Awareness of technology-induced errors and processes for identifying and preventing such errors.

PubMed

Bellwood, Paule; Borycki, Elizabeth M; Kushniruk, Andre W

2015-01-01

There is a need to determine if organizations working with health information technology are aware of technology-induced errors and how they are addressing and preventing them. The purpose of this study was to: a) determine the degree of technology-induced error awareness in various Canadian healthcare organizations, and b) identify those processes and procedures that are currently in place to help address, manage, and prevent technology-induced errors. We identified a lack of technology-induced error awareness among participants. Participants identified there was a lack of well-defined procedures in place for reporting technology-induced errors, addressing them when they arise, and preventing them.

Osteocyte-derived RANKL is a critical mediator of the increased bone resorption caused by dietary calcium deficiency

PubMed Central

Xiong, Jinhu; Piemontese, Marilina; Thostenson, Jeff D.; Weinstein, Robert S.; Manolagas, Stavros C.; O’Brien, Charles A.

2014-01-01

Parathyroid hormone (PTH) excess stimulates bone resorption. This effect is associated with increased expression of the osteoclastogenic cytokine receptor activator of nuclear factor кB ligand (RANKL) in bone. However, several different cell types, including bone marrow stromal cells, osteocytes, and T lymphocytes, express both RANKL and the PTH receptor and it is unclear whether RANKL expression by any of these cell types is required for PTH-induced bone loss. Here we have used mice lacking the RANKL gene in osteocytes to determine whether RANKL produced by this cell type is required for the bone loss caused by secondary hyperparathyroidism induced by dietary calcium deficiency in adult mice. Thirty days of dietary calcium deficiency caused bone loss in control mice, but this effect was blunted in mice lacking RANKL in osteocytes. The increase in RANKL expression in bone and the increase in osteoclast number caused by dietary calcium deficiency were also blunted in mice lacking RANKL in osteocytes. These results demonstrate that RANKL produced by osteocytes contributes to the increased bone resorption and the bone loss caused by secondary hyperparathyroidism, strengthening the evidence that osteocytes are an important target cell for hormonal control of bone remodeling. PMID:24933342

A mutation that eliminates bundle sheath extensions reduces leaf hydraulic conductance, stomatal conductance and assimilation rates in tomato (Solanum lycopersicum).

PubMed

Zsögön, Agustin; Negrini, Ana Clarissa Alves; Peres, Lázaro Eustáquio Pereira; Nguyen, Hoa Thi; Ball, Marilyn C

2015-01-01

Bundle sheath extensions (BSEs) are key features of leaf structure whose distribution differs among species and ecosystems. The genetic control of BSE development is unknown, so BSE physiological function has not yet been studied through mutant analysis. We screened a population of ethyl methanesulfonate (EMS)-induced mutants in the genetic background of the tomato (Solanum lycopersicum) model Micro-Tom and found a mutant lacking BSEs. The leaf phenotype of the mutant strongly resembled the tomato mutant obscuravenosa (obv). We confirmed that obv lacks BSEs and that it is not allelic to our induced mutant, which we named obv-2. Leaves lacking BSEs had lower leaf hydraulic conductance and operated with lower stomatal conductance and correspondingly lower assimilation rates than wild-type leaves. This lower level of function occurred despite similarities in vein density, midvein vessel diameter and number, stomatal density, and leaf area between wild-type and mutant leaves, the implication being that the lack of BSEs hindered water dispersal within mutant leaves. Our results comparing near-isogenic lines within a single species confirm the hypothesised role of BSEs in leaf hydraulic function. They further pave the way for a genetic model-based analysis of a common leaf structure with deep ecological consequences. © 2014 The Authors New Phytologist © 2014 New Phytologist Trust.

Sex differences in the acute locomotor response to methamphetamine in BALB/c mice.

PubMed

Ohia-Nwoko, Odochi; Haile, Colin N; Kosten, Therese A

2017-06-01

Women use methamphetamine more frequently than men and are more vulnerable to its negative psychological effects. Rodent models have been an essential tool for evaluating the sex-dependent effects of psychostimulants; however, evidence of sex differences in the behavioral responses to methamphetamine in mice is lacking. In the present study, we investigated acute methamphetamine-induced (1mg/kg and 4mg/kg) locomotor activation in female and male BALB/c mice. We also evaluated whether basal locomotor activity was associated with the methamphetamine-induced locomotor response. The results indicated that female BALB/c mice displayed enhanced methamphetamine-induced locomotor activity compared to males, while basal locomotor activity was positively correlated with methamphetamine-induced activity in males, but not females. This study is the first to show sex-dependent locomotor effects of methamphetamine in BALB/c mice. Our observations emphasize the importance of considering sex when assessing behavioral responses to methamphetamine. Copyright © 2017 Elsevier B.V. All rights reserved.

Alterations in voltage-sensing of the mitochondrial permeability transition pore in ANT1-deficient cells

PubMed Central

Doczi, Judit; Torocsik, Beata; Echaniz-Laguna, Andoni; Mousson de Camaret, Bénédicte; Starkov, Anatoly; Starkova, Natalia; Gál, Aniko; Molnár, Mária J; Kawamata, Hibiki; Manfredi, Giovanni; Adam-Vizi, Vera; Chinopoulos, Christos

2016-01-01

The probability of mitochondrial permeability transition (mPT) pore opening is inversely related to the magnitude of the proton electrochemical gradient. The module conferring sensitivity of the pore to this gradient has not been identified. We investigated mPT’s voltage-sensing properties elicited by calcimycin or H2O2 in human fibroblasts exhibiting partial or complete lack of ANT1 and in C2C12 myotubes with knocked-down ANT1 expression. mPT onset was assessed by measuring in situ mitochondrial volume using the ‘thinness ratio’ and the ‘cobalt-calcein’ technique. De-energization hastened calcimycin-induced swelling in control and partially-expressing ANT1 fibroblasts, but not in cells lacking ANT1, despite greater losses of mitochondrial membrane potential. Matrix Ca2+ levels measured by X-rhod-1 or mitochondrially-targeted ratiometric biosensor 4mtD3cpv, or ADP-ATP exchange rates did not differ among cell types. ANT1-null fibroblasts were also resistant to H2O2-induced mitochondrial swelling. Permeabilized C2C12 myotubes with knocked-down ANT1 exhibited higher calcium uptake capacity and voltage-thresholds of mPT opening inferred from cytochrome c release, but intact cells showed no differences in calcimycin-induced onset of mPT, irrespective of energization and ANT1 expression, albeit the number of cells undergoing mPT increased less significantly upon chemically-induced hypoxia than control cells. We conclude that ANT1 confers sensitivity of the pore to the electrochemical gradient. PMID:27221760

In Silico Investigations of the Anti-Catabolic Effects of Pamidronate and Denosumab on Multiple Myeloma-Induced Bone Disease

PubMed Central

Wang, Yan; Lin, Bo

2012-01-01

It is unclear whether the new anti-catabolic agent denosumab represents a viable alternative to the widely used anti-catabolic agent pamidronate in the treatment of Multiple Myeloma (MM)-induced bone disease. This lack of clarity primarily stems from the lack of sufficient clinical investigations, which are costly and time consuming. However, in silico investigations require less time and expense, suggesting that they may be a useful complement to traditional clinical investigations. In this paper, we aim to (i) develop integrated computational models that are suitable for investigating the effects of pamidronate and denosumab on MM-induced bone disease and (ii) evaluate the responses to pamidronate and denosumab treatments using these integrated models. To achieve these goals, pharmacokinetic models of pamidronate and denosumab are first developed and then calibrated and validated using different clinical datasets. Next, the integrated computational models are developed by incorporating the simulated transient concentrations of pamidronate and denosumab and simulations of their actions on the MM-bone compartment into the previously proposed MM-bone model. These integrated models are further calibrated and validated by different clinical datasets so that they are suitable to be applied to investigate the responses to the pamidronate and denosumab treatments. Finally, these responses are evaluated by quantifying the bone volume, bone turnover, and MM-cell density. This evaluation identifies four denosumab regimes that potentially produce an overall improved bone-related response compared with the recommended pamidronate regime. This in silico investigation supports the idea that denosumab represents an appropriate alternative to pamidronate in the treatment of MM-induced bone disease. PMID:23028650

Lymphotoxin Regulates Commensal Responses to Enable Diet-Induced Obesity

PubMed Central

Upadhyay, Vaibhav; Poroyko, Valeriy; Kim, Tae-jin; Devkota, Suzanne; Fu, Sherry; Liu, Donald; Tumanov, Alexei V.; Koroleva, Ekaterina P.; Deng, Liufu; Nagler, Cathryn; Chang, Eugene; Tang, Hong; Fu, Yang-Xin

2013-01-01

The microbiota plays a critical, weight-promoting role in diet-induced obesity (DIO), but the pathways that cause the microbiota to induce weight gain are unknown. We report that mice deficient in lymphotoxin (LT), a key molecule in gut immunity, were resistant to DIO. Ltbr−/− mice differed in microbial community composition compared to their heterozygous littermates, including an overgrowth of segmented filamentous bacteria (SFB). Furthermore, cecal transplantation conferred leanness to germ-free recipients. Housing Ltbr−/− mice with their obese siblings rescued weight gain, demonstrating the communicability of the obese phenotype. Ltbr−/− animals lacked interleukin 23 (IL-23) and IL-22 that can regulate SFB. Mice deficient in these pathways also resisted DIO, demonstrating that intact mucosal immunity guides diet-induced changes to the microbiota to enable obesity. PMID:22922363

Comparative Assessment of Induced Immune Responses Following Intramuscular Immunization with Fusion and Cocktail of LeIF, LACK and TSA Genes Against Cutaneous Leishmaniasis in BALB/c Mice.

PubMed

Maspi, Nahid; Ghaffarifar, Fatemeh; Sharifi, Zohreh; Dalimi, Abdolhossein; Dayer, Mohammad Saaid

2018-02-01

In the present study, we evaluated induced immune responses following DNA vaccine containing cocktail or fusion of LeIF, LACK and TSA genes or each gene alone. Mice were injected with 100 µg of each plasmid containing the gene of insert, plasmid DNA alone as the first control group or phosphate buffer saline as the second control group. Then, cellular and humoral responses, lesion size were measured for all groups. All vaccinated mice induced Th1 immune responses against Leishmania characterized by higher IFN-γ and IgG2a levels compared with control groups (p < 0.05). In addition, IFN-γ levels increased in groups immunized with fusion and cocktail vaccines in comparison with LACK (p < 0.001) and LeIF (p < 0.01) groups after challenge. In addition, fusion and cocktail groups produced higher IgG2a values than groups vaccinated with a gene alone (p < 0.05). Lesion progression delayed for all immunized groups compared with control groups from 5th week post-infection (p < 0.05). Mean lesion size decreased in immunized mice with fusion DNA than three groups vaccinated with one gene alone (p < 0.05). While, lesion size decreased significantly in cocktail recipient group than LeIF recipient group (p < 0.05). There was no difference in lesion size between fusion and cocktail groups. Overall, immunized mice with cocktail and fusion vaccines showed stronger Th1 response by production of higher IFN-γ and IgG2a and showed smaller mean lesion size. Therefore, use of multiple antigens can improve induced immune responses by DNA vaccination.

Visual Illusions and the Control of Ball Placement in Goal-Directed Hitting

ERIC Educational Resources Information Center

Caljouw, Simone R.; Van der Kamp, John; Savelsbergh, Geert J. P.

2010-01-01

When hitting, kicking, or throwing balls at targets, online control in the target area is impossible. We assumed this lack of late corrections in the target area would induce an effect of a single-winged Muller-Lyer illusion on ball placement. After extensive practice in hitting balls to different landing locations, participants (N = 9) had to hit…

Drug-induced cholestasis: mechanisms, models, and markers.

PubMed

Chatterjee, Sagnik; Annaert, Pieter

2018-04-27

Drug-induced cholestasis is a risk factor in progression of drug candidates, and poses serious health hazard if not detected before going into human. Intrahepatic accumulation of bile acids (BAs) represents a characteristic phenomenon associated with drug-induced cholestasis. The major challenges in obtaining a complete understanding of drug-induced cholestasis lies in the complexity of BA-mediated toxicity mechanisms and the impact of bile acids at different 'targets' such as transporters, enzymes and nuclear receptors. At the same time, it is not trivial to have a relevant in vitro system that recapitulates these features. In addition, lack of sensitive and early preclinical biomarkers, relevant to the clinical situation, complicates proper detection of drug-induced cholestasis. Significant overlap in biomarker signatures between different mechanisms of drug-induced liver injury (DILI) precludes identification of specific mechanisms. Over the last decade the knowledge gaps in drug-induced cholestasis are closing due to growing mechanistic understanding of BA-mediated toxicity at (patho)physiologically relevant BA concentrations. Significant progress has been made in the mechanistic understanding of drug-induced cholestasis and associated toxicity, biomarkers and susceptibility factors. In addition, novel in vitro models are evolving which provide a holistic understanding of processes underlying drug-induced cholestasis. This review summarizes the challenges and recent understandings about drug-induced cholestasis with a potential path forward. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Post abortion syndrome?

PubMed

1987-12-01

There is general agreement that uncertainty persists regarding the psychological sequelae of abortion. Inconsistencies of interpretation stem from a lack of consensus about the symptoms, severity, and duration of mental disorder. In addition, opinions differ based on individual case studies and there is no national reporting system or adequate follow up system. Frequently, reviews combine studies conducted prior to and after the 1973 Supreme Court decision, mix elective abortion with those induced for medical reasons, or fail to distinguish between abortions performed early or late in gestation. The literature reveals methodological problems, a lack of controls, and sampling inadequacies. A review of the available literature and the files of "Abortion Research Notes" suggests that women at particular risk for postabortion stress reactions are those who terminate an originally wanted pregnancy, are strongly ambivalent, come very late in their pregnancy, or lack the support of significant others.

Clinical Isolates of Mycobacterium tuberculosis Differ in Their Ability to Induce Respiratory Burst and Apoptosis in Neutrophils as a Possible Mechanism of Immune Escape

PubMed Central

Romero, María M.; Balboa, Luciana; Basile, Juan I.; López, Beatriz; Ritacco, Viviana; de la Barrera, Silvia S.; Sasiain, María C.; Barrera, Lucía; Alemán, Mercedes

2012-01-01

Tuberculosis pathogenesis was earlier thought to be mainly related to the host but now it appears to be clear that bacterial factors are also involved. Genetic variability of Mycobacterium tuberculosis (Mtb) could be slight but it may lead to sharp phenotypic differences. We have previously reported that nonopsonized Mtb H37Rv induce apoptosis of polymorphonuclear neutrophils (PMNs) by a mechanism that involves the p38 pathway. Here we evaluated the capability to induce PMN apoptosis of two prevalent Mtb lineages in Argentina, the Latin America and Mediterranean (LAM), and Haarlem, using the H37Rv as a reference strain. Results showed that LAM strains strongly induced apoptosis of PMN which correlated with the induction of reactive oxygen species (ROS) production and p38 activation. Interestingly, the highly prosperous multidrug-resistant M strain, belonging to the Haarlem lineage, lacked the ability to activate and to induce PMN apoptosis as a consequence of (1) a weak ROS production and (2) the contribution of antiapoptotic mechanisms mediated at least by ERK. Although with less skill, M is able to enter the PMN so that phenotypic differences could lead PMN to be a reservoir allowing some pathogens to prevail and persist over other strains in the community. PMID:22778761

Investigation of sunlight-induced deterioration of aroma of pummelo (Citrus maxima) essential oil.

PubMed

Sun, Hao; Ni, Hui; Yang, Yuanfan; Wu, Ling; Cai, Hui-nong; Xiao, An-feng; Chen, Feng

2014-12-10

Deterioration of aromas of pummelo essential oil (EO) induced by sunlight was compared to those induced by heat and oxygen exposure using the techniques of sensory evaluation and GC-MS analysis. The sunlight-exposed EO was found to possess an oily off-flavor odor, which was significantly different from its counterparts induced by oxygen and heat. The strong oily note of the sunlight-exposed EO was attributed to the existence of linalool oxides and limonene oxides, as well as the lack of neral and geranial, for which UV sunlight was revealed to be the critical contributor causing the chemical reactions for the aroma changes. The results demonstrated that UV sunlight could significantly affect the aroma of the pummelo EO, providing valuable information that will benefit the production and storage of EO-based aromatic products.

Down-Regulation of p53 by Double-Stranded RNA Modulates the Antiviral Response

PubMed Central

Marques, Joao T.; Rebouillat, Dominique; Ramana, Chilakamarti V.; Murakami, Junko; Hill, Jason E.; Gudkov, Andrei; Silverman, Robert H.; Stark, George R.; Williams, Bryan R. G.

2005-01-01

p53 has been well characterized as a tumor suppressor gene, but its role in antiviral defense remains unclear. A recent report has demonstrated that p53 can be induced by interferons and is activated after vesicular stomatitis virus (VSV) infection. We observed that different nononcogenic viruses, including encephalomyocarditis virus (EMCV) and human parainfluenza virus type 3 (HPIV3), induced down-regulation of p53 in infected cells. Double-stranded RNA (dsRNA) and a mutant vaccinia virus lacking the dsRNA binding protein E3L can also induce this effect, indicating that dsRNA formed during viral infection is likely the trigger for down-regulation of p53. The mechanism of down-regulation of p53 by dsRNA relies on translation inhibition mediated by the PKR and RNase L pathways. In the absence of p53, the replication of both EMCV and HPIV3 was retarded, whereas, conversely, VSV replication was enhanced. Cell cycle analysis indicated that wild-type (WT) but not p53 knockout (KO) fibroblasts undergo an early-G1 arrest following dsRNA treatment. Moreover, in WT cells the onset of dsRNA-induced apoptosis begins after p53 levels are down-regulated, whereas p53 KO cells, which lack the early-G1 arrest, rapidly undergo apoptosis. Hence, our data suggest that the down-regulation of p53 facilitates apoptosis, thereby limiting viral replication. PMID:16103161

Hyperbaric oxygen therapy and preconditioning for ischemic and hemorrhagic stroke.

PubMed

Hu, Sheng-Li; Feng, Hua; Xi, Guo-Hua

2016-01-01

To date, the therapeutic methods for ischemic and hemorrhagic stroke are still limited. The lack of oxygen supply is critical for brain injury following stroke. Hyperbaric oxygen (HBO), an approach through a process in which patients breathe in 100% pure oxygen at over 101 kPa, has been shown to facilitate oxygen delivery and increase oxygen supply. Hence, HBO possesses the potentials to produce beneficial effects on stroke. Actually, accumulated basic and clinical evidences have demonstrated that HBO therapy and preconditioning could induce neuroprotective functions via different mechanisms. Nevertheless, the lack of clinical translational study limits the application of HBO. More translational studies and clinical trials are needed in the future to develop effective HBO protocols.

Lessons learned using different mouse models during space radiation-induced lung tumorigenesis experiments

NASA Astrophysics Data System (ADS)

Wang, Jian; Zhang, Xiangming; Wang, Ping; Wang, Xiang; Farris, Alton B.; Wang, Ya

2016-06-01

Unlike terrestrial ionizing radiation, space radiation, especially galactic cosmic rays (GCR), contains high energy charged (HZE) particles with high linear energy transfer (LET). Due to a lack of epidemiologic data for high-LET radiation exposure, it is highly uncertain how high the carcinogenesis risk is for astronauts following exposure to space radiation during space missions. Therefore, using mouse models is necessary to evaluate the risk of space radiation-induced tumorigenesis; however, which mouse model is better for these studies remains uncertain. Since lung tumorigenesis is the leading cause of cancer death among both men and women, and low-LET radiation exposure increases human lung carcinogenesis, evaluating space radiation-induced lung tumorigenesis is critical to enable safe Mars missions. Here, by comparing lung tumorigenesis obtained from different mouse strains, as well as miR-21 in lung tissue/tumors and serum, we believe that wild type mice with a low spontaneous tumorigenesis background are ideal for evaluating the risk of space radiation-induced lung tumorigenesis, and circulating miR-21 from such mice model might be used as a biomarker for predicting the risk.

Associations between personality traits and CCK-4-induced panic attacks in healthy volunteers.

PubMed

Tõru, Innar; Aluoja, Anu; Võhma, Ulle; Raag, Mait; Vasar, Veiko; Maron, Eduard; Shlik, Jakov

2010-07-30

In this study we examined how personality disposition may affect the response to cholecystokinin tetrapeptide (CCK-4; 50 microg) challenge in healthy volunteers (n=105). Personality traits were assessed with the Swedish universities Scales of Personality (SSP). Statistical methods employed were correlation analysis and logistic regression. The results showed that the occurrence of CCK-4-induced panic attacks was best predicted by baseline diastolic blood pressure, preceding anxiety and SSP-defined traits of lack of assertiveness, detachment, embitterment and verbal aggression. Significant interactions were noted between the above mentioned variables, modifying their individual effects. For different subsets of CCK-4-induced symptoms, the traits of physical aggression, irritability, somatic anxiety and stress susceptibility also appeared related to panic manifestations. These findings suggest that some personality traits and their interactions may influence vulnerability to CCK-4-induced panic attacks in healthy volunteers. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Antinociceptive and anti-inflammatory activities of a pomegranate (Punica granatum L.) extract rich in ellagitannins.

PubMed

González-Trujano, María Eva; Pellicer, Francisco; Mena, Pedro; Moreno, Diego A; García-Viguera, Cristina

2015-01-01

Pomegranate (Punica granatum L.) has been used for centuries for the treatment of inflammatory diseases. However, there is a lack of comprehensive information focused on the properties of a certain pomegranate (poly)phenolic profile to cure pain and gastric injury induced by anti-inflammatory drugs. This study investigated the systemic effects of different doses of a HPLC-characterized pomegranate extract on the formalin-induced nociceptive behavior in mice. The effect of the extract against gastric injury caused by non-steroidal anti-inflammatory drugs and ethanol was also assessed. Pomegranate reduced nociception in both phases of the formalin test, suggesting central and peripheral activities to inhibit nociception. Indomethacin-induced gastric injury was not produced in the presence of pomegranate, which also protected against ethanol-induced gastric lesions. The present results reinforce the benefits of pomegranate (poly)phenolics in the treatment of pain as well as their anti-inflammatory properties.

Island phytophagy: explaining the remarkable diversity of plant-feeding insects

PubMed Central

Joy, Jeffrey B.; Crespi, Bernard J.

2012-01-01

Plant-feeding insects have undergone unparalleled diversification among different plant taxa, yet explanations for variation in their diversity lack a quantitative, predictive framework. Island biogeographic theory has been applied to spatially discrete habitats but not to habitats, such as host plants, separated by genetic distance. We show that relationships between the diversity of gall-inducing flies and their host plants meet several fundamental predictions from island biogeographic theory. First, plant-taxon genetic distinctiveness, an integrator for long-term evolutionary history of plant lineages, is a significant predictor of variance in the diversity of gall-inducing flies among host-plant taxa. Second, range size and structural complexity also explain significant proportions of the variance in diversity of gall-inducing flies among different host-plant taxa. Third, as with other island systems, plant-lineage age does not predict species diversity. Island biogeographic theory, applied to habitats defined by genetic distance, provides a novel, comprehensive framework for analysing and explaining the diversity of plant-feeding insects and other host-specific taxa. PMID:22553094

Island phytophagy: explaining the remarkable diversity of plant-feeding insects.

PubMed

Joy, Jeffrey B; Crespi, Bernard J

2012-08-22

Plant-feeding insects have undergone unparalleled diversification among different plant taxa, yet explanations for variation in their diversity lack a quantitative, predictive framework. Island biogeographic theory has been applied to spatially discrete habitats but not to habitats, such as host plants, separated by genetic distance. We show that relationships between the diversity of gall-inducing flies and their host plants meet several fundamental predictions from island biogeographic theory. First, plant-taxon genetic distinctiveness, an integrator for long-term evolutionary history of plant lineages, is a significant predictor of variance in the diversity of gall-inducing flies among host-plant taxa. Second, range size and structural complexity also explain significant proportions of the variance in diversity of gall-inducing flies among different host-plant taxa. Third, as with other island systems, plant-lineage age does not predict species diversity. Island biogeographic theory, applied to habitats defined by genetic distance, provides a novel, comprehensive framework for analysing and explaining the diversity of plant-feeding insects and other host-specific taxa.

A Review of Pinealectomy-Induced Melatonin-Deficient Animal Models for the Study of Etiopathogenesis of Adolescent Idiopathic Scoliosis

PubMed Central

Wai, Man Gene Chi; Jun, Wang William Wei; Yee, Yim Annie Po; Ho, Wong Jack; Bun, Ng Tzi; Ping, Lam Tsz; Man, Lee Simon Kwong; Wah, Ng Bobby Kin; Chiu, Wang Chi; Yong, Qiu; Yiu, Cheng Jack Chun

2014-01-01

Adolescent idiopathic scoliosis (AIS) is a common orthopedic disorder of unknown etiology and pathogenesis. Melatonin and melatonin pathway dysfunction has been widely suspected to play an important role in the pathogenesis. Many different types of animal models have been developed to induce experimental scoliosis mimicking the pathoanatomical features of idiopathic scoliosis in human. The scoliosis deformity was believed to be induced by pinealectomy and mediated through the resulting melatonin-deficiency. However, the lack of upright mechanical spinal loading and inherent rotational instability of the curvature render the similarity of these models to the human counterparts questionable. Different concerns have been raised challenging the scientific validity and limitations of each model. The objectives of this review follow the logical need to re-examine and compare the relevance and appropriateness of each of the animal models that have been used for studying the etiopathogenesis of adolescent idiopathic scoliosis in human in the past 15 to 20 years. PMID:25238413

Tip-induced domain growth on the non-polar cuts of lithium niobate single-crystals

DOE PAGES

Alikin, Denis O.; Ievlev, Anton; Turigin, Anton P.; ...

2015-05-05

Currently ferroelectric materials with designed domain structures are considered as a perspective material for new generation of photonic, data storage and data processing devices. Application of external electric field is the most convenient way of the domain structure formation. Lots of papers are devoted to investigation of the domain kinetics on polar surface of crystals while the forward growth remains one of the most mysterious stages due to lack of experimental methods allowing to study it. Here we performed tip-induced polarization reversal on X- and Y-non-polar cuts in single-crystal of congruent lithium niobate allows us to study the forward growthmore » with high spatial resolution. The revealed difference in the shape and length of domains induced on X- and Y-cuts is beyond previously developed theoretical approaches used for the theoretical consideration of the domains growth at non-polar ferroelectric surfaces. Lastly, to explain experimental results we used kinetic approach with anisotropy of screening efficiency along different crystallographic directions.« less

Mechanical Insight into Resistance of Betaine to Urea-Induced Protein Denaturation.

PubMed

Chen, Jiantao; Gong, Xiangjun; Zeng, Chaoxi; Wang, Yonghua; Zhang, Guangzhao

2016-12-08

It is known that urea can induce protein denaturation that can be inhibited by osmolytes. Yet, experimental explorations on this mechanism at the molecular level are still lacking. We have investigated the resistance of betaine to the urea-induced denaturation of lysozyme in aqueous solutions using low-field NMR. Our study demonstrates that urea molecules directly interact with lysozyme, leading to denaturation. However, betaine molecules interacting with urea more strongly than lysozyme can pull the bound urea molecules from lysozyme so that the protein is protected from denaturation. The number of urea molecules bound to a betaine molecule is given under different conditions. Proton NMR spectroscopy ( 1 H-NMR) and Fourier transform infrared spectroscopy reveal that the interaction between betaine and urea is through hydrogen bonding.

Python erythrocytes are resistant to α-hemolysin from Escherichia coli.

PubMed

Larsen, Casper K; Skals, Marianne; Wang, Tobias; Cheema, Muhammad U; Leipziger, Jens; Praetorius, Helle A

2011-12-01

α-Hemolysin (HlyA) from Escherichia coli lyses mammalian erythrocytes by creating nonselective cation pores in the membrane. Pore insertion triggers ATP release and subsequent P2X receptor and pannexin channel activation. Blockage of either P2X receptors or pannexin channels reduces HlyA-induced hemolysis. We found that erythrocytes from Python regius and Python molurus are remarkably resistant to HlyA-induced hemolysis compared to human and Trachemys scripta erythrocytes. HlyA concentrations that induced maximal hemolysis of human erythrocytes did not affect python erythrocytes, but increasing the HlyA concentration 40-fold did induce hemolysis. Python erythrocytes were more resistant to osmotic stress than human erythrocytes, but osmotic stress tolerance per se did not confer HlyA resistance. Erythrocytes from T. scripta, which showed higher osmotic resistance than python erythrocytes, were as susceptible to HlyA as human erythrocytes. Therefore, we tested whether python erythrocytes lack the purinergic signalling known to amplify HlyA-induced hemolysis in human erythrocytes. P. regius erythrocytes increased intracellular Ca²⁺ concentration and reduced cell volume when exposed to 3 mM ATP, indicating the presence of a P2X₇-like receptor. In addition, scavenging extracellular ATP or blocking P2 receptors or pannexin channels reduced the HlyA-induced hemolysis. We tested whether the low HlyA sensitivity resulted from low affinity of HlyA to the python erythrocyte membrane. We found comparable incorporation of HlyA into human and python erythrocyte membranes. Taken together, the remarkable HlyA resistance of python erythrocytes was not explained by increased osmotic resistance, lack of purinergic hemolysis amplification, or differences in HlyA affinity.

Perception of sweet taste is important for voluntary alcohol consumption in mice.

PubMed

Blednov, Y A; Walker, D; Martinez, M; Levine, M; Damak, S; Margolskee, R F

2008-02-01

To directly evaluate the association between taste perception and alcohol intake, we used three different mutant mice, each lacking a gene expressed in taste buds and critical to taste transduction: alpha-gustducin (Gnat3), Tas1r3 or Trpm5. Null mutant mice lacking any of these three genes showed lower preference score for alcohol and consumed less alcohol in a two-bottle choice test, as compared with wild-type littermates. These null mice also showed lower preference score for saccharin solutions than did wild-type littermates. In contrast, avoidance of quinine solutions was less in Gnat3 or Trpm5 knockout mice than in wild-type mice, whereas Tas1r3 null mice were not different from wild type in their response to quinine solutions. There were no differences in null vs. wild-type mice in their consumption of sodium chloride solutions. To determine the cause for reduction of ethanol intake, we studied other ethanol-induced behaviors known to be related to alcohol consumption. There were no differences between null and wild-type mice in ethanol-induced loss of righting reflex, severity of acute ethanol withdrawal or conditioned place preference for ethanol. Weaker conditioned taste aversion (CTA) to alcohol in null mice may have been caused by weaker rewarding value of the conditioned stimulus (saccharin). When saccharin was replaced by sodium chloride, no differences in CTA to alcohol between knockout and wild-type mice were seen. Thus, deletion of any one of three different genes involved in detection of sweet taste leads to a substantial reduction of alcohol intake without any changes in pharmacological actions of ethanol.

PERCEPTION OF SWEET TASTE IS IMPORTANT FOR VOLUNTARY ALCOHOL CONSUMPTION IN MICE

PubMed Central

Blednov, Y.A.; Walker, D.; Martinez, M.; Levine, M.; Damak, S.; Margolskee, R.F.

2012-01-01

To directly evaluate the association between taste perception and alcohol intake, we used three different mutant mice, each lacking a gene expressed in taste buds and critical to taste transduction: α-gustducin (Gnat3), Tas1r3 or Trpm5. Null mutant mice lacking any of these three genes showed lower preference score for alcohol and consumed less alcohol in a two-bottle choice test, as compared with wild-type littermates. These null mice also showed lower preference score for saccharin solutions than did wild-type littermates. In contrast, avoidance of quinine solutions was less in Gnat3 or Trpm5 knockout mice than in wild type mice, whereas Tas1r3 null mice were not different from wild-type in their response to quinine solutions. There were no differences in null vs. wild-type mice in their consumption of sodium chloride solutions. To determine the cause for reduction of ethanol intake, we studied other ethanol-induced behaviors known to be related to alcohol consumption. There were no differences between null and wild-type mice in ethanol-induced loss of righting reflex, severity of acute ethanol withdrawal or conditioned place preference for ethanol. Weaker conditioned taste aversion to alcohol in null mice may have been caused by weaker rewarding value of the conditioned stimulus (saccharin). When saccharin was replaced by sodium chloride, no differences in conditioned taste aversion to alcohol between knockout and wild-type mice were seen. Thus, deletion of any one of three different genes involved in detection of sweet taste leads to a substantial reduction of alcohol intake without any changes in pharmacological actions of ethanol. PMID:17376151

A common deletion in two gamma ray induced rat pulmonary tumor cell lines.

PubMed

Van Klaveren, P; De Bruijne, J; Van der Winden, H; Kal, H B; Bentvelzen, P

1994-01-01

Subtraction hybridization was performed on normal WAG/Rij rat DNA with DNA from a syngeneic Ir-192 induced pulmonary tumor cell line L37. The residual DNA was amplified by means of sequence-independent PCR. This procedure yielded a sequence, of which multiple copies are present in normal rat DNA. In the tumor line L37 two restriction fragments hybridizing with this repeat sequence are lacking. In another Ir-192 induced pulmonary tumor line, L33, one of these fragments was also lacking. This indicates a common deletion in the two tumor lines.

Intravascular hemolysis induced by phospholipases A2 from the venom of the Eastern coral snake, Micrurus fulvius: Functional profiles of hemolytic and non-hemolytic isoforms.

PubMed

Fernández, María Laura; Quartino, Pablo Yunes; Arce-Bejarano, Ruth; Fernández, Julián; Camacho, Luis F; Gutiérrez, José María; Kuemmel, Daniel; Fidelio, Gerardo; Lomonte, Bruno

2018-04-01

A unique feature of the venom of Micrurus fulvius (Eastern coral snake) is its ability to induce severe intravascular hemolysis in particular species, such as dogs or mice. This effect was previously shown to be induced by distinct phospholipase A 2 (PLA 2 ) isoforms which cause direct hemolysis in vitro, an uncommon finding for such enzymes. The functional profiles of PLA 2 -17, a direct hemolytic enzyme, and PLA 2 -12, a co-existing venom isoform lacking such effect, were compared. The enzymes differed not only in their ability to cause intravascular hemolysis: PLA 2 -17 additionally displayed lethal, myotoxic, and anticoagulant actions, whereas PLA 2 -12 lacked these effects. PLA 2 -12 was much more active in hydrolyzing a monodisperse synthetic substrate than PLA 2 -17, but the catalytic activity of latter was notably higher on a micellar substrate, or towards pure phospholipid artificial monolayers under controlled lateral pressures. Interestingly, PLA 2 -17 could hydrolyze substrate at a pressure of 20 mN m -1 , in contrast to PLA 2 -12 or the non-toxic pancreatic PLA 2 . This suggests important differences in the monolayer penetrating power, which could be related to differences in toxicity. Comparative examination of primary structures and predicted three-dimensional folding of PLA 2 -12 and PLA 2 -17, revealed that differences concentrate in their N-terminal and central regions, leading to variations of the surface properties at the membrane interacting interface. PLA 2 -17 presents a less basic interfacial surface than PLA 2 -12, but more bulky aromatic residues, which could be associated to its higher membrane-penetrating strength. Altogether, these structural and functional comparative observations suggest that the ability of PLA 2 s to penetrate substrate interfaces could be a major determinant of toxicity, perhaps more important than protein surface charge. Copyright © 2017 Elsevier B.V. All rights reserved.

Systemic inflammation in chronic obstructive pulmonary disease and lung cancer: common driver of pulmonary cachexia?

PubMed

Ceelen, Judith J M; Langen, Ramon C J; Schols, Annemie M W J

2014-12-01

In this article, a putative role of systemic inflammation as a driver of pulmonary cachexia induced by either chronic obstructive pulmonary disease or nonsmall cell lung cancer is reviewed. Gaps in current translational research approaches are discussed and alternative strategies are proposed to provide new insights. Activation of the ubiquitin proteasome system has generally been considered a cause of pulmonary cachexia, but current animal models lack specificity and evidence is lacking in nonsmall cell lung cancer and conflicting in chronic obstructive pulmonary disease patients. Recent studies have shown activation of the autophagy-lysosome pathway in both nonsmall cell lung cancer and chronic obstructive pulmonary disease. Myonuclear loss, as a consequence of increased apoptotic events in myofibers, has been suggested in cancer-cachexia-associated muscle atrophy. Plasma transfer on myotube cultures can be used to detect early inflammatory signals in patients and presence of atrophy-inducing activity within the circulation. Comparative clinical research between nonsmall cell lung cancer and chronic obstructive pulmonary disease in different disease stages is useful to unravel disease-specific versus common denominators of pulmonary cachexia.

Tip Vortices of Isolated Wings and Helicopter Rotor Blades.

DTIC Science & Technology

1987-12-01

root to tip, as expected due to the induced downwash of the tip vor- tex and wake vortex sheet. Although the three different tip-caps produce very...the inherent limitation of not being able to model the vortex wake with these equations, although the Euler formulation has in it the necessary...physics to model vorticity transport correctly. These equations basically lack the physical mecha- nism needed to generate the vortex wake . However, in

Behavioural changes induced by N,N-dimethyl-tryptamine in rodents.

PubMed Central

Jenner, P.; Marsden, C. D.; Thanki, C. M.

1980-01-01

1 N,N-Dimethyltryptamine (DMT) in pargyline pretreated rodents induced a dose-dependent behavioural syndrome consisting of hyperactivity, prostration and hindlimb abduction, mild tremor, Straub tail, retropulsion and jerking. 2 In rats pretreated with pargyline, the behavioural syndrome induced by DMT differed from that induced by L-tryptophan or quipazine, in the lack of forepaw treading and head-weaving and in the presence of only mild tremor. 3 The hyperactivity component of the DMT-induced behavioural syndrome in pargyline-pretreated mice was potentiated by cyproheptadine, methergoline, and mianserin, inhibited by cinanserin, haloperidol, pimozide, methiothepin and propranolol, and not affected by 501C67-sulphate and methysergide. 4 The maximal behavioural changes induced by DMT in rats, other than hyperactivity, were unaffected by pretreatment with cyproheptadine, methysergide, and cinanserin. However, propranolol reduced the intensity of all behavioural effects apart from body jerking, and methergoline decreased the duration of prostration. Phenoxybenzamine and haloperidol, in contrast, enhanced prostration. 5 DMT plus pargyline did not induce circling behaviour in mice with a unilateral 6-hydroxy-dopamine lesion of the nigro-striatal pathway. 6 The DMT-induced behavioural syndrome appears to consist of two components, (a) hyperactivity and (b) other behavioural changes. They differ in their response to drugs affecting brain monoamines. The hyperactivity component may be expressed via dopamine mechanisms, but the other behavioural changes are not. The two behaviours do not respond consistently to drugs believed to alter brain 5-hydroxytryptamine function. PMID:6769527

Neuromuscular and muscle-tendon system adaptations to isotonic and isokinetic eccentric exercise.

PubMed

Guilhem, G; Cornu, C; Guével, A

2010-06-01

To present the properties of an eccentric contraction and compare neuromuscular and muscle-tendon system adaptations induced by isotonic and isokinetic eccentric trainings. An eccentric muscle contraction is characterized by the production of muscle force associated to a lengthening of the muscle-tendon system. This muscle solicitation can cause micro lesions followed by a regeneration process of the muscle-tendon system. Eccentric exercise is commonly used in functional rehabilitation for its positive effect on collagen synthesis but also for resistance training to increase muscle strength and muscle mass in athletes. Indeed, eccentric training stimulates muscle hypertrophy, increases the fascicle pennation angle, fascicles length and neural activation, thus inducing greater strength gains than concentric or isometric training programs. Eccentric exercise is commonly performed either against a constant external load (isotonic) or at constant velocity (isokinetic), inducing different mechanical constraints. These different mechanical constraints could induce structural and neural adaptive strategies specific to each type of exercise. The literature tends to show that isotonic mode leads to a greater strength gain than isokinetic mode. This observation could be explained by a greater neuromuscular activation after IT training. However, the specific muscle adaptations induced by each mode remain difficult to determine due to the lack of standardized, comparative studies. 2010 Elsevier Masson SAS. All rights reserved.

A placebo-controlled investigation of synaesthesia-like experiences under LSD.

PubMed

Terhune, Devin B; Luke, David P; Kaelen, Mendel; Bolstridge, Mark; Feilding, Amanda; Nutt, David; Carhart-Harris, Robin; Ward, Jamie

2016-07-29

The induction of synaesthesia in non-synaesthetes has the potential to illuminate the mechanisms that contribute to the development of this condition and the shaping of its phenomenology. Previous research suggests that lysergic acid diethylamide (LSD) reliably induces synaesthesia-like experiences in non-synaesthetes. However, these studies suffer from a number of methodological limitations including lack of a placebo control and the absence of rigorous measures used to test established criteria for genuine synaesthesia. Here we report a pilot study that aimed to circumvent these limitations. We conducted a within-groups placebo-controlled investigation of the impact of LSD on colour experiences in response to standardized graphemes and sounds and the consistency and specificity of grapheme- and sound-colour associations. Participants reported more spontaneous synaesthesia-like experiences under LSD, relative to placebo, but did not differ across conditions in colour experiences in response to inducers, consistency of stimulus-colour associations, or in inducer specificity. Further analyses suggest that individual differences in a number of these effects were associated with the propensity to experience states of absorption in one's daily life. Although preliminary, the present study suggests that LSD-induced synaesthesia-like experiences do not exhibit consistency or inducer-specificity and thus do not meet two widely established criteria for genuine synaesthesia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Transduction of NeuroD2 protein induced neural cell differentiation.

PubMed

Noda, Tomohide; Kawamura, Ryuzo; Funabashi, Hisakage; Mie, Masayasu; Kobatake, Eiry

2006-11-01

NeuroD2, one of the neurospecific basic helix-loop-helix transcription factors, has the ability to induce neural differentiation in undifferentiated cells. In this paper, we show that transduction of NeuroD2 protein induced mouse neuroblastoma cell line N1E-115 into neural differentiation. NeuroD2 has two basic-rich domains, one is nuclear localization signal (NLS) and the other is basic region of basic helix-loop-helix (basic). We constructed some mutants of NeuroD2, ND2(Delta100-115) (lack of NLS), ND2(Delta123-134) (lack of basic) and ND2(Delta100-134) (lack of both NLS and basic) for transduction experiments. Using these proteins, we have shown that NLS region of NeuroD2 plays a role of protein transduction. Continuous addition of NeuroD2 protein resulted in N1E-115 cells adopting neural morphology after 4 days and Tau mRNA expression was increased. These results suggest that neural differentiation can be induced by direct addition of NeuroD2 protein.

Novel Pentameric Structure of the Diarrhea-Inducing Region of the Rotavirus Enterotoxigenic Protein NSP4▿

PubMed Central

Chacko, Anita R.; Arifullah, Mohammed; Sastri, Narayan P.; Jeyakanthan, Jeyaraman; Ueno, Go; Sekar, Kanagaraj; Read, Randy J.; Dodson, Eleanor J.; Rao, Durga C.; Suguna, Kaza

2011-01-01

A novel pentameric structure which differs from the previously reported tetrameric form of the diarrhea-inducing region of the rotavirus enterotoxin NSP4 is reported here. A significant feature of this pentameric form is the absence of the calcium ion located in the core region of the tetrameric structures. The lysis of cells, the crystallization of the region spanning residues 95 to 146 of NSP4 (NSP495-146) of strain ST3 (ST3:NSP495-146) at acidic pH, and comparative studies of the recombinant purified peptide under different conditions by size-exclusion chromatography (SEC) and of the crystal structures suggested pH-, Ca2+-, and protein concentration-dependent oligomeric transitions in the peptide. Since the NSP495-146 mutant lacks the N-terminal amphipathic domain (AD) and most of the C-terminal flexible region (FR), to demonstrate that the pentameric transition is not a consequence of the lack of the N- and C-terminal regions, glutaraldehyde cross-linking of the ΔN72 and ΔN94 mutant proteins, which contain or lack the AD, respectively, but possess the complete C-terminal FR, was carried out. The results indicate the presence of pentamers in preparations of these longer mutants. Detailed SEC analyses of ΔN94 prepared under different conditions, however, revealed protein concentration-dependent but metal ion- and pH-independent pentamer accumulation at high concentrations which dissociated into tetramers and lower oligomers at low protein concentrations. While calcium appeared to stabilize the tetramer, magnesium in particular stabilized the dimer. ΔN72 existed primarily in the multimeric form under all conditions. These findings of a calcium-free NSP4 pentamer and its concentration-dependent and largely calcium-independent oligomeric transitions open up a new dimension in an understanding of the structural basis of its multitude of functions. PMID:21917949

Nature of the endogenous pyrogen (EP) induced by influenza viruses: lack of correlation between EP levels and content of the known pyrogenic cytokines, interleukin 1, interleukin 6 and tumour necrosis factor.

PubMed

Jakeman, K J; Bird, C R; Thorpe, R; Smith, H; Sweet, C

1991-03-01

Fever in influenza results from the release of endogenous pyrogen (EP) following virus-phagocyte interaction and its level correlates with the differing virulence of virus strains. However, the different levels of fever produced in ferrets by intracardial inoculation of EP obtained from the interaction of different virus strains with ferret of human phagocytes did not correlate with the levels of interleukin 1 (IL-1), IL-6 or tumour necrosis factor in the same samples as assayed by conventional in vitro methods. Hence, the EP produced by influenza virus appears to be different to these cytokines.

Lessons learned using different mouse models during space radiation-induced lung tumorigenesis experiments.

PubMed

Wang, Jian; Zhang, Xiangming; Wang, Ping; Wang, Xiang; Farris, Alton B; Wang, Ya

2016-06-01

Unlike terrestrial ionizing radiation, space radiation, especially galactic cosmic rays (GCR), contains high energy charged (HZE) particles with high linear energy transfer (LET). Due to a lack of epidemiologic data for high-LET radiation exposure, it is highly uncertain how high the carcinogenesis risk is for astronauts following exposure to space radiation during space missions. Therefore, using mouse models is necessary to evaluate the risk of space radiation-induced tumorigenesis; however, which mouse model is better for these studies remains uncertain. Since lung tumorigenesis is the leading cause of cancer death among both men and women, and low-LET radiation exposure increases human lung carcinogenesis, evaluating space radiation-induced lung tumorigenesis is critical to enable safe Mars missions. Here, by comparing lung tumorigenesis obtained from different mouse strains, as well as miR-21 in lung tissue/tumors and serum, we believe that wild type mice with a low spontaneous tumorigenesis background are ideal for evaluating the risk of space radiation-induced lung tumorigenesis, and circulating miR-21 from such mice model might be used as a biomarker for predicting the risk. Copyright © 2016 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

Considerations for the Optimization of Induced White Matter Injury Preclinical Models

PubMed Central

Ahmad, Abdullah Shafique; Satriotomo, Irawan; Fazal, Jawad; Nadeau, Stephen E.; Doré, Sylvain

2015-01-01

White matter (WM) injury in relation to acute neurologic conditions, especially stroke, has remained obscure until recently. Current advances in imaging technologies in the field of stroke have confirmed that WM injury plays an important role in the prognosis of stroke and suggest that WM protection is essential for functional recovery and post-stroke rehabilitation. However, due to the lack of a reproducible animal model of WM injury, the pathophysiology and mechanisms of this injury are not well studied. Moreover, producing selective WM injury in animals, especially in rodents, has proven to be challenging. Problems associated with inducing selective WM ischemic injury in the rodent derive from differences in the architecture of the brain, most particularly, the ratio of WM to gray matter in rodents compared to humans, the agents used to induce the injury, and the location of the injury. Aging, gender differences, and comorbidities further add to this complexity. This review provides a brief account of the techniques commonly used to induce general WM injury in animal models (stroke and non-stroke related) and highlights relevance, optimization issues, and translational potentials associated with this particular form of injury. PMID:26322013

Plant Resistance Inducers against Pathogens in Solanaceae Species—From Molecular Mechanisms to Field Application

PubMed Central

Alexandersson, Erik; Mulugeta, Tewodros; Lankinen, Åsa; Liljeroth, Erland; Andreasson, Erik

2016-01-01

This review provides a current summary of plant resistance inducers (PRIs) that have been successfully used in the Solanaceae plant family to protect against pathogens by activating the plant’s own defence. Solanaceous species include many important crops such as potato and tomato. We also present findings regarding the molecular processes after application of PRIs, even if the number of such studies still remains limited in this plant family. In general, there is a lack of patterns regarding the efficiency of induced resistance (IR) both between and within solanaceous species. In many cases, a hypersensitivity-like reaction needs to form in order for the PRI to be efficient. “-Omics” studies have already given insight in the complexity of responses, and can explain some of the differences seen in efficacy of PRIs between and within species as well as towards different pathogens. Finally, examples of field applications of PRIs for solanaceous crops are presented and discussed. We predict that PRIs will play a role in future plant protection strategies in Solanaceae crops if they are combined with other means of disease control in different spatial and temporal combinations. PMID:27706100

Antibody response is required for protection from Theiler's virus-induced encephalitis in C57BL/6 mice in the absence of CD8{sup +} T cells

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

Kang, B.-S.; Palma, Joann P.; Lyman, Michael A.

2005-09-15

Intracerebral infection of susceptible mice with Theiler's murine encephalomyelitis virus (TMEV) induces immune-mediated demyelinating disease and this system serves as a relevant infectious model for human multiple sclerosis. It was previously shown that {beta}{sub 2}M-deficient C57BL/6 mice lacking functional CD8{sup +} T cells display increased viral persistence and enhanced susceptibility to TMEV-induced demyelination, and yet the majority of mice are free of clinical signs. To understand the mechanisms involved in this general resistance of C57BL/6 mice in the absence of CTL responses, mice ({mu}MT) deficient in the B-cell compartment lacking membrane IgM molecules were treated with anti-CD8 antibody and thenmore » infected with TMEV. Although little difference in the proliferative responses of peripheral T cells to UV-inactivated TMEV and the resistance to demyelinating disease was observed between virus-infected {mu}MT and control B6 mice, the levels of CD4{sup +} T cells were higher in the CNS of {mu}MT mice. However, after treatment with anti-CD8 antibody, 100% of the mice displayed clinical gray matter disease and prolonged viral persistence in {mu}MT mice, while only 10% of B6 mice showed clinical symptoms and very low viral persistence. Transfusion of sera from TMEV-infected B6 mice into anti-CD8 antibody-treated {mu}MT mice partially restored resistance to virus-induced encephalitis. These results indicate that the early anti-viral antibody response is also important in the protection from TMEV-induced encephalitis particularly in the absence of CD8{sup +} T cells.« less

γδT cells but not αβT cells contribute to sepsis-induced white matter injury and motor abnormalities in mice.

PubMed

Zhang, Xiaoli; Rocha-Ferreira, Eridan; Li, Tao; Vontell, Regina; Jabin, Darakhshan; Hua, Sha; Zhou, Kai; Nazmi, Arshed; Albertsson, Anna-Maj; Sobotka, Kristina; Ek, Joakim; Thornton, Claire; Hagberg, Henrik; Mallard, Carina; Leavenworth, Jianmei W; Zhu, Changlian; Wang, Xiaoyang

2017-12-20

Infection and sepsis are associated with brain white matter injury in preterm infants and the subsequent development of cerebral palsy. In the present study, we used a neonatal mouse sepsis-induced white matter injury model to determine the contribution of different T cell subsets (αβT cells and γδT cells) to white matter injury and consequent behavioral changes. C57BL/6J wild-type (WT), T cell receptor (TCR) δ-deficient (Tcrd -/- , lacking γδT cells), and TCRα-deficient (Tcra -/- , lacking αβT cells) mice were administered with lipopolysaccharide (LPS) at postnatal day (PND) 2. Brain myelination was examined at PNDs 12, 26, and 60. Motor function and anxiety-like behavior were evaluated at PND 26 or 30 using DigiGait analysis and an elevated plus maze. White matter development was normal in Tcrd -/- and Tcrα -/- compared to WT mice. LPS exposure induced reductions in white matter tissue volume in WT and Tcrα -/- mice, but not in the Tcrd -/- mice, compared with the saline-treated groups. Neither LPS administration nor the T cell deficiency affected anxiety behavior in these mice as determined with the elevated plus maze. DigiGait analysis revealed motor function deficiency after LPS-induced sepsis in both WT and Tcrα -/- mice, but no such effect was observed in Tcrd -/- mice. Our results suggest that γδT cells but not αβT cells contribute to sepsis-induced white matter injury and subsequent motor function abnormalities in early life. Modulating the activity of γδT cells in the early stages of preterm white matter injury might represent a novel therapeutic strategy for the treatment of perinatal brain injury.

Wnt-1 Signaling in Mammary Carcinogenesis

DTIC Science & Technology

2000-04-01

and the notochord (4), Wnt-5A/LRP6 or LRP6 (higher doses) alone induced trunk axis duplication with muscle and neural tissues but lacking head or the... notochord (Fig. lb). It remains unclear whether this is due to quantitative or qualitative differences between Wnt-5a/LRP6 and Wnt-5a/hFz5 co...injections under these experimental conditions. We also analyzed LRP6 effect on neural crest formation, which is another Wnt- dependent developmental process

Influence of harvesting intensity on the floristic composition of natural Mediterranean maritime pine forest

NASA Astrophysics Data System (ADS)

Alday, Josu G.; Martínez-Ruiz, Carolina; Marrs, Rob H.; Bravo, Felipe

2010-05-01

Understorey plant species composition is an important part of forest ecosystems and its conservation is becoming an increasingly frequent objective in forest management plans. However, there is a lack of knowledge of the effect of timber harvesting on the characteristic understorey species in the Mediterranean region. We investigated the effects of three different harvest intensities on the short-term dynamics of understorey vegetation in a natural Maritime pine forest in Spain, and compared the results with uncut controls. Clear-cutting induced both qualitative and quantitative differences with respect to the controls, but intermediate levels of harvesting (25% and 50% removal) induced only quantitative differences. Harvesting reduced the frequency and cover of 56% of characteristic forest species, but only 22% showed an increase. Of the most abundant plant families only the Fabaceae showed a significant response with respect to harvesting intensity. Our findings suggest that Light- and Medium-harvest regimes are better management options than clear-cutting if the aim is to conserve the understorey vegetation.

The gametocidal chromosome as a tool for chromosome manipulation in wheat.

PubMed

Endo, T R

2007-01-01

Many alien chromosomes have been introduced into common wheat (the genus Triticum) from related wild species (the genus Aegilops). Some alien chromosomes have unique genes that secure their existence in the host by causing chromosome breakage in the gametes lacking them. Such chromosomes or genes, called gametocidal (Gc) chromosomes or Gc genes, are derived from different genomes (C, S, S(l) and M(g)) and belong to three different homoeologous groups 2, 3 and 4. The Gc genes of the C and M(g) genomes induce mild, or semi-lethal, chromosome mutations in euploid and alien addition lines of common wheat. Thus, induced chromosomal rearrangements have been identified and established in wheat stocks carrying deletions of wheat and alien (rye and barley) chromosomes or wheat-alien translocations. The gametocidal chromosomes isolated in wheat to date are reviewed here, focusing on their feature as a tool for chromosome manipulation.

The carboxyl-terminal region of staphylococcal enterotoxin type A is required for a fully active molecule.

PubMed Central

Hufnagle, W O; Tremaine, M T; Betley, M J

1991-01-01

Staphylococcal enterotoxin type A (SEA) gene (sea+) mutations were constructed by exonuclease III digestion or cassette mutagenesis. Five different sea mutations that had 1, 3, 7, 39, and 65 codons deleted from the 3' end of sea+ were identified and confirmed by restriction enzyme and nucleotide sequence analyses. Each of these sea mutations was constructed in Escherichia coli and transferred to Staphylococcus aureus by using the plasmid vector pC194. Culture supernatants from the parent S. aureus strain that lacked an enterotoxin gene (negative controls) and from derivatives that contained either sea+ (positive control) or a sea mutation were examined for in vitro sensitivity to degradation by monkey stomach lavage fluid, the ability to cause emesis when administered by an intragastric route to rhesus monkeys, and the ability to induce T-cell proliferation and by Western immunoblot analysis and a gel double-diffusion assay with polyclonal antibodies prepared against SEA. Altered SEAs corresponding to the predicted sizes were visualized by Western blot analysis of culture supernatants for each of the staphylococcal derivatives that contained a sea mutation. The altered SEA that lacked the C-terminal amino acid residue behaved like SEA in all of the assays performed. The altered SEA that lacked the three C-terminal residues of SEA caused T-cell proliferation but was not emetic; this altered SEA was degraded in vitro by monkey stomach lavage fluid and did not reach in the gel double diffusion assay. Altered SEAs that lacked 7, 39, or 65 carboxyl-terminal residues were degraded by stomach lavage fluid in vitro, did not produce an emetic response, and did not induce T-cell proliferation or form a visible reaction in the gel double-diffusion assay. Images PMID:1903773

Fibroblast growth factor rescues brain endothelial cells lacking presenilin 1 from apoptotic cell death following serum starvation.

PubMed

Gama Sosa, Miguel A; De Gasperi, Rita; Hof, Patrick R; Elder, Gregory A

2016-07-22

Presenilin 1 (Psen1) is important for vascular brain development and is known to influence cellular stress responses. To understand the role of Psen1 in endothelial stress responses, we investigated the effects of serum withdrawal on wild type (wt) and Psen1-/- embryonic brain endothelial cells. Serum starvation induced apoptosis in Psen1-/- cells but did not affect wt cells. PI3K/AKT signaling was reduced in serum-starved Psen1-/- cells, and this was associated with elevated levels of phospho-p38 consistent with decreased pro-survival AKT signaling in the absence of Psen1. Fibroblast growth factor (FGF1 and FGF2), but not vascular endothelial growth factor (VEGF) rescued Psen1-/- cells from serum starvation induced apoptosis. Inhibition of FGF signaling induced apoptosis in wt cells under serum withdrawal, while blocking γ-secretase activity had no effect. In the absence of serum, FGF2 immunoreactivity was distributed diffusely in cytoplasmic and nuclear vesicles of wt and Psen1-/- cells, as levels of FGF2 in nuclear and cytosolic fractions were not significantly different. Thus, sensitivity of Psen1-/- cells to serum starvation is not due to lack of FGF synthesis but likely to effects of Psen1 on FGF release onto the cell surface and impaired activation of the PI3K/AKT survival pathway.

Teratocarcinomas induced by embryonic stem (ES) cells lacking vimentin: an approach to study the role of vimentin in tumorigenesis.

PubMed

Langa, F; Kress, C; Colucci-Guyon, E; Khun, H; Vandormael-Pournin, S; Huerre, M; Babinet, C

2000-10-01

Vimentin is a class III intermediate filament protein widely expressed in the developing embryo and in cells of mesenchymal origin in the adult. Vimentin knock-out mice develop and reproduce without any obvious defect. This is an unexpected finding in view of the high degree of conservation of the vimentin gene among vertebrates. However, it does not exclude the possibility of a role for vimentin in pathological conditions, like tumorigenesis. To address this question directly, we have used a teratocarcinoma model involving the injection of ES cells into syngeneic mice. ES cells lacking vimentin were generated from 129/Sv Vim-/- mice with high efficiency. The absence of vimentin did not affect ES cell morphology, viability or growth rate in vitro. Tumours were induced by subcutaneous injection of either Vim-/- or Vim+/+ ES cells into Vim+/+ and Vim-/- mice, in order to analyse the effect of the absence of vimentin in either the tumorigenic cells or the host mice. No significant differences were found in either tumour incidence, size or vascularization of teratocarcinomas obtained with all possible combinations. Vim-/- ES-derived tumours showed the same cellular composition typical of teratocarcinomas induced by wild-type ES cells together with a very similar apoptotic pattern. Taken together, these results demonstrate that in this model vimentin is not essential for efficient tumour growth and differentiation in vivo.

The innate immune response to lower respiratory tract E. Coli infection and the role of the CCL2-CCR2 axis in neonatal mice.

PubMed

McGrath-Morrow, Sharon A; Ndeh, Roland; Collaco, Joseph M; Poupore, Amy K; Dikeman, Dustin; Zhong, Qiong; Singer, Benjamin D; D'Alessio, Franco; Scott, Alan

2017-09-01

Neonates have greater morbidity/mortality from lower respiratory tract infections (LRTI) compared to older children. Lack of conditioning of the pulmonary immune system due to limited environmental exposures and/or infectious challenges likely contributes to the increase susceptibility in the neonate. In this study, we sought to gain insights into the nature and dynamics of the neonatal pulmonary immune response to LRTI using a murine model. Wildtype (WT) and Ccr2 -/- C57BL/6 neonatal and juvenile mice received E. coli or PBS by direct pharyngeal aspiration. Flow cytometry was used to measure immune cell dynamics and identify cytokine-producing cells. Real-time PCR and ELISA were used to measure cytokine/chemokine expression. Innate immune cell recruitment in response to E. coli-induced LRTI was delayed in the neonatal lung compared to juvenile lung. Lung clearance of bacteria was also significantly delayed in the neonate. Ccr2 -/- neonates, which lack an intact CCL2-CCR2 axis, had higher mortality after E. coli challenged than Ccr2 +/+ neonates. A greater percentage of CD8 + T cells and monocytes from WT neonates challenged with E. coli produced TNF compared to controls. The pulmonary immune response to E. coli-induced LRTI differed significantly between neonatal and juvenile mice. Neonates were more susceptible to increasing doses of E. coli and exhibited greater mortality than juveniles. In the absence of an intact CCL2-CCR2 axis, susceptibility to LRTI-induced mortality was further increased in neonatal mice. Taken together these findings underscore the importance of age-related differences in the innate immune response to LRTI during early stages of postnatal life. Copyright © 2017 Elsevier Ltd. All rights reserved.

Comparative Genome Analysis of Three Eukaryotic Parasites with Differing Abilities To Transform Leukocytes Reveals Key Mediators of Theileria-Induced Leukocyte Transformation

PubMed Central

Hayashida, Kyoko; Hara, Yuichiro; Abe, Takashi; Yamasaki, Chisato; Toyoda, Atsushi; Kosuge, Takehide; Suzuki, Yutaka; Sato, Yoshiharu; Kawashima, Shuichi; Katayama, Toshiaki; Wakaguri, Hiroyuki; Inoue, Noboru; Homma, Keiichi; Tada-Umezaki, Masahito; Yagi, Yukio; Fujii, Yasuyuki; Habara, Takuya; Kanehisa, Minoru; Watanabe, Hidemi; Ito, Kimihito; Gojobori, Takashi; Sugawara, Hideaki; Imanishi, Tadashi; Weir, William; Gardner, Malcolm; Pain, Arnab; Shiels, Brian; Hattori, Masahira; Nene, Vishvanath; Sugimoto, Chihiro

2012-01-01

ABSTRACT We sequenced the genome of Theileria orientalis, a tick-borne apicomplexan protozoan parasite of cattle. The focus of this study was a comparative genome analysis of T. orientalis relative to other highly pathogenic Theileria species, T. parva and T. annulata. T. parva and T. annulata induce transformation of infected cells of lymphocyte or macrophage/monocyte lineages; in contrast, T. orientalis does not induce uncontrolled proliferation of infected leukocytes and multiplies predominantly within infected erythrocytes. While synteny across homologous chromosomes of the three Theileria species was found to be well conserved overall, subtelomeric structures were found to differ substantially, as T. orientalis lacks the large tandemly arrayed subtelomere-encoded variable secreted protein-encoding gene family. Moreover, expansion of particular gene families by gene duplication was found in the genomes of the two transforming Theileria species, most notably, the TashAT/TpHN and Tar/Tpr gene families. Gene families that are present only in T. parva and T. annulata and not in T. orientalis, Babesia bovis, or Plasmodium were also identified. Identification of differences between the genome sequences of Theileria species with different abilities to transform and immortalize bovine leukocytes will provide insight into proteins and mechanisms that have evolved to induce and regulate this process. The T. orientalis genome database is available at http://totdb.czc.hokudai.ac.jp/. PMID:22951932

Metabolic responses induced by DNA damage and poly (ADP-ribose) polymerase (PARP) inhibition in MCF-7 cells

PubMed Central

Bhute, Vijesh J.; Palecek, Sean P.

2015-01-01

Genomic instability is one of the hallmarks of cancer. Several chemotherapeutic drugs and radiotherapy induce DNA damage to prevent cancer cell replication. Cells in turn activate different DNA damage response (DDR) pathways to either repair the damage or induce cell death. These DDR pathways also elicit metabolic alterations which can play a significant role in the proper functioning of the cells. The understanding of these metabolic effects resulting from different types of DNA damage and repair mechanisms is currently lacking. In this study, we used NMR metabolomics to identify metabolic pathways which are altered in response to different DNA damaging agents. By comparing the metabolic responses in MCF-7 cells, we identified the activation of poly (ADP-ribose) polymerase (PARP) in methyl methanesulfonate (MMS)-induced DNA damage. PARP activation led to a significant depletion of NAD+. PARP inhibition using veliparib (ABT-888) was able to successfully restore the NAD+ levels in MMS-treated cells. In addition, double strand break induction by MMS and veliparib exhibited similar metabolic responses as zeocin, suggesting an application of metabolomics to classify the types of DNA damage responses. This prediction was validated by studying the metabolic responses elicited by radiation. Our findings indicate that cancer cell metabolic responses depend on the type of DNA damage responses and can also be used to classify the type of DNA damage. PMID:26478723

The Effect of Land Use Changes on Blue Oak Regeneration and Recruitment

Treesearch

Scott Mensing

1991-01-01

Lack of blue oak (Quercus douglasii) saplings and seedlings throughout much of its range has prompted research into the regeneration status of the species. Our ability to assess whether the current lack of regeneration is a natural pattern or a response to human induced environmental change is limited by lack of data on the history of blue oak...

Food protein-induced enterocolitis syndrome: a review of the new guidelines.

PubMed

Leonard, Stephanie A; Pecora, Valentina; Fiocchi, Alessandro Giovanni; Nowak-Wegrzyn, Anna

2018-01-01

Food protein-induced enterocolitis syndrome (FPIES) is a non IgE-mediated gastrointestinal food allergy that presents with delayed vomiting after ingestion primarily in infants. While the pathophysiology of FPIES is poorly understood, the clinical presentation of acute FPEIS reactions has been well characterized. The first International Consensus Guidelines for the Diagnosis and Management of Food Protein-induced Enterocolitis Syndrome were published in 2017 and reviewed epidemiology, clinical presentation, and prognosis of acute and chronic FPIES. The workgroup outlined clinical phenotypes, proposed diagnostic criteria, and made recommendations on management. This article summarizes the guidelines and adds recent updates. FPIES is gaining recognition, however there continues to be delays in diagnosis and misdiagnosis due to overlap of symptoms with over conditions, lack of a diagnostic test, and because some of the common trigger foods are not thought of as allergenic. More research into disease mechanisms and factors influencing differences between populations is needed.

Myelin/oligodendrocyte glycoprotein–deficient (MOG-deficient) mice reveal lack of immune tolerance to MOG in wild-type mice

PubMed Central

Delarasse, Cécile; Daubas, Philippe; Mars, Lennart T.; Vizler, Csaba; Litzenburger, Tobias; Iglesias, Antonio; Bauer, Jan; Della Gaspera, Bruno; Schubart, Anna; Decker, Laurence; Dimitri, Dalia; Roussel, Guy; Dierich, Andrée; Amor, Sandra; Dautigny, André; Liblau, Roland; Pham-Dinh, Danielle

2003-01-01

We studied the immunological basis for the very potent encephalitogenicity of myelin/oligodendrocyte glycoprotein (MOG), a minor component of myelin in the CNS that is widely used to induce experimental autoimmune encephalomyelitis (EAE). For this purpose, we generated a mutant mouse lacking a functional mog gene. This MOG-deficient mouse presents no clinical or histological abnormalities, permitting us to directly assess the role of MOG as a target autoantigen in EAE. In contrast to WT mice, which developed severe EAE following immunization with whole myelin, MOG-deficient mice had a mild phenotype, demonstrating that the anti-MOG response is a major pathogenic component of the autoimmune response directed against myelin. Moreover, while MOG transcripts are expressed in lymphoid organs in minute amounts, both MOG-deficient and WT mice show similar T and B cell responses against the extracellular domain of MOG, including the immunodominant MOG 35–55 T cell epitope. Furthermore, no differences in the fine specificity of the T cell responses to overlapping peptides covering the complete mouse MOG sequence were observed between MOG+/+ and MOG–/– mice. In addition, upon adoptive transfer, MOG-specific T cells from WT mice and those from MOG-deficient mice are equally pathogenic. This total lack of immune tolerance to MOG in WT C57BL/6 mice may be responsible for the high pathogenicity of the anti-MOG immune response as well as the high susceptibility of most animal strains to MOG-induced EAE. PMID:12925695

Analysis of multiple positive feedback paradigms demonstrates a complete absence of LH surges and GnRH activation in mice lacking kisspeptin signaling.

PubMed

Dror, Tal; Franks, Jennifer; Kauffman, Alexander S

2013-06-01

Kisspeptin stimulates gonadotropin-releasing hormone (GnRH) neurons via the kisspeptin receptor, Kiss1r. In rodents, estrogen-responsive kisspeptin neurons in the rostral hypothalamus have been postulated to mediate estrogen-induced positive feedback induction of the preovulatory luteinizing hormone (LH) surge. However, conflicting evidence exists regarding the ability of mice lacking Kiss1r to display LH surges in response to exogenous hormones. Whether the discrepancy reflects different mouse strains used and/or utilization of different surge-induction paradigms is unknown. Here, we tested multiple hormonal paradigms in one Kiss1r knockout (KO) model to see which paradigms, if any, could generate circadian-timed LH surges. Kiss1r KO and wild-type (WT) females were ovariectomized, given sex steroids in various modes, and assessed several days later for LH levels in the morning or evening (when surges occur). Serum LH levels were very low in all morning animals, regardless of genotype or hormonal paradigm. In each paradigm, virtually all WT females displayed clear LH surges in the evening, whereas none of the KO females demonstrated LH surges. The lack of LH surges in KO mice reflects a lack of GnRH secretion rather than diminished pituitary responsiveness from a lifetime lack of GnRH exposure because KO mice responded to GnRH priming with robust LH secretion. Moreover, high cfos-GnRH coexpression was detected in WT females in the evening, whereas low cfos-GnRH coexpression was present in KO females at all time points. Our findings conclusively demonstrate that WT females consistently display LH surges under multiple hormonal paradigms, whereas Kiss1r KO mice do not, indicating that kisspeptin-Kiss1r signaling is mandatory for GnRH/LH surge induction.

Differential effects of biologic versus bisphosphonate inhibition of wear debris-induced osteolysis assessed by longitudinal micro-CT.

PubMed

Tsutsumi, Ryosuke; Hock, Colleen; Bechtold, C Dustin; Proulx, Steven T; Bukata, Susan V; Ito, Hiromu; Awad, Hani A; Nakamura, Takashi; O'Keefe, Regis J; Schwarz, Edward M

2008-10-01

Aseptic loosening of total joint replacements is caused by wear debris-induced osteoclastic bone resorption, for which bisphosphonates (BPs) and RANK antagonists have been developed. Although BPs are effective in preventing metabolic bone loss, they are less effective for inflammatory bone loss. Because this difference has been attributed to the antiapoptotic inflammatory signals that protect osteoclasts from BP-induced apoptosis, but not RANK antagonists, we tested the hypothesis that osteoprotegerin (OPG) is more effective in preventing wear debris-induced osteolysis than zoledronic acid (ZA) or alendronate (Aln) in the murine calvaria model using in vivo micro-CT and traditional histology. Although micro-CT proved to be incompatible with titanium (Ti) particles, we were able to demonstrate a 3.2-fold increase in osteolytic volume over 10 days induced by polyethylene (PE) particles versus sham controls (0.49 +/- 0.23 mm(3) versus 0.15 +/- 0.067 mm(3); p < 0.01). Although OPG and high-dose ZA completely inhibited this PE-induced osteolysis (p < 0.001), pharmacological doses of ZA and Aln were less effective but still reached statistical significance (p < 0.05). Traditional histomorphometry of the sagital suture area of calvaria from both Ti and PE-treated mice confirmed the remarkable suppression of resorption by OPG (p < 0.001) versus the lack of effect by physiological BPs. The differences in drug effects on osteolysis were largely explained by the significant difference in osteoclast numbers observed between OPG versus BPs in both Ti- and PE-treated calvaria; and linear regression analyses that demonstrated a highly significant correlation between osteolysis volume and sagittal suture area versus osteoclast numbers (p < 0.001). (c) 2008 Orthopaedic Research Society.

Environmental novelty and illumination modify ethanol-induced open-field behavioral effects in mice.

PubMed

Fukushiro, Daniela F; Benetti, Liliane F; Josino, Fabiana S; Oliveira, Gabriela P; Fernandes, Maiara deM; Saito, Luis P; Uehara, Regina A; Wuo-Silva, Raphael; Oliveira, Camila S; Frussa-Filho, Roberto

2010-03-01

Both spontaneous and drug-induced animal behaviors can be modified by exposure to novel stimuli or different levels of environmental illumination. However, research into how these factors specifically impact ethanol (ETH)-induced behavioral effects is currently lacking. We aimed to investigate the effects of these two factors, considered separately or in conjunction, on ETH-induced acute hyperlocomotor effect and its sensitization in adult male Swiss mice. Mice were placed in a novel or familiar open-field under normal light (200 lx) or low light (9 lx) immediately after receiving an ip injection of either 1.8 g/kg ETH or saline (SAL). After 7 days, all animals received an ip challenge injection of 1.8 g/kg ETH, and were placed in the open-field under the same light conditions described above. Novelty increased central locomotion and decreased grooming, while low light increased grooming. Acute ETH administration increased both total and peripheral locomotion and these effects were potentiated by low light. Both low light and novelty were able to facilitate ETH-induced locomotor sensitization, which was detected by the central locomotion parameter. However, there was no synergism between the effects of these two modulating factors on ETH-induced behavioral sensitization. We conclude that both the acute behavioral effects of ETH and behavioral sensitization induced by previous administration of this drug can be critically modified by environmental factors. In addition, our study stresses the importance of using different behavioral parameters to evaluate the interaction between environmental factors and ETH effects. (c) 2009 Elsevier Inc. All rights reserved.

Printability of alloys for additive manufacturing

PubMed Central

Mukherjee, T.; Zuback, J. S.; De, A.; DebRoy, T.

2016-01-01

Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is used to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. The findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts. PMID:26796864

Neutral endopeptidase promotes phorbol ester-induced apoptosis in prostate cancer cells by inhibiting neuropeptide-induced protein kinase C delta degradation.

PubMed

Sumitomo, M; Shen, R; Goldberg, J S; Dai, J; Navarro, D; Nanus, D M

2000-12-01

Phorbol esters induce apoptosis in androgen-sensitive LNCaP cells, which express neutral endopeptidase (NEP), but not in androgen-independent prostate cancer (PC) cells, which lack NEP expression. We investigated the role of NEP in PC cell susceptibility to 12-O-tetradecanoylphorbol-13-acetate (TPA). Western analysis showed that expression of NEP and protein kinase Cdelta (PKCdelta) correlated with PC cell sensitivity to TPA-induced growth arrest and apoptosis in LNCaP cells and in TSU-Prl cells expressing an inducible wild-type NEP protein. Inhibition of NEP enzyme activity using the specific NEP inhibitor CGS24592, or inhibition of PKCdelta using Rottlerin at concentrations that inhibit PKCdelta but not PKCalpha, significantly inhibited TPA-induced growth inhibition and cell death. Furthermore, pulse-chase experiments showed PKCdelta is stabilized in LNCaP cells and in TSU-Pr1 cells overexpressing wild-type NEP compared with PC cells lacking NEP expression. This results from NEP inactivation of its neuropeptide substrates (bombesin and endothelin-1), which in the absence of NEP stimulate cSrc kinase activity and induce rapid degradation of PKCdelta protein. These results indicate that expression of enzymatically active NEP by PC cells is necessary for TPA-induced apoptosis, and that NEP inhibits neuropeptide-induced, cSrc-mediated PKCdelta degradation.

Epac Signaling Is Required for Cocaine-Induced Change in AMPA Receptor Subunit Composition in the Ventral Tegmental Area.

PubMed

Liu, Xiaojie; Chen, Yao; Tong, Jiaqing; Reynolds, Ashley M; Proudfoot, Sarah C; Qi, Jinshun; Penzes, Peter; Lu, Youming; Liu, Qing-Song

2016-04-27

Exchange protein directly activated by cAMP (Epac) and protein kinase A (PKA) are intracellular receptors for cAMP. Although PKA and its downstream effectors have been studied extensively in the context of drug addiction, whether and how Epac regulates cellular and behavioral effects of drugs of abuse remain essentially unknown. Epac is known to regulate AMPA receptor (AMPAR) trafficking. Previous studies have shown that a single cocaine exposure in vivo leads to an increase in GluA2-lacking AMPARs in dopamine neurons of the ventral tegmental area (VTA). We tested the hypothesis that Epac mediates cocaine-induced changes in AMPAR subunit composition in the VTA. We report that a single cocaine injection in vivo in wild-type mice leads to inward rectification of EPSCs and renders EPSCs sensitive to a GluA2-lacking AMPAR blocker in VTA dopamine neurons. The cocaine-induced increase in GluA2-lacking AMPARs was absent in Epac2-deficient mice but not in Epac1-deficient mice. In addition, activation of Epac with the selective Epac agonist 8-CPT-2Me-cAMP (8-CPT) recapitulated the cocaine-induced increase in GluA2-lacking AMPARs, and the effects of 8-CPT were mediated by Epac2. We also show that conditioned place preference to cocaine was impaired in Epac2-deficient mice and in mice in which Epac2 was knocked down in the VTA but was not significantly altered in Epac1-deficient mice. Together, these results suggest that Epac2 is critically involved in the cocaine-induced change in AMPAR subunit composition and drug-cue associative learning. Addictive drugs, such as cocaine, induce long-lasting adaptions in the reward circuits of the brain. A single intraperitoneal injection of cocaine leads to changes in the composition and property of the AMPAR that carries excitatory inputs to dopamine neurons. Here, we provide evidence that exchange protein directly activated by cAMP (Epac), a cAMP sensor protein, is required for the cocaine-induced changes of the AMPAR. We found that the effects of cocaine were mimicked by activation of Epac but were blocked by genetic deletion of Epac. Furthermore, cocaine-cue associative learning was impaired in mice lacking Epac. These findings uncovered a critical role of Epac in regulating the cellular and behavioral actions of cocaine. Copyright © 2016 the authors 0270-6474/16/364802-14$15.00/0.

Effect of impaired glucose tolerance on atherosclerotic lesion formation: an evaluation in selectively bred mice with different susceptibilities to glucose intolerance.

PubMed

Asai, Akira; Nagao, Mototsugu; Kawahara, Momoyo; Shuto, Yuki; Sugihara, Hitoshi; Oikawa, Shinichi

2013-12-01

Impaired glucose tolerance (IGT) is an independent risk factor for atherosclerotic cardiovascular disease. However, due to the lack of appropriate animal models, the underlying mechanisms for IGT-induced atherosclerosis remain to be elucidated in vivo. We recently used selective breeding to establish 2 mouse lines with distinctively different susceptibilities to diet-induced glucose intolerance, designated selectively bred diet-induced glucose intolerance-resistant (SDG-R) and SDG-prone (SDG-P), respectively. Here, we assessed atherosclerotic lesion formation in these mice. Female SDG-R and SDG-P mice were fed an atherogenic diet (AD; 1.25% cholesterol, 0.5% sodium cholate, and 36% energy as fat) for 20 weeks (8-28 weeks of age). Oral glucose tolerance tests were performed during the AD-feeding period. Atherosclerotic lesion formation was quantitatively analyzed in serial aortic sinus sections by oil red O staining. Plasma lipids were measured after the AD-feeding period. Glucose tolerance was impaired in SDG-P mice as compared to SDG-R mice over the 20-week AD-feeding period. No significant differences were observed in any plasma lipid measurement between the 2 mouse lines. Aortic sinus atherosclerotic lesion formation in SDG-P mice was approximately 4-fold greater than that in SDG-R mice. In 2 mouse lines with different susceptibilities to diet-induced glucose intolerance, IGT accelerated atherosclerotic lesion formation. These mice may therefore serve as useful in vivo models for investigating the causal role of IGT in the pathogenesis of atherosclerosis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Mesenchymal stem cells protective effect in adriamycin model of nephropathy.

PubMed

Magnasco, Alberto; Corselli, Mirko; Bertelli, Roberta; Ibatici, Adalberto; Peresi, Monica; Gaggero, Gabriele; Cappiello, Valentina; Chiavarina, Barbara; Mattioli, Girolamo; Gusmano, Rosanna; Ravetti, Jean Louis; Frassoni, Francesco; Ghiggeri, Gian Marco

2008-01-01

Mesenchymal stem cells (MSCs) may be of value in regeneration of renal tissue after damage; however, lack of biological knowledge and variability of results in animal models limit their utilization. We studied the effects of MSCs on podocytes in vitro and in vivo utilizing adriamycin (ADR) as a model of renal toxicity. The in vivo experimental approach was carried out in male Sprague-Dawley rats (overall 60 animals) treated with different ADR schemes to induce acute and chronic nephrosis. MSCs were given a) concomitantly to ADR in tail vein or b) in aorta and c) in tail vein 60 days after ADR. Homing was assessed with PKH26-MSCs. MSCs rescued podocytes from apoptosis induced by ADR in vitro. The maximal effect (80% rescue) was obtained with MSCs/podocytes coculture ratio of 1:1 for 72 h. All rats treated with ADR developed nephrosis. MSCs did not modify the clinical parameters (i.e., proteinuria, serum creatinine, lipids) but protected the kidney from severe glomerulosclerosis when given concomitantly to ADR. Rats given MSCs 60 days after ADR developed the same severe renal damage. Only a few MSCs were found in renal tubule-interstitial areas 1-24 h after injection and no MSCs were detected in glomeruli. MSCs reduced apoptosis of podocytes treated with ADR in vitro. Early and repeated MSCs infusion blunted glomerular damage in chronic ADR-induced nephropathy. MSCs did not modify proteinuria and progression to renal failure, which implies lack of regenerative potential in this model.

Mast cells play no role in the pathogenesis of postoperative ileus induced by intestinal manipulation.

PubMed

Gomez-Pinilla, Pedro J; Farro, Giovanna; Di Giovangiulio, Martina; Stakenborg, Nathalie; Némethova, Andrea; de Vries, Annick; Liston, Adrian; Feyerabend, Thorsten B; Rodewald, Hans-Reimer; Rodewald, Hans-Reimwer; Boeckxstaens, Guy E; Matteoli, Gianluca

2014-01-01

Intestinal manipulation (IM) during abdominal surgery results in intestinal inflammation leading to hypomotility or ileus. Mast cell activation is thought to play a crucial role in the pathophysiology of postoperative ileus (POI). However, this conclusion was mainly drawn using mast cell-deficient mouse models with abnormal Kit signaling. These mice also lack interstitial cells of Cajal (ICC) resulting in aberrant gastrointestinal motility even prior to surgery, compromising their use as model to study POI. To avoid these experimental weaknesses we took advantage of a newly developed knock-in mouse model, Cpa3(Cre/+) , devoid of mast cells but with intact Kit signaling. The role of mast cells in the development of POI and intestinal inflammation was evaluated assessing gastrointestinal transit and muscularis externa inflammation after IM in two strains of mice lacking mast cells, i.e. Kit(W-sh/W-sh) and Cpa3(Cre/+) mice, and by use of the mast cell stabilizer cromolyn. Kit(W-sh/W-sh) mice lack ICC networks and already revealed significantly delayed gastrointestinal transit even before surgery. IM did not further delay intestinal transit, but induced infiltration of myeloperoxidase positive cells, expression of inflammatory cytokines and recruitment of monocytes and neutrophils into the muscularis externa. On the contrary, Cpa3(Cre/+) mice have a normal network of ICC and normal gastrointestinal. Surprisingly, IM in Cpa3(Cre/+) mice caused delay in gut motility and intestinal inflammation as in wild type littermates mice (Cpa3(+/+) ). Furthermore, treatment with the mast cell inhibitor cromolyn resulted in an inhibition of mast cells without preventing POI. Here, we confirm that IM induced mast cell degranulation. However, our data demonstrate that mast cells are not required for the pathogenesis of POI in mice. Although there might be species differences between mouse and human, our results argue against mast cell inhibitors as a therapeutic approach to shorten POI.

Mast Cells Play No Role in the Pathogenesis of Postoperative Ileus Induced by Intestinal Manipulation

PubMed Central

Gomez-Pinilla, Pedro J.; Farro, Giovanna; Di Giovangiulio, Martina; Stakenborg, Nathalie; Némethova, Andrea; de Vries, Annick; Liston, Adrian; Feyerabend, Thorsten B.; Rodewald, Hans-Reimwer; Boeckxstaens, Guy E.; Matteoli, Gianluca

2014-01-01

Introduction Intestinal manipulation (IM) during abdominal surgery results in intestinal inflammation leading to hypomotility or ileus. Mast cell activation is thought to play a crucial role in the pathophysiology of postoperative ileus (POI). However, this conclusion was mainly drawn using mast cell-deficient mouse models with abnormal Kit signaling. These mice also lack interstitial cells of Cajal (ICC) resulting in aberrant gastrointestinal motility even prior to surgery, compromising their use as model to study POI. To avoid these experimental weaknesses we took advantage of a newly developed knock-in mouse model, Cpa3Cre/+, devoid of mast cells but with intact Kit signaling. Design The role of mast cells in the development of POI and intestinal inflammation was evaluated assessing gastrointestinal transit and muscularis externa inflammation after IM in two strains of mice lacking mast cells, i.e. KitW-sh/W-sh and Cpa3Cre/+ mice, and by use of the mast cell stabilizer cromolyn. Results KitW-sh/W-sh mice lack ICC networks and already revealed significantly delayed gastrointestinal transit even before surgery. IM did not further delay intestinal transit, but induced infiltration of myeloperoxidase positive cells, expression of inflammatory cytokines and recruitment of monocytes and neutrophils into the muscularis externa. On the contrary, Cpa3Cre/+ mice have a normal network of ICC and normal gastrointestinal. Surprisingly, IM in Cpa3Cre/+ mice caused delay in gut motility and intestinal inflammation as in wild type littermates mice (Cpa3+/+). Furthermore, treatment with the mast cell inhibitor cromolyn resulted in an inhibition of mast cells without preventing POI. Conclusions Here, we confirm that IM induced mast cell degranulation. However, our data demonstrate that mast cells are not required for the pathogenesis of POI in mice. Although there might be species differences between mouse and human, our results argue against mast cell inhibitors as a therapeutic approach to shorten POI. PMID:24416383

Mode of action and human relevance analysis for nuclear receptor-mediated liver toxicity: A case study with phenobarbital as a model constitutive androstane receptor (CAR) activator

PubMed Central

Elcombe, Clifford R.; Peffer, Richard C.; Wolf, Douglas C.; Bailey, Jason; Bars, Remi; Bell, David; Cattley, Russell C.; Ferguson, Stephen S.; Geter, David; Goetz, Amber; Goodman, Jay I.; Hester, Susan; Jacobs, Abigail; Omiecinski, Curtis J.; Schoeny, Rita; Xie, Wen; Lake, Brian G.

2014-01-01

The constitutive androstane receptor (CAR) and pregnane X receptor (PXR) are important nuclear receptors involved in the regulation of cellular responses from exposure to many xenobiotics and various physiological processes. Phenobarbital (PB) is a non-genotoxic indirect CAR activator, which induces cytochrome P450 (CYP) and other xenobiotic metabolizing enzymes and is known to produce liver foci/tumors in mice and rats. From literature data, a mode of action (MOA) for PB-induced rodent liver tumor formation was developed. A MOA for PXR activators was not established owing to a lack of suitable data. The key events in the PB-induced liver tumor MOA comprise activation of CAR followed by altered gene expression specific to CAR activation, increased cell proliferation, formation of altered hepatic foci and ultimately the development of liver tumors. Associative events in the MOA include altered epigenetic changes, induction of hepatic CYP2B enzymes, liver hypertrophy and decreased apoptosis; with inhibition of gap junctional intercellular communication being an associative event or modulating factor. The MOA was evaluated using the modified Bradford Hill criteria for causality and other possible MOAs were excluded. While PB produces liver tumors in rodents, important species differences were identified including a lack of cell proliferation in cultured human hepatocytes. The MOA for PB-induced rodent liver tumor formation was considered to be qualitatively not plausible for humans. This conclusion is supported by data from a number of epidemiological studies conducted in human populations chronically exposed to PB in which there is no clear evidence for increased liver tumor risk. PMID:24180433

ß3 integrin modulates transforming growth factor beta induced (TGFBI) function and paclitaxel response in ovarian cancer cells.

PubMed

Tumbarello, David A; Temple, Jillian; Brenton, James D

2012-05-28

The extracellular matrix (ECM) has a key role in facilitating the progression of ovarian cancer and we have shown recently that the secreted ECM protein TGFBI modulates the response of ovarian cancer to paclitaxel-induced cell death. We have determined TGFBI signaling from the extracellular environment is preferential for the cell surface αvß3 integrin heterodimer, in contrast to periostin, a TGFBI paralogue, which signals primarily via a ß1 integrin-mediated pathway. We demonstrate that suppression of ß1 integrin expression, in ß3 integrin-expressing ovarian cancer cells, increases adhesion to rTGFBI. In addition, Syndecan-1 and -4 expression is dispensable for adhesion to rTGFBI and loss of Syndecan-1 cooperates with the loss of ß1 integrin to further enhance adhesion to rTGFBI. The RGD motif present in the carboxy-terminus of TGFBI is necessary, but not sufficient, for SKOV3 cell adhesion and is dispensable for adhesion of ovarian cancer cells lacking ß3 integrin expression. In contrast to TGFBI, the carboxy-terminus of periostin, lacking a RGD motif, is unable to support adhesion of ovarian cancer cells. Suppression of ß3 integrin in SKOV3 cells increases resistance to paclitaxel-induced cell death while suppression of ß1 integrin has no effect. Furthermore, suppression of TGFBI expression stimulates a paclitaxel resistant phenotype while suppression of fibronectin expression, which primarily signals through a ß1 integrin-mediated pathway, increases paclitaxel sensitivity. Therefore, different ECM components use distinct signaling mechanisms in ovarian cancer cells and in particular, TGFBI preferentially interacts through a ß3 integrin receptor mediated mechanism to regulate the response of cells to paclitaxel-induced cell death.

The protective role of nitric oxide in a neurotoxicant-induced demyelinating model.

PubMed

Arnett, Heather A; Hellendall, Ron P; Matsushima, Glenn K; Suzuki, Kinuko; Laubach, Victor E; Sherman, Paula; Ting, Jenny P-Y

2002-01-01

Demyelination is often associated with acute inflammatory events involving the recruitment-activation of microglia/macrophage, astrocytes, and leukocytes. The ultimate role of inflammatory products in demyelinating disease and in the survival of oligodendrocytes, the myelin forming cells, is unresolved. The current study examines the role of inducible NO synthase (iNOS)-derived NO in a neurotoxicant-induced model of demyelination. NO levels were greatly elevated in the midline corpus callosum during demyelination in genetically intact C57BL/6 mice, and this NO was due solely to the induction of iNOS, as the correlates of NO were not found in mice lacking iNOS. C57BL/6 mice lacking iNOS exhibited more demyelination, but did not display an increased overall cellularity in the corpus callosum, attributable to an unimpeded microglia/macrophage presence. An enhanced course of pathology was noted in mice lacking iNOS. This was associated with a greater depletion of mature oligodendrocytes, most likely due to apoptosis of oligodendrocytes. Microglia and astrocytes did not undergo apoptosis during treatment. Our results suggest a moderately protective role for NO during acute inflammation-association demyelination.

Triangular Assessment of the Etiology of Induced Abortion in Iran: A Qualitative Study

PubMed Central

Motaghi, Zahra; Keramat, Afsaneh; Shariati, Mohammad; Yunesian, Masud

2013-01-01

Background About 46 million induced abortions occur in the world annually. The studies have reported 80000 cases of induced abortions in Iran annually. Objectives This qualitative study was conducted to identify the causes of unsafe abortion in Iran from the standpoint of three groups of experts, women with a history of abortion or unwanted pregnancy and service providers. Patients and Methods A total of 72 in-depth semi structured interviews were conducted in 2012 in Tehran and Shahroud. After coordination with 8 experts, sampling from them was done using the Snowballing method in their offices. Sampling from 28 married and 10 engaged women with a history of unwanted pregnancy or unsafe abortion and 12 providers was done in health care centers and a in number of gynecologists’ and midwives’ offices. Sampling from women with a history of unwanted pregnancy or unsafe abortion such as single women, HIV positive women and drug users, and women who had sexual intercourse for money was started by referring to the social rehabilitation center for women and continued using the snowballing method due to difficulties in accessing them. Participants were from different ethnic groups including Fars, Gilaks, Mazandarani, Arab, Azerbaijani, and Lor. Content analysis was performed on collected data. Results Based on the results of the interviews, participants have abortion for following reasons: 1. Wanted pregnancy (sub categories: fetal abnormalities, Concern about fetal health and lack of trust to prenatal diagnostic methods, Fetal sex, Lack of independent and free decision making regarding pregnancy in women, 2. Unwanted pregnancy (sub-categories: Socio-economic factors, Beliefs and feelings, Lack of information about family planning) 3. Predisposing factors (sub-categories: Lack of information on religious aspects of abortion, Easy access to easy abortion methods). Some people, despite having unwanted pregnancy due to social, economic, cultural and family grounds, continued their pregnancy and did not have an abortion for the following reasons: Religious beliefs, Beliefs (fear of punishment in the afterlife and believing in fate) , Attachment to the unborn baby, Influence of the other people’s opinions (physician, mother or spouse) Late diagnosis of pregnancy, Unsuccessful abortion attempts (Self-treatment, Unsuccessful medical abortion), Economic weakness and arbitrary treatment. Conclusions In the present study, women who continued their pregnancy despite being unwanted were also interviewed. Although they had the same social, economic, cultural, and family problems as women with a history of unsafe abortion and had easy access to abortion, analysis showed that the difference in religious beliefs between the two groups was the most important factor that led women to choose two different approaches. The authors believe that in-depth analysis of people’s beliefs and opinions in this regard and correction of false beliefs plays a crucial role in decreasing the rate of unsafe abortion. PMID:24719694

What is dynamics in quantum gravity?

NASA Astrophysics Data System (ADS)

Małkiewicz, Przemysław

2017-10-01

The appearance of the Hamiltonian constraint in the canonical formalism for general relativity reflects the lack of a fixed external time. The dynamics of general relativistic systems can be expressed with respect to an arbitrarily chosen internal degree of freedom, the so-called internal clock. We investigate the way in which the choice of internal clock determines the quantum dynamics and how much different quantum dynamics induced by different clocks are. We develop our method of comparison by extending the Hamilton-Jacobi theory of contact transformations to include a new type of transformation which transforms both the canonical variables and the internal clock. We employ our method to study the quantum dynamics of the Friedmann-Lemaitre model and obtain semiclassical corrections to the classical dynamics, which depend on the choice of internal clock. For a unique quantisation map we find the abundance of inequivalent semiclassical corrections induced by quantum dynamics taking place in different internal clocks. It follows that the concepts like minimal volume, maximal curvature and the number of quantum bounces, often used to describe quantum effects in cosmological models, depend on the choice of internal clock.

Musical Interfaces: Visualization and Reconstruction of Music with a Microfluidic Two-Phase Flow

PubMed Central

Mak, Sze Yi; Li, Zida; Frere, Arnaud; Chan, Tat Chuen; Shum, Ho Cheung

2014-01-01

Detection of sound wave in fluids can hardly be realized because of the lack of approaches to visualize the very minute sound-induced fluid motion. In this paper, we demonstrate the first direct visualization of music in the form of ripples at a microfluidic aqueous-aqueous interface with an ultra-low interfacial tension. The interfaces respond to sound of different frequency and amplitude robustly with sufficiently precise time resolution for the recording of musical notes and even subsequent reconstruction with high fidelity. Our work shows the possibility of sensing and transmitting vibrations as tiny as those induced by sound. This robust control of the interfacial dynamics enables a platform for investigating the mechanical properties of microstructures and for studying frequency-dependent phenomena, for example, in biological systems. PMID:25327509

The bacterial preparation OK432 induces IL-12p70 secretion in human dendritic cells in a TLR3 dependent manner.

PubMed

Hovden, Arnt-Ove; Karlsen, Marie; Jonsson, Roland; Appel, Silke

2012-01-01

Dendritic cells (DC) used in therapeutic cancer immunotherapy have to be able to stimulate T cells resulting in an immune response that can efficiently target the cancer cells. One of the critical hurdles has been the lack of IL-12p70 production when maturating the DC, which is rectified by using the bacterial preparation OK432 (trade name Picibanil) to mature the cells. In order to identify the mechanism behind OK432 stimulation of DC, we investigated the contribution of different TLR to examine their involvement in IL-12p70 production. By combining different inhibitors of TLR signaling, we demonstrate here that TLR3 is responsible for the IL-12p70 production of DC induced by OK432. Moreover, our data suggest that the ligand triggering IL-12p70 secretion upon TLR3 stimulation is sensitive to proteinase and partly also RNAse treatment. The fact that a bacterial compound like OK432 can activate the TLR3 pathway in human DC is a novel finding. OK432 demonstrates a critical ability to induce IL-12p70 production, which is of great relevance in DC based cancer immunotherapy.

The Bacterial Preparation OK432 Induces IL-12p70 Secretion in Human Dendritic Cells in a TLR3 Dependent Manner

PubMed Central

Hovden, Arnt-Ove; Karlsen, Marie; Jonsson, Roland; Appel, Silke

2012-01-01

Dendritic cells (DC) used in therapeutic cancer immunotherapy have to be able to stimulate T cells resulting in an immune response that can efficiently target the cancer cells. One of the critical hurdles has been the lack of IL-12p70 production when maturating the DC, which is rectified by using the bacterial preparation OK432 (trade name Picibanil) to mature the cells. In order to identify the mechanism behind OK432 stimulation of DC, we investigated the contribution of different TLR to examine their involvement in IL-12p70 production. By combining different inhibitors of TLR signaling, we demonstrate here that TLR3 is responsible for the IL-12p70 production of DC induced by OK432. Moreover, our data suggest that the ligand triggering IL-12p70 secretion upon TLR3 stimulation is sensitive to proteinase and partly also RNAse treatment. The fact that a bacterial compound like OK432 can activate the TLR3 pathway in human DC is a novel finding. OK432 demonstrates a critical ability to induce IL-12p70 production, which is of great relevance in DC based cancer immunotherapy. PMID:22363584

Regulation of Cre recombinase by ligand-induced complementation of inactive fragments.

PubMed

Jullien, Nicolas; Sampieri, François; Enjalbert, Alain; Herman, Jean-Paul

2003-11-01

Cre recombinase is extensively used to engineer the genome of experimental animals. However, its usefulness is still limited by the lack of an efficient temporal control over its activity. To overcome this, we have developed DiCre, a regulatable fragment complementation system for Cre. The enzyme was split into two moieties that were fused to FKBP12 (FK506-binding protein) and FRB (binding domain of the FKBP12-rapamycin-associated protein), respectively. These can be efficiently heterodimerized by rapamycin. Several variants, based on splitting Cre at different sites and using different linker peptides, were tested in an indicator cell line. The fusion proteins, taken separately, had no recombinase activity. Stable transformants, co-expressing complementing fragments based on splitting Cre between Asn59 and Asn60, displayed low background activity affecting 0.05-0.4% of the cells. Rapamycin induced a rapid recombination, reaching 100% by 48-72 h, with an EC50 of 0.02 nM. Thus, ligand-induced dimerization can efficiently regulate Cre, and should be useful to achieve a tight temporal control of its activity, such as in the case of the creation of conditional knock-out animals.

LH responses to single doses of exogenous GnRH by social Mashona mole-rats: a continuum of socially induced infertility in the family Bathyergidae.

PubMed

Bennett, N C; Faulkes, C G; Spinks, A C

1997-07-22

The Mashona mole-rat, Cryptomys darlingi, exhibits an extreme reproductive division of labour. Reproduction in the colony is restricted to a single breeding pair. The non-reproductive male and female colony members are restrained from sexual activity by being familiar and related to one another and the reproductive animals. Circulating basal concentrations of luteinizing hormone (LH) as well as LH levels measured in response to a single exogenous gonadotropin releasing hormone (GnRH) challenge are not significantly different between the reproductive and non-reproductive groups of either sex. Socially induced infertility in both non-reproductive males and females does not result from a reduced pituitary secretion of LH or decreased sensitivity to hypothalamic GnRH, but rather appears to result from an inhibition of reproductive behaviour in these obligate outbreeders. The African mole-rats exhibit a continuum of socially induced infertility with differing social species inhabiting regions of varying degrees of aridity. In this continuum a transition from a predominantly behavioural repression in a social mesic-adapted species through to complete physiological suppression lacking incest avoidance in an arid-adapted eusocial species occurs in this endemic African family of rodents.

Regulation of lipopolysaccharide-inducible genes by MyD88 and Toll/IL-1 domain containing adaptor inducing IFN-beta.

PubMed

Hirotani, Tomonori; Yamamoto, Masahiro; Kumagai, Yutaro; Uematsu, Satoshi; Kawase, Ichiro; Takeuchi, Osamu; Akira, Shizuo

2005-03-11

Macrophages recognize lipopolysaccharide (LPS) by Toll-like receptor 4 and activate inflammatory responses by inducing expression of various genes. TLR4 activates intracellular signaling pathways via TIR domain containing adaptor molecules, MyD88, and Toll/IL-1 domain containing adaptor inducing IFN-beta (TRIF). Although macrophages lacking MyD88 or TRIF showed impaired cytokine production, activation of intracellular signaling molecules still occurred in response to LPS in these cells. In the present study, we implemented cDNA microarrays to investigate the contribution of MyD88 and TRIF in gene expression induced by LPS stimulation. Whereas wild-type macrophages induced 148 genes in response to LPS, macrophages lacking both MyD88 and TRIF did not upregulate any genes in response to LPS. Surprisingly, 80 LPS-inducible genes were redundantly regulated by either MyD88 or TRIF. In contrast, proinflammatory cytokines and chemokines were critically regulated by MyD88 or TRIF alone. Genes critically regulated by MyD88 alone tend to be induced quickly after LPS stimulation and regulated by mRNA stability as well as transcription. Genes known to be induced by type I interferons were simply dependent on TRIF for their expression. Taken together, MyD88 and TRIF play both redundant and distinct roles in LPS-induced gene expression.

Evaluation of edaravone against radiation-induced oral mucositis in mice.

PubMed

Nakajima, Noriko; Watanabe, Shinichi; Kiyoi, Takeshi; Tanaka, Akihiro; Suemaru, Katsuya; Araki, Hiroaki

2015-03-01

Oral mucositis induced by radiotherapy for cancers of the head and neck reduce the quality of life of patients. However, effective therapeutic agents are lacking. Symptomatic treatment involves local anesthesia and analgesia. We focused on the antioxidant effects of edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one; Radicut(®)). Oral mucositis was induced on the tongue tips of mice using a single dose of X-rays (20 Gy). To evaluate the protective effect of edaravone (30 and 300 mg/kg), administration was carried out 30 min before irradiation. Survival, oral mucositis score, myeloperoxidase activity, and levels of 2-Thiobarbituric acid reactive substances were measured, and all were improved compared with those of control mice. A significant difference was not found in terms of survival due to edaravone. Histopathologic findings also highlighted the beneficial features of edaravone. Edaravone reduced the production of reactive oxygen species. These findings suggest that the protective effect of edaravone against radiation-induced oral mucositis is through an antioxidant effect. Copyright © 2015 Japanese Pharmacological Society. Production and hosting by Elsevier B.V. All rights reserved.

The protective effect of lipid emulsion in preventing bupivacaine-induced mitochondrial injury and apoptosis of H9C2 cardiomyocytes.

PubMed

Chen, Zhe; Jin, Zhousheng; Xia, Yun; Zhao, Shishi; Xu, Xuzhong; Papadimos, Thomas J; Wang, Quanguang

2017-11-01

Lipid emulsion (LE) has been shown to be effective in the resuscitation of bupivacaine-induced cardiac arrest, but the precise mechanism of this action has not been fully elucidated. Pursuant to this lack of information on the mechanism in which LE protects the myocardium during bupivacaine-induced toxicity, we explored mitochondrial function and cell apoptosis. H9C2 cardiomyocytes were used in study. Cells were randomly divided in different groups and were cultivated 6 h, 12 h, and 24 h. The mitochondria were extracted and mitochondrial ATP content was measured, as was mitochondrial membrane potential, the concentration of calcium ion (Ca2+), and the activity of Ca2+-ATP enzyme (Ca2+-ATPase). Cells from groups Bup1000, LE group, and Bup1000LE were collected to determine cell viability, cell apoptosis, and electron microscopy scanning of mitochondrial ultrastructure (after 24 h). We found that LE can reverse the inhibition of the mitochondrial function induced by bupivacaine, regulate the concentration of calcium ion in mitochondria, resulting in the protection of myocardial cells from toxicity induced by bupivacaine.

Glucose Induces Mouse β-Cell Proliferation via IRS2, MTOR, and Cyclin D2 but Not the Insulin Receptor

PubMed Central

Stamateris, Rachel E.; Sharma, Rohit B.; Kong, Yahui; Ebrahimpour, Pantea; Panday, Deepika; Ranganath, Pavana; Zou, Baobo; Levitt, Helena; Parambil, Nisha Abraham; O’Donnell, Christopher P.; García-Ocaña, Adolfo

2016-01-01

An important goal in diabetes research is to understand the processes that trigger endogenous β-cell proliferation. Hyperglycemia induces β-cell replication, but the mechanism remains debated. A prime candidate is insulin, which acts locally through the insulin receptor. Having previously developed an in vivo mouse hyperglycemia model, we tested whether glucose induces β-cell proliferation through insulin signaling. By using mice lacking insulin signaling intermediate insulin receptor substrate 2 (IRS2), we confirmed that hyperglycemia-induced β-cell proliferation requires IRS2 both in vivo and ex vivo. Of note, insulin receptor activation was not required for glucose-induced proliferation, and insulin itself was not sufficient to drive replication. Glucose and insulin caused similar acute signaling in mouse islets, but chronic signaling differed markedly, with mammalian target of rapamycin (MTOR) and extracellular signal–related kinase (ERK) activation by glucose and AKT activation by insulin. MTOR but not ERK activation was required for glucose-induced proliferation. Cyclin D2 was necessary for glucose-induced β-cell proliferation. Cyclin D2 expression was reduced when either IRS2 or MTOR signaling was lost, and restoring cyclin D2 expression rescued the proliferation defect. Human islets shared many of these regulatory pathways. Taken together, these results support a model in which IRS2, MTOR, and cyclin D2, but not the insulin receptor, mediate glucose-induced proliferation. PMID:26740601

Complement-induced histamine release from human basophils. III. Effect of pharmacologic agents.

PubMed

Hook, W A; Siraganian, R P

1977-02-01

Human serum activated with zymosan generates a factor (C5a) that releases histamine from autologous basophils. Previously we have presented evidence that this mechanism for C5a-induced release differs from IgE-mediated reactions. The effect of several pharmacologic agents known to alter IgE-mediated release was studied to determine whether they have a similar action on serum-induced release. Deuterium oxide (D2O), which enhances allergic release, inhibited in a concentration-dependent fashion the serum-induced reaction at incubation temperatures of 25 and 32 degrees C. The colchicine-induced inhibition was not reversed by D2O. Cytochalasin B, which gives a variable enhancement of IgE-mediated release, had a marked enhancing effect on the serum-induced reaction in all subjects tested. The following agents known to inhibit the IgE-mediated reaction also inhibited serum-induced release at 25 degrees C: colchicine, dibutyryl cyclic AMP, aminophylline, isoproterenol, cholera toxin, chlorphenesin, diethylcarbamazine, and 2-deoxy-D-glucose. These results suggest that the serum-induced release is modulated by intracellular cyclic AMP, requires energy, and is enhanced by the disruption of microfilaments. The lack of an effect by D2O would suggest that microtubular stabilization is not required. The data can be interpreted to indicate that IgE- and C5a-mediated reactions diverge at a late stage in the histamine release pathway.

Comparison of gain degradation and deep level transient spectroscopy in pnp Si bipolar junction transistors irradiated with different ion species

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

Aguirre, B. A.; Bielejec, E.; Fleming, R. M.

Here, we studied the effect of light ion and heavy ion irradiations on pnp Si BJTs. A mismatch in DLTS deep peak amplitude for devices with same final gain but irradiated with different ion species was observed. Also, different ions cause different gain degradation when the DLTS spectra are matched. Pre-dosed ion-irradiated samples show that ion induced ionization does not account for the differences in DLTS peak height but isochronal annealing studies suggest that light ions produce more VP defects than heavy ions to compensate for the lack of clusters that heavy ions produce. The creation of defect clusters bymore » heavy ions is evident by the higher content of E4 and V* 2 defects compared to light ions.« less

Comparison of gain degradation and deep level transient spectroscopy in pnp Si bipolar junction transistors irradiated with different ion species

DOE PAGES

Aguirre, B. A.; Bielejec, E.; Fleming, R. M.; ...

2016-12-09

Here, we studied the effect of light ion and heavy ion irradiations on pnp Si BJTs. A mismatch in DLTS deep peak amplitude for devices with same final gain but irradiated with different ion species was observed. Also, different ions cause different gain degradation when the DLTS spectra are matched. Pre-dosed ion-irradiated samples show that ion induced ionization does not account for the differences in DLTS peak height but isochronal annealing studies suggest that light ions produce more VP defects than heavy ions to compensate for the lack of clusters that heavy ions produce. The creation of defect clusters bymore » heavy ions is evident by the higher content of E4 and V* 2 defects compared to light ions.« less

DNA vaccination with a plasmid encoding LACK-TSA fusion against Leishmania major infection in BALB/c mice.

PubMed

Maspi, N; Ghaffarifar, F; Sharifi, Z; Dalimi, A; Khademi, S Z

2017-12-01

Vaccination would be the most important strategy for the prevention and elimination of leishmaniasis. The aim of the present study was to compare the immune responses induced following DNA vaccination with LACK (Leishmania analogue of the receptor kinase C), TSA (Thiol-specific-antioxidant) genes alone or LACK-TSA fusion against cutaneous leishmaniasis (CL). Cellular and humoral immune responses were evaluated before and after challenge with Leishmania major (L. major). In addition, the mean lesion size was also measured from 3th week post-infection. All immunized mice showed a partial immunity characterized by higher interferon (IFN)-γ and Immunoglobulin G (IgG2a) levels compared to control groups (p<0.05). IFN-γ/ Interleukin (IL)-4 and IgG2a/IgG1 ratios demonstrated the highest IFN-γ and IgG2a levels in the group receiving LACK-TSA fusion. Mean lesion sizes reduced significantly in all immunized mice compared with control groups at 7th week post-infection (p<0.05). In addition, there was a significant reduction in mean lesion size of LACK-TSA and TSA groups than LACK group after challenge (p<0.05). In the present study, DNA immunization promoted Th1 immune response and confirmed the previous observations on immunogenicity of LACK and TSA antigens against CL. Furthermore, this study demonstrated that a bivalent vaccine can induce stronger immune responses and protection against infectious challenge with L. major.

Biliary versus alcohol-related infected pancreatic necrosis: similarities and differences in the follow-up.

PubMed

Reszetow, Jacek; Hać, Stanisław; Dobrowolski, Sebastian; Stefaniak, Tomasz; Wajda, Zdzisław; Gruca, Zbigniew; Sledziński, Zbigniew; Studniarek, Michał

2007-10-01

Infected pancreatic necrosis (IPN) is a serious complication of acute pancreatitis. Data concerning survivors' quality of life and pancreatic functions are scarce. Follow-up of the patients with alcohol and biliary etiology of IPN treated with open necrosectomy was performed. Twenty-eight survivors after operative treatment (Bradley procedure) of IPN were followed up 24 to 96 months after discharge from the hospital (10 biliary and 18 alcohol patients). Their exocrine and endocrine pancreatic functions and quality of life (Functional Assessment of Chronic Illness Therapy scale) were evaluated. Pancreatic tissue remaining after necrosectomy was visualized by use of contrast-enhanced computed tomography (CT). In 44.4% of alcohol-induced IPN patients, the presence of the whole pancreas was shown on the follow-up CT, contrary to the biliary group, where the partial lack of the pancreas was observed in all cases. Pancreatic tissue calcifications were present on CT in 8 patients of alcohol-induced acute pancreatitis group only. Median stool elastase 1 concentrations were 318.1 U/mL in the biliary group and 238.3 U/mL in the alcohol-induced group (not significant). The Functional Assessment of Chronic Illness Therapy scale showed significantly higher social/family and emotional well-being in patients with biliary acute necrotizing pancreatitis. Patients after alcohol-induced IPN had lower quality of life compared with biliary etiology. Biliary and alcohol-induced IPN patients after surgical treatment have nonsignificant differences of endocrine and exocrine pancreatic functions.

Metabolic myopathies: functional evaluation by different exercise testing approaches.

PubMed

Volpi, L; Ricci, G; Orsucci, D; Alessi, R; Bertolucci, F; Piazza, S; Simoncini, C; Mancuso, M; Siciliano, G

2011-08-01

Metabolic myopathies are a clinically and etiologically heterogeneous group of disorders due to defects in muscular energy metabolism. They include glycogen storage diseases, fatty acid oxidation defects, and mitochondrial disorders. The typical manifestations of a metabolic myopathy are exercise-induced myalgias, exercise intolerance, and cramps. Evaluating subjects with such symptoms is not easy because of the frequent lack of clinical features. Exercise tests are, therefore, reliable screening tools. Here, we discuss the possible role of such exercise testing techniques in the diagnostic approach of a patient with suspected metabolic myopathy.

Labeling and Other Effects of Actinomycin D on Human Chromosomes*

PubMed Central

Miles, Charles P.

1970-01-01

3H-actinomycin D, a guanine-binding agent, labels fixed human chromosomes nonrandomly. Actinomycin D added in G2 inhibits secondary constrictions and breaks chromosomes. There is some tendency for label to be concentrated at the ends of chromosomes and near the centromere. Labeling with 3H-thymidine in the late stage of DNA synthesis shows a different pattern and in general lacks the telomeric concentrations. The sites of actinomycin D-induced breaks do not show good correspondence with the sites of actinomycin D label. Images PMID:5267140

Protective ocular mechanisms in woodpeckers.

PubMed

Wygnanski-Jaffe, T; Murphy, C J; Smith, C; Kubai, M; Christopherson, P; Ethier, C R; Levin, A V

2007-01-01

Woodpeckers possess mechanisms protecting the eye from shaking/impact. Mechanisms available to woodpeckers but not humans may help explain some eye injuries in Shaken Baby syndrome (SBS). Gross dissection and histologic examination of eyes and orbits of seven woodpeckers. All birds showed restricted axial globe movement due to the tight fit within the orbit and fascial connections between the orbital rim and sclera. The sclera was reinforced with cartilage and bone, the optic nerve lacked redundancy, and the vitreous lacked attachments to the posterior pole retina. Woodpecker eyes differ from human infants by an inability of the globe to move axially in the orbit, the sclera to deform, and the vitreous to shear the retina. These findings support current hypotheses that abusive acceleration-deceleration-induced ocular injury in human infants may be related to translation of vitreous within the globe and the globe within the orbit. The woodpecker presents a natural model resistant to mechanical forces that have some similarity to SBS.

The effect of photo-activated glazes on the microhardness of acrylic baseplate resins.

PubMed

Emmanouil, J K; Kavouras, P; Kehagias, Th

2002-01-01

A comparative investigation of acrylic denture base surface microhardness, induced through glazing with different photo-activated liquids. Thermopolymerized acrylic resin Paladon 65 (Kulzer) was used for this study. The samples were mechanically thinned by silicon carbide grinding papers and finally, mechanically polished by alumina pastes. The samples were then glazed with Palaseal, Plaquit and Lightplast-Lack photo-activated liquids. Microhardness tests were carried out via a Zeiss optical microscope equipped with an Anton Paar microhardness tester fitted with a Knoop indenter. Microhardness testing performed on surfaces glazed by Plaquit, Lightplast-Lack, and Palaseal photo-activated liquids showed enhanced microhardness values compared to the mechanically polished acrylic resin denture base material. Comparative microhardness tests performed on acrylic base resin treated with photo-activated acrylic glazes showed that all increases the surface microhardness. The enhancement of surface microhardness of acrylic denture bases suggests that they are likely to resist wear during service.

Isolation of Human Innate Lymphoid Cells.

PubMed

Krabbendam, Lisette; Nagasawa, Maho; Spits, Hergen; Bal, Suzanne M

2018-06-29

Innate lymphoid cells (ILCs) are innate immune cells of lymphoid origin that have important effector and regulatory functions in the first line of defense against pathogens, but also regulate tissue homeostasis, remodeling, and repair. Their function mirrors T helper cells and cytotoxic CD8 + T lymphocytes, but they lack expression of rearranged antigen-specific receptors. Distinct ILC subsets are classified in group 1 ILCs (ILC1s), group 2 ILCs (ILC2s), and group 3 ILCs (ILC3s and lymphoid tissue-inducer cells), based on the expression of transcription factors and the cytokines they produce. As the frequency of ILCs is low, their isolation requires extensive depletion of other cell types. The lack of unique cell surface antigens further complicates the identification of these cells. Here, methods for ILC isolation and characterization from human peripheral blood and different tissues are described. © 2018 by John Wiley & Sons, Inc. © 2018 John Wiley & Sons, Inc.

Printability of alloys for additive manufacturing

DOE PAGES

Mukherjee, T.; Zuback, J. S.; De, A.; ...

2016-01-22

Although additive manufacturing (AM), or three dimensional (3D) printing, provides significant advantages over existing manufacturing techniques, metallic parts produced by AM are susceptible to distortion, lack of fusion defects and compositional changes. Here we show that the printability, or the ability of an alloy to avoid these defects, can be examined by developing and testing appropriate theories. A theoretical scaling analysis is used to test vulnerability of various alloys to thermal distortion. A theoretical kinetic model is used to examine predisposition of different alloys to AM induced compositional changes. A well-tested numerical heat transfer and fluid flow model is usedmore » to compare susceptibilities of various alloys to lack of fusion defects. These results are tested and validated with independent experimental data. Here, the findings presented in this paper are aimed at achieving distortion free, compositionally sound and well bonded metallic parts.« less

CD32a antibodies induce thrombocytopenia and type II hypersensitivity reactions in FCGR2A mice

PubMed Central

Robles-Carrillo, Liza; Davila, Monica; Brodie, Meghan; Desai, Hina; Rivera-Amaya, Mildred; Francis, John L.; Amirkhosravi, Ali

2015-01-01

The CD32a immunoglobulin G (IgG) receptor (Fcγ receptor IIa) is a potential therapeutic target for diseases in which IgG immune complexes (ICs) mediate inflammation, such as heparin-induced thrombocytopenia, rheumatoid arthritis, and systemic lupus erythematosus. Monoclonal antibodies (mAbs) are a promising strategy for treating such diseases. However, IV.3, perhaps the best characterized CD32a-blocking mAb, was recently shown to induce anaphylaxis in immunocompromised “3KO” mice. This anaphylactic reaction required a human CD32a transgene because mice lack an equivalent of this gene. The finding that IV.3 induces anaphylaxis in CD32a-transgenic mice was surprising because IV.3 had long been thought to lack the intrinsic capacity to trigger cellular activation via CD32a. Such an anaphylactic reaction would also limit potential therapeutic applications of IV.3. In the present study, we examine the molecular mechanisms by which IV.3 induces anaphylaxis. We now report that IV.3 induces anaphylaxis in immunocompetent CD32a-transgenic “FCGR2A” mice, along with the novel finding that IV.3 and 2 other well-characterized CD32a-blocking mAbs, AT-10 and MDE-8, also induce severe thrombocytopenia in FCGR2A mice. Using recombinant variants of these same mAbs, we show that IgG “Fc” effector function is necessary for the induction of anaphylaxis and thrombocytopenia in FCGR2A mice. Variants of these mAbs lacking the capacity to activate mouse IgG receptors not only failed to induce anaphylaxis or thrombocytopenia, but also very potently protected FCGR2A mice from near lethal doses of IgG ICs. Our findings show that effector-deficient IV.3, AT-10, and MDE-8 are promising candidates for developing therapeutic mAbs to treat CD32a-mediated diseases. PMID:26396093

Galanin-Expressing GABA Neurons in the Lateral Hypothalamus Modulate Food Reward and Noncompulsive Locomotion

PubMed Central

Hoang, John; Bruce-Keller, Annadora; Berthoud, Hans-Rudolf; Morrison, Christopher D.

2017-01-01

The lateral hypothalamus (LHA) integrates reward and appetitive behavior and is composed of many overlapping neuronal populations. Recent studies associated LHA GABAergic neurons (LHAGABA), which densely innervate the ventral tegmental area (VTA), with modulation of food reward and consumption; yet, LHAGABA projections to the VTA exclusively modulated food consumption, not reward. We identified a subpopulation of LHAGABA neurons that coexpress the neuropeptide galanin (LHAGal). These LHAGal neurons also modulate food reward, but lack direct VTA innervation. We hypothesized that LHAGal neurons may represent a subpopulation of LHAGABA neurons that mediates food reward independent of direct VTA innervation. We used chemogenetic activation of LHAGal or LHAGABA neurons in mice to compare their role in feeding behavior. We further analyzed locomotor behavior to understand how differential VTA connectivity and transmitter release in these LHA neurons influences this behavior. LHAGal or LHAGABA neuronal activation both increased operant food-seeking behavior, but only activation of LHAGABA neurons increased overall chow consumption. Additionally, LHAGal or LHAGABA neuronal activation similarly induced locomotor activity, but with striking differences in modality. Activation of LHAGABA neurons induced compulsive-like locomotor behavior; while LHAGal neurons induced locomotor activity without compulsivity. Thus, LHAGal neurons define a subpopulation of LHAGABA neurons without direct VTA innervation that mediate noncompulsive food-seeking behavior. We speculate that the striking difference in compulsive-like locomotor behavior is also based on differential VTA innervation. The downstream neural network responsible for this behavior and a potential role for galanin as neuromodulator remains to be identified. SIGNIFICANCE STATEMENT The lateral hypothalamus (LHA) regulates motivated feeding behavior via GABAergic LHA neurons. The molecular identity of LHAGABA neurons is heterogeneous and largely undefined. Here we introduce LHAGal neurons as a subset of LHAGABA neurons that lack direct innervation of the ventral tegmental area (VTA). LHAGal neurons are sufficient to drive motivated feeding and locomotor activity similar to LHAGABA neurons, but without inducing compulsive-like behaviors, which we propose to require direct VTA innervation. Our study integrates galanin-expressing LHA neurons into our current understanding of the neuronal circuits and molecular mechanisms of the LHA that contribute to motivated feeding behaviors. PMID:28539422

Conditional transgenesis using Dimerizable Cre (DiCre).

PubMed

Jullien, Nicolas; Goddard, Isabelle; Selmi-Ruby, Samia; Fina, Jean-Luc; Cremer, Harold; Herman, Jean-Paul

2007-12-26

Cre recombinase is extensively used to engineer the genome of experimental animals. However, its usefulness is still limited by the lack of an efficient temporal control over its activity. We have recently developed a conceptually new approach to regulate Cre recombinase, that we have called Dimerizable Cre or DiCre. It is based on splitting Cre into two inactive moieties and fusing them to FKBP12 (FK506-binding protein) and FRB (binding domain of the FKBP12-rapamycin associated protein), respectively. These latter can be efficiently hetero-dimerized by rapamycin, leading to the reinstatement of Cre activity. We have been able to show, using in vitro approaches, that this ligand-induced dimerization is an efficient way to regulate Cre activity, and presents a low background activity together with a high efficiency of recombination following dimerization. To test the in vivo performance of this system, we have, in the present work, knocked-in DiCre into the Rosa26 locus of mice. To evaluate the performance of the DiCre system, mice have been mated with indicator mice (Z/EG or R26R) and Cre-induced recombination was examined following activation of DiCre by rapamycin during embryonic development or after birth of progenies. No recombination could be observed in the absence of treatment of the animals, indicating a lack of background activity of DiCre in the absence of rapamycin. Postnatal rapamycin treatment (one to five daily injection, 10 mg/kg i.p) induced recombination in a number of different tissues of progenies such as liver, heart, kidney, muscle, etc. On the other hand, recombination was at a very low level following in utero treatment of DiCrexR26R mice. In conclusion, DiCre has indeed the potentiality to be used to establish conditional Cre-deleter mice. An added advantage of this system is that, contrary to other modulatable Cre systems, it offers the possibility of obtaining regulated recombination in a combinatorial manner, i.e. induce recombination at any desired time-point specifically in cells characterized by the simultaneous expression of two different promoters.

Probabilistic models to estimate fire-induced cable damage at nuclear power plants

NASA Astrophysics Data System (ADS)

Valbuena, Genebelin R.

Even though numerous PRAs have shown that fire can be a major contributor to nuclear power plant risk, there are some specific areas of knowledge related to this issue, such as the prediction of fire-induced damage to electrical cables and circuits, and their potential effects in the safety of the nuclear power plant, that still constitute a practical enigma, particularly for the lack of approaches/models to perform consistent and objective assessments. This report contains a discussion of three different models to estimate fire-induced cable damage likelihood given a specified fire profile: the kinetic, the heat transfer and the IR "K Factor" model. These models not only are based on statistical analysis of data available in the open literature, but to the greatest extent possible they use physics based principles to describe the underlying mechanism of failures that take place among the electrical cables upon heating due to external fires. The characterization of cable damage, and consequently the loss of functionality of electrical cables in fire is a complex phenomenon that depends on a variety of intrinsic factors such as cable materials and dimensions, and extrinsic factors such as electrical and mechanical loads on the cables, heat flux severity, and exposure time. Some of these factors are difficult to estimate even in a well-characterized fire, not only for the variability related to the unknown material composition and physical arrangements, but also for the lack of objective frameworks and theoretical models to study the behavior of polymeric wire cable insulation under dynamic external thermal insults. The results of this research will (1) help to develop a consistent framework to predict fire-induced cable failure modes likelihood, and (2) develop some guidance to evaluate and/or reduce the risk associated with these failure modes in existing and new power plant facilities. Among the models evaluated, the physics-based heat transfer model takes into account the properties and characteristics of the cables and cable materials, and the characteristics of the thermal insult. This model can be used to estimate the probability of cable damage under different thermal conditions.

The Effects of the Bali Yoga Program for Breast Cancer Patients on Chemotherapy-Induced Nausea and Vomiting: Results of a Partially Randomized and Blinded Controlled Trial.

PubMed

Anestin, Annélie S; Dupuis, Gilles; Lanctôt, Dominique; Bali, Madan

2017-10-01

Complementary and alternative medicine has been shown to be beneficial in reducing chemotherapy-induced nausea and vomiting. However, conclusive results are lacking in order to confirm its usefulness. The purpose of this study was to determine whether a standardized yoga intervention could reduce these adverse symptoms. This was a partially randomized and blinded controlled trial comparing a standardized yoga intervention with standard care. Eligible patients were adults diagnosed with stages I to III breast cancer receiving chemotherapy. Patients randomized to the experimental group participated in an 8-week yoga program. There was no significant difference between the experimental and control groups on chemotherapy-induced nausea and vomiting after 8 weeks. Results suggest the yoga program is not beneficial in managing these adverse symptoms. However, considering preliminary evidence suggesting yoga's beneficial impact in cancer symptom management, methodological limitations should be explored and additional studies should be conducted.

Structure-activity relationships of neoechinulin A analogues with cytoprotection against peroxynitrite-induced PC12 cell death.

PubMed

Kimoto, Kuniaki; Aoki, Toshiaki; Shibata, Yasushi; Kamisuki, Shinji; Sugawara, Fumio; Kuramochi, Kouji; Nakazaki, Atsuo; Kobayashi, Susumu; Kuroiwa, Kenji; Watanabe, Nobuo; Arai, Takao

2007-10-01

Neoechinulin A, an alkaloid from Eurotium rubrum Hiji025, protected neuronal PC12 cells against cell death induced by peroxynitrite derived from SIN-1 (3-(4-morpholinyl)sydnonimine hydrochloride). In this study, we investigated the structure-activity relationships of neoechinulin A and a set of its analogues by using assays to measure anti-nitration and antioxidant activities and cytoprotection against SIN-1-induced PC12 cell death. The presence of the diketopiperazine ring was essential for both the antioxidant and anti-nitration activities of neoechinulin A derivatives. Nevertheless, a derivative lacking the diketopiperazine ring could still protect PC12 cells against SIN-1 cytotoxicity. An acyclic analogue completely lost the cytoprotective effect while retaining its antioxidant/anti-nitration activities. Pre-incubation of the cells with neoechinulin A for at least 12 hours was essential for the cells to gain SIN-1 resistance. These results suggest that neoechinulin A endows the cells with cytoprotection through a biological effect different from the apparent antioxidant/anti-nitration activities.

Adenovirus vector-induced immune responses in nonhuman primates: responses to prime boost regimens.

PubMed

Tatsis, Nia; Lasaro, Marcio O; Lin, Shih-Wen; Haut, Larissa H; Xiang, Zhi Q; Zhou, Dongming; Dimenna, Lauren; Li, Hua; Bian, Ang; Abdulla, Sarah; Li, Yan; Giles-Davis, Wynetta; Engram, Jessica; Ratcliffe, Sarah J; Silvestri, Guido; Ertl, Hildegund C; Betts, Michael R

2009-05-15

In the phase IIb STEP trial an HIV-1 vaccine based on adenovirus (Ad) vectors of the human serotype 5 (AdHu5) not only failed to induce protection but also increased susceptibility to HIV-1 infection in individuals with preexisting neutralizing Abs against AdHu5. The mechanisms underlying the increased HIV-1 acquisition rates have not yet been elucidated. Furthermore, it remains unclear if the lack of the vaccine's efficacy reflects a failure of the concept of T cell-mediated protection against HIV-1 or a product failure of the vaccine. Here, we compared two vaccine regimens based on sequential use of AdHu5 vectors or two different chimpanzee-derived Ad vectors in rhesus macaques that were AdHu5 seropositive or seronegative at the onset of vaccination. Our results show that heterologous booster immunizations with the chimpanzee-derived Ad vectors induced higher T and B cell responses than did repeated immunizations with the AdHu5 vector, especially in AdHu5-preexposed macaques.

Silver nanoparticles: in vivo toxicity in zebrafish embryos and a comparison to silver nitrate

NASA Astrophysics Data System (ADS)

Mosselhy, Dina A.; He, Wei; Li, Dan; Meng, Yaping; Feng, Qingling

2016-08-01

The wide antimicrobial administration of silver nanoparticles (AgNPs) has raised the risks associated with their exposure. However, there is lack of robust toxicological data for the applied AgNPs to be in line with their wide antimicrobial applications. This study therefore set out to assess the in vivo toxicity of two different sizes of AgNPs using zebrafish embryos ( Danio rerio) as a brilliant in vivo model. The pivotal role of size of AgNPs in the toxicity was highlighted, wherein the smaller AgNPs (Ag-9 nm) exhibited more embryo toxicities than the larger particles (Ag-30 nm). Much uncertainty still exists about whether the cause of in vivo toxicity of AgNPs is the physicochemical properties of AgNPs or the released silver ions (Ag+). Therefore, another purpose of this study is to compare the toxicity of AgNPs with silver nitrate (AgNO3) in terms of mortality, hatchability and cardiac rates, and a series of phenotypic endpoints of zebrafish embryos. Collectively, the present results point towards the remarkable size-dependent toxicity of AgNPs. Wherein, the smaller AgNPs (9 ± 2 nm) induce increased mortality rates and decreased hatchability rates than the larger particles (30 ± 5 nm) in a dose-dependent manner. Besides, AgNPs and AgNO3 induce holistic different toxic mortality and hatchability rates. We have also found striking discrepancies in the phenotypic defects that were induced by AgNPs and AgNO3. The significant phenotypic defect induced by AgNPs is the axial deformity, while it is the deposition of Ag+ on the embryonic chorion for AgNO3. Therefore, it is proposed that AgNPs and AgNO3 induce different in vivo toxicities.

Gender-typical olfactory regulation of sexual behavior in goldfish

PubMed Central

Kawaguchi, Yutaro; Nagaoka, Akira; Kitami, Asana; Mitsuhashi, Tomomi; Hayakawa, Youichi; Kobayashi, Makito

2014-01-01

It is known that olfaction is essential for the occurrence of sexual behavior in male goldfish. Sex pheromones from ovulatory females elicit male sexual behavior, chasing, and sperm releasing act. In female goldfish, ovarian prostaglandin F2α (PGF) elicits female sexual behavior, egg releasing act. It has been considered that olfaction does not affect sexual behavior in female goldfish. In the present study, we re-examined the involvement of olfaction in sexual behavior of female goldfish. Olfaction was blocked in male and female goldfish by two methods: nasal occlusion (NO) which blocks the reception of olfactants, and olfactory tract section (OTX) which blocks transmission of olfactory information from the olfactory bulb to the telencephalon. Sexual behavior of goldfish was induced by administration of PGF to females, an established method for inducing goldfish sexual behavior in both sexes. Sexual behavior in males was suppressed by NO and OTX as previously reported because of lack of pheromone stimulation. In females, NO suppressed sexual behavior but OTX did not affect the occurrence of sexual behavior. Females treated with both NO and OTX performed sexual behavior normally. These results indicate that olfaction is essential in female goldfish to perform sexual behavior as in males but in a different manner. The lack of olfaction in males causes lack of pheromonal stimulation, resulting in no behavior elicited. Whereas the results of female experiments suggest that lack of olfaction in females causes strong inhibition of sexual behavior mediated by the olfactory pathway. Olfactory tract section is considered to block the pathway and remove this inhibition, resulting in the resumption of the behavior. By subtract sectioning of the olfactory tract, it was found that this inhibition was mediated by the medial olfactory tracts, not the lateral olfactory tracts. Thus, it is concluded that goldfish has gender-typical olfactory regulation for sexual behavior. PMID:24817840

Lack of collagen VI promotes neurodegeneration by impairing autophagy and inducing apoptosis during aging.

PubMed

Cescon, Matilde; Chen, Peiwen; Castagnaro, Silvia; Gregorio, Ilaria; Bonaldo, Paolo

2016-05-01

Collagen VI is an extracellular matrix (ECM) protein with a broad distribution in different tissues and mostly deposited at the close periphery of the cell surface. Previous studies revealed that collagen VI protects neurons from the toxicity of amyloid-βpeptides and from UV-induced damage. However, the physiological role of this protein in the central nervous system (CNS) remains unknown. Here, we established primary neural cultures from murine cortex and hippocampus, and carried out in vitro and in vivo studies in wild-type and collagen VI null (Col6a1-/-) mice. Col6a1-/- neural cultures displayed an increased incidence of spontaneous apoptosis and higher vulnerability to oxidative stress, accompanied by altered regulation of autophagy with increased p62 protein levels and decreased LC3 lipidation. Analysis of brain sections confirmed increased apoptosis and abnormal regulation of autophagy in the CNS of collagen VI-deficient animals. To investigate the in vivo physiological consequences of these CNS defects, we carried out functional studies and found that motor and memory task performances were impaired in aged Col6a1-/-mice. These findings indicate that lack of collagen VI leads to spontaneous apoptosis and defective autophagy in neural cells, and point at a protective role for this ECM protein in the CNS during physiological aging.

Ablation of Phosphoinositide 3-Kinase-γ Reduces the Severity of Acute Pancreatitis

PubMed Central

Lupia, Enrico; Goffi, Alberto; De Giuli, Paolo; Azzolino, Ornella; Bosco, Ornella; Patrucco, Enrico; Vivaldo, Maria Cristina; Ricca, Marco; Wymann, Matthias P.; Hirsch, Emilio; Montrucchio, Giuseppe; Emanuelli, Giorgio

2004-01-01

In pancreatic acini, the G-protein-activated phosphoinositide 3-kinase-γ (PI3Kγ) regulates several key pathological responses to cholecystokinin hyperstimulation in vitro. Thus, using mice lacking PI3Kγ, we studied the function of this enzyme in vivo in two different models of acute pancreatitis. The disease was induced by supramaximal concentrations of cerulein and by feeding mice a choline-deficient/ethionine-supplemented diet. Although the secretive function of isolated pancreatic acini was identical in mutant and control samples, in both models, genetic ablation of PI3Kγ significantly reduced the extent of acinar cell injury/necrosis. In agreement with a protective role of apoptosis in pancreatitis, PI3Kγ-deficient pancreata showed an increased number of apoptotic acinar cells, as determined by terminal dUTP nick-end labeling and caspase-3 activity. In addition, neutrophil infiltration within the pancreatic tissue was also reduced, suggesting a dual action of PI3Kγ, both in the triggering events within acinar cells and in the subsequent neutrophil recruitment and activation. Finally, the lethality of the choline-deficient/ethionine-supplemented diet-induced pancreatitis was significantly reduced in mice lacking PI3Kγ. Our results thus suggest that inhibition of PI3Kγ may be of therapeutic value in acute pancreatitis. PMID:15579443

Ablation of phosphoinositide 3-kinase-gamma reduces the severity of acute pancreatitis.

PubMed

Lupia, Enrico; Goffi, Alberto; De Giuli, Paolo; Azzolino, Ornella; Bosco, Ornella; Patrucco, Enrico; Vivaldo, Maria Cristina; Ricca, Marco; Wymann, Matthias P; Hirsch, Emilio; Montrucchio, Giuseppe; Emanuelli, Giorgio

2004-12-01

In pancreatic acini, the G-protein-activated phosphoinositide 3-kinase-gamma (PI3K gamma) regulates several key pathological responses to cholecystokinin hyperstimulation in vitro. Thus, using mice lacking PI3K gamma, we studied the function of this enzyme in vivo in two different models of acute pancreatitis. The disease was induced by supramaximal concentrations of cerulein and by feeding mice a choline-deficient/ethionine-supplemented diet. Although the secretive function of isolated pancreatic acini was identical in mutant and control samples, in both models, genetic ablation of PI3K gamma significantly reduced the extent of acinar cell injury/necrosis. In agreement with a protective role of apoptosis in pancreatitis, PI3K gamma-deficient pancreata showed an increased number of apoptotic acinar cells, as determined by terminal dUTP nick-end labeling and caspase-3 activity. In addition, neutrophil infiltration within the pancreatic tissue was also reduced, suggesting a dual action of PI3K gamma, both in the triggering events within acinar cells and in the subsequent neutrophil recruitment and activation. Finally, the lethality of the choline-deficient/ethionine-supplemented diet-induced pancreatitis was significantly reduced in mice lacking PI3K gamma. Our results thus suggest that inhibition of PI3K gamma may be of therapeutic value in acute pancreatitis.

Lacking Ketohexokinase-A Exacerbates Renal Injury in Streptozotocin-induced Diabetic Mice.

PubMed

Doke, Tomohito; Ishimoto, Takuji; Hayasaki, Takahiro; Ikeda, Satsuki; Hasebe, Masako; Hirayama, Akiyoshi; Soga, Tomoyoshi; Kato, Noritoshi; Kosugi, Tomoki; Tsuboi, Naotake; Lanaspa, Miguel A; Johnson, Richard J; Kadomatsu, Kenji; Maruyama, Shoichi

2018-03-28

Ketohexokinase (KHK), a primary enzyme in fructose metabolism, has two isoforms, namely, KHK-A and KHK-C. Previously, we reported that renal injury was reduced in streptozotocin-induced diabetic mice which lacked both isoforms. Although both isoforms express in kidney, it has not been elucidated whether each isoform plays distinct roles in the development of diabetic kidney disease (DKD). The aim of the study is to elucidate the role of KHK-A for DKD progression. Diabetes was induced by five consecutive daily intraperitoneal injections of streptozotocin (50 mg/kg) in C57BL/6 J wild-type mice, mice lacking KHK-A alone (KHK-A KO), and mice lacking both KHK-A and KHK-C (KHK-A/C KO). At 35 weeks, renal injury, inflammation, hypoxia, and oxidative stress were examined. Metabolomic analysis including polyol pathway, fructose metabolism, glycolysis, TCA (tricarboxylic acid) cycle, and NAD (nicotinamide adenine dinucleotide) metabolism in kidney and urine was done. Diabetic KHK-A KO mice developed severe renal injury compared to diabetic wild-type mice, and this was associated with further increases of intrarenal fructose, dihydroxyacetone phosphate (DHAP), TCA cycle intermediates levels, and severe inflammation. In contrast, renal injury was prevented in diabetic KHK-A/C KO mice compared to both wild-type and KHK-A KO diabetic mice. Further, diabetic KHK-A KO mice contained decreased renal NAD + level with the increase of renal hypoxia-inducible factor 1-alpha expression despite having increased renal nicotinamide (NAM) level. These results suggest that KHK-C might play a deleterious role in DKD progression through endogenous fructose metabolism, and that KHK-A plays a unique protective role against the development of DKD. Copyright © 2018. Published by Elsevier Inc.

Acid mediates a prolonged antinociception via substance P signaling in acid-induced chronic widespread pain.

PubMed

Chen, Wei-Nan; Chen, Chih-Cheng

2014-05-21

Substance P is an important neuropeptide released from nociceptors to mediate pain signals. We recently revealed antinociceptive signaling by substance P in acid-sensing ion channel 3 (ASIC3)-expressing muscle nociceptors in a mouse model of acid-induced chronic widespread pain. However, methods to specifically trigger the substance P antinociception were still lacking. Here we show that acid could induce antinociceptive signaling via substance P release in muscle. We prevented the intramuscular acid-induced hyperalgesia by pharmacological inhibition of ASIC3 and transient receptor potential V1 (TRPV1). The antinociceptive effect of non-ASIC3, non-TRPV1 acid signaling lasted for 2 days. The non-ASIC3, non-TRPV1 acid antinociception was largely abolished in mice lacking substance P. Moreover, pretreatment with substance P in muscle mimicked the acid antinociceptive effect and prevented the hyperalgesia induced by next-day acid injection. Acid could mediate a prolonged antinociceptive signaling via the release of substance P from muscle afferent neurons in a non-ASIC3, non-TRPV1 manner.

Minor cell-death defects but reduced tumor latency in mice lacking the BH3-only proteins Bad and Bmf.

PubMed

Baumgartner, F; Woess, C; Pedit, V; Tzankov, A; Labi, V; Villunger, A

2013-01-31

Proapoptotic Bcl-2 family members of the Bcl-2 homology (BH)3-only subgroup are critical for the establishment and maintenance of tissue homeostasis and can mediate apoptotic cell death in response to developmental cues or exogenously induced forms of cell stress. On the basis of the biochemical experiments as well as genetic studies in mice, the BH3-only proteins Bad and Bmf have been implicated in different proapoptotic events such as those triggered by glucose- or trophic factor-deprivation, glucocorticoids, or histone deacetylase inhibition, as well as suppression of B-cell lymphomagenesis upon aberrant expression of c-Myc. To address possible redundancies in cell death regulation and tumor suppression, we generated compound mutant mice lacking both genes. Our studies revealed lack of redundancy in most paradigms of lymphocyte apoptosis tested in tissue culture. Only spontaneous cell death of thymocytes kept in low glucose or that of pre-B cells deprived of cytokines was significantly delayed when both genes were lacking. Of note, despite these minor apoptosis defects we observed compromised lymphocyte homeostasis in vivo that affected mainly the B-cell lineage. Long-term follow-up revealed significantly reduced latency to spontaneous tumor formation in aged mice when both genes were lacking. Together our study suggests that Bad and Bmf co-regulate lymphocyte homeostasis and limit spontaneous transformation by mechanisms that may not exclusively be linked to the induction of lymphocyte apoptosis.

A chloroplast lipoxygenase is required for wound-induced jasmonic acid accumulation in Arabidopsis.

PubMed

Bell, E; Creelman, R A; Mullet, J E

1995-09-12

Plant lipoxygenases are thought to be involved in the biosynthesis of lipid-derived signaling molecules. The potential involvement of a specific Arabidopsis thaliana lipoxygenase isozyme, LOX2, in the biosynthesis of the plant growth regulators jasmonic acid (JA) and abscisic acid was investigated. Our characterization of LOX2 indicates that the protein is targeted to chloroplasts. The physiological role of this chloroplast lipoxygenase was analyzed in transgenic plants where cosuppression reduced LOX2 accumulation. The reduction in LOX2 levels caused no obvious changes in plant growth or in the accumulation of abscisic acid. However, the wound-induced accumulation of JA observed in control plants was absent in leaves of transgenic plants that lacked LOX2. Thus, LOX2 is required for the wound-induced synthesis of the plant growth regulator JA in leaves. We also examined the expression of a wound- and JA-inducible Arabidopsis gene, vsp, in transgenic and control plants. Leaves of transgenic plants lacking LOX2 accumulated less vsp mRNA than did control leaves in response to wounding. This result suggests that wound-induced JA (or some other LOX2-requiring component of the wound response pathway) is involved in the wound-induced regulation of this gene.

Tree mortality across biomes is promoted by drought intensity, lower wood density and higher specific leaf area

USGS Publications Warehouse

Greenwood, Sarah; Ruiz-Benito, Paloma; Martinez-Vilalta, Jordi; Lloret, Francisco; Kitzberger, Thomas; Allen, Craig D.; Fensham, Rod; Laughlin, Daniel C.; Kattge, Jens; Bönisch, Gerhard; Kraft, Nathan J. B.; Jump, Alistair S.

2017-01-01

Drought events are increasing globally, and reports of consequent forest mortality are widespread. However, due to a lack of a quantitative global synthesis, it is still not clear whether drought-induced mortality rates differ among global biomes and whether functional traits influence the risk of drought-induced mortality. To address these uncertainties, we performed a global meta-analysis of 58 studies of drought-induced forest mortality. Mortality rates were modelled as a function of drought, temperature, biomes, phylogenetic and functional groups and functional traits. We identified a consistent global-scale response, where mortality increased with drought severity [log mortality (trees trees−1 year−1) increased 0.46 (95% CI = 0.2–0.7) with one SPEI unit drought intensity]. We found no significant differences in the magnitude of the response depending on forest biomes or between angiosperms and gymnosperms or evergreen and deciduous tree species. Functional traits explained some of the variation in drought responses between species (i.e. increased from 30 to 37% when wood density and specific leaf area were included). Tree species with denser wood and lower specific leaf area showed lower mortality responses. Our results illustrate the value of functional traits for understanding patterns of drought-induced tree mortality and suggest that mortality could become increasingly widespread in the future.

Inflammasomes and Their Role in Innate Immunity of Sexually Transmitted Infections

PubMed Central

Verma, Vivek; Dhanda, Rakesh Singh; Møller, Niels Frimodt; Yadav, Manisha

2016-01-01

Inflammasomes are multiprotein complexes present in the cytosol as pattern recognition receptors or as sensors of damage-associated molecular patterns. After recognition of microbe-associated molecular patterns or host-derived danger signals, nucleotide oligomerization domain-like receptors oligomerize to form inflammasomes. The activation of inflammasomes results in an alarm, which is raised to alert adjacent cells through the processing and release of a number of other substrates present in the cytosol. A wide array of inflammasomes and their adapter molecules have been identified in the host’s innate immune system in response to various pathogens. Components of specific pathogens activate different inflammasomes, which once activated in response to pathogen-induced infection, induce the activation of caspases, and the release of mature forms of interleukin-1β (IL-1β) and IL-18. Identifying the mechanisms underlying pathogen-induced inflammasome activation is important if we are to develop novel therapeutic strategies to target sexually transmitted infections (STIs) related pathogens. This information is currently lacking in literature. In this review, we have discussed the role of various inflammasomes in sensing different STIs, as well as the beneficial or detrimental effects of inflammasome signaling in host resistance. Additionally, we have discussed both canonical and non-canonical processing of IL-1β induced with respect to particular infections. Overall, these findings transform our understanding of both the basic biology and clinical relevance of inflammasomes. PMID:27994587

Tree mortality across biomes is promoted by drought intensity, lower wood density and higher specific leaf area.

PubMed

Greenwood, Sarah; Ruiz-Benito, Paloma; Martínez-Vilalta, Jordi; Lloret, Francisco; Kitzberger, Thomas; Allen, Craig D; Fensham, Rod; Laughlin, Daniel C; Kattge, Jens; Bönisch, Gerhard; Kraft, Nathan J B; Jump, Alistair S

2017-04-01

Drought events are increasing globally, and reports of consequent forest mortality are widespread. However, due to a lack of a quantitative global synthesis, it is still not clear whether drought-induced mortality rates differ among global biomes and whether functional traits influence the risk of drought-induced mortality. To address these uncertainties, we performed a global meta-analysis of 58 studies of drought-induced forest mortality. Mortality rates were modelled as a function of drought, temperature, biomes, phylogenetic and functional groups and functional traits. We identified a consistent global-scale response, where mortality increased with drought severity [log mortality (trees trees -1  year -1 ) increased 0.46 (95% CI = 0.2-0.7) with one SPEI unit drought intensity]. We found no significant differences in the magnitude of the response depending on forest biomes or between angiosperms and gymnosperms or evergreen and deciduous tree species. Functional traits explained some of the variation in drought responses between species (i.e. increased from 30 to 37% when wood density and specific leaf area were included). Tree species with denser wood and lower specific leaf area showed lower mortality responses. Our results illustrate the value of functional traits for understanding patterns of drought-induced tree mortality and suggest that mortality could become increasingly widespread in the future. © 2017 John Wiley & Sons Ltd/CNRS.

Constitutive Overexpression of Human Erythropoietin Protects the Mouse Retina against Induced But Not Inherited Retinal Degeneration

PubMed Central

Grimm, Christian; Wenzel, Andreas; Stanescu, Dinu; Samardzija, Marijana; Hotop, Svenja; Groszer, Mathias; Naash, Muna; Gassmann, Max; Remé, Charlotte

2010-01-01

Elevation of erythropoietin (Epo) concentrations by hypoxic preconditioning or application of recombinant human Epo (huEpo) protects the mouse retina against light-induced degeneration by inhibiting photoreceptor cell apoptosis. Because photoreceptor apoptosis is also the common path to cell loss in retinal dystrophies such as retinitis pigmentosa (RP), we tested whether high levels of huEpo would reduce apoptotic cell death in two mouse models of human RP. We combined the two respective mutant mouse lines with a transgenic line (tg6) that constitutively overexpresses huEpo mainly in neural tissues. Transgenic expression of huEpo caused constitutively high levels of Epo in the retina and protected photoreceptors against light-induced degeneration; however, the presence of high levels of huEpo did not affect the course or the extent of retinal degeneration in a light-independent (rd1) and a light-accelerated (VPP) mouse model of RP. Similarly, repetitive intraperitoneal injections of recombinant huEpo did not protect the retina in the rd1 and the VPP mouse. Lack of neuroprotection by Epo in the two models of inherited retinal degeneration was not caused by adaptational downregulation of Epo receptor. Our results suggest that apoptotic mechanisms during acute, light-induced photoreceptor cell death differ from those in genetically based retinal degeneration. Therapeutic intervention with cell death in inherited retinal degeneration may therefore require different drugs and treatments. PMID:15215287

Diffusion dynamics of the Keap1–Cullin3 interaction in single live cells

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

Baird, Liam; Dinkova-Kostova, Albena T., E-mail: a.dinkovakostova@dundee.ac.uk; Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD

2013-03-29

Highlights: ► We developed a quantitative FRAP-based system to study the Keap1–Cul3 interaction. ► We show that Keap1–EGFP and mCherry–Cul3 interact in single live cells. ► We used inducers which target distinct cysteine sensors of Keap1 and differ 4000-fold in potency. ► Inducers cause Nrf2 stabilization, nuclear translocation, and target gene expression. ► Inducers of four different types do not dissociate the Keap1–EGFP:mCherry–Cul3 complex. -- Abstract: Transcription factor NF-E2 p45-related factor 2 (Nrf2) regulates the expression of a network of genes encoding drug-detoxification, anti-inflammatory, and metabolic enzymes, as well as proteins involved in the regulation of cellular redox homeostasis. Undermore » basal conditions, Kelch-like ECH associated protein 1 (Keap1) targets Nrf2 for ubiquitination and proteasomal degradation via association with Cullin3 (Cul3)-based Rbx1 E3 ubiquitin ligase. Various small molecules (inducers) activate Nrf2 leading to upregulation of cytoprotective gene expression. Inducers chemically modify specific cysteine residues of Keap1 which ultimately loses its ability to target Nrf2 for degradation. Dissociation of the Keap1–Cul3 complex by inducers is one possible mechanism, but evidence in single live cells is lacking. To investigate the diffusion dynamics of the Keap1–Cul3 interaction and the effect of inducers, we developed a quantitative fluorescence recovery after photobleaching (FRAP)-based system using Keap1–EGFP and mCherry–Cul3 fusion proteins. We show that Keap1–EGFP and mCherry–Cul3 interact in single live cells. Exposure for 1 h to small-molecule inducers of 4 different types, the oleanane triterpenoid CDDO, the isothiocyanate sulforaphane, the sulfoxythiocarbamate STCA, and the oxidant hydrogen peroxide which target distinct cysteine sensors within Keap1 with potencies which differ by nearly 4000-fold, does not dissociate the Keap1–Cul3 complex. As inducers cause conformational changes in Keap1, we conclude that changes in conformation rather than dissociation from Cul3 inactivate the repressor function of Keap1 leading to Nrf2 stabilization.« less

SPONTANEOUSLY HYPERTENSIVE RATS ARE SUSCEPTIBLE TO AIRWAY DISEASE INDUCED BY SULFUR DIOXIDE

EPA Science Inventory

Rodent models of chronic pulmonary diseases induced by sulfur dioxide (SO2), elastase or tobacco smoke have limited utility because of their lack of chronicity of inflammation, and they demonstrate limited sensitivity to a given experimental manipulation. We hypothesized that dis...

Lack of Collagen VI Promotes Wound-Induced Hair Growth.

PubMed

Chen, Peiwen; Cescon, Matilde; Bonaldo, Paolo

2015-10-01

Collagen VI is an extracellular matrix molecule that is abundantly expressed in the skin. However, the role of collagen VI in hair follicle growth is unknown. Here, we show that collagen VI is strongly deposited in hair follicles, and is markedly upregulated by skin wounding. Lack of collagen VI in Col6a1(-/-) mice delays hair cycling and growth under physiological conditions, but promotes wound-induced hair regrowth without affecting skin regeneration. Conversely, addition of purified collagen VI rescues the abnormal wound-induced hair regrowth in Col6a1(-/-) mice. Mechanistic studies revealed that the increased wound-induced hair regrowth of Col6a1(-/-) mice is triggered by activation of the Wnt/β-catenin signaling pathway, and is abolished by inhibition of this pathway. These findings highlight the essential relationships between extracellular matrix (ECM) and hair follicle regeneration, and suggest that collagen VI could be a potential therapeutic target for hair loss and other skin-related diseases.

Environmental and genetic factors support the dissociation between α-synuclein aggregation and toxicity.

PubMed

Villar-Piqué, Anna; Lopes da Fonseca, Tomás; Sant'Anna, Ricardo; Szegö, Éva Mónika; Fonseca-Ornelas, Luis; Pinho, Raquel; Carija, Anita; Gerhardt, Ellen; Masaracchia, Caterina; Abad Gonzalez, Enrique; Rossetti, Giulia; Carloni, Paolo; Fernández, Claudio O; Foguel, Debora; Milosevic, Ira; Zweckstetter, Markus; Ventura, Salvador; Outeiro, Tiago Fleming

2016-10-18

Synucleinopathies are a group of progressive disorders characterized by the abnormal aggregation and accumulation of α-synuclein (aSyn), an abundant neuronal protein that can adopt different conformations and biological properties. Recently, aSyn pathology was shown to spread between neurons in a prion-like manner. Proteins like aSyn that exhibit self-propagating capacity appear to be able to adopt different stable conformational states, known as protein strains, which can be modulated both by environmental and by protein-intrinsic factors. Here, we analyzed these factors and found that the unique combination of the neurodegeneration-related metal copper and the pathological H50Q aSyn mutation induces a significant alteration in the aggregation properties of aSyn. We compared the aggregation of WT and H50Q aSyn with and without copper, and assessed the effects of the resultant protein species when applied to primary neuronal cultures. The presence of copper induces the formation of structurally different and less-damaging aSyn aggregates. Interestingly, these aggregates exhibit a stronger capacity to induce aSyn inclusion formation in recipient cells, which demonstrates that the structural features of aSyn species determine their effect in neuronal cells and supports a lack of correlation between toxicity and inclusion formation. In total, our study provides strong support in favor of the hypothesis that protein aggregation is not a primary cause of cytotoxicity.

Environmental and genetic factors support the dissociation between α-synuclein aggregation and toxicity

PubMed Central

Villar-Piqué, Anna; Lopes da Fonseca, Tomás; Sant’Anna, Ricardo; Szegö, Éva Mónika; Fonseca-Ornelas, Luis; Pinho, Raquel; Carija, Anita; Gerhardt, Ellen; Masaracchia, Caterina; Abad Gonzalez, Enrique; Rossetti, Giulia; Carloni, Paolo; Fernández, Claudio O.; Foguel, Debora; Milosevic, Ira; Zweckstetter, Markus; Ventura, Salvador; Outeiro, Tiago Fleming

2016-01-01

Synucleinopathies are a group of progressive disorders characterized by the abnormal aggregation and accumulation of α-synuclein (aSyn), an abundant neuronal protein that can adopt different conformations and biological properties. Recently, aSyn pathology was shown to spread between neurons in a prion-like manner. Proteins like aSyn that exhibit self-propagating capacity appear to be able to adopt different stable conformational states, known as protein strains, which can be modulated both by environmental and by protein-intrinsic factors. Here, we analyzed these factors and found that the unique combination of the neurodegeneration-related metal copper and the pathological H50Q aSyn mutation induces a significant alteration in the aggregation properties of aSyn. We compared the aggregation of WT and H50Q aSyn with and without copper, and assessed the effects of the resultant protein species when applied to primary neuronal cultures. The presence of copper induces the formation of structurally different and less-damaging aSyn aggregates. Interestingly, these aggregates exhibit a stronger capacity to induce aSyn inclusion formation in recipient cells, which demonstrates that the structural features of aSyn species determine their effect in neuronal cells and supports a lack of correlation between toxicity and inclusion formation. In total, our study provides strong support in favor of the hypothesis that protein aggregation is not a primary cause of cytotoxicity. PMID:27708160

The pea SAD short-chain dehydrogenase/reductase: quinone reduction, tissue distribution, and heterologous expression.

PubMed

Scherbak, Nikolai; Ala-Häivälä, Anneli; Brosché, Mikael; Böwer, Nathalie; Strid, Hilja; Gittins, John R; Grahn, Elin; Eriksson, Leif A; Strid, Åke

2011-04-01

The pea (Pisum sativum) tetrameric short-chain alcohol dehydrogenase-like protein (SAD) family consists of at least three highly similar members (SAD-A, -B, and -C). According to mRNA data, environmental stimuli induce SAD expression. The aim of this study was to characterize the SAD proteins by examining their catalytic function, distribution in pea, and induction in different tissues. In enzyme activity assays using a range of potential substrates, the SAD-C enzyme was shown to reduce one- or two-ring-membered quinones lacking long hydrophobic hydrocarbon tails. Immunological assays using a specific antiserum against the protein demonstrated that different tissues and cell types contain small amounts of SAD protein that was predominantly located within epidermal or subepidermal cells and around vascular tissue. Particularly high local concentrations were observed in the protoderm of the seed cotyledonary axis. Two bow-shaped rows of cells in the ovary and the placental surface facing the ovule also exhibited considerable SAD staining. Ultraviolet-B irradiation led to increased staining in epidermal and subepidermal cells of leaves and stems. The different localization patterns of SAD suggest functions both in development and in responses to environmental stimuli. Finally, the pea SAD-C promoter was shown to confer heterologous wound-induced expression in Arabidopsis (Arabidopsis thaliana), which confirmed that the inducibility of its expression is regulated at the transcriptional level.

The Pea SAD Short-Chain Dehydrogenase/Reductase: Quinone Reduction, Tissue Distribution, and Heterologous Expression1[W][OA

PubMed Central

Scherbak, Nikolai; Ala-Häivälä, Anneli; Brosché, Mikael; Böwer, Nathalie; Strid, Hilja; Gittins, John R.; Grahn, Elin; Eriksson, Leif A.; Strid, Åke

2011-01-01

The pea (Pisum sativum) tetrameric short-chain alcohol dehydrogenase-like protein (SAD) family consists of at least three highly similar members (SAD-A, -B, and -C). According to mRNA data, environmental stimuli induce SAD expression. The aim of this study was to characterize the SAD proteins by examining their catalytic function, distribution in pea, and induction in different tissues. In enzyme activity assays using a range of potential substrates, the SAD-C enzyme was shown to reduce one- or two-ring-membered quinones lacking long hydrophobic hydrocarbon tails. Immunological assays using a specific antiserum against the protein demonstrated that different tissues and cell types contain small amounts of SAD protein that was predominantly located within epidermal or subepidermal cells and around vascular tissue. Particularly high local concentrations were observed in the protoderm of the seed cotyledonary axis. Two bow-shaped rows of cells in the ovary and the placental surface facing the ovule also exhibited considerable SAD staining. Ultraviolet-B irradiation led to increased staining in epidermal and subepidermal cells of leaves and stems. The different localization patterns of SAD suggest functions both in development and in responses to environmental stimuli. Finally, the pea SAD-C promoter was shown to confer heterologous wound-induced expression in Arabidopsis (Arabidopsis thaliana), which confirmed that the inducibility of its expression is regulated at the transcriptional level. PMID:21343423

Absence of opioid stress-induced analgesia in mice lacking beta-endorphin by site-directed mutagenesis.

PubMed

Rubinstein, M; Mogil, J S; Japón, M; Chan, E C; Allen, R G; Low, M J

1996-04-30

A physiological role for beta-endorphin in endogenous pain inhibition was investigated by targeted mutagenesis of the proopiomelanocortin gene in mouse embryonic stem cells. The tyrosine codon at position 179 of the proopiomelanocortin gene was converted to a premature translational stop codon. The resulting transgenic mice display no overt developmental or behavioral alterations and have a normally functioning hypothalamic-pituitary-adrenal axis. Homozygous transgenic mice with a selective deficiency of beta-endorphin exhibit normal analgesia in response to morphine, indicating the presence of functional mu-opiate receptors. However, these mice lack the opioid (naloxone reversible) analgesia induced by mild swim stress. Mutant mice also display significantly greater nonopioid analgesia in response to cold water swim stress compared with controls and display paradoxical naloxone-induced analgesia. These changes may reflect compensatory upregulation of alternative pain inhibitory mechanisms.

Adenovirus E1A and E1B-19K Proteins Protect Human Hepatoma Cells from Transforming Growth Factor β1-induced Apoptosis

PubMed Central

Tarakanova, Vera L.; Wold, William S. M.

2009-01-01

Primary and some transformed hepatocytes undergo apoptosis in response to transforming growth factor β1 (TGFβ). We report that infection with species C human adenovirus conferred resistance to TGFβ-induced apoptosis in human hepatocellular carcinoma cells (Huh-7). Protection against TGFβ-mediated cell death in adenovirus-infected cells correlated with the maintenance of normal nuclear morphology, lack of pro-caspases 8 and 3 processing, maintenance of the mitochondrial membrane potential, and lack of cellular DNA degradation. The TGFβ pro-apoptotic signaling pathway was blocked upstream of mitochondria in adenovirus-infected cells. Both the N-terminal sequences of the E1A proteins and the E1B-19K protein were necessary to protect infected cells against TGFβ-induced apoptosis. PMID:19854227

[Socioeconomic pathology as a cause of regional differences in the prevalence of metabolic syndrome and pregnancy-induced hypertension].

PubMed

López-Jaramillo, Patricio; Pradilla, Lina P; Castillo, Víctor R; Lahera, Vicente

2007-02-01

The epidemic of cardiovascular disease being experienced by developing countries has resulted in a debate about the possible existence of regional differences in etiology and pathophysiology that could be associated with socio-economic factors. Clear demonstration of these differences is important because there may be a need for different approaches to prevention, diagnosis and treatment. There is some evidence that there are differences between populations in developed and developing countries in the pathophysiologic mechanisms underlying pregnancy-induced hypertension and metabolic syndrome, just as there are in the relative weightings of risk factors that predict the appearance of these conditions. Observations in our country suggest that increasing exposure to changes in lifestyle brought about by the consumer society (e.g., a lack of exercise, and a high-fat, high-calorie diet) results in a natural biological response (e.g., obesity, metabolic syndrome, and diabetes) that increases the risk of cardiovascular disease. We propose that the term socioeconomic pathology should be used to describe these changes associated with modern society so that they can be differentiated and considered in isolation from socioeconomic factors and other risk factors. We regard the interaction between these various factors as the most important cause of the rapidly increasing incidence of cardiovascular disease observed in developing countries in recent years.

Modeling xeroderma pigmentosum associated neurological pathologies with patients-derived iPSCs.

PubMed

Fu, Lina; Xu, Xiuling; Ren, Ruotong; Wu, Jun; Zhang, Weiqi; Yang, Jiping; Ren, Xiaoqing; Wang, Si; Zhao, Yang; Sun, Liang; Yu, Yang; Wang, Zhaoxia; Yang, Ze; Yuan, Yun; Qiao, Jie; Izpisua Belmonte, Juan Carlos; Qu, Jing; Liu, Guang-Hui

2016-03-01

Xeroderma pigmentosum (XP) is a group of genetic disorders caused by mutations of XP-associated genes, resulting in impairment of DNA repair. XP patients frequently exhibit neurological degeneration, but the underlying mechanism is unknown, in part due to lack of proper disease models. Here, we generated patient-specific induced pluripotent stem cells (iPSCs) harboring mutations in five different XP genes including XPA, XPB, XPC, XPG, and XPV. These iPSCs were further differentiated to neural cells, and their susceptibility to DNA damage stress was investigated. Mutation of XPA in either neural stem cells (NSCs) or neurons resulted in severe DNA damage repair defects, and these neural cells with mutant XPA were hyper-sensitive to DNA damage-induced apoptosis. Thus, XP-mutant neural cells represent valuable tools to clarify the molecular mechanisms of neurological abnormalities in the XP patients.

Role of nanoparticles generation in the formation of femtosecond laser-induced periodic surface structures on silicon.

PubMed

Xue, Hongyan; Deng, Guoliang; Feng, Guoying; Chen, Lin; Li, Jiaqi; Yang, Chao; Zhou, Shouhuan

2017-09-01

An initial roughness is assumed in the most accepted Sipe-Drude model to analyze laser-induced periodic surface structures (LIPSS). However, the direct experimental observation for the crucial parameters is still lacking. The generation of nanoparticles and low-spatial frequency LIPSS (LSFL) (LIPSS with a periodicity close to laser wavelength) on a silicon surface upon a single pulse and subsequent pulses irradiation, respectively, is observed experimentally. Finite-difference time-domain (FDTD) simulation indicates that the nanoparticles generated with the first pulse enhance the local electric field greatly. Based on the experimental extrapolated parameters, FDTD-η maps have been calculated. The results show that the inhomogeneous energy deposition, which leads to the formation of LSFL, is mainly from the modulation of the nanoparticles with a radius of around 100 nm.

Ethical Implications in Vaccine Pharmacotherapy for Treatment and Prevention of Drug of Abuse Dependence.

PubMed

Carfora, Anna; Cassandro, Paola; Feola, Alessandro; La Sala, Francesco; Petrella, Raffaella; Borriello, Renata

2018-03-01

Different immunotherapeutic approaches are in the pipeline for the treatment of drug dependence. "Drug vaccines" aim to induce the immune system to produce antibodies that bind to drugs and prevent them from inducing rewarding effects in the brain. Drugs of abuse currently being tested using these new approaches are opioids, nicotine, cocaine, and methamphetamine. In human clinical trials, "cocaine and nicotine vaccines" have been shown to induce sufficient antibody levels while producing few side effects. Studies in humans, determining how these vaccines interact in combination with their target drug, are underway. However, although vaccines can become a reasonable treatment option for drugs of abuse, there are several disadvantages that must be considered. These include i) great individual variability in the formation of antibodies, ii) the lack of protection against a structurally dissimilar drug that produces the same effects as the drug of choice, and iii) the lack of an effect on the drug desire that may predispose an addict to relapse. In addition, a comprehensive overview of several crucial ethical issues has not yet been widely discussed in order to have not only a biological approach to immunotherapy of addiction. Overall, immunotherapy offers a range of possible treatment options: the pharmacological treatment of addiction, the treatment of overdoses, the prevention of toxicity to the brain or the heart, and the protection of the fetus during pregnancy. So far, the results obtained from a small-scale experiment using vaccines against cocaine and nicotine suggest that a number of important technical challenges still need to be overcome before such vaccines can be approved for clinical use.

Distinct tissue site-specific requirements of mast cells and complement components C3/C5a receptor in IgG immune complex-induced injury of skin and lung.

PubMed

Baumann, U; Chouchakova, N; Gewecke, B; Köhl, J; Carroll, M C; Schmidt, R E; Gessner, J E

2001-07-15

We induced the passive reverse Arthus reaction to IgG immune complexes (IC) at different tissue sites in mice lacking C3 treated or not with a C5aR-specific antagonist, or in mice lacking mast cells (Kit(W)/Kit(W-v) mice), and compared the inflammatory responses with those in the corresponding wild-type mice. We confirmed that IC inflammation of skin can be mediated largely by mast cells expressing C5aR and FcgammaRIII. In addition, we provided evidence for C3-independent C5aR triggering, which may explain why the cutaneous Arthus reaction develops normally in C3(-/-) mice. Furthermore, some, but not all, of the acute changes associated with the Arthus response in the lung were significantly more intense in normal mice than in C3(-/-) or Kit(W)/Kit(W-v) mice, indicating for C3- and mast cell-dependent and -independent components. Finally, we demonstrated that C3 contributed to the elicitation of neutrophils to alveoli, which corresponded to an increased synthesis of TNF-alpha, macrophage-inflammatory protein-2, and cytokine-induced neutrophil chemoattractant. While mast cells similarly influenced alveolar polymorphonuclear leukocyte influx, the levels of these cytokines remained largely unaffected in mast cell deficiency. Together, the phenotypes of C3(-/-) mice and Kit(W)/Kit(W-v) mice suggest that complement and mast cells have distinct tissue site-specific requirements acting by apparently distinct mechanisms in the initiation of IC inflammation.

Distinct Neuropsychological Mechanisms May Explain Delayed- Versus Rapid-Onset Antidepressant Efficacy

PubMed Central

Stuart, Sarah A; Butler, Paul; Munafò, Marcus R; Nutt, David J; Robinson, Emma SJ

2015-01-01

The biochemical targets for antidepressants are relatively well established, but we lack a clear understanding of how actions at these proteins translate to clinical benefits. This study used a novel rodent assay to investigate how different antidepressant drugs act to modify affective biases that have been implicated in depression. In this bowl-digging task, rats encounter two equal value learning experiences on separate days (one during an affective manipulation and the other during control conditions). This induces an affective bias that is quantified using a preference test in which both digging substrates are presented together and the individual rats’ choices recorded. The assay can be used to measure affective biases associated with learning (when the treatment is given at the time of the experience) or examine the modification of previously acquired biases (when the treatment is administered before the preference test). The rapid-onset antidepressant ketamine, but not the delayed-onset antidepressant, venlafaxine, attenuated the previously acquired FG7142-induced negative bias following systemic administration. Venlafaxine but not ketamine induced a positive bias when administered before learning. We then used local drug infusions and excitotoxic lesions to localize the effects of ketamine to the medial prefrontal cortex and venlafaxine to the amygdala. Using a modified protocol we also showed that positive and negative biases amplified further when the numbers of substrate–reinforcer associations are increased. We propose that this pattern of results could explain the delayed onset of action of venlafaxine and the rapid onset of action but lack of long-term efficacy seen with ketamine. PMID:25740288

Parietal plasticity after training with a complex video game is associated with individual differences in improvements in an untrained working memory task

PubMed Central

Nikolaidis, Aki; Voss, Michelle W.; Lee, Hyunkyu; Vo, Loan T. K.; Kramer, Arthur F.

2014-01-01

Researchers have devoted considerable attention and resources to cognitive training, yet there have been few examinations of the relationship between individual differences in patterns of brain activity during the training task and training benefits on untrained tasks (i.e., transfer). While a predominant hypothesis suggests that training will transfer if there is training-induced plasticity in brain regions important for the untrained task, this theory lacks sufficient empirical support. To address this issue we investigated the relationship between individual differences in training-induced changes in brain activity during a cognitive training videogame, and whether those changes explained individual differences in the resulting changes in performance in untrained tasks. Forty-five young adults trained with a videogame that challenges working memory, attention, and motor control for 15 2-h sessions. Before and after training, all subjects received neuropsychological assessments targeting working memory, attention, and procedural learning to assess transfer. Subjects also underwent pre- and post-functional magnetic resonance imaging (fMRI) scans while they played the training videogame to assess how these patterns of brain activity change in response to training. For regions implicated in working memory, such as the superior parietal lobe (SPL), individual differences in the post-minus-pre changes in activation predicted performance changes in an untrained working memory task. These findings suggest that training-induced plasticity in the functional representation of a training task may play a role in individual differences in transfer. Our data support and extend previous literature that has examined the association between training related cognitive changes and associated changes in underlying neural networks. We discuss the role of individual differences in brain function in training generalizability and make suggestions for future cognitive training research. PMID:24711792

Parietal plasticity after training with a complex video game is associated with individual differences in improvements in an untrained working memory task.

PubMed

Nikolaidis, Aki; Voss, Michelle W; Lee, Hyunkyu; Vo, Loan T K; Kramer, Arthur F

2014-01-01

Researchers have devoted considerable attention and resources to cognitive training, yet there have been few examinations of the relationship between individual differences in patterns of brain activity during the training task and training benefits on untrained tasks (i.e., transfer). While a predominant hypothesis suggests that training will transfer if there is training-induced plasticity in brain regions important for the untrained task, this theory lacks sufficient empirical support. To address this issue we investigated the relationship between individual differences in training-induced changes in brain activity during a cognitive training videogame, and whether those changes explained individual differences in the resulting changes in performance in untrained tasks. Forty-five young adults trained with a videogame that challenges working memory, attention, and motor control for 15 2-h sessions. Before and after training, all subjects received neuropsychological assessments targeting working memory, attention, and procedural learning to assess transfer. Subjects also underwent pre- and post-functional magnetic resonance imaging (fMRI) scans while they played the training videogame to assess how these patterns of brain activity change in response to training. For regions implicated in working memory, such as the superior parietal lobe (SPL), individual differences in the post-minus-pre changes in activation predicted performance changes in an untrained working memory task. These findings suggest that training-induced plasticity in the functional representation of a training task may play a role in individual differences in transfer. Our data support and extend previous literature that has examined the association between training related cognitive changes and associated changes in underlying neural networks. We discuss the role of individual differences in brain function in training generalizability and make suggestions for future cognitive training research.

BCR mediated signal transduction in immature and mature B cells.

PubMed

Koncz, Gábor; Bodor, Csaba; Kövesdi, Dorottya; Gáti, Róbert; Sármay, Gabriella

2002-06-03

Ligation of B cell receptors (BCR) on immature B cells may induce apoptosis, while in mature B cells it stimulates cell activation and growth. The signaling pathway regulating the differential functional response, death or survival of the B cell is not fully characterized. We have tested the intracellular signaling requirement of these processes using B cells isolated from the spleen of irradiated auto-reconstituted (transitional immature B cells) and untreated mice (mature B cells), respectively. We compared the BCR induced intracellular [Ca2+] transient, protein tyrosine phosphorylation and ERK phosphorylation, furthermore, the activation of Elk-1 and CREB transcription factors. The BCR induced rise of intracellular [Ca2+] did not significantly differ in the two populations, only a slight difference in the late phase of the response was observed. Immature B cells responded with a maximum tyrosine phosphorylation to a five times lower dose of anti-IgM compared to the mature population. Most importantly, we have found a significant difference in the tyrosine phosphorylation of the Gab family adaptor proteins, Gab1/2. In contrast to mature B cells, crosslinking of BCR on immature B cells did not induce tyrosine phosphorylation of Gab2, thus the Gab2-organized signal amplification complex could not be produced. Furthermore, we detected a significant difference in the kinetics of BCR induced ERK, Elk-1 and CREB phosphorylation. In immature B cells, ERK was transiently phosphorylated, ceasing after 120 min, while in mature cells, ERK phosphorylation was sustained. Elk-1 and CREB activation was also transient in immature B cells, followed the kinetics of ERK phosphorylation. The lack of sustained Erk1/2 activation suppresses the transcription factors necessary for the proliferation signal. Since ERK is regulated by the phosphorylated Gab1/2, these data demonstrate that BCR triggered phosphorylation and signal amplification of Gab1/2 is a critical step in a life or death decision of B cells.

Letter to the Editor, Response to Commentary "Re-Evaluation of the Big Blue® Mouse Assay of Propiconazole Suggests Lack of Mutagenicity"

EPA Science Inventory

In their commentary titled "Re-Evaluation of the Big Blue® Mouse Assay of Propiconazole Suggests Lack of Mutagenicity", Shane et 01. present an overview of portions of our previously reported work examining the potential for some conazole fungicides to induce increases in mutant ...

The Effects of IGF-1 on Trk Expressing DRG Neurons with HIV-gp120- Induced Neurotoxicity.

PubMed

Li, Hao; Liu, Zhen; Chi, Heng; Bi, Yanwen; Song, Lijun; Liu, Huaxiang

2016-01-01

HIV envelope glycoprotein gp120 is the main protein that causes HIVassociated sensory neuropathy. However, the underlying mechanisms of gp120-induced neurotoxicity are still unclear. There are lack effective treatments for relieving HIV-related neuropathic symptoms caused by gp120-induced neurotoxicity. In the present study, tyrosine kinase receptor (Trk)A, TrkB, and TrkC expression in primary cultured dorsal root ganglion (DRG) neurons with gp120-induced neurotoxicity was investigated. The effects of IGF-1 on distinct Trk-positive DRG neurons with gp120-induced neurotoxicity were also determined. The results showed that gp120 not only dose-dependently induced DRG neuronal apoptosis and inhibited neuronal survival and neurite outgrowth, but also decreased distinct Trk expression levels. IGF-1 rescued DRG neurons from apoptosis and improved neuronal survival of gp120 neurotoxic DRG neurons in vitro. IGF-1 also improved TrkA and TrkB, but not TrkC, expression in gp120 neurotoxic conditions. The effects of IGF-1 could be blocked by preincubation with the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002. These results suggested that gp120 may have a wide range of neurotoxicity on different subpopulations of DRG neurons, while IGF-1 might only relieve some subpopulations of DRG neurons with gp120-induced neurotoxicity. These data provide novel information of mechanisms of gp120 neurotoxicity on primary sensory neurons and the potential therapeutic effects of IGF-1 on gp120-induced neurotoxicity.

Theory and observation of the onset of nonlinear structures due to eigenmode destabilization by fast ions in tokamaks

DOE PAGES

Duarte, V. N.; Berk, H. L.; Gorelenkov, N. N.; ...

2017-12-12

Alfvén waves can induce the ejection of fast ions in different forms in tokamaks. In order to develop predictive capabilities to anticipate the nature of fast ion transport, a methodology is proposed to differentiate the likelihood of energetic-particle-driven instabilities to produce frequency chirping or fixed-frequency oscillations. Furthermore, the proposed method employs numerically calculated eigenstructures and multiple resonance surfaces of a given mode in the presence of energetic ion drag and stochasticity (due to collisions and micro-turbulence). Toroidicity-induced, reversed-shear and beta-induced Alfvén-acoustic eigenmodes are used as examples. Waves measured in experiments are characterized, and compatibility is found between the proposed criterionmore » predictions and the experimental observation or lack of observation of chirping behavior of Alfvénic modes in different tokamaks. It is found that the stochastic diffusion due to micro-turbulence can be the dominant energetic particle detuning mechanism near the resonances in many plasma experiments, and its strength is the key as to whether chirping solutions are likely to arise. We proposed a criterion that constitutes a useful predictive tool in assessing whether the nature of the transport for fast ion losses in fusion devices will be dominated by convective or diffusive processes.« less

Theory and observation of the onset of nonlinear structures due to eigenmode destabilization by fast ions in tokamaks

NASA Astrophysics Data System (ADS)

Duarte, V. N.; Berk, H. L.; Gorelenkov, N. N.; Heidbrink, W. W.; Kramer, G. J.; Nazikian, R.; Pace, D. C.; Podestà, M.; Van Zeeland, M. A.

2017-12-01

Alfvén waves can induce the ejection of fast ions in different forms in tokamaks. In order to develop predictive capabilities to anticipate the nature of fast ion transport, a methodology is proposed to differentiate the likelihood of energetic-particle-driven instabilities to produce frequency chirping or fixed-frequency oscillations. The proposed method employs numerically calculated eigenstructures and multiple resonance surfaces of a given mode in the presence of energetic ion drag and stochasticity (due to collisions and micro-turbulence). Toroidicity-induced, reversed-shear and beta-induced Alfvén-acoustic eigenmodes are used as examples. Waves measured in experiments are characterized, and compatibility is found between the proposed criterion predictions and the experimental observation or lack of observation of chirping behavior of Alfvénic modes in different tokamaks. It is found that the stochastic diffusion due to micro-turbulence can be the dominant energetic particle detuning mechanism near the resonances in many plasma experiments, and its strength is the key as to whether chirping solutions are likely to arise. The proposed criterion constitutes a useful predictive tool in assessing whether the nature of the transport for fast ion losses in fusion devices will be dominated by convective or diffusive processes.

Theory and observation of the onset of nonlinear structures due to eigenmode destabilization by fast ions in tokamaks

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

Duarte, V. N.; Berk, H. L.; Gorelenkov, N. N.

Alfvén waves can induce the ejection of fast ions in different forms in tokamaks. In order to develop predictive capabilities to anticipate the nature of fast ion transport, a methodology is proposed to differentiate the likelihood of energetic-particle-driven instabilities to produce frequency chirping or fixed-frequency oscillations. Furthermore, the proposed method employs numerically calculated eigenstructures and multiple resonance surfaces of a given mode in the presence of energetic ion drag and stochasticity (due to collisions and micro-turbulence). Toroidicity-induced, reversed-shear and beta-induced Alfvén-acoustic eigenmodes are used as examples. Waves measured in experiments are characterized, and compatibility is found between the proposed criterionmore » predictions and the experimental observation or lack of observation of chirping behavior of Alfvénic modes in different tokamaks. It is found that the stochastic diffusion due to micro-turbulence can be the dominant energetic particle detuning mechanism near the resonances in many plasma experiments, and its strength is the key as to whether chirping solutions are likely to arise. We proposed a criterion that constitutes a useful predictive tool in assessing whether the nature of the transport for fast ion losses in fusion devices will be dominated by convective or diffusive processes.« less

LH responses to single doses of exogenous GnRH by social Mashona mole-rats: a continuum of socially induced infertility in the family Bathyergidae.

PubMed Central

Bennett, N C; Faulkes, C G; Spinks, A C

1997-01-01

The Mashona mole-rat, Cryptomys darlingi, exhibits an extreme reproductive division of labour. Reproduction in the colony is restricted to a single breeding pair. The non-reproductive male and female colony members are restrained from sexual activity by being familiar and related to one another and the reproductive animals. Circulating basal concentrations of luteinizing hormone (LH) as well as LH levels measured in response to a single exogenous gonadotropin releasing hormone (GnRH) challenge are not significantly different between the reproductive and non-reproductive groups of either sex. Socially induced infertility in both non-reproductive males and females does not result from a reduced pituitary secretion of LH or decreased sensitivity to hypothalamic GnRH, but rather appears to result from an inhibition of reproductive behaviour in these obligate outbreeders. The African mole-rats exhibit a continuum of socially induced infertility with differing social species inhabiting regions of varying degrees of aridity. In this continuum a transition from a predominantly behavioural repression in a social mesic-adapted species through to complete physiological suppression lacking incest avoidance in an arid-adapted eusocial species occurs in this endemic African family of rodents. PMID:9263467

Effect of Vitamin E on Oxaliplatin-induced Peripheral Neuropathy Prevention: A Randomized Controlled Trial.

PubMed

Salehi, Zeinab; Roayaei, Mahnaz

2015-01-01

Peripheral neuropathy is one of the most important limitations of oxaliplatin base regimen, which is the standard for the treatment of colorectal cancer. Evidence has shown that Vitamin E may be protective in chemotherapy-induced peripheral neuropathy. The aim of this study is to evaluate the effect of Vitamin E administration on prevention of oxaliplatin-induced peripheral neuropathy in patients with colorectal cancer. This was a prospective randomized, controlled clinical trial. Patients with colorectal cancer and scheduled to receive oxaliplatin-based regimens were enrolled in this study. Enrolled patients were randomized into two groups. The first group received Vitamin E at a dose of 400 mg daily and the second group observed, until after the sixth course of the oxaliplatin regimen. For oxaliplatin-induced peripheral neuropathy assessment, we used the symptom experience diary questionnaire that completed at baseline and after the sixth course of chemotherapy. Only patients with a score of zero at baseline were eligible for this study. Thirty-two patients were randomized to the Vitamin E group and 33 to the control group. There was no difference in the mean peripheral neuropathy score changes (after - before) between two groups, after sixth course of the oxaliplatin base regimen (mean difference [after - before] of Vitamin E group = 6.37 ± 2.85, control group = 6.57 ± 2.94; P = 0.78). Peripheral neuropathy scores were significantly increased after intervention compared with a base line in each group (P < 0.001). The results from this current trial demonstrate a lack of benefit for Vitamin E in preventing oxaliplatin-induced peripheral neuropathy.

Cocaine induced cortical microischemia in the rodent brain: Clinical implications

PubMed Central

Ren, Hugang; Du, Congwu; Yuan, Zhijia; Park, Ki; Volkow, Nora D.; Pan, Yingtian

2014-01-01

Cocaine-induced stroke is among the most serious medical complications associated with its abuse. However the extent to which acute cocaine may induce silent microischemia predisposing the cerebral tissue to neurotoxicity has not been investigated; in part, because of limitations of current neuroimaging tools, i.e., lack of high spatiotemporal resolution and sensitivity to simultaneously measure cerebral blood flow (CBF) in vessels of different calibers (including capillaries) quantitatively and over a large field of view. Here we combine ultrahigh-resolution optical coherence tomography to enable tracker-free 3D microvascular angiography (μOCA) and a new phase-intensity-mapping algorithm to enhance the sensitivity of 3D optical Doppler tomography (μODT) for simultaneous capillary CBF quantization. We apply the technique to study the responses of cerebral microvascular networks to single and repeated cocaine administration in the mouse somatosensory cortex. We show that within 2–3 minutes after cocaine administration CBF markedly decreased (e.g., ~70%) but the magnitude and recovery differed for the various types of vessels; arterioles had the fastest recovery (~5min), capillaries varied drastically (from 4–20min) and venules showed relatively slower recovery (~12min). More importantly, we showed that cocaine interrupted CBF in some arteriolar branches for over 45min and this effect was exacerbated with repeated cocaine administration. These results provide evidence that cocaine doses within the range administered by drug abusers induces cerebral microischemia and that these effects are exacerbated with repeated use. Thus cocaine-induced microischemia is likely to be a contributor to its neurotoxic effects. PMID:22124273

Absence of opioid stress-induced analgesia in mice lacking beta-endorphin by site-directed mutagenesis.

PubMed Central

Rubinstein, M; Mogil, J S; Japón, M; Chan, E C; Allen, R G; Low, M J

1996-01-01

A physiological role for beta-endorphin in endogenous pain inhibition was investigated by targeted mutagenesis of the proopiomelanocortin gene in mouse embryonic stem cells. The tyrosine codon at position 179 of the proopiomelanocortin gene was converted to a premature translational stop codon. The resulting transgenic mice display no overt developmental or behavioral alterations and have a normally functioning hypothalamic-pituitary-adrenal axis. Homozygous transgenic mice with a selective deficiency of beta-endorphin exhibit normal analgesia in response to morphine, indicating the presence of functional mu-opiate receptors. However, these mice lack the opioid (naloxone reversible) analgesia induced by mild swim stress. Mutant mice also display significantly greater nonopioid analgesia in response to cold water swim stress compared with controls and display paradoxical naloxone-induced analgesia. These changes may reflect compensatory upregulation of alternative pain inhibitory mechanisms. Images Fig. 1 Fig. 2 PMID:8633004

Spatiotemporal dynamics of DNA repair proteins following laser microbeam induced DNA damage – When is a DSB not a DSB?☆

PubMed Central

Reynolds, Pamela; Botchway, Stanley W.; Parker, Anthony W.; O’Neill, Peter

2013-01-01

The formation of DNA lesions poses a constant threat to cellular stability. Repair of endogenously and exogenously produced lesions has therefore been extensively studied, although the spatiotemporal dynamics of the repair processes has yet to be fully understood. One of the most recent advances to study the kinetics of DNA repair has been the development of laser microbeams to induce and visualize recruitment and loss of repair proteins to base damage in live mammalian cells. However, a number of studies have produced contradictory results that are likely caused by the different laser systems used reflecting in part the wavelength dependence of the damage induced. Additionally, the repair kinetics of laser microbeam induced DNA lesions have generally lacked consideration of the structural and chemical complexity of the DNA damage sites, which are known to greatly influence their reparability. In this review, we highlight the key considerations when embarking on laser microbeam experiments and interpreting the real time data from laser microbeam irradiations. We compare the repair kinetics from live cell imaging with biochemical and direct quantitative cellular measurements for DNA repair. PMID:23688615

A comparative study of induced abortions before and after legalization of abortions.

PubMed

Malhotra, S; Devi, P K

1979-06-01

Abortion was legalized in many states in India in April 1972. This study deals with 2 groups of patients admitted to P.G.I., Chadigarh, with problems of induced septic abortion. Group 1 consisted of 88 patients admitted during the 2 1/2 year period from 1 July 1969 to 31 December 1971, before the legalization of abortion. Group 2 consists of 133 patients admitted during the 2 1/2 year period from 1 July 1973 to 31 December 1975. 1 year after the new abortion law had been in force. Not only has there been an increase in the total number of patients, there has been an increase in the severity of infection. Evidently, the liberalization of the law has encouraged more patients to seek abortions and has encouraged more doctors, lacking proper qualifications, to perform them. The morbidity and mortality with induced septic abortion can only be reduced if enough public propaganda makes the people especially in rural areas conscious of the hazards of induced abortion by "dais" and unqualified personnel, simultaneously making them aware of the provision of law and facilities available at different centers. Meanwhile, the law against unskilled and untrained personnel should be rigorously enforced.

Catalase-peroxidase activity has no influence on virulence in a murine model of tuberculosis.

PubMed

Cardona, Pere Joan; Gordillo, Sergi; Amat, Isabel; Díaz, Jorge; Lonca, Joan; Vilaplana, Cristina; Pallarés, Angeles; Llatjós, Roger; Ariza, Aurelio; Ausina, Vicenç

2003-01-01

The capacity to generate a chronic and persistent infection in the experimental murine model of tuberculosis induced aerogenically by a low-dose inoculum was determined in eight isoniazid-resistant clinical strains of Mycobacterium tuberculosis showing different catalase-peroxidase (C-P) activities. Determination of bacillary concentration in lung and spleen and the percentage of pulmonary parenchyma occupied by granulomas were monitored. Data showed no relation between the lack of C-P activity and the ability to develop a persistent infection, highlighting the potential of C-P negative strains to spread through the community.

A chloroplast lipoxygenase is required for wound-induced jasmonic acid accumulation in Arabidopsis.

PubMed Central

Bell, E; Creelman, R A; Mullet, J E

1995-01-01

Plant lipoxygenases are thought to be involved in the biosynthesis of lipid-derived signaling molecules. The potential involvement of a specific Arabidopsis thaliana lipoxygenase isozyme, LOX2, in the biosynthesis of the plant growth regulators jasmonic acid (JA) and abscisic acid was investigated. Our characterization of LOX2 indicates that the protein is targeted to chloroplasts. The physiological role of this chloroplast lipoxygenase was analyzed in transgenic plants where cosuppression reduced LOX2 accumulation. The reduction in LOX2 levels caused no obvious changes in plant growth or in the accumulation of abscisic acid. However, the wound-induced accumulation of JA observed in control plants was absent in leaves of transgenic plants that lacked LOX2. Thus, LOX2 is required for the wound-induced synthesis of the plant growth regulator JA in leaves. We also examined the expression of a wound- and JA-inducible Arabidopsis gene, vsp, in transgenic and control plants. Leaves of transgenic plants lacking LOX2 accumulated less vsp mRNA than did control leaves in response to wounding. This result suggests that wound-induced JA (or some other LOX2-requiring component of the wound response pathway) is involved in the wound-induced regulation of this gene. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 PMID:7567995

Immune activation by medium-chain triglyceride-containing lipid emulsions is not modulated by n-3 lipids or toll-like receptor 4.

PubMed

Olthof, Evelyn D; Gülich, Alexandra F; Renne, Mike F; Landman, Sija; Joosten, Leo A B; Roelofs, Hennie M J; Wanten, Geert J A

2015-10-01

Saturated medium-chain triglycerides (MCT) as part of the parenteral lipid regimen (50% MCT and 50% long chain triglycerides (LCT)) activate the immune system in vitro. Fish oil (FO)-derived n-3 fatty acids (FA) inhibit saturated FA-induced immune activation via a toll-like receptor (TLR)-4 mediated mechanism. We hypothesized that effects of parenteral MCTs on immune cells involve TLR-4 signaling and that these effects are modulated by n-3 FA that are present in FO. To test this hypothesis we assessed effects of addition of various commercially available mixed parenteral lipid emulsions, n-3 FA and of TLR-4 inhibition on MCT-induced human immune cell activation by evaluation of the expression of leukocyte membrane activation markers and reactive oxygen species (ROS) production. All MCT-containing lipid emulsions activated leukocytes by inducing changes in expression of membrane markers and stimulus induced ROS production, whereas MCT-free lipid emulsions lacked this effect. Moreover, addition of n-3 FA to LCT/MCT did not prevent MCT-induced immune activation. TLR-4 inhibitors did not distinctly modulate MCT-induced changes in immune function. Taken together, these findings suggest that leukocyte activation by parenteral MCTs does not involve TLR-4 signaling and is not modulated by n-3 FA in FO-, but is exerted via different signaling pathways. Copyright © 2015 Elsevier Ltd. All rights reserved.

Abnormal experimentally- and behaviorally-induced LTP-like plasticity in focal hand dystonia.

PubMed

Belvisi, Daniele; Suppa, Antonio; Marsili, Luca; Di Stasio, Flavio; Parvez, Ahmad Khandker; Agostino, Rocco; Fabbrini, Giovanni; Berardelli, Alfredo

2013-02-01

Idiopathic focal hand dystonia (FHD) arises from abnormal plasticity in the primary motor cortex (M1) possibly reflecting abnormal sensori-motor integration processes. In this transcranial magnetic stimulation (TMS) study in FHD, we evaluated changes in motor evoked potentials (MEPs) after intermittent theta burst stimulation (iTBS) and paired associative stimulation (PAS), techniques that elicit different forms of experimentally-induced long-term potentiation (LTP)-like plasticity in M1. We also examined behaviorally-induced LTP-like plasticity as reflected by early motor learning of a simple motor task. We studied 14 patients with FHD and 14 healthy subjects. MEPs were recorded before and after iTBS and PAS at the 25 ms interstimulus interval (PAS(25)) in separate sessions. Subjects did a simple motor task entailing repetitive index finger abductions. To measure early motor learning we tested practice-related improvement in peak velocity and peak acceleration. In FHD patients iTBS failed to elicit the expected MEP changes and PAS(25) induced abnormally increased MEPs in target and non-target muscles. In the experiment testing early motor learning, patients lacked the expected practice-related changes in kinematic variables. In FHD, the degree of early motor learning correlated with patients' clinical features. We conclude that experimentally-induced (iTBS and PAS) and behaviorally-induced LTP-like plasticity are both altered in FHD. Copyright © 2012 Elsevier Inc. All rights reserved.

The availability of hydrogeologic data associated with areas identified by the US Geological Survey as experiencing potentially induced seismicity resulting from subsurface injection

NASA Astrophysics Data System (ADS)

Barnes, Caitlin; Halihan, Todd

2018-05-01

A critical need exists for site-specific hydrogeologic data in order to determine potential hazards of induced seismicity and to manage risk. By 2015, the United States Geological Survey (USGS) had identified 17 locations in the USA that are experiencing an increase in seismicity, which may be potentially induced through industrial subsurface injection. These locations span across seven states, which vary in geological setting, industrial exposure and seismic history. Comparing the research across the 17 locations revealed patterns for addressing induced seismicity concerns, despite the differences between geographical locations. Most induced seismicity studies evaluate geologic structure and seismic data from areas experiencing changes in seismic activity levels, but the inherent triggering mechanism is the transmission of hydraulic pressure pulses. This research conducted a systematic review of whether data are available in these locations to generate accurate hydrogeologic predictions, which could aid in managing seismicity. After analyzing peer-reviewed research within the 17 locations, this research confirms a lack of site-specific hydrogeologic data availability for at-risk areas. Commonly, formation geology data are available for these sites, but hydraulic parameters for the seismically active injection and basement zones are not available to researchers conducting peer-reviewed research. Obtaining hydrogeologic data would lead to better risk management for injection areas and provide additional scientific evidential support for determining a potentially induced seismic area.

Nuclear receptor ERR alpha and coactivator PGC-1 beta are effectors of IFN-gamma-induced host defense.

PubMed

Sonoda, Junichiro; Laganière, Josée; Mehl, Isaac R; Barish, Grant D; Chong, Ling-Wa; Li, Xiangli; Scheffler, Immo E; Mock, Dennis C; Bataille, Alain R; Robert, Francois; Lee, Chih-Hao; Giguère, Vincent; Evans, Ronald M

2007-08-01

Macrophage activation by the proinflammatory cytokine interferon-gamma (IFN-gamma) is a critical component of the host innate response to bacterial pathogenesis. However, the precise nature of the IFN-gamma-induced activation pathway is not known. Here we show using genome-wide expression and chromatin-binding profiling that IFN-gamma induces the expression of many nuclear genes encoding mitochondrial respiratory chain machinery via activation of the nuclear receptor ERR alpha (estrogen-related receptor alpha, NR3B1). Studies with macrophages lacking ERR alpha demonstrate that it is required for induction of mitochondrial reactive oxygen species (ROS) production and efficient clearance of Listeria monocytogenes (LM) in response to IFN-gamma. As a result, mice lacking ERR alpha are susceptible to LM infection, a phenotype that is localized to bone marrow-derived cells. Furthermore, we found that IFN-gamma-induced activation of ERR alpha depends on coactivator PGC-1 beta (peroxisome proliferator-activated receptor gamma coactivator-1 beta), which appears to be a direct target for the IFN-gamma/STAT-1 signaling cascade. Thus, ERR alpha and PGC-1 beta act together as a key effector of IFN-gamma-induced mitochondrial ROS production and host defense.

Optimal prevention of seizures induced by high-dose busulfan.

PubMed

Eberly, Andrea L; Anderson, Gail D; Bubalo, Joseph S; McCune, Jeannine S

2008-12-01

High-dose busulfan is frequently used in a variety of conditioning regimens for hematopoietic cell transplantation. In this setting, busulfan has marked neurotoxicity, specifically causing seizures that generally are tonic-clonic in character. Phenytoin has been the preferred drug to treat busulfan-induced seizures, but this practice should be reexamined in light of newer antiepileptic drugs being preferentially used by neurologists. Characteristics of ideal seizure prophylaxis include lack of overlapping toxicity with the conditioning regimen, lack of interference with engraftment of donor cells, and minimal potential for pharmacokinetic drug interactions. Based on these criteria, phenytoin is suboptimal due to possible toxicities and is especially ill suited because of its ability to induce busulfan metabolism. It is postulated that this induction adversely affects efforts to update methods for targeting busulfan doses to individual patients, based on recent developments in the understanding of the pharmacogenomics of busulfan metabolism. The existing clinical data support the use of benzodiazepines, most notably clonazepam and lorazepam, to prevent busulfan-induced seizures. The second-generation antiepileptic drug levetiracetam possesses the characteristics of optimal prophylaxis for busulfan-induced seizures, and early data of its efficacy are promising, although further study is needed.

Genetic Epidemiology of Cigarette Smoke–Induced Lung Disease

PubMed Central

2012-01-01

Chronic obstructive pulmonary disease (COPD) and lung cancer represent two diseases that share a strong risk factor in smoking, and COPD increases risk of lung cancer even after adjusting for the effects of smoking. These diseases not only occur jointly within an individual but also there is evidence of shared occurrence within families. Understanding the genetic contributions to these diseases, both individually and jointly, is needed to identify the highest risk group for screening and targeted prevention, as well as aiding in the development of targeted treatments. The chromosomal regions that have been identified as being associated either jointly or independently with lung cancer, COPD, nicotine addiction, and lung function are presented. Studies jointly measuring genetic variation in lung cancer and COPD have been limited by the lack of detailed COPD diagnosis and severity data in lung cancer populations, the lack of lung cancer–specific phenotypes (histology and tumor markers) in COPD populations, and the lack of inclusion of minorities. African Americans, who smoke fewer cigarettes per day and have different linkage disequilibrium and disease patterns than whites, and Asians, also with different patterns of exposure to lung carcinogens and linkage patterns, will provide invaluable information to better understand shared and independent genetic contributions to lung cancer and COPD to more fully define the highest risk group of individuals who will most benefit from screening and to develop molecular signatures to aid in targeted treatment and prevention efforts. PMID:22550237

LACK OF EXPRESSION OF EGF AND TGF-ALPHA IN THE FETAL MOUSE ALTERS FORMATION OF PROSTATIC EPITHELIAL BUDS AND INFLUENCES THE RESPONSE TO TCDD

EPA Science Inventory

Lack of Expression of EGF and TGF in the Fetal Mouse Alters Formation of Prostatic Epithelial Buds and Responsiveness to TCDD-Induced Impairment of Prostatic Bud Formation.

Barbara D. Abbott, Tien-Min Lin, Nathan T. Rasmussen, Robert W. Moore,
Ralph M. Albrecht, Judi...

Fenofibrate, but not ezetimibe, prevents fatty liver disease in mice lacking phosphatidylethanolamine N-methyltransferase.

PubMed

van der Veen, Jelske N; Lingrell, Susanne; Gao, Xia; Takawale, Abhijit; Kassiri, Zamaneh; Vance, Dennis E; Jacobs, René L

2017-04-01

Mice lacking phosphatidylethanolamine N -methyltransferase (PEMT) are protected from high-fat diet (HFD)-induced obesity and insulin resistance. However, these mice develop severe nonalcoholic fatty liver disease (NAFLD) when fed the HFD, which is mainly due to inadequate secretion of VLDL particles. Our aim was to prevent NAFLD development in mice lacking PEMT. We treated Pemt -/- mice with either ezetimibe or fenofibrate to see if either could ameliorate liver disease in these mice. Ezetimibe treatment did not reduce fat accumulation in Pemt -/- livers, nor did it reduce markers for hepatic inflammation or fibrosis. Fenofibrate, conversely, completely prevented the development of NAFLD in Pemt -/- mice: hepatic lipid levels, as well as markers of endoplasmic reticulum stress, inflammation, and fibrosis, in fenofibrate-treated Pemt -/- mice were similar to those in Pemt +/+ mice. Importantly, Pemt -/- mice were still protected against HFD-induced obesity and insulin resistance. Moreover, fenofibrate partially reversed hepatic steatosis and fibrosis in Pemt -/- mice when treatment was initiated after NAFLD had already been established. Increasing hepatic fatty acid oxidation can compensate for the lower VLDL-triacylglycerol secretion rate and prevent/reverse fatty liver disease in mice lacking PEMT. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

Fenofibrate, but not ezetimibe, prevents fatty liver disease in mice lacking phosphatidylethanolamine N-methyltransferase[S

PubMed Central

van der Veen, Jelske N.; Lingrell, Susanne; Gao, Xia; Takawale, Abhijit; Kassiri, Zamaneh; Vance, Dennis E.; Jacobs, René L.

2017-01-01

Mice lacking phosphatidylethanolamine N-methyltransferase (PEMT) are protected from high-fat diet (HFD)-induced obesity and insulin resistance. However, these mice develop severe nonalcoholic fatty liver disease (NAFLD) when fed the HFD, which is mainly due to inadequate secretion of VLDL particles. Our aim was to prevent NAFLD development in mice lacking PEMT. We treated Pemt−/− mice with either ezetimibe or fenofibrate to see if either could ameliorate liver disease in these mice. Ezetimibe treatment did not reduce fat accumulation in Pemt−/− livers, nor did it reduce markers for hepatic inflammation or fibrosis. Fenofibrate, conversely, completely prevented the development of NAFLD in Pemt−/− mice: hepatic lipid levels, as well as markers of endoplasmic reticulum stress, inflammation, and fibrosis, in fenofibrate-treated Pemt−/− mice were similar to those in Pemt+/+ mice. Importantly, Pemt−/− mice were still protected against HFD-induced obesity and insulin resistance. Moreover, fenofibrate partially reversed hepatic steatosis and fibrosis in Pemt−/− mice when treatment was initiated after NAFLD had already been established. Increasing hepatic fatty acid oxidation can compensate for the lower VLDL-triacylglycerol secretion rate and prevent/reverse fatty liver disease in mice lacking PEMT. PMID:28159867

Pancreatic Effects of a Bruton's Tyrosine Kinase Small-molecule Inhibitor in Rats Are Strain-dependent.

PubMed

Bhaskaran, Manoj; Cornwell, Paul D; Sorden, Steven D; Elwell, Michael R; Russell, Natalie R; Pritt, Michael L; Vahle, John L

2018-01-01

Inhibitors of Bruton's tyrosine kinase (BTK) are under development as potential therapies for various autoimmune diseases. In repeat-dose toxicity studies, small-molecule BTK inhibitors (BTKi) have been reported to cause a constellation of histologic effects at the pancreatic endocrine-exocrine interface in male rats; however, similar findings were not reported in other species. Since the BTKi-induced pancreatic effect is morphologically similar to well-documented spontaneous changes (predominantly characterized by insular/peri-insular hemorrhage, pigment deposition, chronic inflammation, and fibrosis) that are known to vary by rat strain, we investigated potential strain-dependent differences in the pancreatic effects of a small-molecule BTKi, LY3337641. Following 13 weeks of LY3337641 treatment, Crl:CD(SD) rats were most sensitive, Crl:WI(Han) rats were of intermediate sensitivity, and Hsd:SD rats were least sensitive. These strain differences appear to be related to differences in rate of weight gain across strains and sexes; however, a definitive mechanism was not determined. This study demonstrated that BTKi-induced pancreatic effects were highly dependent on rat strain and correlated with differences in the incidence and severity of the spontaneous background change. When considered with the lack of pancreas effects in nonrat species, these changes in rats are unlikely predictive of similar changes in humans administered a BTK inhibitor.

Social rank-associated stress vulnerability predisposes individuals to cocaine attraction.

PubMed

Yanovich, Chen; Kirby, Michael L; Michaelevski, Izhak; Yadid, Gal; Pinhasov, Albert

2018-01-29

Studies of personality have suggested that dissimilarities in ability to cope with stressful situations results in differing tendency to develop addictive behaviors. The present study used selectively bred stress-resilient, socially-dominant (Dom) and stress-vulnerable, socially-submissive (Sub) mice to investigate the interaction between environmental stress and inbred predisposition to develop addictive behavior to cocaine. In a Conditioned Place Preference (CPP) paradigm using cocaine, Sub mice displayed an aversion to drug, whereas Dom mice displayed drug attraction. Following a 4-week regimen of Chronic Mild Stress (CMS), Sub mice in CPP displayed a marked increase (>400%) in cocaine attraction, whereas Dom mice did not differ in attraction from their non-stressed state. Examination of hippocampal gene expression revealed in Sub mice, exposure to external stimuli, stress or cocaine, increased CRH expression (>100%), which was evoked in Dom mice only by cocaine exposure. Further, stress-induced decreases in DRD1 (>60%) and DRD2 (>50%) expression in Sub mice differed markedly from a complete lack of change in Dom mice. From our findings, we propose that social stratification dictates vulnerability to stress-induced attraction that may lead to addiction via differential regulation of hippocampal response to dopaminergic input, which in turn may influence differing tendency to develop addictive behaviors.

Lack of differences in radiation-induced immunogenicity parameters between HPV-positive and HPV-negative human HNSCC cell lines.

PubMed

Schneider, Karolin; Bol, Vanesa; Grégoire, Vincent

2017-09-01

Clinical studies indicate that patients with HPV/p16-associated head & neck squamous cell carcinoma (HNSCC) represent a subgroup with a better prognosis and improved response to conventional radiotherapy. Involvement of immune-based factors has been hypothesized. In the present study, we investigated radiation-induced differences in release of damage associated molecular patterns (DAMPs), cytokines and activation of dendritic cells (DCs) in HPV-positive and negative HNSCC cancer cell lines. Calreticulin (CRT) exposure was detected on cancer cell surface. ATP, HMGB1 and cytokines were measured in culture supernatants. Maturation marker CD83 surface exposure was determined on DCs after co-incubation with irradiated tumor cells. There was no increase in DAMPs and cytokine profiles after radiation treatment and no difference between HPV+ and HPV- cell lines. The HPV/p16-positive SCC90 cells showed a trend for increased total CRT, HMGB1, and number of cytokines compared to all other cell lines. None of the irradiated cancer cell lines could affect DC maturation. Radiation treatment did not increase immunogenicity of HNSCC cell lines assessed by membrane CRT, ATP, HMGB1, cytokines production, and by activation of immature DCs. There was no difference between HPV-positive and HPV-negative cell lines. Copyright © 2017 Elsevier B.V. All rights reserved.

Virus-Induced Gene Silencing of the Eggplant Chalcone Synthase Gene during Fruit Ripening Modifies Epidermal Cells and Gravitropism.

PubMed

Wang, Cuicui; Fu, Daqi

2018-03-21

Eggplant ( Solanum melongena L.) fruits accumulate flavonoids in their cuticle and epidermal cells during ripening. Although many mutants available in model plant species, such as Arabidopsis thaliana and Medicago truncatula, are enabling the intricacies of flavonoid-related physiology to be deduced, the mechanisms whereby flavonoids influence eggplant fruit physiology are unknown. Virus-induced gene silencing (VIGS) is a reliable tool for the study of flavonoid function in fruit, and in this study, we successfully applied this technique to downregulate S. melongena chalcone synthase gene ( SmCHS) expression during eggplant fruit ripening. In addition to the expected change in fruit color attributable to a lack of anthocyanins, several other modifications, including differences in epidermal cell size and shape, were observed in the different sectors. We also found that silencing of CHS gene expression was associated with a negative gravitropic response in eggplant fruits. These observations indicate that epidermal cell expansion during ripening is dependent upon CHS expression and that there may be a relationship between CHS expression and gravitropism during eggplant fruit ripening.

Balancing Demands and Resources in Sport: Adaptation and Validation of the Demand-Induced Strain Compensation Questionnaire for Use in Sport.

PubMed

Balk, Yannick A; De Jonge, Jan; Oerlemans, Wido G M; Geurts, Sabine A E; Fletcher, David; Dormann, Christian

2018-06-01

Too high demands, combined with a lack of resources, are often detrimental to athletic health and well-being. However, a valid and reliable instrument to investigate different dimensions of demands and resources in sport is currently unavailable. Therefore, the present study examines the psychometric properties of an existing and well-validated survey instrument on demands and resources at task-level that was adapted to sport. This instrument, the Demand-Induced Strain Compensation Questionnaire for Sport (DISQ-SPORT), was empirically tested among 1,101 athletes (416 females and 685 males) from a variety of sports and in different languages. Results supported the proposed six-factor structure of the instrument, consisting of physical, cognitive, and emotional demands and resources. Internal consistencies of all subscales were satisfactory and the instrument was invariant across type of sport, competitive level and language. Continued evaluation of the psychometric properties of the DISQ-SPORT, especially in terms of content validity and test-retest stability, is nevertheless warranted. Theoretical and practical implications as well as areas for future research are discussed.

TRPA1 and TRPV1 are required for lidocaine-evoked calcium influx and neuropeptide release but not cytotoxicity in mouse sensory neurons.

PubMed

Eberhardt, Mirjam; Stueber, Thomas; de la Roche, Jeanne; Herzog, Christine; Leffler, Andreas; Reeh, Peter W; Kistner, Katrin

2017-01-01

Local anaesthetics (LA) reduce neuronal excitability by inhibiting voltage-gated Na+ channels. When applied at high concentrations in the direct vicinity of nerves, LAs can also induce relevant irritation and neurotoxicity via mechanisms involving an increase of intracellular Ca2+. In the present study we explored the role of the Ca2+-permeable ion channels TRPA1 and TRPV1 for lidocaine-induced Ca2+-influx, neuropeptide release and neurotoxicity in mouse sensory neurons. Cultured dorsal root ganglion (DRG) neurons from wildtype and mutant mice lacking TRPV1, TRPA1 or both channels were explored by means of calcium imaging, whole-cell patch clamp recordings and trypan blue staining for cell death. Release of calcitonin gene-related peptide (CGRP) from isolated mouse peripheral nerves was determined with ELISA. Lidocaine up to 10 mM induced a concentration-dependent reversible increase in intracellular Ca2+ in DRG neurons from wildtype and mutant mice lacking one of the two receptors, but not in neurons lacking both TRPA1 and TRPV1. 30 mM lidocaine also released Ca2+ from intracellular stores, presumably from the endoplasmic reticulum. While 10 mM lidocaine evoked an axonal CGRP release requiring expression of either TRPA1 or TRPV1, CGRP release induced by 30 mM lidocaine again mobilized internal Ca2+ stores. Lidocaine-evoked cell death required neither TRPV1 nor TRPA1. Depending on the concentration, lidocaine employs TRPV1, TRPA1 and intracellular Ca2+ stores to induce a Ca2+-dependent release of the neuropeptide CGRP. Lidocaine-evoked cell death does not seem to require Ca2+ influx through TRPV1 or TRPV1.

TRPA1 and TRPV1 are required for lidocaine-evoked calcium influx and neuropeptide release but not cytotoxicity in mouse sensory neurons

PubMed Central

Eberhardt, Mirjam; Stueber, Thomas; de la Roche, Jeanne; Herzog, Christine; Leffler, Andreas; Reeh, Peter W.

2017-01-01

Background Local anaesthetics (LA) reduce neuronal excitability by inhibiting voltage-gated Na+ channels. When applied at high concentrations in the direct vicinity of nerves, LAs can also induce relevant irritation and neurotoxicity via mechanisms involving an increase of intracellular Ca2+. In the present study we explored the role of the Ca2+-permeable ion channels TRPA1 and TRPV1 for lidocaine-induced Ca2+-influx, neuropeptide release and neurotoxicity in mouse sensory neurons. Methods Cultured dorsal root ganglion (DRG) neurons from wildtype and mutant mice lacking TRPV1, TRPA1 or both channels were explored by means of calcium imaging, whole-cell patch clamp recordings and trypan blue staining for cell death. Release of calcitonin gene-related peptide (CGRP) from isolated mouse peripheral nerves was determined with ELISA. Results Lidocaine up to 10 mM induced a concentration-dependent reversible increase in intracellular Ca2+ in DRG neurons from wildtype and mutant mice lacking one of the two receptors, but not in neurons lacking both TRPA1 and TRPV1. 30 mM lidocaine also released Ca2+ from intracellular stores, presumably from the endoplasmic reticulum. While 10 mM lidocaine evoked an axonal CGRP release requiring expression of either TRPA1 or TRPV1, CGRP release induced by 30 mM lidocaine again mobilized internal Ca2+ stores. Lidocaine-evoked cell death required neither TRPV1 nor TRPA1. Summary Depending on the concentration, lidocaine employs TRPV1, TRPA1 and intracellular Ca2+ stores to induce a Ca2+-dependent release of the neuropeptide CGRP. Lidocaine-evoked cell death does not seem to require Ca2+ influx through TRPV1 or TRPV1. PMID:29141003

High-affinity α4β2 nicotinic receptors mediate the impairing effects of acute nicotine on contextual fear extinction.

PubMed

Kutlu, Munir Gunes; Holliday, Erica; Gould, Thomas J

2016-02-01

Previously, studies from our lab have shown that while acute nicotine administered prior to training and testing enhances contextual fear conditioning, acute nicotine injections prior to extinction sessions impair extinction of contextual fear. Although there is also strong evidence showing that the acute nicotine's enhancing effects on contextual fear conditioning require high-affinity α4β2 nicotinic acetylcholine receptors (nAChRs), it is unknown which nAChR subtypes are involved in the acute nicotine-induced impairment of contextual fear extinction. In this study, we investigated the effects of acute nicotine administration on contextual fear extinction in knock-out (KO) mice lacking α4, β2 or α7 subtypes of nAChRs and their wild-type (WT) littermates. Both KO and WT mice were first trained and tested for contextual fear conditioning and received a daily contextual extinction session for 4 days. Subjects received intraperitoneal injections of nicotine (0.18 mg/kg) or saline 2-4 min prior to each extinction session. Our results showed that the mice that lack α4 and β2 subtypes of nAChRs showed normal contextual fear extinction but not the acute nicotine-induced impairment while the mice that lack the α7 subtype showed both normal contextual extinction and nicotine-induced impairment of contextual extinction. In addition, control experiments showed that acute nicotine-induced impairment of contextual fear extinction persisted when nicotine administration was ceased and repeated acute nicotine administrations alone did not induce freezing behavior in the absence of context-shock learning. These results clearly demonstrate that high-affinity α4β2 nAChRs are necessary for the effects of acute nicotine on contextual fear extinction. Copyright © 2015 Elsevier Inc. All rights reserved.

High-affinity α4β2 nicotinic receptors mediate the impairing effects of acute nicotine on contextual fear extinction

PubMed Central

Kutlu, Munir Gunes; Holliday, Erica; Gould, Thomas J.

2015-01-01

Previously, studies from our lab have shown that while acute nicotine administered prior to training and testing enhances contextual fear conditioning, acute nicotine injections prior to extinction sessions impair extinction of contextual fear. Although there is also strong evidence showing that the acute nicotine’s enhancing effects on contextual fear conditioning require high-affinity α4β2 nicotinic acetylcholine receptors (nAChRs), it is unknown which nAChR subtypes are involved in the acute nicotine-induced impairment of contextual fear extinction. In this study, we investigated the effects of acute nicotine administration on contextual fear extinction in knock-out (KO) mice lacking α4, β2 or α7 subtypes of nAChRs and their wild-type (WT) littermates. Both KO and WT mice were first trained and tested for contextual fear conditioning and received a daily contextual extinction session for 4 days. Subjects received intraperitoneal injections of nicotine (0.18 mg/kg) or saline 2–4 mins prior to each extinction session. Our results showed that the that mice lack α4 and β2 subtypes of nAChRs showed normal contextual fear extinction but not the acute nicotine-induced impairment while the mice that lack the α7 subtype showed both normal contextual extinction and nicotine-induced impairment of contextual extinction. In addition, control experiments showed that acute nicotine-induced impairment of contextual fear extinction persisted when nicotine administration was ceased and repeated acute nicotine administrations alone did not induce freezing behavior in the absence of context-shock learning. These results clearly demonstrate that high-affinity α4β2 nAChRs are necessary for the effects of acute nicotine on contextual fear extinction. PMID:26688111

Treatment of exercise-induced asthma, respiratory and allergic disorders in sports and the relationship to doping: Part II of the report from the Joint Task Force of European Respiratory Society (ERS) and European Academy of Allergy and Clinical Immunology (EAACI) in cooperation with GA(2)LEN.

PubMed

Carlsen, K H; Anderson, S D; Bjermer, L; Bonini, S; Brusasco, V; Canonica, W; Cummiskey, J; Delgado, L; Del Giacco, S R; Drobnic, F; Haahtela, T; Larsson, K; Palange, P; Popov, T; van Cauwenberge, P

2008-05-01

The aims of part II is to review the current recommended treatment of exercise-induced asthma (EIA), respiratory and allergic disorders in sports, to review the evidence on possible improvement of performance in sports by asthma drugs and to make recommendations for their treatment. The literature cited with respect to the treatment of exercise induced asthma in athletes (and in asthma patients) is mainly based upon the systematic review given by Larsson et al. (Larsson K, Carlsen KH, Bonini S. Anti-asthmatic drugs: treatment of athletes and exercise-induced bronchoconstriction. In: Carlsen KH, Delgado L, Del Giacco S, editors. Diagnosis, prevention and treatment of exercise-related asthma, respiratory and allergic disorders in sports. Sheffield, UK: European Respiratory Journals Ltd, 2005:73-88) during the work of the Task Force. To assess the evidence of the literature regarding use of beta(2)-agonists related to athletic performance, the Task Force searched Medline for relevant papers up to November 2006 using the present search words: asthma, bronchial responsiveness, exercise-induced bronchoconstriction, athletes, sports, performance and beta(2)-agonists. Evidence level and grades of recommendation were assessed according to Sign criteria. Treatment recommendations for EIA and bronchial hyper-responsiveness in athletes are set forth with special reference to controller and reliever medications. Evidence for lack of improvement of exercise performance by inhaled beta(2)-agonists in healthy athletes serves as a basis for permitting their use. There is a lack of evidence of treatment effects of asthma drugs on EIA and bronchial hyper-responsiveness in athletes whereas extensive documentation exists in treatment of EIA in patients with asthma. The documentation on lack of improvement on performance by common asthma drugs as inhaled beta(2)-agonists with relationship to sports in healthy individuals is of high evidence, level (1+). Exercise induced asthma should be treated in athletes along same principles as in ordinary asthma patients with relevance to controller and reliever treatment after careful diagnosis. There is very high level of evidence for the lack of improvement in athletic performance by inhaled beta2-agonists.

Contrast Media Viscosity versus Osmolality in Kidney Injury: Lessons from Animal Studies

PubMed Central

Seeliger, Erdmann; Lenhard, Diana C.; Persson, Pontus B.

2014-01-01

Iodinated contrast media (CM) can induce acute kidney injury (AKI). CM share common iodine-related cytotoxic features but differ considerably with regard to osmolality and viscosity. Meta-analyses of clinical trials generally failed to reveal renal safety differences of modern CM with regard to these physicochemical properties. While most trials' reliance on serum creatinine as outcome measure contributes to this lack of clinical evidence, it largely relies on the nature of prospective clinical trials: effective prophylaxis by ample hydration must be employed. In everyday life, patients are often not well hydrated; here we lack clinical data. However, preclinical studies that directly measured glomerular filtration rate, intrarenal perfusion and oxygenation, and various markers of AKI have shown that the viscosity of CM is of vast importance. In the renal tubules, CM become enriched, as water is reabsorbed, but CM are not. In consequence, tubular fluid viscosity increases exponentially. This hinders glomerular filtration and tubular flow and, thereby, prolongs intrarenal retention of cytotoxic CM. Renal cells become injured, which triggers hypoperfusion and hypoxia, finally leading to AKI. Comparisons between modern CM reveal that moderately elevated osmolality has a renoprotective effect, in particular, in the dehydrated state, because it prevents excessive tubular fluid viscosity. PMID:24707482

Structural differences between yeast and mammalian microtubules revealed by cryo-EM

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

Howes, Stuart C.; Geyer, Elisabeth A.; LaFrance, Benjamin

Microtubules are polymers of αβ-tubulin heterodimers essential for all eukaryotes. Despite sequence conservation, there are significant structural differences between microtubules assembled in vitro from mammalian or budding yeast tubulin. Yeast MTs were not observed to undergo compaction at the interdimer interface as seen for mammalian microtubules upon GTP hydrolysis. Lack of compaction might reflect slower GTP hydrolysis or a different degree of allosteric coupling in the lattice. The microtubule plus end–tracking protein Bim1 binds yeast microtubules both between αβ-tubulin heterodimers, as seen for other organisms, and within tubulin dimers, but binds mammalian tubulin only at interdimer contacts. At the concentrationsmore » used in cryo-electron microscopy, Bim1 causes the compaction of yeast microtubules and induces their rapid disassembly. In conclusion, our studies demonstrate structural differences between yeast and mammalian microtubules that likely underlie their differing polymerization dynamics. These differences may reflect adaptations to the demands of different cell size or range of physiological growth temperatures.« less

A Low Frequency Electromagnetic Sensor for Indirect Measurement of Glucose Concentration: In Vitro Experiments in Different Conductive Solutions

PubMed Central

Tura, Andrea; Sbrignadello, Stefano; Cianciavicchia, Domenico; Pacini, Giovanni; Ravazzani, Paolo

2010-01-01

In recent years there has been considerable interest in the study of glucose-induced dielectric property variations of human tissues as a possible approach for non-invasive glycaemia monitoring. We have developed an electromagnetic sensor, and we tested in vitro its ability to estimate variations in glucose concentration of different solutions with similarities to blood (sodium chloride and Ringer-lactate solutions), differing though in the lack of any cellular components. The sensor was able to detect the effect of glucose variations over a wide range of concentrations (∼78–5,000 mg/dL), with a sensitivity of ∼0.22 mV/(mg/dL). Our proposed system may thus be useful in a new approach for non-invasive and non-contact glucose monitoring. PMID:22219665

HTLV-I and HTLV-II Tax: differences in induction of micronuclei in cells and transcriptional activation of viral LTRs.

PubMed

Semmes, O J; Majone, F; Cantemir, C; Turchetto, L; Hjelle, B; Jeang, K T

1996-03-01

Human T-cell leukemia virus (HTLV) types I and II are highly related viruses that differ in disease manifestations. HTLV-I has been linked unmistakably to adult T-cell leukemia-lymphoma. On the other hand, there is little evidence that prior infection with HTLV-II increases risk for lymphoproliferative disorders. Both viruses encode homologous transcriptional-activating proteins (respectively designated as Tax1 and Tax2) which have been suggested to be important mediators of viral pathogenesis. Previously, we reported that Tax1 is a potent inducer of micronuclei formation in cells. Here, we present evidence that Tax2 lacks micronuclei inductive ability. We contrast this phenotypic difference between Tax1 and Tax2 at the cellular level with their similarities at the molecular level in transcriptional activation.

Break-induced replication and recombinational telomere elongation in yeast.

PubMed

McEachern, Michael J; Haber, James E

2006-01-01

When a telomere becomes unprotected or if only one end of a chromosomal double-strand break succeeds in recombining with a template sequence, DNA can be repaired by a recombination-dependent DNA replication process termed break-induced replication (BIR). In budding yeasts, there are two BIR pathways, one dependent on the Rad51 recombinase protein and one Rad51 independent; these two repair processes lead to different types of survivors in cells lacking the telomerase enzyme that is required for normal telomere maintenance. Recombination at telomeres is triggered by either excessive telomere shortening or disruptions in the function of telomere-binding proteins. Telomere elongation by BIR appears to often occur through a "roll and spread" mechanism. In this process, a telomeric circle produced by recombination at a dysfunctional telomere acts as a template for a rolling circle BIR event to form an elongated telomere. Additional BIR events can then copy the elongated sequence to all other telomeres.

A look at the effect of sequence complexity on pressure destabilisation of DNA polymers.

PubMed

Rayan, Gamal; Macgregor, Robert B

2015-04-01

Our previous studies on the helix-coil transition of double-stranded DNA polymers have demonstrated that molar volume change (ΔV) accompanying the thermally-induced transition can be positive or negative depending on the experimental conditions, that the pressure-induced transition is more cooperative than the heat-induced transition [Rayan and Macgregor, J Phys Chem B2005, 109, 15558-15565], and that the pressure-induced transition does not occur in the absence of water [Rayan and Macgregor, Biophys Chem, 2009, 144, 62-66]. Additionally, we have shown that ΔV values obtained by pressure-dependent techniques differ from those obtained by ambient pressure techniques such as PPC [Rayan et al. J Phys Chem B2009, 113, 1738-1742] thus shedding light on the effects of pressure on DNA polymers. Herein, we examine the effect of sequence complexity, and hence cooperativity on pressure destabilisation of DNA polymers. Working with Clostridium perfringes DNA under conditions such that the estimated ΔV of the helix-coil transition corresponds to -1.78 mL/mol (base pair) at atmospheric pressure, we do not observe the pressure-induced helix-coil transition of this DNA polymer, whereas synthetic copolymers poly[d(A-T)] and poly[d(I-C)] undergo cooperative pressure-induced transitions at similar ΔV values. We hypothesise that the reason for the lack of pressure-induced helix-coil transition of C. perfringens DNA under these experimental conditions lies in its sequence complexity. Copyright © 2015 Elsevier B.V. All rights reserved.

Hepatocyte Toll-like receptor 4 regulates obesity-induced inflammation and insulin resistance

USDA-ARS?s Scientific Manuscript database

Chronic low-grade inflammation is a hallmark of obesity and thought to contribute to the development of obesity-related insulin resistance. Toll-like receptor 4 (Tlr4) is a key mediator of pro-inflammatory responses. Mice lacking Tlr4s are protected from diet-induced insulin resistance and inflammat...

Involvement of mitochondrial proteins in calcium signaling and cell death induced by staurosporine in Neurospora crassa.

PubMed

Gonçalves, A Pedro; Cordeiro, J Miguel; Monteiro, João; Lucchi, Chiara; Correia-de-Sá, Paulo; Videira, Arnaldo

2015-10-01

Staurosporine-induced cell death in Neurospora crassa includes a well defined sequence of alterations in cytosolic calcium levels, comprising extracellular Ca(2+) influx and mobilization of Ca(2+) from internal stores. Here, we show that cells undergoing respiratory stress due to the lack of certain components of the mitochondrial complex I (like the 51kDa and 14kDa subunits) or the Ca(2+)-binding alternative NADPH dehydrogenase NDE-1 are hypersensitive to staurosporine and incapable of setting up a proper intracellular Ca(2+) response. Cells expressing mutant forms of NUO51 that mimic human metabolic diseases also presented Ca(2+) signaling deficiencies. Accumulation of reactive oxygen species is increased in cells lacking NDE-1 and seems to be required for Ca(2+) oscillations in response to staurosporine. Measurement of the mitochondrial levels of Ca(2+) further supported the involvement of these organelles in staurosporine-induced Ca(2+) signaling. In summary, our data indicate that staurosporine-induced fungal cell death involves a sophisticated response linking Ca(2+) dynamics and bioenergetics. Copyright © 2015 Elsevier B.V. All rights reserved.

Infiltration of CD4+ lymphocytes into the brain contributes to neurodegeneration in a mouse model of Parkinson disease

PubMed Central

Brochard, Vanessa; Combadière, Béhazine; Prigent, Annick; Laouar, Yasmina; Perrin, Aline; Beray-Berthat, Virginie; Bonduelle, Olivia; Alvarez-Fischer, Daniel; Callebert, Jacques; Launay, Jean-Marie; Duyckaerts, Charles; Flavell, Richard A.; Hirsch, Etienne C.; Hunot, Stéphane

2008-01-01

Parkinson disease (PD) is a neurodegenerative disorder characterized by a loss of dopamine-containing neurons. Mounting evidence suggests that dopaminergic cell death is influenced by the innate immune system. However, the pathogenic role of the adaptive immune system in PD remains enigmatic. Here we showed that CD8+ and CD4+ T cells but not B cells had invaded the brain in both postmortem human PD specimens and in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD during the course of neuronal degeneration. We further demonstrated that MPTP-induced dopaminergic cell death was markedly attenuated in the absence of mature T lymphocytes in 2 different immunodeficient mouse strains (Rag1–/– and Tcrb–/– mice). Importantly, similar attenuation of MPTP-induced dopaminergic cell death was seen in mice lacking CD4 as well as in Rag1–/– mice reconstituted with FasL-deficient splenocytes. However, mice lacking CD8 and Rag1–/– mice reconstituted with IFN-γ–deficient splenocytes were not protected. These data indicate that T cell–mediated dopaminergic toxicity is almost exclusively arbitrated by CD4+ T cells and requires the expression of FasL but not IFNγ. Further, our data may provide a rationale for targeting the adaptive arm of the immune system as a therapeutic strategy in PD. PMID:19104149

Lack of HXK2 induces localization of active Ras in mitochondria and triggers apoptosis in the yeast Saccharomyces cerevisiae.

PubMed

Amigoni, Loredana; Martegani, Enzo; Colombo, Sonia

2013-01-01

We recently showed that activated Ras proteins are localized to the plasma membrane and in the nucleus in wild-type cells growing exponentially on glucose, while in the hxk2Δ strain they accumulated mainly in mitochondria. An aberrant accumulation of activated Ras in these organelles was previously reported and correlated to mitochondrial dysfunction, accumulation of ROS, and cell death. Here we show that addition of acetic acid to wild-type cells results in a rapid recruitment of Ras-GTP from the nucleus and the plasma membrane to the mitochondria, providing a further proof that Ras proteins might be involved in programmed cell death. Moreover, we show that Hxk2 protects against apoptosis in S. cerevisiae. In particular, cells lacking HXK2 and showing a constitutive accumulation of activated Ras at the mitochondria are more sensitive to acetic-acid-induced programmed cell death compared to the wild type strain. Indeed, deletion of HXK2 causes an increase of apoptotic cells with several morphological and biochemical changes that are typical of apoptosis, including DNA fragmentation, externalization of phosphatidylserine, and ROS production. Finally, our results suggest that apoptosis induced by lack of Hxk2 may not require the activation of Yca1, the metacaspase homologue identified in yeast.

Immune responses in space flight

NASA Technical Reports Server (NTRS)

Sonnenfeld, G.

1998-01-01

Space flight has been shown to have profound effects on immunological parameters of humans, monkeys and rodents. These studies have been carried out by a number of different laboratories. Among the parameters affected are leukocyte blastogenesis, natural killer cell activity, leukocyte subset distribution, cytokine production - including interferons and interleukins, and macrophage maturation and activity. These changes start to occur only after a few days space flight, and some changes continue throughout long-term space flight. Antibody responses have received only very limited study, and total antibody levels have been shown to be increased after long-term space flight. Several factors could be involved in inducing these changes. These factors could include microgravity, lack of load-bearing, stress, acceleration forces, and radiation. The mechanism(s) for space flight-induced changes in immune responses remain(s) to be established. Certainly, there can be direct effects of microgravity, or other factors, on cells that play a fundamental role in immune responses. However, it is now clear that there are interactions between the immune system and other physiological systems that could play a major role. For example, changes occurring in calcium use in the musculoskeletal system induced by microgravity or lack of use could have great impact on the immune system. Most of the changes in immune responses have been observed using samples taken immediately after return from space flight. However, there have been two recent studies that have used in-flight testing. Delayed-type hypersensitivity responses to common recall antigens of astronauts and cosmonauts have been shown to be decreased when tested during space flights. Additionally, natural killer cell and blastogenic activities are inhibited in samples taken from rats during space flight. Therefore, it is now clear that events occurring during space flight itself can affect immune responses. The biological significance of space flight-induced changes in immune parameters remains to be established; however, as duration of flights increases, the potential for difficulties due to impaired immune responses also increases.

2-(4-(Biphenyl-4-ylamino)-6-chloropyrimidin-2-ylthio)octanoic acid (HZ52) – a novel type of 5-lipoxygenase inhibitor with favourable molecular pharmacology and efficacy in vivo

PubMed Central

Greiner, C; Hörnig, C; Rossi, A; Pergola, C; Zettl, H; Schubert-Zsilavecz, M; Steinhilber, D; Sautebin, L; Werz, O

2011-01-01

BACKGROUND AND PURPOSE 5-Lipoxygenase (5-LO) is the key enzyme in the biosynthesis of pro-inflammatory leukotrienes (LTs) representing a potential target for pharmacological intervention with inflammation and allergic disorders. Although many LT synthesis inhibitors are effective in simple in vitro test systems, they frequently fail in vivo due to lack of efficacy. Here, we attempted to assess the pharmacological potential of the previously identified 5-LO inhibitor 2-(4-(biphenyl-4-ylamino)-6-chloropyrimidin-2-ylthio)octanoic acid (HZ52). EXPERIMENTAL APPROACH We evaluated the efficacy of HZ52 in vivo using carrageenan-induced pleurisy in rats and platelet-activating factor (PAF)-induced lethal shock in mice. We also characterized 5-LO inhibition by HZ52 at the cellular and molecular level in comparison with other types of 5-LO inhibitor, that is, BWA4C, ZM230487 and hyperforin. KEY RESULTS HZ52, 1.5 mg·kg−1 i.p., prevented carrageenan-induced pleurisy accompanied by reduced LTB4 levels and protected mice (10 mg·kg−1, i.p.) against PAF-induced shock. Detailed analysis in cell-based and cell-free assays revealed that inhibition of 5-LO by HZ52 (i) does not depend on radical scavenging properties and is reversible; (ii) is not impaired by an increased peroxide tone or by elevated substrate concentrations; and (iii) is little affected by the cell stimulus or by phospholipids, glycerides, membranes or Ca2+. CONCLUSIONS AND IMPLICATIONS HZ52 is a promising new type of 5-LO inhibitor with efficacy in vivo and with a favourable pharmacological profile. It possesses a unique 5-LO inhibitory mechanism different from classical 5-LO inhibitors and seemingly lacks the typical disadvantages of former classes of LT synthesis blockers. PMID:21506958

UV Induced Epigenetic Field Effect as a Target for Melanoma Therapy and Prevention

DTIC Science & Technology

2017-06-01

initiators or selected for during disease progression highlighting our lack in knowledge of the critical molecular targets in the initiation of UV...changes in the underlying molecular mechanisms of UV-induced melanoma. This would be the first evidence epigenetic alterations from UV-induced...i di id l i k d h l d fi li d i i15. SUBJECT TERMS Skin-cancer, melanoma, ultraviolet-radiation, epigenetics, methylation, genetics , melanomagenesis

Subtype specific internalization of P2Y1 and P2Y2 receptors induced by novel adenosine 5′-O-(1-boranotriphosphate) derivatives

PubMed Central

Tulapurkar, M E; Laubinger, W; Nahum, V; Fischer, B; Reiser, G

2004-01-01

P2Y-nucleotide receptors represent important targets for drug development. The lack of stable and receptor specific agonists, however, has prevented successful therapeutic applications. A novel series of P-boronated ATP derivatives (ATP-α-B) were synthesized by substitution of a nonbridging O at Pα with a BH3 group. This introduces a chiral center, thus resulting in diastereoisomers. In addition, at C2 of the adenine ring a further substitution was made (Cl- or methylthio-). The pairs of diastereoisomers were denoted here as A and B isomers. Here, we tested the receptor subtype specificity of these analogs on HEK 293 cells stably expressing rat P2Y1 and rat P2Y2 receptors, respectively, both attached to the fluorescent marker protein GFP (rP2Y1-GFP, rP2Y2-GFP). We investigated agonist-induced receptor endocytosis, [Ca2+]i rise and arachidonic acid (AA) release. Agonist-induced endocytosis of rP2Y1-GFP was more pronounced for the A isomers than the corresponding B counterparts for all ATP-α-B analogs. Both 2-MeS-substituted diastereoisomers induced a greater degree of agonist-induced receptor endocytosis as compared to the 2-Cl-substituted derivatives. Endocytosis results are in accordance with the potency to induce Ca2+ release by these compounds in HEK 293 cells stably transfected with rP2Y1. In case of rP2Y2-GFP, the borano-nucleotides were very weak agonists in comparison to UTP and ATP in terms of Ca2+ release, AA release and in inducing receptor endocytosis. The different ATP-α-B derivatives and also the diastereoisomers were equally ineffective. Thus, the new agonists may be considered as potent and highly specific agonist drug candidates for P2Y1 receptors. The difference in activity of the ATP analogs at P2Y receptors could be used as a tool to investigate structural differences between P2Y receptor subtypes. PMID:15197109

Cysteine analogues potentiate glucose-induced insulin release in vitro

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

Ammon, H.P.; Hehl, K.H.; Enz, G.

1986-12-01

In rat pancreatic islets, cysteine analogues, including glutathione, acetylcysteine, cysteamine, D-penicillamine, L-cysteine ethyl ester, and cysteine-potentiated glucose (11.1 mM) induced insulin secretion in a concentration-dependent manner. Their maximal effects were similar and occurred at approximately 0.05, 0.05, 0.1, 0.5, 1.0, 1.0 mM, respectively. At substimulatory glucose levels (2.8 mM), insulin release was not affected by these compounds. In contrast, thiol compounds, structurally different from cysteine and its analogues, such as mesna, tiopronin, meso-2,3-dimercaptosuccinic acid (DMSA), dimercaprol (BAL), beta-thio-D-glucose, as well as those cysteine analogues that lack a free-thiol group, including L-cystine, cystamine, D-penicillamine disulfide, S-carbocysteine, and S-carbamoyl-L-cysteine, did not enhancemore » insulin release at stimulatory glucose levels (11.1 mM); cystine (5 mM) was inhibitory. These in vitro data indicate that among the thiols tested here, only cysteine and its analogues potentiate glucose-induced insulin secretion, whereas thiols that are structurally not related to cysteine do not. This suggests that a cysteine moiety in the molecule is necessary for the insulinotropic effect. For their synergistic action to glucose, the availability of a sulfhydryl group is also a prerequisite. The maximal synergistic action is similar for all cysteine analogues tested, whereas the potency of action is different, suggesting similarity in the mechanism of action but differences in the affinity to the secretory system.« less

Temperature-dependent conformational variation of chromophoric dissolved organic matter and its consequent interaction with phenanthrene.

PubMed

Chen, Wei; Liu, Xiao-Yang; Yu, Han-Qing

2017-03-01

Temperature variation caused by climate change, seasonal variation and geographic locations affects the physicochemical compositions of chromophoric dissolved organic matter (CDOM), resulting in difference in the fates of CDOM-related environmental pollutants. Exploration into the thermal induced structural transition of CDOM can help to better understand their environmental impacts, but information on this aspect is still lacking. Through integrating fluorescence excitation-emission matrix coupled parallel factor analysis with synchronous fluorescence two-dimensional correlation spectroscopy, this study provides an in-depth insight into the temperature-dependent conformational transitions of CDOM and their impact on its hydrophobic interaction with persistent organic pollutants (with phenanthrene as an example) in water. The fluorescence components in CDOM change linearly to water temperature with different extents and different temperature regions. The thermal induced transition priority in CDOM is protein-like component → fulvic-like component → humic-like component. Furthermore, the impact of thermal-induced conformational transition of CDOM on its hydrophobic interaction with phenanthrene is observed and explored. The fluorescence-based analytic results reveal that the conjugation degree of the aromatic groups in the fulvic- and humic-like substances, and the unfolding of the secondary structure in the protein-like substances with aromatic structure, contribute to the conformation variation. This integrated approach jointly enhances the characterization of temperature-dependent conformational variation of CDOM, and provides a promising way to elucidate the environmental behaviours of CDOM. Copyright © 2017 Elsevier Ltd. All rights reserved.

Concise review: reprogramming strategies for cardiovascular regenerative medicine: from induced pluripotent stem cells to direct reprogramming.

PubMed

Budniatzky, Inbar; Gepstein, Lior

2014-04-01

Myocardial cell-replacement therapies are emerging as novel therapeutic paradigms for myocardial repair but are hampered by the lack of sources of autologous human cardiomyocytes. The recent advances in stem cell biology and in transcription factor-based reprogramming strategies may provide exciting solutions to this problem. In the current review, we describe the different reprogramming strategies that can give rise to cardiomyocytes for regenerative medicine purposes. Initially, we describe induced pluripotent stem cell technology, a method by which adult somatic cells can be reprogrammed to yield pluripotent stem cells that could later be coaxed ex vivo to differentiate into cardiomyocytes. The generated induced pluripotent stem cell-derived cardiomyocytes could then be used for myocardial cell transplantation and tissue engineering strategies. We also describe the more recent direct reprogramming approaches that aim to directly convert the phenotype of one mature cell type (fibroblast) to another (cardiomyocyte) without going through a pluripotent intermediate cell type. The advantages and shortcomings of each strategy for cardiac regeneration are discussed, along with the hurdles that need to be overcome on the road to clinical translation.

Statin Lactonization by Uridine 5'-Diphospho-glucuronosyltransferases (UGTs).

PubMed

Schirris, Tom J J; Ritschel, Tina; Bilos, Albert; Smeitink, Jan A M; Russel, Frans G M

2015-11-02

Statins are cholesterol-lowering drugs that have proven to be effective in lowering the risk of major cardiovascular events. Although well tolerated, statin-induced myopathies are the most common side effects. Compared to their pharmacologically active acid form, statin lactones are more potent inducers of toxicity. They can be formed by glucuronidation mediated by uridine 5'-diphospho-glucuronosyltransferases (UGTs), but a systematic characterization of subtype specificity and kinetics of lactonization is lacking. Here, we demonstrate for six clinically relevant statins that only UGT1A1, 1A3, and 2B7 contribute significantly to their lactonization. UGT1A3 appeared to have the highest lactonization capacity with marked differences in statin conversion rates: pitavastatin ≫ atorvastatin > cerivastatin > lovastatin > rosuvastatin (simvastatin not converted). Using in silico modeling we could identify a probable statin interaction region in the UGT binding pocket. Polymorphisms in these regions of UGT1A1, 1A3, and 2B7 may be a contributing factor in statin-induced myopathies, which could be used in personalization of statin therapy with improved safety.

Transcranial magnetic stimulation: no effect on mood with single pulse during learned helplessness.

PubMed

Habel, U; Wild, B; Topka, H; Kircher, T; Salloum, J B; Schneider, F

2001-04-01

1. Transcranial Magnetic Stimulation (TMS) is suggested to be an effective tool in the treatment of depression. However, the methodology most suitable for clinical application remains unclear. 2. The effect of TMS was tested in a double-blind and placebo-controlled setting on 18 healthy subjects. At the same time an established learned helplessness paradigm was applied to induce dysphoria, which consisted of unsolvable anagrams. 3. Sixty 0.5 Hz stimuli were administered at an intensity of 130% of the subject's motor threshold after the subjects were exposed to the learned helplessness situation. Using a vertically positioned coil, the stimuli were applied to the right or to the left frontal cortex, or on the occipital cortex as a placebo condition. 4. Although dysphoria was successfully induced by unsolvable anagrams, TMS on either of the two frontal locations did not influence mood. This lack of effect may be due to the stimulation characteristics employed here (low TMS intensity, and low frequency). On the other hand, the findings may reflect the neurobiological difference between experimentally induced sad mood and clinical depression.

Adenovirus vector-induced immune responses in nonhuman primates: responses to prime boost regimens1

PubMed Central

Tatsis, Nia; Lasaro, Marcio O.; Lin, Shih-Wen; Xiang, Zhi Q.; Zhou, Dongming; DiMenna, Lauren; Li, Hua; Bian, Ang; Abdulla, Sarah; Li, Yan; Giles-Davis, Wynetta; Engram, Jessica; Ratcliffe, Sarah J.; Silvestri, Guido; Ertl, Hildegund C.; Betts, Michael R.

2009-01-01

In the phase IIb STEP trial an HIV-1 vaccine based on adenovirus (Ad) vectors of the human serotype 5 (AdHu5) not only failed to induce protection but also increased susceptibility to HIV-1 infection in individuals with pre-existing neutralizing antibodies against AdHu5. The mechanisms underlying the increased HIV-1 acquisition rates have not yet been elucidated. Furthermore, it remains unclear if the lack of the vaccine's efficacy reflects a failure of the concept of T cell-mediated protection against HIV-1 or a product failure of the vaccine. Here we compared two vaccine regimens based on sequential use of AdHu5 vectors or two different chimpanzee derived Ad (AdC) vectors in rhesus macaques that were AdHu5 seropositive or seronegative at the onset of vaccination. Our results show that heterologous booster immunizations with the AdC vectors induced higher T and B cell responses than repeated immunizations with the AdHu5 vector especially in AdHu5-pre-exposed macaques. PMID:19414814

Glucocorticoid-induced tethered transrepression requires SUMOylation of GR and formation of a SUMO-SMRT/NCoR1-HDAC3 repressing complex

PubMed Central

Hua, Guoqiang; Ganti, Krishna Priya; Chambon, Pierre

2016-01-01

Upon binding of a glucocorticoid (GC), the GC receptor (GR) can exert one of three transcriptional regulatory functions. We recently reported that SUMOylation of the GR at position K293 in humans (K310 in mice) within the N-terminal domain is indispensable for GC-induced evolutionary conserved inverted repeated negative GC response element (IR nGRE)-mediated direct transrepression. We now demonstrate that the integrity of this GR SUMOylation site is mandatory for the formation of a GR-small ubiquitin-related modifiers (SUMOs)-SMRT/NCoR1-HDAC3 repressing complex, which is indispensable for NF-κB/AP1-mediated GC-induced tethered indirect transrepression in vitro. Using GR K310R mutant mice or mice containing the N-terminal truncated GR isoform GRα-D3 lacking the K310 SUMOylation site, revealed a more severe skin inflammation than in WT mice. Importantly, cotreatment with dexamethasone (Dex) could not efficiently suppress a 12-O-tetradecanoylphorbol-13-acetate (TPA)–induced skin inflammation in these mutant mice, whereas it was clearly decreased in WT mice. In addition, in mice selectively ablated in skin keratinocytes for either nuclear receptor corepressor 1 (NCoR1)/silencing mediator for retinoid or thyroid-hormone receptors (SMRT) corepressors or histone deacetylase 3 (HDAC3), Dex-induced tethered transrepression and the formation of a repressing complex on DNA-bound NF-κB/AP1 were impaired. We previously suggested that GR ligands that would lack both (+)GRE-mediated transactivation and IR nGRE-mediated direct transrepression activities of GCs may preferentially exert the therapeutically beneficial GC antiinflammatory properties. Interestingly, we now identified a nonsteroidal antiinflammatory selective GR agonist (SEGRA) that selectively lacks both Dex-induced (+)GRE-mediated transactivation and IR nGRE-mediated direct transrepression functions, while still exerting a tethered indirect transrepression activity and could therefore be clinically lesser debilitating on long-term GC therapy. PMID:26712006

PGC-1α and fasting-induced PDH regulation in mouse skeletal muscle.

PubMed

Gudiksen, Anders; Pilegaard, Henriette

2017-04-01

The purpose of the present study was to examine whether lack of skeletal muscle peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1 α ) affects the switch in substrate utilization from a fed to fasted state and the fasting-induced pyruvate dehydrogenase (PDH) regulation in skeletal muscle. Skeletal muscle-specific PGC-1 α knockout (MKO) mice and floxed littermate controls were fed or fasted for 24 h. Fasting reduced PDHa activity, increased phosphorylation of all four known sites on PDH-E1 α and increased pyruvate dehydrogenase kinase (PDK4) and sirtuin 3 (SIRT3) protein levels, but did not alter total acetylation of PDH-E1 α Lack of muscle PGC-1 α did not affect the switch from glucose to fat oxidation in the transition from the fed to fasted state, but was associated with lower and higher respiratory exchange ratio (RER) in the fed and fasted state, respectively. PGC-1 α MKO mice had lower skeletal muscle PDH-E1 α , PDK1, 2, 4, and pyruvate dehydrogenase phosphatase (PDP1) protein content than controls, but this did not prevent the fasting-induced increase in PDH-E1 α phosphorylation in PGC-1 α MKO mice. However, lack of skeletal muscle PGC-1 α reduced SIRT3 protein content, increased total lysine PDH-E1 α acetylation in the fed state, and prevented a fasting-induced increase in SIRT3 protein. In conclusion, skeletal muscle PGC-1 α is required for fasting-induced upregulation of skeletal muscle SIRT3 and maintaining high fat oxidation in the fasted state, but is dispensable for preserving the capability to switch substrate during the transition from the fed to the fasted state and for fasting-induced PDH regulation in skeletal muscle. © 2017 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.

Lack of Evidence That Neural Empathic Responses Are Blunted in Excessive Users of Violent Video Games: An fMRI Study.

PubMed

Szycik, Gregor R; Mohammadi, Bahram; Münte, Thomas F; Te Wildt, Bert T

2017-01-01

The use of violent video games has been often linked to increase of aggressive behavior. According to the General Aggression Model, one of the central mechanisms for this aggressiveness inducing impact is an emotional desensitization process resulting from long lasting repeated violent game playing. This desensitization should evidence itself in a lack of empathy. Recent research has focused primarily on acute, short term impact of violent media use but only little is known about long term effects. In this study 15 excessive users of violent games and control subjects matched for age and education viewed pictures depicting emotional and neutral situations with and without social interaction while fMRI activations were obtained. While the typical pattern of activations for empathy and theory of mind networks was seen, both groups showed no differences in brain responses. We interpret our results as evidence against the desensitization hypothesis and suggest that the impact of violent media on emotional processing may be rather acute and short-lived.

Long-term high-fat feeding induces greater fat storage in mice lacking UCP3.

PubMed

Costford, Sheila R; Chaudhry, Shehla N; Crawford, Sean A; Salkhordeh, Mahmoud; Harper, Mary-Ellen

2008-11-01

Uncoupling protein-3 (UCP3) is a mitochondrial inner-membrane protein highly expressed in skeletal muscle. While UCP3's function is still unknown, it has been hypothesized to act as a fatty acid (FA) anion exporter, protecting mitochondria against lipid peroxidation and/or facilitating FA oxidation. The aim of this study was to determine the effects of long-term feeding of a 45% fat diet on whole body indicators of muscle metabolism in congenic C57BL/6 mice that were either lacking UCP3 (Ucp3(-/-)) or had a transgenically induced approximately twofold increase in UCP3 levels (UCP3tg). Mice were fed the high-fat (HF) diet for a period of either 4 or 8 mo immediately following weaning. After long-term HF feeding, UCP3tg mice weighed an average of 15% less than wild-type mice (P < 0.05) and were 20% less metabolically efficient than both wild-type and Ucp3(-/-) mice (P < 0.01). Additionally, wild-type mice had 21% lower, whereas UCP3tg mice had 36% lower, levels of adiposity compared with Ucp3(-/-) mice (P < 0.05 and P < 0.001, respectively), indicating a protective effect of UCP3 against fat gain. No differences in whole body oxygen consumption were detected following long-term HF feeding. Glucose and insulin tolerance tests revealed that both the UCP3tg and Ucp3(-/-) mice were more glucose tolerant and insulin sensitive compared with wild-type mice after short-term HF feeding, but this protection was not maintained in the long term. Findings indicate that UCP3 is involved in protection from fat gain induced by long-term HF feeding, but not in protection from insulin resistance.

Genetically defined fear-induced aggression: Focus on BDNF and its receptors.

PubMed

Ilchibaeva, Tatiana V; Tsybko, Anton S; Kozhemyakina, Rimma V; Kondaurova, Elena M; Popova, Nina K; Naumenko, Vladimir S

2018-05-02

Brain-derived neurotrophic factor (BDNF), its precursor proBDNF, BDNF pro-peptide, BDNF mRNA levels, as well as TrkB and p75 NTR receptors mRNA and protein levels, were studied in the brain of rats, selectively bred for more than 85 generations for either the high level or the lack of fear-induced aggressive behavior. Furthermore, we have found that rats of aggressive strain demonstrated both high level of aggression toward humans and increased amplitude of acoustic startle response compared to rats selectively bred for the lack of fear-induced aggression. Significant increase in the BDNF mRNA, mature BDNF and proBDNF protein levels in the raphe nuclei (RN), hippocampus (Hc), nucleus accumbens (NAcc), amygdala, striatum and hypothalamus (Ht) of aggressive rats was revealed. The BDNF/proBDNF ratio was significantly reduced in the Hc and NAcc of highly aggressive rats suggesting prevalence of the proBDNF in these structures. In the Hc and frontal cortex (FC) of aggressive rats, the level of the full-length TrkB (TrkB-FL) receptor form was decreased, whereas the truncated TrkB (TrkB-T) protein level was increased in the RN, FC, substantia nigra and Ht. The TrkB-FL/TrkB-T ratio was significantly decreased in highly aggressive rats suggesting TrkB-T is predominant in highly aggressive rats. The p75 NTR expression was slightly changed in majority of studied brain structures of aggressive rats. The data indicate the BDNF system in the brain of aggressive and nonaggressive animals is extremely different at all levels, from transcription to reception, suggesting significant role of BDNF system in the development of highly aggressive phenotype. Copyright © 2018 Elsevier B.V. All rights reserved.

Regulation of inflammation-associated olfactory neuronal death and regeneration by the type II tumor necrosis factor receptor.

PubMed

Pozharskaya, Tatyana; Liang, Jonathan; Lane, Andrew P

2013-09-01

Olfactory loss is a debilitating symptom of chronic rhinosinusitis. To study the impact of inflammation on the olfactory system, the inducible olfactory inflammation (IOI) transgenic mouse was created in which inflammation can be turned on and off within the olfactory epithelium. In this study, the type II tumor necrosis factor (TNF) receptor (TNFR2) was knocked out, and the effect on the olfactory loss phenotype was assessed. IOI mice were bred to TNFR2 knockout mice to yield progeny IOI mice lacking the TNFR2 receptor (TNFR2(-/-) ). TNF-α expression was induced within the olfactory epithelium for 6 weeks to generate chronic inflammation. Olfactory function was assayed by electro-olfactogram (EOG), and olfactory tissue was processed for histology and immunohistochemical staining. Compared to IOI mice with wild-type TNFR2, IOI mice lacking the TNFR2 demonstrated similar levels of inflammatory infiltration and enlargement of the subepithelial layer. However, IOI-TNFR2(-/-) mice differed markedly in that the neuronal layer was largely preserved and active progenitor cell proliferation was present. Odorant responses were maintained in the IOI-TNFR2(-/-) mice, in contrast to IOI mice. TNFR2 is the minor receptor for TNF-α, but appears to play an important role in mediating TNF-induced disruption of the olfactory system. This finding suggests that neuronal death and inhibition of proliferation in CRS may be mediated by TNFR2 on olfactory neurons and progenitor cells. Further studies are needed to elucidate the subcellular pathways involved and develop novel therapies for treating olfactory loss in the setting of CRS. © 2013 ARS-AAOA, LLC.

Doxofylline does not increase formoterol-induced cAMP nor MKP-1 expression in ASM cells resulting in lack of anti-inflammatory effect.

PubMed

Patel, Brijeshkumar S; Kugel, Michael J; Baehring, Gina; Ammit, Alaina J

2017-08-01

The xanthine doxofylline has been examined in clinical trials and shown to have efficacy and greater tolerability than theophylline in asthma and chronic obstructive pulmonary disease. The 'novofylline' doxofylline has demonstrated bronchodilatory and anti-inflammatory actions in in vivo and ex vivo experimental models of respiratory disease. However, there are limited studies in vitro. We address this herein and examine whether doxofylline has anti-inflammatory impact on primary cultures of airway smooth muscle (ASM) cells. We conduct a series of investigations comparing and contrasting doxofylline with the archetypal xanthine, theophylline, and the specific phosphodiesterase (PDE) 4 inhibitor, cilomilast. We confirm that the xanthine drugs do not have action as PDE inhibitors in ASM cells. Unlike cilomilast, doxofylline (and theophylline) do not increase cAMP production in ASM cells induced by long-acting β 2 -agonist formoterol. Similar to theophylline, and consistent with the lack of cAMP potentiation, doxofylline does not augment formoterol-induced upregulation of the anti-inflammatory protein mitogen-activated protein kinase phosphatase 1 (MKP-1). However, when we examine the effect of doxofylline on secretion of the interleukin 8 from ASM cells stimulated by tumour necrosis factor (an in vitro surrogate measure of inflammation), there was no repression of inflammation. This is in contrast to the anti-inflammatory impact exerted by theophylline and cilomilast in confirmatory experiments. In summary, our study is the first to examine the effect of doxofylline on ASM cells in vitro and highlights some distinct differences between two key members of xanthine drug family, doxofylline and theophylline. Copyright © 2017 Elsevier Ltd. All rights reserved.

2,4-Dichlorophenoxyacetic acid (2,4-D)- and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)-degrading gene cluster in the soybean root-nodulating bacterium Bradyrhizobium elkanii USDA94.

PubMed

Hayashi, Shohei; Sano, Tomoki; Suyama, Kousuke; Itoh, Kazuhito

2016-01-01

Herbicides 2,4-dichlorophenoxyacetic acid (2,4-D)- and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T)-degrading Bradyrhizobium strains possess tfdAα and/or cadABC as degrading genes. It has been reported that root-nodulating bacteria belonging to Bradyrhizobium elkanii also have tfdAα and cadA like genes but lack the ability to degrade these herbicides and that the cadA genes in 2,4-D-degrading and non-degrading Bradyrhizobium are phylogenetically different. In this study, we identified cadRABCK in the genome of a type strain of soybean root-nodulating B. elkanii USDA94 and demonstrated that the strain could degrade the herbicides when cadABCK was forcibly expressed. cadABCK-cloned Escherichia coli also showed the degrading ability. Because co-spiked phenoxyacetic acid (PAA) could induce the degradation of 2,4-D in B. elkanii USDA94, the lack of degrading ability in this strain was supposed to be due to the low inducing potential of the herbicides for the degrading gene cluster. On the other hand, tfdAα from B. elkanii USDA94 showed little potential to degrade the herbicides, but it did for 4-chlorophenoxyacetic acid and PAA. The 2,4-D-degrading ability of the cad cluster and the inducing ability of PAA were confirmed by preparing cadA deletion mutant. This is the first study to demonstrate that the cad cluster in the typical root-nodulating bacterium indeed have the potential to degrade the herbicides, suggesting that degrading genes for anthropogenic compounds could be found in ordinary non-degrading bacteria. Copyright © 2016 Elsevier GmbH. All rights reserved.

Simvastatin-lnduced nocturnal leg pain disappears with pravastatin substitution.

PubMed

Stojaković, Natasa; Igić, Rajko

2013-01-01

Statins have similar side effects that do not always occur at the same rate among the various statins. We present a case of simvastatin-induced muscle toxicity that disappeared when pravastatin was substituted for the original drug. A 74-year-old male, a nonsmoker, complained of severe nocturnal leg cramps. The patient also complained that similar painful cramping occurred when he walked rapidly or jogged. Because some components of his lipid panel exceeded the'desirable' range, and as he had a history of myocardial infarction, his family physician prescribed simvastatin (40 mg/day). The patient had taken this medication for the past eight years. The painful nocturnal episodes started two years ago and affected either one or the other leg. Four months ago we discontinued his simvastatin and prescribed pravastatin (80 mg/day). At a follow-up visit six weeks later, the patient reported that his leg pains at night and the pain experienced after brisk walking had disappeared. Four months after the substitution of pravastatin for simvastatin, the patient reported that his complete lack of symptoms had continued. These painful muscle cramps were probably caused by an inadequate vascular supply to the calf and foot muscles. Perhaps a combination of advanced age and atherosclerotic changes created a predisposition for the simvastatin-induced leg cramps. Pravastatin differs from simvastatin in several ways.l It is not metabolized by cytochrome P450 (CYP) 3A4 oxidases, and thus is not influenced by CYP 3A4 inhibitors like simvastatin. Also, simvastatin is associated with single-nucleotide polymorphisms located within the SLCO1B1 gene on the chromosome 12 and established myopathy, while pravastatin lacks this association. These differences may contribute to increased tolerance to pravastatin in this particular case.

Chlorophyll a/b-binding proteins, pigment conversions, and early light-induced proteins in a chlorophyll b-less barley mutant.

PubMed Central

Król, M; Spangfort, M D; Huner, N P; Oquist, G; Gustafsson, P; Jansson, S

1995-01-01

Monospecific polyclonal antibodies have been raised against synthetic peptides derived from the primary sequences from different plant light-harvesting Chl a/b-binding (LHC) proteins. Together with other monospecific antibodies, these were used to quantify the levels of the 10 different LHC proteins in wild-type and chlorina f2 barley (Hordeum vulgare L.), grown under normal and intermittent light (ImL). Chlorina f2, grown under normal light, lacked Lhcb1 (type I LHC II) and Lhcb6 (CP24) and had reduced amounts of Lhcb2, Lhcb3 (types II and III LHC II), and Lhcb4 (CP 29). Chlorina f2 grown under ImL lacked all LHC proteins, whereas wild-type ImL plants contained Lhcb5 (CP 26) and a small amount of Lhcb2. The chlorina f2 ImL thylakoids were organized in large parallel arrays, but wild-type ImL thylakoids had appressed regions, indicating a possible role for Lhcb5 in grana stacking. Chlorina f2 grown under ImL contained considerable amounts of violaxanthin (2-3/reaction center), representing a pool of phototransformable xanthophyll cycle pigments not associated with LHC proteins. Chlorina f2 and the plants grown under ImL also contained early light-induced proteins (ELIPs) as monitored by western blotting. The levels of both ELIPs and xanthophyll cycle pigments increased during a 1 h of high light treatment, without accumulation of LHC proteins. These data are consistent with the hypothesis that ELIPs are pigment-binding proteins, and we suggest that ELIPs bind photoconvertible xanthophylls and replace "normal" LHC proteins under conditions of light stress. PMID:7748263

Ethanol-related behaviors in mice lacking the sigma-1 receptor.

PubMed

Valenza, Marta; DiLeo, Alyssa; Steardo, Luca; Cottone, Pietro; Sabino, Valentina

2016-01-15

The Sigma-1 receptor (Sig-1R) is a chaperone protein that has been implicated in drug abuse and addiction. Multiple studies have characterized the role the Sig-1R plays in psychostimulant addiction; however, fewer studies have specifically investigated its role in alcohol addiction. We have previously shown that antagonism of the Sig-1R reduces excessive drinking and motivation to drink, whereas agonism induces binge-like drinking in rodents. The objectives of these studies were to investigate the impact of Sig-1R gene deletion in C57Bl/6J mice on ethanol drinking and other ethanol-related behaviors. We used an extensive panel of behavioral tests to examine ethanol actions in male, adult mice lacking Oprs1, the gene encoding the Sig-1R. To compare ethanol drinking behavior, Sig-1 knockout (KO) and wild type (WT) mice were subject to a two-bottle choice, continuous access paradigm with different concentrations of ethanol (3-20% v/v) vs. water. Consumption of sweet and bitter solutions was also assessed in Sig-1R KO and WT mice. Finally, motor stimulant sensitivity, taste aversion and ataxic effects of ethanol were assessed. Sig-1R KO mice displayed higher ethanol intake compared to WT mice; the two genotypes did not differ in their sweet or bitter taste perception. Sig-1R KO mice showed lower sensitivity to ethanol stimulant effects, but greater sensitivity to its taste aversive effects. Ethanol-induced sedation was instead unaltered in the mutants. Our results prove that the deletion of the Sig-1R increases ethanol consumption, likely by decreasing its rewarding effects, and therefore indicating that the Sig-1R is involved in modulation of the reinforcing effects of alcohol. Copyright © 2015 Elsevier B.V. All rights reserved.

Ethanol-related behaviors in mice lacking the sigma-1 receptor

PubMed Central

Valenza, Marta; DiLeo, Alyssa; Steardo, Luca; Cottone, Pietro; Sabino, Valentina

2015-01-01

Rationale The Sigma-1 receptor (Sig-1R) is a chaperone protein that has been implicated in drug abuse and addiction. Multiple studies have characterized the role the Sig-1R plays in psychostimulants addiction, but fewer studies have specifically investigated its role in alcohol addiction. We have previously shown that antagonism of the Sig-1R reduces excessive drinking and motivation to drink, whereas agonism induces binge-like drinking in rodents. Objectives The objectives of these studies were to investigate the impact of Sig-1R gene deletion in C57Bl/6J mice on ethanol drinking and other ethanol-related behaviors. Methods We used an extensive panel of behavioral tests to examine ethanol actions in male, adult mice lacking Oprs1, the gene encoding the Sig-1R. To compare ethanol drinking behavior, Sig-1 knockout (KO) and wild type (WT) mice were subject to a two-bottle choice, continuous access paradigm with different concentrations of ethanol (3%–20% v/v) vs. water. Consumption of sweet and bitter solutions was also assessed in Sig-1R KO and WT mice. Finally, motor stimulant sensitivity, taste aversion and ataxic effects of ethanol were assessed. Results Sig-1R KO mice displayed higher ethanol intake compared to WT mice; the two genotypes did not differ in their sweet or bitter taste perception. Sig-1R KO mice showed lower sensitivity to ethanol stimulant effects, but greater sensitivity to its taste aversive effects. Ethanol-induced sedation was unaltered in the mutants. Conclusions Our results suggest that the deletion of the Sig-1R increases ethanol consumption, likely by decreasing its rewarding effects, and therefore indicating that the Sig-1R is involved in modulation of the reinforcing effects of alcohol. PMID:26462569

Heterologous expression of anti-apoptotic human 14-3-3β/α enhances iron-mediated programmed cell death in yeast

PubMed Central

Eid, Rawan; Zhou, David R.; Arab, Nagla T. T.; Boucher, Eric; Young, Paul G.; Mandato, Craig A.

2017-01-01

The induction of Programmed Cell Death (PCD) requires the activation of complex responses involving the interplay of a variety of different cellular proteins, pathways, and processes. Uncovering the mechanisms regulating PCD requires an understanding of the different processes that both positively and negatively regulate cell death. Here we have examined the response of normal as well as PCD resistant yeast cells to different PCD inducing stresses. As expected cells expressing the pro-survival human 14-3-3β/α sequence show increased resistance to numerous stresses including copper and rapamycin. In contrast, other stresses including iron were more lethal in PCD resistant 14-3-3β/α expressing cells. The increased sensitivity to PCD was not iron and 14-3-3β/α specific since it was also observed with other stresses (hydroxyurea and zinc) and other pro-survival sequences (human TC-1 and H-ferritin). Although microscopical examination revealed little differences in morphology with iron or copper stresses, cells undergoing PCD in response to high levels of prolonged copper treatment were reduced in size. This supports the interaction some forms of PCD have with the mechanisms regulating cell growth. Analysis of iron-mediated effects in yeast mutant strains lacking key regulators suggests that a functional vacuole is required to mediate the synergistic effects of iron and 14-3-3β/α on yeast PCD. Finally, mild sub-lethal levels of copper were found to attenuate the observed inhibitory effects of iron. Taken together, we propose a model in which a subset of stresses like iron induces a complex process that requires the cross-talk of two different PCD inducing pathways. PMID:28854230

Carboxyl-terminal Domain of Transient Receptor Potential Vanilloid 1 Contains Distinct Segments Differentially Involved in Capsaicin- and Heat-induced Desensitization*

PubMed Central

Joseph, John; Wang, Sen; Lee, Jongseok; Ro, Jin Y.; Chung, Man-Kyo

2013-01-01

Multiple Ca2+-dependent processes are involved in capsaicin-induced desensitization of transient receptor potential vanilloid 1 (TRPV1), but desensitization of TRPV1 by heat occurs even in the absence of extracellular Ca2+, although the mechanisms are unknown. In this study, we tested the hypothesis that capsaicin and heat desensitize TRPV1 through distinct mechanisms involving distinct structural segments of TRPV1. In HEK293 cells that heterologously express TRPV1, we found that heat-induced desensitization was not affected by the inclusion of intracellular ATP or alanine mutation of Lys155, both of which attenuate capsaicin-induced desensitization, suggesting that heat-induced desensitization occurs through mechanisms distinct from capsaicin-induced desensitization. To determine protein domains involved in heat-induced desensitization, we generated chimeric proteins between TRPV1 and TRPV3, a heat-gated channel lacking heat-induced desensitization. We found that TRPV1 with the carboxyl-terminal domain (CTD) of TRPV3 retained heat activation but was impaired in heat-induced desensitization. Further experiments using chimeric or deletion mutants within TRPV1 CTD indicated that the distal half of CTD regulates the activation and desensitization of TRPV1 in modality-specific manners. Within the distal CTD, we identified two segments that distinctly regulated capsaicin- and heat-induced desensitization. The results suggest that the activation and desensitization of TRPV1 by capsaicin and heat can be modulated differentially and disproportionally through different regions of TRPV1 CTD. Identifying the domains involved in thermal regulation of TRPV1 may facilitate the development of novel anti-hyperalgesic approaches aimed at attenuating activation and enhancing desensitization of TRPV1 by thermal stimuli. PMID:24174527

Galanin-Expressing GABA Neurons in the Lateral Hypothalamus Modulate Food Reward and Noncompulsive Locomotion.

PubMed

Qualls-Creekmore, Emily; Yu, Sangho; Francois, Marie; Hoang, John; Huesing, Clara; Bruce-Keller, Annadora; Burk, David; Berthoud, Hans-Rudolf; Morrison, Christopher D; Münzberg, Heike

2017-06-21

The lateral hypothalamus (LHA) integrates reward and appetitive behavior and is composed of many overlapping neuronal populations. Recent studies associated LHA GABAergic neurons (LHA GABA ), which densely innervate the ventral tegmental area (VTA), with modulation of food reward and consumption; yet, LHA GABA projections to the VTA exclusively modulated food consumption, not reward. We identified a subpopulation of LHA GABA neurons that coexpress the neuropeptide galanin (LHA Gal ). These LHA Gal neurons also modulate food reward, but lack direct VTA innervation. We hypothesized that LHA Gal neurons may represent a subpopulation of LHA GABA neurons that mediates food reward independent of direct VTA innervation. We used chemogenetic activation of LHA Gal or LHA GABA neurons in mice to compare their role in feeding behavior. We further analyzed locomotor behavior to understand how differential VTA connectivity and transmitter release in these LHA neurons influences this behavior. LHA Gal or LHA GABA neuronal activation both increased operant food-seeking behavior, but only activation of LHA GABA neurons increased overall chow consumption. Additionally, LHA Gal or LHA GABA neuronal activation similarly induced locomotor activity, but with striking differences in modality. Activation of LHA GABA neurons induced compulsive-like locomotor behavior; while LHA Gal neurons induced locomotor activity without compulsivity. Thus, LHA Gal neurons define a subpopulation of LHA GABA neurons without direct VTA innervation that mediate noncompulsive food-seeking behavior. We speculate that the striking difference in compulsive-like locomotor behavior is also based on differential VTA innervation. The downstream neural network responsible for this behavior and a potential role for galanin as neuromodulator remains to be identified. SIGNIFICANCE STATEMENT The lateral hypothalamus (LHA) regulates motivated feeding behavior via GABAergic LHA neurons. The molecular identity of LHA GABA neurons is heterogeneous and largely undefined. Here we introduce LHA Gal neurons as a subset of LHA GABA neurons that lack direct innervation of the ventral tegmental area (VTA). LHA Gal neurons are sufficient to drive motivated feeding and locomotor activity similar to LHA GABA neurons, but without inducing compulsive-like behaviors, which we propose to require direct VTA innervation. Our study integrates galanin-expressing LHA neurons into our current understanding of the neuronal circuits and molecular mechanisms of the LHA that contribute to motivated feeding behaviors. Copyright © 2017 the authors 0270-6474/17/376053-13$15.00/0.

Serum-induced neurite retraction in CAD cells--involvement of an ATP-actin retractile system and the lack of microtubule-associated proteins.

PubMed

Chesta, María E; Carbajal, Agustín; Arce, Carlos A; Bisig, Carlos G

2014-11-01

Cultured catecholamine-differentiated cells [which lack the microtubule-associated proteins (MAPs): MAP1B, MAP2, Tau, STOP, and Doublecortin] proliferate in the presence of fetal bovine serum, and, in its absence, cease dividing and generate processes similar to the neurites of normal neurons. The reintroduction of serum induces neurite retraction, and proliferation resumes. The neurite retraction process in catecholamine-differentiated cells was partially characterized in this study. Microtubules in the cells were found to be in a highly dynamic state, and tubulin in the microtubules consisted primarily of the tyrosinated and deacetylated isotypes. Increased levels of acetylated or Δ2-tubulin (which are normally absent) did not prevent serum-induced neurite retraction. Treatment of differentiated cells with lysophosphatidic acid or adenosine deaminase induced neurite retraction. Inhibition of Rho-associated protein kinase, ATP depletion and microfilament disruption each (individually) blocked serum-induced neurite retraction, suggesting that an ATP-dependent actomyosin system underlies the mechanism of neurite retraction. Nocodazole treatment induced neurite retraction, but this effect was blocked by pretreatment with the microtubule-stabilizing drug paclitaxel (Taxol). Paclitaxel did not prevent serum-induced or lysophosphatidic acid-induced retraction, suggesting that integrity of microtubules (despite their dynamic state) is necessary to maintain neurite elongation, and that paclitaxel-induced stabilization alone is not sufficient to resist the retraction force induced by serum. Transfection with green fluorescent protein-Tau conferred resistance to retraction caused by serum. We hypothesize that, in normal neurons (cultured or in vivo), MAPs are necessary not only to stabilize microtubules, but also to establish interactions with other cytoskeletal or membrane components to form a stable structure capable of resisting the retraction force. © 2014 FEBS.

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

Adamo, Maria Pilar; Zapata, Marta; Frey, Teryl K.

Congenital infection with rubella virus (RUB) leads to persistent infection and congenital defects and we showed previously that primary human fetal fibroblasts did not undergo apoptosis when infected with RUB, which could promote fetal virus persistence [Adamo, P., Asis, L., Silveyra, P., Cuffini, C., Pedranti, M., Zapata, M., 2004. Rubella virus does not induce apoptosis in primary human embryo fibroblasts cultures: a possible way of viral persistence in congenital infection. Viral Immunol. 17, 87-100]. To extend this observation, gene chip analysis was performed on a line of primary human fetal fibroblasts (10 weeks gestation) and a line of human adultmore » lung fibroblasts (which underwent apoptosis in response to RUB infection) to compare gene expression in infected and uninfected cells. A total of 632 and 516 genes were upregulated or downregulated in the infected fetal and adult cells respectively in comparison to uninfected cells, however only 52 genes were regulated in both cell types. Although the regulated genes were different, across functional gene categories the patterns of gene regulation were similar. In general, regulation of pro- and anti-apoptotic genes following infection appeared to favor apoptosis in the adult cells and lack of apoptosis in the fetal cells, however there was a greater relative expression of anti-apoptotic genes and reduced expression of pro-apoptotic genes in uninfected fetal cells versus uninfected adult cells and thus the lack of apoptosis in fetal cells following RUB infection was also due to the prevailing background of gene expression that is antagonistic to apoptosis. In support of this hypothesis, it was found that of a battery of five chemicals known to induce apoptosis, two induced apoptosis in the adult cells, but not in fetal cells, and two induced apoptosis more rapidly in the adult cells than in fetal cells (the fifth did not induce apoptosis in either). A robust interferon-stimulated gene response was induced following infection of both fetal and adult cells and many of the genes upregulated in both cell types were those involved in establishment of an antiviral state; this is the first demonstration of an interferon response at this early stage of human embryonic development. In both fetal and adult cells, interferon controlled but did not eliminate virus spread and apoptosis was not induced in infected fetal cells in the absence of interferon. In addition to the interferon response, chemokines were induced in both infected fetal and adult cells. Thus, it is possible that fetal damage following congenital RUB infection, which involves cell proliferation and differentiation, could be due to induction of the innate immune response as well as frank virus infection.« less

Methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and 3,4-methylenedioxypyrovalerone (MDPV) induce differential cytotoxic effects in bovine brain microvessel endothelial cells.

PubMed

Rosas-Hernandez, Hector; Cuevas, Elvis; Lantz, Susan M; Rice, Kenner C; Gannon, Brenda M; Fantegrossi, William E; Gonzalez, Carmen; Paule, Merle G; Ali, Syed F

2016-08-26

Designer drugs such as synthetic psychostimulants are indicative of a worldwide problem of drug abuse and addiction. In addition to methamphetamine (METH), these drugs include 3,4-methylenedioxy-methamphetamine (MDMA) and commercial preparations of synthetic cathinones including 3,4-methylenedioxypyrovalerone (MDPV), typically referred to as "bath salts." These psychostimulants exert neurotoxic effects by altering monoamine systems in the brain. Additionally, METH and MDMA adversely affect the integrity of the blood-brain barrier (BBB): there are no current reports on the effects of MDPV on the BBB. The aim of this study was to compare the effects of METH, MDMA and MDPV on bovine brain microvessel endothelial cells (bBMVECs), an accepted in vitro model of the BBB. Confluent bBMVEC monolayers were treated with METH, MDMA and MDPV (0.5mM-2.5mM) for 24h. METH and MDMA increased lactate dehydrogenase release only at the highest concentration (2.5mM), whereas MDPV induced cytotoxicity at all concentrations. MDMA and METH decreased cellular proliferation only at 2.5mM, with similar effects observed after MDPV exposures starting at 1mM. Only MDPV increased reactive oxygen species production at all concentrations tested whereas all 3 drugs increased nitric oxide production. Morphological analysis revealed different patterns of compound-induced cell damage. METH induced vacuole formation at 1mM and disruption of the monolayer at 2.5mM. MDMA induced disruption of the endothelial monolayer from 1mM without vacuolization. On the other hand, MDPV induced monolayer disruption at doses ≥0.5mM without vacuole formation; at 2.5mM, the few remaining cells lacked endothelial morphology. These data suggest that even though these synthetic psychostimulants alter monoaminergic systems, they each induce BBB toxicity by different mechanisms with MDPV being the most toxic. Published by Elsevier Ireland Ltd.

THE EMBRYOLETHALITY OF LIPOPOLYSACCHARIDE IN CD-1 AND METALLOTHIONEIN I-II NULL MICE: LACK OF A ROLE FOR INDUCED ZINC DEFICIENCY OR METALLOTHIONEIN INDUCTION

EPA Science Inventory

ABSTRACT

Lipopolysaccharide (LPS) is embryolethal in CD-1 mice. LPS induces metallothionein (MT) via cytokines, including TNF-, IL-1 and IL-6, which initiate and maintain the acute phase response. Maternal hepatic MT induction in pregnant rats, by diverse toxicants, can ...

TRANSCRIPTOMIC ANALYSIS OF F344 RAT NASAL EPITHELIUM SUGGESTS THAT THE LACK OF CARCINOGENIC RESPONSE TO GLUTARALDEHYDE IS DUE TO ITS GREATER TOXICITY COMPARED TO FORMALDEHYDE

EPA Science Inventory

Formaldehyde is cytotoxic and carcinogenic to the rat nasal respiratory epithelium inducing tumors after 12 months. Glutaraldehyde is also cytotoxic but is not carcinogenic to nasal epithelium even after 24 months. Both aldehydes induce similar acute and subchronic histopathology...

The Availability of Information on Induced Lactation in Malaysia.

PubMed

Rahim, Norsyamlina Che Abdul; Sulaiman, Zaharah; Ismail, Tengku Alina Tengku

2017-08-01

Induced lactation is a method of stimulating the production of breast milk in women who have not gone through the process of pregnancy. Recent advances in technology have given such women the opportunity to breastfeed adopted children. Previous studies conducted in Western countries have explored the breastfeeding of adopted children, as well as the experiences, successes and challenges of this process. However, research on procedures for breastfeeding adopted children is lacking in Malaysia. The authors have therefore reviewed literature related to induced lactation in Malaysia to fill this gap. Of the 30 related articles identified, 19 described the breastfeeding practices and experiences of adoptive mothers in Malaysia. Out of 19 articles, there were four journal articles, five circulars and regulations, two books, two post-graduate theses, four blogs posts and forum discussions, and two online newspaper articles. Medical information relating to induced lactation procedures was also reviewed, showing that there was a lack of scientific studies focusing on induced lactation practices among adoptive mothers. Information on religious, specifically Islamic, perspectives on breastfeeding and child adoption laws was gathered from websites, social networks, blogs, magazines and online news sources. In consideration of recent advancements in medical technology and the dire need among Malaysians, it is crucial that evidence-based, accurate and reliable information on induced lactation is made available to professionals and other individuals in this country.

The Availability of Information on Induced Lactation in Malaysia

PubMed Central

Rahim, Norsyamlina Che Abdul; Sulaiman, Zaharah; Ismail, Tengku Alina Tengku

2017-01-01

Induced lactation is a method of stimulating the production of breast milk in women who have not gone through the process of pregnancy. Recent advances in technology have given such women the opportunity to breastfeed adopted children. Previous studies conducted in Western countries have explored the breastfeeding of adopted children, as well as the experiences, successes and challenges of this process. However, research on procedures for breastfeeding adopted children is lacking in Malaysia. The authors have therefore reviewed literature related to induced lactation in Malaysia to fill this gap. Of the 30 related articles identified, 19 described the breastfeeding practices and experiences of adoptive mothers in Malaysia. Out of 19 articles, there were four journal articles, five circulars and regulations, two books, two post-graduate theses, four blogs posts and forum discussions, and two online newspaper articles. Medical information relating to induced lactation procedures was also reviewed, showing that there was a lack of scientific studies focusing on induced lactation practices among adoptive mothers. Information on religious, specifically Islamic, perspectives on breastfeeding and child adoption laws was gathered from websites, social networks, blogs, magazines and online news sources. In consideration of recent advancements in medical technology and the dire need among Malaysians, it is crucial that evidence-based, accurate and reliable information on induced lactation is made available to professionals and other individuals in this country. PMID:28951685

Targeted mutagenesis in Atlantic salmon (Salmo salar L.) using the CRISPR/Cas9 system induces complete knockout individuals in the F0 generation.

PubMed

Edvardsen, Rolf B; Leininger, Sven; Kleppe, Lene; Skaftnesmo, Kai Ove; Wargelius, Anna

2014-01-01

Understanding the biological function behind key proteins is of great concern in Atlantic salmon, both due to a high commercial importance and an interesting life history. Until recently, functional studies in salmonids appeared to be difficult. However, the recent discovery of targeted mutagenesis using the CRISPR/Cas9 (clustered regularly interspaced palindromic repeats/CRISPR-associated) system enables performing functional studies in Atlantic salmon to a great extent. We used the CRISPR/Cas9 system to target two genes involved in pigmentation, tyrosinase (tyr) and solute carrier family 45, member 2 (slc45a2). Embryos were assayed for mutation rates at the 17 somite stage, where 40 and 22% of all injected embryos showed a high degree of mutation induction for slc45a2 and tyr, respectively. At hatching this mutation frequency was also visible for both targeted genes, displaying a graded phenotype ranging from complete lack of pigmentation to partial loss and normal pigmentation. CRISPRslc45a2/Cas9 injected embryos showing a complete lack of pigmentation or just a few spots of pigments also lacked wild type sequences when assaying more than 80 (slc45a2) sequence clones from whole embryos. This indicates that CRISPR/Cas9 can induce double-allelic knockout in the F0 generation. However, types and frequency of indels might affect the phenotype. Therefore, the variation of indels was assayed in the graded pigmentation phenotypes produced by CRISPR/Cas9-slc45a2. The results show a tendency for fewer types of indels formed in juveniles completely lacking pigmentation compared to juveniles displaying partial pigmentation. Another interesting observation was a high degree of the same indel type in different juveniles. This study shows for the first time successful use of the CRISPR/Cas9 technology in a marine cold water species. Targeted double-allelic mutations were obtained and, though the level of mosaicism has to be considered, we demonstrate that F0 fish can be used for functional studies in Atlantic salmon.

Radiation-Induced Dedifferentiation of Head and Neck Cancer Cells Into Cancer Stem Cells Depends on Human Papillomavirus Status

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

Vlashi, Erina, E-mail: evlashi@mednet.ucla.edu; Jonsson Comprehensive Cancer Center at UCLA, Los Angeles, California; Chen, Allen M.

Purpose: To test the hypothesis that the radiation response of cancer stem cells (CSCs) in human papillomavirus (HPV)-positive and HPV-negative head and neck squamous cell carcinoma (HNSCC) differs and is not reflected in the radiation response of the bulk tumor populations, that radiation therapy (RT) can dedifferentiate non-stem HNSCC cells into CSCs, and that radiation-induced dedifferentiation depends on the HPV status. Methods and Materials: Records of a cohort of 162 HNSCC patients were reviewed, and their outcomes were correlated with their HPV status. Using a panel of HPV-positive and HPV-negative HNSCC cell lines expressing a reporter for CSCs, we characterized HPV-positivemore » and HPV-negative lines via flow cytometry, sphere-forming capacity assays in vitro, and limiting dilution assays in vivo. Non-CSCs were treated with different doses of radiation, and the dedifferentiation of non-CSCs into CSCs was investigated via flow cytometry and quantitative reverse transcription–polymerase chain reaction for re-expression of reprogramming factors. Results: Patients with HPV-positive tumors have superior overall survival and local–regional control. Human papillomavirus–positive HNSCC cell lines have lower numbers of CSCs, which inversely correlates with radiosensitivity. Human papillomavirus–negative HNSCC cell lines lack hierarchy owing to enhanced spontaneous dedifferentiation. Non-CSCs from HPV-negative lines show enhanced radiation-induced dedifferentiation compared with HPV-positive lines, and RT induced re-expression of Yamanaka reprogramming factors. Conclusions: Supporting the favorable prognosis of HPV-positive HNSCCs, we show that (1) HPV-positive HNSCCs have a lower frequency of CSCs; (2) RT can dedifferentiate HNSCC cells into CSCs; and (3) radiation-induced dedifferentiation depends on the HPV status of the tumor.« less

Comparable polyfunctionality of ectromelia virus- and vaccinia virus-specific murine T cells despite markedly different in vivo replication and pathogenicity.

PubMed

Hersperger, Adam R; Siciliano, Nicholas A; Eisenlohr, Laurence C

2012-07-01

Vaccinia virus (VACV) stimulates long-term immunity against highly pathogenic orthopoxvirus infection of humans (smallpox) and mice (mousepox [ectromelia virus {ECTV}]) despite the lack of a natural host-pathogen relationship with either of these species. Previous research revealed that VACV is able to induce polyfunctional CD8(+) T-cell responses after immunization of humans. However, the degree to which the functional profile of T cells induced by VACV is similar to that generated during natural poxvirus infection remains unknown. In this study, we monitored virus-specific T-cell responses following the dermal infection of C57BL/6 mice with ECTV or VACV. Using polychromatic flow cytometry, we measured levels of degranulation, cytokine expression (gamma interferon [IFN-γ], tumor necrosis factor alpha [TNF-α], and interleukin-2 [IL-2]), and the cytolytic mediator granzyme B. We observed that the functional capacities of T cells induced by VACV and ECTV were of a similar quality in spite of the markedly different replication abilities and pathogenic outcomes of these viruses. In general, a significant fraction (≥50%) of all T-cell responses were positive for at least three functions both during acute infection and into the memory phase. In vivo killing assays revealed that CD8(+) T cells specific for both viruses were equally cytolytic (∼80% target cell lysis after 4 h), consistent with the similar levels of granzyme B and degranulation detected among these cells. Collectively, these data provide a mechanism to explain the ability of VACV to induce protective T-cell responses against pathogenic poxviruses in their natural hosts and provide further support for the use of VACV as a vaccine platform able to induce polyfunctional T cells.

Two enzymatic reaction pathways in the formation of pyropheophorbide a.

PubMed

Suzuki, Yasuyo; Doi, Michio; Shioi, Yuzo

2002-01-01

The demethoxycarbonyl reaction of pheophorbide a in plants and algae was investigated. Two types of enzyme that catalyze alternative reactions in the formation of pyropheophorbide a were found. One enzyme, designated 'pheophorbidase (Phedase)', was purified nearly to homogeneity from cotyledons of radish (Raphanus sativus). This enzyme catalyzes the conversion of pheophorbide a to a precursor of pyropheophorbide a, C-13(2)-carboxylpyropheophorbide a, by demethylation, and then the precursor is decarboxylated non-enzymatically to yield pyropheophorbide a. The activity of Phedase was inhibited by the reaction product, methanol. The other enzyme, termed 'pheophorbide demethoxycarbonylase (PDC)', was highly purified from the Chl b-less mutant NL-105 of Chlamydomonas reinhardtii. This enzyme had produced no intermediate as shown in the Phedase reaction, indicating that it converts pheophorbide a directly into pyropheophorbide a, probably by nucleophilic reaction. Phedase and PDC consisted of both senescence-induced and constitutive enzymes. The molecular weight of both Phedases was 113 000 and of senescence-induced PDC was 170 000. The K (m) values against pheophorbide a for both Phedases were 14-15 muM and 283 muM for senescence-induced PDC. The activity of both Phedases was inhibited by the reaction product, methanol, whereas methanol had no specific effect on senescence-induced PDC. Phenylmethylsulfonic fluoride and N-ethylmaleimide inhibited the senescence-induced Phedase and PDC, respectively. Among the 23 species from 15 different families tested, Phedase activity was found in 10 species from three families. PDC activity was not detected in plants lacking Phedase activity, except for Chlamydomonas. Based on these findings, a likely conclusion is that at least two alternative pathways that are catalyzed by two different enzymes, Phedase and PDC, exist for the formation of pyropheophorbide a.

A Comparison of Independent Event-Related Desynchronization Responses in Motor-Related Brain Areas to Movement Execution, Movement Imagery, and Movement Observation.

PubMed

Duann, Jeng-Ren; Chiou, Jin-Chern

2016-01-01

Electroencephalographic (EEG) event-related desynchronization (ERD) induced by movement imagery or by observing biological movements performed by someone else has recently been used extensively for brain-computer interface-based applications, such as applications used in stroke rehabilitation training and motor skill learning. However, the ERD responses induced by the movement imagery and observation might not be as reliable as the ERD responses induced by movement execution. Given that studies on the reliability of the EEG ERD responses induced by these activities are still lacking, here we conducted an EEG experiment with movement imagery, movement observation, and movement execution, performed multiple times each in a pseudorandomized order in the same experimental runs. Then, independent component analysis (ICA) was applied to the EEG data to find the common motor-related EEG source activity shared by the three motor tasks. Finally, conditional EEG ERD responses associated with the three movement conditions were computed and compared. Among the three motor conditions, the EEG ERD responses induced by motor execution revealed the alpha power suppression with highest strengths and longest durations. The ERD responses of the movement imagery and movement observation only partially resembled the ERD pattern of the movement execution condition, with slightly better detectability for the ERD responses associated with the movement imagery and faster ERD responses for movement observation. This may indicate different levels of involvement in the same motor-related brain circuits during different movement conditions. In addition, because the resulting conditional EEG ERD responses from the ICA preprocessing came with minimal contamination from the non-related and/or artifactual noisy components, this result can play a role of the reference for devising a brain-computer interface using the EEG ERD features of movement imagery or observation.

Effect of Vitamin E on Oxaliplatin-induced Peripheral Neuropathy Prevention: A Randomized Controlled Trial

PubMed Central

Salehi, Zeinab; Roayaei, Mahnaz

2015-01-01

Background: Peripheral neuropathy is one of the most important limitations of oxaliplatin base regimen, which is the standard for the treatment of colorectal cancer. Evidence has shown that Vitamin E may be protective in chemotherapy-induced peripheral neuropathy. The aim of this study is to evaluate the effect of Vitamin E administration on prevention of oxaliplatin-induced peripheral neuropathy in patients with colorectal cancer. Methods: This was a prospective randomized, controlled clinical trial. Patients with colorectal cancer and scheduled to receive oxaliplatin-based regimens were enrolled in this study. Enrolled patients were randomized into two groups. The first group received Vitamin E at a dose of 400 mg daily and the second group observed, until after the sixth course of the oxaliplatin regimen. For oxaliplatin-induced peripheral neuropathy assessment, we used the symptom experience diary questionnaire that completed at baseline and after the sixth course of chemotherapy. Only patients with a score of zero at baseline were eligible for this study. Results: Thirty-two patients were randomized to the Vitamin E group and 33 to the control group. There was no difference in the mean peripheral neuropathy score changes (after − before) between two groups, after sixth course of the oxaliplatin base regimen (mean difference [after − before] of Vitamin E group = 6.37 ± 2.85, control group = 6.57 ± 2.94; P = 0.78). Peripheral neuropathy scores were significantly increased after intervention compared with a base line in each group (P < 0.001). Conclusions: The results from this current trial demonstrate a lack of benefit for Vitamin E in preventing oxaliplatin-induced peripheral neuropathy. PMID:26682028

Social preference and maternal defeat-induced social avoidance in virgin female rats: sex differences in involvement of brain oxytocin and vasopressin.

PubMed

Lukas, Michael; Neumann, Inga D

2014-08-30

Research concerning non-reproductive sociability in rodents is mainly restricted to assessing the effects of oxytocin (OXT) and arginine-vasopressin (AVP) in male rats and mice. Comparable studies on natural social preference and social avoidance in females are substantially lacking. Here, we adapted a behavioral paradigm for monitoring social preference of female rats consisting of two consecutive exposures to either non-social or social stimuli. Further, to induce stimulus-specific social avoidance, female rats were exposed to a single 10-min maternal defeat by a lactating dam. Social preference towards same-sex conspecifics in female rats was shown to be independent of the estrous cycle and even more pronounced than in male rats. Intracerebroventricular (icv) application of OXT, AVP, or their selective receptor antagonists or agonists, did not alter naturally-occurring social preference in female rats. Stimulus-specific social avoidance could be induced by prior exposure to a lactating rat: an effect that could not be reversed/overcome by icv OXT. The female social preference paradigm for rats established in this study detected subtle sex differences in social preference behavior of rats. Further, stimulus-specific social deficits could be induced in female rats using an acute exposure to social defeat - as previously observed in male rodents. Female rats show strong social preference behavior, which can be prevented by social defeat, but does not seem to be regulated by the OXT or AVP systems. Accordingly, icv application of synthetic OXT does not reverse maternal defeat-induced social avoidance in female rats. Copyright © 2014 Elsevier B.V. All rights reserved.

Radiation-Induced Dedifferentiation of Head and Neck Cancer Cells Into Cancer Stem Cells Depends on Human Papillomavirus Status.

PubMed

Vlashi, Erina; Chen, Allen M; Boyrie, Sabrina; Yu, Garrett; Nguyen, Andrea; Brower, Philip A; Hess, Clayton B; Pajonk, Frank

2016-04-01

To test the hypothesis that the radiation response of cancer stem cells (CSCs) in human papillomavirus (HPV)-positive and HPV-negative head and neck squamous cell carcinoma (HNSCC) differs and is not reflected in the radiation response of the bulk tumor populations, that radiation therapy (RT) can dedifferentiate non-stem HNSCC cells into CSCs, and that radiation-induced dedifferentiation depends on the HPV status. Records of a cohort of 162 HNSCC patients were reviewed, and their outcomes were correlated with their HPV status. Using a panel of HPV-positive and HPV-negative HNSCC cell lines expressing a reporter for CSCs, we characterized HPV-positive and HPV-negative lines via flow cytometry, sphere-forming capacity assays in vitro, and limiting dilution assays in vivo. Non-CSCs were treated with different doses of radiation, and the dedifferentiation of non-CSCs into CSCs was investigated via flow cytometry and quantitative reverse transcription-polymerase chain reaction for re-expression of reprogramming factors. Patients with HPV-positive tumors have superior overall survival and local-regional control. Human papillomavirus-positive HNSCC cell lines have lower numbers of CSCs, which inversely correlates with radiosensitivity. Human papillomavirus-negative HNSCC cell lines lack hierarchy owing to enhanced spontaneous dedifferentiation. Non-CSCs from HPV-negative lines show enhanced radiation-induced dedifferentiation compared with HPV-positive lines, and RT induced re-expression of Yamanaka reprogramming factors. Supporting the favorable prognosis of HPV-positive HNSCCs, we show that (1) HPV-positive HNSCCs have a lower frequency of CSCs; (2) RT can dedifferentiate HNSCC cells into CSCs; and (3) radiation-induced dedifferentiation depends on the HPV status of the tumor. Copyright © 2016 Elsevier Inc. All rights reserved.

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

Wang, Yiwei; Gulis, Galina; Buckner, Scott

Research highlights: {yields} Rotenone induces generation of ROS and mitochondrial fragmentation in fission yeast. {yields} The MAPK Pmk1 and PKA are required for rotenone resistance in fission yeast. {yields} Pmk1 and PKA are required for ROS clearance in rotenone treated fission yeast cells. {yields} PKA plays a role in ROS clearance under normal growth conditions in fission yeast. -- Abstract: Rotenone is a widely used pesticide that induces Parkinson's disease-like symptoms in rats and death of dopaminergic neurons in culture. Although rotenone is a potent inhibitor of complex I of the mitochondrial electron transport chain, it can induce death ofmore » dopaminergic neurons independently of complex I inhibition. Here we describe effects of rotenone in the fission yeast, Schizosaccharomyces pombe, which lacks complex I and carries out rotenone-insensitive cellular respiration. We show that rotenone induces generation of reactive oxygen species (ROS) as well as fragmentation of mitochondrial networks in treated S. pombe cells. While rotenone is only modestly inhibitory to growth of wild type S. pombe cells, it is strongly inhibitory to growth of mutants lacking the ERK-type MAP kinase, Pmk1, or protein kinase A (PKA). In contrast, cells lacking the p38 MAP kinase, Spc1, exhibit modest resistance to rotenone. Consistent with these findings, we provide evidence that Pmk1 and PKA, but not Spc1, are required for clearance of ROS in rotenone treated S. pombe cells. Our results demonstrate the usefulness of S. pombe for elucidating complex I-independent molecular targets of rotenone as well as mechanisms conferring resistance to the toxin.« less

Primary vascularization of allografts governs their immunogenicity and susceptibility to tolerogenesis

PubMed Central

Kant, Cavit D.; Akiyama, Yoshinobu; Tanaka, Katsunori; Shea, Susan; Connolly, Sarah E; Germana, Sharon; Winn, Henry J.; LeGuern, Christian; Tocco, Georges; Benichou, Gilles

2013-01-01

We investigated the influence of allograft primary vascularization on alloimmunity, rejection and tolerance in mice. First, we showed that fully allogeneic primarily vascularized and conventional skin transplants were rejected at the same pace. Remarkably, however, short-term treatment of mice with anti-CD40L antibodies achieved long-term survival of vascularized skin and cardiac transplants but not conventional skin grafts. Non-vascularized skin transplants triggered vigorous direct and indirect pro-inflammatory type 1 T cell responses (IL-2 and γIFN) while primarily-vascularized skin allografts failed to trigger a significant indirect alloresponse. Similar lack of indirect alloreactivity was also observed after placement of different vascularized organ transplants including hearts and kidneys while hearts placed under the skin (non-vascularized) triggers potent indirect alloresponses. Altogether, these results suggest that primary vascularization of allografts is associated with lack of indirect T cell alloreactivity. Finally, we show that long-term survival of vascularized skin allografts induced by anti-CD40L antibodies was associated with a combined lack of indirect alloresponse and a shift of the direct alloresponse towards a type 2 cytokine (IL-4, IL-10) secretion pattern but no activation/expansion of regulatory T cells. Therefore, primary vascularization of allografts governs their immunogenicity and tolerogenicity. PMID:23833234

Lack of ecto-5'-nucleotidase (CD73) promotes arteriogenesis.

PubMed

Böring, Yang Chul; Flögel, Ulrich; Jacoby, Christoph; Heil, Matthias; Schaper, Wolfgang; Schrader, Jürgen

2013-01-01

Adenosine can stimulate angiogenesis, but its role in the distinct process of arteriogenesis is unknown. We have previously reported that mice lacking ecto-5'-nucleotidase (CD73-/-) show enhanced monocyte adhesion to the endothelium after ischaemia, which is considered to be an important trigger for arteriogenesis. Hindlimb ischaemia was induced in wild-type (WT) and CD73-/- mice to study the role of extracellularly formed adenosine in arteriogenesis. Magnetic resonance angiography (MRA) was performed for serial visualization of newly developed vessels at a spatial resolution of 1 nL, and high-energy phosphates (HEP) were quantified by (31)P MR spectroscopy (MRS). MRA of CD73-/- mice revealed substantially enhanced collateral artery conductance at day 7 [CD73-/-: 0.73 ± 0.11 a.u. (arbitrary units); WT: 0.44 ± 0.13 a.u.; P < 0.01, n = 6], and MRS of the affected hindlimb showed a faster restoration of HEP in correlation with enhanced functional recovery in the mutant. Additionally, histology showed no differences in capillary density between the groups but showed an increased monocyte infiltration in hindlimbs of CD73-/- mice. Serial assessment of dynamic changes of vessel growth and metabolism in the process of arteriogenesis demonstrate that the lack of CD73-derived adenosine importantly promotes arteriogenesis but does not alter angiogenesis in our model of hindlimb ischaemia.

Human-gyrovirus-Apoptin triggers mitochondrial death pathway--Nur77 is required for apoptosis triggering.

PubMed

Chaabane, Wiem; Cieślar-Pobuda, Artur; El-Gazzah, Mohamed; Jain, Mayur V; Rzeszowska-Wolny, Joanna; Rafat, Mehrdad; Stetefeld, Joerg; Ghavami, Saeid; Los, Marek J

2014-09-01

The human gyrovirus derived protein Apoptin (HGV-Apoptin) a homologue of the chicken anemia virus Apoptin (CAV-Apoptin), a protein with high cancer cells selective toxicity, triggers apoptosis selectively in cancer cells. In this paper, we show that HGV-Apoptin acts independently from the death receptor pathway as it induces apoptosis in similar rates in Jurkat cells deficient in either FADD (fas-associated death domain) function or caspase-8 (key players of the extrinsic pathway) and their parental clones. HGV-Apoptin induces apoptosis via the activation of the mitochondrial intrinsic pathway. It induces both mitochondrial inner and outer membrane permebilization, characterized by the loss of the mitochondrial potential and the release into cytoplasm of the pro-apoptotic molecules including apoptosis inducing factor and cytochrome c. HGV-Apoptin acts via the apoptosome, as lack of expression of apoptotic protease-activating factor 1 in murine embryonic fibroblast strongly protected the cells from HGV-Apoptin-induced apoptosis. Moreover, QVD-oph a broad-spectrum caspase inhibitor delayed HGV-Apoptin-induced death. On the other hand, overexpression of the anti-apoptotic BCL-XL confers resistance to HGV-Apoptin-induced cell death. In contrast, cells that lack the expression of the pro-apoptotic BAX and BAK are protected from HGV-Apoptin induced apoptosis. Furthermore, HGV-Apoptin acts independently from p53 signal but triggers the cytoplasmic translocation of Nur77. Taking together these data indicate that HGV-Apoptin acts through the mitochondrial pathway, in a caspase-dependent manner but independently from the death receptor pathway. Copyright © 2014 Neoplasia Press, Inc. Published by Elsevier Inc. All rights reserved.

Characterization of root agravitropism induced by genetic, chemical, and developmental constraints

NASA Technical Reports Server (NTRS)

Moore, R.; Fondren, W. M.; Marcum, H.

1987-01-01

The patterns and rates of organelle redistribution in columella (i.e., putative statocyte) cells of agravitropic agt mutants of Zea mays are not significantly different from those of columella cells in graviresponsive roots. Graviresponsive roots of Z. mays are characterized by a strongly polar movement of 45Ca2+ across the root tip from the upper to the lower side. Horizontally-oriented roots of agt mutants exhibit only a minimal polar transport of 45Ca2+. Exogenously-induced asymmetries of Ca result in curvature of agt roots toward the Ca source. A similar curvature can be induced by a Ca asymmetry in normally nongraviresponsive (i.e., lateral) roots of Phaseolus vulgaris. Similarly, root curvature can be induced by placing the roots perpendicular to an electric field. This electrotropism increased with 1) currents between 8-35 mA, and 2) time between 1-9 hr when the current is constant. Electrotropism is reduced significantly by treating roots with triiodobenzoic acid (TIBA), an inhibitor of auxin transport. These results suggest that 1) if graviperception occurs via the sedimentation of amyloplasts in columella cells, then nongraviresponsive roots apparently sense gravity as do graviresponsive roots, 2) exogenously-induced asymmetries of a gravitropic effector (i.e., Ca) can induce curvature of normally nongraviresponsive roots, 3) the gravity-induced downward movement of exogenously-applied 45Ca2+ across tips of graviresponsive roots does not occur in nongraviresponsive roots, 4) placing roots in an electrical field (i.e., one favoring the movement of ions such as Ca2+) induces root curvature, and 5) electrically-induced curvature is apparently dependent on auxin transport. These results are discussed relative to a model to account for the lack of graviresponsiveness by these roots.

Deletion of vanilloid receptor (TRPV1) in mice alters behavioral effects of ethanol

PubMed Central

Blednov, Y.A.; Harris, R.A.

2009-01-01

The vanilloid receptor TRPV1 is activated by ethanol and this may be important for some of the central and peripheral actions of ethanol. To determine if this receptor has a role in ethanol-mediated behaviors, we studied null mutant mice in which the Trpv1 gene was deleted. Mice lacking this gene showed significantly higher preference for ethanol and consumed more ethanol in a two-bottle choice test as compared with wild type littermates. Null mutant mice showed shorter duration of loss of righting reflex induced by low doses of ethanol (3.2 and 3.4 g/kg) and faster recovery from motor incoordination induced by ethanol (2 g/kg). However, there were no differences between null mutant and wild type mice in severity of ethanol-induced acute withdrawal (4 g/kg) or conditioned taste aversion to ethanol (2.5 g/kg). Two behavioral phenotypes (decreased sensitivity to ethanol-induced sedation and faster recovery from ethanol-induced motor incoordination) seen in null mutant mice were reproduced in wild type mice by injection of a TRPV1 antagonist, capsazepine (10 mg/kg). These two ethanol behaviors were changed in the opposite direction after injection of capsaicin, a selective TRPV1 agonist, in wild type mice. The studies provide the first evidence that TRPV1 is important for specific behavioral actions of ethanol. PMID:19705551

Capsaicin Induces Autophagy and Apoptosis in Human Nasopharyngeal Carcinoma Cells by Downregulating the PI3K/AKT/mTOR Pathway.

PubMed

Lin, Yu-Tsai; Wang, Hung-Chen; Hsu, Yi-Chiang; Cho, Chung-Lung; Yang, Ming-Yu; Chien, Chih-Yen

2017-06-23

Capsaicin is a potential chemotherapeutic agent for different human cancers. In Southeast China, nasopharyngeal carcinoma (NPC) has the highest incidence of all cancers, but final treatment outcomes are unsatisfactory. However, there is a lack of information regarding the anticancer activity of capsaicin in NPC cells, and its effects on the signaling transduction pathways related to apoptosis and autophagy remain unclear. In the present study, the precise mechanisms by which capsaicin exerts anti-proliferative effects, cell cycle arrest, autophagy and apoptosis were investigated in NPC-TW01 cells. Exposure to capsaicin inhibited cancer cell growth and increased G1 phase cell cycle arrest. Western blotting and quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR) were used to measure capsaicin-induced autophagy via involvement of the class III PI3K/Beclin-1/Bcl-2 signaling pathway. Capsaicin induced autophagy by increasing levels of the autophagy markers LC3-II and Atg5, enhancing p62 and Fap-1 degradation and increasing caspase-3 activity to induce apoptosis, suggesting a correlation of blocking the PI3K/Akt/mTOR pathway with the above-mentioned anticancer activities. Taken together, these data confirm that capsaicin inhibited the growth of human NPC cells and induced autophagy, supporting its potential as a therapeutic agent for cancer.

The NLP toxin family in Phytophthora sojae includes rapidly evolving groups that lack necrosis-inducing activity.

PubMed

Dong, Suomeng; Kong, Guanghui; Qutob, Dinah; Yu, Xiaoli; Tang, Junli; Kang, Jixiong; Dai, Tingting; Wang, Hai; Gijzen, Mark; Wang, Yuanchao

2012-07-01

Necrosis- and ethylene-inducing-like proteins (NLP) are widely distributed in eukaryotic and prokaryotic plant pathogens and are considered to be important virulence factors. We identified, in total, 70 potential Phytophthora sojae NLP genes but 37 were designated as pseudogenes. Sequence alignment of the remaining 33 NLP delineated six groups. Three of these groups include proteins with an intact heptapeptide (Gly-His-Arg-His-Asp-Trp-Glu) motif, which is important for necrosis-inducing activity, whereas the motif is not conserved in the other groups. In total, 19 representative NLP genes were assessed for necrosis-inducing activity by heterologous expression in Nicotiana benthamiana. Surprisingly, only eight genes triggered cell death. The expression of the NLP genes in P. sojae was examined, distinguishing 20 expressed and 13 nonexpressed NLP genes. Real-time reverse-transcriptase polymerase chain reaction results indicate that most NLP are highly expressed during cyst germination and infection stages. Amino acid substitution ratios (Ka/Ks) of 33 NLP sequences from four different P. sojae strains resulted in identification of positive selection sites in a distinct NLP group. Overall, our study indicates that expansion and pseudogenization of the P. sojae NLP family results from an ongoing birth-and-death process, and that varying patterns of expression, necrosis-inducing activity, and positive selection suggest that NLP have diversified in function.

Nonautophagic cytoplasmic vacuolation death induction in human PC-3M prostate cancer by curcumin through reactive oxygen species -mediated endoplasmic reticulum stress

PubMed Central

Lee, Wei-Jiunn; Chien, Ming-Hsien; Chow, Jyh-Ming; Chang, Junn-Liang; Wen, Yu-Ching; Lin, Yung-Wei; Cheng, Chao-Wen; Lai, Gi-Ming; Hsiao, Michael; Lee, Liang-Ming

2015-01-01

The antiapoptotic and antiautophagic abilities of cancer cells constitute a major challenge for anticancer drug treatment. Strategies for triggering nonapoptotic or nonautophagic cell death may improve therapeutic efficacy against cancer. Curcumin has been reported to exhibit cancer chemopreventive properties. Herein, we report that curcumin induced apoptosis in LNCaP, DU145, and PC-3 cells but triggered extensive cytoplasmic vacuolation in PC-3M cells. Electron microscopic images showed that the vacuoles lacked intracellular organelles and were derived from the endoplasmic reticulum (ER). Moreover, curcumin-induced vacuolation was not reversed by an apoptosis- or autophagy-related inhibitor, suggesting that vacuolation-mediated cell death differs from classical apoptotic and autophagic cell death. Mechanistic investigations revealed that curcumin treatment upregulated the ER stress markers CHOP and Bip/GRP78 and the autophagic marker LC3-II. In addition, curcumin induced ER stress by triggering ROS generation, which was supported by the finding that treating cells with the antioxidant NAC alleviated curcumin-mediated ER stress and vacuolation-mediated death. An in vivo PC-3M orthotopic prostate cancer model revealed that curcumin reduced tumor growth by inducing ROS production followed by vacuolation-mediated cell death. Overall, our results indicated that curcumin acts as an inducer of ROS production, which leads to nonapoptotic and nonautophagic cell death via increased ER stress. PMID:26013662

Mice lacking glutamate carboxypeptidase II develop normally, but are less susceptible to traumatic brain injury.

PubMed

Gao, Yang; Xu, Siyi; Cui, Zhenwen; Zhang, Mingkun; Lin, Yingying; Cai, Lei; Wang, Zhugang; Luo, Xingguang; Zheng, Yan; Wang, Yong; Luo, Qizhong; Jiang, Jiyao; Neale, Joseph H; Zhong, Chunlong

2015-07-01

Glutamate carboxypeptidase II (GCPII) is a transmembrane zinc metallopeptidase found mainly in the nervous system, prostate and small intestine. In the nervous system, glia-bound GCPII mediates the hydrolysis of the neurotransmitter N-acetylaspartylglutamate (NAAG) into glutamate and N-acetylaspartate. Inhibition of GCPII has been shown to attenuate excitotoxicity associated with enhanced glutamate transmission under pathological conditions. However, different strains of mice lacking the GCPII gene are reported to exhibit striking phenotypic differences. In this study, a GCPII gene knockout (KO) strategy involved removing exons 3-5 of GCPII. This generated a new GCPII KO mice line with no overt differences in standard neurological behavior compared to their wild-type (WT) littermates. However, GCPII KO mice were significantly less susceptible to moderate traumatic brain injury (TBI). GCPII gene KO significantly lessened neuronal degeneration and astrocyte damage in the CA2 and CA3 regions of the hippocampus 24 h after moderate TBI. In addition, GCPII gene KO reduced TBI-induced deficits in long-term spatial learning/memory tested in the Morris water maze and motor balance tested via beam walking. Knockout of the GCPII gene is not embryonic lethal and affords histopathological protection with improved long-term behavioral outcomes after TBI, a result that further validates GCPII as a target for drug development consistent with results from studies using GCPII peptidase inhibitors. © 2015 International Society for Neurochemistry.

DPP8/9 inhibition induces pro-caspase-1-dependent monocyte and macrophage pyroptosis

PubMed Central

Okondo, Marian C.; Johnson, Darren C.; Sridharan, Ramya; Go, Eun Bin; Chui, Ashley J.; Wang, Mitchell S.; Poplawski, Sarah E.; Wu, Wengen; Liu, Yuxin; Lai, Jack H.; Sanford, David G.; Arciprete, Michael O.; Golub, Todd R.; Bachovchin, William W.; Bachovchin, Daniel A.

2017-01-01

Val-boroPro (talabostat, PT-100), a nonselective inhibitor of post-proline cleaving serine proteases, stimulates mammalian immune systems through an unknown mechanism of action. Despite this lack of mechanistic understanding, Val-boroPro has attracted significant interest as a potential anticancer agent, reaching Phase III trials in humans. Here we show that Val-boroPro stimulates the immune system by triggering a proinflammatory form of cell death in monocytes and macrophages known as pyroptosis. We demonstrate that the inhibition of two serine proteases, DPP8 and DPP9, activates the proprotein form of caspase-1 independent of the inflammasome adaptor ASC. Activated pro-caspase-1 does not efficiently process itself or IL-1β, but does cleave and activate gasdermin D to induce pyroptosis. Mice lacking caspase-1 do not show immune stimulation after treatment with Val-boroPro. Our data identifies the first small molecule that induces pyroptosis and reveals a new checkpoint that controls the activation of the innate immune system. PMID:27820798

Adsorption induced enzyme denaturation: the role of protein surface in adsorption induced protein denaturation on allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) copolymers.

PubMed

Thudi, Lahari; Jasti, Lakshmi S; Swarnalatha, Y; Fadnavis, Nitin W; Mulani, Khudbudin; Deokar, Sarika; Ponrathnam, Surendra

2012-02-01

The effects of protein size on adsorption and adsorption-induced denaturation of proteins on copolymers of allyl glycidyl ether (AGE)-ethylene glycol dimethacrylate (EGDM) have been studied. Different responses were observed for the amount of protein adsorbed and denatured on the polymer surface for different proteins (trypsin, alchol dehydrogenase from baker's yeast (YADH), glucose dehydrogenase (GDH) from Gluconobacter cerinus, and alkaline phosphates from calf intestinal mucosa (CIAP). Protein adsorption on the copolymer with 25% crosslink density (AGE-25) was dependent not only on the size of the protein but also on the presence of glycoside residues on the protein surface. Adsorption and denaturation of proteins follows the order YADH>trypsin>GDH>CIAP although the molecular weights of the proteins follow the order YADH>CIAP>GDH>trypsin. The lack of correlation between amount of adsorbed protein and its molecular weight was due to the presence of glycoside residues on CIAP and GDH which protect the enzyme surface from denaturation. Enzyme stabilities in aqueous solutions of 1-cyclohexyl-2-pyrrolidinone (CHP) correlate well with the trend in denaturation by the copolymer, strongly suggesting that hydrophobic interactions play a major role in protein binding and the mechanism of protein denaturation is similar to that for water-miscible organic solvents. Copyright © 2011 Elsevier B.V. All rights reserved.

Vasodilator therapy with hydralazine induces angiotensin AT2 receptor-mediated cardiomyocyte growth in mice lacking guanylyl cyclase-A

PubMed Central

Li, Y; Saito, Y; Kuwahara, K; Rong, X; Kishimoto, I; Harada, M; Horiuchi, M; Murray, M; Nakao, K

2010-01-01

Background and purpose: Recent clinical guidelines advocate the use of the isosorbide dinitrate/hydralazine combination in treatment for heart failure. However, clinical and laboratory evidence suggest that some vasodilators may induce cardiac hypertrophy under uncertain conditions. This study investigated the effects and underlying mechanism of action of the vasodilator hydralazine on cardiac growth. Experimental approach: Wild-type mice and animals deficient in guanylyl cyclase-A (GCA) and/or angiotensin receptors (AT1 and AT2 subtypes) were treated with hydralazine (≈24 mg·kg−1·day−1 in drinking water) for 5 weeks. Cardiac mass and/or cardiomyocyte cross-sectional area, fibrosis (van Giessen-staining) and cardiac gene expression (real-time RT-PCR) were measured. Key results: Hydralazine lowered blood pressure in mice of all genotypes. However, this treatment increased the heart and left ventricular to body weight ratios, as well as cardiomyocyte cross-sectional area, and cardiac expression of atrial natriuretic peptide mRNA in mice lacking GCA. Hydralazine did not affect cardiac hypertrophy in wild-type mice and mice lacking either AT1 or AT2 receptors alone. However, the pro-hypertrophic effect of hydralazine was prevented in mice lacking both GCA and AT2, but not GCA and AT1 receptors. However, hydralazine did decrease cardiac collagen deposition and collagen I mRNA (signs of cardiac fibrosis) in mice that were deficient in GCA, or both GCA and AT2 receptors. Conclusions and implications: The vasodilator hydralazine induced AT2 receptor-mediated cardiomyocyte growth under conditions of GCA deficiency. However, attenuation of cardiac fibrosis by hydralazine could be beneficial in the management of cardiac diseases. PMID:20136844

Prophylactic and therapeutic vaccination with carrier-bound Bet v 1 peptides lacking allergen-specific T cell epitopes reduces Bet v 1-specific T cell responses via blocking antibodies in a murine model for birch pollen allergy.

PubMed

Linhart, B; Narayanan, M; Focke-Tejkl, M; Wrba, F; Vrtala, S; Valenta, R

2014-02-01

Vaccines consisting of allergen-derived peptides lacking IgE reactivity and allergen-specific T cell epitopes bound to allergen-unrelated carrier molecules have been suggested as candidates for allergen-specific immunotherapy. To study whether prophylactic and therapeutic vaccination with carrier-bound peptides from the major birch pollen allergen Bet v 1 lacking allergen-specific T cell epitopes has influence on Bet v 1-specific T cell responses. Three Bet v 1-derived peptides, devoid of Bet v 1-specific T cell epitopes, were coupled to KLH and adsorbed to aluminium hydroxide to obtain a Bet v 1-specific allergy vaccine. Groups of BALB/c mice were immunized with the peptide vaccine before or after sensitization to Bet v 1. Bet v 1- and peptide-specific antibody responses were analysed by ELISA. T cell and cytokine responses to Bet v 1, KLH, and the peptides were studied in proliferation assays. The effects of peptide-specific and allergen-specific antibodies on T cell responses and allergic lung inflammation were studied using specific antibodies. Prophylactic and therapeutic vaccination with carrier-bound Bet v 1 peptides induced a Bet v 1-specific IgG antibody response without priming/boosting of Bet v 1-specific T cells. Prophylactic and therapeutic vaccination of mice with the peptide vaccine induced Bet v 1-specific antibodies which suppressed Bet v 1-specific T cell responses and allergic lung inflammation. Vaccination with carrier-bound allergen-derived peptides lacking allergen-specific T cell epitopes induces allergen-specific IgG antibodies which suppress allergen-specific T cell responses and allergic lung inflammation. © 2013 John Wiley & Sons Ltd.

Lack of Inducible NO Synthase Reduces Oxidative Stress and Enhances Cardiac Response to Isoproterenol in Mice With Deoxycorticosterone Acetate–Salt Hypertension

PubMed Central

Sun, Ying; Carretero, Oscar A.; Xu, Jiang; Rhaleb, Nour-Eddine; Wang, Fangfei; Lin, Chunxia; Yang, James J.; Pagano, Patrick J.; Yang, Xiao-Ping

2015-01-01

Although NO derived from endothelial NO synthase (eNOS) is thought to be cardioprotective, the role of inducible NO synthase (iNOS) remains controversial. Using mice lacking iNOS (iNOS−/−), we studied (1) whether development of hypertension, cardiac hypertrophy, and dysfunction after deoxycorticosterone acetate (DOCA)–salt would be less severe compared with wild-type controls (WT; C57BL/6J), and (2) whether the cardioprotection attributable to lack of iNOS is mediated by reduced oxidative stress. Mice were uninephrectomized and received either DOCA-salt (30 mg/mouse SC and 1% NaCl+0.2% KCl in drinking water) or vehicle (tap water) for 12 weeks. Systolic blood pressure (SBP) was measured weekly. Left ventricular (LV) ejection fraction (EF) by echocardiography and cardiac response to isoproterenol (50 ng/mouse IV) were studied at the end of the experiment. Expression of eNOS and iNOS as well as the oxidative stress markers 4-hydroxy-2-nonenal (4-HNE, a marker of lipid peroxidation) and nitrotyrosine (a marker for peroxynitrite) were determined by Western blot and immunohistochemical staining, respectively. DOCA-salt increased SBP and LV weight similarly in both strains and decreased EF in WT but not in iNOS−/−. Cardiac contractile and relaxation responses to isoproterenol were greater, 4-HNE and nitrotyrosine levels were lower, and eNOS expression tended to be higher in iNOS−/−. We conclude that lack of iNOS leads to better preservation of cardiac function, which may be mediated by reduced oxidative stress and increased eNOS; however, it does not seem to play a significant role in preventing DOCA-salt–induced hypertension and hypertrophy. PMID:16286571

A critical literature review of focused electron beam induced deposition

NASA Astrophysics Data System (ADS)

van Dorp, W. F.; Hagen, C. W.

2008-10-01

An extensive review is given of the results from literature on electron beam induced deposition. Electron beam induced deposition is a complex process, where many and often mutually dependent factors are involved. The process has been studied by many over many years in many different experimental setups, so it is not surprising that there is a great variety of experimental results. To come to a better understanding of the process, it is important to see to which extent the experimental results are consistent with each other and with the existing model. All results from literature were categorized by sorting the data according to the specific parameter that was varied (current density, acceleration voltage, scan patterns, etc.). Each of these parameters can have an effect on the final deposit properties, such as the physical dimensions, the composition, the morphology, or the conductivity. For each parameter-property combination, the available data are discussed and (as far as possible) interpreted. By combining models for electron scattering in a solid, two different growth regimes, and electron beam induced heating, the majority of the experimental results were explained qualitatively. This indicates that the physical processes are well understood, although quantitatively speaking the models can still be improved. The review makes clear that several major issues remain. One issue encountered when interpreting results from literature is the lack of data. Often, important parameters (such as the local precursor pressure) are not reported, which can complicate interpretation of the results. Another issue is the fact that the cross section for electron induced dissociation is unknown. In a number of cases, a correlation between the vertical growth rate and the secondary electron yield was found, which suggests that the secondary electrons dominate the dissociation rather than the primary electrons. Conclusive evidence for this hypothesis has not been found. Finally, there is a limited understanding of the mechanism of electron induced precursor dissociation. In many cases, the deposit composition is not directly dependent on the stoichiometric composition of the precursor and the electron induced decomposition paths can be very different from those expected from calculations or thermal decomposition. The dissociation mechanism is one of the key factors determining the purity of the deposits and a better understanding of this process will help develop electron beam induced deposition into a viable nanofabrication technique.

Acid Sphingomyelinase Gene Knockout Ameliorates Hyperhomocysteinemic Glomerular Injury in Mice Lacking Cystathionine-β-Synthase

PubMed Central

Boini, Krishna M.; Xia, Min; Abais, Justine M.; Xu, Ming; Li, Cai-xia; Li, Pin-Lan

2012-01-01

Acid sphingomyelinase (ASM) has been implicated in the development of hyperhomocysteinemia (hHcys)-induced glomerular oxidative stress and injury. However, it remains unknown whether genetically engineering of ASM gene produces beneficial or detrimental action on hHcys-induced glomerular injury. The present study generated and characterized the mice lacking cystathionine β-synthase (Cbs) and Asm mouse gene by cross breeding Cbs+/− and Asm+/− mice. Given that the homozygotes of Cbs−/−/Asm−/− mice could not survive for 3 weeks. Cbs+/−/Asm+/+, Cbs+/−/Asm+/− and Cbs+/−/Asm−/− as well as their Cbs wild type littermates were used to study the role of Asm−/− under a background of Cbs+/− with hHcys. HPLC analysis revealed that plasma Hcys level was significantly elevated in Cbs heterozygous (Cbs+/−) mice with different copies of Asm gene compared to Cbs+/+ mice with different Asm gene copies. Cbs+/−/Asm+/+ mice had significantly increased renal Asm activity, ceramide production and O2.− level compared to Cbs+/+/Asm+/+, while Cbs+/−/Asm−/− mice showed significantly reduced renal Asm activity, ceramide production and O2.− level due to increased plasma Hcys levels. Confocal microscopy demonstrated that colocalization of podocin with ceramide was much lower in Cbs+/−/Asm−/− mice compared to Cbs+/−/Asm+/+ mice, which was accompanied by a reduced glomerular damage index, albuminuria and proteinuria in Cbs+/−/Asm−/− mice. Immunofluorescent analyses of the podocin, nephrin and desmin expression also illustrated less podocyte damages in the glomeruli from Cbs+/−/Asm−/− mice compared to Cbs+/−/Asm+/+ mice. In in vitro studies of podocytes, hHcys-enhanced O2.− production, desmin expression, and ceramide production as well as decreases in VEGF level and podocin expression in podocytes were substantially attenuated by prior treatment with amitriptyline, an Asm inhibitor. In conclusion, Asm gene knockout or corresponding enzyme inhibition protects the podocytes and glomeruli from hHcys-induced oxidative stress and injury. PMID:23024785

Thrombospondin-2 Expression During Retinal Vascular Development and Neovascularization.

PubMed

Fei, Ping; Palenski, Tammy L; Wang, Shoujian; Gurel, Zafer; Hankenson, Kurt D; Sorenson, Christine M; Sheibani, Nader

2015-09-01

To determine thrombospondin-2 (TSP2) expression and its impact on postnatal retinal vascular development and retinal neovascularization. The TSP2-deficient (TSP2(-/-)) mice and a line of TSP2 reporter mice were used to assess the expression of TSP2 during postnatal retinal vascular development and neovascularization. The postnatal retinal vascularization was evaluated using immunostaining of wholemount retinas prepared at different postnatal days by collagen IV staining and/or TSP2 promoter driven green fluorescent protein (GFP) expression. The organization of astrocytes was evaluated by glial fibrillary acidic protein (GFAP) staining. Retinal vascular densities were determined using trypsin digestion preparation of wholemount retinas at 3- and 6-weeks of age. Retinal neovascularization was assessed during the oxygen-induced ischemic retinopathy (OIR). Choroidal neovascularization (CNV) was assessed using laser-induced CNV. Using the TSP2-GFP reporter mice, we observed significant expression of TSP2 mRNA in retinas of postnatal day 5 (P5) mice, which increased by P7 and remained high up to P42. Similar results were observed in retinal wholemount preparations, and western blotting for GFP with the highest level of GFP was observed at P21. In contrast to high level of mRNA at P42, the GFP fluorescence or protein level was dramatically downregulated. The primary retinal vasculature developed at a faster rate in TSP2(-/-) mice compared with TSP2(+/+) mice up to P5. However, the developing retinal vasculature in TSP2(+/+) mice caught up with that of TSP2(-/-) mice after P7. No significant differences in retinal vascular density were observed at 3- or 6-weeks of age. TSP2(-/-) mice also exhibited a similar sensitivity to the hyperoxia-mediated vessel obliteration and similar level of neovascularization during OIR as TSP2(+/+) mice. Lack of TSP2 expression minimally affected laser-induced CNV compared with TSP2(+/+) mice. Lack of TSP2 expression was associated with enhanced retinal vascularization during early postnatal days but not at late postnatal times, and minimally affected retinal and CNV. However, the utility of TSP2 as a potential therapeutic target for inhibition of ocular neovascularization awaits further investigation.

Unfolding DNA condensates produced by DNA-like charged depletants: A force spectroscopy study

NASA Astrophysics Data System (ADS)

Lima, C. H. M.; Rocha, M. S.; Ramos, E. B.

2017-02-01

In this work, we have measured, by means of optical tweezers, forces acting on depletion-induced DNA condensates due to the presence of the DNA-like charged protein bovine serum albumin (BSA). The stretching and unfolding measurements performed on the semi-flexible DNA chain reveal (1) the softening of the uncondensed DNA contour length and (2) a mechanical behavior strikingly different from those previously observed: the force-extension curves of BSA-induced DNA condensates lack the "saw-tooth" pattern and applied external forces as high as ≈80 pN are unable to fully unfold the condensed DNA contour length. This last mechanical experimental finding is in agreement with force-induced "unpacking" detailed Langevin dynamics simulations recently performed by Cortini et al. on model rod-like shaped condensates. Furthermore, a simple thermodynamics analysis of the unfolding process has enabled us to estimate the free energy involved in the DNA condensation: the estimated depletion-induced interactions vary linearly with both the condensed DNA contour length and the BSA concentration, in agreement with the analytical and numerical analysis performed on model DNA condensates. We hope that future additional experiments can decide whether the rod-like morphology is the actual one we are dealing with (e.g. pulling experiments coupled with super-resolution fluorescence microscopy).

Autophagy inducers in cancer.

PubMed

Russo, Maria; Russo, Gian Luigi

2018-07-01

Autophagy is a complex, physiological process devoted to degrade and recycle cellular components. Proteins and organelles are first phagocytized by autophagosomes, then digested in lysosomes, and finally recycled to be utilized again during cellular metabolism. Moreover, autophagy holds an important role in the physiopathology of several diseases. In cancer, excellent works demonstrated the dual functions of autophagy in tumour biology: autophagy activation can promote cancer cells survival (protective autophagy), or contribute to cancer cell death (cytotoxic/nonprotective autophagy). A better understanding of the dichotomy roles of autophagy in cancer biology can help to identify or design new drugs able to induce/enhance (or block) autophagic flux. These features will necessary be tissue-dependent and confined to a specific time of treatment. The intent of this review is to focus on the different potentialities of autophagy inducers in cancer prevention versus therapy in order to elicit a desirable clinical response. Few promising synthetic and natural compounds have been identified and the pros and cons of their role in autophagy regulation is reviewed here. In the complex framework of autophagy modulation, "connecting the dots" is not a simple work and the lack of clinical studies further complicates the scenario, but the final goal to obtain clinically relevant autophagy inducers can reveal an unexpected landscape. Copyright © 2018 Elsevier Inc. All rights reserved.

Red wine induced modulation of vascular function: separating the role of polyphenols, ethanol, and urates.

PubMed

Boban, Mladen; Modun, Darko; Music, Ivana; Vukovic, Jonatan; Brizic, Ivica; Salamunic, Ilza; Obad, Ante; Palada, Ivan; Dujic, Zeljko

2006-05-01

By using red wine (RW), dealcoholized red wine (DARW), polyphenols-stripped red wine (PSRW), ethanol-water solution (ET), and water (W), the role of wine polyphenols, ethanol, and urate on vascular function was examined in humans (n = 9 per beverage) and on isolated rat aortic rings (n = 9). Healthy males randomly consumed each beverage in a cross-over design. Plasma ethanol, catechin, and urate concentrations were measured before and 30, 60 and 120 minutes after beverage intake. Endothelial function was assessed before and 60 minutes after beverage consumption by normalized flow-mediated dilation (FMD). RW and DARW induced similar vasodilatation in the isolated vessels whereas PSRW, ET, and W did not. All ethanol-containing beverages induced similar basal vasodilatation of brachial artery. Only intake of RW resulted in enhancement of endothelial response, despite similar plasma catechin concentration after DARW. The borderline effect of RW on FMD (P = 0.0531) became significant after FMD normalization (P = 0.0043) that neutralized blunting effect of ethanol-induced basal vasodilatation. Effects of PSRW and ET did not differ although plasma urate increased after PSRW and not after ET, indicating lack of urate influence on endothelial response. Acute vascular effects of RW, mediated by polyphenols, cannot be predicted by plasma catechin concentration only.

The effect of polarized light on the organization of collagen secreted by fibroblasts.

PubMed

Akilbekova, Dana; Boddupalli, Anuraag; Bratlie, Kaitlin M

2018-04-01

Recent studies have demonstrated the beneficial effect of low-power lasers and polarized light on wound healing, inflammation, and the treatment of rheumatologic and neurologic disorders. The overall effect of laser irradiation treatment is still controversial due to the lack of studies on the biochemical mechanisms and the optimal parameters for the incident light that should be chosen for particular applications. Here, we study how NIH/3T3 fibroblasts respond to irradiation with linearly polarized light at different polarization angles. In particular, we examined vascular endothelial growth factor (VEGF) secretion, differentiation to myofibroblasts, and collagen organization in response to 800 nm polarized light at 0°, 45°, 90°, and 135° with a power density of 40 mW/cm 2 for 6 min every day for 6 days. Additional experiments were conducted in which the polarization angle of the incident was changed every day to induce an isotropic distribution of collagen. The data presented here shows that polarized light can upregulate VEGF production, myofibroblast differentiation, and induce different collagen organization in response to different polarization angles of the incident beam. These results are encouraging and demonstrate possible methods for controlling cell response through the polarization angle of the laser light, which has potential for the treatment of wounds.

Memory retrieval of smoking-related images induce greater insula activation as revealed by an fMRI based delayed matching to sample task

PubMed Central

Janes, AC; Ross, RS; Farmer, S; Frederick, BB; Nickerson, L; Lukas, SE; Stern, CE

2013-01-01

Nicotine dependence is a chronic and difficult to treat disorder. While environmental stimuli associated with smoking precipitate craving and relapse, it is unknown whether smoking cues are cognitively processed differently than neutral stimuli. To evaluate working memory differences between smoking-related and neutral stimuli, we conducted a delay-match-to-sample (DMS) task concurrently with functional magnetic resonance imaging (fMRI) in nicotine dependent participants. The DMS task evaluates brain activation during the encoding, maintenance, and retrieval phases of working memory. Smoking images induced significantly more subjective craving, and greater midline cortical activation during encoding in comparison to neutral stimuli that were similar in content yet lacked a smoking component. The insula, which is involved in maintaining nicotine dependence, was active during the successful retrieval of previously viewed smoking vs. neutral images. In contrast, neutral images required more prefrontal cortex-mediated active maintenance during the maintenance period. These findings indicate that distinct brain regions are involved in the different phases of working memory for smoking-related vs. neutral images. Importantly the results implicate the insula in the retrieval of smoking-related stimuli, which is relevant given the insula’s emerging role in addiction. PMID:24261848

Memory retrieval of smoking-related images induce greater insula activation as revealed by an fMRI-based delayed matching to sample task.

PubMed

Janes, Amy C; Ross, Robert S; Farmer, Stacey; Frederick, Blaise B; Nickerson, Lisa D; Lukas, Scott E; Stern, Chantal E

2015-03-01

Nicotine dependence is a chronic and difficult to treat disorder. While environmental stimuli associated with smoking precipitate craving and relapse, it is unknown whether smoking cues are cognitively processed differently than neutral stimuli. To evaluate working memory differences between smoking-related and neutral stimuli, we conducted a delay-match-to-sample (DMS) task concurrently with functional magnetic resonance imaging (fMRI) in nicotine-dependent participants. The DMS task evaluates brain activation during the encoding, maintenance and retrieval phases of working memory. Smoking images induced significantly more subjective craving, and greater midline cortical activation during encoding in comparison to neutral stimuli that were similar in content yet lacked a smoking component. The insula, which is involved in maintaining nicotine dependence, was active during the successful retrieval of previously viewed smoking versus neutral images. In contrast, neutral images required more prefrontal cortex-mediated active maintenance during the maintenance period. These findings indicate that distinct brain regions are involved in the different phases of working memory for smoking-related versus neutral images. Importantly, the results implicate the insula in the retrieval of smoking-related stimuli, which is relevant given the insula's emerging role in addiction. © 2013 Society for the Study of Addiction.

Technical note: a pilot study using a mouse mastitis model to study differences between bovine associated coagulase-negative staphylococci.

PubMed

Breyne, K; De Vliegher, S; De Visscher, A; Piepers, S; Meyer, E

2015-02-01

Coagulase-negative staphylococci (CNS) are a group of bacteria classified as either minor mastitis pathogens or commensal microbiota. Recent research suggests species- and even strain-related epidemiological and genetic differences within the large CNS group. The current pilot study investigated in 2 experiments whether a mouse mastitis model validated for bovine Staphylococcus aureus can be used to explore further differences between CNS species and strains. In a first dose titration experiment, a low inoculum dose of S. aureus Newbould 305 (positive control) was compared with increasing inoculum doses of a Staphylococcus chromogenes strain originating from a chronic bovine intramammary infection to a sham-inoculated mammary glands (negative control). In contrast to the high bacterial growth following inoculation with S. aureus, S. chromogenes was retrieved in very low levels at 24 h postinduction (p.i.). In a second experiment, the inflammation inflicted by 3 CNS strains was studied in mice. The host immune response induced by the S. chromogenes intramammary strain was compared with the one induced by a Staphylococcus fleurettii strain originating from cow bedding sawdust and by a S. chromogenes strain originating from a teat apex of a heifer. As expected, at 28 and 48 h p.i., low bacterial growth and local neutrophil influx in the mammary gland were induced by all CNS strains. As hypothesized, bacterial growth p.i. was the lowest for S. fleurettii compared with that induced by the 2 S. chromogenes strains, and the overall immune response established by the 3 CNS strains was less pronounced compared with the one induced by S. aureus. Proinflammatory cytokine profiling revealed that S. aureus locally induced IL-6 and IL-1β but not TNF-α, whereas, overall, CNS-inoculated glands lacked a strong cytokine host response but also induced IL-1β locally. Compared with both other CNS strains, S. chromogenes from the teat apex inflicted a more variable IL-1β response characterized by a more intense local reaction in several mice. This pilot study suggests that an intraductal mouse model can mimic bovine CNS mastitis and has potential as a complementary in vivo tool for future CNS mastitis research. Furthermore, it indicates that epidemiologically different bovine CNS species or strains induce a differential host innate immune response in the murine mammary gland. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

A Review of Differences in Clinical Characteristics between Tardive Syndrome Induced or Improved by Aripiprazole Treatment.

PubMed

Chen, Yen-Wen; Tseng, Ping-Tao

2016-09-15

Tardive syndrome is a troublesome complication secondary to the long-term usage of antipsychotic medication. At present, there is a lack of effective treatment for tardive syndrome. Aripiprazole has been used in the treatment of tardive syndrome, with some reports of a good response. However, other reports have suggested that tardive syndrome can actually be induced by aripiprazole. The aim of current study was to investigate whether aripiprazole is beneficial or harmful for the treatment of tardive syndrome in specific patients. We performed a thorough literature search via PubMed. We included all of the studies discussing the relationship between tardive syndrome and aripiprazole, either with regards to "inducing" or "improving" the disease. None of the included studies were well-designed clinical trials, and all were case reports or case series. A total of 26 articles were included in which aripiprazole induced tardive syndrome, and another 24 in which tardive syndrome was improved by aripiprazole treatment. In the "improved" group, there were significantly more cases of schizophrenia than in the "induced" group (p=0.002). However, there were significantly more cases with other miscellaneous diagnoses in the "induced" group than in the "improved" group (p=0.003). In addition, the cases in the "induced" group had a significantly longer duration of aripiprazole usage than those in the "improved" group (p=0.001). Current study is important for clinicians to pay attention to the risk of tardive syndrome when prescribing aripiprazole in patients with a diagnosis other than a psychiatric illness or in the long-term administration of aripiprazole.

Economic Impact of Hearing Loss and Reduction of Noise-Induced Hearing Loss in the United States

ERIC Educational Resources Information Center

Neitzel, Richard L.; Swinburn, Tracy K.; Hammer, Monica S.; Eisenberg, Daniel

2017-01-01

Purpose: Hearing loss (HL) is pervasive and debilitating, and noise-induced HL is preventable by reducing environmental noise. Lack of economic analyses of HL impacts means that prevention and treatment remain a low priority for public health and environmental investment. Method: This article estimates the costs of HL on productivity by building…

Effect of the environment on the dendritic morphology of the rat auditory cortex

PubMed Central

Bose, Mitali; Muñoz-Llancao, Pablo; Roychowdhury, Swagata; Nichols, Justin A.; Jakkamsetti, Vikram; Porter, Benjamin; Byrapureddy, Rajasekhar; Salgado, Humberto; Kilgard, Michael P.; Aboitiz, Francisco; Dagnino-Subiabre, Alexies; Atzori, Marco

2010-01-01

The present study aimed to identify morphological correlates of environment-induced changes at excitatory synapses of the primary auditory cortex (A1). We used the Golgi-Cox stain technique to compare pyramidal cells dendritic properties of Sprague-Dawley rats exposed to different environmental manipulations. Sholl analysis, dendritic length measures, and spine density counts were used to monitor the effects of sensory deafness and an auditory version of environmental enrichment (EE). We found that deafness decreased apical dendritic length leaving basal dendritic length unchanged, whereas EE selectively increased basal dendritic length without changing apical dendritic length. On the contrary, deafness decreased while EE increased spine density in both basal and apical dendrites of A1 layer 2/3 (LII/III) neurons. To determine whether stress contributed to the observed morphological changes in A1, we studied neural morphology in a restraint-induced model that lacked behaviorally relevant acoustic cues. We found that stress selectively decreased apical dendritic length in the auditory but not in the visual primary cortex. Similar to the acoustic manipulation, stress-induced changes in dendritic length possessed a layer specific pattern displaying LII/III neurons from stressed animals with normal apical dendrites but shorter basal dendrites, while infragranular neurons (layers V and VI) displayed shorter apical dendrites but normal basal dendrites. The same treatment did not induce similar changes in the visual cortex, demonstrating that the auditory cortex is an exquisitely sensitive target of neocortical plasticity, and that prolonged exposure to different acoustic as well as emotional environmental manipulation may produce specific changes in dendritic shape and spine density. PMID:19771593

Comparison of photo- and thermally initiated polymerization-induced self-assembly: a lack of end group fidelity drives the formation of higher order morphologies† †Electronic supplementary information (ESI) available: Additional NMR spectra, SEC, TEM and DLS data as well as histograms for the PEG113–PHPMA400 formulations and MALDI-ToF data for the oligomer study. See DOI: 10.1039/c7py00407a

PubMed Central

Blackman, Lewis D.; Doncom, Kay E. B.

2017-01-01

Polymerization-induced self-assembly (PISA) is an emerging industrially relevant technology, which allows the preparation of defined and predictable polymer self-assemblies with a wide range of morphologies. In recent years, interest has turned to photoinitiated PISA processes, which show markedly accelerated reaction kinetics and milder conditions, thereby making it an attractive alternative to thermally initiated PISA. Herein, we attempt to elucidate the differences between these two initiation methods using isothermally derived phase diagrams of a well-documented poly(ethylene glycol)-b-(2-hydroxypropyl methacrylate) (PEG-b-HPMA) PISA system. By studying the influence of the intensity of the light source used, as well as an investigation into the thermodynamically favorable morphologies, the factors dictating differences in the obtained morphologies when comparing photo- and thermally initiated PISA were explored. Our findings indicate that differences in a combination of both reaction kinetics and end group fidelity led to the observed discrepencies between the two techniques. We find that the loss of the end group in photoinitiated PISA drives the formation of higher order structures and that a morphological transition from worms to unilamellar vesicles could be induced by extended periods of light and heat irradiation. Our findings demonstrate that PISA of identical block copolymers by the two different initiation methods can lead to structures that are both chemically and morphologically distinct. PMID:29225706

Size- and coating-dependent cytotoxicity and genotoxicity of silver nanoparticles evaluated using in vitro standard assays.

PubMed

Guo, Xiaoqing; Li, Yan; Yan, Jian; Ingle, Taylor; Jones, Margie Yvonne; Mei, Nan; Boudreau, Mary D; Cunningham, Candice K; Abbas, Mazhar; Paredes, Angel M; Zhou, Tong; Moore, Martha M; Howard, Paul C; Chen, Tao

2016-11-01

The physicochemical characteristics of silver nanoparticles (AgNPs) may greatly alter their toxicological potential. To explore the effects of size and coating on the cytotoxicity and genotoxicity of AgNPs, six different types of AgNPs, having three different sizes and two different coatings, were investigated using the Ames test, mouse lymphoma assay (MLA) and in vitro micronucleus assay. The genotoxicities of silver acetate and silver nitrate were evaluated to compare the genotoxicity of nanosilver to that of ionic silver. The Ames test produced inconclusive results for all types of the silver materials due to the high toxicity of silver to the test bacteria and the lack of entry of the nanoparticles into the cells. Treatment of L5718Y cells with AgNPs and ionic silver resulted in concentration-dependent cytotoxicity, mutagenicity in the Tk gene and the induction of micronuclei from exposure to nearly every type of the silver materials. Treatment of TK6 cells with these silver materials also resulted in concentration-dependent cytotoxicity and significantly increased micronucleus frequency. With both the MLA and micronucleus assays, the smaller the AgNPs, the greater the cytotoxicity and genotoxicity. The coatings had less effect on the relative genotoxicity of AgNPs than the particle size. Loss of heterozygosity analysis of the induced Tk mutants indicated that the types of mutations induced by AgNPs were different from those of ionic silver. These results suggest that AgNPs induce cytotoxicity and genotoxicity in a size- and coating-dependent manner. Furthermore, while the MLA and in vitro micronucleus assay (in both types of cells) are useful to quantitatively measure the genotoxic potencies of AgNPs, the Ames test cannot.

Brain damage resulting from postnatal hypoxic-ischemic brain injury is reduced in C57BL/6J mice as compared to C57BL/6N mice.

PubMed

Wolf, S; Hainz, N; Beckmann, A; Maack, C; Menger, M D; Tschernig, T; Meier, C

2016-11-01

Perinatal hypoxia is a critical complication during delivery and is mostly studied in animal models of postnatal hypoxic-ischemic brain injury. We here studied the effects of postnatal hypoxic-ischemic brain injury in two different sub-strains of C57BL/6 mice, i.e. C57BL/6J and C57BL/6N mice. These two sub-strains show different metabolic properties, for instance an impaired glucose tolerance in C57BL/6J mice. Genetically, this was linked to differences in their nicotinamide nucleotide transhydrogenase (Nnt) genes: In C57BL/6J mice, exons 7-11 of the Nnt gene are deleted, resulting in the absence of functional Nnt protein. The mitochondrial Nnt-protein is one of several enzymes that catalyses the generation of NADPH, which in turn is important for the elimination of reactive oxygen species (ROS). As ROS is thought to contribute to the pathophysiology of hypoxia-ischemia, the lack of Nnt might indirectly increase ROS levels and therefore result in increased brain damage. We therefore hypothesize that lesion score and lesion size will increase in C57BL/6J mice as compared to C57BL/6N mice. Surprisingly, the results showed exactly the opposite: C57BL/6J mice showed a decrease in lesion score and size, associated with a reduced number of apoptotic cells and activated microglia. In contrast, the number of cells with ROS-induced DNA modifications (detected by 8OHdG) was higher in C57BL/6J than C57BL/6N mice. In conclusion, C57BL/6J mice showed reduced ischemic consequences after postnatal hypoxic-ischemic brain injury compared to C57BL/6N mice, with the exception of the amount of ROS-induced DNA-damage. These differences might relate to the lack of Nnt, but also to a modified metabolic setting (cardiovascular parameters, oxygen and glucose metabolism, immune function) in C57BL/6J mice. Copyright © 2016 Elsevier B.V. All rights reserved.

The C-terminal CGHC motif of protein disulfide isomerase supports thrombosis

PubMed Central

Zhou, Junsong; Wu, Yi; Wang, Lu; Rauova, Lubica; Hayes, Vincent M.; Poncz, Mortimer; Essex, David W.

2015-01-01

Protein disulfide isomerase (PDI) has two distinct CGHC redox-active sites; however, the contribution of these sites during different physiologic reactions, including thrombosis, is unknown. Here, we evaluated the role of PDI and redox-active sites of PDI in thrombosis by generating mice with blood cells and vessel wall cells lacking PDI (Mx1-Cre Pdifl/fl mice) and transgenic mice harboring PDI that lacks a functional C-terminal CGHC motif [PDI(ss-oo) mice]. Both mouse models showed decreased fibrin deposition and platelet accumulation in laser-induced cremaster arteriole injury, and PDI(ss-oo) mice had attenuated platelet accumulation in FeCl3-induced mesenteric arterial injury. These defects were rescued by infusion of recombinant PDI containing only a functional C-terminal CGHC motif [PDI(oo-ss)]. PDI infusion restored fibrin formation, but not platelet accumulation, in eptifibatide-treated wild-type mice, suggesting a direct role of PDI in coagulation. In vitro aggregation of platelets from PDI(ss-oo) mice and PDI-null platelets was reduced; however, this defect was rescued by recombinant PDI(oo-ss). In human platelets, recombinant PDI(ss-oo) inhibited aggregation, while recombinant PDI(oo-ss) potentiated aggregation. Platelet secretion assays demonstrated that the C-terminal CGHC motif of PDI is important for P-selectin expression and ATP secretion through a non-αIIbβ3 substrate. In summary, our results indicate that the C-terminal CGHC motif of PDI is important for platelet function and coagulation. PMID:26529254

Tectonic plates, D (double prime) thermal structure, and the nature of mantle plumes

NASA Technical Reports Server (NTRS)

Lenardic, A.; Kaula, W. M.

1994-01-01

It is proposed that subducting tectonic plates can affect the nature of thermal mantle plumes by determining the temperature drop across a plume source layer. The temperature drop affects source layer stability and the morphology of plumes emitted from it. Numerical models are presented to demonstrate how introduction of platelike behavior in a convecting temperature dependent medium, driven by a combination of internal and basal heating, can increase the temperature drop across the lower boundary layer. The temperature drop increases dramatically following introduction of platelike behavior due to formation of a cold temperature inversion above the lower boundary layer. This thermal inversion, induced by deposition of upper boundary layer material to the system base, decays in time, but the temperature drop across the lower boundary layer always remains considerably higher than in models lacking platelike behavior. On the basis of model-inferred boundary layer temperature drops and previous studies of plume dynamics, we argue that generally accepted notions as to the nature of mantle plumes on Earth may hinge on the presence of plates. The implication for Mars and Venus, planets apparently lacking plate tectonics, is that mantle plumes of these planets may differ morphologically from those of Earth. A corollary model-based argument is that as a result of slab-induced thermal inversions above the core mantle boundary the lower most mantle may be subadiabatic, on average (in space and time), if major plate reorganization timescales are less than those acquired to diffuse newly deposited slab material.

Communicating Low-Probability High-Consequence Risk, Uncertainty and Expert Confidence: Induced Seismicity of Deep Geothermal Energy and Shale Gas.

PubMed

Knoblauch, Theresa A K; Stauffacher, Michael; Trutnevyte, Evelina

2018-04-01

Subsurface energy activities entail the risk of induced seismicity including low-probability high-consequence (LPHC) events. For designing respective risk communication, the scientific literature lacks empirical evidence of how the public reacts to different written risk communication formats about such LPHC events and to related uncertainty or expert confidence. This study presents findings from an online experiment (N = 590) that empirically tested the public's responses to risk communication about induced seismicity and to different technology frames, namely deep geothermal energy (DGE) and shale gas (between-subject design). Three incrementally different formats of written risk communication were tested: (i) qualitative, (ii) qualitative and quantitative, and (iii) qualitative and quantitative with risk comparison. Respondents found the latter two the easiest to understand, the most exact, and liked them the most. Adding uncertainty and expert confidence statements made the risk communication less clear, less easy to understand and increased concern. Above all, the technology for which risks are communicated and its acceptance mattered strongly: respondents in the shale gas condition found the identical risk communication less trustworthy and more concerning than in the DGE conditions. They also liked the risk communication overall less. For practitioners in DGE or shale gas projects, the study shows that the public would appreciate efforts in describing LPHC risks with numbers and optionally risk comparisons. However, there seems to be a trade-off between aiming for transparency by disclosing uncertainty and limited expert confidence, and thereby decreasing clarity and increasing concern in the view of the public. © 2017 Society for Risk Analysis.

Reliability of Causality Assessment for Drug, Herbal and Dietary Supplement Hepatoxicity in the Drug-Induced Liver Injury Network (DILIN)

PubMed Central

Hayashi, Paul H.; Barnhart, Huiman X.; Fontana, Robert J.; Chalasani, Naga; Davern, Timothy J.; Talwalkar, Jayant A.; Reddy, K. Rajender; Stolz, Andrew A.; Hoofnagle, Jay H.; Rockey, Don C.

2014-01-01

Background Due to the lack of objective tests to diagnose drug induced liver injury (DILI), causality assessment is a matter of debate. Expert opinion is often used in research and industry but its test-retest reliability is unknown. Aims To determine the test-retest reliability of the expert opinion process used by the Drug-Induced Liver Injury Network (DILIN) Methods Three DILIN hepatologists adjudicate suspected hepatotoxicity cases to 1 of 5 categories representing levels of likelihood of DILI. Adjudication is based on retrospective assessment of gathered case data that includes prospective follow-up information. One hundred randomly selected DILIN cases were re-assessed using the same processes for initial assessment but by 3 different reviewers in 92% of cases. Results The median time between assessments was 938 days (range: 140–2352). Thirty-one cases involved >1 agent. Weighted kappa statistics for overall case and individual agent category agreement were 0.60 (95% CI: 0.50–0.71) and 0.60 (0.52–0.68), respectively. Overall case adjudications were within one category of each other 93% of the time, while 5% differed by 2 categories and 2% differed by 3 categories. Fourteen-percent crossed the 50% threshold of likelihood due to competing diagnoses or atypical timing between drug exposure and injury. Conclusions The DILIN expert opinion causality assessment method has moderate inter-observer reliability but very good agreement within 1 category. A small but important proportion of cases could not be reliably diagnosed as ≥ 50% likely to be DILI. PMID:24661785

Heavy Metals Induce Iron Deficiency Responses at Different Hierarchic and Regulatory Levels1[OPEN

PubMed Central

2017-01-01

In plants, the excess of several heavy metals mimics iron (Fe) deficiency-induced chlorosis, indicating a disturbance in Fe homeostasis. To examine the level at which heavy metals interfere with Fe deficiency responses, we carried out an in-depth characterization of Fe-related physiological, regulatory, and morphological responses in Arabidopsis (Arabidopsis thaliana) exposed to heavy metals. Enhanced zinc (Zn) uptake closely mimicked Fe deficiency by leading to low chlorophyll but high ferric-chelate reductase activity and coumarin release. These responses were not caused by Zn-inhibited Fe uptake via IRON-REGULATED TRANSPORTER (IRT1). Instead, Zn simulated the transcriptional response of typical Fe-regulated genes, indicating that Zn affects Fe homeostasis at the level of Fe sensing. Excess supplies of cobalt and nickel altered root traits in a different way from Fe deficiency, inducing only transient Fe deficiency responses, which were characterized by a lack of induction of the ethylene pathway. Cadmium showed a rather inconsistent influence on Fe deficiency responses at multiple levels. By contrast, manganese evoked weak Fe deficiency responses in wild-type plants but strongly exacerbated chlorosis in irt1 plants, indicating that manganese antagonized Fe mainly at the level of transport. These results show that the investigated heavy metals modulate Fe deficiency responses at different hierarchic and regulatory levels and that the interaction of metals with physiological and morphological Fe deficiency responses is uncoupled. Thus, this study not only emphasizes the importance of assessing heavy metal toxicities at multiple levels but also provides a new perspective on how Fe deficiency contributes to the toxic action of individual heavy metals. PMID:28500270

Schizophrenia and induced abortions: A national register-based follow-up study among Finnish women born between 1965-1980 with schizophrenia or schizoaffective disorder.

PubMed

Simoila, Laura; Isometsä, Erkki; Gissler, Mika; Suvisaari, Jaana; Sailas, Eila; Halmesmäki, Erja; Lindberg, Nina

2018-02-01

The objectives of this study were to investigate, in women with schizophrenia or schizoaffective disorder, the number and incidence of induced abortions (= pregnancy terminations performed by a physician), their demographic characteristics, use of contraceptives, plus indications of and complications related to pregnancy termination. Using the Care Register for Health Care, we identified Finnish women born between the years 1965-1980 who were diagnosed with either schizophrenia or schizoaffective disorder during the follow-up period ending 31.12.2013. For each case, five age- and place-of-birth- matched controls were obtained from the Population Register of Finland. Information about births and induced abortions were obtained from the Medical Birth Register and the Induced Abortion Register. The number and incidence of induced abortions per 1000 follow-up years did not differ between cases and their controls. However, due to fewer pregnancies, cases exhibited an over 2-fold increased risk of pregnancy termination (RR 2.28; 95% CI 2.20-2.36). Cases were younger, were more often without a partner at the time of induced abortion, and their pregnancies resulted more often from a lack of contraception. Among cases, the indication for pregnancy termination was more often mother-to-be's medical condition. Induced abortions after 12weeks gestation were more common among cases. However, cases had no more complications related to termination. The incidence of induced abortions among Finnish women with schizophrenia or schizoaffective disorder is similar to the general population, but their risk per pregnancy over two-fold. They need effective, affordable family planning services and long-term premeditated contraception. Copyright © 2017 Elsevier B.V. All rights reserved.

The use of bisphosphonates does not contraindicate orthodontic and other types of treatment!

PubMed Central

Consolaro, Alberto

2014-01-01

Bisphosphonates have been increasingly used not only to treat bone diseases as well as conditions such as osteopenia and osteoporosis, but also in oncotherapy. The use of bisphosphonates induces clinicians to fear and care. These reactions are associated with controversy resulting from lack of in-depth knowledge on the mechanisms of action as well as lack of a more accurate assessment of side effects. Scientific and clinical knowledge disclosure greatly contributes to professionals' discernment and inner balance, especially orthodontists. Fear does not lead to awareness. For these reasons, we present an article that focuses on that matter. This article was adapted from different journals of different dental specialties, as mentioned on footnote. There is no scientific evidence demonstrating that bisphosphonates are directly involved with etiopathogenic mechanisms of osteonecrosis and jaw osteomyelitis. Their use is contraindicated and limited in cases of dental treatment involving bone tissue. Nevertheless, such fact is based on professional opinion, case reports, and personal experience or experiment trials with failing methods. Additional studies will always be necessary; however, in-depth knowledge on bone biology is of paramount importance to offer an opinion about the clinical use of bisphosphonates and their further implications. Based on bone biopathology, this article aims at contributing to lay the groundwork for this matter. PMID:25279517

Estimating the Maximum Magnitude of Induced Earthquakes With Dynamic Rupture Simulations

NASA Astrophysics Data System (ADS)

Gilmour, E.; Daub, E. G.

2017-12-01

Seismicity in Oklahoma has been sharply increasing as the result of wastewater injection. The earthquakes, thought to be induced from changes in pore pressure due to fluid injection, nucleate along existing faults. Induced earthquakes currently dominate central and eastern United States seismicity (Keranen et al. 2016). Induced earthquakes have only been occurring in the central US for a short time; therefore, too few induced earthquakes have been observed in this region to know their maximum magnitude. The lack of knowledge regarding the maximum magnitude of induced earthquakes means that large uncertainties exist in the seismic hazard for the central United States. While induced earthquakes follow the Gutenberg-Richter relation (van der Elst et al. 2016), it is unclear if there are limits to their magnitudes. An estimate of the maximum magnitude of the induced earthquakes is crucial for understanding their impact on seismic hazard. While other estimates of the maximum magnitude exist, those estimates are observational or statistical, and cannot take into account the possibility of larger events that have not yet been observed. Here, we take a physical approach to studying the maximum magnitude based on dynamic ruptures simulations. We run a suite of two-dimensional ruptures simulations to physically determine how ruptures propagate. The simulations use the known parameters of principle stress orientation and rupture locations. We vary the other unknown parameters of the ruptures simulations to obtain a large number of rupture simulation results reflecting different possible sets of parameters, and use these results to train a neural network to complete the ruptures simulations. Then using a Markov Chain Monte Carlo method to check different combinations of parameters, the trained neural network is used to create synthetic magnitude-frequency distributions to compare to the real earthquake catalog. This method allows us to find sets of parameters that are consistent with earthquakes observed in Oklahoma and find which parameters effect the rupture propagation. Our results show that the stress orientation and magnitude, pore pressure, and friction properties combine to determine the final magnitude of the simulated event.

Cell Cycle Related Differentiation of Bone Marrow Cells into Lung Cells

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

Dooner, Mark; Aliotta, Jason M.; Pimental, Jeffrey

2007-12-31

Green-fluorescent protein (GFP) labeled marrow cells transplanted into lethally irradiated mice can be detected in the lungs of transplanted mice and have been shown to express lung specific proteins while lacking the expression of hematopoietic markers. We have studied marrow cells induced to transit cell cycle by exposure to IL-3, IL-6, IL-11 and steel factor at different times of culture corresponding to different phases of cell cycle. We have found that marrow cells at the G1/S interface have a 3-fold increase in cells which assume a lung phenotype and that this increase is no longer seen in late S/G2. Thesemore » cells have been characterized as GFP{sup +} CD45{sup -} and GFP{sup +} cytokeratin{sup +}. Thus marrow cells with the capacity to convert into cells with a lung phenotype after transplantation show a reversible increase with cytokine induced cell cycle transit. Previous studies have shown the phenotype of bone marrow stem cells fluctuates reversibly as these cells traverse cell cycle, leading to a continuum model of stem cell regulation. The present studies indicate that marrow stem cell production of nonhematopoietic cells also fluctuates on a continuum.« less

Treatment in carbon monoxide poisoning patients with headache: a prospective, multicenter, double-blind, controlled clinical trial.

PubMed

Ocak, Tarik; Tekin, Erdal; Basturk, Mustafa; Duran, Arif; Serinken, Mustafa; Emet, Mucahit

2016-11-01

There is a lack of specificity of the analgesic agents used to treat headache and underlying acute carbon monoxide poisoning. To compare effectiveness of "oxygen alone" vs "metoclopramide plus oxygen" vs "metamizole plus oxygen" therapy in treating carbon monoxide-induced headache. A prospective, multicenter, double-blind, controlled trial. Three emergency departments in Turkey. Adult carbon monoxide poisoning patients with headache. A total of 117 carbon monoxide-intoxicated patients with headache were randomized into 3 groups and assessed at baseline, 30 minutes, 90 minutes, and 4 hours. The primary outcome was patient-reported improvement rates for headache. Secondary end points included nausea, need for rescue medication during treatment, and reduction in carboxyhemoglobin levels. During observation, there was no statistical difference between drug type and visual analog scale score change at 30 minutes, 90 minutes, or 4 hours, for either headache or nausea. No rescue medication was needed during the study period. The reduction in carboxyhemoglobin levels did not differ among the 3 groups. The use of "oxygen alone" is as efficacious as "oxygen plus metoclopramide" or "oxygen plus metamizole sodium" in the treatment of carbon monoxide-induced headache. Copyright © 2016 Elsevier Inc. All rights reserved.

Genotoxic potential of bee venom (Apis Mellifera) on human peripheral blood lymphocytes in vitro using single cell gel electrophoresis assay.

PubMed

Gajski, Goran; Garaj-Vrhovac, Vera

2008-09-01

Bee venom (BV) has been known to have therapeutic applications in traditional medicine to treat variety of diseases. It is also known that bee venom possesses anti-inflammatory and anticancer effects and that it can inhibit proliferation and induces apoptosis in cancer cells, but there is lack of information regarding genotoxicity of whole bee venom on normal human cells. In the present study, peripheral blood human lymphocytes from healthy donor were exposed in vitro to different concentration (5, 10, 25, 50 and 100 micro g/mL) of whole bee venom at different time periods (1, 6 and 24 hours). The single cell gel electrophoresis (SCGE) assay was used to evaluate the genotoxicity towards human cells. Results showed statistically significant increase in DNA damage caused in BV treated human lymphocytes compared to corresponding control cells for the tail length and tail moment. These results show that the extent of DNA damage, determined by the use of single cell gel electrophoresis is time and dose dependent. Based on the results it is clear that whole bee venom induces DNA damage and has genotoxic potential on human peripheral blood lymphocytes in vitro.

Glioblastoma cells deficient in DNA-dependent protein kinase are resistant to cell death.

PubMed

Chen, George G; Sin, Fanny L F; Leung, Billy C S; Ng, Ho K; Poon, Wai S

2005-04-01

DNA-dependent protein kinase (DNA-PK), a nuclear serine/threonine kinase, is responsible for the DNA double-strand break repair. Cells lacking or with dysfunctional DNA-PK are often associated with mis-repair, chromosome aberrations, and complex exchanges, all of which are known to contribute to the development of human cancers including glioblastoma. Two human glioblastoma cell lines were used in the experiment, M059J cells lacking the catalytic subunit of DNA-PK, and their isogenic but DNA-PK proficient counterpart, M059K. We found that M059K cells were much more sensitive to staurosporine (STS) treatment than M059J cells, as demonstrated by MTT assay, TUNEL detection, and annexin-V and propidium iodide (PI) staining. A possible mechanism responsible for the different sensitivity in these two cell lines was explored by the examination of Bcl-2, Bax, Bak, and Fas. The cell death stimulus increased anti-apoptotic Bcl-2 and decreased pro-apoptotic Bcl-2 members (Bak and Bax) and Fas in glioblastoma cells deficient in DNA-PK. Activation of DNA-PK is known to promote cell death of human tumor cells via modulation of p53, which can down-regulate the anti-apoptotic Bcl-2 member proteins, induce pro-apoptotic Bcl-2 family members and promote a Bax-Bak interaction. Our experiment also demonstrated that the mode of glioblastoma cell death induced by STS consisted of both apoptosis and necrosis and the percentage of cell death in both modes was similar in glioblastoma cell lines either lacking DNA-PK or containing intact DNA-PK. Taken together, our findings suggest that DNA-PK has a positive role in the regulation of apoptosis in human glioblastomas. The aberrant expression of Bcl-2 family members and Fas was, at least in part, responsible for decreased sensitivity of DNA-PK deficient glioblastoma cells to cell death stimuli. 2004 Wiley-Liss, Inc.

Hepatitis B Virus Lacks Immune Activating Capacity, but Actively Inhibits Plasmacytoid Dendritic Cell Function

PubMed Central

Woltman, Andrea M.; Shi, Cui C.; Janssen, Harry L. A.

2011-01-01

Chronic hepatitis B virus (HBV) infection is caused by inadequate anti-viral immunity. Activation of plasmacytoid dendritic cells (pDC) leading to IFNα production is important for effective anti-viral immunity. Hepatitis B virus (HBV) infection lacks IFNα induction in animal models and patients and chronic HBV patients display impaired IFNα production by pDC. Therefore, HBV and HBV-derived proteins were examined for their effect on human pDC in vitro. In addition, the in vitro findings were compared to the function of pDC derived from chronic HBV patients ex vivo. In contrast to other viruses, HBV did not activate pDC. Moreover, HBV and HBsAg abrogated CpG-A/TLR9-induced, but not Loxoribine/TLR7-induced, mTOR-mediated S6 phosphorylation, subsequent IRF7 phosphorylation and IFNα gene transcription. HBV/HBsAg also diminished upregulation of co-stimulatory molecules, production of TNFα, IP-10 and IL-6 and pDC-induced NK cell function, whereas TLR7-induced pDC function was hardly affected. In line, HBsAg preferentially bound to TLR9-triggered pDC demonstrating that once pDC are able to bind HBV/HBsAg, the virus exerts its immune regulatory effect. HBV not only directly interfered with pDC function, but also indirectly by interfering with monocyte-pDC interaction. Also HBeAg diminished pDC function to a certain extent, but via another unknown mechanism. Interestingly, patients with HBeAg-positive chronic hepatitis B displayed impaired CpG-induced IFNα production by pDC without significant alterations in Loxoribine-induced pDC function compared to HBeAg-negative patients and healthy controls. The lack of activation and the active inhibition of pDC by HBV may both contribute to HBV persistence. The finding that the interaction between pDC and HBV may change upon activation may aid in the identification of a scavenging receptor supporting immunosuppressive effects of HBV and also in the design of novel treatment strategies for chronic HBV. PMID:21246041

Effects of Chronic Consumption of Sugar-Enriched Diets on Brain Metabolism and Insulin Sensitivity in Adult Yucatan Minipigs.

PubMed

Ochoa, Melissa; Malbert, Charles-Henri; Meurice, Paul; Val-Laillet, David

2016-01-01

Excessive sugar intake might increase the risk to develop eating disorders via an altered reward circuitry, but it remains unknown whether different sugar sources induce different neural effects and whether these effects are dependent from body weight. Therefore, we compared the effects of three high-fat and isocaloric diets varying only in their carbohydrate sources on brain activity of reward-related regions, and assessed whether brain activity is dependent on insulin sensitivity. Twenty-four minipigs underwent 18FDG PET brain imaging following 7-month intake of high-fat diets of which 20% in dry matter weight (36.3% of metabolisable energy) was provided by starch, glucose or fructose (n = 8 per diet). Animals were then subjected to a euglycemic hyperinsulinemic clamp to determine peripheral insulin sensitivity. After a 7-month diet treatment, all groups had substantial increases in body weight (from 36.02±0.85 to 63.33±0.81 kg; P<0.0001), regardless of the diet. All groups presented similar insulin sensitivity index (ISI = 1.39±0.10 mL·min-1·μUI·kg). Compared to starch, chronic exposure to fructose and glucose induced bilateral brain activations, i.e. increased basal cerebral glucose metabolism, in several reward-related brain regions including the anterior and dorsolateral prefrontal cortex, the orbitofrontal cortex, the anterior cingulate cortex, the caudate and putamen. The lack of differences in insulin sensitivity index and body weight suggests that the observed differences in basal brain glucose metabolism are not related to differences in peripheral insulin sensitivity and weight gain. The differences in basal brain metabolism in reward-related brain areas suggest the onset of cerebral functional alterations induced by chronic consumption of dietary sugars. Further studies should explore the underlying mechanisms, such as the availability of intestinal and brain sugar transporter, or the appearance of addictive-like behavioral correlates of these brain functional characteristics.

High pressure phase transformations revisited

NASA Astrophysics Data System (ADS)

Levitas, Valery I.

2018-04-01

High pressure phase transformations play an important role in the search for new materials and material synthesis, as well as in geophysics. However, they are poorly characterized, and phase transformation pressure and pressure hysteresis vary drastically in experiments of different researchers, with different pressure transmitting media, and with different material suppliers. Here we review the current state, challenges in studying phase transformations under high pressure, and the possible ways in overcoming the challenges. This field is critically compared with fields of phase transformations under normal pressure in steels and shape memory alloys, as well as plastic deformation of materials. The main reason for the above mentioned discrepancy is the lack of understanding that there is a fundamental difference between pressure-induced transformations under hydrostatic conditions, stress-induced transformations under nonhydrostatic conditions below yield, and strain-induced transformations during plastic flow. Each of these types of transformations has different mechanisms and requires a completely different thermodynamic and kinetic description and experimental characterization. In comparison with other fields the following challenges are indicated for high pressure phase transformation: (a) initial and evolving microstructure is not included in characterization of transformations; (b) continuum theory is poorly developed; (c) heterogeneous stress and strain fields in experiments are not determined, which leads to confusing material transformational properties with a system behavior. Some ways to advance the field of high pressure phase transformations are suggested. The key points are: (a) to take into account plastic deformations and microstructure evolution during transformations; (b) to formulate phase transformation criteria and kinetic equations in terms of stress and plastic strain tensors (instead of pressure alone); (c) to develop multiscale continuum theories, and (d) to couple experimental, theoretical, and computational studies of the behavior of a tested sample to extract information about fields of stress and strain tensors and concentration of high pressure phase, transformation criteria and kinetics. The ideal characterization should contain complete information which is required for simulation of the same experiments.

High pressure phase transformations revisited.

PubMed

Levitas, Valery I

2018-04-25

High pressure phase transformations play an important role in the search for new materials and material synthesis, as well as in geophysics. However, they are poorly characterized, and phase transformation pressure and pressure hysteresis vary drastically in experiments of different researchers, with different pressure transmitting media, and with different material suppliers. Here we review the current state, challenges in studying phase transformations under high pressure, and the possible ways in overcoming the challenges. This field is critically compared with fields of phase transformations under normal pressure in steels and shape memory alloys, as well as plastic deformation of materials. The main reason for the above mentioned discrepancy is the lack of understanding that there is a fundamental difference between pressure-induced transformations under hydrostatic conditions, stress-induced transformations under nonhydrostatic conditions below yield, and strain-induced transformations during plastic flow. Each of these types of transformations has different mechanisms and requires a completely different thermodynamic and kinetic description and experimental characterization. In comparison with other fields the following challenges are indicated for high pressure phase transformation: (a) initial and evolving microstructure is not included in characterization of transformations; (b) continuum theory is poorly developed; (c) heterogeneous stress and strain fields in experiments are not determined, which leads to confusing material transformational properties with a system behavior. Some ways to advance the field of high pressure phase transformations are suggested. The key points are: (a) to take into account plastic deformations and microstructure evolution during transformations; (b) to formulate phase transformation criteria and kinetic equations in terms of stress and plastic strain tensors (instead of pressure alone); (c) to develop multiscale continuum theories, and (d) to couple experimental, theoretical, and computational studies of the behavior of a tested sample to extract information about fields of stress and strain tensors and concentration of high pressure phase, transformation criteria and kinetics. The ideal characterization should contain complete information which is required for simulation of the same experiments.

Lack of Gender and Age Differences in Pain Measurements Following Exercise in People with Chronic Whiplash-Associated Disorders.

PubMed

Ickmans, Kelly; Malfliet, Anneleen; De Kooning, Margot; Goudman, Lisa; Hubloue, Ives; Schmitz, Tom; Goubert, Dorien; Aguilar-Ferrandiz, Maria Encarnacion

2017-09-01

Individuals with chronic whiplash associated disorders (WAD) present persistent pain in the absence of structural pathology. In these people, altered central pain processing and central sensitization are observed. The role of personal factors, such as gender and age, on pain processing mechanisms in chronic WAD, however, is still unclear. This study investigated possible gender- and age-related differences in self-reported and experimental pain measurements in people with chronic WAD. Besides the exercise-induced response on pain measurements between gender and age subgroups was recorded. Case-control study. University Hospital, Brussels. Self-reported pain and experimental pain measurements (pressure pain thresholds [PPT], occlusion cuff pressure, temporal summation, and conditioned pain modulation) were performed in 52 individuals (26 chronic WAD patients and 26 healthy controls), before and after a submaximal cycle exercise. Lower PPTs and occlusion cuff pressures were shown in chronic WAD in comparison with healthy controls. No gender and age differences regarding PPTs, occlusion cuff pressures and conditioned pain modulation were found in chronic WAD. Within the chronic WAD group, men showed higher self-reported pain compared to women and younger adults showed enhanced generalized pain facilitation compared to older adults. In addition, chronic WAD patients are able to inhibit exercise-induced hyperalgesia, but no gender and age differences in pain response following exercise were found. This study was sufficiently powered to detect differences between the chronic WAD and control group. However, a sufficient power was not reached when patients were divided in age and gender groups. Furthermore, only mechanical stimuli were included in the experimental pain measurements. Besides, psychosocial factors were not taken into account. Some alterations of altered pain processing are present in chronic WAD patients, however not in response to exercise. No gender and age differences in pain measurements were observed in people with chronic WAD.Key words: Neck pain, whiplash associated disorders, chronic pain, personal factors, age, gender, central sensitization, exercise induced hyperalgesia, pressure pain thresholds, self reported pain.

Protection of a Ceramide Synthase 2 Null Mouse from Drug-induced Liver Injury

PubMed Central

Park, Woo-Jae; Park, Joo-Won; Erez-Roman, Racheli; Kogot-Levin, Aviram; Bame, Jessica R.; Tirosh, Boaz; Saada, Ann; Merrill, Alfred H.; Pewzner-Jung, Yael; Futerman, Anthony H.

2013-01-01

Very long chain (C22-C24) ceramides are synthesized by ceramide synthase 2 (CerS2). A CerS2 null mouse displays hepatopathy because of depletion of C22-C24 ceramides, elevation of C16-ceramide, and/or elevation of sphinganine. Unexpectedly, CerS2 null mice were resistant to acetaminophen-induced hepatotoxicity. Although there were a number of biochemical changes in the liver, such as increased levels of glutathione and multiple drug-resistant protein 4, these effects are unlikely to account for the lack of acetaminophen toxicity. A number of other hepatotoxic agents, such as d-galactosamine, CCl4, and thioacetamide, were also ineffective in inducing liver damage. All of these drugs and chemicals require connexin (Cx) 32, a key gap junction protein, to induce hepatotoxicity. Cx32 was mislocalized to an intracellular location in hepatocytes from CerS2 null mice, which resulted in accelerated rates of its lysosomal degradation. This mislocalization resulted from the altered membrane properties of the CerS2 null mice, which was exemplified by the disruption of detergent-resistant membranes. The lack of acetaminophen toxicity and Cx32 mislocalization were reversed upon infection with recombinant adeno-associated virus expressing CerS2. We establish that Gap junction function is compromised upon altering the sphingolipid acyl chain length composition, which is of relevance for understanding the regulation of drug-induced liver injury. PMID:24019516

Prophylaxis and management of acute radiation-induced skin toxicity: a survey of practice across Europe and the USA.

PubMed

O'Donovan, A; Coleman, M; Harris, R; Herst, P

2015-05-01

Radiation-induced toxicity is a common adverse side effect of radiation therapy. Previous studies have demonstrated a lack of evidence to support common skincare advice for radiotherapy patients. The aim of the current study was to investigate the management of radiation-induced skin toxicity across Europe and the USA. Where previous surveys have focused on national practice or treatment of specific sites, the current study aimed to gain a broader representation of skincare practice. An anonymous online survey investigating various aspects of radiotherapy skincare management was distributed to departments across Europe and the USA (n = 181/737 responded i.e. 25%). The UK was excluded as a similar survey was carried out in 2011. The results highlight the lack of consistency in both the prevention and management of radiation-induced skin toxicity. Recommended products are often not based on evidence-based practice. Examples include the continued use of aqueous cream and gentian violet, as well as the recommendations on washing restrictions during treatment. To our knowledge, this is the most extensive survey to date on the current management of radiation-induced skin toxicity. This study highlights significant disparities between clinical practice and research-based evidence published in recent systematic reviews and guidelines. Ongoing large prospective randomised trials are urgently needed. © 2014 John Wiley & Sons Ltd.

Supplementation of Low- and High-fat Diets with Fermentable Fiber Exacerbates Severity of DSS-induced Acute Colitis.

PubMed

Miles, Jennifer P; Zou, Jun; Kumar, Matam-Vijay; Pellizzon, Michael; Ulman, Edward; Ricci, Matthew; Gewirtz, Andrew T; Chassaing, Benoit

2017-07-01

Lack of dietary fiber has been suggested to increase the risk of developing various chronic inflammatory diseases, whereas supplementation of diets with fiber might offer an array of health-promoting benefits. Consistent with this theme, we recently reported that in mice, compositionally defined diets that are made with purified ingredients and lack fermentable fiber promote low-grade inflammation and metabolic syndrome, both of which could be ameliorated by supplementation of such diets with the fermentable fiber inulin. Herein, we examined if, relative to a grain-based mouse diet (chow), compositionally defined diet consumption would impact development of intestinal inflammation induced by dextran sulfate sodium (DSS) and moreover, whether DSS-induced colitis might also be attenuated by diets supplemented with inulin. Analogous to their promotion of low-grade inflammation, compositionally defined diet of high- and low-fat content with cellulose increased the severity of DSS-induced colitis relative to chow. However, in contrast to the case of low-grade inflammation, addition of inulin, but not the insoluble fiber cellulose, further exacerbated the severity of colitis and its associated clinical manifestations (weight loss and bleeding) in both low- and high-fat diets. While inulin, and perhaps other fermentable fibers, can ameliorate low-grade inflammation and associated metabolic disease, it also has the potential to exacerbate disease severity in response to inducers of acute colitis.

Histone deacetylase inhibitor treatment induces ‘BRCAness’ and synergistic lethality with PARP inhibitor and cisplatin against human triple negative breast cancer cells

PubMed Central

Ha, Kyungsoo; Bhaskara, Srividya; Cerchietti, Leandro; Devaraj, Santhana G. T.; Shah, Bhavin; Sharma, Sunil; Chang, Jenny C.; Melnick, Ari M.; Hiebert, Scott; Bhalla, Kapil N.

2014-01-01

There is an unmet need to develop new, more effective and safe therapies for the aggressive forms of triple negative breast cancers (TNBCs). While up to 20% of women under 50 years of age with TNBC harbor germline mutations in BRCA1, and these tumors are sensitive to treatment with poly(ADP) ribose polymerase inhibitors, a majority of TNBCs lack BRCA1 mutations or loss of expression. Findings presented here demonstrate that by attenuating the levels of DNA damage response and homologous recombination proteins, pan-histone deacetylase inhibitor (HDI) treatment induces ‘BRCAness’ and sensitizes TNBC cells lacking BRCA1 to lethal effects of PARP inhibitor or cisplatin. Treatment with HDI also induced hyperacetylation of nuclear hsp90. Similar effects were observed following shRNA-mediated depletion of HDAC3, confirming its role as the deacetylase for nuclear HSP90. Furthermore, cotreatment with HDI and ABT-888 induced significantly more DNA strand breaks than either agent alone, and synergistically induced apoptosis of TNBC cells. Notably, co-treatment with HDI and ABT-888 significantly reduced in vivo tumor growth and markedly improved the survival of mice bearing TNBC cell xenografts. These findings support the rationale to interrogate the clinical activity of this novel combination against human TNBC, irrespective of its expression of mutant BRCA1. PMID:25026298

Light-Mediated Kinetic Control Reveals the Temporal Effect of the Raf/MEK/ERK Pathway in PC12 Cell Neurite Outgrowth

PubMed Central

Zhang, Kai; Duan, Liting; Ong, Qunxiang; Lin, Ziliang; Varman, Pooja Mahendra; Sung, Kijung; Cui, Bianxiao

2014-01-01

It has been proposed that differential activation kinetics allows cells to use a common set of signaling pathways to specify distinct cellular outcomes. For example, nerve growth factor (NGF) and epidermal growth factor (EGF) induce different activation kinetics of the Raf/MEK/ERK signaling pathway and result in differentiation and proliferation, respectively. However, a direct and quantitative linkage between the temporal profile of Raf/MEK/ERK activation and the cellular outputs has not been established due to a lack of means to precisely perturb its signaling kinetics. Here, we construct a light-gated protein-protein interaction system to regulate the activation pattern of the Raf/MEK/ERK signaling pathway. Light-induced activation of the Raf/MEK/ERK cascade leads to significant neurite outgrowth in rat PC12 pheochromocytoma cell lines in the absence of growth factors. Compared with NGF stimulation, light stimulation induces longer but fewer neurites. Intermittent on/off illumination reveals that cells achieve maximum neurite outgrowth if the off-time duration per cycle is shorter than 45 min. Overall, light-mediated kinetic control enables precise dissection of the temporal dimension within the intracellular signal transduction network. PMID:24667437

Ultrafast energy- and momentum-resolved dynamics of magnetic correlations in the photo-doped Mott insulator Sr2IrO4.

PubMed

Dean, M P M; Cao, Y; Liu, X; Wall, S; Zhu, D; Mankowsky, R; Thampy, V; Chen, X M; Vale, J G; Casa, D; Kim, Jungho; Said, A H; Juhas, P; Alonso-Mori, R; Glownia, J M; Robert, A; Robinson, J; Sikorski, M; Song, S; Kozina, M; Lemke, H; Patthey, L; Owada, S; Katayama, T; Yabashi, M; Tanaka, Yoshikazu; Togashi, T; Liu, J; Rayan Serrao, C; Kim, B J; Huber, L; Chang, C-L; McMorrow, D F; Först, M; Hill, J P

2016-06-01

Measuring how the magnetic correlations evolve in doped Mott insulators has greatly improved our understanding of the pseudogap, non-Fermi liquids and high-temperature superconductivity. Recently, photo-excitation has been used to induce similarly exotic states transiently. However, the lack of available probes of magnetic correlations in the time domain hinders our understanding of these photo-induced states and how they could be controlled. Here, we implement magnetic resonant inelastic X-ray scattering at a free-electron laser to directly determine the magnetic dynamics after photo-doping the Mott insulator Sr2IrO4. We find that the non-equilibrium state, 2 ps after the excitation, exhibits strongly suppressed long-range magnetic order, but hosts photo-carriers that induce strong, non-thermal magnetic correlations. These two-dimensional (2D) in-plane Néel correlations recover within a few picoseconds, whereas the three-dimensional (3D) long-range magnetic order restores on a fluence-dependent timescale of a few hundred picoseconds. The marked difference in these two timescales implies that the dimensionality of magnetic correlations is vital for our understanding of ultrafast magnetic dynamics.

Immunoglobulin GM and KM genes and measles vaccine-induced humoral immunity.

PubMed

Ovsyannikova, Inna G; Larrabee, Beth R; Schaid, Daniel J; Poland, Gregory A

2017-10-04

Identifying genetic polymorphisms that explain variations in humoral immunity to live measles virus vaccine is of great interest. Immunoglobulin GM (heavy chain) and KM (light chain) allotypes are genetic markers known to be associated with susceptibility to several infectious diseases. We assessed associations between GM and KM genotypes and measles vaccine humoral immunity (neutralizing antibody titers) in a combined cohort (n=1796) of racially diverse healthy individuals (age 18-41years). We did not discover any significant associations between GM and/or KM genotypes and measles vaccine-induced neutralizing antibody titers. African-American subjects had higher neutralizing antibody titers than Caucasians (1260mIU/mL vs. 740mIU/mL, p=7.10×10 -13 ), and those titers remained statistically significant (p=1.68×10 -09 ) after adjusting for age at enrollment and time since last vaccination. There were no statistically significant sex-specific differences in measles-induced neutralizing antibody titers in our study (p=0.375). Our data indicate a surprising lack of evidence for an association between GM and KM genotypes and measles-specific neutralizing antibody titers, despite the importance of these immune response genes. Copyright © 2017 Elsevier Ltd. All rights reserved.

Activation of NOX2 by the stimulation of ionotropic and metabotropic glutamate receptors contributes to glutamate neurotoxicity in vivo through the production of reactive oxygen species and calpain activation.

PubMed

Guemez-Gamboa, Alicia; Estrada-Sánchez, Ana María; Montiel, Teresa; Páramo, Blanca; Massieu, Lourdes; Morán, Julio

2011-11-01

Prolonged activation of glutamate receptors leads to excitotoxicity. Several processes such as reactive oxygen species (ROS) production and activation of the calcium-dependent protease, calpain, contribute to glutamate-induced damage. It has been suggested that the ROS-producing enzyme, NADPH oxidase (NOX), plays a role in excitotoxicity. Studies have reported NOX activation after NMDA receptor stimulation during excitotoxic damage, but the role of non-NMDA and metabotropic receptors is unknown. We evaluated the roles of different glutamate receptor subtypes on NOX activation and neuronal death induced by the intrastriatal administration of glutamate in mice. In wild-type mice, NOX2 immunoreactivity in neurons and microglia was stimulated by glutamate administration, and it progressively increased as microglia became activated; calpain activity was also induced. By contrast, mice lacking NOX2 were less vulnerable to excitotoxicity, and there was reduced ROS production and protein nitrosylation, microglial reactivity, and calpain activation. These results suggest that NOX2 is stimulated by glutamate in neurons and reactive microglia through the activation of ionotropic and metabotropic receptors. Neuronal damage involves ROS production by NOX2, which, in turn, contributes to calpain activation.

Evolution of plant growth and defense in a continental introduction.

PubMed

Agrawal, Anurag A; Hastings, Amy P; Bradburd, Gideon S; Woods, Ellen C; Züst, Tobias; Harvey, Jeffrey A; Bukovinszky, Tibor

2015-07-01

Substantial research has addressed adaptation of nonnative biota to novel environments, yet surprisingly little work has integrated population genetic structure and the mechanisms underlying phenotypic differentiation in ecologically important traits. We report on studies of the common milkweed Asclepias syriaca, which was introduced from North America to Europe over the past 400 years and which lacks most of its specialized herbivores in the introduced range. Using 10 populations from each continent grown in a common environment, we identified several growth and defense traits that have diverged, despite low neutral genetic differentiation between continents. We next developed a Bayesian modeling approach to account for relationships between molecular and phenotypic differences, confirming that continental trait differentiation was greater than expected from neutral genetic differentiation. We found evidence that growth-related traits adaptively diverged within and between continents. Inducible defenses triggered by monarch butterfly herbivory were substantially reduced in European populations, and this reduction in inducibility was concordant with altered phytohormonal dynamics, reduced plant growth, and a trade-off with constitutive investment. Freedom from the community of native and specialized herbivores may have favored constitutive over induced defense. Our replicated analysis of plant growth and defense, including phenotypically plastic traits, suggests adaptive evolution following a continental introduction.

Specific TRPC6 Channel Activation, a Novel Approach to Stimulate Keratinocyte Differentiation*S⃞

PubMed Central

Müller, Margarethe; Essin, Kirill; Hill, Kerstin; Beschmann, Heike; Rubant, Simone; Schempp, Christoph M.; Gollasch, Maik; Boehncke, W. Henning; Harteneck, Christian; Müller, Walter E.; Leuner, Kristina

2008-01-01

The protective epithelial barrier in our skin undergoes constant regulation, whereby the balance between differentiation and proliferation of keratinocytes plays a major role. Impaired keratinocyte differentiation and proliferation are key elements in the pathophysiology of several important dermatological diseases, including atopic dermatitis and psoriasis. Ca2+ influx plays an essential role in this process presumably mediated by different transient receptor potential (TRP) channels. However, investigating their individual role was hampered by the lack of specific stimulators or inhibitors. Because we have recently identified hyperforin as a specific TRPC6 activator, we investigated the contribution of TRPC6 to keratinocyte differentiation and proliferation. Like the endogenous differentiation stimulus high extracellular Ca2+ concentration ([Ca2+]o), hyperforin triggers differentiation in HaCaT cells and in primary cultures of human keratinocytes by inducing Ca2+ influx via TRPC6 channels and additional inhibition of proliferation. Knocking down TRPC6 channels prevents the induction of Ca2+- and hyperforin-induced differentiation. Importantly, TRPC6 activation is sufficient to induce keratinocyte differentiation similar to the physiological stimulus [Ca2+]o. Therefore, TRPC6 activation by hyperforin may represent a new innovative therapeutic strategy in skin disorders characterized by altered keratinocyte differentiation. PMID:18818211

A low K+ signal is required for functional high-affinity K+ uptake through HAK5 transporters.

PubMed

Rubio, Francisco; Fon, Mario; Ródenas, Reyes; Nieves-Cordones, Manuel; Alemán, Fernando; Rivero, Rosa M; Martínez, Vicente

2014-11-01

The high-affinity K(+) transporter HAK5 is a key system for root K(+) uptake and, under very low external K(+), the only one capable of supplying K(+) to the plant. Functional HAK5-mediated K(+) uptake should be tightly regulated for plant adaptation to different environmental conditions. Thus, it has been described that the gene encoding the transporter is transcriptionally regulated, being highly induced under K(+) limitation. Here we show that environmental conditions, such as the lack of K(+), NO(3)(-) or P, that induced a hyperpolarization of the plasma membrane of root cells, induce HAK5 transcription. However, only the deprivation of K(+) produces functional HAK5-mediated K(+) uptake in the root. These results suggest on the one hand the existence of a posttranscriptional regulation of HAK5 elicited by the low K(+) signal and on the other that HAK5 may be involved in yet-unknown functions related to NO(3)(-) and P deficiencies. These results have been obtained here with Solanum lycopersicum (cv. Micro-Tom) as well as Arabidopsis thaliana plants, suggesting that the posttranscriptional regulation of high-affinity HAK transporters take place in all plant species. © 2014 Scandinavian Plant Physiology Society.

Calcium-dependent nonspecific permeability of the inner mitochondrial membrane is not induced in mitochondria of the yeast Endomyces magnusii.

PubMed

Deryabina, Y I; Isakova, E P; Shurubor, E I; Zvyagilskaya, R A

2004-09-01

Mitochondria of the yeast Endomyces magnusii were examined for the presence of a Ca2+- and phosphate-induced permeability of the inner mitochondrial membrane (pore). For this purpose, coupled mitochondria were incubated under conditions known to induce the permeability transition pore in animal mitochondria, i.e., in the presence of high concentrations of Ca2+ and P(i), prooxidants (t-butylhydroperoxide), oxaloacetate, atractyloside (an inhibitor of ADP/ATP translocator), SH-reagents, by depletion of adenine nucleotide pools, and deenergization of the mitochondria. Large amplitude swelling, collapse of the membrane potential, and efflux of the accumulated Ca2+ were used as parameters for demonstrating pore induction. E. magnusii mitochondria were highly resistant to the above-mentioned substances. Deenergization of mitochondria or depletion of adenine nucleotide pools have no effect on low-amplitude swelling or the other parameters. Cyclosporin A, a specific inhibitor of the nonspecific permeability transition in animal mitochondria, did not affect the parameters measured. It is thus evident that E. magnusii mitochondria lack a functional Ca2+-dependent pore, or possess a pore differently regulated as compared to that of mammalian mitochondria.

Progress and Challenges toward the Development of Vaccines against Avian Infectious Bronchitis

PubMed Central

Bande, Faruku; Arshad, Siti Suri; Hair Bejo, Mohd; Moeini, Hassan; Omar, Abdul Rahman

2015-01-01

Avian infectious bronchitis (IB) is a widely distributed poultry disease that has huge economic impact on poultry industry. The continuous emergence of new IBV genotypes and lack of cross protection among different IBV genotypes have been an important challenge. Although live attenuated IB vaccines remarkably induce potent immune response, the potential risk of reversion to virulence, neutralization by the maternal antibodies, and recombination and mutation events are important concern on their usage. On the other hand, inactivated vaccines induce a weaker immune response and may require multiple dosing and/or the use of adjuvants that probably have potential safety risks and increased economic burdens. Consequently, alternative IB vaccines are widely sought. Recent advances in recombinant DNA technology have resulted in experimental IB vaccines that show promise in antibody and T-cells responses, comparable to live attenuated vaccines. Recombinant DNA vaccines have also been enhanced to target multiple serotypes and their efficacy has been improved using delivery vectors, nanoadjuvants, and in ovo vaccination approaches. Although most recombinant IB DNA vaccines are yet to be licensed, it is expected that these types of vaccines may hold sway as future vaccines for inducing a cross protection against multiple IBV serotypes. PMID:25954763

Wave energy and swimming performance shape coral reef fish assemblages

PubMed Central

Fulton, C.J; Bellwood, D.R; Wainwright, P.C

2005-01-01

Physical factors often have an overriding influence on the distribution patterns of organisms, and can ultimately shape the long-term structure of communities. Although distribution patterns in sessile marine organisms have frequently been attributed to functional characteristics interacting with wave-induced water motion, similar evidence for mobile organisms is lacking. Links between fin morphology and swimming performance were examined in three diverse coral reef fish families from two major evolutionary lineages. Among-habitat variation in morphology and performance was directly compared with quantitative values of wave-induced water motion from seven coral reef habitats of different depth and wave exposure on the Great Barrier Reef. Fin morphology was strongly correlated with both field and experimental swimming speeds in all three families. The range of observed swimming speeds coincided closely with the magnitude of water velocities commonly found on coral reefs. Distribution patterns in all three families displayed highly congruent relationships between fin morphology and wave-induced water motion. Our findings indicate a general functional relationship between fin morphology and swimming performance in labriform-swimming fishes, and provide quantitative evidence that wave energy may directly influence the assemblage structure of coral reef fishes through interactions with morphology and swimming performance. PMID:15888415

Comparative phenotypic and functional analysis of migratory dendritic cell subsets from human oral mucosa and skin

PubMed Central

van de Ven, Rieneke; Thon, Maria; Gibbs, Susan; de Gruijl, Tanja D.

2017-01-01

Antigen exposure to oral mucosa is generally thought to lead to immune tolerance induction. However, very little is known about the subset composition and function of dendritic cells (DC) migrating from human oral mucosa. Here we show that migratory DC from healthy human gingival explants consist of the same phenotypic subsets in the same frequency distribution as DC migrating from human skin. The gingival CD1a+ Langerhans cell and interstitial DC subsets lacked CXCR4 expression in contrast to their cutaneous counterparts, pointing to different migration mechanisms, consistent with previous observations in constructed skin and gingival equivalents. Remarkably, without any exogenous conditioning, gingival explants released higher levels of inflammatory cytokines than human skin explants, resulting in higher DC migration rates and a superior ability of migrated DC to prime allogeneic T cells and to induce type-1 effector T cell differentiation. From these observations we conclude that rather than an intrinsic ability to induce T cell tolerance, DC migrating from oral mucosa may have a propensity to induce effector T cell immunity and maintain a high state of alert against possible pathogenic intruders in the steady state. These findings may have implications for oral immunization strategies. PMID:28704477

The effect of the anabolic steroid, nandrolone, in conditioned place preference and D1 dopamine receptor expression in adolescent and adult mice.

PubMed

Martínez-Rivera, Freddyson J; Natal-Albelo, Eduardo J; Martínez, Namyr A; Orozco-Vega, Roberto A; Muñiz-Seda, Oscar A; Barreto-Estrada, Jennifer L

2015-04-01

Adolescents and adults engage in anabolic-androgenic steroid (AAS) misuse seeking their anabolic effects, even though later on, many could develop neuropsychological dependence. Previously, we have shown that nandrolone induces conditioned place preference (CPP) in adult male mice. However, whether nandrolone induces CPP during adolescence remains unknown. In this study, the CPP test was used to determine the rewarding properties of nandrolone (7.5 mg/kg) in adolescent mice. In addition, since D1 dopamine receptors (D1DR) are critical for reward-related processes, the effect of nandrolone on the expression of D1DR in the nucleus accumbens (NAc) was investigated by Western blot analysis. Similar to our previous results, nandrolone induced CPP in adults. However, in adolescents, nandrolone failed to produce place preference. At the molecular level, nandrolone decreased D1DR expression in the NAc only in adult mice. Our data suggest that nandrolone may not be rewarding in adolescents at least during short-term use. The lack of nandrolone rewarding effects in adolescents may be due, in part to differences in D1DR expression during development. Copyright © 2015 Elsevier B.V. All rights reserved.

The effect of the anabolic steroid, nandrolone, in conditioned place preference and D1 dopamine receptor expression in adolescent and adult mice

PubMed Central

Martínez-Rivera, Freddyson J.; Natal-Albelo, Eduardo J.; Martínez, Namyr A.; Orozco-Vega, Roberto A.; Muñiz-Seda, Oscar A.; Barreto-Estrada, Jennifer L.

2015-01-01

Adolescents and adults engage in anabolic-androgenic steroid (AAS) misuse seeking their anabolic effects, even though later on, many could develop neuropsychological dependence. Previously, we have shown that nandrolone induces conditioned place preference (CPP) in adult male mice. However, whether nandrolone induces CPP during adolescence remains unknown. In this study, the CPP test was used to determine the rewarding properties of nandrolone (7.5 mg/kg) in adolescent mice. In addition, since D1 dopamine receptors (D1DR) are critical for reward-related processes, the effect of nandrolone on the expression of D1DR in the nucleus accumbens (NAc) was investigated by Western blot analysis. Similar to our previous results, nandrolone induced CPP in adults. However, in adolescents, nandrolone failed to produce place preference. At the molecular level, nandrolone decreased D1DR expression in the NAc only in adult mice. Our data suggest that nandrolone may not be rewarding in adolescents at least during short-term use. The lack of nandrolone rewarding effects in adolescents may be due, in part to differences in D1DR expression during development. PMID:25612844

Gut microbiota in experimental murine model of Graves' orbitopathy established in different environments may modulate clinical presentation of disease.

PubMed

Masetti, Giulia; Moshkelgosha, Sajad; Köhling, Hedda-Luise; Covelli, Danila; Banga, Jasvinder Paul; Berchner-Pfannschmidt, Utta; Horstmann, Mareike; Diaz-Cano, Salvador; Goertz, Gina-Eva; Plummer, Sue; Eckstein, Anja; Ludgate, Marian; Biscarini, Filippo; Marchesi, Julian Roberto

2018-05-25

Variation in induced models of autoimmunity has been attributed to the housing environment and its effect on the gut microbiota. In Graves' disease (GD), autoantibodies to the thyrotropin receptor (TSHR) cause autoimmune hyperthyroidism. Many GD patients develop Graves' orbitopathy or ophthalmopathy (GO) characterized by orbital tissue remodeling including adipogenesis. Murine models of GD/GO would help delineate pathogenetic mechanisms, and although several have been reported, most lack reproducibility. A model comprising immunization of female BALBc mice with a TSHR expression plasmid using in vivo electroporation was reproduced in two independent laboratories. Similar orbital disease was induced in both centers, but differences were apparent (e.g., hyperthyroidism in Center 1 but not Center 2). We hypothesized a role for the gut microbiota influencing the outcome and reproducibility of induced GO. We combined metataxonomics (16S rRNA gene sequencing) and traditional microbial culture of the intestinal contents from the GO murine model, to analyze the gut microbiota in the two centers. We observed significant differences in alpha and beta diversity and in the taxonomic profiles, e.g., operational taxonomic units (OTUs) from the genus Lactobacillus were more abundant in Center 2, and Bacteroides and Bifidobacterium counts were more abundant in Center 1 where we also observed a negative correlation between the OTUs of the genus Intestinimonas and TSHR autoantibodies. Traditional microbiology largely confirmed the metataxonomics data and indicated significantly higher yeast counts in Center 1 TSHR-immunized mice. We also compared the gut microbiota between immunization groups within Center 2, comprising the TSHR- or βgal control-immunized mice and naïve untreated mice. We observed a shift of the TSHR-immunized mice bacterial communities described by the beta diversity weighted Unifrac. Furthermore, we observed a significant positive correlation between the presence of Firmicutes and orbital-adipogenesis specifically in TSHR-immunized mice. The significant differences observed in microbiota composition from BALBc mice undergoing the same immunization protocol in comparable specific-pathogen-free (SPF) units in different centers support a role for the gut microbiota in modulating the induced response. The gut microbiota might also contribute to the heterogeneity of induced response since we report potential disease-associated microbial taxonomies and correlation with ocular disease.

Exploring the Complex Pattern of Information Spreading in Online Blog Communities

PubMed Central

Pei, Sen; Muchnik, Lev; Tang, Shaoting; Zheng, Zhiming; Makse, Hernán A.

2015-01-01

Information spreading in online social communities has attracted tremendous attention due to its utmost practical values in applications. Despite that several individual-level diffusion data have been investigated, we still lack the detailed understanding of the spreading pattern of information. Here, by comparing information flows and social links in a blog community, we find that the diffusion processes are induced by three different spreading mechanisms: social spreading, self-promotion and broadcast. Although numerous previous studies have employed epidemic spreading models to simulate information diffusion, we observe that such models fail to reproduce the realistic diffusion pattern. In respect to users behaviors, strikingly, we find that most users would stick to one specific diffusion mechanism. Moreover, our observations indicate that the social spreading is not only crucial for the structure of diffusion trees, but also capable of inducing more subsequent individuals to acquire the information. Our findings suggest new directions for modeling of information diffusion in social systems, and could inform design of efficient propagation strategies based on users behaviors. PMID:25985081

Molecular Basis of Asbestos-Induced Lung Disease

PubMed Central

Liu, Gang; Cheresh, Paul; Kamp, David W.

2013-01-01

Asbestos causes asbestosis and malignancies by molecular mechanisms that are not fully understood. The modes of action underlying asbestosis, lung cancer, and mesothelioma appear to differ depending on the fiber type, lung clearance, and genetics. After reviewing the key pathologic changes following asbestos exposure, we examine recently identified pathogenic pathways, with a focus on oxidative stress. Alveolar epithelial cell apoptosis, which is an important early event in asbestosis, is mediated by mitochondria- and p53-regulated death pathways and may be modulated by the endoplasmic reticulum. We review mitochondrial DNA (mtDNA)-damage and -repair mechanisms, focusing on 8-oxoguanine DNA glycosylase, as well as cross talk between reactive oxygen species production, mtDNA damage, p53, OGG1, and mitochondrial aconitase. These new insights into the molecular basis of asbestos-induced lung diseases may foster the development of novel therapeutic targets for managing degenerative diseases (e.g., asbestosis and idiopathic pulmonary fibrosis), tumors, and aging, for which effective management is lacking. PMID:23347351

Exploring the complex pattern of information spreading in online blog communities.

PubMed

Pei, Sen; Muchnik, Lev; Tang, Shaoting; Zheng, Zhiming; Makse, Hernán A

2015-01-01

Information spreading in online social communities has attracted tremendous attention due to its utmost practical values in applications. Despite that several individual-level diffusion data have been investigated, we still lack the detailed understanding of the spreading pattern of information. Here, by comparing information flows and social links in a blog community, we find that the diffusion processes are induced by three different spreading mechanisms: social spreading, self-promotion and broadcast. Although numerous previous studies have employed epidemic spreading models to simulate information diffusion, we observe that such models fail to reproduce the realistic diffusion pattern. In respect to users behaviors, strikingly, we find that most users would stick to one specific diffusion mechanism. Moreover, our observations indicate that the social spreading is not only crucial for the structure of diffusion trees, but also capable of inducing more subsequent individuals to acquire the information. Our findings suggest new directions for modeling of information diffusion in social systems, and could inform design of efficient propagation strategies based on users behaviors.

[Coronary artery disease--relevance of total coronary revascularization on the incidence of malignant arrhythmias].

PubMed

Brandt, A; Gulba, D C

2006-12-01

Myocardial ischemia induces redistribution of different ions (H(+), K(+), Na(+), Ca(++)) across the cardiomyocyte membrane, as well as the loss of intracellular ATP content. This results in changes in the electrical properties including shortening of the action potential, appearance of delayed afterpotentials, and a modified refractoriness of the cardiomyocyte. These changes may induce or support malignant cardiac arrhythmias. Supersensitivity of sympathetic denervated myocardium may further support the electrical instability of ischemic myocardium.Virtues of studies indicate that patients with coronary artery disease who develop complex arrhythmias during or after exercise bear a substantially increased risk for sudden cardiac death. Other studies report about arrhythmic stabilization and reduced mortality if patients with reversible myocardial ischemia receive complete revascularization. However, none of these studies is without methodological flaws. Due to the lack of methodologically sound studies in sufficiently large patient cohorts, the question whether complete coronary revascularisation improves the prognosis of patients with coronary artery disease and which strategy (medical, interventional, or surgical) warrants the best outcomes remains open.

Apoptosis-Inducing-Factor-Dependent Mitochondrial Function Is Required for T Cell but Not B Cell Function.

PubMed

Milasta, Sandra; Dillon, Christopher P; Sturm, Oliver E; Verbist, Katherine C; Brewer, Taylor L; Quarato, Giovanni; Brown, Scott A; Frase, Sharon; Janke, Laura J; Perry, S Scott; Thomas, Paul G; Green, Douglas R

2016-01-19

The role of apoptosis inducing factor (AIF) in promoting cell death versus survival remains controversial. We report that the loss of AIF in fibroblasts led to mitochondrial electron transport chain defects and loss of proliferation that could be restored by ectopic expression of the yeast NADH dehydrogenase Ndi1. Aif-deficiency in T cells led to decreased peripheral T cell numbers and defective homeostatic proliferation, but thymic T cell development was unaffected. In contrast, Aif-deficient B cells developed and functioned normally. The difference in the dependency of T cells versus B cells on AIF for function and survival correlated with their metabolic requirements. Ectopic Ndi1 expression rescued homeostatic proliferation of Aif-deficient T cells. Despite its reported roles in cell death, fibroblasts, thymocytes and B cells lacking AIF underwent normal death. These studies suggest that the primary role of AIF relates to complex I function, with differential effects on T and B cells. Copyright © 2016 Elsevier Inc. All rights reserved.

Short term changes in the proteome of human cerebral organoids induced by 5-MeO-DMT.

PubMed

Dakic, Vanja; Minardi Nascimento, Juliana; Costa Sartore, Rafaela; Maciel, Renata de Moraes; de Araujo, Draulio B; Ribeiro, Sidarta; Martins-de-Souza, Daniel; Rehen, Stevens K

2017-10-09

Dimethyltryptamines are entheogenic serotonin-like molecules present in traditional Amerindian medicine recently associated with cognitive gains, antidepressant effects, and changes in brain areas related to attention. Legal restrictions and the lack of adequate experimental models have limited the understanding of how such substances impact human brain metabolism. Here we used shotgun mass spectrometry to explore proteomic differences induced by 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) on human cerebral organoids. Out of the 6,728 identified proteins, 934 were found differentially expressed in 5-MeO-DMT-treated cerebral organoids. In silico analysis reinforced previously reported anti-inflammatory actions of 5-MeO-DMT and revealed modulatory effects on proteins associated with long-term potentiation, the formation of dendritic spines, including those involved in cellular protrusion formation, microtubule dynamics, and cytoskeletal reorganization. Our data offer the first insight about molecular alterations caused by 5-MeO-DMT in human cerebral organoids.

Lack of Evidence That Neural Empathic Responses Are Blunted in Excessive Users of Violent Video Games: An fMRI Study

PubMed Central

Szycik, Gregor R.; Mohammadi, Bahram; Münte, Thomas F.; te Wildt, Bert T.

2017-01-01

The use of violent video games has been often linked to increase of aggressive behavior. According to the General Aggression Model, one of the central mechanisms for this aggressiveness inducing impact is an emotional desensitization process resulting from long lasting repeated violent game playing. This desensitization should evidence itself in a lack of empathy. Recent research has focused primarily on acute, short term impact of violent media use but only little is known about long term effects. In this study 15 excessive users of violent games and control subjects matched for age and education viewed pictures depicting emotional and neutral situations with and without social interaction while fMRI activations were obtained. While the typical pattern of activations for empathy and theory of mind networks was seen, both groups showed no differences in brain responses. We interpret our results as evidence against the desensitization hypothesis and suggest that the impact of violent media on emotional processing may be rather acute and short-lived. PMID:28337156

Is refeeding syndrome relevant for critically ill patients?

PubMed

Koekkoek, Wilhelmina A C; Van Zanten, Arthur R H

2018-03-01

To summarize recent relevant studies regarding refeeding syndrome (RFS) in critically ill patients and provide recommendations for clinical practice. Recent knowledge regarding epidemiology of refeeding syndrome among critically ill patients, how to identify ICU patients at risk, and strategies to reduce the potential negative impact on outcome are discussed. RFS is a potentially fatal acute metabolic derangement that ultimately can result in marked morbidity and even mortality. These metabolic derangements in ICU patients differ from otherwise healthy patients with RFS, as there is lack of anabolism. This is because of external stressors inducing a hypercatabolic response among other reasons also reflected by persistent high glucagon despite initiation of feeding. Lack of a proper uniform definition complicates diagnosis and research of RFS. However, refeeding hypophosphatemia is commonly encountered during critical illness. The correlations between risk factors proposed by international guidelines and the occurrence of RFS in ICU patients remains unclear. Therefore, regular phosphate monitoring is recommended. Based on recent trials among critically ill patients, only treatment with supplementation of electrolytes and vitamins seems not sufficient. In addition, caloric restriction for several days and gradual increase of caloric intake over days is recommendable.

Sequestration by IFIT1 Impairs Translation of 2′O-unmethylated Capped RNA

PubMed Central

Lacerda, Livia; Benda, Christian; Holze, Cathleen; Eberl, Christian H.; Mann, Angelika; Kindler, Eveline; Gil-Cruz, Cristina; Ziebuhr, John; Thiel, Volker; Pichlmair, Andreas

2013-01-01

Viruses that generate capped RNA lacking 2′O methylation on the first ribose are severely affected by the antiviral activity of Type I interferons. We used proteome-wide affinity purification coupled to mass spectrometry to identify human and mouse proteins specifically binding to capped RNA with different methylation states. This analysis, complemented with functional validation experiments, revealed that IFIT1 is the sole interferon-induced protein displaying higher affinity for unmethylated than for methylated capped RNA. IFIT1 tethers a species-specific protein complex consisting of other IFITs to RNA. Pulsed stable isotope labelling with amino acids in cell culture coupled to mass spectrometry as well as in vitro competition assays indicate that IFIT1 sequesters 2′O-unmethylated capped RNA and thereby impairs binding of eukaryotic translation initiation factors to 2′O-unmethylated RNA template, which results in inhibition of translation. The specificity of IFIT1 for 2′O-unmethylated RNA serves as potent antiviral mechanism against viruses lacking 2′O-methyltransferase activity and at the same time allows unperturbed progression of the antiviral program in infected cells. PMID:24098121

Acetazolamide Attenuates Lithium–Induced Nephrogenic Diabetes Insipidus

PubMed Central

de Groot, Theun; Sinke, Anne P.; Kortenoeven, Marleen L.A.; Alsady, Mohammad; Baumgarten, Ruben; Devuyst, Olivier; Loffing, Johannes; Wetzels, Jack F.

2016-01-01

To reduce lithium–induced nephrogenic diabetes insipidus (lithium-NDI), patients with bipolar disorder are treated with thiazide and amiloride, which are thought to induce antidiuresis by a compensatory increase in prourine uptake in proximal tubules. However, thiazides induced antidiuresis and alkalinized the urine in lithium-NDI mice lacking the sodium-chloride cotransporter, suggesting that inhibition of carbonic anhydrases (CAs) confers the beneficial thiazide effect. Therefore, we tested the effect of the CA–specific blocker acetazolamide in lithium-NDI. In collecting duct (mpkCCD) cells, acetazolamide reduced the cellular lithium content and attenuated lithium-induced downregulation of aquaporin-2 through a mechanism different from that of amiloride. Treatment of lithium-NDI mice with acetazolamide or thiazide/amiloride induced similar antidiuresis and increased urine osmolality and aquaporin-2 abundance. Thiazide/amiloride-treated mice showed hyponatremia, hyperkalemia, hypercalcemia, metabolic acidosis, and increased serum lithium concentrations, adverse effects previously observed in patients but not in acetazolamide-treated mice in this study. Furthermore, acetazolamide treatment reduced inulin clearance and cortical expression of sodium/hydrogen exchanger 3 and attenuated the increased expression of urinary PGE2 observed in lithium-NDI mice. These results show that the antidiuresis with acetazolamide was partially caused by a tubular-glomerular feedback response and reduced GFR. The tubular-glomerular feedback response and/or direct effect on collecting duct principal or intercalated cells may underlie the reduced urinary PGE2 levels with acetazolamide, thereby contributing to the attenuation of lithium-NDI. In conclusion, CA activity contributes to lithium-NDI development, and acetazolamide attenuates lithium-NDI development in mice similar to thiazide/amiloride but with fewer adverse effects. PMID:26574046

Evaluation of neural reflex activation as a mode of action for the acute respiratory effects of ozone.

PubMed

Prueitt, Robyn L; Goodman, Julie E

2016-09-01

Exposure to elevated levels of ozone has been associated with a variety of respiratory-related health endpoints in both epidemiology and controlled human exposure studies, including lung function decrements and airway inflammation. A mode of action (MoA) for these effects has not been established, but it has been proposed that they may occur through ozone-induced activation of neural reflexes. We critically reviewed experimental studies of ozone exposure and neural reflex activation and applied the International Programme on Chemical Safety (IPCS) mode-of-action/human relevance framework to evaluate the biological plausibility and human relevance of this proposed MoA. Based on the currently available experimental data, we found that the proposed MoA of neural reflex activation is biologically plausible for the endpoint of ozone-induced lung function decrements at high ozone exposures, but further studies are needed to fill important data gaps regarding the relevance of this MoA at lower exposures. A role for the proposed MoA in ozone-induced airway inflammation is less plausible, as the evidence is conflicting and is also of unclear relevance given the lack of studies conducted at lower exposures. The evidence suggests a different MoA for ozone-induced inflammation that may still be linked to the key events in the proposed MoA, such that neural reflex activation may have some degree of involvement in modulating ozone-induced neutrophil influx, even if it is not a direct role.

Comparison of intra-organellar chaperone capacity for dealing with stress-induced protein unfolding.

PubMed

Hageman, Jurre; Vos, Michel J; van Waarde, Maria A W H; Kampinga, Harm H

2007-11-23

Molecular chaperones are essential for cells to prevent that partially unfolded proteins form non-functional, toxic aggregates. This requirement is increased when cells experience protein unfolding stresses and such could affect all compartments in the eukaryotic cell. Whether all organelles are equipped with comparable chaperone capacities is largely unknown, mainly due to the lack of suitable reporters that allow such a comparison. Here we describe the development of fluorescent luciferase reporters that are sorted to various cellular locations (nucleus, cytoplasm, endoplasmic reticulum, and peroxisomes) and that differ minimally in their intrinsic thermal stability properties. When heating living cells, the rate of inactivation was most rapid for the nuclear-targeted luciferase, indicating that the nucleus is the most sensitive organelle toward heat-induced denaturing stress. Post-heat re-activation, however, occurred at equal kinetics irrespective of luciferase localization. Also, induction of thermotolerance by a priming heat treatment, that coordinately up-regulates all heat-inducible chaperones, resulted in a transient heat resistance of the luciferase in all organelles in a comparable manner. Overexpression of the main heat-inducible Hsp70 family member, HspA1A, protected only the cytosolic and nuclear, but not the other luciferases. Together, our data suggest that in each compartment investigated, including the peroxisome in which so far no chaperones could be detected, chaperone machines are present and can be induced with activities similar to those present in the cytosolic/nuclear compartment.

SOS response activation and competence development are antagonistic mechanisms in Streptococcus thermophilus.

PubMed

Boutry, Céline; Delplace, Brigitte; Clippe, André; Fontaine, Laetitia; Hols, Pascal

2013-02-01

Streptococcus includes species that either contain or lack the LexA-like repressor (HdiR) of the classical SOS response. In Streptococcus pneumoniae, a species which belongs to the latter group, SOS response inducers (e.g., mitomycin C [Mc] and fluoroquinolones) were shown to induce natural transformation, leading to the hypothesis that DNA damage-induced competence could contribute to genomic plasticity and stress resistance. Using reporter strains and microarray experiments, we investigated the impact of the SOS response inducers mitomycin C and norfloxacin and the role of HdiR on competence development in Streptococcus thermophilus. We show that both the addition of SOS response inducers and HdiR inactivation have a dual effect, i.e., induction of the expression of SOS genes and reduction of transformability. Reduction of transformability results from two different mechanisms, since HdiR inactivation has no major effect on the expression of competence (com) genes, while mitomycin C downregulates the expression of early and late com genes in a dose-dependent manner. The downregulation of com genes by mitomycin C was shown to take place at the level of the activation of the ComRS signaling system by an unknown mechanism. Conversely, we show that a ComX-deficient strain is more resistant to mitomycin C and norfloxacin in a viability plate assay, which indicates that competence development negatively affects the resistance of S. thermophilus to DNA-damaging agents. Altogether, our results strongly suggest that SOS response activation and competence development are antagonistic processes in S. thermophilus.

Ab Initio Study of Interfacial Structure Transformation of Amorphous Carbon Catalyzed by Ti, Cr, and W Transition Layers.

PubMed

Li, Xiaowei; Li, Lei; Zhang, Dong; Wang, Aiying

2017-11-29

Amorphous carbon (a-C) films composited with transition layers exhibit the desirable improvement of adhesion strength between films and substrate, but the further understanding on the interfacial structure transformation of a-C structure induced by transition layers is still lacked. In this paper, using ab initio calculations, we comparatively studied the interfacial structure between Ti, Cr, or W transition layers and a-C film from the atomic scale, and demonstrated that the addition of Ti, Cr, or W catalyzed the graphitic transformation of a-C structure at different levels, which provided the theoretical guidance for designing a multilayer nanocomposite film for renewed application.

Increased bone density in mice lacking the proton receptor, OGR1

PubMed Central

Krieger, Nancy S.; Yao, Zhenqiang; Kyker-Snowman, Kelly; Kim, Min Ho; Boyce, Brendan F.; Bushinsky, David A.

2016-01-01

Chronic metabolic acidosis stimulates cell-mediated calcium efflux from bone through osteoblastic prostaglandin E2-induced stimulation of RANKL leading to increased osteoclastic bone resorption. Osteoblasts express the proton-sensing G-protein coupled receptor, OGR1, which activates IP3-mediated intracellular calcium. Proton-induced osteoblastic intracellular calcium signaling requires OGR1, suggesting OGR1 is the sensor activated during acidosis to cause bone resorption. Growing mice produce large amounts of metabolic acids which must be buffered, primarily by bone, prior to excretion by the kidney. Here we tested whether lack of OGR1 inhibits proton-induced bone resorption by measuring bone mineral density by μCT and histomorphometry in 8 week old male OGR1−/− and C57/Bl6 wild type mice. OGR1−/− mice have normal skeletal development with no atypical gross phenotype. Trabecular and cortical bone volume was increased in tibiae and vertebrae from OGR1−/−. There were increased osteoblast numbers on the cortical and trabecular surfaces of tibiae from OGR1−/− mice, increased endocortical and trabecular bone formation rates, and osteoblastic gene expression. Osteoclast numbers and surface were increased in tibiae of OGR1−/− mice. Thus, in rapidly growing mice, lack of OGR1 leads to increased bone mass with increased bone turnover and a greater increase in bone formation than resorption. This supports the important role of the proton receptor, OGR1, in the response of bone to protons. PMID:26880453

Weathered MC252 crude oil-induced anemia and abnormal erythroid morphology in double-crested cormorants (Phalacrocorax auritus) with light microscopic and ultrastructural description of Heinz bodies.

PubMed

Harr, Kendal E; Cunningham, Fred L; Pritsos, Chris A; Pritsos, Karen L; Muthumalage, Thivanka; Dorr, Brian S; Horak, Katherine E; Hanson-Dorr, Katie C; Dean, Karen M; Cacela, Dave; McFadden, Andrew K; Link, Jane E; Healy, Katherine A; Tuttle, Pete; Bursian, Steven J

2017-12-01

Injury assessment of birds following the Deepwater Horizon (DWH) oil spill in 2010 was part of the Natural Resource Damage Assessment. One reported effect was hemolytic anemia with the presence of Heinz bodies (HB) in birds, however, the role of route and magnitude of exposure to oil is unknown. The purpose of the present study was to determine if double-crested cormorants (Phalacocorax auritis; DCCO) exposed orally and dermally to artificially weathered crude oil would develop hemolytic anemia including HB and reticulocytosis. In the oral experiment, sub-adult, mixed-sex DCCOs were fed control (n = 8) or oil-injected fish with a daily target dose of 5 (n = 9) or 10 (n = 9) ml oil/kg for 21 days. Then, subadult control (n = 12) and treated (n = 13) cormorant groups of similar sex-ratio were dermally treated with approximately 13ml of water or weathered MC252 crude oil, respectively, every 3 days for 6 dosages approximating 20% surface coverage. Collected whole blood samples were analyzed by light (new methylene blue) and transmission electron microscopy. Both oral and dermal treatment with weathered DWH MC252 crude oil induced regenerative, but inadequately compensated, anemia due to hemolysis and hematochezia as indicated by decreased packed cell volume, relative increase in reticulocytes with lack of difference in corrected reticulocyte count, and morphologic evidence of oxidant damage at the ultrastructural level. Hemoglobin precipitation, HB formation, degenerate organelles, and systemic oxidant damage were documented. Heinz bodies were typically <2µm in length and smaller than in mammals. These oblong cytoplasmic inclusions were difficult to see upon routine blood smear evaluation and lacked the classic button appearance found in mammalian red blood cells. They could be found as light, homogeneous blue inclusions upon new methylene blue staining. Ultrastructurally, HB appeared as homogeneous, electron-dense structures within the cytosol and lacked membranous structure. Oxidant damage in avian red blood cells results in degenerate organelles and precipitated hemoglobin or HB with different morphology than that found in mammalian red blood cells. Ultrastructural evaluation is needed to definitively identify HB and damaged organelles to confirm oxidant damage. The best field technique based on the data in this study is assessment of PCV with storage of blood in glutaraldehyde for possible TEM analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

Depletion of angiotensin-converting enzyme 2 reduces brain serotonin and impairs the running-induced neurogenic response.

PubMed

Klempin, Friederike; Mosienko, Valentina; Matthes, Susann; Villela, Daniel C; Todiras, Mihail; Penninger, Josef M; Bader, Michael; Santos, Robson A S; Alenina, Natalia

2018-04-20

Physical exercise induces cell proliferation in the adult hippocampus in rodents. Serotonin (5-HT) and angiotensin (Ang) II are important mediators of the pro-mitotic effect of physical activity. Here, we examine precursor cells in the adult brain of mice lacking angiotensin-converting enzyme (ACE) 2, and explore the effect of an acute running stimulus on neurogenesis. ACE2 metabolizes Ang II to Ang-(1-7) and is essential for the intestinal uptake of tryptophan (Trp), the 5-HT precursor. In ACE2-deficient mice, we observed a decrease in brain 5-HT levels and no increase in the number of BrdU-positive cells following exercise. Targeting the Ang II/AT1 axis by blocking the receptor, or experimentally increasing Trp/5-HT levels in the brain of ACE2-deficient mice, did not rescue the running-induced effect. Furthermore, mice lacking the Ang-(1-7) receptor, Mas, presented a normal neurogenic response to exercise. Our results identify ACE2 as a novel factor required for exercise-dependent modulation of adult neurogenesis and essential for 5-HT metabolism.

Downregulation of Pink1 influences mitochondrial fusion–fission machinery and sensitizes to neurotoxins in dopaminergic cells

PubMed Central

Rojas-Charry, Liliana; Cookson, Mark R.; Niño, Andrea; Arboleda, Humberto; Arboleda, Gonzalo

2016-01-01

It is now well established that mitochondria are organelles that, far from being static, are subject to a constant process of change. This process, which has been called mitochondrial dynamics, includes processes of both fusion and fission. Loss of Pink1 (PTEN-induced putative kinase 1) function is associated with early onset recessive Parkinson’s disease and it has been proposed that mitochondrial dynamics might be affected by loss of the mitochondrial kinase. Here, we report the effects of silencing Pink1 on mitochondrial fusion and fission events in dopaminergic neuron cell lines. Cells lacking Pink1 were more sensitive to cell death induced by C2-Ceramide, which inhibits proliferation and induces apoptosis. In the same cell lines, mitochondrial morphology was fragmented and this was enhanced by application of forskolin, which stimulates the cAMP pathway that phosphorylates Drp1 and thereby inactivates it. Cells lacking Pink1 had lower Drp1 and Mfn2 expression. Based on these data, we propose that Pink1 may exert a neuroprotective role in part by limiting mitochondrial fission. PMID:24792327

DPP8 and DPP9 inhibition induces pro-caspase-1-dependent monocyte and macrophage pyroptosis.

PubMed

Okondo, Marian C; Johnson, Darren C; Sridharan, Ramya; Go, Eun Bin; Chui, Ashley J; Wang, Mitchell S; Poplawski, Sarah E; Wu, Wengen; Liu, Yuxin; Lai, Jack H; Sanford, David G; Arciprete, Michael O; Golub, Todd R; Bachovchin, William W; Bachovchin, Daniel A

2017-01-01

Val-boroPro (Talabostat, PT-100), a nonselective inhibitor of post-proline cleaving serine proteases, stimulates mammalian immune systems through an unknown mechanism of action. Despite this lack of mechanistic understanding, Val-boroPro has attracted substantial interest as a potential anticancer agent, reaching phase 3 trials in humans. Here we show that Val-boroPro stimulates the immune system by triggering a proinflammatory form of cell death in monocytes and macrophages known as pyroptosis. We demonstrate that the inhibition of two serine proteases, DPP8 and DPP9, activates the pro-protein form of caspase-1 independent of the inflammasome adaptor ASC. Activated pro-caspase-1 does not efficiently process itself or IL-1β but does cleave and activate gasdermin D to induce pyroptosis. Mice lacking caspase-1 do not show immune stimulation after treatment with Val-boroPro. Our data identify what is to our knowledge the first small molecule that induces pyroptosis and reveals a new checkpoint that controls the activation of the innate immune system.

The effect of age at exposure on the inactivating mechanisms and relative contributions of key tumor suppressor genes in radiation-induced mouse T-cell lymphomas.

PubMed

Sunaoshi, Masaaki; Amasaki, Yoshiko; Hirano-Sakairi, Shinobu; Blyth, Benjamin J; Morioka, Takamitsu; Kaminishi, Mutsumi; Shang, Yi; Nishimura, Mayumi; Shimada, Yoshiya; Tachibana, Akira; Kakinuma, Shizuko

2015-09-01

Children are considered more sensitive to radiation-induced cancer than adults, yet any differences in genomic alterations associated with age-at-exposure and their underlying mechanisms remain unclear. We assessed genome-wide DNA copy number and mutation of key tumor suppressor genes in T-cell lymphomas arising after weekly irradiation of female B6C3F1 mice with 1.2Gy X-rays for 4 consecutive weeks starting during infancy (1 week old), adolescence (4 weeks old) or as young adults (8 weeks old). Although T-cell lymphoma incidence was similar, loss of heterozygosity at Cdkn2a on chromosome 4 and at Ikaros on chromosome 11 was more frequent in the two older groups, while loss at the Pten locus on chromosome 19 was more frequent in the infant-irradiated group. Cdkn2a and Ikaros mutation/loss was a common feature of the young adult-irradiation group, with Ikaros frequently (50%) incurring multiple independent hits (including deletions and mutations) or suffering a single hit predicted to result in a dominant negative protein (such as those lacking exon 4, an isoform we have designated Ik12, which lacks two DNA binding zinc-finger domains). Conversely, Pten mutations were more frequent after early irradiation (60%) than after young adult-irradiation (30%). Homozygous Pten mutations occurred without DNA copy number change after irradiation starting in infancy, suggesting duplication of the mutated allele by chromosome mis-segregation or mitotic recombination. Our findings demonstrate that while deletions on chromosomes 4 and 11 affecting Cdkn2a and Ikaros are a prominent feature of young adult irradiation-induced T-cell lymphoma, tumors arising after irradiation from infancy suffer a second hit in Pten by mis-segregation or recombination. This is the first report showing an influence of age-at-exposure on genomic alterations of tumor suppressor genes and their relative involvement in radiation-induced T-cell lymphoma. These data are important for considering the risks associated with childhood exposure to radiation. Copyright © 2015 Elsevier B.V. All rights reserved.

Ex vivo evaluation of antifibrotic compounds in skin scarring: EGCG and silencing of PAI-1 independently inhibit growth and induce keloid shrinkage.

PubMed

Syed, Farhatullah; Bagabir, Rania A; Paus, Ralf; Bayat, Ardeshir

2013-08-01

Keloid disease (KD) is a common fibroproliferative disorder of unknown etiopathogenesis. Its unique occurrence in human skin and lack of animal models pose challenges for KD research. The lack of a suitable model in KD and over-reliance on cell culture has hampered the progress in developing new treatments. Therefore, we evaluated the effect of two promising candidate antifibrotic therapies: (-)-epigallocatechin-3-gallate (EGCG) and plasminogen activator inhibitor-1 (PAI-1) silencing in a long-term human keloid organ culture (OC). Four millimeters of air-liquid interface (ALI) keloid explants on collagen gel matrix in serum-free medium (n=8 cases) were treated with different modalities (EGCG treatment; PAI-1 knockdown by short interfering RNA (siRNA) and application of dexamethasone (DEX) as control). Normal skin (n=6) was used as control (only for D0 keloid-untreated comparison). Besides routine histology and quantitative (immuno-) histomorphometry, the key phenotypic and growth parameters of KD were assessed. Results demonstrated that EGCG reduced keloid volume significantly (40% by week 4), increased apoptosis (≥40% from weeks 1 to 4), and decreased proliferation (≤17% in week 2). EGCG induced epidermal shrinkage, reduced collagen-I and -III at mRNA and protein levels, depleted 98% of keloid-associated mast cells, and reduced the percentage of both cellularity and blood vessel count by week 4. Knockdown of PAI-1 significantly reduced keloid volume by 28% in week 4, respectively, and reduced collagen-I and -III at both mRNA and protein levels. As expected, DEX increased keloid apoptosis, decreased keloid proliferation, and collagen synthesis, but induced connective tissue growth factor overexpression. In conclusion, using keloid OC model, we provide the first functional evidence for testing candidate antifibrotic compounds in KD. We show that EGCG and PAI-1 silencing effectively inhibits growth and induces shrinkage of human keloid tissue in situ. Therefore, the application of EGCG, PAI-1 silencing, and other emerging compounds tested using this model may provide effective treatment and potentially aid in the prevention of recurrence of KD following surgery.

Effects of various types of stress on the metabolism of reserve carbohydrates in Saccharomyces cerevisiae: genetic evidence for a stress-induced recycling of glycogen and trehalose.

PubMed

Parrou, J L; Teste, M A; François, J

1997-06-01

It is well known that glycogen and trehalose accumulate in yeast under nutrient starvation or entering into the stationary phase of growth, and that high levels of trehalose are found in heat-shocked cells. However, effects of various types of stress on trehalose, and especially on glycogen, are poorly documented. Taking into account that almost all genes encoding the enzymes involved in the metabolism of these two reserve carbohydrates contain between one and several copies of the stress-responsive element (STRE), an investigation was made of the possibility of a link between the potential transcriptional induction of these genes and the accumulation of glycogen and trehalose under different stress conditions. Using transcriptional fusions, it was found that all these genes were induced in a similar fashion, although to various extents, by temperature, osmotic and oxidative stresses. Experiments performed with an msn2/msn4 double mutant proved that the transcriptional induction of the genes encoding glycogen synthase (GSY2) and trehalose-6-phosphate synthase (TPS1) was needed for the small increase in glycogen and trehalose upon exposure to a mild heat stress and salt shock. However, the extent of transcriptional activation of these genes upon stresses in wild-type strains was not correlated with a proportional rise in either glycogen or trehalose. The major explanation for this lack of correlation comes from the fact that genes encoding the enzymes of the biosynthetic and of the biodegradative pathways were almost equally induced. Hence, trehalose and glycogen accumulated to much higher levels in cells lacking neutral trehalose or glycogen phosphorylase exposed to stress conditions, which suggested that one of the major effects of stress in yeast is to induce a wasteful expenditure of energy by increasing the recycling of these molecules. We also found that transcriptional induction of STRE-controlled genes was abolished at temperatures above 40 degree C, while induction was still observed for a heat-shock-element regulated gene. Remarkably, trehalose accumulated to very high levels under this condition. This can be explained by a stimulation of trehalose synthase and inhibition of trehalose by high temperature.

Elevated FGF23 Levels in Mice Lacking the Thiazide-Sensitive NaCl cotransporter (NCC).

PubMed

Pathare, Ganesh; Anderegg, Manuel; Albano, Giuseppe; Lang, Florian; Fuster, Daniel G

2018-02-26

Fibroblast growth factor 23 (FGF23) participates in the orchestration of mineral metabolism by inducing phosphaturia and decreasing the production of 1,25(OH) 2 D 3 . It is known that FGF23 release is stimulated by aldosterone and extracellular volume depletion. To characterize this effect further in a model of mild hypovolemia, we studied mice lacking the thiazide sensitive NaCl cotransporter (NCC). Our data indicate that NCC knockout mice (KO) have significantly higher FGF23, PTH and aldosterone concentrations than corresponding wild type (WT) mice. However, 1,25(OH) 2 D 3 , fractional phosphate excretion and renal brush border expression of the sodium/phosphate co-transporter 2a were not different between the two genotypes. In addition, renal expression of FGF23 receptor FGFR1 and the co-receptor Klotho were unaltered in NCC KO mice. FGF23 transcript was increased in the bone of NCC KO mice compared to WT mice, but treatment of primary murine osteoblasts with the NCC inhibitor hydrochlorothiazide did not elicit an increase of FGF23 transcription. In contrast, the mineralocorticoid receptor blocker eplerenone reversed excess FGF23 levels in KO mice but not in WT mice, indicating that FGF23 upregulation in NCC KO mice is primarily aldosterone-mediated. Together, our data reveal that lack of renal NCC causes an aldosterone-mediated upregulation of circulating FGF23.

Genomic Analysis Reveals Contrasting PIFq Contribution to Diurnal Rhythmic Gene Expression in PIF-Induced and -Repressed Genes.

PubMed

Martin, Guiomar; Soy, Judit; Monte, Elena

2016-01-01

Members of the PIF quartet (PIFq; PIF1, PIF3, PIF4, and PIF5) collectively contribute to induce growth in Arabidopsis seedlings under short day (SD) conditions, specifically promoting elongation at dawn. Their action involves the direct regulation of growth-related and hormone-associated genes. However, a comprehensive definition of the PIFq-regulated transcriptome under SD is still lacking. We have recently shown that SD and free-running (LL) conditions correspond to "growth" and "no growth" conditions, respectively, correlating with greater abundance of PIF protein in SD. Here, we present a genomic analysis whereby we first define SD-regulated genes at dawn compared to LL in the wild type, followed by identification of those SD-regulated genes whose expression depends on the presence of PIFq. By using this sequential strategy, we have identified 349 PIF/SD-regulated genes, approximately 55% induced and 42% repressed by both SD and PIFq. Comparison with available databases indicates that PIF/SD-induced and PIF/SD-repressed sets are differently phased at dawn and mid-morning, respectively. In addition, we found that whereas rhythmicity of the PIF/SD-induced gene set is lost in LL, most PIF/SD-repressed genes keep their rhythmicity in LL, suggesting differential regulation of both gene sets by the circadian clock. Moreover, we also uncovered distinct overrepresented functions in the induced and repressed gene sets, in accord with previous studies in other examined PIF-regulated processes. Interestingly, promoter analyses showed that, whereas PIF/SD-induced genes are enriched in direct PIF targets, PIF/SD-repressed genes are mostly indirectly regulated by the PIFs and might be more enriched in ABA-regulated genes.

Trigeminal Proprioception Evoked by Strong Stretching of the Mechanoreceptors in Müller's Muscle Induces Reflex Contraction of the Orbital Orbicularis Oculi Slow-Twitch Muscle Fibers.

PubMed

Matsuo, Kiyoshi; Ban, Ryokuya; Ban, Midori; Yuzuriha, Shunsuke

2014-01-01

The mixed orbicularis oculi muscle lacks an intramuscular proprioceptive system such as muscle spindles, to induce reflex contraction of its slow-twitch fibers. We evaluated whether the mechanoreceptors in Müller's muscle function as extrinsic mechanoreceptors to induce reflex contraction of the slow-twitch fibers of the orbicularis oculi in addition to those of the levator and frontalis muscles. We evaluated in patients with aponeurosis-disinserted blepharoptosis whether strong stretching of the mechanoreceptors in Müller's muscle from upgaze with unilateral lid load induced reflex contraction of the orbicularis oculi slow-twitch fibers and whether anesthesia of Müller's muscle precluded the contraction. We compared the electromyographic responses of the bilateral orbicularis oculi muscles to unilateral intraoperative direct stimulation of the trigeminal proprioceptive nerve with those to unilateral transcutaneous electrical stimulation of the supraorbital nerve. Upgaze with a unilateral 3-g lid load induced reflex contraction of the bilateral orbicularis oculi muscles with ipsilateral dominance. Anesthesia of Müller's muscle precluded the reflex contraction. The orbicularis oculi reflex evoked by stimulation of the trigeminal proprioceptive nerve differed from that by electrical stimulation of the supraorbital nerve in terms of the intensity of current required to induce the reflex, the absence of R1, and duration. The mechanoreceptors in Müller's muscle functions as an extramuscular proprioceptive system to induce reflex contraction of the orbital orbicularis oculi slow-twitch fibers. Whereas reflex contraction of the pretarsal orbicularis fast-twitch fibers functions in spontaneous or reflex blinking, that of the orbital orbicularis oculi slow-twitch fibers may factor in grimacing and blepharospasm.

Trigeminal Proprioception Evoked by Strong Stretching of the Mechanoreceptors in Müller's Muscle Induces Reflex Contraction of the Orbital Orbicularis Oculi Slow-Twitch Muscle Fibers

PubMed Central

Ban, Ryokuya; Ban, Midori; Yuzuriha, Shunsuke

2014-01-01

Objective: The mixed orbicularis oculi muscle lacks an intramuscular proprioceptive system such as muscle spindles, to induce reflex contraction of its slow-twitch fibers. We evaluated whether the mechanoreceptors in Müller's muscle function as extrinsic mechanoreceptors to induce reflex contraction of the slow-twitch fibers of the orbicularis oculi in addition to those of the levator and frontalis muscles. Methods: We evaluated in patients with aponeurosis-disinserted blepharoptosis whether strong stretching of the mechanoreceptors in Müller's muscle from upgaze with unilateral lid load induced reflex contraction of the orbicularis oculi slow-twitch fibers and whether anesthesia of Müller's muscle precluded the contraction. We compared the electromyographic responses of the bilateral orbicularis oculi muscles to unilateral intraoperative direct stimulation of the trigeminal proprioceptive nerve with those to unilateral transcutaneous electrical stimulation of the supraorbital nerve. Results: Upgaze with a unilateral 3-g lid load induced reflex contraction of the bilateral orbicularis oculi muscles with ipsilateral dominance. Anesthesia of Müller's muscle precluded the reflex contraction. The orbicularis oculi reflex evoked by stimulation of the trigeminal proprioceptive nerve differed from that by electrical stimulation of the supraorbital nerve in terms of the intensity of current required to induce the reflex, the absence of R1, and duration. Conclusions: The mechanoreceptors in Müller's muscle functions as an extramuscular proprioceptive system to induce reflex contraction of the orbital orbicularis oculi slow-twitch fibers. Whereas reflex contraction of the pretarsal orbicularis fast-twitch fibers functions in spontaneous or reflex blinking, that of the orbital orbicularis oculi slow-twitch fibers may factor in grimacing and blepharospasm. PMID:25210572

Boxer crabs induce asexual reproduction of their associated sea anemones by splitting and intraspecific theft.

PubMed

Schnytzer, Yisrael; Giman, Yaniv; Karplus, Ilan; Achituv, Yair

2017-01-01

Crabs of the genus Lybia have the remarkable habit of holding a sea anemone in each of their claws. This partnership appears to be obligate, at least on the part of the crab. The present study focuses on Lybia leptochelis from the Red Sea holding anemones of the genus Alicia (family Aliciidae). These anemones have not been found free living, only in association with L. leptochelis . In an attempt to understand how the crabs acquire them, we conducted a series of behavioral experiments and molecular analyses. Laboratory observations showed that the removal of one anemone from a crab induces a "splitting" behavior, whereby the crab tears the remaining anemone into two similar parts, resulting in a complete anemone in each claw after regeneration. Furthermore, when two crabs, one holding anemones and one lacking them, are confronted, the crabs fight, almost always leading to the "theft" of a complete anemone or anemone fragment by the crab without them. Following this, crabs "split" their lone anemone into two. Individuals of Alicia sp. removed from freshly collected L. leptochelis were used for DNA analysis. By employing AFLP (Fluorescence Amplified Fragments Length Polymorphism) it was shown that each pair of anemones from a given crab is genetically identical. Furthermore, there is genetic identity between most pairs of anemone held by different crabs, with the others showing slight genetic differences. This is a unique case in which one animal induces asexual reproduction of another, consequently also affecting its genetic diversity.

Molecular and Proteomic Analysis of Levofloxacin and Metronidazole Resistant Helicobacter pylori.

PubMed

Hanafi, Aimi; Lee, Woon Ching; Loke, Mun Fai; Teh, Xinsheng; Shaari, Ain; Dinarvand, Mojdeh; Lehours, Philippe; Mégraud, Francis; Leow, Alex Hwong Ruey; Vadivelu, Jamuna; Goh, Khean Lee

2016-01-01

Antibiotic resistance in bacteria incurs fitness cost, but compensatory mechanisms may ameliorate the cost and sustain the resistance even under antibiotics-free conditions. The aim of this study was to determine compensatory mechanisms of antibiotic resistance in H. pylori . Five strains of levofloxacin-sensitive H. pylori were induced in vitro to develop resistance. In addition, four pairs of metronidazole-sensitive and -resistant H. pylori strains were isolated from patients carrying dual H. pylori populations that consist of both sensitive and resistant phenotypes. Growth rate, virulence and biofilm-forming ability of the sensitive and resistant strains were compared to determine effects of compensatory response. Proteome profiles of paired sensitive and resistant strains were analyzed by liquid chromatography/mass spectrophotometry (LC/MS). Although there were no significant differences in growth rate between sensitive and resistant pairs, bacterial virulence (in terms of abilities to induce apoptosis and form biofilm) differs from pair to pair. These findings demonstrate the complex and strain-specific phenotypic changes in compensation for antibiotics resistance. Compensation for in vitro induced levofloxacin resistance involving mutations of gyrA and gyrB was functionally random. Furthermore, higher protein translation and non-functional protein degradation capabilities in naturally-occuring dual population metronidazole sensitive-resistant strains may be a possible alternative mechanism underlying resistance to metronidazole without mutations in rdxA and frxA . This may explain the lack of mutations in target genes in ~10% of metronidazole resistant strains.

Molecular and Proteomic Analysis of Levofloxacin and Metronidazole Resistant Helicobacter pylori

PubMed Central

Hanafi, Aimi; Lee, Woon Ching; Loke, Mun Fai; Teh, Xinsheng; Shaari, Ain; Dinarvand, Mojdeh; Lehours, Philippe; Mégraud, Francis; Leow, Alex Hwong Ruey; Vadivelu, Jamuna; Goh, Khean Lee

2016-01-01

Antibiotic resistance in bacteria incurs fitness cost, but compensatory mechanisms may ameliorate the cost and sustain the resistance even under antibiotics-free conditions. The aim of this study was to determine compensatory mechanisms of antibiotic resistance in H. pylori. Five strains of levofloxacin-sensitive H. pylori were induced in vitro to develop resistance. In addition, four pairs of metronidazole-sensitive and -resistant H. pylori strains were isolated from patients carrying dual H. pylori populations that consist of both sensitive and resistant phenotypes. Growth rate, virulence and biofilm-forming ability of the sensitive and resistant strains were compared to determine effects of compensatory response. Proteome profiles of paired sensitive and resistant strains were analyzed by liquid chromatography/mass spectrophotometry (LC/MS). Although there were no significant differences in growth rate between sensitive and resistant pairs, bacterial virulence (in terms of abilities to induce apoptosis and form biofilm) differs from pair to pair. These findings demonstrate the complex and strain-specific phenotypic changes in compensation for antibiotics resistance. Compensation for in vitro induced levofloxacin resistance involving mutations of gyrA and gyrB was functionally random. Furthermore, higher protein translation and non-functional protein degradation capabilities in naturally-occuring dual population metronidazole sensitive-resistant strains may be a possible alternative mechanism underlying resistance to metronidazole without mutations in rdxA and frxA. This may explain the lack of mutations in target genes in ~10% of metronidazole resistant strains. PMID:28018334

RhoA, Rac1, and Cdc42 differentially regulate αSMA and collagen I expression in mesenchymal stem cells.

PubMed

Ge, Jianfeng; Burnier, Laurent; Adamopoulou, Maria; Kwa, Mei Qi; Schaks, Matthias; Rottner, Klemens; Brakebusch, Cord

2018-06-15

Mesenchymal stem cells (MSC) are suggested to be important progenitors of myofibroblasts in fibrosis. To understand the role of Rho GTPase signaling in TGFβ-induced myofibroblast differentiation of MSC, we generated a novel MSC line and its descendants lacking functional Rho GTPases and Rho GTPase signaling components. Unexpectedly, our data revealed that Rho GTPase signaling is required for TGFβ-induced expression of α-smooth muscle actin (αSMA) but not of collagen I α1 ( col1a1 ). Whereas loss of RhoA and Cdc42 reduced αSMA expression, ablation of the Rac1 gene had the opposite effect. Although actin polymerization and MRTFa were crucial for TGFβ-induced αSMA expression, neither Arp2/3-dependent actin polymerization nor cofilin-dependent severing and depolymerization of F-actin were required. Instead, F-actin levels were dependent on cell contraction, and TGFβ-induced actin polymerization correlated with increased cell contraction mediated by RhoA and Cdc42. Finally, we observed impaired collagen I secretion in MSC lacking RhoA or Cdc42. These data give novel molecular insights into the role of Rho GTPases in TGFβ signaling and have implications for our understanding of MSC function in fibrosis. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

A simple and powerful approach for isolation of Arabidopsis mutants with increased tolerance to H2O2-induced cell death.

PubMed

Gechev, Tsanko; Mehterov, Nikolay; Denev, Iliya; Hille, Jacques

2013-01-01

A genetic approach is described to isolate mutants more tolerant to oxidative stress. A collection of T-DNA activation tag Arabidopsis thaliana mutant lines was screened for survivors under conditions that trigger H2O2-induced cell death. Oxidative stress was induced by applying the catalase (CAT) inhibitor aminotriazole (AT) in the growth media, which results in decrease in CAT enzyme activity, H2O2 accumulation, and subsequent plant death. One mutant was recovered from the screening and named oxr1 (oxidative stress resistant 1). The location of the T-DNA insertion was identified by TAIL-PCR. Oxr1 exhibited lack of cell death symptoms and more fresh weight and chlorophyll content compared to wild type. The lack of cell death correlated with more prominent induction of anthocyanins synthesis in oxr1. These results demonstrate the feasibility of AT as a screening agent for the isolation of oxidative stress-tolerant mutants and indicate a possible protective role for anthocyanins against AT-induced cell death. The chapter includes protocols for ethyl methanesulfonate mutagenesis, mutant screening using AT, T-DNA identification by TAIL-PCR, CAT activity measurements, and determination of malondialdehyde, chlorophyll, and anthocyanins. Copyright © 2013 Elsevier Inc. All rights reserved.

Tyk2 as a target for immune regulation in human viral/bacterial pneumonia.

PubMed

Berg, Johanna; Zscheppang, Katja; Fatykhova, Diana; Tönnies, Mario; Bauer, Torsten T; Schneider, Paul; Neudecker, Jens; Rückert, Jens C; Eggeling, Stephan; Schimek, Maria; Gruber, Achim D; Suttorp, Norbert; Hippenstiel, Stefan; Hocke, Andreas C

2017-07-01

The severity and lethality of influenza A virus (IAV) infections is frequently aggravated by secondary bacterial pneumonia. However, the mechanisms in human lung tissue that provoke this increase in fatality are unknown and therapeutic immune modulatory options are lacking.We established a human lung ex vivo co-infection model to investigate innate immune related mechanisms contributing to the susceptibility of secondary pneumococcal pneumonia.We revealed that type I and III interferon (IFN) inhibits Streptococcus pneumoniae -induced interleukin (IL)-1β release. The lack of IL-1β resulted in the repression of bacterially induced granulocyte-macrophage colony-stimulating factor (GM-CSF) liberation. Specific inhibition of IFN receptor I and III-associated tyrosine kinase 2 (Tyk2) completely restored the S. pneumoniae -induced IL-1β-GM-CSF axis, leading to a reduction of bacterial growth. A preceding IAV infection of the human alveolus leads to a type I and III IFN-dependent blockade of the early cytokines IL-1β and GM-CSF, which are key for orchestrating an adequate innate immune response against bacteria. Their virally induced suppression may result in impaired bacterial clearance and alveolar repair.Pharmacological inhibition of Tyk2 might be a new treatment option to sustain beneficial endogenous GM-CSF levels in IAV-associated secondary bacterial pneumonia. Copyright ©ERS 2017.

XBP1-LOX Axis is critical in ER stress-induced growth of lung adenocarcinoma in 3D culture.

PubMed

Yang, Yi; Cheng, Bai-Jun; Jian, Hong; Chen, Zhi-Wei; Zhao, Yi; Yu, Yong-Feng; Li, Zi-Ming; Liao, Mei-Lin; Lu, Shun

2017-01-01

Rapid growth of tumor cells needs to consume large amounts of oxygen and glucose, due to lack of blood supply within the tumor, cells live in an environment that lack of oxygen and nutrients. This environment results in endoplasmic reticulum (ER) stress and activates the UPR (unfolded protein response). More and more evidence suggests UPR provides a growth signal pathway required for tumor growth. In the present study, we investigated the relationship between XBP1, one transcription factor in UPR, and the expression of LOX. We found that ER stress induces high expression of XBP1, one transcription factor in UPR, in both 2D culture and 3D culture; but only promotes growth of lung adenocarcinoma cells in in vitro 3D culture other than 2D culture. In 3D culture, we further showed that knockdown XBP1 expression can block Tm/Tg-induced cell growth. LOX genes may be key downstream effector of XBP1. Knockdown LOX expression can partially block XBP1-induced cell growth. Then we showed XBP1 suppressed by RNA interference (RNAi) can reduce the expression of LOX. For the first time, it is being shown that XBP1 can regulate the expression of LOX to promote cell growth.

Anti-nociceptive effect of methanol extract of leaves of Senna singueana in mice.

PubMed

Hishe, Hailemichael Zeru; Ambech, Tamrat Abate; Hiben, Mebrahtom Gebrelibanos; Fanta, Biruk Sintayehu

2018-05-10

Senna singueana (Del.) Lock (Fabaceae) is a shrub or tree found in Ethiopia and other African countries. It has been traditionally used for different conditions including treatment of pain conditions in humans and animals. Although various reports are available in the literature claiming different activities of the plant, scientific studies supporting analgesic potential of S. singueana are lacking and the present study aimed to investigate the antinociceptive effect of methanol extract of leaves of S. singueana in mice. Anti-nociceptive activity of S. singueana (200 mg/kg and 400 mg/kg, p.o) was investigated using acetic acid-induced writhing, formalin-induced paw licking, and hot plate tests. Acute oral toxicity was determined using a slightly modified guideline (423) of the Organization for Economic Cooperation and Development. S. singueana extract increased the percentage of inhibition of writhing response and licking response (neurogenic and inflammatory phase) in acetic acid-induced writhing and formalin-induced paw licking tests, respectively. It also significantly (p ≤ 0.05) increased the percentage of mean maximal effect (%MPE) compared to control group in the hot-plate test. In all models, the combination of S. singueana with either diclofenac or morphine produced statistically significant increase (p ≤ 0.05) in the percentage of inhibition of writhing, paw licking, and %MPE compared to single treatment groups. It was also found that the 400 mg/kg extract produced higher antinociceptive effects (p ≤ 0.05) compared to the 200 mg/kg. S. singueana leaves may have analgesic effect that is mediated through both peripheral and central mechanisms and could be used as adjuvant treatment to the modern analgesics. Copyright © 2018 Elsevier B.V. All rights reserved.

Visual and vestibular components of motion sickness.

PubMed

Eyeson-Annan, M; Peterken, C; Brown, B; Atchison, D

1996-10-01

The relative importance of visual and vestibular information in the etiology of motion sickness (MS) is not well understood, but these factors can be manipulated by inducing Coriolis and pseudo-Coriolis effects in experimental subjects. We hypothesized that visual and vestibular information are equivalent in producing MS. The experiments reported here aim, in part, to examine the relative influence of Coriolis and pseudo-Coriolis effects in inducing MS. We induced MS symptoms by combinations of whole body rotation and tilt, and environment rotation and tilt, in 22 volunteer subjects. Subjects participated in all of the experiments with at least 2 d between each experiment to dissipate after-effects. We recorded MS signs and symptoms when only visual stimulation was applied, when only vestibular stimulation was applied, and when both visual and vestibular stimulation were applied under specific conditions of whole body and environmental tilt. Visual stimuli produced more symptoms of MS than vestibular stimuli when only visual or vestibular stimuli were used (ANOVA F = 7.94, df = 1, 21 p = 0.01), but there was no significant difference in MS production when combined visual and vestibular stimulation were used to produce the Coriolis effect or pseudo-Coriolis effect (ANOVA: F = 0.40, df = 1, 21 p = 0.53). This was further confirmed by examination of the order in which the symptoms occurred and the lack of a correlation between previous experience and visually induced MS. Visual information is more important than vestibular input in causing MS when these stimuli are presented in isolation. In conditions where both visual and vestibular information are present, cross-coupling appears to occur between the pseudo-Coriolis effect and the Coriolis effect, as these two conditions are not significantly different in producing MS symptoms.

Investigation of uterotonic properties of Ananas comosus extracts.

PubMed

Monji, Faezeh; Adaikan, P Ganesan; Lau, Lang Chu; Bin Said, Baharudin; Gong, Yinhan; Tan, Huey Min; Choolani, Mahesh

2016-12-04

In folklore medicine Ananas comosus (pineapple) is reputed to act as an abortifacient and in expectant women as a means of inducing labor. Several reports have claimed abortifacient property of A. comosus fruit (ripe or unripe). Ripe fruit has been used orally as traditional medicine in inducing abortion in Kerala state of India while the juice of unripe fruit was used for abortion in Bangladesh. However, scientific evidence supporting the efficacy of pineapple extracts in inducing uterine contractions is clearly lacking. This study investigated the pharmacological effects of different fractions of pineapple extract with a range of maturities to identify the most potent uterotonic fraction. The ethanolic crude extracts of pineapple (edible part) were prepared and fractionated through a series of liquid-liquid partitions. Fractions were separately tested on isolated uterine muscle from pregnant SD rats and human pregnant myometrium, which were cut into strips along the longitudinal axis of uterus. The strips were mounted vertically in organ baths (37°C) and exposed to cumulative addition of fractions (0.1-10mgml -1 ), serotonin (0.05-5µM) and different inhibitors to delineate the mechanism of action of the active ingredients of the extract. Aqueous fraction (F4) possesses uterine stimulant property which was blocked by verapamil but unaffected by indomethacin, prazosin and atosiban. Notably, ketanserin (10µM) diminished the maximal contractile response induced by both F4 and 5HT by 74.3% and 92.1% respectively. These results may indicate the presence of 5HT or 5HT-like compound(s) and serotonergic pathways may contribute to the uterotonic activity of pineapple extract. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Mated Drosophila melanogaster females consume more amino acids during the dark phase

PubMed Central

Uchizono, Shun; Tabuki, Yumi; Kawaguchi, Natsumi; Tanimura, Teiichi; Itoh, Taichi Q.

2017-01-01

To maintain homeostasis, animals must ingest appropriate quantities, determined by their internal nutritional state, of suitable nutrients. In the fruit fly Drosophila melanogaster, an amino acid deficit induces a specific appetite for amino acids and thus results in their increased consumption. Although multiple processes of physiology, metabolism, and behavior are under circadian control in many organisms, it is unclear whether the circadian clock also modulates such motivated behavior driven by an internal need. Differences in levels of amino acid consumption by flies between the light and dark phases of the day:night cycle were examined using a capillary feeder assay following amino acid deprivation. Female flies exhibited increased consumption of amino acids during the dark phase compared with the light phase. Investigation of mutants lacking a functional period gene (per0), a well-characterized clock gene in Drosophila, found no difference between the light and dark phases in amino acid consumption by per0 flies. Furthermore, increased consumption of amino acids during the dark phase was observed in mated but not in virgin females, which strongly suggested that mating is involved in the rhythmic modulation of amino acid intake. Egg production, which is induced by mating, did not affect the rhythmic change in amino acid consumption, although egg-laying behavior showed a per0-dependent change in rhythm. Elevated consumption of amino acids during the dark phase was partly induced by the action of a seminal protein, sex peptide (SP), on the sex peptide receptor (SPR) in females. Moreover, we showed that the increased consumption of amino acids during the dark phase is induced in mated females independently of their internal level of amino acids. These results suggest that a post-mating SP/SPR signal elevates amino acid consumption during the dark phase via the circadian clock. PMID:28241073

Mated Drosophila melanogaster females consume more amino acids during the dark phase.

PubMed

Uchizono, Shun; Tabuki, Yumi; Kawaguchi, Natsumi; Tanimura, Teiichi; Itoh, Taichi Q

2017-01-01

To maintain homeostasis, animals must ingest appropriate quantities, determined by their internal nutritional state, of suitable nutrients. In the fruit fly Drosophila melanogaster, an amino acid deficit induces a specific appetite for amino acids and thus results in their increased consumption. Although multiple processes of physiology, metabolism, and behavior are under circadian control in many organisms, it is unclear whether the circadian clock also modulates such motivated behavior driven by an internal need. Differences in levels of amino acid consumption by flies between the light and dark phases of the day:night cycle were examined using a capillary feeder assay following amino acid deprivation. Female flies exhibited increased consumption of amino acids during the dark phase compared with the light phase. Investigation of mutants lacking a functional period gene (per0), a well-characterized clock gene in Drosophila, found no difference between the light and dark phases in amino acid consumption by per0 flies. Furthermore, increased consumption of amino acids during the dark phase was observed in mated but not in virgin females, which strongly suggested that mating is involved in the rhythmic modulation of amino acid intake. Egg production, which is induced by mating, did not affect the rhythmic change in amino acid consumption, although egg-laying behavior showed a per0-dependent change in rhythm. Elevated consumption of amino acids during the dark phase was partly induced by the action of a seminal protein, sex peptide (SP), on the sex peptide receptor (SPR) in females. Moreover, we showed that the increased consumption of amino acids during the dark phase is induced in mated females independently of their internal level of amino acids. These results suggest that a post-mating SP/SPR signal elevates amino acid consumption during the dark phase via the circadian clock.

IκBNS induces Muc5ac expression in epithelial cells and causes airway hyper-responsiveness in murine asthma models.

PubMed

Yokota, M; Tamachi, T; Yokoyama, Y; Maezawa, Y; Takatori, H; Suto, A; Suzuki, K; Hirose, K; Takeda, K; Nakajima, H

2017-07-01

In allergic asthma, environmental allergens including house dust mite (HDM) trigger pattern recognition receptors and activate downstream signaling pathways including NF-κB pathways not only in immune cells but also in airway epithelial cells. Recent studies have shown that NF-κB activation is regulated positively or negatively depending on the cellular context by IκBNS (encoded by the gene Nfkbid), one of atypical IκB proteins, in the nucleus. Therefore, we hypothesized that IκBNS expressed in immune cells or epithelial cells is involved in the regulation of asthmatic responses. To determine the roles of IκBNS in HDM-induced asthmatic responses. Roles of IκBNS in HDM-induced airway inflammation and airway hyper-responsiveness (AHR) were examined by using IκBNS-deficient (Nfkbid -/- ) mice. Roles of IκBNS expressed in hematopoietic cells and nonhematopoietic cells were separately evaluated by bone marrow chimeric mice. Roles of IκBNS expressed in murine tracheal epithelial cells (mTECs) were examined by air-liquid interface culture. House dust mite-induced airway inflammation and AHR were exacerbated in mice lacking IκBNS in hematopoietic cells. In contrast, HDM-induced airway inflammation was exacerbated, but AHR was attenuated in mice lacking IκBNS in nonhematopoietic cells. The induction of Muc5ac, a representative mucin in asthmatic airways, was reduced in Nfkbid -/- mTEC, whereas the induction of Spdef, a master regulator of goblet cell metaplasia, was not impaired in Nfkbid -/- mTEC. Moreover, IκBNS bound to and activated the MUC5AC distal promoter in epithelial cells. IκBNS is involved in inducing Muc5ac expression in lung epithelial cells and causing AHR in HDM-induced asthma models. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Sorafenib-induced defective autophagy promotes cell death by necroptosis.

PubMed

Kharaziha, Pedram; Chioureas, Dimitris; Baltatzis, George; Fonseca, Pedro; Rodriguez, Patricia; Gogvadze, Vladimir; Lennartsson, Lena; Björklund, Ann-Charlotte; Zhivotovsky, Boris; Grandér, Dan; Egevad, Lars; Nilsson, Sten; Panaretakis, Theocharis

2015-11-10

Autophagy is one of the main cytoprotective mechanisms that cancer cells deploy to withstand the cytotoxic stress and survive the lethal damage induced by anti-cancer drugs. However, under specific conditions, autophagy may, directly or indirectly, induce cell death. In our study, treatment of the Atg5-deficient DU145 prostate cancer cells, with the multi-tyrosine kinase inhibitor, sorafenib, induces mitochondrial damage, autophagy and cell death. Molecular inhibition of autophagy by silencing ULK1 and Beclin1 rescues DU145 cells from cell death indicating that, in this setting, autophagy promotes cell death. Re-expression of Atg5 restores the lipidation of LC3 and rescues DU145 and MEF atg5-/- cells from sorafenib-induced cell death. Despite the lack of Atg5 expression and LC3 lipidation, DU145 cells form autophagosomes as demonstrated by transmission and immuno-electron microscopy, and the formation of LC3 positive foci. However, the lack of cellular content in the autophagosomes, the accumulation of long-lived proteins, the presence of GFP-RFP-LC3 positive foci and the accumulated p62 protein levels indicate that these autophagosomes may not be fully functional. DU145 cells treated with sorafenib undergo a caspase-independent cell death that is inhibited by the RIPK1 inhibitor, necrostatin-1. Furthermore, treatment with sorafenib induces the interaction of RIPK1 with p62, as demonstrated by immunoprecipitation and a proximity ligation assay. Silencing of p62 decreases the RIPK1 protein levels and renders necrostatin-1 ineffective in blocking sorafenib-induced cell death. In summary, the formation of Atg5-deficient autophagosomes in response to sorafenib promotes the interaction of p62 with RIPK leading to cell death by necroptosis.

A Generalist Herbivore Copes with Specialized Plant Defence: the Effects of Induction and Feeding by Helicoverpa armigera (Lepidoptera: Noctuidae) Larvae on Intact Arabidopsis thaliana (Brassicales) Plants.

PubMed

Zalucki, M P; Zalucki, J M; Perkins, L E; Schramm, K; Vassão, D G; Gershenzon, J; Heckel, D G

2017-06-01

Plants of the Brassicaceae are defended from feeding by generalist insects by constitutively-expressed and herbivory-induced glucosinolates (GS). We induced Arabidopsis plants 1, 16 and 24 h prior to allowing neonate larvae of the generalist Helicoverpa armigera to feed on whole plants for 72 h. These plants were subsequently retested with another group of neonates for a further 72 h. We used wild-type A. thaliana Col-0, and mutant lines lacking indolic GS, aliphatic GS or all GS. We hypothesized that larvae would not grow well on defended plants (WT) compared to those lacking GS, and would not grow well if plants had been primed or fed on for longer, due to the expected induced GS. There was survivorship on all lines suggesting H. armigera is a suitable generalist for these experiments. Larvae performed less well on wild-type and no indolic lines than on no aliphatic and no GS lines. Larvae distributed feeding damage extensively in all lines, more so on wild type and no-indolic lines. Contrary to expectations, larvae grew better on plants that had been induced for 1 to 16 h than on un-induced plants suggesting they moved to and selected less toxic plant parts within a heterogeneously defended plant. Performance declined on all lines if plants had been induced for 24 h, or had been fed upon for a further 72 h. However, contrary to expectation, individual and total GS did not increase after these two treatments. This suggests that Arabidopsis plants induce additional (not GS) defenses after longer induction periods.

The Role of Neuropeptide Y (NPY) in Uncontrolled Alcohol Drinking and Relapse Behavior Resulting from Exposure to Stressful Events

DTIC Science & Technology

2011-01-01

effects of stressors on excessive and uncontrolled drinking and relapse-like drinking. We proposed to use foot-shock as the stressor to elicit increase...did significantly increase deprivation-induced relapse-like drinking, and that this effect was more robust in mutant mice lacking the NPY Y1R. Thus...ethanol consumption using a models of excessive uncontrolled drinking, and mutant mice lacking NPY or the Y1R were more sensitive to the effects of

Up-regulated Ectonucleotidases in Fas-Associated Death Domain Protein- and Receptor-Interacting Protein Kinase 1-Deficient Jurkat Leukemia Cells Counteract Extracellular ATP/AMP Accumulation via Pannexin-1 Channels during Chemotherapeutic Drug-Induced Apoptosis.

PubMed

Boyd-Tressler, Andrea M; Lane, Graham S; Dubyak, George R

2017-07-01

Pannexin-1 (Panx1) channels mediate the efflux of ATP and AMP from cancer cells in response to induction of extrinsic apoptosis by death receptors or intrinsic apoptosis by chemotherapeutic agents. We previously described the accumulation of extracellular ATP /AMP during chemotherapy-induced apoptosis in Jurkat human leukemia cells. In this study, we compared how different signaling pathways determine extracellular nucleotide pools in control Jurkat cells versus Jurkat lines that lack the Fas-associated death domain (FADD) or receptor-interacting protein kinase 1 (RIP1) cell death regulatory proteins. Tumor necrosis factor- α induced extrinsic apoptosis in control Jurkat cells and necroptosis in FADD-deficient cells; treatment of both lines with chemotherapeutic drugs elicited similar intrinsic apoptosis. Robust extracellular ATP/AMP accumulation was observed in the FADD-deficient cells during necroptosis, but not during apoptotic activation of Panx1 channels. Accumulation of extracellular ATP/AMP was similarly absent in RIP1-deficient Jurkat cells during apoptotic responses to chemotherapeutic agents. Apoptotic activation triggered equivalent proteolytic gating of Panx1 channels in all three Jurkat cell lines. The differences in extracellular ATP/AMP accumulation correlated with cell-line-specific expression of ectonucleotidases that metabolized the released ATP/AMP. CD73 mRNA, and α β -methylene-ADP-inhibitable ecto-AMPase activity were elevated in the FADD-deficient cells. In contrast, the RIP1-deficient cells were defined by increased expression of tartrate-sensitive prostatic acid phosphatase as a broadly acting ectonucleotidase. Thus, extracellular nucleotide accumulation during regulated tumor cell death involves interplay between ATP/AMP efflux pathways and different cell-autonomous ectonucleotidases. Differential expression of particular ectonucleotidases in tumor cell variants will determine whether chemotherapy-induced activation of Panx1 channels drives accumulation of immunostimulatory ATP versus immunosuppressive adenosine within the tumor microenvironment. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

Targeted disruption of the glutaredoxin 1 gene does not sensitize adult mice to tissue injury induced by ischemia/reperfusion and hyperoxia†

PubMed Central

Ho, Ye-Shih; Xiong, Ye; Ho, Dorothy S.; Gao, Jinping; Chua, Balvin H. L.; Pai, Harish; Mieyal, John J.

2007-01-01

To understand the physiological function of glutaredoxin, a thiotransferase catalyzing the reduction of mixed disulfides of protein and glutathione (protein-SSG), we generated a line of knockout mice deficient in the cytosolic glutaredoxin 1 (Grx1). To our surprise, mice deficient in Grx1 were not more susceptible to acute oxidative insults in models of heart and lung injury induced by ischemia/reperfusion and hyperoxia, respectively; suggesting that changes in S-glutathionylation status of cytosolic proteins are not the major cause of such tissue injury. On the other hand, mouse embryonic fibroblasts (MEFs) isolated from Grx1-deficient mice displayed an increased vulnerability to diquat and paraquat, but they were not more susceptible to cell death induced by hydrogen peroxide (H2O2) and diamide. A deficiency in Grx1 also sensitized MEFs to protein S-glutathionylation in response to H2O2 treatment and retarded deglatuthionylation of the S-glutathionylated proteins, especially evident for an unspecified protein of approximately 44 kDa. Additional experiments showed that MEFs lacking Grx1 were more tolerant to apoptosis induced by tumor necrosis factor α plus actinomycin D. These findings suggest that different oxidants may damage the cells via distinct mechanisms in which Grx1-dependent de-glutathionylation may or may not be protective, and Grx1 may exert its function on specific target proteins. PMID:17893043

Lack of stress responses to long-term effects of corticosterone in Caps2 knockout mice.

PubMed

Mishima, Yuriko; Shinoda, Yo; Sadakata, Tetsushi; Kojima, Masami; Wakana, Shigeharu; Furuichi, Teiichi

2015-03-10

Chronic stress is associated with anxiety and depressive disorders, and can cause weight gain. Ca(2+)-dependent activator protein for secretion 2 (CAPS2) is involved in insulin release. Caps2 knockout (KO) mice exhibit decreased body weight, reduced glucose-induced insulin release, and abnormal psychiatric behaviors. We chronically administered the stress hormone corticosterone (CORT), which induces anxiety/depressive-like behavior and normally increases plasma insulin levels, via the drinking water for 10 weeks, and we examined the stress response in KO mice. Chronic CORT exposure inhibited stress-induced serum CORT elevation in wild-type (WT) mice, but not in KO mice. Poor weight gain in CORT-treated animals was observed until week 6 in WT mice, but persisted for the entire duration of the experiment in KO mice, although there is no difference in drug*genotype interaction. Among KO mice, food consumption was unchanged, while water consumption was higher, over the duration of the experiment in CORT-treated animals, compared with untreated animals. Moreover, serum insulin and leptin levels were increased in CORT-treated WT mice, but not in KO mice. Lastly, both WT and KO mice displayed anxiety/depressive-like behavior after CORT administration. These results suggest that Caps2 KO mice have altered endocrine responses to CORT administration, while maintaining CORT-induced anxiety/depressive-like behavior.

Immunomodulatory and Anti-Inflammatory Activities of Chicken Cathelicidin-2 Derived Peptides

PubMed Central

van Dijk, Albert; van Eldik, Mandy; Veldhuizen, Edwin J. A.; Tjeerdsma-van Bokhoven, Hanne L. M.; de Zoete, Marcel R.; Bikker, Floris J.; Haagsman, Henk P.

2016-01-01

Host Defence Peptides and derived peptides are promising classes of antimicrobial and immunomodulatory lead compounds. For this purpose we examined whether chicken cathelicidin-2 (CATH-2)-derived peptides modulate the function and inflammatory response of avian immune cells. Using a chicken macrophage cell line (HD11) we found that full-length CATH-2 dose-dependently induced transcription of chemokines CXCLi2/IL-8, MCP-3 and CCLi4/RANTES, but not of pro-inflammatory cytokine IL-1β. In addition, CATH-2 efficiently inhibited IL-1β and nitric oxide production by HD11 cells induced by different sources of lipopolysaccharides (LPS). N-terminal truncated CATH-2 derived peptides maintained the capacity to selectively induce chemokine transcription, but despite their high LPS affinity several analogs lacked LPS-neutralizing capacity. Substitution of phenylalanine residues by tryptophan introduced endotoxin neutralization capacity in inactive truncated CATH-2 derived peptides. In contrast, amino acid substitution of phenylalanine by tyrosine abrogated endotoxin neutralization activity of CATH-2 analogs. These findings support a pivotal role for aromatic residues in peptide-mediated endotoxin neutralization by CATH-2 analogs and were shown to be independent of LPS affinity. The capacity to modulate chemokine production and dampen endotoxin-induced pro-inflammatory responses in chicken immune cells implicates that small CATH-2 based peptides could serve as leads for the design of CATH-2 based immunomodulatory anti-infectives. PMID:26848845

Immunomodulatory and Anti-Inflammatory Activities of Chicken Cathelicidin-2 Derived Peptides.

PubMed

van Dijk, Albert; van Eldik, Mandy; Veldhuizen, Edwin J A; Tjeerdsma-van Bokhoven, Hanne L M; de Zoete, Marcel R; Bikker, Floris J; Haagsman, Henk P

2016-01-01

Host Defence Peptides and derived peptides are promising classes of antimicrobial and immunomodulatory lead compounds. For this purpose we examined whether chicken cathelicidin-2 (CATH-2)-derived peptides modulate the function and inflammatory response of avian immune cells. Using a chicken macrophage cell line (HD11) we found that full-length CATH-2 dose-dependently induced transcription of chemokines CXCLi2/IL-8, MCP-3 and CCLi4/RANTES, but not of pro-inflammatory cytokine IL-1β. In addition, CATH-2 efficiently inhibited IL-1β and nitric oxide production by HD11 cells induced by different sources of lipopolysaccharides (LPS). N-terminal truncated CATH-2 derived peptides maintained the capacity to selectively induce chemokine transcription, but despite their high LPS affinity several analogs lacked LPS-neutralizing capacity. Substitution of phenylalanine residues by tryptophan introduced endotoxin neutralization capacity in inactive truncated CATH-2 derived peptides. In contrast, amino acid substitution of phenylalanine by tyrosine abrogated endotoxin neutralization activity of CATH-2 analogs. These findings support a pivotal role for aromatic residues in peptide-mediated endotoxin neutralization by CATH-2 analogs and were shown to be independent of LPS affinity. The capacity to modulate chemokine production and dampen endotoxin-induced pro-inflammatory responses in chicken immune cells implicates that small CATH-2 based peptides could serve as leads for the design of CATH-2 based immunomodulatory anti-infectives.

Using Microelectrode Arrays for Neurotoxicity Screening

EPA Science Inventory

Chemicals can disrupt nervous system electrical activity, rapidly causing toxicity prior to, or in the absence of, biochemical or morphological changes. However, high-throughput, functional approaches to detect chemical induced changes in electrical excitability are lacking. Micr...

Fish can show emotional fever: stress-induced hyperthermia in zebrafish.

PubMed

Rey, Sonia; Huntingford, Felicity A; Boltaña, Sebastian; Vargas, Reynaldo; Knowles, Toby G; Mackenzie, Simon

2015-11-22

Whether fishes are sentient beings remains an unresolved and controversial question. Among characteristics thought to reflect a low level of sentience in fishes is an inability to show stress-induced hyperthermia (SIH), a transient rise in body temperature shown in response to a variety of stressors. This is a real fever response, so is often referred to as 'emotional fever'. It has been suggested that the capacity for emotional fever evolved only in amniotes (mammals, birds and reptiles), in association with the evolution of consciousness in these groups. According to this view, lack of emotional fever in fishes reflects a lack of consciousness. We report here on a study in which six zebrafish groups with access to a temperature gradient were either left as undisturbed controls or subjected to a short period of confinement. The results were striking: compared to controls, stressed zebrafish spent significantly more time at higher temperatures, achieving an estimated rise in body temperature of about 2-4°C. Thus, zebrafish clearly have the capacity to show emotional fever. While the link between emotion and consciousness is still debated, this finding removes a key argument for lack of consciousness in fishes. © 2015 The Authors.

Fish can show emotional fever: stress-induced hyperthermia in zebrafish

PubMed Central

Huntingford, Felicity A.; Boltaña, Sebastian; Vargas, Reynaldo; Knowles, Toby G.; Mackenzie, Simon

2015-01-01

Whether fishes are sentient beings remains an unresolved and controversial question. Among characteristics thought to reflect a low level of sentience in fishes is an inability to show stress-induced hyperthermia (SIH), a transient rise in body temperature shown in response to a variety of stressors. This is a real fever response, so is often referred to as ‘emotional fever’. It has been suggested that the capacity for emotional fever evolved only in amniotes (mammals, birds and reptiles), in association with the evolution of consciousness in these groups. According to this view, lack of emotional fever in fishes reflects a lack of consciousness. We report here on a study in which six zebrafish groups with access to a temperature gradient were either left as undisturbed controls or subjected to a short period of confinement. The results were striking: compared to controls, stressed zebrafish spent significantly more time at higher temperatures, achieving an estimated rise in body temperature of about 2–4°C. Thus, zebrafish clearly have the capacity to show emotional fever. While the link between emotion and consciousness is still debated, this finding removes a key argument for lack of consciousness in fishes. PMID:26609087

Alteration of functional state of peripheral blood erythrocytes in women of different age groups at dislipidemia conditions.

PubMed

Ratiani, L; Intskirveli, N; Ormotsadze, G; Sanikidze, T

2011-12-01

The aim of the study was identification of statistically reliable correlations and the cause-effect relationships between viability of red blood cells and dislipidema parametres and/or metabolic disorders, induced by age related alterations of estrogen content, in women of different ages (reproductive, menopausal) On the basis of the analysis of research results we can conclude that in the different age groups of women with atherosclerosis-induced cardiovascular diseases revealed estrogen-related dependence between Tg-s and HDL content, functional status of phereperial blood erytrotcites and severity of dislipidemia. The aterogenic index Tg/HD proved to be sensitive marker of dislipidemia in reproductive aging women, but does't reflect disorders of lipid metabolism in postmenosal women. It was proved the existence of reliable corelation between red blood cells dysfunction indicator, spherulation quality, and atherogenic index Tg/HDL highlights; however, the correlation coefficient is 2 times higher in the reproductive age as in menopause. Spherulation quality of red blood cells at low HDL content showd fast growth rate in reproductive-aged women, and was unsensetive to HDL content in postmenopasal women. It was concluded that age-related lack of estrogens in postmenopausal women indirectly contributes to decrease protection of red blood cells against oxidative damage, reduces their deformabelity and disturbances the rheological properties. So, Spherulation quality of red blood cells may be used as a diagnostic marker of severity of atherosclerosis.

Neural and Hemodynamic Responses Elicited by Forelimb- and Photo-stimulation in Channelrhodopsin-2 Mice: Insights into the Hemodynamic Point Spread Function

PubMed Central

Vazquez, Alberto L.; Fukuda, Mitsuhiro; Crowley, Justin C.; Kim, Seong-Gi

2014-01-01

Hemodynamic responses are commonly used to map brain activity; however, their spatial limits have remained unclear because of the lack of a well-defined and malleable spatial stimulus. To examine the properties of neural activity and hemodynamic responses, multiunit activity, local field potential, cerebral blood volume (CBV)-sensitive optical imaging, and laser Doppler flowmetry were measured from the somatosensory cortex of transgenic mice expressing Channelrhodopsin-2 in cortex Layer 5 pyramidal neurons. The magnitude and extent of neural and hemodynamic responses were modulated using different photo-stimulation parameters and compared with those induced by somatosensory stimulation. Photo-stimulation-evoked spiking activity across cortical layers was similar to forelimb stimulation, although their activity originated in different layers. Hemodynamic responses induced by forelimb- and photo-stimulation were similar in magnitude and shape, although the former were slightly larger in amplitude and wider in extent. Altogether, the neurovascular relationship differed between these 2 stimulation pathways, but photo-stimulation-evoked changes in neural and hemodynamic activities were linearly correlated. Hemodynamic point spread functions were estimated from the photo-stimulation data and its full-width at half-maximum ranged between 103 and 175 µm. Therefore, submillimeter functional structures separated by a few hundred micrometers may be resolved using hemodynamic methods, such as optical imaging and functional magnetic resonance imaging. PMID:23761666

Dominance relationships in Syrian hamsters modulate neuroendocrine and behavioral responses to social stress.

PubMed

Dulka, Brooke N; Koul-Tiwari, Richa; Grizzell, J Alex; Harvey, Marquinta L; Datta, Subimal; Cooper, Matthew A

2018-06-22

Stress is a well-known risk factor for psychopathology and rodent models of social defeat have strong face, etiological, construct and predictive validity for these conditions. Syrian hamsters are highly aggressive and territorial, but after an acute social defeat experience they become submissive and no longer defend their home territory, even from a smaller, non-aggressive intruder. This defeat-induced change in social behavior is called conditioned defeat (CD). We have shown that dominant hamsters show increased neural activity in the ventromedial prefrontal cortex (vmPFC) following social defeat stress and exhibit a reduced CD response at social interaction testing compared to subordinates. Although the vmPFC can inhibit the neuroendocrine stress response, it is unknown whether dominants and subordinates differ in stress-induced activity of the extended hypothalamic-pituitary-adrenal (HPA) axis. Here, we show that, following acute social defeat, dominants exhibit decreased submissive and defensive behavior compared to subordinates but do not differ from subordinates or social status controls (SSCs) in defeat-induced cortisol concentrations. Furthermore, both dominants and SSCs show greater corticotropin-releasing hormone (CRH) mRNA expression in the basolateral/central amygdala compared to subordinates, while there was no effect of social status on CRH mRNA expression in the paraventricular nucleus of the hypothalamus or bed nucleus of the stria terminalis. Overall, status-dependent differences in the CD response do not appear linked to changes in stress-induced cortisol concentrations or CRH gene expression, which is consistent with the view that stress resilience is not a lack of a physiological stress response but the addition of stress coping mechanisms. Lay summary Dominant hamsters show resistance to the behavioral effects of acute social defeat compared to subordinates, but it is unclear whether social status modulates the neuroendocrine stress response in Syrian hamsters. This study indicates that dominant social status does not alter stress-induced activity of the extended hypothalamic-pituitary-adrenal (HPA) axis, which suggests that the ability of dominants to cope with social defeat stress is not associated with changes in their neuroendocrine stress response.

Standardization of a model to study revaccination against Marek's disease under laboratory conditions.

PubMed

Gimeno, Isabel M; Witter, Richard L; Cortes, Aneg L; Reddy, Sanjay M; Pandiri, Arun R

2012-01-01

Revaccination, the practice of administering Marek's disease (MD) vaccine a second time, has been used in commercial poultry flocks for many years. The rationale is largely anecdotal as the few published reports have failed to provide support for the value of the practice. In the present work, we have standardized a model to study MD revaccination under laboratory conditions. Nine bird experiments were conducted to evaluate homologous revaccination (same vaccine administered twice) and heterologous revaccination (administration of two different vaccines) with various challenge models. Our results demonstrated that heterologous revaccination (with a second vaccine more protective than the first vaccine) but not homologous revaccination provided a beneficial increase in protection. Administration of the first vaccine at 18 days of embryonation followed by a more protective second vaccine at hatch reproduced systematically the benefits of revaccination. In addition, our results show that revaccination protocols might aid in solving major drawbacks associated with various highly protective experimental MD vaccines; that is, lymphoid organ atrophy and residual virulence. Strain RM1 is one of the most protective vaccines against early challenge with highly virulent MD virus but it induces severe lymphoid atrophy in chickens lacking maternal antibodies against MD virus. In this study, strain RM1 did not induce lymphoid organ atrophy when administered as second vaccine in a revaccination protocol. Similarly, strain 648A100/BP5 maintains residual virulence in chickens lacking maternal antibodies against MD virus but did not induce any lesions when used as a second vaccine. Until now, arbitrary revaccination protocols have been occasionally proven useful to the poultry industry. The model developed in this study will allow for a better understanding of this phenomenon and its optimization. A more rational use of this practice will be of great help to control MD outbreaks until better vaccines are available.

Action of nitrofurans on E. coli: mutation and induction and repair of daughter-strand gaps in DNA.

PubMed

Lu, C; McCalla, D R; Bryant, D W

1979-06-01

The antibacterial and mutagenic potency of 9 nitrofurans in "treat and plate" experiments varied over almost 5 orders of magnitude. The relative toxicities were as follows: FANFT greater than AF2 greater than ANFT greather than furazolidone greater than furagin greater than nitrofurantoin greater than nitrofurazone greater than methylnitrofuroate greater than nitrofuroic acid. In general, mutagenic activity paralleled toxicity. The compounds at concentrations corresponding to their LD50's, induced mutations at frequencies which ranged from 2.5/10(6) survivors for FANFT to 130/10(6) survivors for furagin (NF416). The observed differences in antibacterial and mutagenic activity are unlikely to be due to lack of activation of the weaker agents since the two most potent agents were reduced somewhat more slowly than many of the less active agents. The relative sensitivities to the antibacterial effects of AF2 of strains WP2, WP2 uvrA, CM561 (lexA) and CM571 (recA) were 1 : 1.6 : 3 : 7 and to nitrofurazone 1 : 1 : 25 : 50. The wvrA strain was 6--7-fold more mutable with both these agents than was WP2. No increase over the spontaneous mutation frequency was observed when recA or lexA strains were exposed to either AF2 or nitrofurazone in these experiments. When wild-type of wvrA bacteria containing nitrofuran-induced lesions replicated their DNA in drug-free medium in the presence of [3H]thymidine for 5 min, the label was found in low molecular weight DNA indicating that daughter-strand gaps were formed. During subsequent incubation in nonradioactive medium the molecular weight of the DNA increased to the control value. A recA strain (which was very sensitive to the lethal effects of AF2 and nitrofurazone) lacked the ability to repair daughter-strand gaps caused by nitrofuran-induced lesions.

Distance Mapping in Proteins Using Fluorescence Spectroscopy: The Tryptophan-Induced Quenching (TrIQ) Method

PubMed Central

Mansoor, Steven E.; DeWitt, Mark A.; Farrens, David L.

2014-01-01

Studying the interplay between protein structure and function remains a daunting task. Especially lacking are methods for measuring structural changes in real time. Here we report our most recent improvements to a method that can be used to address such questions. This method, which we now call Tryptophan induced quenching (TrIQ), provides a straightforward, sensitive and inexpensive way to address questions of conformational dynamics and short-range protein interactions. Importantly, TrIQ only occurs over relatively short distances (~5 to 15 Å), making it complementary to traditional fluorescence resonance energy transfer (FRET) methods that occur over distances too large for precise studies of protein structure. As implied in the name, TrIQ measures the efficient quenching induced in some fluorophores by tryptophan (Trp). We present here our analysis of the TrIQ effect for five different fluorophores that span a range of sizes and spectral properties. Each probe was attached to four different cysteine residues on T4 lysozyme and the extent of TrIQ caused by a nearby Trp was measured. Our results show that for smaller probes, TrIQ is distance dependent. Moreover, we also demonstrate how TrIQ data can be analyzed to determine the fraction of fluorophores involved in a static, non-fluorescent complex with Trp. Based on this analysis, our study shows that each fluorophore has a different TrIQ profile, or "sphere of quenching", which correlates with its size, rotational flexibility, and the length of attachment linker. This TrIQ-based "sphere of quenching" is unique to every Trp-probe pair and reflects the distance within which one can expect to see the TrIQ effect. It provides a straightforward, readily accessible approach for mapping distances within proteins and monitoring conformational changes using fluorescence spectroscopy. PMID:20886836

Above-Ground Dimensions and Acclimation Explain Variation in Drought Mortality of Scots Pine Seedlings from Various Provenances

PubMed Central

Seidel, Hannes; Menzel, Annette

2016-01-01

Seedling establishment is a critical part of the life cycle, thus seedling survival might be even more important for forest persistence under recent and future climate change. Scots pine forests have been disproportionally more affected by climate change triggered forest-dieback. Nevertheless, some Scots pine provenances might prove resilient to future drought events because of the species’ large distributional range, genetic diversity, and adaptation potential. However, there is a lack of knowledge on provenance-specific survival under severe drought events and on how acclimation alters survival rates in Scots pine seedlings. We therefore conducted two drought-induced mortality experiments with potted Scots pine seedlings in a greenhouse. In the first experiment, 760 three-year-old seedlings from 12 different provenances of the south-western distribution range were subjected to the same treatment followed by the mortality experiment in 2014. In the second experiment, we addressed the question of whether acclimation to re-occurring drought stress events and to elevated temperature might decrease mortality rates. Thus, 139 four-year-old seedlings from France, Germany, and Poland were subjected to different temperature regimes (2012–2014) and drought treatments (2013–2014) before the mortality experiment in 2015. Provenances clearly differed in their hazard of drought-induced mortality, which was only partly related to the climate of their origin. Drought acclimation decreased the hazard of drought-induced mortality. Above-ground dry weight and height were the main determinants for the hazard of mortality, i.e., heavier and taller seedlings were more prone to mortality. Consequently, Scots pine seedlings exhibit a considerable provenance-specific acclimation potential against drought mortality and the selection of suitable provenances might thus facilitate seedling establishment and the persistence of Scots pine forest. PMID:27458477

Persistence of Space Radiation Induced Cytogenetic Damage in the Blood Lymphocytes of Astronauts

NASA Technical Reports Server (NTRS)

George, Kerry; Cucinotta, Francis A.

2008-01-01

Cytogenetic damage in astronaut's peripheral blood lymphocytes is a useful in vivo marker of space radiation induced damage. Moreover, if radiation induced chromosome translocations persist in peripheral blood lymphocytes for many years, as has been assumed, they could potentially be used to measure retrospective doses or prolonged low dose rate exposures. However, as more data becomes available, evidence suggests that the yield of translocations may decline with time after exposure, at least in the case of space radiation exposures. We present our latest follow-up measurements of chromosome aberrations in astronauts blood lymphocytes assessed by FISH painting and collected a various times beginning directly after return from space to several years after flight. For most individuals the analysis of individual time-courses for translocations revealed a temporal decline of yields with different half-lives. Since the level of stable aberrations depends on the interplay between natural loss of circulating T-lymphocytes and replenishment from the stem or progenitor cells, the differences in the rates of decay could be explained by inter-individual variation in lymphocyte turn over. Biodosimetry estimates derived from cytogenetic analysis of samples collected a few days after return to earth lie within the range expected from physical dosimetry. However, a temporal decline in yields may indicate complications with the use of stable aberrations for retrospective dose reconstruction, and the differences in the decay time may reflect individual variability in risk from space radiation exposure. In addition, limited data on multiple flights show a lack of correlation between time in space and translocation yields. Data from one crewmember who has participated in two separate long-duration space missions and has been followed up for over 10 years provides limited information on the effect of repeat flights and show a possible adaptive response to space radiation exposure.

Eosinophils release extracellular DNA traps in response to Aspergillus fumigatus.

PubMed

Muniz, Valdirene S; Silva, Juliana C; Braga, Yasmim A V; Melo, Rossana C N; Ueki, Shigeharu; Takeda, Masahide; Hebisawa, Akira; Asano, Koichiro; Figueiredo, Rodrigo T; Neves, Josiane S

2018-02-01

Eosinophils mediate the immune response in different infectious conditions. The release of extracellular DNA traps (ETs) by leukocytes has been described as an innate immune response mechanism that is relevant in many disorders including fungal diseases. Different stimuli induce the release of human eosinophil ETs (EETs). Aspergillus fumigatus is an opportunistic fungus that may cause eosinophilic allergic bronchopulmonary aspergillosis (ABPA). It has been reported that eosinophils are important to the clearance of A fumigatus in infected mice lungs. However, the immunological mechanisms that underlie the molecular interactions between A fumigatus and eosinophils are poorly understood. Here, we investigated the presence of EETs in the bronchial mucus plugs of patients with ABPA. We also determined whether A fumigatus induced the release of human eosinophil EETs in vitro. Mucus samples of patients with ABPA were analyzed by light and confocal fluorescence microscopy. The release of EETs by human blood eosinophils was evaluated using different pharmacological tools and neutralizing antibodies by fluorescence microscopy and a fluorimetric method. We identified abundant nuclear histone-bearing EETs in the bronchial secretions obtained from patients with ABPA. In vitro, we demonstrated that A fumigatus induces the release of EETs through a mechanism independent of reactive oxygen species but associated with eosinophil death, histone citrullination, CD11b, and the Syk tyrosine kinase pathway. EETs lack the killing or fungistatic activities against A fumigatus. Our findings may contribute to the understanding of how eosinophils recognize and act as immune cells in response to A fumigatus, which may lead to novel insights regarding the treatment of patients with ABPA. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Heavy Metals Induce Iron Deficiency Responses at Different Hierarchic and Regulatory Levels.

PubMed

Lešková, Alexandra; Giehl, Ricardo F H; Hartmann, Anja; Fargašová, Agáta; von Wirén, Nicolaus

2017-07-01

In plants, the excess of several heavy metals mimics iron (Fe) deficiency-induced chlorosis, indicating a disturbance in Fe homeostasis. To examine the level at which heavy metals interfere with Fe deficiency responses, we carried out an in-depth characterization of Fe-related physiological, regulatory, and morphological responses in Arabidopsis ( Arabidopsis thaliana ) exposed to heavy metals. Enhanced zinc (Zn) uptake closely mimicked Fe deficiency by leading to low chlorophyll but high ferric-chelate reductase activity and coumarin release. These responses were not caused by Zn-inhibited Fe uptake via IRON-REGULATED TRANSPORTER (IRT1). Instead, Zn simulated the transcriptional response of typical Fe-regulated genes, indicating that Zn affects Fe homeostasis at the level of Fe sensing. Excess supplies of cobalt and nickel altered root traits in a different way from Fe deficiency, inducing only transient Fe deficiency responses, which were characterized by a lack of induction of the ethylene pathway. Cadmium showed a rather inconsistent influence on Fe deficiency responses at multiple levels. By contrast, manganese evoked weak Fe deficiency responses in wild-type plants but strongly exacerbated chlorosis in irt1 plants, indicating that manganese antagonized Fe mainly at the level of transport. These results show that the investigated heavy metals modulate Fe deficiency responses at different hierarchic and regulatory levels and that the interaction of metals with physiological and morphological Fe deficiency responses is uncoupled. Thus, this study not only emphasizes the importance of assessing heavy metal toxicities at multiple levels but also provides a new perspective on how Fe deficiency contributes to the toxic action of individual heavy metals. © 2017 American Society of Plant Biologists. All Rights Reserved.

Healing Effect of Pistacia Atlantica Fruit Oil Extract in Acetic Acid-Induced Colitis in Rats

PubMed Central

Tanideh, Nader; Masoumi, Samira; Hosseinzadeh, Massood; Safarpour, Ali Reza; Erjaee, Hoda; Koohi-Hosseinabadi, Omid; Rahimikazerooni, Salar

2014-01-01

Background: Considering the anti-oxidant properties of Pistacia atlantica and lack of data regarding its efficacy in the treatment of ulcerative colitis, this study aims at investigating the effect of the Pistacia atlantica fruit extract in treating experimentally induced colitis in a rat model. Methods: Seventy male Sprague-Dawley rats (weighing 220±20 g) were used. All rats fasted 24 hours before the experimental procedure. The rats were randomly divided into 7 groups, each containing 10 induced colitis with 2ml acetic acid (3%). Group 1 (Asacol), group 2 (base gel) and group 7 (without treatment) were assigned as control groups. Group 3 (300 mg/ml) and group 4 (600 mg/ml) received Pistacia atlantica fruit orally. Group 5 (10% gel) and group 6 (20% gel) received Pistacia atlantica in the form of gel as enema. Macroscopic, histopathological examination and MDA measurement were carried out. Results: All groups revealed significant macroscopic healing in comparison with group 7 (P<0.001). Regarding microscopic findings in the treatment groups compared with group 7, the latter group differed significantly with groups 1, 2, 4 and 6 (P<0.001). There was a significant statistical difference in MDA scores of the seven treatment groups (F(5,54)=76.61, P<0.001). Post-hoc comparisons indicated that the mean±SD score of Asacol treated group (1.57±0.045) was not significantly different from groups 4 (1.62±0.024) and 6 (1.58±0.028). Conclusion: Our study showed that a high dose of Pistacia atlantica fruit oil extract, administered orally and rectally can improve colitis physiologically and pathologically in a rat model, and may be efficient for ulcerative colitis. PMID:25429174

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

Malouli, Daniel; Hansen, Scott G.; Nakayasu, Ernesto S.

The tegument phosphoprotein pp65 (UL83) is the most abundant virion protein in human cytomegalovirus (HCMV). Since pp65 is immunodominant in persistently infected individuals, subunit vaccines against HCMV often include pp65 as T cell stimulatory component. Although HCMV pp65 is non-essential for viral growth in vitro it is thought to have an important role in primary and persistent infection since pp65 displays multiple immunomodulatory functions. To determine whether pp65 is required for infection and to evaluate its role in natural and vaccination-induced immunity we generated a rhesus CMV lacking both homologues, pp65a (Rh111) and pp65b (Rh112). Lack of pp65 resulted inmore » a slight growth defect in vitro and an increase of defective particle formation. However, most pp65-deleted virions in the supernatant were phenotypically normal and proteomics analysis revealed that the ratios of the remaining viral proteins were largely unchanged. RhCMV Δpp65ab was able to persistently infect CMV-negative rhesus macaques (RM) and to super-infect RM previously infected with CMV. To determine whether T cells against pp65 are essential for protection against CMV, we challenged Δpp65ab-infected animals with RhCMV ΔUS2-11, a viral recombinant that lacks inhibitors of MHC-I antigen presentation and is thus unable to overcome CMV-specific T cell immunity. Despite a complete lack of pp65-specific T cells, Δpp65ab protected against ΔUS2-11 challenge suggesting that pp65-specific T cells are not essential for T cell immunity against CMV. Using the same approach we further demonstrate that pp65b-specific T cells, induced by heterologous prime/boost vaccination, are not sufficient to protect against ΔUS2-11 challenge. Our data provides a new approach to test the efficacy of subunit vaccine candidates and suggest that pp65 vaccines are insufficient to induce a T cell response that recapitulates the protective effect of natural infection.« less

Conventional and high-dose daunorubicin and idarubicin in acute myeloid leukaemia remission induction treatment: a mixed treatment comparison meta-analysis of 7258 patients.

PubMed

Sekine, Leo; Morais, Vinícius Daudt; Lima, Karine Margarites; Onsten, Tor Gunnar Hugo; Ziegelmann, Patrícia Klarmann; Ribeiro, Rodrigo Antonini

2015-12-01

Previous meta-analyses suggested that acute myeloid leukaemia induction regimens containing idarubicin (IDA) or high-dose daunorubicin (HDD) induce higher rates of complete remission (CR) than conventional-dose daunorubicin (CDD), with a possible benefit in overall survival. However, robust comparisons between these regimens are still lacking. We conducted a mixed treatment comparison meta-analysis regarding these three regimens. Mixed treatment comparison is a statistical method of data summarization that aggregates data from both direct and indirect effect estimates. Literature search strategy included MEDLINE, EMBASE, Cochrane, Scielo and LILACS, from inception until August 2013 and resulted in the inclusion of 17 trials enrolling 7258 adult patients. HDD [relative risk (RR) 1.13; 95% credible interval (CrI) 1.02-1.26] and IDA (RR 1.13; 95% CrI 1.05-1.23) showed higher CR rates than CDD. IDA also led to lower long-term overall mortality rates when compared with CDD (RR 0.93, 95% CrI 0.86-0.99), whereas HDD and CDD were no different (RR 0.94, 95% CrI 0.85-1.02). HDD and IDA comparison did not reach statistically significant differences in CR (RR 1.00; 95% CrI 0.89-1.11) and in long-term mortality (RR 1.01, 95% CrI 0.91-1.11). IDA and HDD are consistently superior to CDD in inducing CR, and IDA was associated with lower long-term mortality. On the basis of these findings, we recommend incorporation of IDA and HDD instead of the traditional CDD as standard treatments for acute myeloid leukaemia induction. The lack of HDD benefit on mortality, when compared with CDD in this study, should be cautiously addressed, because it may have been susceptible to underestimation because of statistical power limitations. Copyright © 2014 John Wiley & Sons, Ltd.

Analysis of Terminal Deletions using a Generalized Time-Dependent Model of Radiation-Induced Formation of Chromosomal Aberrations

NASA Technical Reports Server (NTRS)

Ponomarev, Artem L.; George, K.; Cucinotta, Francis A.

2011-01-01

We have developed a model that can simulate different types of radiation induced chromosomal aberrations (CA's) and can provide predictions on the frequency and size of chromosomes with terminal deletions. Chromosomes with terminal deletions lack telomeres and this can elicit sister chromatid unions and the prolonged breakage/fusion/bridge (B/F/B) cycles that have been observed in mammalian tumors. The loss of a single telomere has been shown to cause extensive genomic instability through the B/F/B cycle process. Our model uses a stochastic process of DNA broken end joining, in which a realistic spectrum of CA's is created from improperly joined DNA free ends formed by DNA double strand breaks (DSBs). The distribution of the DNA free ends is given by a mechanistic model that takes into account the chromatin structure and track structure for high-LET radiation. The model allows for DSB clustering from high-LET radiation and simulates the formation of CA's in stages that correspond to the actual time after radiation exposure. The time scale for CA formation is derived from experimental data on DSB repair kinetics. At any given time a nucleus may have intact chromosomes, CA's, and/or unrepaired fragments, some of which are defined as terminal deletions, if they are capped by one telomere. The model produces a spectrum of terminal deletions with their corresponding probabilities and size distributions for different heavy ions exposures for the first division after exposure. This data provides valuable information because there is limited experimental data available in the literature on the on the actual size of terminal deletions. We compare our model output to the available experimental data and make a reasonable extrapolation on the number of chromosomes lacking telomeres in human lymphocytes exposed to heavy ions. This model generates data which may lead to predictions on the rate of genomic instability in cells after exposure to high charge and energy nuclei affecting astronauts during space missions.

The urgent need for quality improvement in Russia.

PubMed

Ruevekamp, D

1994-01-01

Induced abortion became accepted as a legal method of family planning after the October Revolution of 1917 from which terminations were performed in state hospitals free of charge upon a woman's request. The procedure was made legal in response to then newly voiced egalitarian ideals and the increasing involvement of women in the labor market, as well as because of the rapidly deteriorating situation and post-Revolution period of famine. Administrators fully expected to reduce the incidence of abortion once living conditions improved. Little was done at the time to develop contraceptives. Stalin, however, in the 1920s and 1930s, lamented a falling birth rate in the face of manpower needed for labor and the military; abortion and contraceptives were banned, leading to post-abortion complications without really stimulating the birth rate. Abortion was relegalized in 1956, but the right to contraception was never fully restored. Seven million induced abortions were officially registered to have taken place in each of the last ten years in the former Soviet Union. A woman typically undergoes one abortion per year, or approximately twenty abortions during the childbearing period of her life. Lacking knowledge about contraception, contraceptives, and what many Western countries regard to be women's reproductive health rights, most Russian women, however, freely tolerate frequent repeated abortion as a normal method of fertility regulation. Lack of access to contraceptives along with the lack of domestic contraceptive method production facilities and lack of hard currency to secure quality supplies from abroad are contributing factors to this ongoing trend. Gynecologists also receive lucrative fees for illegal abortions and are unlikely to promote change. Plans to open twelve family planning centers in Moscow have been hampered by the inertia of bureaucracy, the lack of financial means, the lack of trained personnel, and people's suspicion of government bodies. Much needs to be done in Russia about family planning, including involving men in matters of sexual behavior and birth control.

Magnetic properties of the upper mantle beneath the continental United States

NASA Astrophysics Data System (ADS)

Friedman, S. A.; Ferre, E. C.; Demory, F.; Rochette, P.; Martin Hernandez, F.; Conder, J. A.

2012-12-01

The interpretation of long wavelength satellite magnetic data (Magsat, Oersted, CHAMP, SWARM) requires an understanding of magnetic mineralogy in the lithospheric mantle and reliable models of induced and remanent magnetic sources in the lithospheric mantle and the crust. Blakely et al. (2005) proposed the hypothesis of a magnetic lithospheric mantle in subduction zones. This prompted us to reexamine magnetic sources in the lithospheric mantle in different tectonic settings where unaltered mantle xenolith have been reported since the 1990s. Xenoliths from the upper mantle beneath the continental United States show different magnetic properties depending on the tectonic setting in which they equilibrated. Three localities in the South Central United States (San Carlos, AZ; Kilbourne Hole, NM; Knippa, TX) produced lherzolite and harzburgite xenoliths, while the Bearpaw Mountains in Montana (subduction zone) produced dunite and phlogopite-rich dunite xenoliths. Paleomagnetic data on these samples shows the lack of secondary alteration which is commonly caused by post-eruption serpentinization and the lack of basalt contamination. The main magnetic carrier is pure magnetite. The ascent of mantle xenoliths to the surface of the Earth generally takes only a few hours. Numerical modelling shows that nucleation of magnetite during ascent would form superparamagnetic grains and therefore cannot explain the observed magnetic grain sizes. This implies that the ferromagnetic phases present in the studied samples formed at mantle depth. The samples from the South Central United States exhibit a small range in low-field magnetic susceptibility (+/- 0.00003 [SI]), and Natural Remanent Magnetization (NRM) between 0.001 - 0.100 A/m. To the contrary samples from the Bearpaw Mountains exhibit a wider range of low-field susceptibilities (0.00001 to 0.0015 [SI]) and NRM (0.01 and 9.00 A/m). These samples have been serpentinized in-situ by metasomatic fluids related to the Farallon plate (Facer et al., 2009). Hence, the magnetic properties of the lithospheric mantle beneath the continental United States differ significantly depending on tectonic setting. The combination of the low geotherm observed in the Bearpaw Mountains with the stronger induced and remanent magnetization of mantle rocks in this area may produce a detectable LWMA.

Involvement of all-trans-retinal in acute light-induced retinopathy of mice.

PubMed

Maeda, Akiko; Maeda, Tadao; Golczak, Marcin; Chou, Steven; Desai, Amar; Hoppel, Charles L; Matsuyama, Shigemi; Palczewski, Krzysztof

2009-05-29

Exposure to bright light can cause visual dysfunction and retinal photoreceptor damage in humans and experimental animals, but the mechanism(s) remain unclear. We investigated whether the retinoid cycle (i.e. the series of biochemical reactions required for vision through continuous generation of 11-cis-retinal and clearance of all-trans-retinal, respectively) might be involved. Previously, we reported that mice lacking two enzymes responsible for clearing all-trans-retinal, namely photoreceptor-specific ABCA4 (ATP-binding cassette transporter 4) and RDH8 (retinol dehydrogenase 8), manifested retinal abnormalities exacerbated by light and associated with accumulation of diretinoid-pyridinium-ethanolamine (A2E), a condensation product of all-trans-retinal and a surrogate marker for toxic retinoids. Now we show that these mice develop an acute, light-induced retinopathy. However, cross-breeding these animals with lecithin:retinol acyltransferase knock-out mice lacking retinoids within the eye produced progeny that did not exhibit such light-induced retinopathy until gavaged with the artificial chromophore, 9-cis-retinal. No significant ocular accumulation of A2E occurred under these conditions. These results indicate that this acute light-induced retinopathy requires the presence of free all-trans-retinal and not, as generally believed, A2E or other retinoid condensation products. Evidence is presented that the mechanism of toxicity may include plasma membrane permeability and mitochondrial poisoning that lead to caspase activation and mitochondria-associated cell death. These findings further understanding of the mechanisms involved in light-induced retinal degeneration.

Few effects of invasive plants Reynoutria japonica, Rudbeckia laciniata and Solidago gigantea on soil physical and chemical properties.

PubMed

Stefanowicz, Anna M; Stanek, Małgorzata; Nobis, Marcin; Zubek, Szymon

2017-01-01

Biological invasions are an important problem of human-induced changes at a global scale. Invasive plants can modify soil nutrient pools and element cycling, creating feedbacks that potentially stabilize current or accelerate further invasion, and prevent re-establishment of native species. The aim of this study was to compare the effects of Reynoutria japonica, Rudbeckia laciniata and Solidago gigantea, invading non-forest areas located within or outside river valleys, on soil physical and chemical parameters, including soil moisture, element concentrations, organic matter content and pH. Additionally, invasion effects on plant species number and total plant cover were assessed. The concentrations of elements in shoots and roots of invasive and native plants were also measured. Split-plot ANOVA revealed that the invasions significantly reduced plant species number, but did not affect most soil physical and chemical properties. The invasions decreased total P concentration and increased N-NO 3 concentration in soil in comparison to native vegetation, though the latter only in the case of R. japonica. The influence of invasion on soil properties did not depend on location (within- or outside valleys). The lack of invasion effects on most soil properties does not necessarily imply the lack of influence of invasive plants, but may suggest that the direction of the changes varies among replicate sites and there are no general patterns of invasion-induced alterations for these parameters. Tissue element concentrations, with the exception of Mg, did not differ between invasive and native plants, and were not related to soil element concentrations. Copyright © 2016 Elsevier B.V. All rights reserved.

Distinctive Expansion of Potential Virulence Genes in the Genome of the Oomycete Fish Pathogen Saprolegnia parasitica

PubMed Central

Belmonte, Rodrigo; Löbach, Lars; Christie, James; van den Ackerveken, Guido; Bottin, Arnaud; Bulone, Vincent; Díaz-Moreno, Sara M.; Dumas, Bernard; Fan, Lin; Gaulin, Elodie; Govers, Francine; Grenville-Briggs, Laura J.; Horner, Neil R.; Levin, Joshua Z.; Mammella, Marco; Meijer, Harold J. G.; Morris, Paul; Nusbaum, Chad; Oome, Stan; Phillips, Andrew J.; van Rooyen, David; Rzeszutek, Elzbieta; Saraiva, Marcia; Secombes, Chris J.; Seidl, Michael F.; Snel, Berend; Stassen, Joost H. M.; Sykes, Sean; Tripathy, Sucheta; van den Berg, Herbert; Vega-Arreguin, Julio C.; Wawra, Stephan; Young, Sarah K.; Zeng, Qiandong; Dieguez-Uribeondo, Javier; Russ, Carsten; Tyler, Brett M.; van West, Pieter

2013-01-01

Oomycetes in the class Saprolegniomycetidae of the Eukaryotic kingdom Stramenopila have evolved as severe pathogens of amphibians, crustaceans, fish and insects, resulting in major losses in aquaculture and damage to aquatic ecosystems. We have sequenced the 63 Mb genome of the fresh water fish pathogen, Saprolegnia parasitica. Approximately 1/3 of the assembled genome exhibits loss of heterozygosity, indicating an efficient mechanism for revealing new variation. Comparison of S. parasitica with plant pathogenic oomycetes suggests that during evolution the host cellular environment has driven distinct patterns of gene expansion and loss in the genomes of plant and animal pathogens. S. parasitica possesses one of the largest repertoires of proteases (270) among eukaryotes that are deployed in waves at different points during infection as determined from RNA-Seq data. In contrast, despite being capable of living saprotrophically, parasitism has led to loss of inorganic nitrogen and sulfur assimilation pathways, strikingly similar to losses in obligate plant pathogenic oomycetes and fungi. The large gene families that are hallmarks of plant pathogenic oomycetes such as Phytophthora appear to be lacking in S. parasitica, including those encoding RXLR effectors, Crinkler's, and Necrosis Inducing-Like Proteins (NLP). S. parasitica also has a very large kinome of 543 kinases, 10% of which is induced upon infection. Moreover, S. parasitica encodes several genes typical of animals or animal-pathogens and lacking from other oomycetes, including disintegrins and galactose-binding lectins, whose expression and evolutionary origins implicate horizontal gene transfer in the evolution of animal pathogenesis in S. parasitica. PMID:23785293

Non-canonical Activities of Hog1 Control Sensitivity of Candida albicans to Killer Toxins From Debaryomyces hansenii

PubMed Central

Morales-Menchén, Ana; Navarro-García, Federico; Guirao-Abad, José P.; Román, Elvira; Prieto, Daniel; Coman, Ioana V.; Pla, Jesús; Alonso-Monge, Rebeca

2018-01-01

Certain yeasts secrete peptides known as killer toxins or mycocins with a deleterious effect on sensitive yeasts or filamentous fungi, a common phenomenon in environmental species. In a recent work, different Debaryomyces hansenii (Dh) strains isolated from a wide variety of cheeses were identified as producing killer toxins active against Candida albicans and Candida tropicalis. We have analyzed the killer activity of these toxins in C. albicans mutants defective in MAPK signaling pathways and found that the lack of the MAPK Hog1 (but not Cek1 or Mkc1) renders cells hypersensitive to Dh mycocins while mutants lacking other upstream elements of the pathway behave as the wild type strain. Point mutations in the phosphorylation site (T174A-176F) or in the kinase domain (K52R) of HOG1 gene showed that both activities were relevant for the survival of C. albicans to Dh killer toxins. Moreover, Hog1 phosphorylation was also required to sense and adapt to osmotic and oxidative stress while the kinase activity was somehow dispensable. Although the addition of supernatant from the killer toxin- producing D. hansenii 242 strain (Dh-242) induced a slight intracellular increase in Reactive Oxygen Species (ROS), overexpression of cytosolic catalase did not protect C. albicans against this mycocin. This supernatant induced an increase in intracellular glycerol concentration suggesting that this toxin triggers an osmotic stress. We also provide evidence of a correlation between sensitivity to Dh-242 killer toxin and resistance to Congo red, suggesting cell wall specific alterations in sensitive strains. PMID:29774204

Dead or Alive? Using Membrane Failure and Chlorophyll a Fluorescence to Predict Plant Mortality from Drought1[OPEN

PubMed Central

Speckman, Heather N.; Huhn, Bridger J.; Strawn, Rachel N.; Weinig, Cynthia

2017-01-01

Climate models predict widespread increases in both drought intensity and duration in the next decades. Although water deficiency is a significant determinant of plant survival, limited understanding of plant responses to extreme drought impedes forecasts of both forest and crop productivity under increasing aridity. Drought induces a suite of physiological responses; however, we lack an accurate mechanistic description of plant response to lethal drought that would improve predictive understanding of mortality under altered climate conditions. Here, proxies for leaf cellular damage, chlorophyll a fluorescence, and electrolyte leakage were directly associated with failure to recover from drought upon rewatering in Brassica rapa (genotype R500) and thus define the exact timing of drought-induced death. We validated our results using a second genotype (imb211) that differs substantially in life history traits. Our study demonstrates that whereas changes in carbon dynamics and water transport are critical indicators of drought stress, they can be unrelated to visible metrics of mortality, i.e. lack of meristematic activity and regrowth. In contrast, membrane failure at the cellular scale is the most proximate cause of death. This hypothesis was corroborated in two gymnosperms (Picea engelmannii and Pinus contorta) that experienced lethal water stress in the field and in laboratory conditions. We suggest that measurement of chlorophyll a fluorescence can be used to operationally define plant death arising from drought, and improved plant characterization can enhance surface model predictions of drought mortality and its consequences to ecosystem services at a global scale. PMID:28710130

Dead or Alive? Using Membrane Failure and Chlorophyll a Fluorescence to Predict Plant Mortality from Drought.

PubMed

Guadagno, Carmela R; Ewers, Brent E; Speckman, Heather N; Aston, Timothy Llewellyn; Huhn, Bridger J; DeVore, Stanley B; Ladwig, Joshua T; Strawn, Rachel N; Weinig, Cynthia

2017-09-01

Climate models predict widespread increases in both drought intensity and duration in the next decades. Although water deficiency is a significant determinant of plant survival, limited understanding of plant responses to extreme drought impedes forecasts of both forest and crop productivity under increasing aridity. Drought induces a suite of physiological responses; however, we lack an accurate mechanistic description of plant response to lethal drought that would improve predictive understanding of mortality under altered climate conditions. Here, proxies for leaf cellular damage, chlorophyll a fluorescence, and electrolyte leakage were directly associated with failure to recover from drought upon rewatering in Brassica rapa (genotype R500) and thus define the exact timing of drought-induced death. We validated our results using a second genotype (imb211) that differs substantially in life history traits. Our study demonstrates that whereas changes in carbon dynamics and water transport are critical indicators of drought stress, they can be unrelated to visible metrics of mortality, i.e. lack of meristematic activity and regrowth. In contrast, membrane failure at the cellular scale is the most proximate cause of death. This hypothesis was corroborated in two gymnosperms ( Picea engelmannii and Pinus contorta ) that experienced lethal water stress in the field and in laboratory conditions. We suggest that measurement of chlorophyll a fluorescence can be used to operationally define plant death arising from drought, and improved plant characterization can enhance surface model predictions of drought mortality and its consequences to ecosystem services at a global scale. © 2017 American Society of Plant Biologists. All Rights Reserved.

Anesthetic effects on fictive locomotion in the rat isolated spinal cord

PubMed Central

Jinks, Steven L.; Andrada, Jason; Satter, Omar

2011-01-01

General anesthetic mechanisms are poorly understood. Anesthetic immobilizing effects occur in the spinal ventral horn. However, a detailed analysis of anesthetic effects on ventral motor networks is lacking. We delivered isoflurane, desflurane, or propofol during NMDA/5-HT-induced, or noxious tail stimulus-evoked, fictive locomotion in neonatal rat isolated spinal cords. Anesthetics changed the frequency, amplitude, and regularity of fictive locomotion with little effect on phase-lag. Isoflurane abolished pharmacologically-induced vs noxious stimulus-induced motor output at similar concentrations. Propofol abolished pharmacologically-induced fictive locomotion via a GABAA-receptor mechanism. Anesthetic effects on pharmacologically-elicted fictive locomotion appear clinically-relevant, and support a ventral horn immobilizing effect on locomotor rhythm generation. PMID:21817927

Generalized Kerker effects in nanophotonics and meta-optics [Invited

NASA Astrophysics Data System (ADS)

Liu, Wei; Kivshar, Yuri S.

2018-05-01

The original Kerker effect was introduced for a hypothetical magnetic sphere, and initially it did not attract much attention due to a lack of magnetic materials required. Rejuvenated by the recent explosive development of the field of metamaterials and especially its core concept of optically-induced artificial magnetism, the Kerker effect has gained an unprecedented impetus and rapidly pervaded different branches of nanophotonics. At the same time, the concept behind the effect itself has also been significantly expanded and generalized. Here we review the physics and various manifestations of the generalized Kerker effects, including the progress in the emerging field of meta-optics that focuses on interferences of electromagnetic multipoles of different orders and origins. We discuss not only the scattering by individual particles and particle clusters, but also the manipulation of reflection, transmission, diffraction, and absorption for metalattices and metasurfaces, revealing how various optical phenomena observed recently are all ubiquitously related to the Kerker's concept.

[Atypical antipsychotic-induced weight gain].

PubMed

Godlewska, Beata R; Olajossy-Hilkesberger, Luiza; Marmurowska-Michałowska, Halina; Olajossy, Marcin; Landowski, Jerzy

2006-01-01

Introduction of a new group of antipsychotic drugs, called atypical because of the proprieties differing them from classical neuroleptics, gave hope for the beginning of a new era in treatment of psychoses, including schizophrenia. Different mechanisms of action not only resulted in a broader spectrum of action and high efficacy but also in a relative lack of extrapiramidal symptoms. However, atypical neuroleptics are not totally free from adverse effects. Symptoms such as sedation, metabolic changes and weight gain, often very quick and severe - present also in the case of classical drugs, but put to the background by extrapiramidal symptoms--have become prominent. Weight gain is important both from the clinical and subjective point of view--as associated with serious somatic consequences and as a source of enormous mental distress. These problems are addressed in this review, with the focus on weight gain associated with the use of specific atypical neuroleptics.

Activation of the Cph1-Dependent MAP Kinase Signaling Pathway Induces White-Opaque Switching in Candida albicans

PubMed Central

Ramírez-Zavala, Bernardo; Weyler, Michael; Gildor, Tsvia; Schmauch, Christian; Kornitzer, Daniel; Arkowitz, Robert; Morschhäuser, Joachim

2013-01-01

Depending on the environmental conditions, the pathogenic yeast Candida albicans can undergo different developmental programs, which are controlled by dedicated transcription factors and upstream signaling pathways. C. albicans strains that are homozygous at the mating type locus can switch from the normal yeast form (white) to an elongated cell type (opaque), which is the mating-competent form of this fungus. Both white and opaque cells use the Ste11-Hst7-Cek1/Cek2 MAP kinase signaling pathway to react to the presence of mating pheromone. However, while opaque cells employ the transcription factor Cph1 to induce the mating response, white cells recruit a different downstream transcription factor, Tec1, to promote the formation of a biofilm that facilitates mating of opaque cells in the population. The switch from the white to the opaque cell form is itself induced by environmental signals that result in the upregulation of the transcription factor Wor1, the master regulator of white-opaque switching. To get insight into the upstream signaling pathways controlling the switch, we expressed all C. albicans protein kinases from a tetracycline-inducible promoter in a switching-competent strain. Screening of this library of strains showed that a hyperactive form of Ste11 lacking its N-terminal domain (Ste11ΔN467) efficiently stimulated white cells to switch to the opaque phase, a behavior that did not occur in response to pheromone. Ste11ΔN467-induced switching specifically required the downstream MAP kinase Cek1 and its target transcription factor Cph1, but not Cek2 and Tec1, and forced expression of Cph1 also promoted white-opaque switching in a Wor1-dependent manner. Therefore, depending on the activation mechanism, components of the pheromone-responsive MAP kinase pathway can be reconnected to stimulate an alternative developmental program, switching of white cells to the mating-competent opaque phase. PMID:24130492

Metamorphosis of a Scleractinian Coral in Response to Microbial Biofilms

PubMed Central

Webster, Nicole S.; Smith, Luke D.; Heyward, Andrew J.; Watts, Joy E. M.; Webb, Richard I.; Blackall, Linda L.; Negri, Andrew P.

2004-01-01

Microorganisms have been reported to induce settlement and metamorphosis in a wide range of marine invertebrate species. However, the primary cue reported for metamorphosis of coral larvae is calcareous coralline algae (CCA). Herein we report the community structure of developing coral reef biofilms and the potential role they play in triggering the metamorphosis of a scleractinian coral. Two-week-old biofilms induced metamorphosis in less than 10% of larvae, whereas metamorphosis increased significantly on older biofilms, with a maximum of 41% occurring on 8-week-old microbial films. There was a significant influence of depth in 4- and 8-week biofilms, with greater levels of metamorphosis occurring in response to shallow-water communities. Importantly, larvae were found to settle and metamorphose in response to microbial biofilms lacking CCA from both shallow and deep treatments, indicating that microorganisms not associated with CCA may play a significant role in coral metamorphosis. A polyphasic approach consisting of scanning electron microscopy, fluorescence in situ hybridization (FISH), and denaturing gradient gel electrophoresis (DGGE) revealed that coral reef biofilms were comprised of complex bacterial and microalgal communities which were distinct at each depth and time. Principal-component analysis of FISH data showed that the Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, and Cytophaga-Flavobacterium of Bacteroidetes had the largest influence on overall community composition. A low abundance of Archaea was detected in almost all biofilms, providing the first report of Archaea associated with coral reef biofilms. No differences in the relative densities of each subdivision of Proteobacteria were observed between slides that induced larval metamorphosis and those that did not. Comparative cluster analysis of bacterial DGGE patterns also revealed that there were clear age and depth distinctions in biofilm community structure; however, no difference was detected in banding profiles between biofilms which induced larval metamorphosis and those where no metamorphosis occurred. This investigation demonstrates that complex microbial communities can induce coral metamorphosis in the absence of CCA. PMID:14766608

Effect of Environmental Cues on Behavioral Efficacy of Haloperidol, Olanzapine and Clozapine in Rats

PubMed Central

Sun, Tao; Liu, Xinfeng; Li, Ming

2014-01-01

Previous studies have reported that context can powerfully modulate the inhibitory effect of an antipsychotic drug on phencyclidine (PCP)-induced hyperlocomotion (a behavioral test used to evaluate putative antipsychotic drugs). The present study investigated the experimental conditions under which environmental stimuli exert their influence through associative conditioning processes. Experiment 1 examined the extent to which prior antipsychotic treatment in the home cages affected a drug’s ability to inhibit PCP-induced hyperlocomotion in a novel motor activity test apparatus. Five days of repeated haloperidol (0.05 mg/kg, sc) and olanzapine (2.0 mg/kg, sc) treatment in the home cages still potentiated their inhibition of PCP-induced hyperlocomotion (i.e. sensitization) assessed in a new environment, whereas the clozapine (10.0 mg/kg, sc) treatment enhanced the development of clozapine tolerance, indicating a lack of environmental modulation of antipsychotic efficacy. Experiment 2 assessed the impact of different numbers of antipsychotic administrations in either the home environment or test environment (e.g. 4, 2 or 0) on a drug’s ability to inhibit PCP-induced hyperlocomotion. Repeated administration of clozapine (5.0 mg/kg, sc) or olanzapine (1.0 mg/kg, sc) for 4 consecutive days, regardless of where these treatments occurred, caused a similar level of inhibition on PCP-induced hyperlocomotion. However, 4-day haloperidol (0.03 mg/kg, sc) treatment in the test apparatus caused a significant higher inhibition than 4-day home cage treatment. Thus, more exposures to the test environment under the influence of haloperidol (but not clozapine or olanzapine) cause a stronger inhibition than fewer exposures, indicating a strong environmental modulation. Collectively, these findings suggest that prior antipsychotic treatment in one environment could alter later antipsychotic-like response assessed in a different environment under certain test conditions. Therefore, whether the circumstances surrounding antipsychotic drug administration exert a powerful control of the expression of antipsychotic-like efficacy is dependent on specific experimental and drug treatment factors. PMID:24949569

Effect of hop (Humulus lupulus L.) inclusion in the diet for fattening lambs on animal performance, ruminal characteristics and meat quality.

PubMed

Blanco, Carolina; Bodas, Raúl; Morán, Lara; Mateo, Javier; Andrés, Sonia; Giráldez, F Javier

2018-06-01

Thirty male merino lambs were fed with a pelleted total mixed ration (TMR) alone or supplemented with hop (Humulus lupulus L.) cones at two different doses (1.5 and 3.0 g hop cones/kg pelleted TMR, respectively), to study the effects of this dietary source of antioxidants on animal performance, ruminal parameters and meat quality attributes. The results showed that dietary supplementation with hop cones decreased lambs' growth rate (P < 0.05) due to a shift in ruminal fermentation, towards a more acetic and less propionic acid production (P < 0.05). These changes in animal growth rate might have promoted microstructural modifications in the quantity and size of muscle fibres, thereby inducing the differences observed in meat chemical composition, colour and texture (P < 0.05), regardless of the lack of differences in meat antioxidant status (P > 0.10). Copyright © 2018 Elsevier Ltd. All rights reserved.

Opposing effects of fructokinase C and A isoforms on fructose-induced metabolic syndrome in mice

PubMed Central

Ishimoto, Takuji; Lanaspa, Miguel A.; Le, MyPhuong T.; Garcia, Gabriela E.; Diggle, Christine P.; MacLean, Paul S.; Jackman, Matthew R.; Asipu, Aruna; Roncal-Jimenez, Carlos A.; Kosugi, Tomoki; Rivard, Christopher J.; Maruyama, Shoichi; Rodriguez-Iturbe, Bernardo; Sánchez-Lozada, Laura G.; Bonthron, David T.; Sautin, Yuri Y.; Johnson, Richard J.

2012-01-01

Fructose intake from added sugars correlates with the epidemic rise in obesity, metabolic syndrome, and nonalcoholic fatty liver disease. Fructose intake also causes features of metabolic syndrome in laboratory animals and humans. The first enzyme in fructose metabolism is fructokinase, which exists as two isoforms, A and C. Here we show that fructose-induced metabolic syndrome is prevented in mice lacking both isoforms but is exacerbated in mice lacking fructokinase A. Fructokinase C is expressed primarily in liver, intestine, and kidney and has high affinity for fructose, resulting in rapid metabolism and marked ATP depletion. In contrast, fructokinase A is widely distributed, has low affinity for fructose, and has less dramatic effects on ATP levels. By reducing the amount of fructose for metabolism in the liver, fructokinase A protects against fructokinase C-mediated metabolic syndrome. These studies provide insights into the mechanisms by which fructose causes obesity and metabolic syndrome. PMID:22371574

Development of exercise-induced arm-leg blood pressure gradient and abnormal arterial compliance in patients with repaired coarctation of the aorta.

PubMed

Markham, Larry W; Knecht, Sandra K; Daniels, Stephen R; Mays, Wayne A; Khoury, Philip R; Knilans, Timothy K

2004-11-01

Often, the lack of systemic arterial hypertension and the lack of a resting arm-leg blood pressure gradient are used to assess the adequacy of the anatomic result after intervention for coarctation of the aorta (CoA). Some patients with no arm-leg gradient at rest may develop a gradient with exercise, leading caregivers to question the success of the repair. It is not clear what the prevalence is of patients who have undergone a successful intervention for CoA and have no arm-leg gradient at rest but develop a significant gradient with exercise and which factors may predict the development of an arm-leg gradient with exercise. This study evaluates the prevalence and predictors of an exercise-induced arm-leg gradient in subjects who have undergone an apparently successful intervention for CoA.

Prototype Biology-Based Radiation Risk Module Project

NASA Technical Reports Server (NTRS)

Terrier, Douglas; Clayton, Ronald G.; Patel, Zarana; Hu, Shaowen; Huff, Janice

2015-01-01

Biological effects of space radiation and risk mitigation are strategic knowledge gaps for the Evolvable Mars Campaign. The current epidemiology-based NASA Space Cancer Risk (NSCR) model contains large uncertainties (HAT #6.5a) due to lack of information on the radiobiology of galactic cosmic rays (GCR) and lack of human data. The use of experimental models that most accurately replicate the response of human tissues is critical for precision in risk projections. Our proposed study will compare DNA damage, histological, and cell kinetic parameters after irradiation in normal 2D human cells versus 3D tissue models, and it will use a multi-scale computational model (CHASTE) to investigate various biological processes that may contribute to carcinogenesis, including radiation-induced cellular signaling pathways. This cross-disciplinary work, with biological validation of an evolvable mathematical computational model, will help reduce uncertainties within NSCR and aid risk mitigation for radiation-induced carcinogenesis.

Neuroanatomical Diversity of Corpus Callosum and Brain Volume in Autism: Meta-analysis, Analysis of the Autism Brain Imaging Data Exchange Project, and Simulation.

PubMed

Lefebvre, Aline; Beggiato, Anita; Bourgeron, Thomas; Toro, Roberto

2015-07-15

Patients with autism have been often reported to have a smaller corpus callosum (CC) than control subjects. We conducted a meta-analysis of the literature, analyzed the CC in 694 subjects of the Autism Brain Imaging Data Exchange project, and performed computer simulations to study the effect of different analysis strategies. Our meta-analysis suggested a group difference in CC size; however, the studies were heavily underpowered (20% power to detect Cohen's d = .3). In contrast, we did not observe significant differences in the Autism Brain Imaging Data Exchange cohort, despite having achieved 99% power. However, we observed that CC scaled nonlinearly with brain volume (BV): large brains had a proportionally smaller CC. Our simulations showed that because of this nonlinearity, CC normalization could not control for eventual BV differences, but using BV as a covariate in a linear model would. We also observed a weaker correlation of IQ and BV in cases compared with control subjects. Our simulations showed that matching populations by IQ could then induce artifactual BV differences. The lack of statistical power in the previous literature prevents us from establishing the reality of the claims of a smaller CC in autism, and our own analyses did not find any. However, the nonlinear relationship between CC and BV and the different correlation between BV and IQ in cases and control subjects may induce artifactual differences. Overall, our results highlight the necessity for open data sharing to provide a more solid ground for the discovery of neuroimaging biomarkers within the context of the wide human neuroanatomical diversity. Copyright © 2015 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

A functional magnetic resonance imaging study of human brain in pain-related areas induced by electrical stimulation with different intensities.

PubMed

Yuan, Wang; Ming, Zhang; Rana, Netra; Hai, Liu; Chen-wang, Jin; Shao-hui, Ma

2010-01-01

Pain-related studies have mainly been performed through traditional methods, which lack the rigorous analysis of anatomical locations. Functional magnetic resonance imaging (fMRI) is a noninvasive method detecting neural activity, and has the ability to precisely locate related activations in vivo. Moreover, few studies have used painful stimulation of changed intensity to investigate relevant functioning nuclei in the human brain. This study mainly focused on the pain-related activations induced by electrical stimulation with different intensities using fMRI. Furthermore, the electrophysiological characteristics of different pain-susceptible-neurons were analyzed to construct the pain modulatory network, which was corresponding to painful stimulus of changed intensity. Twelve volunteers underwent functional scanning receiving different electrical stimulation. The data were collected and analyzed to generate the corresponding functional activation maps and response time curves related to pain. The common activations were mainly located in several specific regions, including the secondary somatosensory cortex (SII), insula, anterior cingulate cortex (ACC), thalamus, and other cerebral regions. Moreover, innocuous electrical stimulation primarily activated the lateral portions of SII and thalamus, as well as the posterior insula, anterior ACC, whereas noxious electrical stimulation primarily activated the medial portions of SII and thalamus, as well as the anterior insula, the posterior ACC, with larger extensions and greater intensities. Several specified cerebral regions displayed different response patterns during electrical stimulation by means of fMRI, which implied that the corresponding pain-susceptible-neurons might process specific aspects of pain. Elucidation of functions on pain-related regions will help to understand the delicate pain modulation of human brain.

Glutamatergic and Dopaminergic Neurons in the Mouse Ventral Tegmental Area

PubMed Central

Yamaguchi, Tsuyoshi; Qi, Jia; Wang, Hui-Ling; Zhang, Shiliang; Morales, Marisela

2014-01-01

The ventral tegmental area (VTA) comprises dopamine (DA), GABA and glutamate (Glu) neurons. Some rat VTA Glu neurons, expressing vesicular glutamate transporter 2 (VGluT2), co-express tyrosine hydroxylase (TH). While transgenic mice are now being used in attempts to determine the role of VGluT2/TH neurons in reward and neuronal signaling, such neurons have not been characterized in mouse tissue. By cellular detection of VGluT2-mRNA and TH-immunoreactivity (TH-IR), we determined the cellular expression of VGluT2-mRNA within VTA TH-IR neurons in the mouse. We found that some mouse VGluT2 neurons co-expressed TH-IR, but their frequency was lower than in the rat. To determine whether low expression of TH mRNA or TH-IR accounts for this low frequency, we evaluated VTA cellular co-expression of TH-transcripts and TH-protein. Within the medial aspects of the VTA, some neurons expressed TH mRNA but lacked TH-IR; among them a subset co-expressed VGluT2 mRNA. To determine if lack of VTA TH-IR was due to TH trafficking, we tagged VTA TH neurons by cre-inducible expression of mCherry in TH::Cre mice. By dual immunofluorescence, we detected axons containing mCherry, but lacking TH-IR, in the lateral habenula, indicating that mouse low frequency of VGluT2 mRNA (+)/TH-IR (+) neurons is due to lack of synthesis of TH protein, rather than TH-protein trafficking. In conclusion, VGluT2 neurons are present in the rat and mouse VTA, but they differ in the populations of VGluT2/TH and TH neurons. We reveal that under normal conditions, the translation of TH protein is suppressed in the mouse mesohabenular TH neurons. PMID:25572002

Bioelectric characterization of epithelia from neonatal CFTR knockout ferrets.

PubMed

Fisher, John T; Tyler, Scott R; Zhang, Yulong; Lee, Ben J; Liu, Xiaoming; Sun, Xingshen; Sui, Hongshu; Liang, Bo; Luo, Meihui; Xie, Weiliang; Yi, Yaling; Zhou, Weihong; Song, Yi; Keiser, Nicholas; Wang, Kai; de Jonge, Hugo R; Engelhardt, John F

2013-11-01

Cystic fibrosis (CF) is a life-shortening, recessive, multiorgan genetic disorder caused by the loss of CF transmembrane conductance regulator (CFTR) chloride channel function found in many types of epithelia. Animal models that recapitulate the human disease phenotype are critical to understanding pathophysiology in CF and developing therapies. CFTR knockout ferrets manifest many of the phenotypes observed in the human disease, including lung infections, pancreatic disease and diabetes, liver disease, malnutrition, and meconium ileus. In the present study, we have characterized abnormalities in the bioelectric properties of the trachea, stomach, intestine, and gallbladder of newborn CF ferrets. Short-circuit current (ISC) analysis of CF and wild-type (WT) tracheas revealed the following similarities and differences: (1) amiloride-sensitive sodium currents were similar between genotypes; (2) responses to 4,4'-diisothiocyano-2,2'-stilbene disulphonic acid were 3.3-fold greater in CF animals, suggesting elevated baseline chloride transport through non-CFTR channels in a subset of CF animals; and (3) a lack of 3-isobutyl-1-methylxanthine (IBMX)/forskolin-stimulated and N-(2-Naphthalenyl)-((3,5-dibromo-2,4-dihydroxyphenyl)methylene)glycine hydrazide (GlyH-101)-inhibited currents in CF animals due to the lack of CFTR. CFTR mRNA was present throughout all levels of the WT ferret and IBMX/forskolin-inducible ISC was only observed in WT animals. However, despite the lack of CFTR function in the knockout ferret, the luminal pH of the CF ferret gallbladder, stomach, and intestines was not significantly changed relative to WT. The WT stomach and gallbladder exhibited significantly enhanced IBMX/forskolin ISC responses and inhibition by GlyH-101 relative to CF samples. These findings demonstrate that multiple organs affected by disease in the CF ferret have bioelectric abnormalities consistent with the lack of cAMP-mediated chloride transport.

An experimental approach to improve the Monte Carlo modelling of offline PET/CT-imaging of positron emitters induced by scanned proton beams

NASA Astrophysics Data System (ADS)

Bauer, J.; Unholtz, D.; Kurz, C.; Parodi, K.

2013-08-01

We report on the experimental campaign carried out at the Heidelberg Ion-Beam Therapy Center (HIT) to optimize the Monte Carlo (MC) modelling of proton-induced positron-emitter production. The presented experimental strategy constitutes a pragmatic inverse approach to overcome the known uncertainties in the modelling of positron-emitter production due to the lack of reliable cross-section data for the relevant therapeutic energy range. This work is motivated by the clinical implementation of offline PET/CT-based treatment verification at our facility. Here, the irradiation induced tissue activation in the patient is monitored shortly after the treatment delivery by means of a commercial PET/CT scanner and compared to a MC simulated activity expectation, derived under the assumption of a correct treatment delivery. At HIT, the MC particle transport and interaction code FLUKA is used for the simulation of the expected positron-emitter yield. For this particular application, the code is coupled to externally provided cross-section data of several proton-induced reactions. Studying experimentally the positron-emitting radionuclide yield in homogeneous phantoms provides access to the fundamental production channels. Therefore, five different materials have been irradiated by monoenergetic proton pencil beams at various energies and the induced β+ activity subsequently acquired with a commercial full-ring PET/CT scanner. With the analysis of dynamically reconstructed PET images, we are able to determine separately the spatial distribution of different radionuclide concentrations at the starting time of the PET scan. The laterally integrated radionuclide yields in depth are used to tune the input cross-section data such that the impact of both the physical production and the imaging process on the various positron-emitter yields is reproduced. The resulting cross-section data sets allow to model the absolute level of measured β+ activity induced in the investigated targets within a few per cent. Moreover, the simulated distal activity fall-off positions, representing the central quantity for treatment monitoring in terms of beam range verification, are found to agree within 0.6 mm with the measurements at different initial beam energies in both homogeneous and heterogeneous targets. Based on work presented at the Third European Workshop on Monte Carlo Treatment Planning (Seville, 15-18 May 2012).

Induced pluripotent stem cells with a pathological mitochondrial DNA deletion

PubMed Central

Cherry, Anne B. C.; Gagne, Katelyn E.; McLoughlin, Erin M.; Baccei, Anna; Gorman, Bryan; Hartung, Odelya; Miller, Justine D.; Zhang, Jin; Zon, Rebecca L.; Ince, Tan A.; Neufeld, Ellis J.; Lerou, Paul H.; Fleming, Mark D.; Daley, George Q.; Agarwal, Suneet

2013-01-01

In congenital mitochondrial DNA (mtDNA) disorders, a mixture of normal and mutated mtDNA (termed heteroplasmy) exists at varying levels in different tissues, which determines the severity and phenotypic expression of disease. Pearson marrow pancreas syndrome (PS) is a congenital bone marrow failure disorder caused by heteroplasmic deletions in mtDNA. The cause of the hematopoietic failure in PS is unknown, and adequate cellular and animal models are lacking. Induced pluripotent stem (iPS) cells are particularly amenable for studying mtDNA disorders, as cytoplasmic genetic material is retained during direct reprogramming. Here we derive and characterize iPS cells from a patient with PS. Taking advantage of the tendency for heteroplasmy to change with cell passage, we isolated isogenic PS-iPS cells without detectable levels of deleted mtDNA. We found that PS-iPS cells carrying a high burden of deleted mtDNA displayed differences in growth, mitochondrial function, and hematopoietic phenotype when differentiated in vitro, compared to isogenic iPS cells without deleted mtDNA. Our results demonstrate that reprogramming somatic cells from patients with mtDNA disorders can yield pluripotent stem cells with varying burdens of heteroplasmy that might be useful in the study and treatment of mitochondrial diseases. PMID:23400930

Nanoparticles for the delivery of zoledronic acid to prostate cancer cells: A comparative analysis through time lapse video-microscopy technique

PubMed Central

Schiraldi, Chiara; Zappavigna, Silvia; D' Agostino, Antonella; Porto, Stefania; Gaito, Ornella; Lusa, Sara; Lamberti, Monica; De Rosa, Mario; De Rosa, Giuseppe; Caraglia, Michele

2014-01-01

Time-lapse live cell imaging is a powerful tool for studying the responses of cells to drugs. Zoledronic acid (ZOL) is the most potent aminobiphosphonate able to induce cell growth inhibition at very low concentrations. The lack of clear evidence of ZOL-induced anti-cancer effects is likely due to its unfavorable pharmacokinetic profile. The use of nanotechnology-based formulations allows overcoming these limitations in ZOL pharmaco-distribution. Recently, stealth liposomes (LIPOs) and new self-assembly PEGylated nanoparticles (NPs) encapsulating ZOL were developed. Both the delivery systems showed promising anticancer activity in vitro and in vivo. In this work, we investigated the cytostatic effect of these novel formulations (LIPOs and NPs) compared with free ZOL on 2 different prostate cancer cell lines, PC 3 and DU 145 and on prostate epithelial primary cells EPN using time lapse video-microscopy (TLVM). In PC3 cells, free ZOL showed a significant anti-proliferative effect but this effect was lower than that induced by LIPOs and NPs encapsulating ZOL; moreover, LIPO-ZOL was more potent in inducing growth inhibition than NP-ZOL. On the other hand, LIPO-ZOL slightly enhanced the free ZOL activity on growth inhibition of DU 145, while the anti-proliferative effect of NP-ZOL was not statistically relevant. These novel formulations did not induce anti-proliferative effects on EPN cells. Finally, we evaluated cytotoxic effects on DU145 where, LIPO-ZOL induced the highest cytotoxicity compared with NP-ZOL and free ZOL. In conclusion, ZOL can be transformed in a powerful anticancer agent, if administered with nanotechnology-based formulations without damaging the healthy tissues. PMID:25482949

Fractalkine is a "find-me" signal released by neurons undergoing ethanol-induced apoptosis.

PubMed

Sokolowski, Jennifer D; Chabanon-Hicks, Chloe N; Han, Claudia Z; Heffron, Daniel S; Mandell, James W

2014-01-01

Apoptotic neurons generated during normal brain development or secondary to pathologic insults are efficiently cleared from the central nervous system. Several soluble factors, including nucleotides, cytokines, and chemokines are released from injured neurons, signaling microglia to find and clear debris. One such chemokine that serves as a neuronal-microglial communication factor is fractalkine, with roles demonstrated in several models of adult neurological disorders. Lacking, however, are studies investigating roles for fractalkine in perinatal brain injury, an important clinical problem with no effective therapies. We used a well-characterized mouse model of ethanol-induced apoptosis to assess the role of fractalkine in neuronal-microglial signaling. Quantification of apoptotic debris in fractalkine-knockout (KO) and CX3CR1-KO mice following ethanol treatment revealed increased apoptotic bodies compared to wild type mice. Ethanol-induced injury led to release of soluble, extracellular fractalkine. The extracellular media harvested from apoptotic brains induces microglial migration in a fractalkine-dependent manner that is prevented by neutralization of fractalkine with a blocking antibody or by deficiency in the receptor, CX3CR1. This suggests fractalkine acts as a "find-me" signal, recruiting microglial processes toward apoptotic cells to promote their clearance. Next, we aimed to determine whether there are downstream alterations in cytokine gene expression due to fractalkine signaling. We examined mRNA expression in fractalkine-KO and CX3CR1-KO mice after alcohol-induced apoptosis and found differences in cytokine production in the brains of these KOs by 6 h after ethanol treatment. Collectively, this suggests that fractalkine acts as a "find me" signal released by apoptotic neurons, and subsequently plays a critical role in modulating both clearance and inflammatory cytokine gene expression after ethanol-induced apoptosis.

Distinct Contributions of TNF Receptor 1 and 2 to TNF-Induced Glomerular Inflammation in Mice

PubMed Central

Taubitz, Anela; Schwarz, Martin; Eltrich, Nuru; Lindenmeyer, Maja T.; Vielhauer, Volker

2013-01-01

TNF is an important mediator of glomerulonephritis. The two TNF-receptors TNFR1 and TNFR2 contribute differently to glomerular inflammation in vivo, but specific mechanisms of TNFR-mediated inflammatory responses in glomeruli are unknown. We investigated their expression and function in murine kidneys, isolated glomeruli ex vivo, and glomerular cells in vitro. In normal kidney TNFR1 and TNFR2 were preferentially expressed in glomeruli. Expression of both TNFRs and TNF-induced upregulation of TNFR2 mRNA was confirmed in murine glomerular endothelial and mesangial cell lines. In vivo, TNF exposure rapidly induced glomerular accumulation of leukocytes. To examine TNFR-specific inflammatory responses in intrinsic glomerular cells but not infiltrating leukocytes we performed microarray gene expression profiling on intact glomeruli isolated from wildtype and Tnfr-deficient mice following exposure to soluble TNF ex vivo. Most TNF-induced effects were exclusively mediated by TNFR1, including induced glomerular expression of adhesion molecules, chemokines, complement factors and pro-apoptotic molecules. However, TNFR2 contributed to TNFR1-dependent mRNA expression of inflammatory mediators in glomeruli when exposed to low TNF concentrations. Chemokine secretion was absent in TNF-stimulated Tnfr1-deficient glomeruli, but also significantly decreased in glomeruli lacking TNFR2. In vivo, TNF-induced glomerular leukocyte infiltration was abrogated in Tnfr1-deficient mice, whereas Tnfr2-deficiency decreased mononuclear phagocytes infiltrates, but not neutrophils. These data demonstrate that activation of intrinsic glomerular cells by soluble TNF requires TNFR1, whereas TNFR2 is not essential, but augments TNFR1-dependent effects. Previously described TNFR2-dependent glomerular inflammation may therefore require TNFR2 activation by membrane-bound, but not soluble TNF. PMID:23869211

Acetazolamide Attenuates Lithium-Induced Nephrogenic Diabetes Insipidus.

PubMed

de Groot, Theun; Sinke, Anne P; Kortenoeven, Marleen L A; Alsady, Mohammad; Baumgarten, Ruben; Devuyst, Olivier; Loffing, Johannes; Wetzels, Jack F; Deen, Peter M T

2016-07-01

To reduce lithium-induced nephrogenic diabetes insipidus (lithium-NDI), patients with bipolar disorder are treated with thiazide and amiloride, which are thought to induce antidiuresis by a compensatory increase in prourine uptake in proximal tubules. However, thiazides induced antidiuresis and alkalinized the urine in lithium-NDI mice lacking the sodium-chloride cotransporter, suggesting that inhibition of carbonic anhydrases (CAs) confers the beneficial thiazide effect. Therefore, we tested the effect of the CA-specific blocker acetazolamide in lithium-NDI. In collecting duct (mpkCCD) cells, acetazolamide reduced the cellular lithium content and attenuated lithium-induced downregulation of aquaporin-2 through a mechanism different from that of amiloride. Treatment of lithium-NDI mice with acetazolamide or thiazide/amiloride induced similar antidiuresis and increased urine osmolality and aquaporin-2 abundance. Thiazide/amiloride-treated mice showed hyponatremia, hyperkalemia, hypercalcemia, metabolic acidosis, and increased serum lithium concentrations, adverse effects previously observed in patients but not in acetazolamide-treated mice in this study. Furthermore, acetazolamide treatment reduced inulin clearance and cortical expression of sodium/hydrogen exchanger 3 and attenuated the increased expression of urinary PGE2 observed in lithium-NDI mice. These results show that the antidiuresis with acetazolamide was partially caused by a tubular-glomerular feedback response and reduced GFR. The tubular-glomerular feedback response and/or direct effect on collecting duct principal or intercalated cells may underlie the reduced urinary PGE2 levels with acetazolamide, thereby contributing to the attenuation of lithium-NDI. In conclusion, CA activity contributes to lithium-NDI development, and acetazolamide attenuates lithium-NDI development in mice similar to thiazide/amiloride but with fewer adverse effects. Copyright © 2016 by the American Society of Nephrology.

Germinal Center B Cell and T Follicular Helper Cell Responses to Viral Vector and Protein-in-Adjuvant Vaccines

PubMed Central

Wang, Chuan; Hart, Matthew; Chui, Cecilia; Ajuogu, Augustine; Brian, Iona J.; de Cassan, Simone C.; Borrow, Persephone; Draper, Simon J.

2016-01-01

There is great interest in the development of Ab-inducing subunit vaccines targeting infections, including HIV, malaria, and Ebola. We previously reported that adenovirus vectored vaccines are potent in priming Ab responses, but uncertainty remains regarding the optimal approach for induction of humoral immune responses. In this study, using OVA as a model Ag, we assessed the magnitude of the primary and anamnestic Ag–specific IgG responses of mice to four clinically relevant vaccine formulations: replication-deficient adenovirus; modified vaccinia Ankara (a poxvirus); protein with alum; and protein in the squalene oil-in-water adjuvant Addavax. We then used flow cytometric assays capable of measuring total and Ag-specific germinal center (GC) B cell and follicular Th cell responses to compare the induction of these responses by the different formulations. We report that adenovirus vectored vaccines induce Ag insert–specific GC B cell and Ab responses of a magnitude comparable to those induced by a potent protein/squalene oil-in-water formulation whereas—despite a robust overall GC response—the insert-specific GC B cell and Ab responses induced by modified vaccinia Ankara were extremely weak. Ag-specific follicular Th cell responses to adenovirus vectored vaccines exceeded those induced by other platforms at day 7 after immunization. We found little evidence that innate immune activation by adenovirus may act as an adjuvant in such a manner that the humoral response to a recombinant protein may be enhanced by coadministering with an adenovirus lacking a transgene of interest. Overall, these studies provide further support for the use of replication-deficient adenoviruses to induce humoral responses. PMID:27412417

Convergent evolution of heat-inducibility during subfunctionalization of the Hsp70 gene family

PubMed Central

2013-01-01

Background Heat-shock proteins of the 70 kDa family (Hsp70s) are essential chaperones required for key cellular functions. In eukaryotes, four subfamilies can be distinguished according to their function and localisation in different cellular compartments: cytosol, endoplasmic reticulum, mitochondria and chloroplasts. Generally, multiple cytosol-type Hsp70s can be found in metazoans that show either constitutive expression and/or stress-inducibility, arguing for the evolution of different tasks and functions. Information about the hsp70 copy number and diversity in microbial eukaryotes is, however, scarce, and detailed knowledge about the differential gene expression in most protists is lacking. Therefore, we have characterised the Hsp70 gene family of Paramecium caudatum to gain insight into the evolution and differential heat stress response of the distinct family members in protists and to investigate the diversification of eukaryotic hsp70s focusing on the evolution of heat-inducibility. Results Eleven putative hsp70 genes could be detected in P. caudatum comprising homologs of three major Hsp70-subfamilies. Phylogenetic analyses revealed five evolutionarily distinct Hsp70-groups, each with a closer relationship to orthologous sequences of Paramecium tetraurelia than to another P. caudatum Hsp70-group. These highly diverse, paralogous groups resulted from duplications preceding Paramecium speciation, underwent divergent evolution and were subject to purifying selection. Heat-shock treatments were performed to test for differential expression patterns among the five Hsp70-groups as well as for a functional conservation within Paramecium. These treatments induced exceptionally high mRNA up-regulations in one cytosolic group with a low basal expression, indicative for the major heat inducible hsp70s. All other groups showed comparatively high basal expression levels and moderate heat-inducibility, signifying constitutively expressed genes. Comparative EST analyses for P. tetraurelia hsp70s unveiled a corresponding expression pattern, which supports a functionally conserved evolution of the Hsp70 gene family in Paramecium. Conclusions Our analyses suggest an independent evolution of the heat-inducible cytosol-type hsp70s in Paramecium and in its close relative Tetrahymena, as well as within higher eukaryotes. This result indicates convergent evolution during hsp70 subfunctionalization and implies that heat-inducibility evolved several times during the course of eukaryotic evolution. PMID:23433225

Reversible air-induced optical and electrical modulation of methylammonium lead bromide (MAPbBr3) single crystals

NASA Astrophysics Data System (ADS)

Zhang, Huotian; Liu, Yiting; Lu, Haizhou; Deng, Wan; Yang, Kang; Deng, Zunyi; Zhang, Xingmin; Yuan, Sijian; Wang, Jiao; Niu, Jiaxin; Zhang, Xiaolei; Jin, Qingyuan; Feng, Hongjian; Zhan, Yiqiang; Zheng, Lirong

2017-09-01

The photoluminescence (PL) variations of organic-inorganic hybrid lead halide perovskites in different atmospheres are well documented, while the fundamental mechanism still lacks comprehensive understandings. This study reports the reversible optical and electrical properties of methylammonium lead bromide (MAPbBr3 or CH3NH3PbBr3) single crystals caused by air infiltration. With the change in the surrounding atmosphere from air to vacuum, the PL intensity of perovskite single crystals decreases, while the conductivity increases. By means of first-principles computational studies, the shallow trap states are considered as key elements in PL and conductivity changes. These results have important implications for the characterization and application of organic-inorganic hybrid lead halide perovskites in vacuum.

Multi-level characterization of balanced inhibitory-excitatory cortical neuron network derived from human pluripotent stem cells.

PubMed

Nadadhur, Aishwarya G; Emperador Melero, Javier; Meijer, Marieke; Schut, Desiree; Jacobs, Gerbren; Li, Ka Wan; Hjorth, J J Johannes; Meredith, Rhiannon M; Toonen, Ruud F; Van Kesteren, Ronald E; Smit, August B; Verhage, Matthijs; Heine, Vivi M

2017-01-01

Generation of neuronal cultures from induced pluripotent stem cells (hiPSCs) serve the studies of human brain disorders. However we lack neuronal networks with balanced excitatory-inhibitory activities, which are suitable for single cell analysis. We generated low-density networks of hPSC-derived GABAergic and glutamatergic cortical neurons. We used two different co-culture models with astrocytes. We show that these cultures have balanced excitatory-inhibitory synaptic identities using confocal microscopy, electrophysiological recordings, calcium imaging and mRNA analysis. These simple and robust protocols offer the opportunity for single-cell to multi-level analysis of patient hiPSC-derived cortical excitatory-inhibitory networks; thereby creating advanced tools to study disease mechanisms underlying neurodevelopmental disorders.

Blue light-mediated transcriptional activation and repression of gene expression in bacteria

PubMed Central

Jayaraman, Premkumar; Devarajan, Kavya; Chua, Tze Kwang; Zhang, Hanzhong; Gunawan, Erry; Poh, Chueh Loo

2016-01-01

Light-regulated modules offer unprecedented new ways to control cellular behavior in precise spatial and temporal resolution. The availability of such tools may dramatically accelerate the progression of synthetic biology applications. Nonetheless, current optogenetic toolbox of prokaryotes has potential issues such as lack of rapid and switchable control, less portable, low dynamic expression and limited parts. To address these shortcomings, we have engineered a novel bidirectional promoter system for Escherichia coli that can be induced or repressed rapidly and reversibly using the blue light dependent DNA-binding protein EL222. We demonstrated that by modulating the dosage of light pulses or intensity we could control the level of gene expression precisely. We show that both light-inducible and repressible system can function in parallel with high spatial precision in a single cell and can be switched stably between ON- and OFF-states by repetitive pulses of blue light. In addition, the light-inducible and repressible expression kinetics were quantitatively analysed using a mathematical model. We further apply the system, for the first time, to optogenetically synchronize two receiver cells performing different logic behaviors over time using blue light as a molecular clock signal. Overall, our modular approach layers a transformative platform for next-generation light-controllable synthetic biology systems in prokaryotes. PMID:27353329

Optogenetic Activation of the Sensorimotor Cortex Reveals "Local Inhibitory and Global Excitatory" Inputs to the Basal Ganglia.

PubMed

Ozaki, Mitsunori; Sano, Hiromi; Sato, Shigeki; Ogura, Mitsuhiro; Mushiake, Hajime; Chiken, Satomi; Nakao, Naoyuki; Nambu, Atsushi

2017-12-01

To understand how information from different cortical areas is integrated and processed through the cortico-basal ganglia pathways, we used optogenetics to systematically stimulate the sensorimotor cortex and examined basal ganglia activity. We utilized Thy1-ChR2-YFP transgenic mice, in which channelrhodopsin 2 is robustly expressed in layer V pyramidal neurons. We applied light spots to the sensorimotor cortex in a grid pattern and examined neuronal responses in the globus pallidus (GP) and entopeduncular nucleus (EPN), which are the relay and output nuclei of the basal ganglia, respectively. Light stimulation typically induced a triphasic response composed of early excitation, inhibition, and late excitation in GP/EPN neurons. Other response patterns lacking 1 or 2 of the components were also observed. The distribution of the cortical sites whose stimulation induced a triphasic response was confined, whereas stimulation of the large surrounding areas induced early and late excitation without inhibition. Our results suggest that cortical inputs to the GP/EPN are organized in a "local inhibitory and global excitatory" manner. Such organization seems to be the neuronal basis for information processing through the cortico-basal ganglia pathways, that is, releasing and terminating necessary information at an appropriate timing, while simultaneously suppressing other unnecessary information. © The Author 2017. Published by Oxford University Press.

Mycobacterium tuberculosis manipulates pulmonary APCs subverting early immune responses.

PubMed

Garcia-Romo, Gina S; Pedroza-Gonzalez, Alexander; Lambrecht, Bart N; Aguilar-Leon, Diana; Estrada-Garcia, Iris; Hernandez-Pando, Rogelio; Flores-Romo, Leopoldo

2013-03-01

Alveolar macrophages (AM) and dendritic cells (DCs) are the main antigen presenting cells (APCs) in the respiratory tract. Whereas macrophages have been extensively studied in tuberculosis, in situ interactions of DC with Mycobacterium tuberculosis (Mtb) are poorly explored. We aimed to characterize lung APCs during pulmonary tuberculosis in Balb/C mice infected with Mtb H37Rv. Mtb-infection via the airways induced a delayed and continuous accumulation of DCs and AM in the lungs. While lung DCs increased after day 3 post-infection, macrophages increased after 2-3 weeks. Although both populations accumulated in lungs during the infection, DCs decreased in the late stages. Infection induced differential expression of co-stimulatory molecules in these lung APCs, decreasing to basal levels in both APCs in the late stages. A remarkable segregation was found regarding bacillary burden. Many macrophages contained numerous bacilli, but DC contained scarce mycobacteria or none. Mtb-infection also induced delayed accumulation of DC in draining lymph nodes. This delayed recruitment was not associated with a lack of IL-12p40, which was detected from day 3 post-infection. Although AM and lung DCs behave differently during pulmonary tuberculosis, Mtb apparently manipulates both lung APCs subverting early protective responses resulting in disease progression. Copyright © 2012 Elsevier GmbH. All rights reserved.

Effects of paternal deprivation on cocaine-induced behavioral response and hypothalamic oxytocin immunoreactivity and serum oxytocin level in female mandarin voles.

PubMed

Wang, Jianli; Fang, Qianqian; Yang, Chenxi

2017-09-15

Early paternal behavior plays a critical role in behavioral development in monogamous species. The vast majority of laboratory studies investigating the influence of parental behavior on cocaine vulnerability focus on the effects of early maternal separation. However, comparable studies on whether early paternal deprivation influences cocaine-induced behavioral response are substantially lacking. Mandarin vole (Microtus mandarinus) is a monogamous rodent with high levels of paternal care. After mandarin vole pups were subjected to early paternal deprivation, acute cocaine- induced locomotion, anxiety- like behavior and social behavior were examined in 45day old female pups, while hypothalamic oxytocin immunoreactivity and serum oxytocin level were also assessed. We found that cocaine increased locomotion and decreased social investigation, contact behavior and serum oxytocin level regardless of paternal care. Cocaine increased anxiety levels and decreased oxytocin immunoreactive neurons of the paraventricular nuclei and supraoptic nuclei in the bi-parental care group, whilst there were no specific effects in the paternal deprivation group. These results indicate that paternal deprivation results in different behavioral response to acute cocaine exposure in adolescents, which may be in part associated with the alterations in oxytocin immunoreactivity and peripheral OT level. Copyright © 2017 Elsevier B.V. All rights reserved.

Inducing death in tumor cells: roles of the inhibitor of apoptosis proteins.

PubMed

Finlay, Darren; Teriete, Peter; Vamos, Mitchell; Cosford, Nicholas D P; Vuori, Kristiina

2017-01-01

The heterogeneous group of diseases collectively termed cancer results not just from aberrant cellular proliferation but also from a lack of accompanying homeostatic cell death. Indeed, cancer cells regularly acquire resistance to programmed cell death, or apoptosis, which not only supports cancer progression but also leads to resistance to therapeutic agents. Thus, various approaches have been undertaken in order to induce apoptosis in tumor cells for therapeutic purposes. Here, we will focus our discussion on agents that directly affect the apoptotic machinery itself rather than on drugs that induce apoptosis in tumor cells indirectly, such as by DNA damage or kinase dependency inhibition. As the roles of the Bcl-2 family have been extensively studied and reviewed recently, we will focus in this review specifically on the inhibitor of apoptosis protein (IAP) family. IAPs are a disparate group of proteins that all contain a baculovirus IAP repeat domain, which is important for the inhibition of apoptosis in some, but not all, family members. We describe each of the family members with respect to their structural and functional similarities and differences and their respective roles in cancer. Finally, we also review the current state of IAPs as targets for anti-cancer therapeutics and discuss the current clinical state of IAP antagonists.

Magnetic field tunable dielectric dispersion in successive field-induced magnetic phases of the geometrically frustrated magnet CuFeO2 up to 28 T

NASA Astrophysics Data System (ADS)

Tamatsukuri, H.; Mitsuda, S.; Hiroura, K.; Nakajima, T.; Fujihala, M.; Yamano, M.; Toshioka, Y.; Kaneko, C.; Takehana, K.; Imanaka, Y.; Terada, N.; Kitazawa, H.

2018-06-01

We find magnetic-field-dependent dielectric dispersions specific to successive field-induced magnetic phases of a geometrically frustrated magnet CuFeO2 up to 28 T. The dielectric dispersions in the three field-induced collinear-commensurate magnetic phases are well described by the superposition of Debye-type relaxations, and the number of contributions to the Debye-type dispersions differs in these phases. In contrast, the dielectric dispersions in the noncollinear-incommensurate phase, known as a spin-driven ferroelectric phase, cannot be simply described by the Debye-type relaxations. In addition, we find that the temperature dependence of the Debye relaxation frequencies follows the Arrhenius law, and that the activation energies derived from the Arrhenius equation also depend on the magnetic field. Considering the magnetostriction effect in combination with elongation/contraction of spins resulting from the application of a magnetic field, we show that the number of Debye relaxation components is equivalent to the number of states of local Fe3O clusters determined by oxygen displacement within a triangular Fe lattice. Based on this correspondence, we propose a possible explanation that excess charges resulting from a lack of stoichiometry hop over the double-well potentials within each local Fe3O cluster, like small polarons.

Comparison of the effects of pathogenic simian human immunodeficiency virus strains SHIV-89.6P and SHIV-KU2 in cynomolgus macaques.

PubMed

Pawar, Santosh N; Mattila, Joshua T; Sturgeon, Timothy J; Lin, Philana Ling; Narayan, Opendra; Montelaro, Ronald C; Flynn, Joanne L

2008-04-01

Factors explaining why human immunodeficiency virus (HIV) enhances the risk of reactivated tuberculosis (TB) are poorly understood. Unfortunately, experimental models of HIV-induced reactivated TB are lacking. We examined whether cynomolgus macaques, which accurately model latent TB in humans, could be used to model pathogenesis of HIV infection in the lungs and associated lymph nodes. These experiments precede studies modeling the effects of HIV infection on latent TB. We infected two groups of macaques with chimeric simian-human immunodeficiency viruses (SHIV-89.6P and SHIV-KU2) and followed viral titers and immunologic parameters including lymphocytes numbers and phenotype in the blood, bronchoalveolar lavage cells, and lymph nodes over the course of infection. Tissues from the lungs, liver, kidney, spleen, and lymph nodes were similarly examined at necropsy. Both strains produced dramatic CD4(+) T cell depletion. Plasma titers were not different between viruses, but we found more SHIV-89.6P in the lungs. Both viruses induced similar patterns of cell activation markers. SHIV-89.6P induced more IFN-gamma expression than SHIV-KU2. These results indicate SHIV-89.6P and SHIV-KU2 infect cynomolgus macaques and may be used to accurately model effects of HIV infection on latent TB.

Lack of Additive Effects of Resveratrol and Energy Restriction in the Treatment of Hepatic Steatosis in Rats

PubMed Central

Aguirre, Leixuri; Rolo, Anabela P.; Palmeira, Carlos M.; Portillo, María P.

2017-01-01

The aims of the present study were to analyze the effect of resveratrol on liver steatosis in obese rats, to compare the effects induced by resveratrol and energy restriction and to research potential additive effects. Rats were initially fed a high-fat high-sucrose diet for six weeks and then allocated in four experimental groups fed a standard diet: a control group, a resveratrol-treated group, an energy restricted group and a group submitted to energy restriction and treated with resveratrol. We measured liver triacylglycerols, transaminases, FAS, MTP, CPT1a, CS, COX, SDH and ATP synthase activities, FATP2/FATP5, DGAT2, PPARα, SIRT1, UCP2 protein expressions, ACC and AMPK phosphorylation and PGC1α deacetylation. Resveratrol reduced triacylglycerols compared with the controls, although this reduction was lower than that induced by energy restriction. The mechanisms of action were different. Both decreased protein expression of fatty acid transporters, thus suggesting reduced fatty acid uptake from blood stream and liver triacylglycerol delivery, but only energy restriction reduced the assembly. These results show that resveratrol is useful for liver steatosis treatment within a balanced diet, although its effectiveness is lower than that of energy restriction. However, resveratrol is unable to increase the reduction in triacylglycerol content induced by energy restriction. PMID:28696376

Experimentally induced thyrotoxicosis leads to increased connectivity in temporal lobe structures: a resting state fMRI study.

PubMed

Göttlich, Martin; Heldmann, Marcus; Göbel, Anna; Dirk, Anna-Luise; Brabant, Georg; Münte, Thomas F

2015-06-01

Adult onset hyperthyroidism may impact on different cognitive domains, including attention and concentration, memory, perceptual function, language and executive function. Previous PET studies implicated changed functionality of limbic regions, the temporal and frontal lobes in hyperthyroidism, whereas it is unknown whether cognitive effects of hyperthyroidism may be due to changed brain connectivity. This study aimed to investigate the effect of experimentally induced short-term hyperthyroidism thyrotoxicosis on resting-state functional connectivity using functional magnetic resonance imaging. Twenty-nine healthy male right-handed subjects were examined twice, once prior and once after 8 weeks of oral administration of 250 μg levothyroxine per day. Resting-state fMRI was subjected to graph-theory based analysis methods to investigate whole-brain intrinsic functional connectivity. Despite a lack of subjective changes noticed by the subjects significant thyrotoxicosis was confirmed in all subjects. This induced a significant increase in resting-state functional connectivity specifically in the rostral temporal lobes (0.05 FDR corrected at the cluster level), which is caused by an increased connectivity to the cognitive control network. The increased connectivity between temporal poles and the cognitive control network shown here under experimental conditions supports an important function of thyroid hormones in the regulation of paralimbic structures. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cytoplasmic remodeling of erythrocyte raft lipids during infection by the human malaria parasite Plasmodium falciparum

PubMed Central

Murphy, Sean C.; Fernandez-Pol, Sebastian; Chung, Paul H.; Prasanna Murthy, S. N.; Milne, Stephen B.; Salomao, Marcela; Brown, H. Alex; Lomasney, Jon W.; Mohandas, Narla

2007-01-01

Studies of detergent-resistant membrane (DRM) rafts in mature erythrocytes have facilitated identification of proteins that regulate formation of endovacuolar structures such as the parasitophorous vacuolar membrane (PVM) induced by the malaria parasite Plasmodium falciparum. However, analyses of raft lipids have remained elusive because detergents interfere with lipid detection. Here, we use primaquine to perturb the erythrocyte membrane and induce detergent-free buoyant vesicles, which are enriched in cholesterol and major raft proteins flotillin and stomatin and contain low levels of cytoskeleton, all characteristics of raft microdomains. Lipid mass spectrometry revealed that phosphatidylethanolamine and phosphatidylglycerol are depleted in endovesicles while phosphoinositides are highly enriched, suggesting raft-based endovesiculation can be achieved by simple (non–receptor-mediated) mechanical perturbation of the erythrocyte plasma membrane and results in sorting of inner leaflet phospholipids. Live-cell imaging of lipid-specific protein probes showed that phosphatidylinositol (4,5) bisphosphate (PIP2) is highly concentrated in primaquine-induced vesicles, confirming that it is an erythrocyte raft lipid. However, the malarial PVM lacks PIP2, although another raft lipid, phosphatidylserine, is readily detected. Thus, different remodeling/sorting of cytoplasmic raft phospholipids may occur in distinct endovacuoles. Importantly, erythrocyte raft lipids recruited to the invasion junction by mechanical stimulation may be remodeled by the malaria parasite to establish blood-stage infection. PMID:17526861

Methotrexate diethyl ester-loaded lipid-core nanocapsules in aqueous solution increased antineoplastic effects in resistant breast cancer cell line.

PubMed

Yurgel, Virginia C; Oliveira, Catiuscia P; Begnini, Karine R; Schultze, Eduarda; Thurow, Helena S; Leon, Priscila M M; Dellagostin, Odir A; Campos, Vinicius F; Beck, Ruy C R; Guterres, Silvia S; Collares, Tiago; Pohlmann, Adriana R; Seixas, Fabiana K

2014-01-01

Breast cancer is the most frequent cancer affecting women. Methotrexate (MTX) is an antimetabolic drug that remains important in the treatment of breast cancer. Its efficacy is compromised by resistance in cancer cells that occurs through a variety of mechanisms. This study evaluated apoptotic cell death and cell cycle arrest induced by an MTX derivative (MTX diethyl ester [MTX(OEt)2]) and MTX(OEt)2-loaded lipid-core nanocapsules in two MTX-resistant breast adenocarcinoma cell lines, MCF-7 and MDA-MB-231. The formulations prepared presented adequate granulometric profile. The treatment responses were evaluated through flow cytometry. Relying on the mechanism of resistance, we observed different responses between cell lines. For MCF-7 cells, MTX(OEt)2 solution and MTX(OEt)2-loaded lipid-core nanocapsules presented significantly higher apoptotic rates than untreated cells and cells incubated with unloaded lipid-core nanocapsules. For MDA-MB-231 cells, MTX(OEt)2-loaded lipid-core nanocapsules were significantly more efficient in inducing apoptosis than the solution of the free drug. S-phase cell cycle arrest was induced only by MTX(OEt)2 solution. The drug nanoencapsulation improved apoptosis induction for the cell line that presents MTX resistance by lack of transport receptors.

Methotrexate diethyl ester-loaded lipid-core nanocapsules in aqueous solution increased antineoplastic effects in resistant breast cancer cell line

PubMed Central

Yurgel, Virginia C; Oliveira, Catiuscia P; Begnini, Karine R; Schultze, Eduarda; Thurow, Helena S; Leon, Priscila MM; Dellagostin, Odir A; Campos, Vinicius F; Beck, Ruy CR; Guterres, Silvia S; Collares, Tiago; Pohlmann, Adriana R; Seixas, Fabiana K

2014-01-01

Breast cancer is the most frequent cancer affecting women. Methotrexate (MTX) is an antimetabolic drug that remains important in the treatment of breast cancer. Its efficacy is compromised by resistance in cancer cells that occurs through a variety of mechanisms. This study evaluated apoptotic cell death and cell cycle arrest induced by an MTX derivative (MTX diethyl ester [MTX(OEt)2]) and MTX(OEt)2-loaded lipid-core nanocapsules in two MTX-resistant breast adenocarcinoma cell lines, MCF-7 and MDA-MB-231. The formulations prepared presented adequate granulometric profile. The treatment responses were evaluated through flow cytometry. Relying on the mechanism of resistance, we observed different responses between cell lines. For MCF-7 cells, MTX(OEt)2 solution and MTX(OEt)2-loaded lipid-core nanocapsules presented significantly higher apoptotic rates than untreated cells and cells incubated with unloaded lipid-core nanocapsules. For MDA-MB-231 cells, MTX(OEt)2-loaded lipid-core nanocapsules were significantly more efficient in inducing apoptosis than the solution of the free drug. S-phase cell cycle arrest was induced only by MTX(OEt)2 solution. The drug nanoencapsulation improved apoptosis induction for the cell line that presents MTX resistance by lack of transport receptors. PMID:24741306

Drug-induced liver injury: present and future

PubMed Central

Suk, Ki Tae

2012-01-01

Liver injury due to prescription and nonprescription medications is a growing medical, scientific, and public health problem. Worldwide, the estimated annual incidence rate of drug-induced liver injury (DILI) is 13.9-24.0 per 100,000 inhabitants. DILI is one of the leading causes of acute liver failure in the US. In Korea, the annual extrapolated incidence of cases hospitalized at university hospital is 12/100,000 persons/year. Most cases of DILI are the result of idiosyncratic metabolic responses or unexpected reactions to medication. There is marked geographic variation in relevant agents; antibiotics, anticonvulsants, and psychotropic drugs are the most common offending agents in the West, whereas in Asia, 'herbs' and 'health foods or dietary supplements' are more common. Different medical circumstances also cause discrepancy in definition and classification of DILI between West and Asia. In the concern of causality assessment, the application of the Roussel Uclaf Causality Assessment Method (RUCAM) scale frequently undercounts the cases caused by 'herbs' due to a lack of previous information and incompatible time criteria. Therefore, a more objective and reproducible tool that could be used for the diagnosis of DILI caused by 'herbs' is needed in Asia. In addition, a reporting system similar to the Drug-Induced Liver Injury Network (DILIN) in the US should be established as soon as possible in Asia. PMID:23091804

Ultrafast energy- and momentum-resolved dynamics of magnetic correlations in the photo-doped Mott insulator Sr 2IrO 4

DOE PAGES

Dean, M. P. M.; Cao, Y.; Liu, X.; ...

2016-05-09

Measuring how the magnetic correlations evolve in doped Mott insulators has greatly improved our understanding of the pseudogap, non-Fermi liquids and high-temperature superconductivity 1, 2, 3, 4. Recently, photo-excitation has been used to induce similarly exotic states transiently 5, 6, 7. However, the lack of available probes of magnetic correlations in the time domain hinders our understanding of these photo-induced states and how they could be controlled. Here, we implement magnetic resonant inelastic X-ray scattering at a free-electron laser to directly determine the magnetic dynamics after photo-doping the Mott insulator Sr 2IrO 4. We find that the non-equilibrium state, 2more » ps after the excitation, exhibits strongly suppressed long-range magnetic order, but hosts photo-carriers that induce strong, non-thermal magnetic correlations. These two-dimensional (2D) in-plane Néel correlations recover within a few picoseconds, whereas the three-dimensional (3D) long-range magnetic order restores on a fluence-dependent timescale of a few hundred picoseconds. In conclusion, the marked difference in these two timescales implies that the dimensionality of magnetic correlations is vital for our understanding of ultrafast magnetic dynamics.« less

Dietary Propolis Ameliorates Dextran Sulfate Sodium-Induced Colitis and Modulates the Gut Microbiota in Rats Fed a Western Diet.

PubMed

Wang, Kai; Jin, Xiaolu; You, Mengmeng; Tian, Wenli; Le Leu, Richard K; Topping, David L; Conlon, Michael A; Wu, Liming; Hu, Fuliang

2017-08-14

Propolis is an important hive product and considered beneficial to health. However, evidence of its potential for improving gut health is still lacking. Here we use rats to examine whether dietary supplementation with propolis could be used as a therapy for ulcerative colitis. Rats were fed with a Western style diet alone (controls) or supplemented with different amounts of Chinese propolis (0.1%, 0.2%, and 0.3%) to examine effects on acute colitis induced by 3% dextran sulphate sodium (DSS) in drinking water. Propolis at 0.3%, but not lower levels, significantly improved colitis symptoms compared with the control group, with a less pronounced disease activity index (DAI) ( p < 0.001), a significant increase in colon length/weight ratio ( p < 0.05) and an improved distal colon tissue structure as assessed by histology. Although short chain fatty acid levels in digesta were not altered by propolis supplementation, 16S rRNA phylogenetic sequencing revealed a significant increase in gut microbial diversity after 21 days of 0.3% propolis supplementation compared with controls including a significant increase in bacteria belonging to the Proteobacteria and Acidobacteria phyla. This is the first study to demonstrate that propolis can attenuate DSS-induced colitis and provides new insight into diet-microbiota interactions during inflammatory bowel disease.

The interactive roles of zinc and calcium in mitochondrial dysfunction and neurodegeneration.

PubMed

Pivovarova, Natalia B; Stanika, Ruslan I; Kazanina, Galina; Villanueva, Idalis; Andrews, S Brian

2014-02-01

Zinc has been implicated in neurodegeneration following ischemia. In analogy with calcium, zinc has been proposed to induce toxicity via mitochondrial dysfunction, but the relative role of each cation in mitochondrial damage remains unclear. Here, we report that under conditions mimicking ischemia in hippocampal neurons - normal (2 mM) calcium plus elevated (> 100 μM) exogenous zinc - mitochondrial dysfunction evoked by glutamate, kainate or direct depolarization is, despite significant zinc uptake, primarily governed by calcium. Thus, robust mitochondrial ion accumulation, swelling, depolarization, and reactive oxygen species generation were only observed after toxic stimulation in calcium-containing media. This contrasts with the lack of any mitochondrial response in zinc-containing but calcium-free medium, even though zinc uptake and toxicity were strong under these conditions. Indeed, abnormally high, ionophore-induced zinc uptake was necessary to elicit any mitochondrial depolarization. In calcium- and zinc-containing media, depolarization-induced zinc uptake facilitated cell death and enhanced accumulation of mitochondrial calcium, which localized to characteristic matrix precipitates. Some of these contained detectable amounts of zinc. Together these data indicate that zinc uptake is generally insufficient to trigger mitochondrial dysfunction, so that mechanism(s) of zinc toxicity must be different from that of calcium. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

Successfully resisting a pathogen is rarely costly in Daphnia magna

PubMed Central

2010-01-01

Background A central hypothesis in the evolutionary ecology of parasitism is that trade-offs exist between resistance to parasites and other fitness components such as fecundity, growth, survival, and predator avoidance, or resistance to other parasites. These trade-offs are called costs of resistance. These costs fall into two broad categories: constitutive costs of resistance, which arise from a negative genetic covariance between immunity and other fitness-related traits, and inducible costs of resistance, which are the physiological costs incurred by hosts when mounting an immune response. We sought to study inducible costs in depth using the crustacean Daphnia magna and its bacterial parasite Pasteuria ramosa. Results We designed specific experiments to study the costs induced by exposure to this parasite, and we re-analysed previously published data in an effort to determine the generality of such costs. However, despite the variety of genetic backgrounds of both hosts and parasites, and the different exposure protocols and environmental conditions used in these experiment, this work showed that costs of exposure can only rarely be detected in the D. magna-P. ramosa system. Conclusions We discuss possible reasons for this lack of detectable costs, including scenarios where costs of resistance to parasites might not play a major role in the co-evolution of hosts and parasites. PMID:21083915

Successfully resisting a pathogen is rarely costly in Daphnia magna.

PubMed

Labbé, Pierrick; Vale, Pedro F; Little, Tom J

2010-11-17

A central hypothesis in the evolutionary ecology of parasitism is that trade-offs exist between resistance to parasites and other fitness components such as fecundity, growth, survival, and predator avoidance, or resistance to other parasites. These trade-offs are called costs of resistance. These costs fall into two broad categories: constitutive costs of resistance, which arise from a negative genetic covariance between immunity and other fitness-related traits, and inducible costs of resistance, which are the physiological costs incurred by hosts when mounting an immune response. We sought to study inducible costs in depth using the crustacean Daphnia magna and its bacterial parasite Pasteuria ramosa. We designed specific experiments to study the costs induced by exposure to this parasite, and we re-analysed previously published data in an effort to determine the generality of such costs. However, despite the variety of genetic backgrounds of both hosts and parasites, and the different exposure protocols and environmental conditions used in these experiment, this work showed that costs of exposure can only rarely be detected in the D. magna-P. ramosa system. We discuss possible reasons for this lack of detectable costs, including scenarios where costs of resistance to parasites might not play a major role in the co-evolution of hosts and parasites.

Lack of Additive Effects of Resveratrol and Energy Restriction in the Treatment of Hepatic Steatosis in Rats.

PubMed

Milton-Laskibar, Iñaki; Aguirre, Leixuri; Fernández-Quintela, Alfredo; Rolo, Anabela P; Soeiro Teodoro, João; Palmeira, Carlos M; Portillo, María P

2017-07-11

The aims of the present study were to analyze the effect of resveratrol on liver steatosis in obese rats, to compare the effects induced by resveratrol and energy restriction and to research potential additive effects. Rats were initially fed a high-fat high-sucrose diet for six weeks and then allocated in four experimental groups fed a standard diet: a control group, a resveratrol-treated group, an energy restricted group and a group submitted to energy restriction and treated with resveratrol. We measured liver triacylglycerols, transaminases, FAS, MTP, CPT1a, CS, COX, SDH and ATP synthase activities, FATP2/FATP5, DGAT2, PPARα, SIRT1, UCP2 protein expressions, ACC and AMPK phosphorylation and PGC1α deacetylation. Resveratrol reduced triacylglycerols compared with the controls, although this reduction was lower than that induced by energy restriction. The mechanisms of action were different. Both decreased protein expression of fatty acid transporters, thus suggesting reduced fatty acid uptake from blood stream and liver triacylglycerol delivery, but only energy restriction reduced the assembly. These results show that resveratrol is useful for liver steatosis treatment within a balanced diet, although its effectiveness is lower than that of energy restriction. However, resveratrol is unable to increase the reduction in triacylglycerol content induced by energy restriction.

Green laser light activates the inner ear

NASA Astrophysics Data System (ADS)

Wenzel, Gentiana I.; Balster, Sven; Zhang, Kaiyin; Lim, Hubert H.; Reich, Uta; Massow, Ole; Lubatschowski, Holger; Ertmer, Wolfgang; Lenarz, Thomas; Reuter, Guenter

2009-07-01

The hearing performance with conventional hearing aids and cochlear implants is dramatically reduced in noisy environments and for sounds more complex than speech (e. g. music), partially due to the lack of localized sensorineural activation across different frequency regions with these devices. Laser light can be focused in a controlled manner and may provide more localized activation of the inner ear, the cochlea. We sought to assess whether visible light with parameters that could induce an optoacoustic effect (532 nm, 10-ns pulses) would activate the cochlea. Auditory brainstem responses (ABRs) were recorded preoperatively in anesthetized guinea pigs to confirm normal hearing. After opening the bulla, a 50-μm core-diameter optical fiber was positioned in the round window niche and directed toward the basilar membrane. Optically induced ABRs (OABRs), similar in shape to those of acoustic stimulation, were elicited with single pulses. The OABR peaks increased with energy level (0.6 to 23 μJ/pulse) and remained consistent even after 30 minutes of continuous stimulation at 13 μJ, indicating minimal or no stimulation-induced damage within the cochlea. Our findings demonstrate that visible light can effectively and reliably activate the cochlea without any apparent damage. Further studies are in progress to investigate the frequency-specific nature and mechanism of green light cochlear activation.

Impact of p53 status on heavy-ion radiation-induced micronuclei in circulating erythrocytes

NASA Technical Reports Server (NTRS)

Chang, P. Y.; Torous, D.; Lutze-Mann, L.; Winegar, R.

2000-01-01

Transgenic mice that differed in their p53 genetic status were exposed to an acute dose of highly charged and energetic (HZE) iron particle radiation. Micronuclei (MN) in two distinct populations of circulating peripheral blood erythrocytes, the immature reticulocytes (RETs) and the mature normochromatic erythrocytes (NCEs), were measured using a simple and efficient flow cytometric procedure. Our results show significant elevation in the frequency of micronucleated RETs (%MN-RETs) at 2 and 3 days post-radiation. At 3 days post-irradiation, the magnitude of the radiation-induced MN-RET was 2.3-fold higher in the irradiated p53 wild-type animals compared to the unirradiated controls, 2.5-fold higher in the p53 hemizygotes and 4.3-fold higher in the p53 nullizygotes. The persistence of this radiation-induced elevation of MN-RETs is dependent on the p53 genetic background of the animal. In the p53 wild-type and p53 hemizygotes, %MN-RETs returned to control levels by 9 days post-radiation. However, elevated levels of %MN-RETs in p53 nullizygous mice persisted beyond 56 days post-radiation. We also observed elevated MN-NCEs in the peripheral circulation after radiation, but the changes in radiation-induced levels of MN-NCEs appear dampened compared to those of the MN-RETs for all three strains of animals. These results suggest that the lack of p53 gene function may play a role in the iron particle radiation-induced genomic instability in stem cell populations in the hematopoietic system.

Rapid generation of mitochondrial superoxide induces mitochondrion-dependent but caspase-independent cell death in hippocampal neuronal cells that morphologically resembles necroptosis☆

PubMed Central

Fukui, Masayuki; Choi, Hye Joung; Zhu, Bao Ting

2013-01-01

Studies in recent years have revealed that excess mitochondrial superoxide production is an important etiological factor in neurodegenerative diseases, resulting from oxidative modifications of cellular lipids, proteins, and nucleic acids. Hence, it is important to understand the mechanism by which mitochondrial oxidative stress causes neuronal death. In this study, the immortalized mouse hippocampal neuronal cells (HT22) in culture were used as a model and they were exposed to menadione (also known as vitamin K3) to increase intracellular superoxide production. We found that menadione causes preferential accumulation of superoxide in the mitochondria of these cells, along with the rapid development of mitochondrial dysfunction and cellular ATP depletion. Neuronal death induced by menadione is independent of the activation of the MAPK signaling pathways and caspases. The lack of caspase activation is due to the rapid depletion of cellular ATP. It was observed that two ATP-independent mitochondrial nucleases, namely, AIF and Endo G, are released following menadione exposure. Silencing of their expression using specific siRNAs results in transient suppression (for ~12 h) of mitochondrial superoxide-induced neuronal death. While suppression of the mitochondrial superoxide dismutase expression markedly sensitizes neuronal cells to mitochondrial superoxide-induced cytotoxicity, its over-expression confers strong protection. Collectively, these findings showed that many of the observed features associated with mitochondrial superoxide-induced cell death, including caspase independency, rapid depletion of ATP level, mitochondrial release of AIF and Endo G, and mitochondrial swelling, are distinctly different from those of apoptosis; instead they resemble some of the known features of necroptosis. PMID:22575170

Pre-exposure to 50 Hz magnetic fields modifies menadione-induced genotoxic effects in human SH-SY5Y neuroblastoma cells.

PubMed

Luukkonen, Jukka; Liimatainen, Anu; Höytö, Anne; Juutilainen, Jukka; Naarala, Jonne

2011-03-23

Extremely low frequency (ELF) magnetic fields (MF) are generated by power lines and various electric appliances. They have been classified as possibly carcinogenic by the International Agency for Research on Cancer, but a mechanistic explanation for carcinogenic effects is lacking. A previous study in our laboratory showed that pre-exposure to ELF MF altered cancer-relevant cellular responses (cell cycle arrest, apoptosis) to menadione-induced DNA damage, but it did not include endpoints measuring actual genetic damage. In the present study, we examined whether pre-exposure to ELF MF affects chemically induced DNA damage level, DNA repair rate, or micronucleus frequency in human SH-SY5Y neuroblastoma cells. Exposure to 50 Hz MF was conducted at 100 µT for 24 hours, followed by chemical exposure for 3 hours. The chemicals used for inducing DNA damage and subsequent micronucleus formation were menadione and methyl methanesulphonate (MMS). Pre-treatment with MF enhanced menadione-induced DNA damage, DNA repair rate, and micronucleus formation in human SH-SY5Y neuroblastoma cells. Although the results with MMS indicated similar effects, the differences were not statistically significant. No effects were observed after MF exposure alone. The results confirm our previous findings showing that pre-exposure to MFs as low as 100 µT alters cellular responses to menadione, and show that increased genotoxicity results from such interaction. The present findings also indicate that complementary data at several chronological points may be critical for understanding the MF effects on DNA damage, repair, and post-repair integrity of the genome.

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.

Effects produced by different types of laser in cornea of Guinea pigs: Identification of a laser capable of producing superficial lesions without leaving scars.

PubMed

Suárez, A C; Suárez, M F; Crim, N; Monti, R; Urrets-Zavalía, J A; Serra, H M

2015-10-01

Climatic droplets keratopathy (CDK) is closely associated with superficial corneal erosions and lack of protective mechanisms against the harmful effects of ultraviolet radiation (UVR) during a prolonged period of time. One of the difficulties in studying the pathogenic mechanisms involved in this human disease is the lack of an experimental animal model. In this paper, a study is conducted on the effects of 4 types of lasers at various powers and time conditions on the normal guinea pig corneas in order to select only one laser condition that reversibly injures the epithelium and superficial stroma, without leaving scarring. Damage was induced in the cornea of Guinea pigs using different powers and exposure times of 4 types of laser: argon, CO2, diode and Nd-Yag, and any injuries were evaluated by biomicroscopy (BM) and optical microscopy. Corneas from other normal animals were exposed to argon laser (350 mW, 0.3s, 50 μm of diameter), and the induced alterations were studied at different times using BM, optical coherence tomography (OCT) and transmission electron microscopy (TEM). Only argon laser at 350 mW, 0.3s, 50 μm of diameter produced epithelium and superficial stroma lesions. Some leukomas were observed by BM, and they disappeared by day 15. Corneal thickness measured by OCT decreased in the eyes treated with argon laser during the first week. Using TEM, different ultra structural alterations in corneal epithelium and stroma were observed during the early days, which disappeared by day 15. It was possible to develop reproducible corneal epithelium and anterior stroma injuries using Argon laser at 350 mW, 0.3s, 50 μm of diameter. In vivo and in vitro studies showed that injured corneas with these laser conditions did not leave irreversible microscopic or ultra structural alterations. This protocol of corneal erosion combined with exposure to UVR and partial deficiency of ascorbate in the diets of the animals for an extended period of time has been used in order to try to develop an experimental model of CDK. Copyright © 2014 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

Expression of a bacterial catalase in a strictly anaerobic methanogen significantly increases tolerance to hydrogen peroxide but not oxygen

PubMed Central

Jennings, Matthew E.; Schaff, Cody W.; Horne, Alexandra J.; Lessner, Faith H.

2014-01-01

Haem-dependent catalase is an antioxidant enzyme that degrades H2O2, producing H2O and O2, and is common in aerobes. Catalase is present in some strictly anaerobic methane-producing archaea (methanogens), but the importance of catalase to the antioxidant system of methanogens is poorly understood. We report here that a survey of the sequenced genomes of methanogens revealed that the majority of species lack genes encoding catalase. Moreover, Methanosarcina acetivorans is a methanogen capable of synthesizing haem and encodes haem-dependent catalase in its genome; yet, Methanosarcina acetivorans cells lack detectable catalase activity. However, inducible expression of the haem-dependent catalase from Escherichia coli (EcKatG) in the chromosome of Methanosarcina acetivorans resulted in a 100-fold increase in the endogenous catalase activity compared with uninduced cells. The increased catalase activity conferred a 10-fold increase in the resistance of EcKatG-induced cells to H2O2 compared with uninduced cells. The EcKatG-induced cells were also able to grow when exposed to levels of H2O2 that inhibited or killed uninduced cells. However, despite the significant increase in catalase activity, growth studies revealed that EcKatG-induced cells did not exhibit increased tolerance to O2 compared with uninduced cells. These results support the lack of catalase in the majority of methanogens, since methanogens are more likely to encounter O2 rather than high concentrations of H2O2 in the natural environment. Catalase appears to be a minor component of the antioxidant system in methanogens, even those that are aerotolerant, including Methanosarcina acetivorans. Importantly, the experimental approach used here demonstrated the feasibility of engineering beneficial traits, such as H2O2 tolerance, in methanogens. PMID:24222618

Trans -cyclopropanation of mycolic acids on trehalose dimycolate suppresses Mycobacterium tuberculosis –induced inflammation and virulence

PubMed Central

Rao, Vivek; Gao, Feng; Chen, Bing; Jacobs, William R.; Glickman, Michael S.

2006-01-01

Recent studies have shown that fine structural modifications of Mycobacterium tuberculosis cell envelope lipids mediate host cell immune activation during infection. One such alteration in lipid structure is cis-cyclopropane modification of the mycolic acids on trehalose dimycolate (TDM) mediated by proximal cyclopropane synthase of α mycolates (pcaA), a proinflammatory lipid modification during early infection. Here we examine the pathogenetic role and immunomodulatory function of mycolic acid cyclopropane stereochemistry by characterizing an M. tuberculosis cyclopropane–mycolic acid synthase 2 (cmaA2) null mutant (ΔcmaA2) that lacks trans-cyclopropanation of mycolic acids. Although titers of WT and ΔcmaA2 organisms were identical during mouse infection, ΔcmaA2 bacteria were hypervirulent while inducing larger granulomas than WT M. tuberculosis. The hypervirulence of the ΔcmaA2 strain depended on host TNF-α and IFN-γ. Loss of trans-cyclopropanation enhanced M. tuberculosis–induced macrophage inflammatory responses, a phenotype that was transferable with petroleum ether extractable lipids. Finally, purified TDM lacking trans-cyclopropane rings was 5-fold more potent in stimulating macrophages. These results establish cmaA2-dependent trans-cyclopropanation of TDM as a suppressor of M. tuberculosis–induced inflammation and virulence. In addition, cyclopropane stereochemistries on mycolic acids interact directly with host cells to both positively and negatively influence host innate immune activation. PMID:16741578

Occludin confers adhesiveness when expressed in fibroblasts.

PubMed

Van Itallie, C M; Anderson, J M

1997-05-01

Occludin is an integral membrane protein specifically associated with tight junctions. Previous studies suggest it is likely to function in forming the intercellular seal. In the present study, we expressed occludin under an inducible promotor in occludin-null fibroblasts to determine whether this protein confers intercellular adhesion. When human occludin is stably expressed in NRK and Rat-1 fibroblasts, which lack endogenous occludin and tight junctions but do have well developed ZO-1-containing adherens-like junctions, occludin colocalizes with ZO-1 to points of cell-cell contact. In contrast, L-cell fibroblasts which lack cadherin-based adherens junctions, target neither ZO-1 nor occludin to sites of cell contact. Occludin-induced adhesion was next quantified using a suspended cell assay. In NRK and Rat-1 cells, occludin expression induces adhesion in the absence of calcium, thus independent of cadherin-cadherin contacts. In contrast, L-cells are nonadhesive in this assay and show no increase in adhesion after induction of occludin expression. Binding of an antibody to the first of the putative extracellular loops of occludin confirmed that this sequence was exposed on the cell surface, and synthetic peptides containing the amino acid sequence of this loop inhibit adhesion induced by occludin expression. These results suggest that the extracellular surface of occludin is directly involved in cell-cell adhesion and the ability to confer adhesiveness correlates with the ability to colocalize with its cytoplasmic binding protein, ZO-1.

A novel podocyte gene, semaphorin 3G, protects glomerular podocyte from lipopolysaccharide-induced inflammation.

PubMed

Ishibashi, Ryoichi; Takemoto, Minoru; Akimoto, Yoshihiro; Ishikawa, Takahiro; He, Peng; Maezawa, Yoshiro; Sakamoto, Kenichi; Tsurutani, Yuya; Ide, Shintaro; Ide, Kana; Kawamura, Harukiyo; Kobayashi, Kazuki; Tokuyama, Hirotake; Tryggvason, Karl; Betsholtz, Christer; Yokote, Koutaro

2016-05-16

Kidney diseases including diabetic nephropathy have become huge medical problems, although its precise mechanisms are still far from understood. In order to increase our knowledge about the patho-physiology of kidney, we have previously identified >300 kidney glomerulus-enriched transcripts through large-scale sequencing and microarray profiling of the mouse glomerular transcriptome. One of the glomerulus-specific transcripts identified was semaphorin 3G (Sema3G) which belongs to the semaphorin family. The aim of this study was to analyze both the in vivo and in vitro functions of Sema3G in the kidney. Sema3G was expressed in glomerular podocytes. Although Sema3G knockout mice did not show obvious glomerular defects, ultrastructural analyses revealed partially aberrant podocyte foot processes structures. When these mice were injected with lipopolysaccharide to induce acute inflammation or streptozotocin to induce diabetes, the lack of Sema3G resulted in increased albuminuria. The lack of Sema3G in podocytes also enhanced the expression of inflammatory cytokines including chemokine ligand 2 and interleukin 6. On the other hand, the presence of Sema3G attenuated their expression through the inhibition of lipopolysaccharide-induced Toll like receptor 4 signaling. Taken together, our results surmise that the Sema3G protein is secreted by podocytes and protects podocytes from inflammatory kidney diseases and diabetic nephropathy.

A novel podocyte gene, semaphorin 3G, protects glomerular podocyte from lipopolysaccharide-induced inflammation

PubMed Central

Ishibashi, Ryoichi; Takemoto, Minoru; Akimoto, Yoshihiro; Ishikawa, Takahiro; He, Peng; Maezawa, Yoshiro; Sakamoto, Kenichi; Tsurutani, Yuya; Ide, Shintaro; Ide, Kana; Kawamura, Harukiyo; Kobayashi, Kazuki; Tokuyama, Hirotake; Tryggvason, Karl; Betsholtz, Christer; Yokote, Koutaro

2016-01-01

Kidney diseases including diabetic nephropathy have become huge medical problems, although its precise mechanisms are still far from understood. In order to increase our knowledge about the patho-physiology of kidney, we have previously identified >300 kidney glomerulus-enriched transcripts through large-scale sequencing and microarray profiling of the mouse glomerular transcriptome. One of the glomerulus-specific transcripts identified was semaphorin 3G (Sema3G) which belongs to the semaphorin family. The aim of this study was to analyze both the in vivo and in vitro functions of Sema3G in the kidney. Sema3G was expressed in glomerular podocytes. Although Sema3G knockout mice did not show obvious glomerular defects, ultrastructural analyses revealed partially aberrant podocyte foot processes structures. When these mice were injected with lipopolysaccharide to induce acute inflammation or streptozotocin to induce diabetes, the lack of Sema3G resulted in increased albuminuria. The lack of Sema3G in podocytes also enhanced the expression of inflammatory cytokines including chemokine ligand 2 and interleukin 6. On the other hand, the presence of Sema3G attenuated their expression through the inhibition of lipopolysaccharide-induced Toll like receptor 4 signaling. Taken together, our results surmise that the Sema3G protein is secreted by podocytes and protects podocytes from inflammatory kidney diseases and diabetic nephropathy. PMID:27180624

Menadione triggers cell death through ROS-dependent mechanisms involving PARP activation without requiring apoptosis.

PubMed

Loor, Gabriel; Kondapalli, Jyothisri; Schriewer, Jacqueline M; Chandel, Navdeep S; Vanden Hoek, Terry L; Schumacker, Paul T

2010-12-15

Low levels of reactive oxygen species (ROS) can function as redox-active signaling messengers, whereas high levels of ROS induce cellular damage. Menadione generates ROS through redox cycling, and high concentrations trigger cell death. Previous work suggests that menadione triggers cytochrome c release from mitochondria, whereas other studies implicate the activation of the mitochondrial permeability transition pore as the mediator of cell death. We investigated menadione-induced cell death in genetically modified cells lacking specific death-associated proteins. In cardiomyocytes, oxidant stress was assessed using the redox sensor RoGFP, expressed in the cytosol or the mitochondrial matrix. Menadione elicited rapid oxidation in both compartments, whereas it decreased mitochondrial potential and triggered cytochrome c redistribution to the cytosol. Cell death was attenuated by N-acetylcysteine and exogenous glutathione or by overexpression of cytosolic or mitochondria-targeted catalase. By contrast, no protection was observed in cells overexpressing Cu,Zn-SOD or Mn-SOD. Overexpression of antiapoptotic Bcl-X(L) protected against staurosporine-induced cell death, but it failed to confer protection against menadione. Genetic deletion of Bax and Bak, cytochrome c, cyclophilin D, or caspase-9 conferred no protection against menadione-induced cell death. However, cells lacking PARP-1 showed a significant decrease in menadione-induced cell death. Thus, menadione induces cell death through the generation of oxidant stress in multiple subcellular compartments, yet cytochrome c, Bax/Bak, caspase-9, and cyclophilin D are dispensable for cell death in this model. These studies suggest that multiple redundant cell death pathways are activated by menadione, but that PARP plays an essential role in mediating each of them. Copyright © 2010 Elsevier Inc. All rights reserved.

Menadione triggers cell death through ROS-dependent mechanisms involving PARP activation without requiring apoptosis

PubMed Central

Loor, Gabriel; Kondapalli, Jyothisri; Schriewer, Jacqueline M.; Chandel, Navdeep S.; Vanden Hoek, Terry L.; Schumacker, Paul T.

2010-01-01

Low levels of reactive oxygen species (ROS) can function as redox-active signaling messengers, whereas high levels of ROS induce cellular damage. Menadione generates ROS through redox cycling, and high concentrations trigger cell death. Previous work suggests that menadione triggers cytochrome c release from mitochondria, while other studies implicate activation of the mitochondrial permeability transition poreas the mediator of cell death. We investigated menadione-induced cell death in genetically modified cells lacking specific death-associated proteins. In cardiomyocytes, oxidant stress was assessed using the redox sensor RoGFP, expressed in the cytosol or the mitochondrial matrix. Menadione elicited rapid oxidation in both compartments, while it decreased mitochondrial potential and triggered cytochrome c redistribution to the cytosol. Cell death was attenuated by N-acetyl cysteine and exogenous glutathione (GSH), or by over-expression of cytosolic or mitochondria-targeted catalase. By contrast, no protection was observed in cells over-expressing Cu, Zn-SOD or MnSOD. Over-expression of antiapoptotic Bcl-XLprotected against staurosporine-induced cell death, but it failed to confer protection against menadione. Genetic deletion of Bax and Bak, cytochrome c, cyclophilin D or caspase-9 conferred no protection against menadione-induced cell death. However, cells lacking PARP-1 showed a significant decrease in menadione-induced cell death. Thus, menadione induces cell death through the generation of oxidant stress in multiple subcellular compartments, yet cytochromec, Bax/Bak, caspase-9 and cyclophilin D are dispensable for cell death in this model. These studies suggest that multiple redundant cell death pathways are activated by menadione, but that PARP plays an essential role in mediating each of them. PMID:20937380

Multidrug Resistance Protein 1 Deficiency Promotes Doxorubicin-Induced Ovarian Toxicity in Female Mice.

PubMed

Wang, Yingzheng; Liu, Mingjun; Zhang, Jiyang; Liu, Yuwen; Kopp, Megan; Zheng, Weiwei; Xiao, Shuo

2018-05-01

Multidrug resistance protein 1 (MDR1), a phase III drug transporter that exports substrates out of cells, has been discovered in both cancerous and normal tissues. The over expression of MDR1 in cancer cells contributes to multiple drug resistance, whereas the MDR1 in normal tissues protects them from chemical-induced toxicity. Currently, the role of MDR1 in the ovary has not been entirely understood. Our objective is to determine the function of MDR1 in protecting against chemotherapy-induced ovarian toxicity. Using both the in vivo transgenic mouse model and in vitro follicle culture model, we investigated the expression of MDR1 in the ovary, the effect of MDR1 deficiency on doxorubicin (DOX)-induced ovarian toxicity, and the ovarian steroid hormonal regulation of MDR1. Results showed that the MDR1 was expressed in the ovarian epithelial cells, stroma cells, theca cell layers, endothelial cells, and luteal cells. The lack of MDR1 did not affect female ovarian function and fertility; however, its deficiency significantly exacerbated the DOX-induced ovarian toxicity in both in vivo and in vitro models. The MDR1 showed significantly higher expression levels in the ovaries at estrus and metestrus stages than those at proestrus and diestrus stages. However, this dynamic expression pattern was not regulated by the ovarian steroid hormones of estrogen (E2) and progesterone (P4) but correlated to the number and status of corpus luteum. In conclusion, our study demonstrates that the lack of MDR1 promotes DOX-induced ovarian toxicity, suggesting the critical role of MDR1 in protecting female ovarian functions during chemotherapy.

Informed herbivore movement and interplant communication determine the effects of induced resistance in an individual-based model.

PubMed

Rubin, Ilan N; Ellner, Stephen P; Kessler, André; Morrell, Kimberly A

2015-09-01

1. Plant induced resistance to herbivory affects the spatial distribution of herbivores, as well as their performance. In recent years, theories regarding the benefit to plants of induced resistance have shifted from ideas of optimal resource allocation towards a more eclectic set of theories that consider spatial and temporal plant variability and the spatial distribution of herbivores among plants. However, consensus is lacking on whether induced resistance causes increased herbivore aggregation or increased evenness, as both trends have been experimentally documented. 2. We created a spatial individual-based model that can describe many plant-herbivore systems with induced resistance, in order to analyse how different aspects of induced resistance might affect herbivore distribution, and the total damage to a plant population, during a growing season. 3. We analyse the specific effects on herbivore aggregation of informed herbivore movement (preferential movement to less-damaged plants) and of information transfer between plants about herbivore attacks, in order to identify mechanisms driving both aggregation and evenness. We also investigate how the resulting herbivore distributions affect the total damage to plants and aggregation of damage. 4. Even, random and aggregated herbivore distributions can all occur in our model with induced resistance. Highest levels of aggregation occurred in the models with informed herbivore movement, and the most even distributions occurred when the average number of herbivores per plant was low. With constitutive resistance, only random distributions occur. Damage to plants was spatially correlated, unless plants recover very quickly from damage; herbivore spatial autocorrelation was always weak. 5. Our model and results provide a simple explanation for the apparent conflict between experimental results, indicating that both increased aggregation and increased evenness of herbivores can result from induced resistance. We demonstrate that information transfer from plants to herbivores, and from plants to neighbouring plants, can both be major factors in determining non-random herbivore distributions. © 2015 The Authors. Journal of Animal Ecology © 2015 British Ecological Society.

A novel Rieske-type protein derived from an apoptosis-inducing factor-like (AIFL) transcript with a retained intron 4 induces change in mitochondrial morphology and growth arrest

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

Murata, Yasuhiko, E-mail: 97318@ib.k.u-tokyo.ac.jp; Furuyama, Isao; Oda, Shoji

2011-04-01

Highlights: {yields} A novel major transcript, AIFL-I4, is found. {yields} Nuclear localization of AIFL-I4 induces mitochondrial morphology change and suppression of cell proliferation. {yields} AIFL-I4 mutant with a lesion in [2Fe-2S] cluster binding site does not induce these phenotypes. {yields} [2Fe-2S] cluster binding site is essential for these phenotypes. -- Abstract: Apoptosis-inducing factor-like (AIFL) protein contains a Rieske domain and pyridine nucleotide-disulfide oxidoreductase (Pyr{sub r}edox) domain that shows 35% homology to that of apoptosis-inducing factor (AIF) protein. We identified a novel major transcript of the medaka (Oryzias latipes) AIFL gene that retained intron 4 (AIFL-I4) in embryos and tissues frommore » adult fish. The product of this transcript, AIFL-I4 protein, lacked the Pyr{sub r}edox domain because of a nonsense codon in intron 4. Both AIFL-I4 and full-length AIFL (fAIFL) transcripts were highly expressed in the brain and late embryos, and relative fAIFL and AIFL-I4 expression levels differed among tissues. Transient expression of AIFL-I4 and fAIFL tagged with GFP showed that AIFL-I4 localized in the nucleus, while fAIFL localized throughout the cytoplasm. We also found that overexpression of AIFL-I4 induced a change in mitochondrial morphology and suppression of cell proliferation. AIFL-I4 mutant with a lesion in [2Fe-2S] cluster binding site of the Rieske domain did not induce these phenotypes. This report is the first to demonstrate nuclear localization of a Rieske-type protein translated from the AIFL gene. Our data suggested that the [2Fe-2S] cluster binding site was essential for the nuclear localization and involved in mitochondrial morphology and suppression of cell proliferation.« less

Differential inhibition of rat and human Na+-dependent taurocholate cotransporting polypeptide (NTCP/SLC10A1)by bosentan: a mechanism for species differences in hepatotoxicity.

PubMed

Leslie, Elaine M; Watkins, Paul B; Kim, Richard B; Brouwer, Kim L R

2007-06-01

Bile acid accumulation in hepatocytes due to inhibition of the canalicular bile salt export pump (BSEP/ABCB11) has been proposed as a mechanism for bosentan-induced hepatotoxicity. The observation that bosentan does not induce hepatotoxicity in rats, although bosentan has been reported to inhibit rat Bsep and cause elevated serum bile acids, challenges this mechanism. The lack of hepatotoxicity could be explained if bosentan inhibited hepatocyte uptake as well as canalicular efflux of bile acids. In the current study, bosentan was found to be a more potent inhibitor of Na(+)-dependent taurocholate uptake in rat (IC(50) 5.4 microM) than human (IC(50) 30 microM) suspended hepatocytes. In addition, bosentan was a more potent inhibitor of taurocholate uptake by rat Na(+)-dependent taurocholate co-transporting polypeptide (Ntcp/Slc10a1) (IC(50) 0.71 microM) than human NTCP (SLC10A1) (IC(50) 24 microM) expressed in HEK293 cells. Thus, bosentan is a more potent inhibitor of Ntcp than NTCP, and this should result in less intrahepatocyte accumulation of bile acids in rats during bosentan treatment. To begin characterization of this species difference, two chimeric molecules were generated and expressed in HEK293 cells; NTCP(1-140)/Ntcp(141-362) and Ntcp(1-140)/NTCP(141-349). The mode of bosentan inhibition was noncompetitive for Ntcp, and competitive for NTCP (K(i) 18 microM) and NTCP(1-140)/Ntcp(141-362) (K(i) 1.7 microM); bosentan affected both the K(m) and V(max) of Ntcp(1-140)/NTCP(141-349) (K(i) 7.0 microM). The carboxyl portions of NTCP and Ntcp were found to confer species differences in basal taurocholate transport V(max). In conclusion, differential inhibition of Ntcp and NTCP may represent a novel mechanism for species differences in bosentan-induced hepatotoxicity.

Changes in Mood States Are Induced by Smelling Familiar and Exotic Fragrances

PubMed Central

Sarid, Orly; Zaccai, Michele

2016-01-01

Familiar fragrances usually induce positive mood states and elicit favorable evaluation. Relaxation is also widely thought to improve mood state. Yet experimental evidence on the effect of two different stimuli, fragrance smelling and breathing relaxation, on mood state, and fragrance evaluation is lacking. This study aimed to test (1) the effect of two familiar fragrances, lavender and myrtle, and two exotic fragrances, bergamot and ravensara, on perceived mood states before and after relaxation, (2) the effect of relaxation on perceived mood states for each fragrance, and (3) the effect of relaxation on fragrance evaluation as defined by adjectives. We hypothesized that mood states and assessment of the fragrances would differently be affected both in familiar vs. non-familiar fragrances and also before and after relaxation. Participants (n = 127) completed questionnaires on their mood states at baseline (T0). They were then presented with each of the four fragrances separately and asked to report on mood state and to assess the fragrances with adjectives before (T1) and after (T2) breathing relaxation. Analyses of the T0–T1 delta values of mood states by ANOVA repeated measures and post hoc comparisons showed that mood states were affected by fragrance smelling with no clear differences observed between familiar and exotic fragrances. The same analyses of T1–T2 values showed no differences in mood state after breathing relaxation and fragrance smelling. Fragrance assessment by adjectives indicated a non-conclusive trend for familiar and exotic fragrances. In sum, mood states induced by the fragrance smelling stimulus (T0–T1) were not changed by the addition of the second stimulus of relaxation (T1–T2), indicating that the former stimulus was stronger than the latter. On the other hand, the cognitive component represented by adjective-based assessment of fragrances was slightly modified by the relaxation stimulus. PMID:27877148

Upper trapezius relaxation induced by TENS and interferential current in computer users with chronic nonspecific neck discomfort: An electromyographic analysis.

PubMed

Acedo, Adriano Alexandre; Luduvice Antunes, Ana Carolina; Barros dos Santos, André; Barbosa de Olveira, Cintia; Tavares dos Santos, Claudia; Colonezi, Gustavo Lacreta Toledo; Fontana, Felipe Antonio Medeiros; Fukuda, Thiago Yukio

2015-01-01

Recent studies have shown that a transcutaneous electrical nerve stimulation (TENS) and interferential current (IFC) application reduces pain in subjects with musculoskeletal disorders. However there are no clinical trials evaluating or comparing the muscle relaxation generated for these devices. To compare the muscle relaxation of the upper trapezius induced by the application of TENS and IFC in females with chronic nonspecific neck discomfort. Sixty-four females between 18 and 40 years of age and a history of nonspecific neck discomfort were randomly assigned to a TENS or an IFC group. The women in the TENS (N = 32; mean age 22 years) and IFC (N = 32, mean age 23 years) group were submitted to current application during 3 consecutive days and were assessed by electromyography (EMG) in different times aiming to quantify the muscular tension of the upper trapezius. A visual analogue scale (VAS) was used as pain measure at baseline (before TENS or IFC application) and at the end of the study. At baseline, demographic, pain, and EMG assessment data were similar between groups. Those in the IFC group had a significant trapezius relaxation after 3 IFC applications when compared to baseline and intermediate evaluations (P < 0.05). In contrast, the same analysis showed no significant difference between all assessments in the TENS group (P >0.05). In relation to pain relief, both groups showed an improvement at the end of the study when compared to baseline (both,P <0.05). The between-group analysis showed no difference for the subjects who received such IFC as TENS application (P <0.05). IFC induced the upper trapezius relaxation after 3 sessions in females with neck discomfort, but the TENS application did not change the muscular tension. However, these results should be carefully interpreted due to the lack of differences between groups. A significant pain decrease was found in the subjects of both groups, however, only the IFC application presented a clinically important improvement.

A new animal diet based on human Western diet is a robust diet-induced obesity model: comparison to high-fat and cafeteria diets in term of metabolic and gut microbiota disruption.

PubMed

Bortolin, R C; Vargas, A R; Gasparotto, J; Chaves, P R; Schnorr, C E; Martinello, Kd B; Silveira, A K; Rabelo, T K; Gelain, D P; Moreira, J C F

2018-03-01

Obesity is a metabolic disorder that predisposes patients to numerous diseases and has become a major global public-health concern. Animal models of diet-induced obesity (DIO) are frequently used to study obesity, but which DIO model most accurately reflects the pathology of human obesity remains unclear. In this study, we designed a diet based on the human Western diet (WD) and compared it with the cafeteria diet (CAF) and high-fat diet (HFD) in order to evaluate which diet most closely mirrors human obesity. Wistar rats were fed four different diets (WD, CAF, HFD and a low-fat diet) for 18 weeks. Metabolic parameters and gut microbiota changes were then characterized. Rats fed the four different diets exhibited completely different phenotypes, highlighting the importance of diet selection. This study also revealed that WD most effectively induced obesity and obesity-related disorders, and thus proved to be a robust model of human obesity. Moreover, WD-fed rats developed obesity and obesity-related comorbidities independent of major alterations in gut microbiota composition (dysbiosis), whereas CAF-fed rats developed the greatest dysbiosis independent of obesity. We also characterized gut microbiota after feeding on these four different diets and identified five genera that might be involved in the pathogenesis of obesity. These data suggest that diet, and not the obese state, was the major driving force behind gut microbiota changes. Moreover, the marked dysbiosis observed in CAF-fed rats might have resulted from the presence of several additives present in the CAF diet, or even a lack of essential vitamins and minerals. Based on our findings, we recommend the use of the prototypic WD (designed here) in DIO models. Conversely, CAF could be used to investigate the effects of excessive consumption of industrially produced and highly processed foods, which are characteristic of Western society.

Three outer arm dynein heavy chains of Chlamydomonas reinhardtii operate in a coordinated fashion both in vitro and in vivo.

PubMed

Takazaki, Hiroko; Liu, Zhongmei; Jin, Mingyue; Kamiya, Ritsu; Yasunaga, Takuo

2010-07-01

Outer arm dynein (OAD) in cilia and flagella contains two to three nonidentical heavy chains (HCs) that possess motor activity. In Chlamydomonas, flagellar OAD contains three HCs, alpha-, beta-, and gamma-HCs, each appearing to have a distinct role. To determine the precise molecular mechanism of their function, cross-sectional electron micrographs of wild-type and single HC-disruption mutants were compared and statistically analyzed. While the alpha-HC mutant displayed an OAD of lower density, which was attributed to a lack of alpha-HC, the OAD of beta- and gamma-HC mutants not only lacked the corresponding HC, but was also significantly affected in its structure, particularly with respect to the localization of alpha-HC. The lack of beta-HC induced mislocalization of alpha-HC, while a disruption of the gamma-HC gene resulted in the synchronized movement of alpha-HC and beta-HC in the manners for stacking. Interestingly, using cryo-electron microscopy, purified OADs were typically observed consisting of two stacked heads and an independent single head, which presumably corresponded to gamma-HC. This conformation is different from previous reports in which the three HCs displayed a stacked form in flagella observed by cryo-electron tomography and a bouquet structure on mica in deep-etch replica images. These results suggest that gamma-HC supports the tight stacking arrangement of inter or intra alpha-/beta-HC to facilitate the proper functioning of OAD. 2010 Wiley-Liss, Inc.

Exposure to Air Pollution Enhances the Generation of Vascular Microparticles

EPA Science Inventory

Epidemiological studies associate exposure to ambient levels of particulate matter (PM) with cardiovascular morbidity and mortality. The biological mechanisms by which PM exposure induces cardiovascular effects remain to be elucidated. One important limitation is the lack of sens...

Novel quantitative methods for characterization of chemical induced functional alteration in developing neuronal cultures

EPA Science Inventory

ABSTRACT BODY: Thousands of chemicals lack adequate testing for adverse effects on nervous system development, stimulating research into alternative methods to screen chemicals for potential developmental neurotoxicity. Microelectrode arrays (MEA) collect action potential spiking...

Phenytoin-induced toxic epidermal necrolysis: Review and recommendations

PubMed Central

Al-Quteimat, Osama M.

2016-01-01

Toxic epidermal necrolysis (TEN) is a serious, life-threatening skin reaction characterized by severe exfoliation and destruction of the epidermis of the skin. In most TEN cases, drugs are believed to be the causative agent; antipsychotics, antiepileptics, and other medications such as sulfonamides are among the most common causes of drug-induced TEN. Phenytoin, a commonly prescribed medication for seizure, was found to cause TEN. Evidence-based treatment guidelines are lacking, so the best strategy is to identify and avoid potential risk factors and to provide intensive supportive care. The aim of this literature review is to focus on phenytoin-induced TEN, to explore the risk factors, and to highlight the possible treatment options once phenytoin-induced TEN is confirmed. PMID:27651708

Causes and effects of a highly successful marine invasion: Case-study of the introduced Pacific oyster Crassostrea gigas in continental NW European estuaries

NASA Astrophysics Data System (ADS)

Troost, Karin

2010-10-01

Since the 1960's, the Pacific oyster Crassostrea gigas has been introduced for mariculture at several locations within NW Europe. The oyster established itself everywhere and expanded rapidly throughout the receiving ecosystems, forming extensive and dense reef structures. It became clear that the Pacific oyster induced major changes in NW European estuaries. This paper reviews the causes of the Pacific oyster's remarkably successful establishment and spread in The Netherlands and neighbouring countries, and includes a comprehensive review of consequences for the receiving communities. Ecosystem engineering by C. gigas and a relative lack of natural enemies in receiving ecosystems are identified as the most important characteristics facilitating the invader's successful establishment and expansion. The Pacific oyster's large filtration capacity and eco-engineering characteristics induced many changes in receiving ecosystems. Different estuaries are affected differently; in the Dutch Oosterschelde estuary expanding stocks saturate the carrying capacity whereas in the Wadden Sea no such problems exist. In general, the Pacific oyster seems to fit well within continental NW European estuarine ecosystems and there is no evidence that the invader outcompetes native bivalves. C. gigas induces changes in plankton composition, habitat heterogeneity and biodiversity, carrying capacity, food webs and parasite life cycles. The case of the Pacific oyster in NW European estuaries is only one example in an increasing series of biological invasions mediated by human activities. This case-study will contribute to further elucidating general mechanisms in marine invasions; invasions that sometimes appear a threat, but can also contribute to ecological complexity.

Boxer crabs induce asexual reproduction of their associated sea anemones by splitting and intraspecific theft

PubMed Central

Karplus, Ilan; Achituv, Yair

2017-01-01

Crabs of the genus Lybia have the remarkable habit of holding a sea anemone in each of their claws. This partnership appears to be obligate, at least on the part of the crab. The present study focuses on Lybia leptochelis from the Red Sea holding anemones of the genus Alicia (family Aliciidae). These anemones have not been found free living, only in association with L. leptochelis. In an attempt to understand how the crabs acquire them, we conducted a series of behavioral experiments and molecular analyses. Laboratory observations showed that the removal of one anemone from a crab induces a “splitting” behavior, whereby the crab tears the remaining anemone into two similar parts, resulting in a complete anemone in each claw after regeneration. Furthermore, when two crabs, one holding anemones and one lacking them, are confronted, the crabs fight, almost always leading to the “theft” of a complete anemone or anemone fragment by the crab without them. Following this, crabs “split” their lone anemone into two. Individuals of Alicia sp. removed from freshly collected L. leptochelis were used for DNA analysis. By employing AFLP (Fluorescence Amplified Fragments Length Polymorphism) it was shown that each pair of anemones from a given crab is genetically identical. Furthermore, there is genetic identity between most pairs of anemone held by different crabs, with the others showing slight genetic differences. This is a unique case in which one animal induces asexual reproduction of another, consequently also affecting its genetic diversity. PMID:28168117

Pathophysiology of infantile pulmonary arterial hypertension induced by monocrotaline.

PubMed

Dias-Neto, Marina; Luísa-Neves, Ana; Pinho, Sónia; Gonçalves, Nádia; Mendes, Maria; Eloy, Catarina; Lopes, José M; Gonçalves, Daniel; Ferreira-Pinto, Manuel; Leite-Moreira, Adelino F; Henriques-Coelho, Tiago

2015-06-01

Pediatric pulmonary arterial hypertension (PAH) presents certain specific features. In this specific age group, experimental models to study the pathophysiology of PAH are lacking. To characterize hemodynamic, morphometric, and histological progression as well as the expression of neurohumoral factors and regulators of cardiac transcription in an infantile model of PAH induced by monocrotaline (MCT), eight-day-old Wistar rats were randomly injected with MCT (30 mg/kg, sc, n = 95) or equal volume of saline solution (n = 92). Animals were instrumented for biventricular hemodynamic recording 7, 14, and 21 days after MCT, whereas samples were collected at 1, 3, 7, 14, and 21 days after MCT. Different time point postinjections were defined for further analysis. Hearts and lungs were collected for morphometric characterization, assessment of right- and left-ventricle (RV and LV) cardiomyocyte diameter and collagen type-I and type-III ratio, RV collagen volume fraction, and pulmonary vessels wall thickness. mRNA quantification was undertaken for brain natriuretic peptide (BNP), endothelin-1 (ET-1), and for cardiac transcription regulators (HOP and Islet1). Animals treated with MCT at the 8th day of life presented RV hypertrophy since day 14 after MCT injection. There were no differences on the RV collagen volume fraction or collagen type-I and type-III ratio. Pulmonary vascular remodelling and PAH were present on day 21, which were accompanied by an increased expression of BNP, ET-1, HOP, and Islet1. The infantile model of MCT-induced PAH can be useful for the study of its pathophysiology and to test new therapeutic targets in pediatric age group.

T-cell expression of AhR inhibits the maintenance of pTreg cells in the gastrointestinal tract in acute GVHD.

PubMed

Dant, Trisha A; Lin, Kaifeng L; Bruce, Danny W; Montgomery, Stephanie A; Kolupaev, Oleg V; Bommiasamy, Hemamalini; Bixby, Lisa M; Woosley, John T; McKinnon, Karen P; Gonzalez, Frank J; Blazar, Bruce R; Vincent, Benjamin G; Coghill, James M; Serody, Jonathan S

2017-07-20

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that affects the function and development of immune cells. Here, we show that recipient mice receiving AhR -/- T cells have improved survival and decreased acute graft-versus-host disease (aGVHD) in 2 different murine allogeneic bone marrow transplant (BMT) models. We also show that CD4 + T cells lacking AhR demonstrate reduced accumulation in secondary lymphoid tissue because of low levels of proliferation 4 days after BMT. Additionally, we found a significant increase in the quantity of peripherally induced regulatory donor T (pT reg ) cells in the colon of recipients transplanted with AhR -/- T cells 14 days after transplant. Blockade of AhR using a clinically available AhR antagonist greatly enhanced the in vitro generation of inducible T reg (iT reg ) cells from naïve CD4 + human T cells. We have identified AhR as a novel target on donor T cells that is critical to the pathogenesis of aGVHD.

Changes in cell morphology due to plasma membrane wounding by acoustic cavitation

PubMed Central

Schlicher, Robyn K.; Hutcheson, Joshua D.; Radhakrishna, Harish; Apkarian, Robert P.; Prausnitz, Mark R.

2010-01-01

Acoustic cavitation-mediated wounding (i.e., sonoporation) has great potential to improve medical and laboratory applications requiring intracellular uptake of exogenous molecules; however, the field lacks detailed understanding of cavitation-induced morphological changes in cells and their relative importance. Here, we present an in-depth study of the effects of acoustic cavitation on cells using electron and confocal microscopy coupled with quantitative flow cytometry. High resolution images of treated cells show that morphologically different types of blebs can occur after wounding conditions caused by ultrasound exposure as well as by mechanical shear and strong laser ablation. In addition, these treatments caused wound-induced non-lytic necrotic death resulting in cell bodies we call wound-derived perikarya (WD-P). However, only cells exposed to acoustic cavitation experienced ejection of intact nuclei and nearly instant lytic necrosis. Quantitative analysis by flow cytometry indicates that wound-derived perikarya are the dominant morphology of nonviable cells, except at the strongest wounding conditions, where nuclear ejection accounts for a significant portion of cell death after ultrasound exposure. PMID:20350691

Combined experience of six independent laboratories attempting to create an Ewing sarcoma mouse model

PubMed Central

Han, Jenny; Han, Zhi-Yan; Sax, Barbara; Kream, Barbara E.; Hong, Sung-Hyeok; Çelik, Haydar; Tirode, Franck; Tuckermann, Jan; Toretsky, Jeffrey A.; Kenner, Lukas; Kovar, Heinrich; Lee, Sean; Sweet-Cordero, E. Alejandro; Nakamura, Takuro; Moriggl, Richard; Delattre, Olivier; Üren, Aykut

2017-01-01

Ewing sarcoma (ES) involves a tumor-specific chromosomal translocation that produces the EWS-FLI1 protein, which is required for the growth of ES cells both in vitro and in vivo. However, an EWS-FLI1-driven transgenic mouse model is not currently available. Here, we present data from six independent laboratories seeking an alternative approach to express EWS-FLI1 in different murine tissues. We used the Runx2, Col1a2.3, Col1a3.6, Prx1, CAG, Nse, NEFL, Dermo1, P0, Sox9 and Osterix promoters to target EWS-FLI1 or Cre expression. Additional approaches included the induction of an endogenous chromosomal translocation, in utero knock-in, and the injection of Cre-expressing adenovirus to induce EWS-FLI1 expression locally in multiple lineages. Most models resulted in embryonic lethality or developmental defects. EWS-FLI1-induced apoptosis, promoter leakiness, the lack of potential cofactors, and the difficulty of expressing EWS-FLI1 in specific sites were considered the primary reasons for the failed attempts to create a transgenic mouse model of ES. PMID:27191748

[Effects of exercise on joints.

PubMed

Moriyama, Hideki

Joints are composed of several different tissues(cartilage, capsule, meniscus, and ligament), and articular cartilage plays an important role in maintaining mechanical competence during exercise. Weight-bearing exercise has several benefit, including improved blood and synovial fluid circulation in a given joint. Consistent moderate activities facilitate cycles of anabolism and catabolism. Mechanical stresses are crucial for the maintenance of the morphologic and functional integrity of articular cartilage. Healthy cartilage is exposed by hydrostatic pressure and tensile strain, when cartilage degeneration develops, abnormal cartilage is exposed by shear stress. Moderate(physiological)exercise is characterized by a range of equilibrium between matrix anabolic and catabolic processes, or anabolism beyond catabolism. Joints are susceptible to insufficient or excessive activities, leading to joint degeneration. Lack of exercise is known to induce joint contracture seen clinically as a consequence of disuse changes, and excess mechanical stresses induce joint destruction such as osteoarthritis. Joint diseases resulting from insufficient or excessive activities are new and major challenging issues with our aging population. Thus, it is highly desirable to have an effective and efficient treatment to improve and protect against these joint diseases, and thereby to solve these clearly unanswered issues.

Quantitative observations of hydrogen-induced, slow crack growth in a low alloy steel

NASA Technical Reports Server (NTRS)

Nelson, H. G.; Williams, D. P.

1973-01-01

Hydrogen-induced slow crack growth, da/dt, was studied in AISI-SAE 4130 low alloy steel in gaseous hydrogen and distilled water environments as a function of applied stress intensity, K, at various temperatures, hydrogen pressures, and alloy strength levels. At low values of K, da/dt was found to exhibit a strong exponential K dependence (Stage 1 growth) in both hydrogen and water. At intermediate values of K, da/dt exhibited a small but finite K dependence (Stage 2), with the Stage 2 slope being greater in hydrogen than in water. In hydrogen, at a constant K, (da/dt) sub 2 varied inversely with alloy strength level and varied essentially in the same complex manner with temperature and hydrogen pressure as noted previously. The results of this study provide support for most of the qualitative predictions of the lattice decohesion theory as recently modified by Oriani. The lack of quantitative agreement between data and theory and the inability of theory to explain the observed pressure dependence of slow crack growth are mentioned and possible rationalizations to account for these differences are presented.

Scalable topographies to support proliferation and Oct4 expression by human induced pluripotent stem cells

PubMed Central

Reimer, Andreas; Vasilevich, Aliaksei; Hulshof, Frits; Viswanathan, Priyalakshmi; van Blitterswijk, Clemens A.; de Boer, Jan; Watt, Fiona M.

2016-01-01

It is well established that topographical features modulate cell behaviour, including cell morphology, proliferation and differentiation. To define the effects of topography on human induced pluripotent stem cells (iPSC), we plated cells on a topographical library containing over 1000 different features in medium lacking animal products (xeno-free). Using high content imaging, we determined the effect of each topography on cell proliferation and expression of the pluripotency marker Oct4 24 h after seeding. Features that maintained Oct4 expression also supported proliferation and cell-cell adhesion at 24 h, and by 4 days colonies of Oct4-positive, Sox2-positive cells had formed. Computational analysis revealed that small feature size was the most important determinant of pluripotency, followed by high wave number and high feature density. Using this information we correctly predicted whether any given topography within our library would support the pluripotent state at 24 h. This approach not only facilitates the design of substrates for optimal human iPSC expansion, but also, potentially, identification of topographies with other desirable characteristics, such as promoting differentiation. PMID:26757610

Scalable topographies to support proliferation and Oct4 expression by human induced pluripotent stem cells.

PubMed

Reimer, Andreas; Vasilevich, Aliaksei; Hulshof, Frits; Viswanathan, Priyalakshmi; van Blitterswijk, Clemens A; de Boer, Jan; Watt, Fiona M

2016-01-13

It is well established that topographical features modulate cell behaviour, including cell morphology, proliferation and differentiation. To define the effects of topography on human induced pluripotent stem cells (iPSC), we plated cells on a topographical library containing over 1000 different features in medium lacking animal products (xeno-free). Using high content imaging, we determined the effect of each topography on cell proliferation and expression of the pluripotency marker Oct4 24 h after seeding. Features that maintained Oct4 expression also supported proliferation and cell-cell adhesion at 24 h, and by 4 days colonies of Oct4-positive, Sox2-positive cells had formed. Computational analysis revealed that small feature size was the most important determinant of pluripotency, followed by high wave number and high feature density. Using this information we correctly predicted whether any given topography within our library would support the pluripotent state at 24 h. This approach not only facilitates the design of substrates for optimal human iPSC expansion, but also, potentially, identification of topographies with other desirable characteristics, such as promoting differentiation.

Combined experience of six independent laboratories attempting to create an Ewing sarcoma mouse model.

PubMed

Minas, Tsion Zewdu; Surdez, Didier; Javaheri, Tahereh; Tanaka, Miwa; Howarth, Michelle; Kang, Hong-Jun; Han, Jenny; Han, Zhi-Yan; Sax, Barbara; Kream, Barbara E; Hong, Sung-Hyeok; Çelik, Haydar; Tirode, Franck; Tuckermann, Jan; Toretsky, Jeffrey A; Kenner, Lukas; Kovar, Heinrich; Lee, Sean; Sweet-Cordero, E Alejandro; Nakamura, Takuro; Moriggl, Richard; Delattre, Olivier; Üren, Aykut

2017-05-23

Ewing sarcoma (ES) involves a tumor-specific chromosomal translocation that produces the EWS-FLI1 protein, which is required for the growth of ES cells both in vitro and in vivo. However, an EWS-FLI1-driven transgenic mouse model is not currently available. Here, we present data from six independent laboratories seeking an alternative approach to express EWS-FLI1 in different murine tissues. We used the Runx2, Col1a2.3, Col1a3.6, Prx1, CAG, Nse, NEFL, Dermo1, P0, Sox9 and Osterix promoters to target EWS-FLI1 or Cre expression. Additional approaches included the induction of an endogenous chromosomal translocation, in utero knock-in, and the injection of Cre-expressing adenovirus to induce EWS-FLI1 expression locally in multiple lineages. Most models resulted in embryonic lethality or developmental defects. EWS-FLI1-induced apoptosis, promoter leakiness, the lack of potential cofactors, and the difficulty of expressing EWS-FLI1 in specific sites were considered the primary reasons for the failed attempts to create a transgenic mouse model of ES.

A critical role for plasma kallikrein in the pathogenesis of autoantibody-induced arthritis.

PubMed

Yang, Aizhen; Zhou, Junsong; Wang, Bo; Dai, Jihong; Colman, Robert W; Song, Wenchao; Wu, Yi

2017-12-01

The plasma kallikrein-kinin system (KKS) consists of serine proteases, prekallikrein (pKal) and factor XII (FXII), and a cofactor, high-MW kininogen (HK). Upon activation, activated pKal and FXII cleave HK to release bradykinin. Activation of this system has been noted in patients with rheumatoid arthritis, and its pathogenic role has been characterized in animal arthritic models. In this study, we generated 2 knockout mouse strains that lacked pKal and HK and determined the role of KKS in autoantibody-induced arthritis. In a K/BxN serum transfer-induced arthritis (STIA) model, mice that lacked HK, pKal, or bradykinin receptors displayed protective phenotypes in joint swelling, histologic changes in inflammation, and cytokine production; however, FXII-deficient mice developed normal arthritis. Inhibition of Kal ameliorated arthritis severity and incidence at early stage STIA and reduced the levels of major cytokines in joints. In addition to releasing bradykinin from HK, Kal directly activated monocytes to produce proinflammatory cytokines, up-regulated their C5aR and FcRIII expression, and released C5a. Immune complex increased pKal activity, which led to HK cleavage. The absence of HK is associated with a decrease in joint vasopermeability. Thus, we identify a critical role for Kal in autoantibody-induced arthritis with pleiotropic effects, which suggests that it is a new target for the inhibition of arthritis.-Yang, A., Zhou, J., Wang, B., Dai, J., Colman, R. W., Song, W., Wu, Y. A critical role for plasma kallikrein in the pathogenesis of autoantibody-induced arthritis. © FASEB.

Fluvial sediment transport and deposition following the 1991 eruption of Mount Pinatubo

USGS Publications Warehouse

Hayes, S.K.; Montgomery, D.R.; Newhall, C.G.

2002-01-01

The 1991 eruption of Mount Pinatubo generated extreme sediment yields from watersheds heavily impacted by pyroclastic flows. Bedload sampling in the Pasig-Potrero River, one of the most heavily impacted rivers, revealed negligible critical shear stress and very high transport rates that reflected an essentially unlimited sediment supply and the enhanced mobility of particles moving over a smooth, fine-grained bed. Dimensionless bedload transport rates in the Pasig-Potrero River differed substantially from those previously reported for rivers in temperate regions for the same dimensionless shear stress, but were similar to rates identified in rivers on other volcanoes and ephemeral streams in arid environments. The similarity between volcanically disturbed and arid rivers appears to arise from the lack of an armored bed surface due to very high relative sediment supply; in arid rivers, this is attributed to a flashy hydrograph, whereas volcanically disturbed rivers lack armoring due to sustained high rates of sediment delivery. This work suggests that the increases in sediment supply accompanying massive disturbance induce morphologic and hydrologic changes that temporarily enhance transport efficiency until the watershed recovers and sediment supply is reduced. ?? 2002 Elsevier Science B.V. All rights reserved.

Conditional expression of the dominant-negative TGF-β receptor type II elicits lingual epithelial hyperplasia in transgenic mice.

PubMed

Li, Feng; Zhou, Mingliang

2013-05-01

The transforming growth factor-β (TGF-β) signaling pathway is generally believed to be a potent inhibitor of proliferation. However, many epithelia lacking the essential Tgfbr2 gene still maintain normal tissue homeostasis. Here, transgenic mice expressing rtTA from the human keratin 14 (K14) promoter were used to generate an inducible dominant-negative TGF-β receptor type II (Tgfbr2) mutant model, which allowed us to distinguish between the primary and secondary effects of TGF-β signaling disruption by Doxycycline treatment in K14+ epithelial stem cells. We showed that in mice lacking TGF-β signaling in K14+ cells, invasive carcinomas developed on the ventral surface of the tip of the tongue, while filiform papillae on the dorsal surface showed different pathological changes from the tip to the posterior of the tongue. In addition, acetylation levels of histone H4 and histone H3 rapidly increased, while pMAPK activity was enhanced and Jagged2 inactivated in lingual epithelia after disruption of TGF-β signaling. Our results contribute to the understanding of TGF-β signaling in regulating homeostasis and carcinogenesis in lingual epithelia. Copyright © 2013 Wiley Periodicals, Inc.

Interaction of THP-1 Monocytes with Conidia and Hyphae of Different Curvularia Strains

PubMed Central

Tóth, Eszter Judit; Boros, Éva; Hoffmann, Alexandra; Szebenyi, Csilla; Homa, Mónika; Nagy, Gábor; Vágvölgyi, Csaba; Nagy, István; Papp, Tamás

2017-01-01

Interaction of the human monocytic cell line, THP-1 with clinical isolates of three Curvularia species were examined. Members of this filamentous fungal genus can cause deep mycoses emerging in both immunocompromised and immunocompetent patients. It was found that monocytes reacted only to the hyphal form of Curvularia lunata. Cells attached to the germ tubes and hyphae and production of elevated levels of interleukin (IL)-8 and IL-10 and a low level of TNF-α were measured. At the same time, monocytes failed to produce IL-6. This monocytic response, especially with the induction of the anti-inflammatory IL-10, correlates well to the observation that C. lunata frequently cause chronic infections even in immunocompetent persons. Despite the attachment to the hyphae, monocytes could not reduce the viability of the fungus and the significant decrease in the relative transcript level of HLA-DRA assumes the lack of antigen presentation of the fungus by this cell type. C. spicifera and C. hawaiiensis failed to induce the gathering of the cells or the production of any analyzed cytokines. Monocytes did not recognize conidia of Curvularia species, even when melanin was lacking in their cell wall. PMID:29093719

Combining morphometrics with molecular taxonomy: how different are similar foliose keratose sponges from the Australian tropics?

PubMed

Abdul Wahab, M A; Fromont, J; Whalan, S; Webster, N; Andreakis, N

2014-04-01

Sponge taxonomy can be challenging as many groups exhibit extreme morphological plasticity induced by local environmental conditions. Foliose keratose sponges of the sub-family Phyllospongiinae (Dictyoceratida, Thorectidae: Strepsichordaia, Phyllospongia and Carteriospongia) are commonly found in intertidal and subtidal habitats of the Indo-Pacific. Lacking spicules, these sponges can be difficult to differentiate due to the lack of reliable morphological characters for species delineation. We use molecular phylogenies inferred from the nuclear Internal Transcribed Spacer 2 region (ITS2) and morphometrics (19 characters; 52 character states) to identify evolutionarily significant units (ESUs; sensu Moritz) within foliose Phyllosponginiids collected from seven geographic locations across tropical eastern and Western Australia. The ITS2 topology was congruent with the tree derived from Bayesian inference of discrete morphological characters supporting expected taxonomic relationships at the genus level and the identification of five ESUs. However, phylogenies inferred from the ITS2 marker revealed multiple sequence clusters, some of which were characterised by distinct morphological features and specific geographic ranges. Our results are discussed in light of taxonomic incongruences within this study, hidden sponge diversity and the role of vicariant events in influencing present day distribution patterns. Copyright © 2014 Elsevier Inc. All rights reserved.

Interaction of THP-1 Monocytes with Conidia and Hyphae of Different Curvularia Strains.

PubMed

Tóth, Eszter Judit; Boros, Éva; Hoffmann, Alexandra; Szebenyi, Csilla; Homa, Mónika; Nagy, Gábor; Vágvölgyi, Csaba; Nagy, István; Papp, Tamás

2017-01-01

Interaction of the human monocytic cell line, THP-1 with clinical isolates of three Curvularia species were examined. Members of this filamentous fungal genus can cause deep mycoses emerging in both immunocompromised and immunocompetent patients. It was found that monocytes reacted only to the hyphal form of Curvularia lunata . Cells attached to the germ tubes and hyphae and production of elevated levels of interleukin (IL)-8 and IL-10 and a low level of TNF-α were measured. At the same time, monocytes failed to produce IL-6. This monocytic response, especially with the induction of the anti-inflammatory IL-10, correlates well to the observation that C. lunata frequently cause chronic infections even in immunocompetent persons. Despite the attachment to the hyphae, monocytes could not reduce the viability of the fungus and the significant decrease in the relative transcript level of HLA-DRA assumes the lack of antigen presentation of the fungus by this cell type. C. spicifera and C. hawaiiensis failed to induce the gathering of the cells or the production of any analyzed cytokines. Monocytes did not recognize conidia of Curvularia species, even when melanin was lacking in their cell wall.

Lack of insula reactivity to aversive stimuli in schizophrenia.

PubMed

Linnman, Clas; Coombs, Garth; Goff, Donald C; Holt, Daphne J

2013-01-01

Patients with schizophrenia may have altered pain perception, as suggested by clinical reports of pain insensitivity, and recent neuroimaging findings. Here, we examined neural responses to an aversive electrical stimulus and the immediate anticipation of such a stimulus using fMRI and a classical conditioning paradigm, which involved pairing an electrical shock with a neutral photograph. Fifteen men with schizophrenia and 13 healthy men, matched for demographic characteristics, electrical stimulation level and scan movement, were studied. The shock induced robust responses in midbrain, thalamus, cingulate gyrus, insula and somatosensory cortex in both groups. However, compared to controls, the schizophrenic patients displayed significantly lower activation of the middle insula (p(FWE)=0.002, T=5.72, cluster size=24 voxels). Moreover, the lack of insula reactivity in the schizophrenia group was predicted by the magnitude of positive symptoms (r=-0.46, p=0.04). In contrast, there were no significant differences between the two groups in the magnitude of neural responses during anticipation of the shock. These findings provide support for the existence of a basic deficit in interoceptive perception in schizophrenia, which could play a role in the generation and/or maintenance of psychotic states. Copyright © 2012 Elsevier B.V. All rights reserved.

The Major DNA Repair Pathway after Both Proton and Carbon-Ion Radiation is NHEJ, but the HR Pathway is More Relevant in Carbon Ions

PubMed Central

Gerelchuluun, Ariungerel; Manabe, Eri; Ishikawa, Takaaki; Sun, Lue; Itoh, Kazuya; Sakae, Takeji; Suzuki, Kenshi; Hirayama, Ryoichi; Asaithamby, Aroumougame; Chen, David J.; Tsuboi, Koji

2017-01-01

The purpose of this study was to identify the roles of non-homologous end-joining (NHEJ) or homologous recombination (HR) pathways in repairing DNA double-strand breaks (DSBs) induced by exposure to high-energy protons and carbon ions (C ions) versus gamma rays in Chinese hamster cells. Two Chinese hamster cell lines, ovary AA8 and lung fibroblast V79, as well as various mutant sublines lacking DNA-PKcs (V3), X-ray repair cross-complementing protein-4 [XRCC4 (XR1), XRCC3 (irs1SF) and XRCC2 (irs1)] were exposed to gamma rays (137Cs), protons (200 MeV; 2.2 keV/μm) and C ions (290 MeV; 50 keV/μm). V3 and XR1 cells lack the NHEJ pathway, whereas irs1 and irs1SF cells lack the HR pathway. After each exposure, survival was measured using a clonogenic survival assay, in situ DSB induction was evaluated by immunocytochemical analysis of histone H2AX phosphorylation at serine 139 (γ-H2AX foci) and chromosome aberrations were examined using solid staining. The findings from this study showed that clonogenic survival clearly depended on the NHEJ and HR pathway statuses, and that the DNA-PKcs−/− cells (V3) were the most sensitive to all radiation types. While protons and γ rays yielded almost the same biological effects, C-ion exposure greatly enhanced the sensitivity of wild-type and HR-deficient cells. However, no significant enhancement of sensitivity in cell killing was seen after C-ion irradiation of NHEJ deficient cells. Decreases in the number of γ-H2AX foci after irradiation occurred more slowly in the NHEJ deficient cells. In particular, V3 cells had the highest number of residual γ-H2AX foci at 24 h after C-ion irradiation. Chromosomal aberrations were significantly higher in both the NHEJ- and HR-deficient cell lines than in wild-type cell lines in response to all radiation types. Protons and gamma rays induced the same aberration levels in each cell line, whereas C ions introduced higher but not significantly different aberration levels. Our results suggest that the NHEJ pathway plays an important role in repairing DSBs induced by both clinical proton and C-ion beams. Furthermore, in C ions the HR pathway appears to be involved in the repair of DSBs to a greater extent compared to gamma rays and protons. PMID:25738894

Alterations in anxiety and social behaviour in Npas4 deficient mice following photochemically-induced focal cortical stroke.

PubMed

Klarić, T S; Jaehne, E J; Koblar, S A; Baune, B T; Lewis, M D

2017-01-01

In addition to causing widespread cell death and loss of brain function, cerebral ischaemia also induces extensive neuroplasticity. In humans, stroke is often accompanied by severe cognitive and psychiatric changes that are thought to arise as a consequence of this infarct-induced remodelling. A candidate for producing these post-stroke neuropsychiatric changes is Npas4, an activity-dependent transcription factor involved in synaptic plasticity whose expression is aberrantly up-regulated following ischaemic injury. In this study we investigated the role of Npas4 in modulating these stroke-induced neuropsychiatric responses by comparing the performance of wildtype and Npas4 -/- mice in various cognitive and behavioural tasks in a photochemical model of focal cortical stroke. We show that this stroke model results in impaired spatial recognition memory and a reduction in despair-like behaviour that affect both genotypes to a similar degree. Moreover, mice lacking Npas4 also show differences in some aspects of post-stroke sociability and anxiety. Specifically, we show that while stroke had no effect on anxiety levels in wildtype mice, Npas4 -/- mice became significantly more anxious following stroke. In addition, Npas4 -/- mice retained a greater level of sociability in the acute post-stroke period in comparison to their wildtype littermates. Thus, our findings suggest that Npas4 may be involved in post-stroke psychiatric changes related to anxiety and sociability. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.

The Physiological Role of Abscisic Acid in Eliciting Turion Morphogenesis.

PubMed Central

Smart, C. C.; Fleming, A. J.; Chaloupkova, K.; Hanke, D. E.

1995-01-01

The exogenous application of hormones has led to their implication in a number of processes within the plant. However, proof of their function in vivo depends on quantitative data demonstrating that the exogenous concentration used to elicit a response leads to tissue hormone levels within the physiological range. Such proof is often lacking in many investigations. We are using abscisic acid (ABA)-induced turion formation in Spirodela polyrrhiza L. to investigate the mechanism by which a hormone can trigger a morphogenic switch. In this paper, we demonstrate that the exogenous concentration of ABA used to induce turions leads to tissue concentrations of ABA within the physiological range, as quantified by both enzyme-linked immunosorbent assay and high-performance liquid chromatography/gas chromatography-electron capture detection analysis. These results are consistent with ABA having a physiological role in turion formation, and they provide an estimate of the changes in endogenous ABA concentration required if environmental effectors of turion formation (e.g. nitrate deficiency, cold) act via an increased level of ABA. In addition, we show that the (+)- and (-)-enantiomers of ABA are equally effective in inducing turions. Moreover, comparison of the ABA; levels attained after treatment with (+)-, (-)-, and ([plus or minus])-ABA and their effect on turion induction and comparison of the effectiveness of ABA on turion induction under different pH regimes suggest that ABA most likely interacts with a plasmalemma-located receptor system to induce turion formation. PMID:12228499

Four Foodborne Disease Outbreaks Caused by a New Type of Enterotoxin-Producing Clostridium perfringens

PubMed Central

Hatakeyama, Kaoru; Obata, Hiromi; Yokoyama, Keiko; Konishi, Noriko; Itoh, Takeshi; Kai, Akemi

2015-01-01

The epidemiological and bacteriological investigations on four foodborne outbreaks caused by a new type of enterotoxin-producing Clostridium perfringens are described. C. perfringens isolated from patients of these outbreaks did not produce any known enterotoxin and did not carry the C. perfringens enterotoxin gene. However, the culture filtrates of these isolates induced the accumulation of fluid in rabbit ileal loop tests. The molecular weight of the new enterotoxin may be between 50,000 and 100,000, although the known C. perfringens enterotoxin is ca. 35,000. This new enterotoxin was heat labile, and its biological activities were inactivated by heating for 5 min at 60°C. The new enterotoxin was sensitive to pH values higher than 11.0 and protease treatment but was resistant to trypsin treatment. These results suggest that the new enterotoxin may be a protein. Although C. perfringens enterotoxin induced morphological changes in Vero cells, the changes induced by the new enterotoxin differed from those by the known C. perfringens enterotoxin. The new enterotoxin also induced morphological changes in L929 cells, whereas the known C. perfringens enterotoxin did not, because L929 cells lacked an appropriate enterotoxin receptor. Although C. perfringens enterotoxin is recognized as the only diarrheagenic toxin responsible for C. perfringens foodborne outbreaks, the results of the present study indicate that C. perfringens isolated from these four outbreaks produced a new type of enterotoxin. PMID:25568432

An essential role of mast cells in the development of airway hyperresponsiveness in a murine asthma model.

PubMed

Kobayashi, T; Miura, T; Haba, T; Sato, M; Serizawa, I; Nagai, H; Ishizaka, K

2000-04-01

Immunization of BALB/c mice with alum-adsorbed OVA, followed by three bronchoprovocations with aerosolized OVA, resulted in the development of airway hyperresponsiveness (AHR) and allergic inflammation in the lung accompanied by severe infiltration of eosinophils into airways. In this murine asthma model, administration of monoclonal anti-IL-5 Ab before each Ag challenge markedly inhibited airway eosinophilia, but the treatment did not affect the development of AHR. Immunization and aerosol challenges with OVA following the same protocol failed to induce AHR in the mast cell-deficient W/Wv mice, but induced AHR in their congenic littermates, i.e., WBB6F1 (+/+) mice. No significant difference was found between the W/Wv mice and +/+ mice with respect to the IgE and IgG1 anti-OVA Ab responses and to the airway eosinophilia after Ag provocations. It was also found that reconstitution of W/Wv mice with bone marrow-derived mast cells cultured from normal littermates restored the capacity of developing Ag-induced AHR, indicating that lack of mast cells was responsible for the failure of W/Wv mice to develop Ag-induced AHR under the experimental conditions. However, the OVA-immunized W/Wv mice developed AHR by increasing the frequency and Ag dose of bronchoprovocations. The results suggested that AHR could be developed by two distinct cellular mechanisms. One would go through mast cell activation and the other is IgE/mast cell independent but an eosinophil/IL-5-dependent mechanism.

Low mass planet migration in magnetically torqued dead zones - I. Static migration torque

NASA Astrophysics Data System (ADS)

McNally, Colin P.; Nelson, Richard P.; Paardekooper, Sijme-Jan; Gressel, Oliver; Lyra, Wladimir

2017-12-01

Motivated by models suggesting that the inner planet forming regions of protoplanetary discs are predominantly lacking in viscosity-inducing turbulence, and are possibly threaded by Hall-effect generated large-scale horizontal magnetic fields, we examine the dynamics of the corotation region of a low-mass planet in such an environment. The corotation torque in an inviscid, isothermal, dead zone ought to saturate, with the libration region becoming both symmetrical and of a uniform vortensity, leading to fast inward migration driven by the Lindblad torques alone. However, in such a low viscosity situation, the material on librating streamlines essentially preserves its vortensity. If there is relative radial motion between the disc gas and the planet, the librating streamlines will no longer be symmetrical. Hence, if the gas is torqued by a large-scale magnetic field so that it undergoes a net inflow or outflow past the planet, driving evolution of the vortensity and inducing asymmetry of the corotation region, the corotation torque can grow, leading to a positive torque. In this paper, we treat this effect by applying a symmetry argument to the previously studied case of a migrating planet in an inviscid disc. Our results show that the corotation torque due to a laminar Hall-induced magnetic field in a dead zone behaves quite differently from that studied previously for a viscous disc. Furthermore, the magnetic field induced corotation torque and the dynamical corotation torque in a low viscosity disc can be regarded as one unified effect.

Seizure susceptibility of neuropeptide-Y null mutant mice in amygdala kindling and chemical-induced seizure models.

PubMed

Shannon, Harlan E; Yang, Lijuan

2004-01-01

Neuropeptide Y (NPY) administered exogenously is anticonvulsant, and, NPY null mutant mice are more susceptible to kainate-induced seizures. In order to better understand the potential role of NPY in epileptogenesis, the present studies investigated the development of amygdala kindling, post-kindling seizure thresholds, and anticonvulsant effects of carbamazepine and levetiracetam in 129S6/SvEv NPY(+/+) and NPY(-/-) mice. In addition, susceptibility to pilocarpine- and kainate-induced seizures was compared in NPY(+/+) and (-/-) mice. The rate of amygdala kindling development did not differ in the NPY(-/-) and NPY(+/+) mice either when kindling stimuli were presented once daily for at least 20 days, or, 12 times daily for 2 days. However, during kindling development, the NPY(-/-) mice had higher seizure severity scores and longer afterdischarge durations than the NPY(+/+) mice. Post-kindling, the NPY(-/-) mice had markedly lower afterdischarge thresholds and longer afterdischarge durations than NPY (+/+) mice. Carbamazepine and levetiracetam increased the seizure thresholds of both NPY (-/-) and (+/+) mice. In addition, NPY (-/-) mice had lower thresholds for both kainate- and pilocarpine-induced seizures. The present results in amygdala kindling and chemical seizure models suggest that NPY may play a more prominent role in determining seizure thresholds and severity of seizures than in events leading to epileptogenesis. In addition, a lack of NPY does not appear to confer drug-resistance in that carbamazepine and levetiracetam were anticonvulsant in both wild type (WT) and NPY null mutant mice.

c-Jun and Hypoxia-Inducible Factor 1 Functionally Cooperate in Hypoxia-Induced Gene Transcription

PubMed Central

Alfranca, Arántzazu; Gutiérrez, M. Dolores; Vara, Alicia; Aragonés, Julián; Vidal, Felipe; Landázuri, Manuel O.

2002-01-01

Under low-oxygen conditions, cells develop an adaptive program that leads to the induction of several genes, which are transcriptionally regulated by hypoxia-inducible factor 1 (HIF-1). On the other hand, there are other factors which modulate the HIF-1-mediated induction of some genes by binding to cis-acting motifs present in their promoters. Here, we show that c-Jun functionally cooperates with HIF-1 transcriptional activity in different cell types. Interestingly, a dominant-negative mutant of c-Jun which lacks its transactivation domain partially inhibits HIF-1-mediated transcription. This cooperative effect is not due to an increase in the nuclear amount of the HIF-1α subunit, nor does it require direct binding of c-Jun to DNA. c-Jun and HIF-1α are able to associate in vivo but not in vitro, suggesting that this interaction involves the participation of additional proteins and/or a posttranslational modification of these factors. In this context, hypoxia induces phosphorylation of c-Jun at Ser63 in endothelial cells. This process is involved in its cooperative effect, since specific blockade of the JNK pathway and mutation of c-Jun at Ser63 and Ser73 impair its functional cooperation with HIF-1. The functional interplay between c-Jun and HIF-1 provides a novel insight into the regulation of some genes, such as the one for VEGF, which is a key regulator of tumor angiogenesis. PMID:11739718

Functional mechanotransduction is required for cisplatin-induced hair cell death in the zebrafish lateral line.

PubMed

Thomas, Andrew J; Hailey, Dale W; Stawicki, Tamara M; Wu, Patricia; Coffin, Allison B; Rubel, Edwin W; Raible, David W; Simon, Julian A; Ou, Henry C

2013-03-06

Cisplatin, one of the most commonly used anticancer drugs, is known to cause inner ear hair cell damage and hearing loss. Despite much investigation into mechanisms of cisplatin-induced hair cell death, little is known about the mechanism whereby cisplatin is selectively toxic to hair cells. Using hair cells of the zebrafish lateral line, we found that chemical inhibition of mechanotransduction with quinine and EGTA protected against cisplatin-induced hair cell death. Furthermore, we found that the zebrafish mutants mariner (myo7aa) and sputnik (cad23) that lack functional mechanotransduction were resistant to cisplatin-induced hair cell death. Using a fluorescent analog of cisplatin, we found that chemical or genetic inhibition of mechanotransduction prevented its uptake. These findings demonstrate that cisplatin-induced hair cell death is dependent on functional mechanotransduction in the zebrafish lateral line.

Generation of diverse neuronal subtypes in cloned populations of stem-like cells

PubMed Central

Varga, Balázs V; Hádinger, Nóra; Gócza, Elen; Dulberg, Vered; Demeter, Kornél; Madarász, Emília; Herberth, Balázs

2008-01-01

Background The central nervous tissue contains diverse subtypes of neurons with characteristic morphological and physiological features and different neurotransmitter phenotypes. The generation of neurons with defined neurotransmitter phenotypes seems to be governed by factors differently expressed along the anterior-posterior and dorsal-ventral body axes. The mechanisms of the cell-type determination, however, are poorly understood. Selected neuronal phenotypes had been generated from embryonic stem (ES) cells, but similar results were not obtained on more restricted neural stem cells, presumably due to the lack of homogeneous neural stem cell populations as a starting material. Results In the presented work, the establishment of different neurotransmitter phenotypes was investigated in the course of in vitro induced neural differentiation of a one-cell derived neuroectodermal cell line, in conjunction with the activation of various region-specific genes. For comparison, similar studies were carried out on the R1 embryonic stem (ES) and P19 multipotent embryonic carcinoma (EC) cells. In response to a short treatment with all-trans retinoic acid, all cell lines gave rise to neurons and astrocytes. Non-induced neural stem cells and self-renewing cells persisting in differentiated cultures, expressed "stemness genes" along with early embryonic anterior-dorsal positional genes, but did not express the investigated CNS region-specific genes. In differentiating stem-like cell populations, on the other hand, different region-specific genes, those expressed in non-overlapping regions along the body axes were activated. The potential for diverse regional specifications was induced in parallel with the initiation of neural tissue-type differentiation. In accordance with the wide regional specification potential, neurons with different neurotransmitter phenotypes developed. Mechanisms inherent to one-cell derived neural stem cell populations were sufficient to establish glutamatergic and GABAergic neuronal phenotypes but failed to manifest cathecolaminergic neurons. Conclusion The data indicate that genes involved in positional determination are activated along with pro-neuronal genes in conditions excluding any outside influences. Interactions among progenies of one cell derived neural stem cells are sufficient for the activation of diverse region specific genes and initiate different routes of neuronal specification. PMID:18808670

Mitochondrial bioenergetics and drug-induced toxicity in a panel of mouse embryonic fibroblasts with mitochondrial DNA single nucleotide polymorphisms

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

Pereira, Claudia V.; Oliveira, Paulo J.; Will, Yvonne

2012-10-15

Mitochondrial DNA (mtDNA) variations including single nucleotide polymorphisms (SNPs) have been proposed to be involved in idiosyncratic drug reactions. However, current in vitro and in vivo models lack the genetic diversity seen in the human population. Our hypothesis is that different cell strains with distinct mtDNA SNPs may have different mitochondrial bioenergetic profiles and may therefore vary in their response to drug-induced toxicity. Therefore, we used an in vitro system composed of four strains of mouse embryonic fibroblasts (MEFs) with mtDNA polymorphisms. We sequenced mtDNA from embryonic fibroblasts isolated from four mouse strains, C57BL/6J, MOLF/EiJ, CZECHII/EiJ and PERA/EiJ, with themore » latter two being sequenced for the first time. The bioenergetic profile of the four strains of MEFs was investigated at both passages 3 and 10. Our results showed that there were clear differences among the four strains of MEFs at both passages, with CZECHII/EiJ having a lower mitochondrial robustness when compared to C57BL/6J, followed by MOLF/EiJ and PERA/EiJ. Seven drugs known to impair mitochondrial function were tested for their effect on the ATP content of the four strains of MEFs in both glucose- and galactose-containing media. Our results showed that there were strain-dependent differences in the response to some of the drugs. We propose that this model is a useful starting point to study compounds that may cause mitochondrial off-target toxicity in early stages of drug development, thus decreasing the number of experimental animals used. -- Highlights: ► mtDNA SNPs may be linked to individual predisposition to drug-induced toxicity. ► CZECHII/EiJ and PERA/EiJ mtDNA was sequenced for the first time in this study. ► Strain-dependent mitochondrial capacity differences were measured. ► Strain-dependent differences in response to mitochondrial toxicants were observed.« less

The evolution of plasticity of dauer larva developmental arrest in the nematode Caenorhabditis elegans.

PubMed

Diaz, S Anaid; Viney, Mark

2015-03-01

Organisms can end up in unfavourable conditions and to survive this they have evolved various strategies. Some organisms, including nematodes, survive unfavourable conditions by undergoing developmental arrest. The model nematode Caenorhabditis elegans has a developmental choice between two larval forms, and it chooses to develop into the arrested dauer larva form in unfavourable conditions (specifically, a lack of food and high population density, indicated by the concentration of a pheromone). Wild C. elegans isolates vary extensively in their dauer larva arrest phenotypes, and this prompts the question of what selective pressures maintain such phenotypic diversity? To investigate this we grew C. elegans in four different environments, consisting of different combinations of cues that can induce dauer larva development: two combinations of food concentration (high and low) in the presence or absence of a dauer larva-inducing pheromone. Five generations of artificial selection of dauer larvae resulted in an overall increase in dauer larva formation in most selection regimes. The presence of pheromone in the environment selected for twice the number of dauer larvae, compared with environments not containing pheromone. Further, only a high food concentration environment containing pheromone increased the plasticity of dauer larva formation. These evolutionary responses also affected the timing of the worms' reproduction. Overall, these results give an insight into the environments that can select for different plasticities of C. elegans dauer larva arrest phenotypes, suggesting that different combinations of environmental cues can select for the diversity of phenotypically plastic responses seen in C. elegans.

Cecropins as a marker of Spodoptera frugiperda immunosuppression during entomopathogenic bacterial challenge.

PubMed

Duvic, B; Jouan, V; Essa, N; Girard, P-A; Pagès, S; Abi Khattar, Z; Volkoff, N-A; Givaudan, A; Destoumieux-Garzon, D; Escoubas, J-M

2012-06-01

An antimicrobial peptide (AMP) of the cecropin family was isolated by HPLC from plasma of the insect pest, Spodoptera frugiperda. Its molecular mass is 3910.9 Da as determined by mass spectrometry. Thanks to the EST database Spodobase, we were able to describe 13 cDNAs encoding six different cecropins which belong to the sub-families CecA, CecB, CecC and CecD. The purified peptide identified as CecB1 was chemically synthesized (syCecB1). It was shown to be active against Gram-positive and Gram-negative bacteria as well as fungi. Two closely related entomopathogenic bacteria, Xenorhabdus nematophila F1 and Xenorhabdus mauleonii VC01(T) showed different susceptibility to syCecB1. Indeed, X. nematophila was sensitive to syCecB1 whereas X. mauleonii had a minimal inhibitory concentration (MIC) eight times higher. Interestingly, injection of live X. nematophila into insects did not induce the expression of AMPs in hemolymph. This effect was not observed when this bacterium was heat-killed before injection. On the opposite, both live and heat-killed X. mauleonii induced the expression of AMPs in the hemolymph of S. frugiperda. The same phenomenon was observed for another immune-related protein lacking antimicrobial activity. Altogether, our data suggest that Xenorhabdus strains have developed different strategies to supplant the humoral defense mechanisms of S. frugiperda, either by increasing their resistance to AMPs or by preventing their expression during such host-pathogen interaction. Copyright © 2012 Elsevier Ltd. All rights reserved.

Biofilm Formation and Immunomodulatory Activity of Proteus mirabilis Clinically Isolated Strains.

PubMed

Fusco, Alessandra; Coretti, Lorena; Savio, Vittoria; Buommino, Elisabetta; Lembo, Francesca; Donnarumma, Giovanna

2017-02-15

Urinary tract infections (UTIs) and catheter-associated UTIs (CAUTIs) are the principal hospital-acquired infections. Proteus mirabilis is characterized by several virulence factors able to promote adhesion and biofilm formation and ameliorate the colonization of urinary tract and the formation of crystalline biofilms on the abiotic surface of the urinary catheters. Since, to date, the role of P. mirabilis in the etiopathogenesis of different types of urinary tract infections is not well established, in this study we sought to characterize two different clinically isolated strains of P. mirabilis (PM1 and PM2) with distinctive phenotypes and analyzed various virulence factors possibly implicated in the ability to induce UTIs and CAUTIs. In particular, we analyzed motility, biofilm formation both on abiotic and biotic surfaces of PM1 and PM2 and paralleled these parameters with the ability to induce an inflammatory response in an epithelial cell model. Results showed that PM1 displayed major motility and a capacity to form biofilm and was associated with an anti-inflammatory response of host cells. Conversely, PM2 exhibited lack motility and a had slower organization in biofilm but promoted an increase of proinflammatory cytokine expression in infected epithelial cells. Our study provides data useful to start uncovering the pathologic basis of P. mirabilis -associated urinary infections. The evidence of different virulence factors expressed by PM1 and PM2 highlights the possibility to use precise and personalized therapies targeting specific virulence pathways.

Nucleus accumbens neuronal maturation differences in young rats bred for low versus high voluntary running behaviour

PubMed Central

Roberts, Michael D; Toedebusch, Ryan G; Wells, Kevin D; Company, Joseph M; Brown, Jacob D; Cruthirds, Clayton L; Heese, Alexander J; Zhu, Conan; Rottinghaus, George E; Childs, Thomas E; Booth, Frank W

2014-01-01

We compared the nucleus accumbens (NAc) transcriptomes of generation 8 (G8), 34-day-old rats selectively bred for low (LVR) versus high voluntary running (HVR) behaviours in rats that never ran (LVRnon-run and HVRnon-run), as well as in rats after 6 days of voluntary wheel running (LVRrun and HVRrun). In addition, the NAc transcriptome of wild-type Wistar rats was compared. The purpose of this transcriptomics approach was to generate testable hypotheses as to possible NAc features that may be contributing to running motivation differences between lines. Ingenuity Pathway Analysis and Gene Ontology analyses suggested that ‘cell cycle’-related transcripts and the running-induced plasticity of dopamine-related transcripts were lower in LVR versus HVR rats. From these data, a hypothesis was generated that LVR rats might have less NAc neuron maturation than HVR rats. Follow-up immunohistochemistry in G9–10 LVRnon-run rats suggested that the LVR line inherently possessed fewer mature medium spiny (Darpp-32-positive) neurons (P < 0.001) and fewer immature (Dcx-positive) neurons (P < 0.001) than their G9–10 HVR counterparts. However, voluntary running wheel access in our G9–10 LVRs uniquely increased their Darpp-32-positive and Dcx-positive neuron densities. In summary, NAc cellularity differences and/or the lack of running-induced plasticity in dopamine signalling-related transcripts may contribute to low voluntary running motivation in LVR rats. PMID:24665095

Fatigue induced changes in conical implant-abutment connections.

PubMed

Blum, Kai; Wiest, Wolfram; Fella, Christian; Balles, Andreas; Dittmann, Jonas; Rack, Alexander; Maier, Dominik; Thomann, Ralf; Spies, Benedikt Christopher; Kohal, Ralf Joachim; Zabler, Simon; Nelson, Katja

2015-11-01

Based on the current lack of data and understanding of the wear behavior of dental two-piece implants, this study aims for evaluating the microgap formation and wear pattern of different implants in the course of cyclic loading. Several implant systems with different conical implant-abutment interfaces were purchased. The implants were first evaluated using synchrotron X-ray high-resolution radiography (SRX) and scanning electron microscopy (SEM). The implant-abutment assemblies were then subjected to cyclic loading at 98N and their microgap was evaluated after 100,000, 200,000 and 1 million cycles using SRX, synchrotron micro-tomography (μCT). Wear mechanisms of the implant-abutment connection (IAC) after 200,000 cycles and 1 million cycles were further characterized using SEM. All implants exhibit a microgap between the implant and abutment prior to loading. The gap size increased with cyclic loading with its changes being significantly higher within the first 200,000 cycles. Wear was seen in all implants regardless of their interface design. The wear pattern comprised adhesive wear and fretting. Wear behavior changed when a different mounting medium was used (brass vs. polymer). A micromotion of the abutment during cyclic loading can induce wear and wear particles in conical dental implant systems. This feature accompanied with the formation of a microgap at the IAC is highly relevant for the longevity of the implants. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Lack of Hypertonia in Thumb Muscles After Stroke

PubMed Central

Kamper, Derek G.; Rymer, William Z.

2010-01-01

Despite the importance of the thumb to hand function, little is known about the origins of thumb impairment poststroke. Accordingly, the primary purpose of this study was to assess whether thumb flexors have heightened stretch reflexes (SRs) following stroke-induced hand impairment. The secondary purpose was to compare SR characteristics of thumb flexors in relation to those of finger flexors since it is unclear whether SR properties of both muscle groups are similarly affected poststroke. Stretch reflexes in thumb and finger flexors were assessed at rest on the paretic side in each of 12 individuals with chronic, severe, stroke-induced hand impairment and in the dominant thumb in each of eight control subjects also at rest. Muscle activity and passive joint flexion torques were measured during imposed slow (SS) and fast stretches (FS) of the flexors that span the metacarpophalangeal joints. Putative spasticity was then quantified in terms of the peak difference between FS and SS joint torques and electromyographic changes. For both the hemiparetic and control groups, the mean normalized peak torque differences (PTDs) measured in thumb flexors were statistically indistinguishable (P = 0.57). In both groups, flexor muscles were primarily unresponsive to rapid stretching. For 10 of 12 hemiparetic subjects, PTDs in thumb flexors were less than those in finger flexors (P = 0.03). Paretic finger flexor muscle reflex activity was consistently elicited during rapid stretching. These results may reflect an important difference between thumb and finger flexors relating to properties of the involved muscle afferents and spinal motoneurons. PMID:20668270

Costunolide ameliorates lipoteichoic acid-induced acute lung injury via attenuating MAPK signaling pathway.

PubMed

Chen, Zhengxu; Zhang, Dan; Li, Man; Wang, Baolong

2018-06-12

Lipoteichoic acid (LTA)-induced acute lung injury (ALI) is an experimental model for mimicking Gram-positive bacteria-induced pneumonia that is a refractory disease with lack of effective medicines. Here, we reported that costunolide, a sesquiterpene lactone, ameliorated LTA-induced ALI. Costunolide treatment reduced LTA-induced neutrophil lung infiltration, cytokine and chemokine production (TNF-α, IL-6 and KC), and pulmonary edema. In response to LTA challenge, treatment with costunolide resulted less iNOS expression and produced less inflammatory cytokines in bone marrow derived macrophages (BMDMs). Pretreatment with costunolide also attenuated the LTA-induced the phosphorylation of p38 MAPK and ERK in BMDMs. Furthermore, costunolide treatment reduced the phosphorylation of TAK1 and inhibited the interaction of TAK1 with Tab1. In conclusion, we have demonstrated that costunolide protects against LTA-induced ALI via inhibiting TAK1-mediated MAPK signaling pathway, and our studies suggest that costunolide is a promising agent for treatment of Gram-positive bacteria-mediated pneumonia. Copyright © 2018 Elsevier B.V. All rights reserved.

p21{sup WAF1/Cip1/Sdi1} knockout mice respond to doxorubicin with reduced cardiotoxicity

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

Terrand, Jerome; Xu, Beibei; Morrissy, Steve

2011-11-15

Doxorubicin (Dox) is an antineoplastic agent that can cause cardiomyopathy in humans and experimental animals. As an inducer of reactive oxygen species and a DNA damaging agent, Dox causes elevated expression of p21{sup WAF1/Cip1/Sdi1} (p21) gene. Elevated levels of p21 mRNA and p21 protein have been detected in the myocardium of mice following Dox treatment. With chronic treatment of Dox, wild type (WT) animals develop cardiomyopathy evidenced by elongated nuclei, mitochondrial swelling, myofilamental disarray, reduced cardiac output, reduced ejection fraction, reduced left ventricular contractility, and elevated expression of ANF gene. In contrast, p21 knockout (p21KO) mice did not show significantmore » changes in the same parameters in response to Dox treatment. In an effort to understand the mechanism of the resistance against Dox induced cardiomyopathy, we measured levels of antioxidant enzymes and found that p21KO mice did not contain elevated basal or inducible levels of glutathione peroxidase and catalase. Measurements of 6 circulating cytokines indicated elevation of IL-6, IL-12, IFN{gamma} and TNF{alpha} in Dox treated WT mice but not p21KO mice. Dox induced elevation of IL-6 mRNA was detected in the myocardium of WT mice but not p21KO mice. While the mechanism of the resistance against Dox induced cardiomyopathy remains unclear, lack of inflammatory response may contribute to the observed cardiac protection in p21KO mice. -- Highlights: Black-Right-Pointing-Pointer Doxorubicin induces p21 elevation in the myocardium. Black-Right-Pointing-Pointer Doxorubicin causes dilated cardiomyopathy in wild type mice. Black-Right-Pointing-Pointer p21 Knockout mice are resistant against doxorubicin induced cardiomyopathy. Black-Right-Pointing-Pointer Lack of inflammatory response correlates with the resistance in p21 knockout mice.« less

The Role of SGLT1 and GLUT2 in Intestinal Glucose Transport and Sensing

PubMed Central

Röder, Pia V.; Geillinger, Kerstin E.; Zietek, Tamara S.; Thorens, Bernard; Koepsell, Hermann; Daniel, Hannelore

2014-01-01

Intestinal glucose absorption is mediated by SGLT1 whereas GLUT2 is considered to provide basolateral exit. Recently, it was proposed that GLUT2 can be recruited into the apical membrane after a high luminal glucose bolus allowing bulk absorption of glucose by facilitated diffusion. Moreover, SGLT1 and GLUT2 are suggested to play an important role in intestinal glucose sensing and incretin secretion. In mice that lack either SGLT1 or GLUT2 we re-assessed the role of these transporters in intestinal glucose uptake after radiotracer glucose gavage and performed Western blot analysis for transporter abundance in apical membrane fractions in a comparative approach. Moreover, we examined the contribution of these transporters to glucose-induced changes in plasma GIP, GLP-1 and insulin levels. In mice lacking SGLT1, tissue retention of tracer glucose was drastically reduced throughout the entire small intestine whereas GLUT2-deficient animals exhibited higher tracer contents in tissue samples than wild type animals. Deletion of SGLT1 resulted also in reduced blood glucose elevations and abolished GIP and GLP-1 secretion in response to glucose. In mice lacking GLUT2, glucose-induced insulin but not incretin secretion was impaired. Western blot analysis revealed unchanged protein levels of SGLT1 after glucose gavage. GLUT2 detected in apical membrane fractions mainly resulted from contamination with basolateral membranes but did not change in density after glucose administration. SGLT1 is unequivocally the prime intestinal glucose transporter even at high luminal glucose concentrations. Moreover, SGLT1 mediates glucose-induced incretin secretion. Our studies do not provide evidence for GLUT2 playing any role in either apical glucose influx or incretin secretion. PMID:24587162

Female Nur77-Deficient Mice Show Increased Susceptibility to Diet-Induced Obesity

PubMed Central

Perez-Sieira, Sonia; Martinez, Gloria; Porteiro, Begoña; Lopez, Miguel; Vidal, Anxo; Nogueiras, Ruben; Dieguez, Carlos

2013-01-01

Adipose tissue is essential in the regulation of body weight. The key process in fat catabolism and the provision of energy substrate during times of nutrient deprivation or enhanced energy demand is the hydrolysis of triglycerides and the release of fatty acids and glycerol. Nur77 is a member of the NR4A subfamily of nuclear receptors that plays an important metabolic role, modulating hepatic glucose metabolism and lipolysis in muscle. However, its endogenous role on white adipose tissue, as well as the gender dependency of these mechanisms, remains largely unknown. Male and female wild type and Nur77 deficient mice were fed with a high fat diet (45% calories from fat) for 4 months. Mice were analyzed in vivo with the indirect calorimetry system, and tissues were analyzed by real-time PCR and Western blot analysis. Female, but not male Nur77 deficient mice, gained more weight and fat mass when compared to wild type mice fed with high fat diet, which can be explained by decreased energy expenditure. The lack of Nur77 also led to a decreased pHSL/HSL ratio in white adipose tissue and increased expression of CIDEA in brown adipose tissue of female Nur77 deficient mice. Overall, these findings suggest that Nur77 is an important physiological modulator of lipid metabolism in adipose tissue and that there are gender differences in the sensitivity to deletion of the Nur77 signaling. The decreased energy expenditure and the actions of Nur77 on liver, muscle, brown and white adipose tissue contribute to the increased susceptibility to diet-induced obesity in females lacking Nur77. PMID:23342015

Jasmonate-dependent modifications of the pectin matrix during potato development function as a defense mechanism targeted by Dickeya dadantii virulence factors.

PubMed

Taurino, Marco; Abelenda, Jose A; Río-Alvarez, Isabel; Navarro, Cristina; Vicedo, Begonya; Farmaki, Theodora; Jiménez, Pedro; García-Agustín, Pilar; López-Solanilla, Emilia; Prat, Salomé; Rojo, Enrique; Sánchez-Serrano, José J; Sanmartín, Maite

2014-02-01

The plant cell wall constitutes an essential protection barrier against pathogen attack. In addition, cell-wall disruption leads to accumulation of jasmonates (JAs), which are key signaling molecules for activation of plant inducible defense responses. However, whether JAs in return modulate the cell-wall composition to reinforce this defensive barrier remains unknown. The enzyme 13-allene oxide synthase (13-AOS) catalyzes the first committed step towards biosynthesis of JAs. In potato (Solanum tuberosum), there are two putative St13-AOS genes, which we show here to be differentially induced upon wounding. We also determine that both genes complement an Arabidopsis aos null mutant, indicating that they encode functional 13-AOS enzymes. Indeed, transgenic potato plants lacking both St13-AOS genes (CoAOS1/2 lines) exhibited a significant reduction of JAs, a concomitant decrease in wound-responsive gene activation, and an increased severity of soft rot disease symptoms caused by Dickeya dadantii. Intriguingly, a hypovirulent D. dadantii pel strain lacking the five major pectate lyases, which causes limited tissue maceration on wild-type plants, regained infectivity in CoAOS1/2 plants. In line with this, we found differences in pectin methyl esterase activity and cell-wall pectin composition between wild-type and CoAOS1/2 plants. Importantly, wild-type plants had pectins with a lower degree of methyl esterification, which are the substrates of the pectate lyases mutated in the pel strain. These results suggest that, during development of potato plants, JAs mediate modification of the pectin matrix to form a defensive barrier that is counteracted by pectinolytic virulence factors from D. dadantii. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

Wild-type and mutant AvrA- Salmonella induce broadly similar immune pathways in the chicken ceca with key differences in signaling intermediates and inflammation.

PubMed

Arsenault, Ryan J; Genovese, Kenneth J; He, Haiqi; Wu, Huixia; Neish, Andrew S; Kogut, Michael H

2016-02-01

Salmonella enterica serovar Typhimurium (ST) is a serious infectious disease throughout the world, and a major reservoir for Salmonella is chicken. Chicken infected with Salmonella do not develop clinical disease, this may be the result of important host interactions with key virulence proteins. To study this, we inoculated chicken with mutant Salmonella Typhimurium that lacked the virulence protein AvrA (AvrA(-)). AvrA is referred to as an avirulence factor, as it moderates the host immune response. The lack of the AvrA virulence gene in ST resulted in reduced weight gain, enhanced persistence and greater extraintestinal organ invasion in chickens, as compared to wild-type (WT) ST. Kinome analysis was performed on inoculated cecal tissue. The majority of the signal transduction pathways induced by AvrA(-) and WT ST were similar; however, we observed alterations in innate immune system signaling. In addition, a leukocyte migration pathway was altered by AvrA(-) ST that may allow greater gut barrier permeability and invasion by the mutant. Cytokine expression did not appear significantly altered at 7 d post-inoculation; at 14 d post-inoculation, there was an observed increase in the expression of anti-inflammatory IL-10 in the WT inoculated ceca. This study is the first to describe mutant AvrA(-) ST infection of chicken and provides further insight into the Salmonella responses observed in chicken relative to other species such as humans and cattle. Published by Oxford University Press on behalf of Poultry Science Association 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Lack of vasopressin does not prevent the behavioural and endocrine changes induced by chronic unpredictable stress.

PubMed

Varga, János; Domokos, Agnes; Barna, István; Jankord, Ryan; Bagdy, György; Zelena, Dóra

2011-01-15

Vasopressin (VP) plays an important role in hypothalamo-pituitary-adrenal (HPA) axis regulation and in stress-related disorders. Our previous studies confirmed the role of VP in acute situations, where VP-deficient Brattleboro rats had less depression-like behaviour compared to animals that express VP. In this study, we test the hypothesis that VP-deficient rats are more resistant to the development of chronic HPA axis hyperactivity and depression-like symptoms after chronic unpredictable stress (CUS). Male VP-deficient Brattleboro rats were compared to their heterozygous littermates (controls). CUS consisted of different mild stimuli for 5 weeks. Elevated plus maze and forced swim test were used for behavioural characterization, while organs and blood for HPA axis parameters were collected at the end of the experiment. In controls, CUS resulted in the development of chronic stress state characterized by typical somatic (body weight reduction, thymus involution) and endocrine changes (resting plasma ACTH and corticosterone elevation and POMC mRNA elevation in anterior lobe of the pituitary). Floating time in the forced swim test was enhanced together with reduced open arm entries on elevated plus maze and a reduction in daily food intake. Unexpectedly, the lack of VP did not alter the effect of CUS on the somatic and behavioural measures, but only prevented CUS-induced corticosterone changes. In conclusion, lifelong VP-deficiency has a positive effect on corticosterone elevation following CUS but does not affect the behavioural consequences of CUS. It is likely that the interplay of several related factors, rather than an alteration in a single neuropeptide, modulates behaviour and disease pathogenesis. Copyright © 2010 Elsevier Inc. All rights reserved.

EGF stimulates the activation of EGF receptors and the selective activation of major signaling pathways during mitosis.

PubMed

Wee, Ping; Shi, Huaiping; Jiang, Jennifer; Wang, Yuluan; Wang, Zhixiang

2015-03-01

Mitosis and epidermal growth factor (EGF) receptor (EGFR) are both targets for cancer therapy. The role of EGFR signaling in mitosis has been rarely studied and poorly understood. The limited studies indicate that the activation of EGFR and downstream signaling pathways is mostly inhibited during mitosis. However, we recently showed that EGFR is phosphorylated in response to EGF stimulation in mitosis. Here we studied EGF-induced EGFR activation and the activation of major signaling pathways downstream of EGFR during mitosis. We showed that EGFR was strongly activated by EGF during mitosis as all the five major tyrosine residues including Y992, Y1045, Y1068, Y1086, and Y1173 were phosphorylated to a level similar to that in the interphase. We further showed that the activated EGFR is able to selectively activate some downstream signaling pathways while avoiding others. Activated EGFR is able to activate PI3K and AKT2, but not AKT1, which may be responsible for the observed effects of EGF against nocodazole-induced cell death. Activated EGFR is also able to activate c-Src, c-Cbl and PLC-γ1 during mitosis. However, activated EGFR is unable to activate ERK1/2 and their downstream substrates RSK and Elk-1. While it activated Ras, EGFR failed to fully activate Raf-1 in mitosis due to the lack of phosphorylation at Y341 and the lack of dephosphorylation at pS259. We conclude that contrary to the dogma, EGFR is activated by EGF during mitosis. Moreover, EGFR-mediated cell signaling is regulated differently from the interphase to specifically serve the needs of the cell in mitosis. Copyright © 2015 Elsevier Inc. All rights reserved.

Functional significance of the intermediate conductance Ca2+-activated K+ channel for the short-term survival of injured erythrocytes.

PubMed

Föller, Michael; Bobbala, Diwakar; Koka, Saisudha; Boini, Krishna M; Mahmud, Hasan; Kasinathan, Ravi S; Shumilina, Ekaterina; Amann, Kerstin; Beranek, Golo; Sausbier, Ulrike; Ruth, Peter; Sausbier, Matthias; Lang, Florian; Huber, Stephan M

2010-11-01

Increased cytosolic Ca(2+) concentrations activate Gardos K(+) channels in human erythrocytes with membrane hyperpolarization, efflux of K(+), Cl⁻, and osmotically obliged H₂O resulting in cell shrinkage, a phenomenon referred to as Gardos effect. We tested whether the Gardos effect delays colloid osmotic hemolysis of injured erythrocytes from mice lacking the Ca(2+)-activated K(+) channel K(Ca)3.1. To this end, we applied patch clamp and flow cytometry and determined in vitro as well as in vivo hemolysis. As a result, erythrocytes from K(Ca)3.1-deficient (K(Ca)3.1(-/-)) mice lacked Gardos channel activity and the Gardos effect. Blood parameters, reticulocyte count, or osmotic erythrocyte resistance, however, did not differ between K(Ca)3.1(-/-) mice and their wild-type littermates, suggesting low or absent Gardos channel activity in unstressed erythrocytes. Oxidative stress-induced Ca(2+) entry and phospholipid scrambling were significantly less pronounced in K(Ca)3.1(-/-) than in wild-type erythrocytes. Moreover, in vitro treatment with α-toxin from Staphylococcus aureus, which forms pores in the cellular membrane, resulted in significantly stronger hemolysis of K(Ca)3.1(-/-) than of wild-type erythrocytes. Intravenous injection of α-toxin induced more profound hemolysis in K(Ca)3.1(-/-) than in wild-type mice. Similarly, intra-peritoneal application of the redox-active substance phenylhydrazine, an agent for the induction of hemolytic anemia, was followed by a significantly stronger decrease of hematocrit in K(Ca)3.1(-/-) than in wild-type mice. Finally, malaria infection triggered the activation of K(Ca)3.1 and transient shrinkage of the infected erythrocytes. In conclusion, K(Ca)3.1 channel activity and Gardos effect counteract hemolysis of injured erythrocytes, thus decreasing hemoglobin release into circulating blood.

Structural characterization of more potent alternatives to HAMLET, a tumoricidal complex of α-lactalbumin and oleic acid.

PubMed

Nemashkalova, Ekaterina L; Kazakov, Alexei S; Khasanova, Leysan M; Permyakov, Eugene A; Permyakov, Sergei E

2013-09-10

HAMLET is a complex of human α-lactalbumin (hLA) with oleic acid (OA) that kills various tumor cells and strains of Streptococcus pneumoniae. More potent protein-OA complexes were previously reported for bovine α-lactalbumin (bLA) and β-lactoglobulin (bLG), and pike parvalbumin (pPA), and here we explore their structural features. The concentration dependencies of the tryptophan fluorescence of hLA, bLA, and bLG complexes with OA reveal their disintegration at protein concentrations below the micromolar level. Chemical cross-linking experiments provide evidence that association with OA shifts the distribution of oligomeric forms of hLA, bLA, bLG, and pPA toward higher-order oligomers. This effect is confirmed for bLA and bLG using the dynamic light scattering method, while pPA is shown to associate with OA vesicles. Like hLA binding, OA binding increases the affinity of bLG for small unilamellar dipalmitoylphosphatidylcholine vesicles, while pPA efficiently binds to the vesicles irrespective of OA binding. The association of OA with bLG and pPA increases their α-helix and cross-β-sheet content and resistance to enzymatic proteolysis, which is indicative of OA-induced protein structuring. The lack of excess heat sorption during melting of bLG and pPA in complex with OA and the presence of a cooperative thermal transition at the level of their secondary structure suggest that the OA-bound forms of bLG and pPA lack a fixed tertiary structure but exhibit a continuous thermal transition. Overall, despite marked differences, the HAMLET-like complexes that were studied exhibit a common feature: a tendency toward protein oligomerization. Because OA-induced oligomerization has been reported for other proteins, this phenomenon is inherent to many proteins.

Dopamine D3 receptor knockout mice exhibit abnormal nociception in a sex-different manner.

PubMed

Liu, Peng; Xing, Bo; Chu, Zheng; Liu, Fei; Lei, Gang; Zhu, Li; Gao, Ya; Chen, Teng; Dang, Yong-Hui

2017-07-01

Pain is a complex and subjective experience. Previous studies have shown that mice lacking the dopamine D3 receptor (D3RKO) exhibit hypoalgesia, indicating a role of the D3 receptor in modulation of nociception. Given that there are sex differences in pain perception, there may be differences in responses to nociceptive stimuli between male and female D3RKO mice. In the current study, we examined the role of the D3 receptor in modulating nociception in male and female D3RKO mice. Acute thermal pain was modeled by hot-plate test. This test was performed at different temperatures including 52°C, 55°C, and 58°C. The von Frey hair test was applied to evaluate mechanical pain. And persistent pain produced by peripheral tissue injury and inflammation was modeled by formalin test. In the hot-plate test, compared with wild-type (WT) mice, D3RKO mice generally exhibited longer latencies at each of the three temperatures. Specially, male D3RKO mice showed hypoalgesia compared with male WT mice when the temperature was 55°C, while for the female mice, there was a statistical difference between genotypes when the test condition was 52°C. In the von Frey hair test, both male and female D3RKO mice exhibited hypoalgesia. In the formalin test, the male D3RKO mice displayed a similar nociceptive behavior as their sex-matched WT littermates, whereas significantly depressed late-phase formalin-induced nociceptive behaviors were observed in the female mutants. These findings indicated that the D3 receptor affects nociceptive behaviors in a sex-specific manner and that its absence induces more analgesic behavior in the female knockout mice. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Optimizing Multi-Station Template Matching to Identify and Characterize Induced Seismicity in Ohio

NASA Astrophysics Data System (ADS)

Brudzinski, M. R.; Skoumal, R.; Currie, B. S.

2014-12-01

As oil and gas well completions utilizing multi-stage hydraulic fracturing have become more commonplace, the potential for seismicity induced by the deep disposal of frac-related flowback waters and the hydraulic fracturing process itself has become increasingly important. While it is rare for these processes to induce felt seismicity, the recent increase in the number of deep injection wells and volumes injected have been suspected to have contributed to a substantial increase of events = M 3 in the continental U.S. over the past decade. Earthquake template matching using multi-station waveform cross-correlation is an adept tool for investigating potentially induced sequences due to its proficiency at identifying similar/repeating seismic events. We have sought to refine this approach by investigating a variety of seismic sequences and determining the optimal parameters (station combinations, template lengths and offsets, filter frequencies, data access method, etc.) for identifying induced seismicity. When applied to a sequence near a wastewater injection well in Youngstown, Ohio, our optimized template matching routine yielded 566 events while other template matching studies found ~100-200 events. We also identified 77 events on 4-12 March 2014 that are temporally and spatially correlated with active hydraulic fracturing in Poland Township, Ohio. We find similar improvement in characterizing sequences in Washington and Harrison Counties, which appear to be related to wastewater injection and hydraulic fracturing, respectively. In the Youngstown and Poland Township cases, focal mechanisms and double difference relocation using the cross-correlation matrix finds left-lateral faults striking roughly east-west near the top of the basement. We have also used template matching to determine isolated earthquakes near several other wastewater injection wells are unlikely to be induced based on a lack of similar/repeating sequences. Optimized template matching utilizes high-quality reliable stations within pre-existing seismic networks and is therefore a cost-efficient monitoring strategy for identifying and characterizing potentially induced seismic sequences.

An Alternative Splice Product of IκB Kinase (IKKγ), IKKγ-Δ, Differentially Mediates Cytokine and Human T-Cell Leukemia Virus Type 1 Tax-Induced NF-κB Activation

PubMed Central

Hai, Tao; Yeung, Man-Lung; Wood, Thomas G.; Wei, Yuanfen; Yamaoka, Shoji; Gatalica, Zoran; Jeang, Kuan-Teh; Brasier, Allan R.

2006-01-01

NF-κB is an inducible transcription factor mediating innate immune responses whose activity is controlled by the multiprotein IκB kinase (IKK) “signalsome”. The core IKK consists of two catalytic serine kinases, IKKα and IKKβ, and a noncatalytic subunit, IKKγ. IKKγ is required for IKK activity by mediating kinase oligomerization and serving to couple the core catalytic subunits to upstream mitogen-activated protein 3-kinase cascades. We have discovered an alternatively spliced IKKγ mRNA isoform, encoding an in-frame deletion of exon 5, termed IKKγ-Δ. Using a specific reverse transcription-PCR assay, we find that IKKγ-Δ is widely expressed in cultured human cells and normal human tissues. Because IKKγ-Δ protein is lacking a critical coiled-coil domain important in protein-protein interactions, we sought to determine its signaling properties by examining its ability to self associate, couple to activators of the canonical pathway, and mediate human T-cell leukemia virus type 1 (HTLV-1) Tax-induced NF-κB activity. Coimmunoprecipitation and confocal colocalization assays indicate IKKγ-Δ has strong homo- and heterotypic association with wild-type (WT) IKKγ and, like IKKγ WT, associates with the IKKβ kinase. Similarly, IKKγ-Δ mediates IKK kinase activity and downstream NF-κB-dependent transcription in response to tumor necrosis factor (TNF) and the NF-κB-inducing kinase-IKKα signaling pathway. Surprisingly, however, in contrast to IKKγ WT, IKKγ-Δ is not able to mediate HTLV-1 Tax-induced NF-κB-dependent transcription, even though IKKγ-Δ binds and colocalizes with Tax. These observations suggest that IKKγ-Δ is a functionally distinct alternatively spliced mRNA product differentially mediating TNF-induced, but not Tax-induced, signals converging on the IKK signalsome. Differing levels of IKKγ-Δ expression, therefore, may affect signal transduction cascades coupling to IKK. PMID:16611882

Genetic deletion of the P2Y2 receptor offers significant resistance to development of lithium-induced polyuria accompanied by alterations in PGE2 signaling.

PubMed

Zhang, Yue; Pop, Ioana L; Carlson, Noel G; Kishore, Bellamkonda K

2012-01-01

Lithium (Li)-induced polyuria is due to resistance of the medullary collecting duct (mCD) to the action of arginine vasopressin (AVP), apparently mediated by increased production of PGE(2). We previously reported that the P2Y(2) receptor (P2Y(2)-R) antagonizes the action of AVP on the mCD and may play a role in Li-induced polyuria by enhancing the production of PGE(2) in mCD. Hence, we hypothesized that genetic deletion of P2Y(2)-R should ameliorate Li-induced polyuria. Wild-type (WT) or P2Y(2)-R knockout (KO) mice were fed normal or Li-added diets for 14 days and euthanized. Li-induced polyuria, and decreases in urine osmolality and AQP2 protein abundance in the renal medulla, were significantly less compared with WT mice despite the lack of differences in Li intake or terminal serum or inner medullary tissue Li levels. Li-induced increased urinary excretion of PGE(2) was not affected in KO mice. However, prostanoid EP(3) receptor (EP3-R) protein abundance in the renal medulla of KO mice was markedly lower vs. WT mice, irrespective of the dietary regimen. The protein abundances of other EP-Rs were not altered across the groups irrespective of the dietary regimen. Ex vivo stimulation of mCD with PGE(2) generated significantly more cAMP in Li-fed KO mice (130%) vs. Li-fed WT mice (100%). Taken together, these data suggest 1) genetic deletion of P2Y(2)-R offers significant resistance to the development of Li-induced polyuria; and 2) this resistance is apparently due to altered PGE(2) signaling mediated by a marked decrease in EP3-R protein abundance in the medulla, thus attenuating the EP3-mediated decrease in cAMP levels in mCD.

Rapid generation of mitochondrial superoxide induces mitochondrion-dependent but caspase-independent cell death in hippocampal neuronal cells that morphologically resembles necroptosis

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

Fukui, Masayuki; Choi, Hye Joung; Zhu, Bao Ting, E-mail: BTZhu@kumc.edu

Studies in recent years have revealed that excess mitochondrial superoxide production is an important etiological factor in neurodegenerative diseases, resulting from oxidative modifications of cellular lipids, proteins, and nucleic acids. Hence, it is important to understand the mechanism by which mitochondrial oxidative stress causes neuronal death. In this study, the immortalized mouse hippocampal neuronal cells (HT22) in culture were used as a model and they were exposed to menadione (also known as vitamin K{sub 3}) to increase intracellular superoxide production. We found that menadione causes preferential accumulation of superoxide in the mitochondria of these cells, along with the rapid developmentmore » of mitochondrial dysfunction and cellular ATP depletion. Neuronal death induced by menadione is independent of the activation of the MAPK signaling pathways and caspases. The lack of caspase activation is due to the rapid depletion of cellular ATP. It was observed that two ATP-independent mitochondrial nucleases, namely, AIF and Endo G, are released following menadione exposure. Silencing of their expression using specific siRNAs results in transient suppression (for ∼ 12 h) of mitochondrial superoxide-induced neuronal death. While suppression of the mitochondrial superoxide dismutase expression markedly sensitizes neuronal cells to mitochondrial superoxide-induced cytotoxicity, its over-expression confers strong protection. Collectively, these findings showed that many of the observed features associated with mitochondrial superoxide-induced cell death, including caspase independency, rapid depletion of ATP level, mitochondrial release of AIF and Endo G, and mitochondrial swelling, are distinctly different from those of apoptosis; instead they resemble some of the known features of necroptosis. -- Highlights: ► Menadione causes mitochondrial superoxide accumulation and injury. ► Menadione-induced cell death is caspase-independent, due to rapid depletion of ATP. ► The release of AIF and Endo G contributes importantly to cell death. ► Alterations of SOD1 or SOD2 levels alter menadione-induced neuronal cytotoxicity.« less

Aeromonas Caviae Strain Induces Th1 Cytokine Response in Mouse Intestinal Tract

EPA Science Inventory

Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus. Microarray profiling of murine small i...

Aeromonas caviae strain induces Th1 cytokine response in mouse intestinal tract

EPA Science Inventory

Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus,. Microarray profiling of...

Expression and purification of recombinant tung tree diacylglycerol acyltransferase 2

USDA-ARS?s Scientific Manuscript database

Diacylglycerol acyltransferases (DGATs) catalyze the last step of triacylglycerol (TAG) biosynthesis in eukaryotic organisms. Plants and animals deficient in DGATs accumulate less TAG. Over-expression of DGATs increases TAG. DGAT knockout mice are resistant to diet-induced obesity and lack milk secr...

Re: Traumatic Cardiorespiratory Arrest on the Battlefield

DTIC Science & Technology

2013-08-01

Military Surgery and Trauma Royal Centre for Defence Medicine Birmingham, United Kingdom Henrietta Poon, MRCS Todd E. Rasmussen, MD US Army Institute...because they will need surgery urgently. One could question whether respiratory acidosis by lack of intubation outweighs the effects induced by MV in

SELECTIVE TRACE ENRICHMENT BY IMMUNOAFFINITY CAPILLARY ELECTROCHROMATOGRAPHY ON-LINE WITH CAPILLARY ZONE ELECTROPHORESIS - LASER-INDUCED FLUORESCENCE

EPA Science Inventory

Limited by the lack of a sensitive, universal detector, many capillary-based liquid-phase separation techniques might benefit from techniques that overcome modest concentration sensitivity by preconcentrating large injection volumes. The work presented employs selective solid-ph...

Adipose Tissue CLK2 Promotes Energy Expenditure during High-Fat Diet Intermittent Fasting.

PubMed

Hatting, Maximilian; Rines, Amy K; Luo, Chi; Tabata, Mitsuhisa; Sharabi, Kfir; Hall, Jessica A; Verdeguer, Francisco; Trautwein, Christian; Puigserver, Pere

2017-02-07

A promising approach to treating obesity is to increase diet-induced thermogenesis in brown adipose tissue (BAT), but the regulation of this process remains unclear. Here we find that CDC-like kinase 2 (CLK2) is expressed in BAT and upregulated upon refeeding. Mice lacking CLK2 in adipose tissue exhibit exacerbated obesity and decreased energy expenditure during high-fat diet intermittent fasting. Additionally, tissue oxygen consumption and protein levels of UCP1 are reduced in CLK2-deficient BAT. Phosphorylation of CREB, a transcriptional activator of UCP1, is markedly decreased in BAT cells lacking CLK2 due to enhanced CREB dephosphorylation. Mechanistically, CREB dephosphorylation is rescued by the inhibition of PP2A, a phosphatase that targets CREB. Our results suggest that CLK2 is a regulatory component of diet-induced thermogenesis in BAT through increased CREB-dependent expression of UCP1. Copyright © 2017 Elsevier Inc. All rights reserved.

Trans-synaptic zinc mobilization improves social interaction in two mouse models of autism through NMDAR activation.

PubMed

Lee, Eun-Jae; Lee, Hyejin; Huang, Tzyy-Nan; Chung, Changuk; Shin, Wangyong; Kim, Kyungdeok; Koh, Jae-Young; Hsueh, Yi-Ping; Kim, Eunjoon

2015-05-18

Genetic aspects of autism spectrum disorders (ASDs) have recently been extensively explored, but environmental influences that affect ASDs have received considerably less attention. Zinc (Zn) is a nutritional factor implicated in ASDs, but evidence for a strong association and linking mechanism is largely lacking. Here we report that trans-synaptic Zn mobilization rapidly rescues social interaction in two independent mouse models of ASD. In mice lacking Shank2, an excitatory postsynaptic scaffolding protein, postsynaptic Zn elevation induced by clioquinol (a Zn chelator and ionophore) improves social interaction. Postsynaptic Zn is mainly derived from presynaptic pools and activates NMDA receptors (NMDARs) through postsynaptic activation of the tyrosine kinase Src. Clioquinol also improves social interaction in mice haploinsufficient for the transcription factor Tbr1, which accompanies NMDAR activation in the amygdala. These results suggest that trans-synaptic Zn mobilization induced by clioquinol rescues social deficits in mouse models of ASD through postsynaptic Src and NMDAR activation.

Norepinephrine is required to promote wakefulness and for hypocretin-induced arousal in zebrafish

PubMed Central

Singh, Chanpreet; Oikonomou, Grigorios; Prober, David A

2015-01-01

Pharmacological studies in mammals suggest that norepinephrine (NE) plays an important role in promoting arousal. However, the role of endogenous NE is unclear, with contradicting reports concerning the sleep phenotypes of mice lacking NE due to mutation of dopamine β-hydroxylase (dbh). To investigate NE function in an alternative vertebrate model, we generated dbh mutant zebrafish. In contrast to mice, these animals exhibit dramatically increased sleep. Surprisingly, despite an increase in sleep, dbh mutant zebrafish have a reduced arousal threshold. These phenotypes are also observed in zebrafish treated with small molecules that inhibit NE signaling, suggesting that they are caused by the lack of NE. Using genetic overexpression of hypocretin (Hcrt) and optogenetic activation of hcrt-expressing neurons, we also find that NE is important for Hcrt-induced arousal. These results establish a role for endogenous NE in promoting arousal and indicate that NE is a critical downstream effector of Hcrt neurons. DOI: http://dx.doi.org/10.7554/eLife.07000.001 PMID:26374985

Low hypoxia inducible factor-1α (HIF-1α) expression in testicular germ cell tumors - a major reason for enhanced chemosensitivity?

PubMed

Shenoy, Niraj; Dronca, Roxana; Quevedo, Fernando; Boorjian, Stephen A; Cheville, John; Costello, Brian; Kohli, Manish; Witzig, Thomas; Pagliaro, Lance

2017-08-01

The molecular basis for enhanced chemosensitivity of testicular germ cell tumors (GCT) has been an area of great interest, as it could potentially give us therapeutic leads in other resistant malignancies. Thus far, however, the increased sensitivity of GCT has been variously attributed to multiple factors - an inability to detoxify cisplatin, a lack of export pumps, an inability to repair the DNA damage, an intact apoptotic cascade and lack of p53 mutation; but a unifying underlying etiology leading to the aforementioned processes and having a translational implication has so far been elusive. Herein, we offer evidence to support a potential significant role for the previously demonstrated low hypoxia inducible factor-1α (HIF-1α) expression in mediating the general exquisite chemosensitivity of testicular GCT, through the aforementioned processes. This molecular mechanism based hypothesis could have a significant translational implication in platinum refractory GCT as well as other platinum resistant malignancies.

Learning induces the translin/trax RNase complex to express activin receptors for persistent memory.

PubMed

Park, Alan Jung; Havekes, Robbert; Fu, Xiuping; Hansen, Rolf; Tudor, Jennifer C; Peixoto, Lucia; Li, Zhi; Wu, Yen-Ching; Poplawski, Shane G; Baraban, Jay M; Abel, Ted

2017-09-20

Long-lasting forms of synaptic plasticity and memory require de novo protein synthesis. Yet, how learning triggers this process to form memory is unclear. Translin/trax is a candidate to drive this learning-induced memory mechanism by suppressing microRNA-mediated translational silencing at activated synapses. We find that mice lacking translin/trax display defects in synaptic tagging, which requires protein synthesis at activated synapses, and long-term memory. Hippocampal samples harvested from these mice following learning show increases in several disease-related microRNAs targeting the activin A receptor type 1C (ACVR1C), a component of the transforming growth factor-β receptor superfamily. Furthermore, the absence of translin/trax abolishes synaptic upregulation of ACVR1C protein after learning. Finally, synaptic tagging and long-term memory deficits in mice lacking translin/trax are mimicked by ACVR1C inhibition. Thus, we define a new memory mechanism by which learning reverses microRNA-mediated silencing of the novel plasticity protein ACVR1C via translin/trax.

Hematopoietic Kit Deficiency, rather than Lack of Mast Cells, Protects Mice from Obesity and Insulin Resistance.

PubMed

Gutierrez, Dario A; Muralidhar, Sathya; Feyerabend, Thorsten B; Herzig, Stephan; Rodewald, Hans-Reimer

2015-05-05

Obesity, insulin resistance, and related pathologies are associated with immune-mediated chronic inflammation. Kit mutant mice are protected from diet-induced obesity and associated co-morbidities, and this phenotype has previously been attributed to their lack of mast cells. We performed a comprehensive metabolic analysis of Kit-dependent Kit(W/Wv) and Kit-independent Cpa3(Cre/+) mast-cell-deficient mouse strains, employing diet-induced or genetic (Lep(Ob/Ob) background) models of obesity. Our results show that mast cell deficiency, in the absence of Kit mutations, plays no role in the regulation of weight gain or insulin resistance. Moreover, we provide evidence that the metabolic phenotype observed in Kit mutant mice, while independent of mast cells, is immune regulated. Our data underscore the value of definitive mast cell deficiency models to conclusively test the involvement of this enigmatic cell in immune-mediated pathologies and identify Kit as a key hematopoietic factor in the pathogenesis of metabolic syndrome. Copyright © 2015 Elsevier Inc. All rights reserved.

Multiscale Evaluation of Thermal Dependence in the Glucocorticoid Response of Vertebrates.

PubMed

Jessop, Tim S; Lane, Meagan L; Teasdale, Luisa; Stuart-Fox, Devi; Wilson, Robbie S; Careau, Vincent; Moore, Ignacio T

2016-09-01

Environmental temperature has profound effects on animal physiology, ecology, and evolution. Glucocorticoid (GC) hormones, through effects on phenotypic performance and life history, provide fundamental vertebrate physiological adaptations to environmental variation, yet we lack a comprehensive understanding of how temperature influences GC regulation in vertebrates. Using field studies and meta- and comparative phylogenetic analyses, we investigated how acute change and broadscale variation in temperature correlated with baseline and stress-induced GC levels. Glucocorticoid levels were found to be temperature and taxon dependent, but generally, vertebrates exhibited strong positive correlations with acute changes in temperature. Furthermore, reptile baseline, bird baseline, and capture stress-induced GC levels to some extent covaried with broadscale environmental temperature. Thus, vertebrate GC function appears clearly thermally influenced. However, we caution that lack of detailed knowledge of thermal plasticity, heritability, and the basis for strong phylogenetic signal in GC responses limits our current understanding of the role of GC hormones in species' responses to current and future climate variation.

Branched-chain amino acid supplementation promotes aerobic growth of Salmonella Typhimurium under nitrosative stress conditions.

PubMed

Park, Yoon Mee; Lee, Hwa Jeong; Jeong, Jae-Ho; Kook, Joong-Ki; Choy, Hyon E; Hahn, Tae-Wook; Bang, Iel Soo

2015-12-01

Nitric oxide (NO) inactivates iron-sulfur enzymes in bacterial amino acid biosynthetic pathways, causing amino acid auxotrophy. We demonstrate that exogenous supplementation with branched-chain amino acids (BCAA) can restore the NO resistance of hmp mutant Salmonella Typhimurium lacking principal NO-metabolizing enzyme flavohemoglobin, and of mutants further lacking iron-sulfur enzymes dihydroxy-acid dehydratase (IlvD) and isopropylmalate isomerase (LeuCD) that are essential for BCAA biosynthesis, in an oxygen-dependent manner. BCAA supplementation did not affect the NO consumption rate of S. Typhimurium, suggesting the BCAA-promoted NO resistance independent of NO metabolism. BCAA supplementation also induced intracellular survival of ilvD and leuCD mutants at wild-type levels inside RAW 264.7 macrophages that produce constant amounts of NO regardless of varied supplemental BCAA concentrations. Our results suggest that the NO-induced BCAA auxotrophy of Salmonella, due to inactivation of iron-sulfur enzymes for BCAA biosynthesis, could be rescued by bacterial taking up exogenous BCAA available in oxic environments.

DNA polymerase η modulates replication fork progression and DNA damage responses in platinum-treated human cells

NASA Astrophysics Data System (ADS)

Sokol, Anna M.; Cruet-Hennequart, Séverine; Pasero, Philippe; Carty, Michael P.

2013-11-01

Human cells lacking DNA polymerase η (polη) are sensitive to platinum-based cancer chemotherapeutic agents. Using DNA combing to directly investigate the role of polη in bypass of platinum-induced DNA lesions in vivo, we demonstrate that nascent DNA strands are up to 39% shorter in human cells lacking polη than in cells expressing polη. This provides the first direct evidence that polη modulates replication fork progression in vivo following cisplatin and carboplatin treatment. Severe replication inhibition in individual platinum-treated polη-deficient cells correlates with enhanced phosphorylation of the RPA2 subunit of replication protein A on serines 4 and 8, as determined using EdU labelling and immunofluorescence, consistent with formation of DNA strand breaks at arrested forks in the absence of polη. Polη-mediated bypass of platinum-induced DNA lesions may therefore represent one mechanism by which cancer cells can tolerate platinum-based chemotherapy.

Characterization of a hypoallergenic wheat line lacking ω-5 gliadin.

PubMed

Kohno, Kunie; Takahashi, Hitoshi; Endo, Takashi R; Matsuo, Hiroaki; Shiwaku, Kuninori; Morita, Eishin

2016-10-01

There is no curative treatment for wheat-dependent exercise-induced anaphylaxis (WDEIA). ω-5 Gliadin is one of the dominant allergens affecting WDEIA patients. The use of ω-5 gliadin-free wheat flour in the regular diet is considered one of the prophylactic approaches against the elicitation of allergic symptoms and sensitization to ω-5 gliadin. We sought to find hypoallergenic bread wheat (or common wheat) that lacked the genes encoding ω-5 gliadin and to evaluate its in vitro allergenicity. We also aimed to evaluate the sensitization ability of one of the selected hypoallergenic wheat lines by using a possible animal model of wheat allergy. We screened the deletion lines of bread wheat by western blotting to ascertain common wheat lines lacking the ω-5 gliadin locus. The deletion lines we used have partial deficiency of chromosome 1B (Endo and Gill, 1996). To assess sensitization ability of gluten from the selected deletion line, guinea pigs were fed with either the gluten from the selected deletion line or commercially available gluten, and allergic score was evaluated after challenging the same gluten preparations. We found that a deletion line 1BS-18 had the least deficiency of chromosome 1B among the deletion stocks lacking the ω-5 gliadin locus. The challenge test using the guinea pigs revealed that the symptoms induced by application of the 1BS-18 gluten were much less than that of commercially available gluten. The deletion line 1BS-18, which lacked the ω-5 gliadin locus, is likely to have a low sensitization capacity in the guinea pig. The use of the wheat products of the 1BS-18 line in daily life may provide a feasible solution for the onset of wheat allergy. Copyright © 2016 Japanese Society of Allergology. Production and hosting by Elsevier B.V. All rights reserved.

Volatile-Mediated within-Plant Signaling in Hybrid Aspen: Required for Systemic Responses.

PubMed

Li, Tao; Blande, James D

2017-04-01

Plant volatiles play crucial roles in signaling between plants and their associated community members, but their role in within-plant signaling remains largely unexplored, particularly under field conditions. Using a system comprising the hybrid aspen (Populus tremula x tremuloides) and the specialized herbivorous leaf beetle (Phratora laticollis) and, combining field, greenhouse and laboratory experiments, we examined whether local damage triggered systemic responses in undamaged branches that lack vascular connection to the damaged branches, and to what extent this was caused by airborne volatile signals versus internal signals. An experiment tracing dye through the vasculature of saplings revealed no downward movement of the dye from upper to lower branches, suggesting a lack of vascular connectivity among branches. However, we found under both field and laboratory conditions that herbivore feeding on upper branches elicited volatile emissions by undamaged lower branches. Greenhouse experiments manipulating air contact between damaged and undamaged branches showed that systemic induction of volatiles was almost eliminated when air contact was interrupted. Our findings clearly demonstrate that herbivore-induced volatiles overcome vascular constraints and mediate within-plant signaling. Further, we found that volatile signaling led to induction of different classes of volatiles under field and environment controlled conditions, with a weaker response observed in the field. This difference not only reflects the dose- and time-dependent nature of volatile signaling, but also points out that future studies should focus more on field observations to better understand the ecological role of volatile-mediated within-plant signaling.

Disruption of NAD(P)H:quinone oxidoreductase 1 gene in mice leads to radiation induced myeloproliferative disease

PubMed Central

Iskander, Karim; Barrios, Roberto J.; Jaiswal, Anil K.

2008-01-01

NAD(P)H:quinone oxidoreductase1-null (NQO1-/-) mice exposed to 3 grays of γ-radiation demonstrated an increase in neutrophils, bone marrow hypercellularity, and enlarged lymph nodes and spleen. The spleen showed disrupted follicular structure, loss of red pulp, and granulocyte and megakarocyte invasion. Blood and histological analysis did not show any sign of infection in mice. These results suggested that exposure of NQO1-/- mice to γ-radiation led to myeloproliferative disease. Radiation-induced myeloproliferative disease was observed in 74% of NQO1-/- mice as compared to none in wild type mice. NQO1-/- mice exposed to γ-radiation also demonstrated tissues lymphoma (32%) and lung adenocarcinoma (84%). In contrast, only 11% wild type mice showed lymphoma and none showed lung adenocarcinoma. Exposure of NQO1-/- mice to γ-radiation resulted in reduced apoptosis in granulocytes and lack of induction of p53, p21, and Bax. NQO1-/- mice also demonstrated increased expression of myeloid differentiation factors C/EBPα and Pu.1. Intriguingly, exposure of NQO1-/- mice to γ-radiation failed to induce C/EBPα and Pu.1, as was observed in wild type mice. These results suggest that decreased p53/apoptosis and increased Pu.1 and C/EBPα led to myeloid hyperplasia in NQO1-/- mice. The lack of induction of apoptosis and differentiation contributed to radiation-induced myeloproliferative disease in NQO1-/- mice. PMID:18829548