stress by Saccharomyces cerevisiae when applying high initial cell density

PubMed Central

2016-01-01

High initial cell density is used to increase volumetric productivity and shorten production time in lignocellulosic hydrolysate fermentation. Comparison of physiological parameters in high initial cell density cultivation of Saccharomyces cerevisiae in the presence of acetic, formic, levulinic and cinnamic acids demonstrated general and acid-specific responses of cells. All the acids studied impaired growth and inhibited glycolytic flux, and caused oxidative stress and accumulation of trehalose. However, trehalose may play a role other than protecting yeast cells from acid-induced oxidative stress. Unlike the other acids, cinnamic acid did not cause depletion of cellular ATP, but abolished the growth of yeast on ethanol. Compared with low initial cell density, increasing initial cell density reduced the lag phase and improved the bioconversion yield of cinnamic acid during acid adaptation. In addition, yeast cells were able to grow at elevated concentrations of acid, probable due to the increase in phenotypic cell-to-cell heterogeneity in large inoculum size. Furthermore, the specific growth rate and the specific rates of glucose consumption and metabolite production were significantly lower than at low initial cell density, which was a result of the accumulation of a large fraction of cells that persisted in a viable but non-proliferating state. PMID:27620460

Effect of initial densities in the lattice Boltzmann model for non-ideal fluid with curved interface

NASA Astrophysics Data System (ADS)

Gong, Jiaming; Oshima, Nobuyuki

2017-06-01

The effect of initial densities in a free energy based two-phase-flow lattice Boltzmann method for non-ideal fluids with a curved interface was investigated in the present work. To investigate this effect, the initial densities in the liquid and gas phases coming from the saturation points and the equilibrium state were adopted in the simulation of a static droplet in an open and a closed system. For the purpose of simplicity and easier comparison, the closed system is fabricated by the implementation of the periodic boundary condition at the inlet and outlet of a gas channel, and the open system is fabricated by the implementation of a constant flux boundary condition at the inlet and a free-out boundary condition at the outlet of the same gas channel. By comparing the simulation results from the two types of initial densities in the open and closed systems, it is proven that the commonly used saturation initial densities setting is the reason for droplet mass and volume variation which occurred in the simulation, particularly in the open system with a constant flux boundary condition. Such problems are believed to come from the curvature effect of the surface tension and can be greatly reduced by adopting the initial densities in the two phases from equilibrium state.

Acute microcirculatory response to nicotine in frog web.

PubMed

Horimoto, M; Koyama, T

1982-01-01

Acute effects of nicotine (NC) on the microcirculation of frog webs were studied by measuring the blood flow velocity in arterioles, and by determining the diameter of both arterioles and venules. Simultaneous recordings of the ventricular pressure and heart rate were obtained in order to compute the vascular resistance and to interpret the changes in microcirculation. The web of right hindlimb was immersed in a solution of NC (2.6 to 3.4 mg/ml) for 4 min. Blood flow velocity in web arterioles of left hindlimb was measured by means of a laser Doppler microscope. Internal diameters of web microvessels were determined using a micrometer on the ocular lens of the microscope. Mean flow velocity (MV) and pulsatile amplitude (PA) were calculated from the pulsatile flow-velocity contour for each vessel. Both MV and PA were increased after the immersion of the web in NC solution. Although the magnitude of the increment in MV was proportional to that in ventricular pressure, the vasodilation of both arterioles and venules and the flow rate in arterioles higher than the initial state continued even after the ventricular pressure had returned to the initial control value. Calculation of the relative change in vascular resistance in web arterioles following NC administration suggested a vasodilator response to NC. Furthermore, our results indicate that sufficient NC can be absorbed across the web epithelium to produce a systemic vascular response when the concentration of NC in the bathing solution is 2.6 mg/ml.

Improvement of skin-graft survival after autologous transplantation of adipose-derived stem cells in rats.

PubMed

Zografou, A; Tsigris, C; Papadopoulos, O; Kavantzas, N; Patsouris, E; Donta, I; Perrea, D

2011-12-01

Skin grafts are frequently used for a variety of indications in plastic and reconstructive surgery. Their necrosis is a common complication, while different therapies have been proposed. Currently, adipose-derived stem cells (ASCs) hold great promise for their angiogenic potential and role during tissue repair. In this study, autologous transplantation of ASCs was used in skin grafts in rats to determine if it increases angiogenesis, skin-graft survival and wound healing. ASCs were isolated, cultured, labelled with fluorescent dye and injected under full-thickness skin grafts in 10 rats (group 1), while 10 others served as controls (group 2). Skin grafts were analysed after 1 week. Collagen's framework was assessed with Masson's trichrome stain and angiogenesis with von Willebrand factor (vWF) immunohistochemistry. In addition, immunohistochemical staining intensity of vascular endothelial growth factor (VEGF) and transforming growth factor b3 (TGFb3) was assessed in all grafts. Mean area of graft necrosis was significantly less in group 1 than in group 2 (6.12% vs. 32.62%, p<0.01). Statistically significant increase of microvessel density, collagen density, VEGF and TGFb3 expression was noted in group 1 compared with group 2 (all: p<0.01). These findings suggest that autologous ASCs transplantation increases full-thickness skin-graft survival and shows promise for use in skin-graft surgery. This might be both due to in situ differentiation of ASCs into endothelial cells and increased secretion by ASCs of growth factors, such as VEGF and TGFb3 that enhance angiogenesis and wound healing. Copyright © 2011 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Sprint interval and endurance training are equally effective in increasing muscle microvascular density and eNOS content in sedentary males

PubMed Central

Cocks, Matthew; Shaw, Christopher S; Shepherd, Sam O; Fisher, James P; Ranasinghe, Aaron M; Barker, Thomas A; Tipton, Kevin D; Wagenmakers, Anton J M

2013-01-01

Sprint interval training (SIT) has been proposed as a time efficient alternative to endurance training (ET) for increasing skeletal muscle oxidative capacity and improving certain cardiovascular functions. In this study we sought to make the first comparisons of the structural and endothelial enzymatic changes in skeletal muscle microvessels in response to ET and SIT. Sixteen young sedentary males (age 21 ± SEM 0.7 years, BMI 23.8 ± SEM 0.7 kg m−2) were randomly assigned to 6 weeks of ET (40–60 min cycling at ∼65%, 5 times per week) or SIT (4–6 Wingate tests, 3 times per week). Muscle biopsies were taken from the m. vastus lateralis before and following 60 min cycling at 65% to measure muscle microvascular endothelial eNOS content, eNOS serine1177 phosphorylation, NOX2 content and capillarisation using quantitative immunofluorescence microscopy. Whole body insulin sensitivity, arterial stiffness and blood pressure were also assessed. ET and SIT increased skeletal muscle microvascular eNOS content (ET 14%; P < 0.05, SIT 36%; P < 0.05), with a significantly greater increase observed following SIT (P < 0.05). Sixty minutes of moderate intensity exercise increased eNOS ser1177 phosphorylation in all instances (P < 0.05), but basal and post-exercise eNOS ser1177 phosphorylation was lower following both training modes. All microscopy measures of skeletal muscle capillarisation (P < 0.05) were increased with SIT or ET, while neither endothelial nor sarcolemmal NOX2 was changed. Both training modes reduced aortic stiffness and increased whole body insulin sensitivity (P < 0.05). In conclusion, in sedentary males SIT and ET are effective in improving muscle microvascular density and eNOS protein content. PMID:22946099

Effects of Combined Simultaneous and Sequential Endostar and Cisplatin Treatment in a Mice Model of Gastric Cancer Peritoneal Metastases.

PubMed

Jia, Lin; Ren, Shuguang; Li, Tao; Wu, Jianing; Zhou, Xinliang; Zhang, Yan; Wu, Jianhua; Liu, Wei

2017-01-01

Objective . Aimed to study the effects of endostar and cisplatin using an in vivo imaging system (IVIS) in a model of peritoneal metastasis of gastric cancer. Methods . NUGC-4 gastric cancer cells transfected with luciferase gene (NUGC-4-Luc) were injected i.p. into nude mice. One week later, mice were randomly injected i.p.: group 1, cisplatin (d1-3) + endostar (d4-7); group 2, endostar (d1-4) + cisplatin (d5-7); group 3, endostar + cisplatin d1, 4, and 7; group 4, saline for two weeks. One week after the final administration, mice were sacrificed. Bioluminescent data, microvessel density (MVD), and lymphatic vessel density (LVD) were analyzed. Results . Among the four groups, there were no significant differences in the weights and in the number of cancer cell photons on days 1 and 8 ( P > 0.05). On day 15, the numbers in groups 3 and 1 were less than that in group 2 ( P < 0.05). On day 21, group 3 was significantly less than group 2 ( P < 0.05). MVD of group 4 was less than that of groups 1 and 2 ( P < 0.01). There was no significant difference between groups 2 and 3 ( P > 0.05) or in LVD number among the four groups ( P > 0.05). Conclusions . IVIS® was more useful than weight, volume of ascites, and number of peritoneal nodules. The simultaneous group was superior to sequential groups in killing cancer cells and inhibiting vascular endothelium. Cisplatin-endostar was superior to endostar-cisplatin in killing cancer cells, while the latter in inhibiting peritoneal vascular endothelium.

Effects of laser power density and initial grain size in laser shock punching of pure copper foil

NASA Astrophysics Data System (ADS)

Zheng, Chao; Zhang, Xiu; Zhang, Yiliang; Ji, Zhong; Luan, Yiguo; Song, Libin

2018-06-01

The effects of laser power density and initial grain size on forming quality of holes in laser shock punching process were investigated in the present study. Three different initial grain sizes as well as three levels of laser power densities were provided, and then laser shock punching experiments of T2 copper foil were conducted. Based upon the experimental results, the characteristics of shape accuracy, fracture surface morphology and microstructures of punched holes were examined. It is revealed that the initial grain size has a noticeable effect on forming quality of holes punched by laser shock. The shape accuracy of punched holes degrades with the increase of grain size. As the laser power density is enhanced, the shape accuracy can be improved except for the case in which the ratio of foil thickness to initial grain size is approximately equal to 1. Compared with the fracture surface morphology in the quasistatic loading conditions, the fracture surface after laser shock can be divided into three zones including rollover, shearing and burr. The distribution of the above three zones strongly relates with the initial grain size. When the laser power density is enhanced, the shearing depth is not increased, but even diminishes in some cases. There is no obvious change of microstructures with the enhancement of laser power density. However, while the initial grain size is close to the foil thickness, single-crystal shear deformation may occur, suggesting that the ratio of foil thickness to initial grain size has an important impact on deformation behavior of metal foil in laser shock punching process.

Experimental test of an eco-evolutionary dynamic feedback loop between evolution and population density in the green peach aphid.

PubMed

Turcotte, Martin M; Reznick, David N; Daniel Hare, J

2013-05-01

An eco-evolutionary feedback loop is defined as the reciprocal impacts of ecology on evolutionary dynamics and evolution on ecological dynamics on contemporary timescales. We experimentally tested for an eco-evolutionary feedback loop in the green peach aphid, Myzus persicae, by manipulating initial densities and evolution. We found strong evidence that initial aphid density alters the rate and direction of evolution, as measured by changes in genotype frequencies through time. We also found that evolution of aphids within only 16 days, or approximately three generations, alters the rate of population growth and predicts density compared to nonevolving controls. The impact of evolution on population dynamics also depended on density. In one evolution treatment, evolution accelerated population growth by up to 10.3% at high initial density or reduced it by up to 6.4% at low initial density. The impact of evolution on population growth was as strong as or stronger than that caused by a threefold change in intraspecific density. We found that, taken together, ecological condition, here intraspecific density, alters evolutionary dynamics, which in turn alter concurrent population growth rate (ecological dynamics) in an eco-evolutionary feedback loop. Our results suggest that ignoring evolution in studies predicting population dynamics might lead us to over- or underestimate population density and that we cannot predict the evolutionary outcome within aphid populations without considering population size.

Mechanisms of radiation-induced normal tissue toxicity and implications for future clinical trials

PubMed Central

Jenrow, Kenneth A.; Brown, Stephen L.

2014-01-01

To summarize current knowledge regarding mechanisms of radiation-induced normal tissue injury and medical countermeasures available to reduce its severity. Advances in radiation delivery using megavoltage and intensity-modulated radiation therapy have permitted delivery of higher doses of radiation to well-defined tumor target tissues. Injury to critical normal tissues and organs, however, poses substantial risks in the curative treatment of cancers, especially when radiation is administered in combination with chemotherapy. The principal pathogenesis is initiated by depletion of tissue stem cells and progenitor cells and damage to vascular endothelial microvessels. Emerging concepts of radiation-induced normal tissue toxicity suggest that the recovery and repopulation of stromal stem cells remain chronically impaired by long-lived free radicals, reactive oxygen species, and pro-inflammatory cytokines/chemokines resulting in progressive damage after radiation exposure. Better understanding the mechanisms mediating interactions among excessive generation of reactive oxygen species, production of pro-inflammatory cytokines and activated macrophages, and role of bone marrow-derived progenitor and stem cells may provide novel insight on the pathogenesis of radiation-induced injury of tissues. Further understanding the molecular signaling pathways of cytokines and chemokines would reveal novel targets for protecting or mitigating radiation injury of tissues and organs. PMID:25324981

[Influence of rosiglitazone and all-trans-retinoic acid on angiogenesis and growth of myeloma xenograft in nude mice].

PubMed

Huang, Hai-wen; Chen, Ping; Li, Bing-zong; Fu, Jin-xiang; Li, Jun; Zhang, Xiao-hui; Liu, Rui; Fan, Yin-yin; Zhang, Hong; Chow, Howard C H; Leung, Anska Y H; Liang, Raymond

2012-09-01

To observe the effect of rosiglitazone (RGZ) and all-trans-retinoic acid (ATRA) on the growth of myeloma xenograft in nude mice and to explore the influence of RGZ and ATRA on VEGF expression and angiogenesis in the tumor. VEGF gene expression in myeloma cell line U266 cells was analyzed by semi-quantitative RT-PCR after incubation with RGZ, ATRA, or RGZ + ATRA for 24 h. Myeloma xenograft was established by subcutaneous injection of 10(7) U266 cells in the scapula area of 4-week old nude mice. 7 days later, the nude mice were administered with RGZ, ATRA or RGZ + ATRA, respectively, by intraperitoneal injection once every day for 21 days. The control mice were given equal volume of normal saline instead of the drug. On the 21(st) day of treatment, the mice were sacrificed and the tumors were taken off, and the tumor volume and weight were measured. The tumors were examined by histopathology with HE staining, and microvessel density (MVD), CD34 and VEGF expression in the tumors were analyzed by immunohistochemical staining. VEGF mRNA was highly expressed in U266 cells and was decreased in a dose-dependent manner after incubation with RGZ. The VEGF mRNA level was further more decreased after RGZ + ATRA treatment. Xenografts of U266 cells were developed in all nude mice. The volume and weight of xenografts in the RGZ group were (785 ± 262) mm(3) and (1748 ± 365) mg, respectively, significantly lower than those of the control group (both P < 0.01). More significant inhibition was in the RGZ + ATRA group, (154 ± 89) mm(3) and (626 ± 102) mg, respectively, both were P < 0.05 vs. the RGZ group. RGZ inhibited the angiogenesis in U266 xenografts and immunohistochemical staining showed that the tumor MVD and VEGF expression were significantly decreased by RGZ treatment, and further more inhibited in the RGZ + ATRA group. VEGF protein was expressed in all xenografts in the nude mice. Its immunohistochemical staining intensity was 2.20 ± 0.40 in the control group, significantly higher than that of 1.48 ± 0.37 in the RGZ group (P < 0.01), and that of RGZ + ATRA group was 0.58 ± 0.26, further significantly lower than that of the RGZ group (P < 0.01). CD34 was expressed in all xenografts, most highly in the control group and lowest in the RGZ + ATRA group. The microvessel density (MVD) was highest in the control group (56.4 ± 15.2), significantly lower in the RGZ group (44.6 ± 11.2) (P < 0.05), and lowest in the RGZ + ATRA group (21.5 ± 8.6, P < 0.01). The growth of myeloma cells can also be inhibited by RGZ and ATRA in nude mice in vivo. In addition to differentiation and apoptosis induction, RGZ can inhibit the formation of myeloma xenograft probably also through the downregulation of VEGF expression and subsequent angiogenesis.

Polymer brush covalently attached to OH-functionalized mica surface via surface-initiated ATRP: control of grafting density and polymer chain length.

PubMed

Lego, Béatrice; François, Marion; Skene, W G; Giasson, Suzanne

2009-05-05

The controlled grafting density of poly(tert-butyl acrylate) was studied on OH-activated mica substrates via surface-initiated atom-transfer radical polymerization (ATRP). By properly adjusting parameters such as the immobilization reaction time and the concentration of an ATRP initiator, a wide range of initiator surface coverages and hence polymer densities on mica were possible. The covalently immobilized initiator successfully promoted the polymerization of tert-butyl acrylate on mica surfaces. The resulting polymer layer thickness was measured by AFM using a step-height method. Linear relationships of the polymer thickness with respect to the molecular weight of the free polymer and with respect to the monomer conversion were observed, suggesting that ATRP is well controlled and relatively densely end-grafted layers were obtained. The polymer grafting density controlled by adjusting the initiator surface coverage was confirmed by the polymer layer swelling capacity and film thickness measurements.

SURFplus Model Calibration for PBX 9502

DOE Office of Scientific and Technical Information (OSTI.GOV)

Menikoff, Ralph

2017-12-06

The SURFplus reactive burn model is calibrated for the TATB based explosive PBX 9502 at three initial temperatures; hot (75 C), ambient (23 C) and cold (-55 C). The CJ state depends on the initial temperature due to the variation in the initial density and initial specific energy of the PBX reactants. For the reactants, a porosity model for full density TATB is used. This allows the initial PBX density to be set to its measured value even though the coeffcient of thermal expansion for the TATB and the PBX differ. The PBX products EOS is taken as independent ofmore » the initial PBX state. The initial temperature also affects the sensitivity to shock initiation. The model rate parameters are calibrated to Pop plot data, the failure diameter, the limiting detonation speed just above the failure diameters, and curvature effect data for small curvature.« less

Global existence and large time asymptotic behavior of strong solutions to the Cauchy problem of 2D density-dependent Navier–Stokes equations with vacuum

NASA Astrophysics Data System (ADS)

Lü, Boqiang; Shi, Xiaoding; Zhong, Xin

2018-06-01

We are concerned with the Cauchy problem of the two-dimensional (2D) nonhomogeneous incompressible Navier–Stokes equations with vacuum as far-field density. It is proved that if the initial density decays not too slow at infinity, the 2D Cauchy problem of the density-dependent Navier–Stokes equations on the whole space admits a unique global strong solution. Note that the initial data can be arbitrarily large and the initial density can contain vacuum states and even have compact support. Furthermore, we also obtain the large time decay rates of the spatial gradients of the velocity and the pressure, which are the same as those of the homogeneous case.

A multiphase model for three-dimensional tumor growth

NASA Astrophysics Data System (ADS)

Sciumè, G.; Shelton, S.; Gray, W. G.; Miller, C. T.; Hussain, F.; Ferrari, M.; Decuzzi, P.; Schrefler, B. A.

2013-01-01

Several mathematical formulations have analyzed the time-dependent behavior of a tumor mass. However, most of these propose simplifications that compromise the physical soundness of the model. Here, multiphase porous media mechanics is extended to model tumor evolution, using governing equations obtained via the thermodynamically constrained averaging theory. A tumor mass is treated as a multiphase medium composed of an extracellular matrix (ECM); tumor cells (TCs), which may become necrotic depending on the nutrient concentration and tumor phase pressure; healthy cells (HCs); and an interstitial fluid for the transport of nutrients. The equations are solved by a finite element method to predict the growth rate of the tumor mass as a function of the initial tumor-to-healthy cell density ratio, nutrient concentration, mechanical strain, cell adhesion and geometry. Results are shown for three cases of practical biological interest such as multicellular tumor spheroids (MTSs) and tumor cords. First, the model is validated by experimental data for time-dependent growth of an MTS in a culture medium. The tumor growth pattern follows a biphasic behavior: initially, the rapidly growing TCs tend to saturate the volume available without any significant increase in overall tumor size; then, a classical Gompertzian pattern is observed for the MTS radius variation with time. A core with necrotic cells appears for tumor sizes larger than 150 μm, surrounded by a shell of viable TCs whose thickness stays almost constant with time. A formula to estimate the size of the necrotic core is proposed. In the second case, the MTS is confined within a healthy tissue. The growth rate is reduced, as compared to the first case—mostly due to the relative adhesion of the TCs and HCs to the ECM, and the less favorable transport of nutrients. In particular, for HCs adhering less avidly to the ECM, the healthy tissue is progressively displaced as the malignant mass grows, whereas TC infiltration is predicted for the opposite condition. Interestingly, the infiltration potential of the tumor mass is mostly driven by the relative cell adhesion to the ECM. In the third case, a tumor cord model is analyzed where the malignant cells grow around microvessels in a three-dimensional geometry. It is shown that TCs tend to migrate among adjacent vessels seeking new oxygen and nutrients. This model can predict and optimize the efficacy of anticancer therapeutic strategies. It can be further developed to answer questions on tumor biophysics, related to the effects of ECM stiffness and cell adhesion on TC proliferation.

Population Dynamics of Dactylella oviparasitica and Heterodera schachtii: Toward a Decision Model for Sugar Beet Planting

PubMed Central

Yang, Jiue-in; Benecke, Scott; Jeske, Daniel R.; Rocha, Fernando S.; Smith Becker, Jennifer; Timper, Patricia; Ole Becker, J.

2012-01-01

A series of experiments were performed to examine the population dynamics of the sugarbeet cyst nematode, Heterodera schachtii, and the nematophagus fungus Dactylella oviparasitica. After two nematode generations, the population densities of H. schachtii were measured in relation to various initial infestation densities of both D. oviparasitica and H. schachtii. In general, higher initial population densities of D. oviparasitica were associated with lower final population densities of H. schachtii. Regression models showed that the initial densities of D. oviparasitica were only significant when predicting the final densities of H. schachtii J2 and eggs as well as fungal egg parasitism, while the initial densities of J2 were significant for all final H. schachtii population density measurements. We also showed that the densities of H. schachtii-associated D. oviparasitica fluctuate greatly, with rRNA gene numbers going from zero in most field-soil-collected cysts to an average of 4.24 x 108 in mature females isolated directly from root surfaces. Finally, phylogenetic analysis of rRNA genes suggested that D. oviparasitica belongs to a clade of nematophagous fungi that includes Arkansas Fungus strain L (ARF-L) and that these fungi are widely distributed. We anticipate that these findings will provide foundational data facilitating the development of more effective decision models for sugar beet planting. PMID:23481664

SEMICONDUCTOR TECHNOLOGY: Influence of nitrogen dose on the charge density of nitrogen-implanted buried oxide in SOI wafers

NASA Astrophysics Data System (ADS)

Zhongshan, Zheng; Zhongli, Liu; Ning, Li; Guohua, Li; Enxia, Zhang

2010-02-01

To harden silicon-on-insulator (SOI) wafers fabricated using separation by implanted oxygen (SIMOX) to total-dose irradiation, the technique of nitrogen implantation into the buried oxide (BOX) layer of SIMOX wafers can be used. However, in this work, it has been found that all the nitrogen-implanted BOX layers reveal greater initial positive charge densities, which increased with increasing nitrogen implantation dose. Also, the results indicate that excessively large nitrogen implantation dose reduced the radiation tolerance of BOX for its high initial positive charge density. The bigger initial positive charge densities can be ascribed to the accumulation of implanted nitrogen near the Si-BOX interface after annealing. On the other hand, in our work, it has also been observed that, unlike nitrogen-implanted BOX, all the fluorine-implanted BOX layers show a negative charge density. To obtain the initial charge densities of the BOX layers, the tested samples were fabricated with a metal-BOX-silicon (MBS) structure based on SIMOX wafers for high-frequency capacitance-voltage (C-V) analysis.

Simulation Study on Jet Formability and Damage Characteristics of a Low-Density Material Liner

PubMed Central

Tang, Wenhui; Ran, Xianwen

2018-01-01

The shaped charge tandem warhead is an effective weapon against the ERA (explosive reactive armor). Whether the pre-warhead can reliably initiate the ERA directly determines the entire performance of the tandem warhead. The existing shaped charge pre-warhead mostly adopts a metal shaped jet, which effectively initiates the ERA, but interferes the main shaped jet. This article, on the other hand, explores the possibility of producing a pre-warhead using a low-density material as the liner. The nonlinear dynamic analysis software Autodyn-2D is used to simulate and compare three kinds of low-density shaped jets, including floatglass, Lucite, and Plexiglas, to the copper shaped jet in the effectiveness of impacting ERA. Based on the integrative criteria (including u-d initiation criterion, explosive reactive degree, explosive pressure, and particle velocity of the panels), it can be determined whether the low-density shaped jet can reliably initiate the sandwich charge. The results show that the three kinds of low-density shaped jets can not only initiate the reaction armor, but are also superior to the existing copper shaped jet in ductility, jet tip velocity, jet tip diameter, and the mass; namely, it is feasible to use the low-density material shaped jet to destroy the ERA. PMID:29300351

Major involvement of Na(+) -dependent multivitamin transporter (SLC5A6/SMVT) in uptake of biotin and pantothenic acid by human brain capillary endothelial cells.

PubMed

Uchida, Yasuo; Ito, Katsuaki; Ohtsuki, Sumio; Kubo, Yoshiyuki; Suzuki, Takashi; Terasaki, Tetsuya

2015-07-01

The purpose of this study was to clarify the expression of Na(+) -dependent multivitamin transporter (SLC5A6/SMVT) and its contribution to the supply of biotin and pantothenic acid to the human brain via the blood-brain barrier. DNA microarray and immunohistochemical analyses confirmed that SLC5A6 is expressed in microvessels of human brain. The absolute expression levels of SLC5A6 protein in isolated human and monkey brain microvessels were 1.19 and 0.597 fmol/μg protein, respectively, as determined by a quantitative targeted absolute proteomics technique. Using an antibody-free method established by Kubo et al. (2015), we found that SLC5A6 was preferentially localized at the luminal membrane of brain capillary endothelium. Knock-down analysis using SLC5A6 siRNA showed that SLC5A6 accounts for 88.7% and 98.6% of total [(3) H]biotin and [(3) H]pantothenic acid uptakes, respectively, by human cerebral microvascular endothelial cell line hCMEC/D3. SLC5A6-mediated transport in hCMEC/D3 was markedly inhibited not only by biotin and pantothenic acid, but also by prostaglandin E2, lipoic acid, docosahexaenoic acid, indomethacin, ketoprofen, diclofenac, ibuprofen, phenylbutazone, and flurbiprofen. This study is the first to confirm expression of SLC5A6 in human brain microvessels and to provide evidence that SLC5A6 is a major contributor to luminal uptake of biotin and pantothenic acid at the human blood-brain barrier. In humans, it was unclear (not concluded) about what transport system at the blood-brain barrier (BBB) is responsible for the brain uptakes of two vitamins, biotin and pantothenic acid, which are necessary for brain proper function. This study clarified for the first time that the solute carrier 5A6/Na(+) -dependent multivitamin transporter SLC5A6/SMVT is responsible for the supplies of biotin and pantothenic acid into brain across the BBB in humans. DHA, docosahexaenoic acid; NSAID, non-steroidal anti-inflammatory drug; PGE2, prostaglandin E2. © 2015 International Society for Neurochemistry.

Reduction in cardiolipin decreases mitochondrial spare respiratory capacity and increases glucose transport into and across human brain cerebral microvascular endothelial cells.

PubMed

Nguyen, Hieu M; Mejia, Edgard M; Chang, Wenguang; Wang, Ying; Watson, Emily; On, Ngoc; Miller, Donald W; Hatch, Grant M

2016-10-01

Microvessel endothelial cells form part of the blood-brain barrier, a restrictively permeable interface that allows transport of only specific compounds into the brain. Cardiolipin is a mitochondrial phospholipid required for function of the electron transport chain and ATP generation. We examined the role of cardiolipin in maintaining mitochondrial function necessary to support barrier properties of brain microvessel endothelial cells. Knockdown of the terminal enzyme of cardiolipin synthesis, cardiolipin synthase, in hCMEC/D3 cells resulted in decreased cellular cardiolipin levels compared to controls. The reduction in cardiolipin resulted in decreased mitochondrial spare respiratory capacity, increased pyruvate kinase activity, and increased 2-deoxy-[(3) H]glucose uptake and glucose transporter-1 expression and localization to membranes in hCMEC/D3 cells compared to controls. The mechanism for the increase in glucose uptake was an increase in adenosine-5'-monophosphate kinase and protein kinase B activity and decreased glycogen synthase kinase 3 beta activity. Knockdown of cardiolipin synthase did not affect permeability of fluorescent dextran across confluent hCMEC/D3 monolayers grown on Transwell(®) inserts. In contrast, knockdown of cardiolipin synthase resulted in an increase in 2-deoxy-[(3) H]glucose transport across these monolayers compared to controls. The data indicate that in hCMEC/D3 cells, spare respiratory capacity is dependent on cardiolipin. In addition, reduction in cardiolipin in these cells alters their cellular energy status and this results in increased glucose transport into and across hCMEC/D3 monolayers. Microvessel endothelial cells form part of the blood-brain barrier, a restrictively permeable interface that allows transport of only specific compounds into the brain. In human adult brain endothelial cell hCMEC/D3 monolayers cultured on Transwell(®) plates, knockdown of cardiolipin synthase results in decrease in mitochondrial cardiolipin and decreased mitochondrial spare respiratory capacity. The reduced cardiolipin results in an increased activity of adenosine monophosphate kinase (pAMPK) and protein kinase B (pAKT) and decreased activity of glycogen synthase kinase 3 beta (pGSK3β) which results in elevated glucose transporter-1 (GLUT-1) expression and association with membranes. This in turn increases 2-dexoyglucose uptake from the apical medium into the cells with a resultant 2-deoxyglucose movement into the basolateral medium. © 2016 International Society for Neurochemistry.

YangXue QingNao Wan and Silibinin Capsules, the Two Chinese Medicines, Attenuate Cognitive Impairment in Aged LDLR (+/-) Golden Syrian Hamsters Involving Protection of Blood Brain Barrier

PubMed Central

Gu, You-Yu; Huang, Ping; Li, Quan; Liu, Yu-Ying; Liu, George; Wang, Yu-Hui; Yi, Ming; Yan, Li; Wei, Xiao-Hong; Yang, Lei; Hu, Bai-He; Zhao, Xin-Rong; Chang, Xin; Sun, Kai; Pan, Chun-Shui; Cui, Yuan-Chen; Chen, Qing-Fang; Wang, Chuan-She; Fan, Jing-Yu; Ma, Zhi-Zhong; Han, Jing-Yan

2018-01-01

The purpose of the study was to explore the effect and the underlying mechanism of YangXue QingNao Wan (YXQNW) and Silibinin Capsules (SC), the two Chinese medicines, on cognitive impairment in older people with familial hyperlipidaemia. Fourteen month-old female LDLR (+/-) golden Syrian hamsters were used with their wild type as control. YXQNW (0.5 g/kg/day), SC (0.1 g/kg/day), or YXQNW (0.5 g/kg/day) + SC (0.1 g/kg/day) were administrated orally for 30 days. To assess the effects of the two drugs on plasma lipid content and cognitive ability, plasma TC, TG, LDL-C, and HDL-C were measured, and Y maze task was carried out both before and after administration. After administering of the drugs for 30 days, to evaluate the effect of the two drugs on disturbed blood flow caused by hyperlipidemia, the cerebral blood flow (CBF) was measured. To assess blood–brain barrier integrity, albumin leakage in middle cerebral artery (MCA) area was determined. To evaluate the effect of the drugs on impaired microvessels, the number and morphology of microvessels were assessed in hippocampus area. To further evaluate the ultrastructure of microvessels in hippocampus, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were carried out. To assess the profiles of claudin-5 and occludin in hippocampus, we performed immunofluorescence. Finally, to assess the expression of claudin-5, JAM-1, occludin and ZO-1 in hippocampus, western blot was carried out. The results showed that YXQNW, SC, and YXQNW + SC improved cognitive impairment of aged LDLR (+/-) golden Syrian hamsters without lowering plasma TC and LDL-C. YXQNW, SC, and YXQNW + SC attenuated albumin leakage in MCA area and neuronal damage in hippocampus, concomitant with an increase in CBF, a decrease of perivascular edema and an up-regulated expression of claudin-5, occludin and ZO-1. In conclusion, YXQNW, SC, and YXQNW + SC are able to improve cognitive ability in aged LDLR (+/-) golden Syrian hamsters via mechanisms involving maintaining blood–brain barrier integrity. These findings provide evidence suggesting YXQNW or SC as a potential regime to counteract the cognitive impairment caused by familial hypercholesterolemia.

Dominance of layer-specific microvessel dilation in contrast-enhanced high-resolution fMRI: Comparison between hemodynamic spread and vascular architecture with CLARITY.

PubMed

Poplawsky, Alexander John; Fukuda, Mitsuhiro; Kang, Bok-Man; Kim, Jae Hwan; Suh, Minah; Kim, Seong-Gi

2017-08-16

Contrast-enhanced cerebral blood volume-weighted (CBVw) fMRI response peaks are specific to the layer of evoked synaptic activity (Poplawsky et al., 2015), but the spatial resolution limit of CBVw fMRI is unknown. In this study, we measured the laminar spread of the CBVw fMRI evoked response in the external plexiform layer (EPL, 265 ± 65 μm anatomical thickness, mean ± SD, n = 30 locations from 5 rats) of the rat olfactory bulb during electrical stimulation of the lateral olfactory tract and examined its potential vascular source. First, we obtained the evoked CBVw fMRI responses with a 55 × 55 μm 2 in-plane resolution and a 500-μm thickness at 9.4 T, and found that the fMRI signal peaked predominantly in the inner half of EPL (136 ± 54 μm anatomical thickness). The mean full-width at half-maximum of these fMRI peaks was 347 ± 102 μm and the functional spread was approximately 100 or 200 μm when the effects of the laminar thicknesses of EPL or inner EPL were removed, respectively. Second, we visualized the vascular architecture of EPL from a different rat using a Clear Lipid-exchanged Anatomically Rigid Imaging/immunostaining-compatible Tissue hYdrogel (CLARITY)-based tissue preparation method and confocal microscopy. Microvascular segments with an outer diameter of <11 μm accounted for 64.3% of the total vascular volume within EPL and had a mean segment length of 55 ± 40 μm (n = 472). Additionally, vessels that crossed the EPL border had a mean segment length outside of EPL equal to 73 ± 61 μm (n = 28), which is comparable to half of the functional spread (50-100 μm). Therefore, we conclude that dilation of these microvessels, including capillaries, likely dominate the CBVw fMRI response and that the biological limit of the fMRI spatial resolution is approximately the average length of 1-2 microvessel segments, which may be sufficient for examining sublaminar circuits. Copyright © 2017 Elsevier Inc. All rights reserved.

Acoustic response of compliable microvessels containing ultrasound contrast agents

NASA Astrophysics Data System (ADS)

Qin, Shengping; Ferrara, Katherine W.

2006-10-01

The existing models of the dynamics of ultrasound contrast agents (UCAs) have largely been focused on an UCA surrounded by an infinite liquid. Preliminary investigations of a microbubble's oscillation in a rigid tube have been performed using linear perturbation, under the assumption that the tube diameter is significantly larger than the UCA diameter. In the potential application of drug and gene delivery, it may be desirable to fragment the agent shell within small blood vessels and in some cases to rupture the vessel wall, releasing drugs and genes at the site. The effect of a compliant small blood vessel on the UCA's oscillation and the microvessel's acoustic response are unknown. The aim of this work is to propose a lumped-parameter model to study the interaction of a microbubble oscillation and compliable microvessels. Numerical results demonstrate that in the presence of UCAs, the transmural pressure through the blood vessel substantially increases and thus the vascular permeability is predicted to be enhanced. For a microbubble within an 8 to 40 µm vessel with a peak negative pressure of 0.1 MPa and a centre frequency of 1 MHz, small changes in the microbubble oscillation frequency and maximum diameter are observed. When the ultrasound pressure increases, strong nonlinear oscillation occurs, with an increased circumferential stress on the vessel. For a compliable vessel with a diameter equal to or greater than 8 µm, 0.2 MPa PNP at 1 MHz is predicted to be sufficient for microbubble fragmentation regardless of the vessel diameter; however, for a rigid vessel 0.5 MPa PNP at 1 MHz may not be sufficient to fragment the bubbles. For a centre frequency of 1 MHz, a peak negative pressure of 0.5 MPa is predicted to be sufficient to exceed the stress threshold for vascular rupture in a small (diameter less than 15 µm) compliant vessel. As the vessel or surrounding tissue becomes more rigid, the UCA oscillation and vessel dilation decrease; however the circumferential stress is predicted to increase. Decreasing the vessel size or the centre frequency increases the circumferential stress. For the two frequencies considered in this work, the circumferential stress does not scale as the inverse of the square root of the acoustic frequency va as in the mechanical index, but rather has a stronger frequency dependence, 1/va.

Effect of diadenosine tetraphosphate (AP4A) on coronary arterial microvessels in the beating canine heart.

PubMed

Sugimura, A; Kanatsuka, H; Tanikawa, T; Ong, B H; Shirato, K

2000-11-01

Diadenosine tetraphosphate (AP4A) can be released from activated platelets and the present study examined its effect on coronary arterial microvessels. The role of purinoceptors in the coronary microcirculation in vivo was also investigated. In open chest dogs, coronary arterioles were observed using a microscope with a floating objective. In Protocol 1, AP4A (1, 10, 100 and 1,000 micromol/L) was superfused onto the heart surface before and during the superfusion of 10 micromol/L of 8-phenyltheophylline (8-PT), a P1 purinoceptor blocker. In Protocol 2, AP4A (0.1, 1, 10, and 100 nmol x kg(-1) x min(-1)) was infused into the left anterior descending coronary artery before and during the superfusion of 10 micromol/L of 8-PT. In addition to 8-PT, 30 micromol/L of pyridoxalphosphate-6-azophenyl 2',4'-disulphonic acid (PPADS), a P2X purinoceptor blocker in Protocol 3, or 300 micromol/L of N(omega)-nitro-L-arginine (LNNA) in Protocol 4, was continuously superfused, and 4 doses of AP4A were cumulatively superfused as in Protocol 1. In Protocol 5, 10 micromol/L of alpha,beta-methylene ATP, an agonist of P2X purinoceptors, was superfused for 60 min. Superfused AP4A dilated arterioles in a dose-dependent manner. The magnitude of dilatation was greater in smaller arterioles (small vessel < or = 150 microm: 24.5+/-2.2% vs large vessel > 150 microm: 10.6+/-1.5% at a dose of 1,000 micromol/L, p<0.001). On the other hand, intraluminally applied AP4A also dilated arterioles, but no size dependency was shown. In the presence of 8-PT, vasodilatory responses to superfused and intraluminally applied AP4A were attenuated and the lower doses of AP4A constricted arterioles. This vasoconstrictor effect was not affected by PPADS. The vasodilatory effect of the higher doses of AP4A was almost abolished in the presence of LNNA. Alpha,beta-methylene ATP had no effect on coronary microvascular diameters. AP4A has bidirectional effects on coronary arterial microvessels: vasodilatory effects mediated by P1 purinoceptors and NO, which might be mediated by P2Y purinoceptors, and a vasoconstrictor effect, which is not mediated by P2X purinoceptors.

Role of Proinflammatory Cytokines in Thermal Activation of Lymphocyte Recruitment in Breast Tumor Microvessels

DTIC Science & Technology

2005-03-01

bacterial peritonitis (8), chicken pox (9), and rhinovirus infection (10). In contrast, some studies have shown harmful effects of fever in animal models...March 1 - 6, 2005, Taos, New Mexico . 5. Chen, Q., Passanese, J., Fisher, D., Kucinska, S., Clancy, K., Wang, W.-C., Appenheimer, M., Zhou, L., Repasky...Travel award to attend Keystone Symposium, Leukocyte Trafficking: Cellular and Molecular Mechanisms, March 1 - 6, 2005, Taos, New Mexico . 2. Travel

Experimental study of reparative regeneration processes in the wound treated with bioactive dressings.

PubMed

Chekmareva, I A

2002-02-01

Quantitative and structural functional analysis of granulation tissue cells during treatment with protein-polysaccharide dressing Collahit F was carried out. The preparation effectively cleansed the wound from detritus, prevented secondary infection due to stimulation of the functional activity of macrophages and due to the effect of its antiseptic component (furagin), and stimulated proliferative activity of fibroblasts and granulation tissue microvessels on day 5 of treatment, thus promoting repair processes in the wound.

Intrinsic Cholinergic Mechanisms Regulating Cerebral Blood Flow as a Target for Organophosphate Action

DTIC Science & Technology

1988-10-01

acetyltransferase (ChAT), the ACh- C= synthesizing enzyme. ChAT-immunoreactive cell bodies and processes were localized to autonomic or limbic nuclei throughout...the neuraxis and close appositions with brainstemn microvessels and ependymal cells . Moreover, theA DO , U03 Eoirlo oil ov wavs I 69LET9 SCCUmTYV...spinal preganglionic neurons of the intermediolateral cell columns ([ML). ChAT-immunoreactive cell bodies and processes were localized to autonomic or

Imaging study on acupuncture points

NASA Astrophysics Data System (ADS)

Yan, X. H.; Zhang, X. Y.; Liu, C. L.; Dang, R. S.; Ando, M.; Sugiyama, H.; Chen, H. S.; Ding, G. H.

2009-09-01

The topographic structures of acupuncture points were investigated by using the synchrotron radiation based Dark Field Image (DFI) method. Four following acupuncture points were studied: Sanyinjiao, Neiguan, Zusanli and Tianshu. We have found that at acupuncture point regions there exists the accumulation of micro-vessels. The images taken in the surrounding tissue out of the acupuncture points do not show such kind of structure. It is the first time to reveal directly the specific structure of acupuncture points by X-ray imaging.

Tight junction protein expression and barrier properties of immortalized mouse brain microvessel endothelial cells.

PubMed

Brown, Rachel C; Morris, Andrew P; O'Neil, Roger G

2007-01-26

Understanding the molecular and biochemical mechanisms regulating the blood-brain barrier is aided by in vitro model systems. Many studies have used primary cultures of brain microvessel endothelial cells for this purpose. However, primary cultures limit the generation of material for molecular and biochemical assays since cells grow slowly, are prone to contamination by other neurovascular unit cells, and lose blood-brain barrier characteristics when passaged. To address these issues, immortalized cell lines have been generated. In these studies, we assessed the suitability of the immortalized mouse brain endothelial cell line, bEnd3, as a blood-brain barrier model. RT-PCR and immunofluorescence indicated expression of multiple tight junction proteins. bEnd3 cells formed barriers to radiolabeled sucrose, and responded like primary cultures to disrupting stimuli. Exposing cells to serum-free media on their basolateral side significantly decreased paracellular permeability; astrocyte-conditioned media did not enhance barrier properties. The serum-free media-induced decrease in permeability was correlated with an increase in claudin-5 and zonula occludens-1 immunofluorescence at cell-cell contracts. We conclude that bEnd3 cells are an attractive candidate as a model of the blood-brain barrier due to their rapid growth, maintenance of blood-brain barrier characteristics over repeated passages, formation of functional barriers and amenability to numerous molecular interventions.

TIGHT JUNCTION PROTEIN EXPRESSION AND BARRIER PROPERTIES OF IMMORTALIZED MOUSE BRAIN MICROVESSEL ENDOTHELIAL CELLS

PubMed Central

Brown, Rachel C.; Morris, Andrew P.; O’Neil, Roger G.

2007-01-01

Understanding the molecular and biochemical mechanisms regulating the blood-brain barrier is aided by in vitro model systems. Many studies have used primary cultures of brain microvessel endothelial cells for this purpose. However, primary cultures limit the generation of material for molecular and biochemical assays since cells grow slowly, are prone to contamination by other neurovascular unit cells, and lose blood-brain barrier characteristics when passaged. To address these issues, immortalized cell lines have been generated. In these studies, we assessed the suitability of the immortalized mouse brain endothelial cell line, bEnd3, as a blood-brain barrier model. RT-PCR and immunofluorescence indicated expression of multiple tight junction proteins. bEnd3 cells formed barriers to radiolabeled sucrose, and responded like primary cultures to disrupting stimuli. Exposing cells to serum-free media on their basolateral side significantly decreased paracellular permeability; astrocyte-conditioned media did not enhance barrier properties. The serum-free media-induced decrease in permeability was correlated with an increase in claudin-5 and zonula occludens-1 immunofluorescence at cell-cell contracts. We conclude that bEnd3 cells are an attractive candidate as a model of the blood-brain barrier due to their rapid growth, maintenance of blood-brain barrier characteristics over repeated passages, formation of functional barriers and amenability to numerous molecular interventions. PMID:17169347

Abluminal Stimulation of Sphingosine 1-Phosphate Receptors 1 and 3 Promotes and Stabilizes Endothelial Sprout Formation

PubMed Central

Lenz, Steven M.; Awojoodu, Anthony O.

2015-01-01

Local delivery of lipid mediators has become a promising new approach for therapeutic angiogenesis and regenerative medicine. In this study, we investigated how gradient stimulation (either abluminal/distal or luminal/proximal) of engineered microvessels with sphingosine 1-phosphate (S1P) receptor-subtype-targeted molecules affects endothelial sprout growth using a microfluidic device. Our studies show that distal stimulation of microvessels with FTY720, an S1P1/3 selective agonist, promotes both arterial and venular sprout growth, whereas proximal stimulation does not. Using novel pharmacological antagonists of S1P receptor subtypes, we further show that S1P3 functionality is necessary for VEGF-induced sprouting, and confirmed these findings ex vivo using a murine aortic ring assay from S1P3-deficient mice. S1P3 agonist stimulation enhanced vascular stability in both cell types via upregulation of the interendothelial junction protein VE-cadherin. Lastly, S1P3 activation under flow promoted endothelial sprouting and branching while decreasing migratory cell fate in the microfluidic device. We used an in vivo murine dorsal skinfold window chamber model to confirm S1P3's role in neovascular branching. Together, these data suggest that a distal transendothelial gradient of S1P1/3-targeted drugs is an effective technique for both enhancing and stabilizing capillary morphogenesis in angiogenic applications. PMID:25315888

ATP: a vasoactive signal in the pericyte-containing microvasculature of the rat retina

PubMed Central

Kawamura, Hajime; Sugiyama, Tetsuya; Wu, David M; Kobayashi, Masato; Yamanishi, Shigeki; Katsumura, Kozo; Puro, Donald G

2003-01-01

In this study we tested the hypothesis that extracellular ATP regulates the function of the pericyte-containing retinal microvessels. Pericytes, which are more numerous in the retina than in any other tissue, are abluminally located cells that may adjust capillary perfusion by contracting and relaxing. At present, knowledge of the vasoactive molecules that regulate pericyte function is limited. Here, we focused on the actions of extracellular ATP because this nucleotide is a putative glial-to-vascular signal, as well as being a substance released by activated platelets and injured cells. In microvessels freshly isolated from the adult rat retina, we monitored ionic currents via perforated-patch pipettes, measured intracellular calcium levels with the use of fura-2, and visualized microvascular contractions with the aid of time-lapse photography. We found that ATP induced depolarizing changes in the ionic currents, increased calcium levels and caused pericytes to contract. P2X7 receptors and UTP-activated receptors mediated these effects. Consistent with ATP serving as a vasoconstrictor for the pericyte-containing microvasculature of the retina, the microvascular lumen narrowed when an adjacent pericyte contracted. In addition, the sustained activation of P2X7 receptors inhibited cell-to-cell electrotonic transmission within the microvascular networks. Thus, ATP not only affects the contractility of individual pericytes, but also appears to regulate the spatial and temporal dynamics of the vasomotor response. PMID:12876212

Objective evaluation of visibility in virtual chromoendoscopy for esophageal squamous carcinoma using a color difference formula

NASA Astrophysics Data System (ADS)

Inoue, Masahito; Miyake, Yoichi; Odaka, Takeo; Sato, Toru; Watanabe, Yoshiyuki; Sakama, Atsunori; Zenbutsu, Satoki; Yokosuka, Osamu

2010-09-01

Computed virtual chromoendoscopy with flexible spectral imaging color enhancement (FICE) is a new dyeless imaging technique that enhances mucosal and vascular patterns. However, a method for selecting a suitable wavelength for a particular condition has not been established. The aim of this study is to evaluate the color difference method for quality assessment of FICE images of the intrapapillary capillary loop in magnifying endoscopy for esophageal squamous cell carcinoma. The color difference between 60 microvessels and background mucosa observed using the magnifying endoscope was 8.31+/-2.84 SD under white light and 12.26+/-3.14 (p=0.0031), 11.70+/-4.49 (p=0.0106), and 17.49+/-5.40 (p<0.0001) in FICE modes A, B, and C, respectively. The visibility scores for microvessels observed by medical students were 6.00+/-1.12 points under white light and 11.1+/-2.25 (p<0.0001), 8.65+/-2.06 (p=0.0001), and 12.55+/-2.56 (p<0.0001) in FICE modes A, B, and C, respectively. Furthermore, the measurement of color difference was correlated with the visibility score assigned by medical students (Pearson's correlation coefficient=0.583, p<0.0001) In conclusion, the color difference method corresponds to human vision and is an appropriate method for evaluation of endoscopic images.

Modified C-reactive protein is expressed by stroke neovessels and is a potent activator of angiogenesis in vitro.

PubMed

Slevin, Mark; Matou-Nasri, Sabine; Turu, Marta; Luque, Ana; Rovira, Norma; Badimon, Lina; Boluda, Susana; Potempa, Lawrence; Sanfeliu, Coral; de Vera, Nuria; Krupinski, Jerzy

2010-01-01

Native C-reactive protein (nCRP) is a pentameric oligo-protein and an acute phase reactant whose serum expression is increased in patients with inflammatory disease. We have identified by immunohistochemistry, significant expression of a tissue-binding insoluble modified version or monomeric form of CRP (mCRP) associated with angiogenic microvessels in peri-infarcted regions of patients studied with acute ischaemic stroke. mCRP, but not nCRP was expressed in the cytoplasm and nucleus of damaged neurons. mCRP co-localized with CD105, a marker of angiogenesis in regions of revascularisation. In vitro investigations demonstrated that mCRP was preferentially expressed in human brain microvessel endothelial cells following oxygen-glucose deprivation and mCRP (but not column purified nCRP) associated with the endothelial cell surface, and was angiogenic to vascular endothelial cells, stimulating migration and tube formation in matrigel more strongly than fibroblast growth factor-2. The mechanism of signal transduction was not through the CD16 receptor. Western blotting showed that mCRP stimulated phosphorylation of the key down-stream mitogenic signalling protein ERK1/2. Pharmacological inhibition of ERK1/2 phosphorylation blocked the angiogenic effects of mCRP. We propose that mCRP may contribute to the neovascularization process and because of its abundant presence, be important in modulating angiogenesis in both acute stroke and later during neuro-recovery.

Two-photon microscopy allows imaging and characterization of cochlear microvasculature in vivo.

PubMed

Ihler, Friedrich; Bertlich, Mattis; Weiss, Bernhard; Dietzel, Steffen; Canis, Martin

2015-01-01

Impairment of cochlear blood flow has been discussed as factor in the pathophysiology of various inner ear disorders. However, the microscopic study of cochlear microcirculation is limited due to small scale and anatomical constraints. Here, two-photon fluorescence microscopy is applied to visualize cochlear microvessels. Guinea pigs were injected with Fluorescein isothiocyanate- or Texas red-dextrane as plasma marker. Intravital microscopy was performed in four animals and explanted cochleae from four animals were studied. The vascular architecture of the cochlea was visualized up to a depth of 90.0±22.7 μm. Imaging yielded a mean contrast-to-noise ratio (CNR) of 3.3±1.7. Mean diameter in vivo was 16.5±6.0 μm for arterioles and 8.0±2.4 μm for capillaries. In explanted cochleae, the diameter of radiating arterioles and capillaries was measured with 12.2±1.6 μm and 6.6±1.0 μm, respectively. The difference between capillaries and arterioles was statistically significant in both experimental setups (P<0.001 and P=0.022, two-way ANOVA). Measured vessel diameters in vivo and ex vivo were in agreement with published data. We conclude that two-photon fluorescence microscopy allows the investigation of cochlear microvessels and is potentially a valuable tool for inner ear research.

Fibroblast Growth Factor 9 Imparts Hierarchy and Vasoreactivity to the Microcirculation of Renal Tumors and Suppresses Metastases*

PubMed Central

Yin, Hao; Frontini, Matthew J.; Arpino, John-Michael; Nong, Zengxuan; O'Neil, Caroline; Xu, Yiwen; Balint, Brittany; Ward, Aaron D.; Chakrabarti, Subrata; Ellis, Christopher G.; Gros, Robert; Pickering, J. Geoffrey

2015-01-01

Tumor vessel normalization has been proposed as a therapeutic paradigm. However, normal microvessels are hierarchical and vasoreactive with single file transit of red blood cells through capillaries. Such a network has not been identified in malignant tumors. We tested whether the chaotic tumor microcirculation could be reconfigured by the mesenchyme-selective growth factor, FGF9. Delivery of FGF9 to renal tumors in mice yielded microvessels that were covered by pericytes, smooth muscle cells, and a collagen-fortified basement membrane. This was associated with reduced pulmonary metastases. Intravital microvascular imaging revealed a haphazard web of channels in control tumors but a network of arterioles, bona fide capillaries, and venules in FGF9-expressing tumors. Moreover, whereas vasoreactivity was absent in control tumors, arterioles in FGF9-expressing tumors could constrict and dilate in response to adrenergic and nitric oxide releasing agents, respectively. These changes were accompanied by reduced hypoxia in the tumor core and reduced expression of the angiogenic factor VEGF-A. FGF9 was found to selectively amplify a population of PDGFRβ-positive stromal cells in the tumor and blocking PDGFRβ prevented microvascular differentiation by FGF9 and also worsened metastases. We conclude that harnessing local mesenchymal stromal cells with FGF9 can differentiate the tumor microvasculature to an extent not observed previously. PMID:26183774

Vascular signaling abnormalities in Alzheimer disease.

PubMed

Grammas, Paula; Sanchez, Alma; Tripathy, Debjani; Luo, Ester; Martinez, Joseph

2011-08-01

Our laboratory has documented that brain microvessels derived from patients with Alzheimer disease (AD) express or release a myriad of factors that have been implicated in vascular activation and angiogenesis. In addition, we have documented that signaling cascades associated with vascular activation and angiogenesis are upregulated in AD-derived brain microvessels. These results are consistent with emerging data suggesting that factors and processes characteristic of vascular activation and angiogenesis are found in the AD brain. Despite increases in proangiogenic factors and signals in the AD brain, however, evidence for increased vascularity in AD is lacking. Cerebral hypoperfusion/hypoxia, a potent stimulus for vascular activation and angiogenesis, triggers hypometabolic, cognitive, and degenerative changes in the brain. In our working model, hypoxia stimulates the angiogenic process; yet, there is no new vessel growth. Therefore, there are no feedback signals to shut off vascular activation, and endothelial cells become irreversibly activated. This activation results in release of a large number of proteases, inflammatory proteins, and other gene products with biologic activity that can injure or kill neurons. Pathologic activation of brain vasculature may contribute noxious mediators that lead to neuronal injury and disease processes in AD brains. This concept is supported by preliminary experiments in our laboratory, which show that pharmacologic blockade of vascular activation improves cognitive function in an animal model of AD. Thus, "vascular activation" could be a novel, unexplored therapeutic target in AD.

Laparoscopic ischemic conditioning of the stomach increases neovascularization of the gastric conduit in patients undergoing esophagectomy for cancer.

PubMed

Pham, Thai H; Melton, Shelby D; McLaren, Patrick J; Mokdad, Ali A; Huerta, Sergio; Wang, David H; Perry, Kyle A; Hardaker, Hope L; Dolan, James P

2017-09-01

Gastric ischemic preconditioning has been proposed to improve blood flow and reduce the incidence of anastomotic complications following esophagectomy with gastric pull-up. This study aimed to evaluate the effect of prolonged ischemic preconditioning on the degree of neovascularization in the distal gastric conduit at the time of esophagectomy. A retrospective review of a prospectively maintained database identified 30 patients who underwent esophagectomy. The patients were divided into three groups: control (no preconditioning, n = 9), partial (short gastric vessel ligation only, n = 8), and complete ischemic preconditioning (left and short gastric vessel ligation, n = 13). Microvessel counts were assessed, using immunohistologic analysis to determine the degree of neovascularization at the distal gastric margin. The groups did not differ in age, gender, BMI, pathologic stage, or cancer subtype. Ischemic preconditioning durations were 163 ± 156 days for partial ischemic preconditioning, compared to 95 ± 50 days for complete ischemic preconditioning (P = 0.2). Immunohistologic analysis demonstrated an increase in microvessel counts of 29% following partial ischemic preconditioning (P = 0.3) and 67% after complete ischemic preconditioning (P < 0.0001), compared to controls. Our study indicates that prolonged ischemic preconditioning is safe and does not interfere with subsequent esophagectomy. Complete ischemic preconditioning increased neovascularization in the distal gastric conduit. © 2017 Wiley Periodicals, Inc.

Reconstructing the Initial Density Field of the Local Universe: Methods and Tests with Mock Catalogs

NASA Astrophysics Data System (ADS)

Wang, Huiyuan; Mo, H. J.; Yang, Xiaohu; van den Bosch, Frank C.

2013-07-01

Our research objective in this paper is to reconstruct an initial linear density field, which follows the multivariate Gaussian distribution with variances given by the linear power spectrum of the current cold dark matter model and evolves through gravitational instabilities to the present-day density field in the local universe. For this purpose, we develop a Hamiltonian Markov Chain Monte Carlo method to obtain the linear density field from a posterior probability function that consists of two components: a prior of a Gaussian density field with a given linear spectrum and a likelihood term that is given by the current density field. The present-day density field can be reconstructed from galaxy groups using the method developed in Wang et al. Using a realistic mock Sloan Digital Sky Survey DR7, obtained by populating dark matter halos in the Millennium simulation (MS) with galaxies, we show that our method can effectively and accurately recover both the amplitudes and phases of the initial, linear density field. To examine the accuracy of our method, we use N-body simulations to evolve these reconstructed initial conditions to the present day. The resimulated density field thus obtained accurately matches the original density field of the MS in the density range 0.3 \\lesssim \\rho /\\bar{\\rho } \\lesssim 20 without any significant bias. In particular, the Fourier phases of the resimulated density fields are tightly correlated with those of the original simulation down to a scale corresponding to a wavenumber of ~1 h Mpc-1, much smaller than the translinear scale, which corresponds to a wavenumber of ~0.15 h Mpc-1.

Ignitor with stable low-energy thermite igniting system

DOEpatents

Kelly, Michael D.; Munger, Alan C.

1991-02-05

A stable compact low-energy igniting system in an ignitor utilizes two components, an initiating charge and an output charge. The initiating charge is a thermite in ultra-fine powder form compacted to 50-70% of theoretical maximum density and disposed in a cavity of a header of the ignitor adjacent to an electrical ignition device, or bridgewire, mounted in the header cavity. The initiating charge is ignitable by operation of the ignition device in a hot-wire mode. The output charge is a thermite in high-density consoladated form compacted to 90-99% of theoretical maximum density and disposed adjacent to the initiating charge on an opposite end thereof from the electrical ignition device and ignitable by the initiating charge. A sleeve is provided for mounting the output charge to the ignitor header with the initiating charge confined therebetween in the cavity.

Adhesion and splash dispersal of Salmonella enterica Typhimurium on tomato leaflets: effects of rdar morphotype and trichome density.

PubMed

Cevallos-Cevallos, Juan M; Gu, Ganyu; Danyluk, Michelle D; van Bruggen, Ariena H C

2012-11-01

Salmonella enterica strains with rdar (red dry and rough) and saw (smooth and white) morphotypes have previously been associated with tomato outbreaks but the dispersal mechanisms of these morphotypes are still poorly understood. In this study, Salmonella adhesion was distinguished from attachment by comparing different contact periods. Initial adhesion of rdar and saw morphotypes of Salmonella was compared in relation to tomato plants with different leaf trichome densities. Trichome densities were increased or reduced by treatment with jasmonic or salicylic acid, respectively. The overall effect of Salmonella morphotype and trichome density on splash dispersal was assessed in a rain simulator and correlated to cell hydrophobicity and initial adhesion. The presence of the rdar morphotype increased initial adhesion at high trichome densities but not at low trichome densities. Attachment of the rdar strain occurred after 30s contact time regardless of trichome density. Splash dispersal was slightly further for the saw morphotype than the rdar morphotype of S. enterica at all trichome densities. Salmonella cells of both morphotypes survived significantly better on the surface of high trichome density leaflets. Copyright © 2012 Elsevier B.V. All rights reserved.

Temperature-dependent elimination efficiency on Phaeocystis globosa by different initial population sizes of rotifer Brachionus plicatilis.

PubMed

Sun, Yunfei; Wang, Yuanyuan; Lei, Jin; Qian, Chenchen; Zhu, Xuexia; Akbar, Siddiq; Huang, Yuan; Yang, Zhou

2018-07-01

Due to sea water eutrophication and global warming, the harmful Phaeocystis blooms outbreak frequently in coastal waters, which cause a serious threat to marine ecosystem. The application of rotifer to control the harmful alga is a promising way. To investigate the influence of initial rotifer density and temperature on the ability of rotifer Brachionus plicatilis to eliminate Phaeocystis globosa population, we cultured P. globosa with different initial rotifer densities (1, 3, 5 inds mL -1 ) at 19, 22, 25, 28, and 31 °C for 9-16 d. Results showed that the population of rotifer feeding on Phaeocystis increased rapidly and higher temperatures favored the growth of P. globosa and B. plicatilis. With increased initial rotifer density and temperature, both the clearance rate of rotifer and the reduction rate of P. globosa increased, and thus P. globosa were eliminated earlier. Both temperature and initial rotifer density had significant effects on clearance rate of rotifer and the time to Phaeocystis extinction, and there was a significant interaction between the two factors on the two parameters, i.e., the effect of initial rotifer density on eliminating Phaeocystis decreased with increasing temperature. The rotifer in 5 inds mL -1 at 28 °C eliminated P. globosa in 4 d, whereas the rotifer in 1 ind mL -1 at 19 °C spent about 16 d on eliminating P. globosa. In conclusion, higher temperature and bigger initial rotifer density promote rotifer to eliminate the harmful P. globosa, and the optimal temperature for rotifer to clear P. globosa is 28 °C. Copyright © 2018 Elsevier Ltd. All rights reserved.

Grading vascularity from histopathological images based on traveling salesman distance and vessel size

NASA Astrophysics Data System (ADS)

Niazi, M. Khalid Khan; Hemminger, Jessica; Kurt, Habibe; Lozanski, Gerard; Gurcan, Metin

2014-03-01

Vascularity represents an important element of tissue/tumor microenvironment and is implicated in tumor growth, metastatic potential and resistence to therapy. Small blood vessels can be visualized using immunohistochemical stains specific to vascular cells. However, currently used manual methods to assess vascular density are poorly reproducible and are at best semi quantitative. Computer based quantitative and objective methods to measure microvessel density are urgently needed to better understand and clinically utilize microvascular density information. We propose a new method to quantify vascularity from images of bone marrow biopsies stained for CD34 vascular lining cells protein as a model. The method starts by automatically segmenting the blood vessels by methods of maxlink thresholding and minimum graph cuts. The segmentation is followed by morphological post-processing to reduce blast and small spurious objects from the bone marrow images. To classify the images into one of the four grades, we extracted 20 features from the segmented blood vessel images. These features include first four moments of the distribution of the area of blood vessels, first four moments of the distribution of 1) the edge weights in the minimum spanning tree of the blood vessels, 2) the shortest distance between blood vessels, 3) the homogeneity of the shortest distance (absolute difference in distance between consecutive blood vessels along the shortest path) between blood vessels and 5) blood vessel orientation. The method was tested on 26 bone marrow biopsy images stained with CD34 IHC stain, which were evaluated by three pathologists. The pathologists took part in this study by quantifying blood vessel density using gestalt assessment in hematopoietic bone marrow portions of bone marrow core biopsies images. To determine the intra-reader variability, each image was graded twice by each pathologist with two-week interval in between their readings. For each image, the ground truth (grade) was acquired through consensus among the three pathologists at the end of the study. A ranking of the features reveals that the fourth moment of the distribution of the area of blood vessels along with the first moment of the distribution of the shortest distance between blood vessels can correctly grade 68.2% of the bone marrow biopsies, while the intra- and inter-reader variability among the pathologists are 66.9% and 40.0%, respectively.

The Initial Physical Conditions of Kepler-36 b and c

NASA Astrophysics Data System (ADS)

Owen, James E.; Morton, Timothy. D.

2016-03-01

The Kepler-36 planetary system consists of two exoplanets at similar separations (0.115 and 0.128 au), which have dramatically different densities. The inner planet has a density consistent with an Earth-like composition, while the outer planet is extremely low density, such that it must contain a voluminous H/He envelope. Such a density difference would pose a problem for any formation mechanism if their current densities were representative of their composition at formation. However, both planets are at close enough separations to have undergone significant evaporation in the past. We constrain the core mass, core composition, initial envelope mass, and initial cooling time of each planet using evaporation models conditioned on their present-day masses and radii, as inferred from Kepler photometry and transit timing analysis. The inner planet is consistent with being an evaporatively stripped core, while the outer planet has retained some of its initial envelope due to its higher core mass. Therefore, both planets could have had a similar formation pathway, with the inner planet having an initial envelope-mass fraction of ≲10% and core mass of ˜4.4 M⊕, while the outer had an initial envelope-mass fraction of the order of 15%-30% and core mass ˜7.3 M⊕. Finally, our results indicate that the outer planet had a long (≳30 Myr) initial cooling time, much longer than would naively be predicted from simple timescale arguments. The long initial cooling time could be evidence for a dramatic early cooling episode such as the recently proposed “boil-off” process.

The Correlation Between Green Density and the Occurrence of Honeycomb in Kiln-Dried

Treesearch

Robert A. Harris; Philip A. Araman

1995-01-01

Fresh-cut, 5/4 red oak (Quercus sp.) boards were weighed, measured to determine volume and then kiln-dried to determine if the initial green density (green weight/green volume) was correlated to the occurrence of honeycomb. A positive relationship was found between the occurrence of honeycomb during drying and the initial green density. These results...

Constraints on rapidity-dependent initial conditions from charged-particle pseudorapidity densities and two-particle correlations

NASA Astrophysics Data System (ADS)

Ke, Weiyao; Moreland, J. Scott; Bernhard, Jonah E.; Bass, Steffen A.

2017-10-01

We study the initial three-dimensional spatial configuration of the quark-gluon plasma (QGP) produced in relativistic heavy-ion collisions using centrality and pseudorapidity-dependent measurements of the medium's charged particle density and two-particle correlations. A cumulant-generating function is first used to parametrize the rapidity dependence of local entropy deposition and extend arbitrary boost-invariant initial conditions to nonzero beam rapidities. The model is then compared to p +Pb and Pb + Pb charged-particle pseudorapidity densities and two-particle pseudorapidity correlations and systematically optimized using Bayesian parameter estimation to extract high-probability initial condition parameters. The optimized initial conditions are then compared to a number of experimental observables including the pseudorapidity-dependent anisotropic flows, event-plane decorrelations, and flow correlations. We find that the form of the initial local longitudinal entropy profile is well constrained by these experimental measurements.

Reversal of renal dysfunction by targeted administration of VEGF into the stenotic kidney: a novel potential therapeutic approach.

PubMed

Chade, Alejandro R; Kelsen, Silvia

2012-05-15

Renal microvascular (MV) damage and loss contribute to the progression of renal injury in renovascular disease (RVD). Whether a targeted intervention in renal microcirculation could reverse renal damage is unknown. We hypothesized that intrarenal vascular endothelial growth factor (VEGF) therapy will reverse renal dysfunction and decrease renal injury in experimental RVD. Unilateral renal artery stenosis (RAS) was induced in 14 pigs, as a surrogate of chronic RVD. Six weeks later, renal blood flow (RBF) and glomerular filtration rate (GFR) were quantified in vivo in the stenotic kidney using multidetector computed tomography (CT). Then, intrarenal rhVEGF-165 or vehicle was randomly administered into the stenotic kidneys (n = 7/group), they were observed for 4 additional wk, in vivo studies were repeated, and then renal MV density was quantified by 3D micro-CT, and expression of angiogenic factors and fibrosis was determined. RBF and GFR, MV density, and renal expression of VEGF and downstream mediators such as p-ERK 1/2, Akt, and eNOS were significantly reduced after 6 and at 10 wk of untreated RAS compared with normal controls. Remarkably, administration of VEGF at 6 wk normalized RBF (from 393.6 ± 50.3 to 607.0 ± 45.33 ml/min, P < 0.05 vs. RAS) and GFR (from 43.4 ± 3.4 to 66.6 ± 10.3 ml/min, P < 0.05 vs. RAS) at 10 wk, accompanied by increased angiogenic signaling, augmented renal MV density, and attenuated renal scarring. This study shows promising therapeutic effects of a targeted renal intervention, using an established clinically relevant large-animal model of chronic RAS. It also implies that disruption of renal MV integrity and function plays a pivotal role in the progression of renal injury in the stenotic kidney. Furthermore, it shows a high level of plasticity of renal microvessels to a single-dose VEGF-targeted intervention after established renal injury, supporting promising renoprotective effects of a novel potential therapeutic intervention to treat chronic RVD.

Reversal of renal dysfunction by targeted administration of VEGF into the stenotic kidney: a novel potential therapeutic approach

PubMed Central

Kelsen, Silvia

2012-01-01

Renal microvascular (MV) damage and loss contribute to the progression of renal injury in renovascular disease (RVD). Whether a targeted intervention in renal microcirculation could reverse renal damage is unknown. We hypothesized that intrarenal vascular endothelial growth factor (VEGF) therapy will reverse renal dysfunction and decrease renal injury in experimental RVD. Unilateral renal artery stenosis (RAS) was induced in 14 pigs, as a surrogate of chronic RVD. Six weeks later, renal blood flow (RBF) and glomerular filtration rate (GFR) were quantified in vivo in the stenotic kidney using multidetector computed tomography (CT). Then, intrarenal rhVEGF-165 or vehicle was randomly administered into the stenotic kidneys (n = 7/group), they were observed for 4 additional wk, in vivo studies were repeated, and then renal MV density was quantified by 3D micro-CT, and expression of angiogenic factors and fibrosis was determined. RBF and GFR, MV density, and renal expression of VEGF and downstream mediators such as p-ERK 1/2, Akt, and eNOS were significantly reduced after 6 and at 10 wk of untreated RAS compared with normal controls. Remarkably, administration of VEGF at 6 wk normalized RBF (from 393.6 ± 50.3 to 607.0 ± 45.33 ml/min, P < 0.05 vs. RAS) and GFR (from 43.4 ± 3.4 to 66.6 ± 10.3 ml/min, P < 0.05 vs. RAS) at 10 wk, accompanied by increased angiogenic signaling, augmented renal MV density, and attenuated renal scarring. This study shows promising therapeutic effects of a targeted renal intervention, using an established clinically relevant large-animal model of chronic RAS. It also implies that disruption of renal MV integrity and function plays a pivotal role in the progression of renal injury in the stenotic kidney. Furthermore, it shows a high level of plasticity of renal microvessels to a single-dose VEGF-targeted intervention after established renal injury, supporting promising renoprotective effects of a novel potential therapeutic intervention to treat chronic RVD. PMID:22357917

Divergent Effects of Losartan and Metoprolol on Cardiac Remodeling, C‐kit+ Cells, Proliferation and Apoptosis in the Left Ventricle after Myocardial Infarction

PubMed Central

Serpi, Raisa; Tolonen, Anna‐Maria; Tenhunen, Olli; Pieviläinen, Oskari; Kubin, Anna‐Maria; Vaskivuo, Tommi; Soini, Ylermi; Kerkelä, Risto; Leskinen, Hanna; Ruskoaho, Heikki

2009-01-01

Abstract There is strong evidence for the use of angiotensin converting enzyme inhibitors and beta‐blockers to reduce morbidity and mortality in patients with myocardial infarction (MI), whereas the effect of angiotensin receptor blockers is less clear. We evaluated the effects of an angiotensin receptor blocker losartan and a beta‐blocker metoprolol on left ventricular (LV) remodeling, c‐kit+ cells, proliferation, fibrosis, apoptosis, and angiogenesis using a model of coronary ligation in rats. Metoprolol treatment for 2 weeks improved LV systolic function. In contrast, losartan triggered deleterious structural remodeling and functional deterioration of LV systolic function, ejection fraction being 41% and fractional shortening 47% lower in losartan group than in controls 2 weeks after MI. The number of c‐kit+ cells as well as expression of Ki‐67 was increased by metoprolol. Losartan‐induced thinning of the anterior wall and ventricular dilation were associated with increased apoptosis and fibrosis, while losartan had no effect on the expression of c‐kit or Ki‐67. Metoprolol or losartan had no effect on microvessel density. These results demonstrate that beta‐blocker treatment attenuated adverse remodeling via c‐kit+ cells and proliferation, whereas angiotensin receptor blocker‐induced worsening of LV systolic function was associated with increased apoptosis and fibrosis in the peri‐infarct region. PMID:20443934

Metformin suppresses ovarian cancer growth and metastasis with enhancement of cisplatin cytotoxicity in vivo.

PubMed

Rattan, Ramandeep; Graham, Rondell P; Maguire, Jacie L; Giri, Shailendra; Shridhar, Viji

2011-05-01

Ovarian cancer is the most lethal gynecologic cancer in women. Its high mortality rate (68%) reflects the fact that 75% of patients have extensive (>stage III) disease at diagnosis and also the limited efficacy of currently available therapies. Consequently, there is clearly a great need to develop improved upfront and salvage therapies for ovarian cancer. Here, we investigated the efficacy of metformin alone and in combination with cisplatin in vivo. A2780 ovarian cancer cells were injected intraperitoneally in nude mice; A2780-induced tumors in nude mice, when treated with metformin in drinking water, resulted in a significant reduction of tumor growth, accompanied by inhibition of tumor cell proliferation (as assessed by immunohistochemical staining of Ki-67, Cyclin D1) as well as decreased live tumor size and mitotic cell count. Metformin-induced activation of AMPK/mTOR pathway was accompanied by decreased microvessel density and vascular endothelial growth factor expression. More importantly, metformin treatment inhibited the growth of metastatic nodules in the lung and significantly potentiated cisplatin-induced cytotoxicity resulting in approximately 90% reduction in tumor growth compared with treatment by either of the drugs alone. Collectively, our data show for the first time that, in addition to inhibiting tumor cell proliferation, metformin treatment inhibits both angiogenesis and metastatic spread of ovarian cancer. Overall, our study provides a strong rationale for use of metformin in ovarian cancer treatment.

Pentastatin-1, a collagen IV derived 20-mer peptide, suppresses tumor growth in a small cell lung cancer xenograft model.

PubMed

Koskimaki, Jacob E; Karagiannis, Emmanouil D; Tang, Benjamin C; Hammers, Hans; Watkins, D Neil; Pili, Roberto; Popel, Aleksander S

2010-02-01

Angiogenesis is the formation of neovasculature from a pre-existing vascular network. Progression of solid tumors including lung cancer is angiogenesis-dependent. We previously introduced a bioinformatics-based methodology to identify endogenous anti-angiogenic peptide sequences, and validated these predictions in vitro in human umbilical vein endothelial cell (HUVEC) proliferation and migration assays. One family of peptides with high activity is derived from the alpha-fibrils of type IV collagen. Based on the results from the in vitro screening, we have evaluated the ability of a 20 amino acid peptide derived from the alpha5 fibril of type IV collagen, pentastatin-1, to suppress vessel growth in an angioreactor-based directed in vivo angiogenesis assay (DIVAA). In addition, pentastatin-1 suppressed tumor growth with intraperitoneal peptide administration in a small cell lung cancer (SCLC) xenograft model in nude mice using the NCI-H82 human cancer cell line. Pentastatin-1 decreased the invasion of vessels into angioreactors in vivo in a dose dependent manner. The peptide also decreased the rate of tumor growth and microvascular density in vivo in a small cell lung cancer xenograft model. The peptide treatment significantly decreased the invasion of microvessels in angioreactors and the rate of tumor growth in the xenograft model, indicating potential treatment for angiogenesis-dependent disease, and for translational development as a therapeutic agent for lung cancer.

Fisetin and polymeric micelles encapsulating fisetin exhibit potent cytotoxic effects towards ovarian cancer cells.

PubMed

Xiao, Xue; Zou, Juan; Fang, Yin; Meng, Yibo; Xiao, Chao; Fu, Jiaxin; Liu, Shiyu; Bai, Peng; Yao, Yuan

2018-03-15

The anti-tumor activities of Natural compounds and their derivatives are of great interest to pharmaceutical industries. Fisetin is one of prospective natural compounds in this regard but unfortunately with poor hydrophilicity. The effects of unmodified and modified fisetin in cultured ovarian cancer cells were compared by transmission electronmicroscopy to determine apoptotic bodies, MTT assay to quantitate cell numbers, and fluorescence activated cell sorting analyse of various markers to determine the apoptotic state. In addition, the efficacy of fisetin and fisetin-micelles in vivo was determined by using immunocompromised mice. Apoptosis was measured by established markers using both western blot analysis and immunochemistry. Angiogenesis in a xenograft mouse model carring SKOV3 cells was evaluated by color Doppler ultrasound and immunohistochemistry. Multiple lines of evidence indicated that fisetin and fisetin micelles induce apoptosis in ovarian cancer cells in a dose-dependent manner. Histological analysis, terminal deoxynucleotidyltransferase-mediated nick-end labeling assay, western blot, immunohistochemical detection and microvessel density detection demonstrated that fisetin and fisetin micelles induced increased tumor apoptosis, proliferation suppression and antiangiogenesis activities. As far as we know, the present study is the first time to demonstrate the potency of both fisetin and fisetin micelles inducing apoptosis in ovarian cancer cells. Further studies will be needed to validate the therapeutic potential of fisetin and fisetin micelles in ovarian cancer treatment.

Vitamin D binding protein-macrophage activating factor inhibits HCC in SCID mice.

PubMed

Nonaka, Koichi; Onizuka, Shinya; Ishibashi, Hiromi; Uto, Yoshihiro; Hori, Hitoshi; Nakayama, Toshiyuki; Matsuura, Nariaki; Kanematsu, Takashi; Fujioka, Hikaru

2012-01-01

A high incidence of recurrence after treatment is the most serious problem in hepatocellular carcinoma (HCC). Therefore, a new strategy for the treatment of the disease is needed. The aim of the present study was to investigate whether vitamin D binding protein-macrophage activating factor (DBP-maf) is able to inhibit the growth of HCC. The effects of DBP-maf on endothelial cells and macrophage were evaluated by WST-1 assay and phagocytosis assay, respectively. Human HCC cells (HepG2) were implanted into the dorsum of severe combined immunodeficiency (SCID) mice. These mice were divided into control and DBP-maf treatment groups (n = 10/group). The mice in the treatment group received 40 ng/kg/d of DBP-maf for 21 d. DBP-maf showed anti-proliferative activity against endothelial cells and also activated phagocytosis by macrophages. DBP-maf inhibited the growth of HCC cells (treatment group: 126 ± 18mm(3), untreated group: 1691.5 ± 546.9mm(3), P = 0.0077). Histologic examinations of the tumors revealed the microvessel density was reduced and more macrophage infiltration was demonstrated in the tumor of mice in the treatment group. DBP-maf has at least two novel functions, namely, an anti-angiogenic activity and tumor killing activity through the activation of macrophages. DBP-maf may therefore represent a new strategy for the treatment of HCC. Copyright © 2012 Elsevier Inc. All rights reserved.

Promising Nanocarriers for PEDF Gene Targeting Delivery to Cervical Cancer Cells Mediated by the Over-expressing FRα.

PubMed

Yang, Yuhan; He, Lili; Liu, Yongmei; Xia, Shan; Fang, Aiping; Xie, Yafei; Gan, Li; He, Zhiyao; Tan, Xiaoyue; Jiang, Chunling; Tong, Aiping; Song, Xiangrong

2016-08-31

Cervical cancer presents extremely low PEDF expression which is associated with tumor progression and poor prognosis. In this study, folate receptor α (FRα)-targeted nano-liposomes (FLP) were designed to enhance the anti-tumor effect by targeting delivery of exogenous PEDF gene to cervical cancer cells. The targeting molecule F-PEG-Chol was firstly synthesized by a novel simpler method. FLP encapsulating PEDF gene (FLP/PEDF) with a typical lipid-membrane structure were prepared by a film dispersion method. The transfection experiment found FLP could effectively transfect human cervical cancer cells (HeLa cells). FLP/PEDF significantly inhibited the growth of HeLa cells and human umbilical vein endothelial cells (HUVEC cells) and suppressed adhension, invasion and migration of HeLa cells in vitro. In the abdominal metastatic tumor model of cervical cancer, FLP/PEDF administered by intraperitoneal injection exhibited a superior anti-tumor effect probably due to the up-regulated PEDF. FLP/PEDF could not only sharply reduce the microvessel density but also dramatically inhibit proliferation and markedly induce apoptosis of tumor cells in vivo. Moreover, the preliminary safety investigation revealed that FLP/PEDF had no obvious toxicity. These results clearly showed that FLP were desired carriers for PEDF gene and FLP/PEDF might represent a potential novel strategy for gene therapy of cervical cancer.

The Anthelmintic Drug Niclosamide Induces Apoptosis, Impairs Metastasis and Reduces Immunosuppressive Cells in Breast Cancer Model

PubMed Central

Yan, Yupeng; Xia, Yong; Song, Xuejiao; Liu, Li; Li, Deliang; Wang, Ningyu; Zhang, Lidan; Zhu, Yongxia; Zeng, Jun; Wei, Yuquan; Yu, Luoting

2014-01-01

Breast carcinoma is the most common female cancer with considerable metastatic potential. Discovery of new therapeutic approaches for treatment of metastatic breast cancer is still needed. Here, we reported our finding with niclosamide, an FDA approved anthelmintic drug. The potency of niclosamide on breast cancer was assessed in vitro and in vivo. In this investigation, we found that niclosamide showed a dramatic growth inhibition against breast cancer cell lines and induced apoptosis of 4T1 cells in a dose-dependent manner. Further, Western blot analysis demonstrated the occurrence of its apoptosis was associated with activation of Cleaved caspases-3, down-regulation of Bcl-2, Mcl-1 and Survivin. Moreover, niclosamide blocked breast cancer cells migration and invasion, and the reduction of phosphorylated STAT3Tyr705, phosphorylated FAKTyr925 and phosphorylated SrcTyr416 were also observed. Furthermore, in our animal experiments, intraperitoneal administration of 20 mg/kg/d niclosamide suppressed 4T1 tumor growth without detectable toxicity. Histological and immunohistochemical analyses revealed a decrease in Ki67-positive cells, VEGF-positive cells and microvessel density (MVD) and an increase in Cleaved caspase-3-positive cells upon niclosamide. Notably, niclosamide reduced the number of myeloid-derived suppressor cells (MDSCs) in tumor tissues and blocked formation of pulmonary metastases. Taken together, these results demonstrated that niclosamide may be a promising candidate for breast cancer. PMID:24416452

Hypoxia-inducible vascular endothelial growth factor gene therapy using the oxygen-dependent degradation domain in myocardial ischemia.

PubMed

Kim, Hyun Ah; Lim, Soyeon; Moon, Hyung-Ho; Kim, Sung Wan; Hwang, Ki-Chul; Lee, Minhyung; Kim, Sun Hwa; Choi, Donghoon

2010-10-01

A hypoxia-inducible VEGF expression system with the oxygen-dependent degradation (ODD) domain was constructed and tested to be used in gene therapy for ischemic myocardial disease. Luciferase and VEGF expression vector systems were constructed with or without the ODD domain: pEpo-SV-Luc (or pEpo-SV-VEGF) and pEpo-SV-Luc-ODD (or pEpo-SV-VEGF-ODD). In vitro gene expression efficiency of each vector type was evaluated in HEK 293 cells under both hypoxic and normoxic conditions. The amount of VEGF protein was estimated by ELISA. The VEGF expression vectors with or without the ODD domain were injected into ischemic rat myocardium. Fibrosis, neovascularization, and cardiomyocyte apoptosis were assessed using Masson's trichrome staining, α-smooth muscle actin (α-SMA) immunostaining, and the TUNEL assay, respectively. The plasmid vectors containing ODD significantly improved the expression level of VEGF protein in hypoxic conditions. The enhancement of VEGF protein production was attributed to increased protein stability due to oxygen deficiency. In a rat model of myocardial ischemia, the pEpo-SV-VEGF-ODD group exhibited less myocardial fibrosis, higher microvessel density, and less cardiomyocyte apoptosis compared to the control groups (saline and pEpo-SV-VEGF treatments). An ODD-mediated VEGF expression system that facilitates VEGF-production under hypoxia may be useful in the treatment of ischemic heart disease.

In vivo evaluation of battery-operated light-emitting diode-based photodynamic therapy efficacy using tumor volume and biomarker expression as endpoints

NASA Astrophysics Data System (ADS)

Mallidi, Srivalleesha; Mai, Zhiming; Rizvi, Imran; Hempstead, Joshua; Arnason, Stephen; Celli, Jonathan; Hasan, Tayyaba

2015-04-01

In view of the increase in cancer-related mortality rates in low- to middle-income countries (LMIC), there is an urgent need to develop economical therapies that can be utilized at minimal infrastructure institutions. Photodynamic therapy (PDT), a photochemistry-based treatment modality, offers such a possibility provided that low-cost light sources and photosensitizers are available. In this proof-of-principle study, we focus on adapting the PDT light source to a low-resource setting and compare an inexpensive, portable, battery-powered light-emitting diode (LED) light source with a standard, high-cost laser source. The comparison studies were performed in vivo in a xenograft murine model of human squamous cell carcinoma subjected to 5-aminolevulinic acid-induced protoporphyrin IX PDT. We observed virtually identical control of the tumor burden by both the LED source and the standard laser source. Further insights into the biological response were evaluated by biomarker analysis of necrosis, microvessel density, and hypoxia [carbonic anhydrase IX (CAIX) expression] among groups of control, LED-PDT, and laser-PDT treated mice. There is no significant difference in the percent necrotic volume and CAIX expression in tumors that were treated with the two different light sources. These encouraging preliminary results merit further investigations in orthotopic animal models of cancers prevalent in LMICs.

Clinical and Pathological Significance of ER Stress Marker (BiP/GRP78 and PERK) Expression in Malignant Melanoma.

PubMed

Shimizu, Akira; Kaira, Kyoichi; Yasuda, Masahito; Asao, Takayuki; Ishikawa, Osamu

2017-01-01

Glucose-regulated protein of 78 kD (GRP78) also referred to as immunoglobulin heavy chain binding protein (BiP/GRP78) plays an important role in the endoplasmic reticulum (ER) stress. The level of BiP/GRP78 is highly elevated in various human cancers. The purpose of this study is to examine the prognostic significance of BiP/GRP78 expression in patients with malignant melanoma. A total of 133 malignant melanoma patients were analyzed, and tumor specimens were stained by immunohistochemistry for BiP/GRP78, PKR-like endoplasmic reticulum kinase (PERK), Ki-67, p53 and microvessel density (MVD) determined by CD34. BiP/GRP78 and PERK were highly expressed in 40 % (53/133) and 78 % (104/133), respectively. BiP/GRP78 disclosed a significant relationship with PERK expression, thickness, T factor, N factor, disease staging, cell proliferation (Ki-67) and MVD (CD34). By multivariate analysis, the high expression of BiP/GRP78 was identified as an independent prognostic factor for predicting poor survival against malignant melanoma. The increased BiP/GRP78 expression was clarified as an independent prognostic marker for predicting worse outcome. ER stress marker, BiP/GRP78 could be a powerful molecular target for the treatment of malignant melanoma.

Angiogenesis in a human neuroblastoma xenograft model: mechanisms and inhibition by tumour-derived interferon-γ

PubMed Central

Ribatti, D; Nico, B; Pezzolo, A; Vacca, A; Meazza, R; Cinti, R; Carlini, B; Parodi, F; Pistoia, V; Corrias, M V

2006-01-01

Tumour progression in neuroblastoma (NB) patients correlates with high vascular index. We have previously shown that the ACN NB cell line is tumorigenic and angiogenic in immunodeficient mice, and that interferon-γ (IFN-γ) gene transfer dampens ACN tumorigenicity. As IFN-γ represses lymphocyte-induced tumour angiogenesis in various murine models and inhibits proliferation and migration of human endothelial cells, we have investigated the antiangiogenic activity of tumour-derived IFN-γ and the underlying mechanism(s). In addition, we characterised the tumour vasculature of the ACN xenografts, using the chick embryo chorioallantoic membrane assay. We show that the ACN/IFN-γ xenografts had a lower microvessel density and less in vivo angiogenic potential than the vector-transfected ACN/neo. The vascular channels of both xenografts were formed by a mixed endothelial cell population of murine and human origin, as assessed by the FICTION (fluorescence immunophenotyping and interphase cytogenetics) technique. With respect to ACN/neo, the ACN/IFN-γ xenografts showed more terminal deoxynucleotidyl transferase-mediated dUTP nick end labelling-positive human and murine endothelial cells, suggesting that inhibition of angiogenesis by IFN-γ was dependent on the induction of apoptosis, likely mediated by nitric oxide. Once the dual origin of tumour vasculature is confirmed in NB patients, the xenograft model described here will prove useful in testing the efficacy of different antiangiogenic compounds. PMID:16721359

Expression of pigment epithelium-derived factor and tumor necrosis factor-α is correlated in bladder tumor and is related to tumor angiogenesis.

PubMed

Feng, Chen-Chen; Wang, Pao-Hsun; Ding, Qiang; Guan, Ming; Zhang, Yuan-Fang; Jiang, Hao-Wen; Wen, Hui; Wu, Zhong

2013-02-01

Angiogenesis is a pivotal process on which solid tumor growth is substantially dependent. Pigment epithelium-derived factor (PEDF) is the most potent natural anti-angiogenic factor, which has seldom been studied in bladder tumor, and whose functioning pathway remains unclear. We have thus investigated PEDF expression in relation to tumor necrosis factor-α (TNF-α) and microvessel density (MVD) with immunohistochemistry. Antibodies of PEDF and TNF-α were examined by Western blotting before immunohistochemistry. Sixty-four urothelial tumor sections and 23 normal controls were stained and expression of PEDF, TNF-α, and MVD were studied. Decreased PEDF expression and increased TNF-α expression was noticed in tumorous tissue compared with healthy urothelium. Lower PEDF expression was related to higher tumor grade but stage. Increased TNF-α expression was noticed in recurrent, larger tumors as well as in tumors with progression in grade and stage. Expression of PEDF and TNF-α was correlated in bladder tumor. PEDF or TNF-α was correlated with MVD negatively or positively, respectively, in cancerous tissue and tumorous grouping without correlation in papillary urothelial neoplasm of low malignant potential. Expressional change of PEDF and TNF-α is in relation to angiogenesis of bladder tumor, especially in bladder cancer development. Copyright © 2013 Elsevier Inc. All rights reserved.

Preparation, characterization, in vitro and in vivo anti-tumor effect of thalidomide nanoparticles on lung cancer.

PubMed

Chen, Long Xia; Ni, Xiao Ling; Zhang, Heng; Wu, Min; Liu, Jing; Xu, Shan; Yang, Ling Lin; Fu, Shao Zhi; Wu, Jingbo

2018-01-01

Thalidomide (THA) is an angiogenesis inhibitor and an efficient inhibitor of the tumor necrosis factor-α (TNF-α). However, the clinical application of THA has been limited due to hydrophobicity of the compound. To increase the water solubility of THA and in order to evaluate the anticancer abilities of this material on human lung carcinoma, methoxy poly(ethylene glycol)-poly(ε-caprolactone) nanoparticles loaded with THA (THA-NPs) were prepared. The synthesis of THA-NPs was carried out via a dialysis method with relative satisfactory encapsulation efficiency, loading capacity, size distribution, and zeta potential. A cytotoxicity assay demonstrated that THA-NPs inhibited the growth of cells in a dose-dependent manner. The evaluation of anti-tumor activity in vivo showed that THA-NPs could inhibit tumor growth and prolong the survival rate of tumor-bearing mice. Immunohistochemical analysis indicated that THA-NPs inhibited cell proliferation (Ki-67 positive rate, 32.8%±4.2%, P <0.01), and resulted in a decreased rate of the tumor tissue microvessel density (3.87%±0.77%, P <0.01), VEGF (26.67%±4.02%, P <0.01), and TNF-α (75.21±6.85 ng/mL, P <0.01). In general, the drug delivery system reported herein may shed light on future targeted therapy in lung cancer treatment.

FH535, a β-catenin pathway inhibitor, represses pancreatic cancer xenograft growth and angiogenesis

PubMed Central

Gong, Fei-Ran; Zhou, Binhua P.; Lian, Lian; Shen, Bairong; Chen, Kai; Duan, Weiming; Wu, Meng-Yao; Tao, Min; Li, Wei

2016-01-01

The WNT/β-catenin pathway plays an important role in pancreatic cancer carcinogenesis. We evaluated the correlation between aberrant β-catenin pathway activation and the prognosis pancreatic cancer, and the potential of applying the β-catenin pathway inhibitor FH535 to pancreatic cancer treatment. Meta-analysis and immunohistochemistry showed that abnormal β-catenin pathway activation was associated with unfavorable outcome. FH535 repressed pancreatic cancer xenograft growth in vivo. Gene Ontology (GO) analysis of microarray data indicated that target genes responding to FH535 participated in stemness maintenance. Real-time PCR and flow cytometry confirmed that FH535 downregulated CD24 and CD44, pancreatic cancer stem cell (CSC) markers, suggesting FH535 impairs pancreatic CSC stemness. GO analysis of β-catenin chromatin immunoprecipitation sequencing data identified angiogenesis-related gene regulation. Immunohistochemistry showed that higher microvessel density correlated with elevated nuclear β-catenin expression and unfavorable outcome. FH535 repressed the secretion of the proangiogenic cytokines vascular endothelial growth factor (VEGF), interleukin (IL)-6, IL-8, and tumor necrosis factor-α, and also inhibited angiogenesis in vitro and in vivo. Protein and mRNA microarrays revealed that FH535 downregulated the proangiogenic genes ANGPT2, VEGFR3, IFN-γ, PLAUR, THPO, TIMP1, and VEGF. FH535 not only represses pancreatic CSC stemness in vitro, but also remodels the tumor microenvironment by repressing angiogenesis, warranting further clinical investigation. PMID:27323403

Microcomputed tomography characterization of neovascularization in bone tissue engineering applications.

PubMed

Young, Simon; Kretlow, James D; Nguyen, Charles; Bashoura, Alex G; Baggett, L Scott; Jansen, John A; Wong, Mark; Mikos, Antonios G

2008-09-01

Vasculogenesis and angiogenesis have been studied for decades using numerous in vitro and in vivo systems, fulfilling the need to elucidate the mechanisms involved in these processes and to test potential therapeutic agents that inhibit or promote neovascularization. Bone tissue engineering in particular has benefited from the application of proangiogenic strategies, considering the need for an adequate vascular supply during healing and the challenges associated with the vascularization of scaffolds implanted in vivo. Conventional methods of assessing the in vivo angiogenic response to tissue-engineered constructs tend to rely on a two-dimensional assessment of microvessel density within representative histological sections without elaboration of the true vascular tree. The introduction of microcomputed tomography (micro-CT) has recently allowed investigators to obtain a diverse range of high-resolution, three-dimensional characterization of structures, including renal, coronary, and hepatic vascular networks, as well as bone formation within healing defects. To date, few studies have utilized micro-CT to study the vascular response to an implanted tissue engineering scaffold. In this paper, conventional in vitro and in vivo models for studying angiogenesis will be discussed, followed by recent developments in the use of micro-CT for vessel imaging in bone tissue engineering research. A new study demonstrating the potential of contrast-enhanced micro-CT for the evaluation of in vivo neovascularization in bony defects is described, which offers significant potential in the evaluation of bone tissue engineering constructs.

Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, Seo-Hyun; Nam, Jae-Kyung; Jang, Junho

Radiotherapy is a widely used treatment for many tumors. Combination therapy using anti-angiogenic agents and radiation has shown promise; however, these combined therapies are reported to have many limitations in clinical trials. Here, we show that radiation transformed tumor endothelial cells (ECs) to fibroblasts, resulting in reduced vascular endothelial growth factor (VEGF) response and increased Snail1, Twist1, Type I collagen, and transforming growth factor (TGF)-β release. Irradiation of radioresistant Lewis lung carcinoma (LLC) tumors greater than 250 mm{sup 3} increased collagen levels, particularly in large tumor vessels. Furthermore, concomitant sunitinib therapy did not show a significant difference in tumor inhibition versusmore » radiation alone. Thus, we evaluated multimodal therapy that combined pirfenidone, an inhibitor of TGF-induced collagen production, with radiation and sunitinib treatment. This trimodal therapy significantly reduced tumor growth, as compared to radiation alone. Immunohistochemical analysis revealed that radiation-induced collagen deposition and tumor microvessel density were significantly reduced with trimodal therapy, as compared to radiation alone. These data suggest that combined therapy using pirfenidone may modulate the radiation-altered tumor microenvironment, thereby enhancing the efficacy of radiation therapy and concurrent chemotherapy. - Highlights: • Radiation changes tumor endothelial cells to fibroblasts. • Radio-resistant tumors contain collagen deposits, especially in tumor vessels. • Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy. • Pirfenidone reduces radiation-induced collagen deposits in tumors.« less

Topical application of substance P promotes wound healing in streptozotocin-induced diabetic rats.

PubMed

Kant, Vinay; Kumar, Dinesh; Kumar, Dhirendra; Prasad, Raju; Gopal, Anu; Pathak, Nitya N; Kumar, Pawan; Tandan, Surender K

2015-05-01

Substance P (SP) is known to stimulate angiogenesis, fibroblasts proliferation and expressions of cytokines and growth factors involved in wound healing. However, SP level reduces in dermis in diabetics and, hence, it was hypothesized that exogenously applied SP could be helpful in improving wound healing in diabetic rats. Excision skin wound was created on the back of diabetic rats and rats were divided into three groups i.e. (i) saline-, (ii) gel- and (iii) SP-treated. Normal saline, pluronic gel and SP (10(-6)M) in gel were topically applied once daily for 19days. SP treatment significantly increased the wound closure, levels of interleukin-10, and expressions of vascular endothelial growth factor, transforming growth factor-beta1, heme oxygenase-1 and endothelial nitric oxide synthase, whereas it significantly decreased the expression of tumor necrosis factor-alpha, interleukin-1beta and matrix metalloproteinases-9 in the granulation/healing tissue. The inflammatory cells were present for long time in normal saline-treated group. Histological evaluation revealed better extracellular matrix formation with marked fibroblast proliferation and collagen deposition in SP-treated group. Early epithelial layer formation, increased microvessel density and greater growth associated protein-43 positive nerve fibers were also evidenced in SP-treated group. In conclusion, SP treatment markedly accelerated cutaneous wound healing in diabetic rats. Copyright © 2014 Elsevier Ltd. All rights reserved.

Pulmonary emphysema and tumor microenvironment in primary lung cancer.

PubMed

Murakami, Junichi; Ueda, Kazuhiro; Sano, Fumiho; Hayashi, Masataro; Nishimoto, Arata; Hamano, Kimikazu

2016-02-01

To clarify the relationship between the presence of pulmonary emphysema and tumor microenvironment and their significance for the clinicopathologic aggressiveness of non-small cell lung cancer. The subjects included 48 patients with completely resected and pathologically confirmed stage I non-small cell lung cancer. Quantitative computed tomography was used to diagnose pulmonary emphysema, and immunohistochemical staining was performed to evaluate the matrix metalloproteinase (MMP) expression status in the intratumoral stromal cells as well as the microvessel density (MVD). Positive MMP-9 staining in the intratumoral stromal cells was confirmed in 17 (35%) of the 48 tumors. These 17 tumors were associated with a high MVD, frequent lymphovascular invasion, a high proliferative activity, and high postoperative recurrence rate (all, P < 0.05). The majority of the tumors (13 of 17) arose in patients with pulmonary emphysema (P = 0.02). Lung cancers arising from pulmonary emphysema were also associated with a high MVD, proliferative activity, and postoperative recurrence rate (all, P < 0.05). The MMP-9 expression in intratumoral stromal cells is associated with the clinicopathologic aggressiveness of lung cancer and is predominantly identified in tumors arising in emphysematous lungs. Further studies regarding the biological links between the intratumoral and extratumoral microenvironment will help to explain why lung cancers originating in emphysematous lung tissues are associated with a poor prognosis. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of combined mesenchymal stem cells and heme oxygenase-1 therapy on cardiac performance.

PubMed

Zeng, Bin; Chen, Honglei; Zhu, Chengang; Ren, Xiaofeng; Lin, Guosheng; Cao, Feng

2008-10-01

Bone marrow mesenchymal stem cells (MSCs) have the potential to repair the infarcted myocardium and improve cardiac function. However, this approach is limited by its poor viability after transplantation, and controversy still exists over the mechanism by which MSCs contribute to the tissue repair. The human heme oxygenase-1 (hHO-1) was transfected into cultured MSCs using an adenoviral vector. 1 x 10(6) Ad-hHO-1-transfected MSCs (HO-1-MSCs) or Ad-Null-transfected MSCs (Null-MSCs) or PBS only (PBS group) were injected intramyocardially into rat hearts 1h after myocardial infarction. HO-1-MSCs survived in the infarcted myocardium, and expressed hHO-1 mRNA. The expression of basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) was significantly enhanced in HO-1-MSCs-treated hearts. At the same time, there were significant reduction of TNF-alpha, IL-1-beta and IL-6 mRNA, and marked increase of IL-10 mRNA in HO-1-MSCs-treated hearts. Moreover, a further downregulation of proapoptotic protein, Bax, and a marked increase in microvessel density were observed in HO-1-MSCs-treated hearts. The infarct size and cardiac performance were also significantly improved in HO-1-MSCs-treated hearts. The combined approach improves MSCs survival and is superior to MSCs injection alone.

Hypoxia-activated chemotherapeutic TH-302 enhances the effects of VEGF-A inhibition and radiation on sarcomas.

PubMed

Yoon, C; Lee, H-J; Park, D J; Lee, Y-J; Tap, W D; Eisinger-Mathason, T S K; Hart, C P; Choy, E; Simon, M C; Yoon, S S

2015-06-30

Human sarcomas with a poor response to vascular endothelial growth factor-A (VEGF-A) inhibition and radiation therapy (RT) have upregulation of hypoxia-inducible factor 1α (HIF-1α) and HIF-1α target genes. This study examines the addition of the hypoxia-activated chemotherapy TH-302 to VEGF-A inhibition and RT (a.k.a. trimodality therapy). Trimodality therapy was examined in two xenograft models and in vitro in tumour endothelial cells and sarcoma cell lines. In both mouse models, VEGF-A inhibition and radiation showed greater efficacy than either therapy alone in slowing sarcoma growth. When TH-302 was added, this trimodality therapy completely blocked tumour growth with tumours remaining dormant for over 3 months after cessation of therapy. Trimodality therapy caused 2.6- to 6.2-fold more endothelial cell-specific apoptosis than bimodality therapies, and microvessel density and HIF-1α activity were reduced to 11-13% and 13-20% of control, respectively. When trimodality therapy was examined in vitro, increases in DNA damage and apoptosis were much more pronounced in tumour endothelial cells compared with that in sarcoma cells, especially under hypoxia. The combination of TH-302, VEGF-A inhibition, and RT is highly effective in preclinical models of sarcoma and is associated with increased DNA damage and apoptosis in endothelial cells and decreased HIF-1α activity.

Promising Nanocarriers for PEDF Gene Targeting Delivery to Cervical Cancer Cells Mediated by the Over-expressing FRα

PubMed Central

Yang, Yuhan; He, Lili; Liu, Yongmei; Xia, Shan; Fang, Aiping; Xie, Yafei; Gan, Li; He, Zhiyao; Tan, Xiaoyue; Jiang, Chunling; Tong, Aiping; Song, Xiangrong

2016-01-01

Cervical cancer presents extremely low PEDF expression which is associated with tumor progression and poor prognosis. In this study, folate receptor α (FRα)-targeted nano-liposomes (FLP) were designed to enhance the anti-tumor effect by targeting delivery of exogenous PEDF gene to cervical cancer cells. The targeting molecule F-PEG-Chol was firstly synthesized by a novel simpler method. FLP encapsulating PEDF gene (FLP/PEDF) with a typical lipid-membrane structure were prepared by a film dispersion method. The transfection experiment found FLP could effectively transfect human cervical cancer cells (HeLa cells). FLP/PEDF significantly inhibited the growth of HeLa cells and human umbilical vein endothelial cells (HUVEC cells) and suppressed adhension, invasion and migration of HeLa cells in vitro. In the abdominal metastatic tumor model of cervical cancer, FLP/PEDF administered by intraperitoneal injection exhibited a superior anti-tumor effect probably due to the up-regulated PEDF. FLP/PEDF could not only sharply reduce the microvessel density but also dramatically inhibit proliferation and markedly induce apoptosis of tumor cells in vivo. Moreover, the preliminary safety investigation revealed that FLP/PEDF had no obvious toxicity. These results clearly showed that FLP were desired carriers for PEDF gene and FLP/PEDF might represent a potential novel strategy for gene therapy of cervical cancer. PMID:27576898

NOTCH3 Is Induced in Cancer-Associated Fibroblasts and Promotes Angiogenesis in Oral Squamous Cell Carcinoma.

PubMed

Kayamori, Kou; Katsube, Ken-Ichi; Sakamoto, Kei; Ohyama, Yoshio; Hirai, Hideaki; Yukimori, Akane; Ohata, Yae; Akashi, Takumi; Saitoh, Masao; Harada, Kiyoshi; Harada, Hiroyuki; Yamaguchi, Akira

2016-01-01

Recent studies have shown that Notch signaling is involved in many types of cancers, including oral squamous cell carcinomas (OSCCs). However, the role of Notch signaling in the tumor microenvironment is not yet fully understood. In this study, we investigated the roles of NOTCH3 signaling in cancer associated fibroblasts (CAFs) in OSCCs. Immunohistochemical study of 93 human tongue OSCC cases indicated that about one third of OSCCs showed NOTCH3 expression in CAFs, and that this expression significantly correlated with tumor-size. In vitro study showed that OSCC cell lines, especially HO1-N-1 cells stimulated NOTCH3 expression in normal human dermal fibroblasts (NHDFs) through direct cell-to-cell contact. Immunohistochemical and morphometric analysis using human OSCC samples demonstrated that NOTCH3 expression in CAFs significantly correlated with micro-vessel density in cancer stroma. In vitro angiogenesis assays involving co-culture of NHDFs with HO1-N-1 and human umbilical endothelial cells (HUVECs), and NOTCH3 knockdown in NHDFs using siRNA, demonstrated that HO1-N-1 cells significantly promoted tube formation dependent on NOTCH3-expression in NHDFs. Moreover, NOTCH3 expression in CAFs was related to poor prognosis of the OSCC patients. This work provides a new insight into the role of Notch signaling in CAFs associated with tumor angiogenesis and the possibility of NOTCH3-targeted molecular therapy in OSCCs.

NOTCH3 Is Induced in Cancer-Associated Fibroblasts and Promotes Angiogenesis in Oral Squamous Cell Carcinoma

PubMed Central

Kayamori, Kou; Katsube, Ken-ichi; Sakamoto, Kei; Ohyama, Yoshio; Hirai, Hideaki; Yukimori, Akane; Ohata, Yae; Akashi, Takumi; Saitoh, Masao; Harada, Kiyoshi; Harada, Hiroyuki; Yamaguchi, Akira

2016-01-01

Recent studies have shown that Notch signaling is involved in many types of cancers, including oral squamous cell carcinomas (OSCCs). However, the role of Notch signaling in the tumor microenvironment is not yet fully understood. In this study, we investigated the roles of NOTCH3 signaling in cancer associated fibroblasts (CAFs) in OSCCs. Immunohistochemical study of 93 human tongue OSCC cases indicated that about one third of OSCCs showed NOTCH3 expression in CAFs, and that this expression significantly correlated with tumor-size. In vitro study showed that OSCC cell lines, especially HO1-N-1 cells stimulated NOTCH3 expression in normal human dermal fibroblasts (NHDFs) through direct cell-to-cell contact. Immunohistochemical and morphometric analysis using human OSCC samples demonstrated that NOTCH3 expression in CAFs significantly correlated with micro-vessel density in cancer stroma. In vitro angiogenesis assays involving co-culture of NHDFs with HO1-N-1 and human umbilical endothelial cells (HUVECs), and NOTCH3 knockdown in NHDFs using siRNA, demonstrated that HO1-N-1 cells significantly promoted tube formation dependent on NOTCH3-expression in NHDFs. Moreover, NOTCH3 expression in CAFs was related to poor prognosis of the OSCC patients. This work provides a new insight into the role of Notch signaling in CAFs associated with tumor angiogenesis and the possibility of NOTCH3-targeted molecular therapy in OSCCs. PMID:27124156

Neovascularization and Angiogenic Gene Expression Following Chronic Arsenic Exposure in Mice

PubMed Central

Soucy, Nicole V.; Mayka, Debra; Klei, Linda R.; Nemec, Antonia A.; Bauer, John A.; Barchowsky, Aaron

2015-01-01

Exposure to arsenic in drinking water increases incidence of cardiovascular diseases. However, the basic mechanisms and genetic changes that promote these diseases are unknown. This study investigated the effects of chronic arsenic exposure on vessel growth and expression of angiogenic and tissue remodeling genes in cardiac tissues. Male mice were exposed to low to moderately high levels of arsenite (AsIII) for 5, 10, or 20 wk in their drinking water. Vessel growth in Matrigel implants was tested during the last 2 wk of each exposure period. Implant vascularization increased in mice exposed to 5–500 ppb AsIII for 5 wk. Similar increases were seen following exposure to 50–250 ppb of AsIII over 20 wk, but the response to 500 ppb decreased with time. RT-PCR analysis of cardiac mRNA revealed differential expression of angiogenic or tissue remodeling genes, such as vascular endothelial cell growth factor (VEGF), VEGF receptors, plasminogen activator inhibitor-1, endothelin-1, and matrix metalloproteinase-9, which varied with time or amount of exposure. VEGF receptor mRNA and cardiac microvessel density were reduced by exposure to 500 ppb AsIII for 20 wk. These data demonstrate differential concentration and time-dependent effects of chronic arsenic exposure on cardiovascular phenotype and vascular remodeling that may explain the etiology for AsIII-induced disease. PMID:15738583

Pleiotrophin promotes vascular abnormalization in gliomas and correlates with poor survival in patients with astrocytomas.

PubMed

Zhang, Lei; Kundu, Soumi; Feenstra, Tjerk; Li, Xiujuan; Jin, Chuan; Laaniste, Liisi; El Hassan, Tamador Elsir Abu; Ohlin, K Elisabet; Yu, Di; Olofsson, Tommie; Olsson, Anna-Karin; Pontén, Fredrik; Magnusson, Peetra U; Nilsson, Karin Forsberg; Essand, Magnus; Smits, Anja; Dieterich, Lothar C; Dimberg, Anna

2015-12-08

Glioblastomas are aggressive astrocytomas characterized by endothelial cell proliferation and abnormal vasculature, which can cause brain edema and increase patient morbidity. We identified the heparin-binding cytokine pleiotrophin as a driver of vascular abnormalization in glioma. Pleiotrophin abundance was greater in high-grade human astrocytomas and correlated with poor survival. Anaplastic lymphoma kinase (ALK), which is a receptor that is activated by pleiotrophin, was present in mural cells associated with abnormal vessels. Orthotopically implanted gliomas formed from GL261 cells that were engineered to produce pleiotrophin showed increased microvessel density and enhanced tumor growth compared with gliomas formed from control GL261 cells. The survival of mice with pleiotrophin-producing gliomas was shorter than that of mice with gliomas that did not produce pleiotrophin. Vessels in pleiotrophin-producing gliomas were poorly perfused and abnormal, a phenotype that was associated with increased deposition of vascular endothelial growth factor (VEGF) in direct proximity to the vasculature. The growth of pleiotrophin-producing GL261 gliomas was inhibited by treatment with the ALK inhibitor crizotinib, the ALK inhibitor ceritinib, or the VEGF receptor inhibitor cediranib, whereas control GL261 tumors did not respond to either inhibitor. Our findings link pleiotrophin abundance in gliomas with survival in humans and mice, and show that pleiotrophin promotes glioma progression through increased VEGF deposition and vascular abnormalization. Copyright © 2015, American Association for the Advancement of Science.

The biguanides metformin and phenformin inhibit angiogenesis, local and metastatic growth of breast cancer by targeting both neoplastic and microenvironment cells.

PubMed

Orecchioni, Stefania; Reggiani, Francesca; Talarico, Giovanna; Mancuso, Patrizia; Calleri, Angelica; Gregato, Giuliana; Labanca, Valentina; Noonan, Douglas M; Dallaglio, Katiuscia; Albini, Adriana; Bertolini, Francesco

2015-03-15

The human white adipose tissue (WAT) contains progenitors with cooperative roles in breast cancer (BC) angiogenesis, local and metastatic progression. The biguanide Metformin (Met), commonly used for Type 2 diabetes, might have activity against BC and was found to inhibit angiogenesis in vivo. We studied Met and another biguanide, phenformin (Phe), in vitro and in vivo in BC models. In vitro, biguanides activated AMPK, inhibited Complex 1 of the respiratory chain and induced apoptosis of BC and WAT endothelial cells. In coculture, biguanides inhibited the production of several angiogenic proteins. In vivo, biguanides inhibited local and metastatic growth of triple negative and HER2+ BC in immune-competent and immune-deficient mice orthotopically injected with BC. Biguanides inhibited local and metastatic BC growth in a genetically engineered murine model model of HER2+ BC. In vivo, biguanides increased pimonidazole binding (but not HIF-1 expression) of WAT progenitors, reduced tumor microvessel density and altered the vascular pericyte/endothelial cell ratio, so that cancer vessels displayed a dysplastic phenotype. Phe was significantly more active than Met both in vitro and in vivo. Considering their safety profile, biguanides deserve to be further investigated for BC prevention in high-risk subjects, in combination with chemo and/or targeted therapy and/or as post-therapy consolidation or maintenance therapy for the prevention of BC recurrence. © 2014 UICC.

Multiparametric Monitoring of Early Response to Antiangiogenic Therapy: A Sequential Perfusion CT and PET/CT Study in a Rabbit VX2 Tumor Model

PubMed Central

Lee, Hyun-Ju; Lee, Kyung Won; Lee, Hak Jong; Lee, Won Woo

2014-01-01

Objectives. To perform dual analysis of tumor perfusion and glucose metabolism using perfusion CT and FDG-PET/CT for the purpose of monitoring the early response to bevacizumab therapy in rabbit VX2 tumor models and to assess added value of FDG-PET to perfusion CT. Methods. Twenty-four VX2 carcinoma tumors implanted in bilateral back muscles of 12 rabbits were evaluated. Serial concurrent perfusion CT and FDG-PET/CT were performed before and 3, 7, and 14 days after bevacizumab therapy (treatment group) or saline infusion (control group). Perfusion CT was analyzed to calculate blood flow (BF), blood volume (BV), and permeability surface area product (PS); FDG-PET was analyzed to calculate SUVmax, SUVmean, total lesion glycolysis (TLG), entropy, and homogeneity. The flow-metabolic ratio (FMR) was also calculated and immunohistochemical analysis of microvessel density (MVD) was performed. Results. On day 14, BF and BV in the treatment group were significantly lower than in the control group. There were no significant differences in all FDG-PET-derived parameters between both groups. In the treatment group, FMR prominently decreased after therapy and was positively correlated with MVD. Conclusions. In VX2 tumors, FMR could provide further insight into the early antiangiogenic effect reflecting a mismatch in intratumor blood flow and metabolism. PMID:25383376

Inhibition of hemangioma growth using polymer-lipid hybrid nanoparticles for delivery of rapamycin.

PubMed

Li, Haitao; Teng, Yunfei; Sun, Jin; Liu, Jianyong

2017-11-01

Although infantile hemangiomas is benign, its rapid growth may induce serious complications. However, only one drug Hemangeol™ has been approved by US Food and Drug Administration (FDA) to treat infantile hemangiomas. Thus it is necessary to develop novel alternative drugs to treat infantile hemangiomas. Rapamycin is a well-know potent antiangiogenic agent, whereas the daily oral administration of rapamycin exerts undesired metabolic effects due to its inhibition of mechanistic target of rapamycin (mTOR) which is critical in cell metabolism. We hereby developed rapamycin-loaded polymer-lipid hybrid nanoparticles (Rapamycin-PLNPs) as a local controlled release system to realize local and sustained release of rapamycin, aiming to reduce the side effects and frequency of administration of rapamycin. Rapamycin-PLNPs are of a small size (129.1nm), desired drug encapsulation efficiency (63.7%), and sustained drug release for 5 days. Rapamycin-PLNPs were shown to be able to effectively bind to hemangioma endothelia cells (HemECs), induce significant proliferation inhibition and reduce expression of angiogenesis factors in HemECs. The therapeutic effect of Rapamycin-PLNPs against infantile hemangioma in vivo was superior to rapamycin, as reflected by reduced hemangioma volume, weight and microvessel density. Taken together, Rapamycin-PLNPs represent a very promising local approach in the treatment of infantile hemangiomas. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Expression and clinical significance of matrix metalloproteinase-9 in lymphatic invasiveness and metastasis of breast cancer.

PubMed

Wu, Qiu-Wan; Yang, Qing-Mo; Huang, Yu-Fan; She, Hong-Qiang; Liang, Jing; Yang, Qiao-Lu; Zhang, Zhi-Ming

2014-01-01

Matrix metalloproteinase 9 (MMP-9) is a type-IV collagenase that is highly expressed in breast cancer, but its exact role in tumor progression and metastasis is unclear. MMP-9 mRNA and protein expression was examined by real-time reverse transcriptase PCR and immunohistochemical staining, respectively, in 41 breast cancer specimens with matched peritumoral benign breast epithelial tissue and suspicious metastatic axillary lymph nodes. Lymph vessels were labeled with D2-40 and lymphatic microvessel density (LMVD) was calculated. Correlation of MMP-9 protein expression with clinicopathological parameters and LMVD was also evaluated. MMP-9(+) staining in breast cancer specimens (35/41, 85.4%) was higher than in matched epithelium (21/41, 51.2%; P<0.05) and lymph nodes (13/41, 31.7%; P<0.001). Higher MMP-9 mRNA expression was also detected in tumor specimens compared with matched epithelial tissues and lymph nodes (P<0.05). Elevated MMP-9 expression was correlated with lymph node metastasis and LMVD (P<0.05). MMP-9 was overexpressed in breast cancer specimens compared with peritumoral benign breast epithelium and lymph nodes. Moreover, its expression in the matched epithelium and lymph nodes was positively associated with lymph node metastasis, and its expression in lymph nodes was positively associated with lymphangiogenesis in breast cancer. Thus, MMP-9 is a potential marker for breast cancer progression.

Serum levels, and bone marrow immunohistochemical expression of, vascular endothelial growth factor in patients with chronic myeloproliferative diseases.

PubMed

Panteli, Katerina; Bai, Maria; Hatzimichael, Eleftheria; Zagorianakou, Nektaria; Agnantis, Niki John; Bourantas, Konstantinos

2007-12-01

Current data suggest that angiogenesis plays a significant role in the pathogenesis and progression of chronic myeloproliferative diseases (cMPDs). In the present study, we evaluated serum levels of vascular endothelial growth factor (VEGF) in 83 patients with cMPDs [myelofibrosis with myeloid metaplasia (MMM, n = 25), essential thrombocythaemia (ET, n = 40), polycythaemia vera (PV, n = 8) and chronic myeloid leukemia (CML, n = 10)] and in 27 healthy individuals. Serum VEGF levels were significantly increased in patients with cMPDs compared to healthy individuals (all p values were < or = 0.05) and were significantly correlated with bone marrow microvessel density (MVD) (p = 0.0013). In addition, the immunohistochemical expression of VEGF protein in bone marrow biopsy specimens were analyzed in 61 patients with cMPDs, (ET, n = 36 and MMM, n = 25) and in 27 healthy individuals. The cellular distribution of VEGF expression was similar in bone marrow specimens of patients and healthy individuals. VEGF protein was detected mainly in erythroid cells, whereas myeloid cells and megakaryocytes exhibited a variable expression of the protein. The percentage of bone marrow VEGF positive cells was positively correlated with serum levels of VEGF (p = 0.001). The results of the present study suggest that, VEGF is a major angiogenetic factor in patients with cMPDs and contributes to the pathogenesis of these diseases.

Angiogenesis in chronic myeloproliferative diseases detected by CD34 expression.

PubMed

Panteli, K; Zagorianakou, N; Bai, M; Katsaraki, A; Agnantis, N J; Bourantas, K

2004-06-01

Increased bone marrow angiogenesis estimated as bone marrow microvessel density (MVD), or as serum angiogenic factor levels and/or immunohistochemical expression of these factors in bone marrow biopsy has been demonstrated in a variety of hematological disorders including chronic myeloproliferative diseases (MPDs). The aim of this study was to investigate the MVD in 25 cases of myelofibrosis with myeloid metaplasia (MMM). MVD was estimated by CD34 immunohistochemical expression in bone marrow biopsies. A control group of 27 patients without bone marrow disease, eight cases of polycythemia vera (PV), 41 cases of essential thrombocythemia (ET) and nine cases of chronic myeloid leukemia (CML) were also studied. Moreover, in cases with MMM, MVD was correlated with clinical, laboratory, histological parameters and the outcome of the patients. Our study confirmed a significantly higher degree of angiogenesis in MMM, PV, ET and CML compared with controls (P < 0.001, P = 0.0007, P < 0.001 and P = 0.0008, respectively). Angiogenesis was higher in MMM than PV, ET and CML cases (P < 0.001, P < 0.001 and P = 0.008). Increased angiogenesis was correlated with hypercatabolic symptoms in MMM patients (P = 0.009). No correlation with other clinicopathological parameters or clinical outcome was found. However, definitive conclusions regarding the prognostic value of increased angiogenesis may require additional follow-up and a larger group of patients.

Role of Proinflammatory Cytokines in Thermal Activation of Lymphocyte Recruitment to Breast Tumor Microvessels

DTIC Science & Technology

2007-03-01

Photomicrographs show typical images. Scale bar, 50 µm. Data are the mean ± SE and are representative of ≥ 3 independent experiments. P values represent the...not affect ICAM-1 expression in normal islets of RIP-Tag5 pancreas. Photomicrographs show typical images. Scale bar, 50 µm. 2 We have identified the...WBH-treated mice. Thermal upregulation of vascular ICAM-1 expression was abolished in IL-6 KO mice. Photomicrographs show typical images. Scale bar

Shock Initiation Experiments with Ignition and Growth Modeling on the HMX-Based Explosive LX-14

NASA Astrophysics Data System (ADS)

Vandersall, Kevin S.; Dehaven, Martin R.; Strickland, Shawn L.; Tarver, Craig M.; Springer, H. Keo; Cowan, Matt R.

2017-06-01

Shock initiation experiments on the HMX-based explosive LX-14 were performed to obtain in-situ pressure gauge data, characterize the run-distance-to-detonation behavior, and provide a basis for Ignition and Growth reactive flow modeling. A 101 mm diameter gas gun was utilized to initiate the explosive charges with manganin piezoresistive pressure gauge packages placed between sample disks pressed to different densities ( 1.57 or 1.83 g/cm3 that corresponds to 85 or 99% of theoretical maximum density (TMD), respectively). The shock sensitivity was found to increase with decreasing density as expected. Ignition and Growth model parameters were derived that yielded reasonable agreement with the experimental data at both initial densities. The shock sensitivity at the tested densities will be compared to prior work published on other HMX-based formulations. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This work was funded in part by the Joint DoD-DOE Munitions Program.

The dependence of stellar properties on initial cloud density

NASA Astrophysics Data System (ADS)

Jones, Michael O.; Bate, Matthew R.

2018-05-01

We investigate the dependence of stellar properties on the initial mean density of the molecular cloud in which stellar clusters form using radiation hydrodynamical simulations that resolve the opacity limit for fragmentation. We have simulated the formation of three star clusters from the gravitational collapse of molecular clouds whose densities vary by a factor of a hundred. As with previous calculations including radiative feedback, we find that the dependence of the characteristic stellar mass, Mc, on the initial mean density of the cloud, ρ, is weaker than the dependence of the thermal Jeans mass. However, unlike previous calculations, which found no statistically significant variation in the median mass with density, we find a weak dependence approximately of the form Mc∝ρ-1/5. The distributions of properties of multiple systems do not vary significantly between the calculations. We compare our results to the result of observational surveys of star-forming regions, and suggest that the similarities between the properties of our lowest density calculation and the nearby Taurus-Auriga region indicate that the apparent excess of solar-type stars observed may be due to the region's low density.

Method for determining transport critical current densities and flux penetration depth in bulk superconductors

NASA Technical Reports Server (NTRS)

Israelsson, Ulf E. (Inventor); Strayer, Donald M. (Inventor)

1992-01-01

A contact-less method for determining transport critical current density and flux penetration depth in bulk superconductor material. A compressor having a hollow interior and a plunger for selectively reducing the free space area for distribution of the magnetic flux therein are formed of superconductor material. Analytical relationships, based upon the critical state model, Maxwell's equations and geometrical relationships define transport critical current density and flux penetration depth in terms of the initial trapped magnetic flux density and the ratio between initial and final magnetic flux densities whereby data may be reliably determined by means of the simple test apparatus for evaluating the current density and flux penetration depth.

Neutral-depletion-induced axially asymmetric density in a helicon source and imparted thrust

NASA Astrophysics Data System (ADS)

Takahashi, Kazunori; Takao, Yoshinori; Ando, Akira

2016-02-01

The high plasma density downstream of the source is observed to be sustained only for a few hundreds of microsecond at the initial phase of the discharge, when pulsing the radiofrequency power of a helicon plasma thruster. Measured relative density of argon neutrals inside the source implies that the neutrals are significantly depleted there. A position giving a maximum plasma density temporally moves to the upstream side of the source due to the neutral depletion and then the exhausted plasma density significantly decreases. The direct thrust measurement demonstrates that the higher thrust-to-power ratio is obtained by using only the initial phase of the high density plasma, compared with the steady-state operation.

The effect of different initial densities of nematode (Meloidogyne javanica) on the build-up of Pasteuria penetrans population.

PubMed

Darban, Daim Ali; Pathan, Mumtaz Ali; Bhatti, Abdul Ghaffar; Maitelo, Sultan Ahmed

2005-02-01

Pasteuria penetrans will build-up faster where there is a high initial nematode density and can suppress root-knot nematode populations in the roots of tomato plants. The effect of different initial densities of nematode (Meloidogyne javanica) (150, 750, 1500, 3000) and P. penetrans infected females (F1, F3) densities (F0=control and AC=absolute control without nematode or P. penetrans inoculum) on the build-up of Pasteuria population was investigated over four crop cycles. Two major points of interest were highlighted. First, that within a confined soil volume, densities of P. penetrans can increase >100 times within 2 or 3 crop cycles. Second, from a relatively small amount of spore inoculum, infection of the host is very high. There were more infected females in the higher P. penetrans doses. The root growth data confirms the greater number of females in the controls particularly at the higher inoculum densities in the third and fourth crops. P. penetrans generally caused the fresh root weights to be higher than those in the control. P. penetrans has shown greater reduction of egg masses per plant at most densities. The effects of different initial densities of M. javanica and P. penetrans on the development of the pest and parasite populations were monitored. And no attempt was made to return the P. penetrans spores to the pots after each crop so the build-up in actual numbers of infected females and spores under natural conditions may be underestimated.

On the effective Stefan-Boltzmann law and the thermodynamic origin of the initial radiation density in warm inflation

NASA Astrophysics Data System (ADS)

Gim, Yongwan; Kim, Wontae

2018-01-01

In this presentation, we are going to explain the thermodynamic origin of warm inflation scenarios by using the effetive Stefan-Boltzmann law. In the warm inflation scenarios, radiation always exists to avoid the graceful exit problem, for which the radiation energy density should be assumed to be finite at the starting point of the warm inflation. To find out the origin of the non-vanishing initial radiation energy density, we derive an effective Stefan-Boltzmann law by considering the non-vanishing trace of the total energy-momentum tensors. The effective Stefan-Boltzmann law successfully shows where the initial radiation energy density is thermodynamically originated from. And by using the above effective Stefan-Boltzmann law, we also study the cosmological scalar perturbation, and obtain the sufficient radiation energy density in order for GUT baryogenesis at the end of inflation. This proceeding is based on Ref. [1

Taurine: a novel tumor marker for enhanced detection of breast cancer among female patients.

PubMed

El Agouza, I M; Eissa, S S; El Houseini, M M; El-Nashar, Dalia E; Abd El Hameed, O M

2011-09-01

The antioxidant Taurine found to display antineoplastic effect through down regulation of angiogenesis and enhancement of tumor cell apoptosis. It has been found that progressive inhibition of apoptosis and induction of angiogenesis may contribute to tumor initiation, growth and metastasis in the pathogenesis of breast cancer. To correlate taurine level with the levels of some bioomolecules operating in both angiogenesis (VEGF, CD31) and apoptosis (TNF-α and Caspas-3) which could help for breast cancer pronostication and to evaluate a possible role of serum taurine level as an early marker for breast cancer in Egyptian patients. Four groups of a total 85 female candidates were studied in this work. The first group consists of 50 female patients at National Cancer Institute (NCI), Cairo University were diagnosed and undergoing surgery for breast carcinoma. In the second group 10 having benign breast lesions, were included. The third group consists of five cases, with positive family history. Twenty healthy females were also recruited as control. A preoperative blood sample were taken from each patient to measure serum level of VEGF; Taurine; CA15.3 and TNF- α. Sample of fresh tumor and their corresponding safety margins were obtained from the first and second groups, for determination of caspase-3; histopathological examination and immunohistochemical assay of VEGF and CD31. No significant differences in the serum level of CA15.3 between the breast cancer patients, the high risk and the control group. TNF-α (apoptotic biomolecule) level showed a significant difference only between breast cancer group and control group. The VEGF (angiogenic biomarker) showed a highly significant difference between breast cancer patients, the high risk and the control group. Regarding the antioxidant taurine (antiangiogenic biomolecule) serum level in breast cancer group exhibited a value strongly lower than the high risk and control group. Also the correlative ratio between the angiogenic/apoptotic biomarker (VEGF/TNF-α) showed a highly significant difference between the main previous three groups. Same observation were also noticed in the correlation between angiogenic/antiangiogenic (VEGF/taurine) ratio in the same groups. Moreover the enzymatic activities of Casp-3 in the tissue homogenate were statistically higher in adjacent normal tissues than in malignant tissues. The result of immunohistochemical investigation showed a significant increase in the density of intracellular VEGF and microvessel density expressed as CD31 in cancer cases compared to normal adjacent tissue. It is suggested that assessment of taurine level in sera of patients with high risk for breast cancer are of great value in the early diagnosis of malignant changes in the breast.

Bust economics: foragers choose high quality habitats in lean times

PubMed Central

Dickman, Christopher R.

2016-01-01

In environments where food resources are spatially variable and temporarily impoverished, consumers that encounter habitat patches with different food density should focus their foraging initially where food density is highest before they move to patches where food density is lower. Increasing missed opportunity costs should drive individuals progressively to patches with lower food density as resources in the initially high food density patches deplete. To test these expectations, we assessed the foraging decisions of two species of dasyurid marsupials (dunnarts: Sminthopsis hirtipes and S. youngsoni) during a deep drought, or bust period, in the Simpson Desert of central Australia. Dunnarts were allowed access to three patches containing different food densities using an interview chamber experiment. Both species exhibited clear preference for the high density over the lower food density patches as measured in total harvested resources. Similarly, when measuring the proportion of resources harvested within the patches, we observed a marginal preference for patches with initially high densities. Models analyzing behavioral choices at the population level found no differences in behavior between the two species, but models analyzing choices at the individual level uncovered some variation. We conclude that dunnarts can distinguish between habitat patches with different densities of food and preferentially exploit the most valuable. As our observations were made during bust conditions, experiments should be repeated during boom times to assess the foraging economics of dunnarts when environmental resources are high. PMID:26839751

Enhanced inhibition of urinary bladder cancer growth and muscle invasion by allyl isothiocyanate and celecoxib in combination

PubMed Central

Zhang, Yuesheng

2013-01-01

Allyl isothiocyanate (AITC) occurs in cruciferous vegetables that are commonly consumed by humans and has been shown to inhibit urinary bladder cancer growth and progression in previous preclinical studies. However, AITC does not significantly modulate cyclooxygenase-2 (Cox-2), whose oncogenic activity has been well documented in bladder cancer and other cancers. Celecoxib is a selective Cox-2 inhibitor and has been widely used for treatment of several diseases. Celecoxib has also been evaluated in bladder cancer patients, but its efficacy against bladder cancer as a single agent remains unclear. In a syngeneic rat model of orthotopic bladder cancer, treatment of the animals with the combination of AITC and celecoxib at low dose levels (AITC at 1mg/kg and celecoxib at 10mg/kg) led to increased or perhaps synergistic inhibition of bladder cancer growth and muscle invasion, compared with each agent used alone. The combination regime was also more effective than each single agent in inhibiting microvessel formation and stimulating microvessel maturation in the tumor tissues. The anticancer efficacy of the combination regime was associated with depletion of prostaglandin E2, a key downstream signaling molecule of Cox-2, caspase activation and downregulation of vascular endothelial growth factor in the tumor tissues. These data show that AITC and celecoxib complement each other for inhibition of bladder cancer and provide a novel combination approach for potential use for prevention or treatment of human bladder cancer. PMID:23946495

Drag reducing polymers improve tissue perfusion via modification of the RBC traffic in microvessels.

PubMed

Marhefka, J N; Zhao, R; Wu, Z J; Velankar, S S; Antaki, J F; Kameneva, M V

2009-01-01

This paper reports a novel, physiologically significant, microfluidic phenomenon generated by nanomolar concentrations of drag-reducing polymers (DRP) dissolved in flowing blood, which may explain previously demonstrated beneficial effects of DRP on tissue perfusion. In microfluidic systems used in this study, DRP additives were found to significantly modify traffic of red blood cells (RBC) into microchannel branches as well as reduce the near-wall cell-free layer, which normally is found in microvessels with a diameter smaller than 0.3 mm. The reduction in plasma layer size led to attenuation of the so-called "plasma skimming" effect at microchannel bifurcations, increasing the number of RBC entering branches. In vivo, these changes in RBC traffic may facilitate gas transport by increasing the near vessel wall concentration of RBC and capillary hematocrit. In addition, an increase in near-wall viscosity due to the redirection of RBC in this region may potentially decrease vascular resistance as a result of increased wall shear stress, which promotes endothelium mediated vasodilation. These microcirculatory phenomena can explain the previously reported beneficial effects of DRP on hemodynamics in vivo observed in many animal studies. We also report here our finding that DRP additives reduce flow separations at microchannel expansions, deflecting RBC closer to the wall and eliminating the plasma recirculation zone. Although the exact mechanism of the DRP effects on RBC traffic in microchannels is yet to be elucidated, these findings may further DRP progress toward clinical use.

Drag reducing polymers improve tissue perfusion via modification of the RBC traffic in microvessels

PubMed Central

Marhefka, J.N.; Zhao, R.; Wu, Z.; Velankar, S.S.; Antaki, J.F.; Kameneva, M.V.

2011-01-01

This paper reports a novel, physiologically significant, microfluidic phenomenon generated by nanomolar concentrations of drag-reducing polymers (DRP) dissolved in flowing blood, which may explain previously demonstrated beneficial effects of DRP on tissue perfusion. In microfluidic systems used in this study, DRP additives were found to significantly modify traffic of red blood cells (RBC) into microchannel branches as well as reduce the near-wall cell-free layer, which normally is found in microvessels with a diameter smaller than 0.3 mm. The reduction in plasma layer size led to attenuation of the so-called “plasma skimming” effect at microchannel bifurcations, increasing the number of RBC entering branches. In vivo, these changes in RBC traffic may facilitate gas transport by increasing the near vessel wall concentration of RBC and capillary hematocrit. In addition, an increase in near-wall viscosity due to the redirection of RBC in this region may potentially decrease vascular resistance as a result of increased wall shear stress, which promotes endothelium mediated vasodilation. These microcirculatory phenomena may explain the previously reported beneficial effects of DRP on hemodynamics in vivo observed in many animal studies. We also report here our finding that DRP additives reduce flow separations at microchannel expansions, deflecting RBC closer to the wall and eliminating the plasma recirculation zone. Although the exact mechanism of the DRP effects on RBC traffic in microchannels is yet to be elucidated, these findings may further DRP progress toward clinical use. PMID:19721190

Blockade of AT1 Receptors Protects the Blood–Brain Barrier and Improves Cognition in Dahl Salt-Sensitive Hypertensive Rats

PubMed Central

Pelisch, Nicolas; Hosomi, Naohisa; Ueno, Masaki; Nakano, Daisuke; Hitomi, Hirofumi; Mogi, Masaki; Shimada, Kenji; Kobori, Hiroyuki; Horiuchi, Masatsugu; Sakamoto, Haruhiko; Matsumoto, Masayasu; Kohno, Masakazu; Nishiyama, Akira

2011-01-01

BACKGROUND The present study tested the hypothesis that inappropriate activation of the brain renin–angiotensin system (RAS) contributes to the pathogenesis of blood–brain barrier (BBB) disruption and cognitive impairment during development of salt-dependent hypertension. Effects of an angiotensin II (AngII) type-1 receptor blocker (ARB), at a dose that did not reduce blood pressure, were also examined. METHODS Dahl salt-sensitive (DSS) rats at 6 weeks of age were assigned to three groups: low-salt diet (DSS/L; 0.3% NaCl), high-salt diet (DSS/H; 8% NaCl), and high-salt diet treated with ARB, olmesartan at 1 mg/kg. RESULTS DSS/H rats exhibited hypertension, leakage from brain microvessels in the hippocampus, and impaired cognitive functions, which were associated with increased brain AngII levels, as well as decreased mRNA levels of tight junctions (TJs) and collagen-IV in the hippocampus. In DSS/H rats, olmesartan treatment, at a dose that did not alter blood pressure, restored the cognitive decline, and ameliorated leakage from brain microvessels. Olmesartan also decreased brain AngII levels and restored mRNA expression of TJs and collagen-IV in DSS/H rats. CONCLUSIONS These results suggest that during development of salt-dependent hypertension, activation of the brain RAS contributes to BBB disruption and cognitive impairment. Treatment with an ARB could elicit neuroprotective effects in cognitive disorders by preventing BBB permeability, which is independent of blood pressure changes. PMID:21164491

Ultrafast Synthetic Transmit Aperture Imaging Using Hadamard-Encoded Virtual Sources With Overlapping Sub-Apertures.

PubMed

Ping Gong; Pengfei Song; Shigao Chen

2017-06-01

The development of ultrafast ultrasound imaging offers great opportunities to improve imaging technologies, such as shear wave elastography and ultrafast Doppler imaging. In ultrafast imaging, there are tradeoffs among image signal-to-noise ratio (SNR), resolution, and post-compounded frame rate. Various approaches have been proposed to solve this tradeoff, such as multiplane wave imaging or the attempts of implementing synthetic transmit aperture imaging. In this paper, we propose an ultrafast synthetic transmit aperture (USTA) imaging technique using Hadamard-encoded virtual sources with overlapping sub-apertures to enhance both image SNR and resolution without sacrificing frame rate. This method includes three steps: 1) create virtual sources using sub-apertures; 2) encode virtual sources using Hadamard matrix; and 3) add short time intervals (a few microseconds) between transmissions of different virtual sources to allow overlapping sub-apertures. The USTA was tested experimentally with a point target, a B-mode phantom, and in vivo human kidney micro-vessel imaging. Compared with standard coherent diverging wave compounding with the same frame rate, improvements on image SNR, lateral resolution (+33%, with B-mode phantom imaging), and contrast ratio (+3.8 dB, with in vivo human kidney micro-vessel imaging) have been achieved. The f-number of virtual sources, the number of virtual sources used, and the number of elements used in each sub-aperture can be flexibly adjusted to enhance resolution and SNR. This allows very flexible optimization of USTA for different applications.

In vitro and ex vivo angiogenic effects of roxarsone on rat endothelial cells.

PubMed

Zhu, Jiaqiao; Cui, Weibo; Liu, Xue; Ying, Jun; Hu, Chengyun; Zhang, Yumei

2013-11-25

Roxarsone, a feed additive, is being used worldwide to promote animal growth. However, the potential effect of roxarsone on angiogenesis has not been extensively characterized. We examined the ability of roxarsone to promote angiogenesis of rat endothelial cells in vitro and from rat aorta rings ex vivo. Endothelial cells from rats were exposed to 0.01-10.00μM roxarsone, 5ng/mL vascular endothelial growth factor (VEGF) as a positive control or phosphate buffer saline (PBS) as a negative control. Cell proliferation was measured by MTT assay, and the content of VEGF in supernatants was measured by enzyme-linked immunosorbent assay and Western blotting. A Matrigel-induced tube formation assay was used to evaluate the effects of roxarsone on endothelial cells. Additionally, the total number and length of microvessels sprouted from rat aortic rings were measured for ex vivo investigation of angiogenesis. Results showed that the cell viability and total number and length of capillary-like tube formations after roxarsone treatment was significantly higher than that of negative (P<0.05), with a maximum effect at 1.00μM exposure. Furthermore, the number of microvessels sprouted from aortic rings treated for 4h with 0.1-10.0μM roxarsone was significantly higher than that of PBS treatment, with a peak value of 1.0μM. These results further demonstrate the potential of roxarsone to promote angiogenesis in vitro and ex vivo. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

DCEUS-based focal parametric perfusion imaging of microvessel with single-pixel resolution and high contrast.

PubMed

Wang, Diya; Xiao, Mengnan; Hu, Hong; Zhang, Yu; Su, Zhe; Xu, Shanshan; Zong, Yujin; Wan, Mingxi

2018-03-01

This study aimed to develop a focal microvascular contrast-enhanced ultrasonic parametric perfusion imaging (PPI) scheme to overcome the tradeoff between the resolution, contrast, and accuracy of focal PPI in the tumor. Its resolution was limited by the low signal-to-clutter ratio (SCR) of time-intensity-curves (TICs) induced by multiple limitations, which deteriorated the accuracy and contrast of focal PPI. The scheme was verified by the in-vivo perfusion experiments. Single-pixel TICs were first extracted to ensure PPI with the highest resolution. The SCR of focal TICs in the tumor was improved using respiratory motion compensation combined with detrended fluctuation analysis. The entire and focal PPIs of six perfusion parameters were then accurately created after filtrating the valid TICs and targeted perfusion parameters. Compared with those of the conventional PPIs, the axial and lateral resolutions of focal PPIs were improved by 30.29% (p < .05) and 32.77% (p < .05), respectively; the average contrast and accuracy evaluated by SCR improved by 7.24 ± 4.90 dB (p < .05) and 5.18 ± 1.28 dB (p < .05), respectively. The edge, morphostructure, inhomogeneous hyper-enhanced distribution, and ring-like perfusion features in intratumoral microvessel were accurately distinguished and highlighted by the focal PPIs. The developed focal PPI can assist clinicians in making confirmed diagnoses and in providing appropriate therapeutic strategies for liver tumor. Copyright © 2017 Elsevier B.V. All rights reserved.