Note: This page contains sample records for the topic vivo luteal function from Science.gov.
While these samples are representative of the content of Science.gov,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of Science.gov
to obtain the most current and comprehensive results.
Last update: November 12, 2013.
1

EFFECTS OF BROMODICHLOROMETHANE (BDCM) ON EX VIVO LUTEAL FUNCTION IN THE F344 RAT DURING PREGNANCY  

EPA Science Inventory

Effects of Bromodichloromethane (BDCM) on Ex Vivo Luteal Function In the Pregnant F344 Rat Susan R. Bielmeier1, Ashley S. Murr2, Deborah S. Best2, Jerome M. Goldman2, and Michael G. Narotsky2 1Curriculum in Toxicology, Univ. of North Carolina, Chapel Hill, NC 27599,...

2

Effects of prostaglandin E and F receptor agonists in vivo on luteal function in ewes.  

PubMed

Loss of progesterone secretion at the end of the estrous cycle is via uterine PGF(2alpha) secretion; however, uterine PGF(2alpha) is not decreased during early pregnancy in ewes to prevent luteolysis. Instead the embryo imparts resistance to PGF(2alpha)-induced luteolysis, which is via the 2-fold increase in prostaglandins E(1) and E(2) (PGE(1), PGE(2); PGE) in the endometrium during early pregnancy. Chronic intrauterine infusion of PGE(1) or PGE(2) prevents spontaneous or an estradiol-17beta, IUD, or PGF(2alpha)-induced luteolysis. Four PGE receptor subtypes (EP(1), EP(2), EP(3), and EP(4)) and an FP receptor specific for PGF(2alpha) have been identified. The objective of this experiment was to determine the effects of EP(1), EP(2), EP(3), or FP receptor agonists in vivo on luteal mRNA for LH receptors, occupied and unoccupied LH receptors, and circulating progesterone in ewes. Ewes received a single treatment of 17-phenyl-tri-Nor-PGE(2) (EP(1), EP(3)), butaprost (EP(2)), 19-(R)-OH-PGE(2) (EP(2)), sulprostone (EP(1), EP(3)), or PGF(2alpha) (FP) receptor agonists into the interstitial tissue of the ovarian vascular pedicle adjacent to the luteal-containing ovary. 17-Phenlyl-tri-Nor-PGE(2) had no effect (P> or =0.05) on any parameter analyzed. Butaprost and 19-(R)-OH-PGE(2) increased (P< or =0.05) mRNA for LH receptors, occupied and unoccupied LH receptors, and circulating progesterone. Both sulprostone and PGF(2alpha) decreased (P< or =0.05) mRNA for LH receptors, occupied and unoccupied LH receptors, and circulating progesterone. It is concluded that both EP(3) and FP receptors may be involved in luteolysis. In addition, EP(2) receptors may mediate prevention of luteolysis via regulation of luteal mRNA for LH receptors to prevent loss of occupied and unoccupied LH receptors and therefore to sustaining luteal function. PMID:20381634

Weems, Y S; Nett, T M; Rispoli, L A; Davis, T L; Johnson, D L; Uchima, T; Raney, A; Lennon, E; Harbert, T; Bowers, G; Tsutahara, N; Randel, R D; Weems, C W

2010-04-08

3

In vivo investigation of luteal function in dogs: Effects of cabergoline, a dopamine agonist, and prolactin on progesterone secretion during mid-pregnancy and diestrus  

Microsoft Academic Search

The role of prolactin on luteal function in dogs was investigated in vivo. The function of prolactin in mid-luteal phase was compared in pregnant and nonpregnant dogs. A dopamine agonist, cabergoline, known for its prolactin secretion inhibitory effects, was injected subcutaneously at a dose of 5 ?g\\/kg body weight in five pregnant and five nonpregnant Beagle bitches. Mean plasma prolactin

K. Onclin; J. P. Verstegen

1997-01-01

4

In vivo investigation of luteal function in dogs: effects of cabergoline, a dopamine agonist, and prolactin on progesterone secretion during mid-pregnancy and -diestrus.  

PubMed

The role of prolactin on luteal function in dogs was investigated in vivo. The function of prolactin in mid-luteal phase was compared in pregnant and nonpregnant dogs. A dopamine agonist, cabergoline, known for its prolactin secretion inhibitory effects, was injected subcutaneously at a dose of 5 micrograms/kg body weight in five pregnant and five nonpregnant Beagle bitches. Mean plasma prolactin and progesterone were dramatically suppressed for 4 to 5 days after injection in both groups when compared with control pregnant and non-pregnant animals, whereas no effect on luteinizing hormone (LH) secretion was observed. The decline in plasma progesterone occurred after that in prolactin, suggesting plasma progesterone was impaired by inhibition of prolactin secretion. These results confirm the luteotropic importance of prolactin in pregnant bitches, and also demonstrate its importance in luteal phase of the nonpregnant dog. Second, to demonstrate that the effects of cabergoline were mediated by prolactin inhibition and not by a direct action on the corpus luteum, concomitant administration on Day 30 of cabergoline and prolactin (375 micrograms i.v. twice daily on Days 30 and 31) or cabergoline and LH (750 micrograms i.v. twice daily on Days 30 and 31) was affected in two groups of five pregnant animals each. Results showed that only prolactin was able to reverse the negative effects of cabergoline on circulating progesterone. This confirms the indirect mode of action of the dopamine agonist, cabergoline on corpus luteum function. Third, further investigation on the precise luteotropic role of prolactin was made by IV injection of 375 micrograms pure canine prolactin twice daily in five pregnant bitches on Days 30 and 31, and in five pregnant bitches on Days 40 and 41. No direct stimulatory effect of prolactin on plasma progesterone secretion occurred. Nor was there a noticeable effect on plasma LH secretion. These results suggest that prolactin is unable to directly stimulate progesterone secretion by the corpus luteum of pregnancy. The results of this study suggest that prolactin is an essential luteotropin in the dog from mid-luteal phase in both pregnant and nonpregnant animals. However, it appears to act by sustaining corpus luteum lifespan and function rather than by direct stimulatory effects on progesterone secretion. PMID:8985667

Onclin, K; Verstegen, J P

1997-01-01

5

Effects of bromodichloromethane on ex vivo and in vitro luteal function and bromodichloromethane tissue dosimetry in the pregnant F344 rat  

Microsoft Academic Search

Bromodichloromethane (BDCM), a drinking water disinfection by-product, causes pregnancy loss, i.e. full-litter resorption, in F344 rats when treated during the luteinizing hormone (LH)-dependent period. This effect is associated with reduced maternal serum progesterone (P) and LH levels, suggesting that BDCM disrupts secretion of LH. To test the hypothesis that BDCM also affects luteal responsiveness to LH, we used ex vivo

S. R. Bielmeier; A. S. Murr; D. S. Best; R. A. Harrison; R. A. Pegram; J. M. Goldman; M. G. Narotsky

2007-01-01

6

Gonadotropins and Cytokines Affect Luteal Function through Control of Apoptosis in Human Luteinized Granulosa Cells  

Microsoft Academic Search

The luteal phase in the normal human menstrual cycle is known to be about 14 days. The physiological mechanisms that regulate the corpus luteum remain to be clarified, although apoptosis is reported to be involved. This study was undertaken to investigate the regu- lation of luteal function by gonadotropins, cytokines, and PGs, con- centrating attention on the incidence of apoptosis

HIROKAZU MATSUBARA; KATSUO IKUTA; YASUHIKO OZAKI; YUKA SUZUKI; NORITAKA SUZUKI; TAKESHI SATO; KAORU SUZUMORI

7

Escherichia coli lipopolysaccharide administration transiently suppresses luteal structure and function in diestrous cows.  

PubMed

The objective was to characterize the effects of Escherichia coli lipopolysaccharide (LPS) endotoxin (given i.v.) on luteal structure and function. Seven nonlactating German Holstein cows, 5.1 ± 0.8 years old (mean ± s.e.m.), were given 10? ml saline on day 10 (ovulation=day 1) of a control estrous cycle. On day 10 of a subsequent cycle, they were given 0.5 ?g/kg LPS. Luteal size decreased (from 5.2 to 3.8 cm², P?0.05) within 24 h after LPS treatment and remained smaller throughout the remainder of the cycle. Luteal blood flow decreased by 34% (P?0.05) within 3 h after LPS and remained lower for 72 h. Plasma progesterone (P?) concentrations increased (P?0.05) within the first 3 h after LPS but subsequently declined. Following LPS treatment, plasma prostaglandin (PG) F metabolites concentrations were approximately tenfold higher in LPS-treated compared with control cows (9.2 vs 0.8 ng/ml, P?0.05) within 30 min, whereas plasma PGE concentrations were nearly double (P?0.05) at 1 h after LPS. At 12 h after treatment, levels of mRNA encoding Caspase-3 in biopsies of the corpus luteum (CL) were increased (P?0.05), whereas those encoding StAR were decreased (P?0.05) in cattle given LPS vs saline. The CASP3 protein was localized in the cytoplasm and/or nuclei of luteal cells, whereas StAR was detected in the cytosol of luteal cells. In the estrous cycle following treatment with either saline or LPS, there were no significant differences between groups on luteal size, plasma P? concentrations, or gene expression. In conclusion, LPS treatment of diestrus cows transiently suppressed both the structure and function of the CL. PMID:22829687

Herzog, K; Strüve, K; Kastelic, J P; Piechotta, M; Ulbrich, S E; Pfarrer, C; Shirasuna, K; Shimizu, T; Miyamoto, A; Bollwein, H

2012-07-24

8

Endocrine and molecular control of luteal and placental function in dogs: a review.  

PubMed

In the domestic dog (Canis familiaris), the corpus luteum (CL) is the only source of progesterone (P4) in non-pregnant and pregnant animals. The progesterone secretion profiles are almost identical in both conditions until the last third of the luteal phase when the gradual P4 decline turns into a steep drop in pregnant bitches, indicating the onset of parturition. Consequently, the length of the CL-phase in non-pregnant dogs exceeds the luteal lifespan in pregnant animals. The canine CL-function is regulated by many species-specific regulatory mechanisms, the most intriguing of which is the reported independence of gonadotropic support during the first third of dioestrus. Recently, PGE2 has been proposed as one of the most important luteotropic factors acting locally during this time, but afterwards prolactin (PRL) appears to be the main luteotropic factor. Luteal regression/luteolysis occurs, however, in spite of an increased gonadotropic support. Lately, by demonstrating the expression of PRL-receptor (PRLr), a new insight into possible regulatory mechanisms has indicated that the supply of P4 could be controlled upstream of the steroidogenic machinery at the level of PRLr expression and/or function, subsequently leading to the functional suppression of the steroidogenic machinery. An endogenous source of a luteolytic agent is apparently lacking, implicating the luteal regression in non-pregnant bitches as a passive, degenerative process even if the PGF2?-receptor is constitutively expressed in canine CL. This is in contrast to pregnant dogs in which prepartum luteolysis seems to be an active process of CL destruction by PGF2? of utero/placental origin targeting the luteal PGF2?-receptor. PMID:23279458

Kowalewski, M P

2012-12-01

9

Endometritis impairs luteal development, function, and nitric oxide and ascorbic acid concentrations in buffalo (Bubalus bubalis).  

PubMed

A vast majority of the world buffalo resource is concentrated in tropical and subtropical countries. Apart from heat stress and poor nutritional availability, endometritis is one of the most commonly encountered reproductive problems limiting fertility and consequently productive potential of the species. As demonstrated recently, endometritis impairs growth and follicular fluid composition of the largest follicle in buffalo. In the present study, the effect of endometritis on luteal development, function, nitric oxide (NO), and ascorbic acid was investigated. Reproductive tracts were collected from 90 cyclic buffaloes at an abattoir and grouped into endometritic (n?=?36) or non-endometritic (n?=?54) buffaloes based on physical examination of uterine mucus, white side test, and uterine cytology. Samples with pus-containing mucus, positive reaction on white side test, and/or >5 % neutrophils were considered to be positive for endometritis. Corpora lutea were enucleated, weighed, classified into stages I to IV, and assayed for progesterone (P(4)), NO, and ascorbic acid concentrations. Endometritic buffaloes had lesser (P?luteal weight and P(4), NO, and ascorbic acid concentrations than non-endometritic buffaloes. The findings indicated that endometritis impairs corpus luteum development and function in buffalo. Reduced luteal NO and ascorbic acid concentrations during endometritis are novel findings. PMID:23070685

Pande, Megha; Das, Goutam Kumar; Khan, Firdous Ahmad; Sarkar, Mihir; Pathak, Mohan Chandra; Prasad, Jai Kishan; Kumar, Harendra

2012-10-16

10

Inhibition of Delta-Like Ligand 4 Induces Luteal Hypervascularization Followed by Functional and Structural Luteolysis in the Primate Ovary  

PubMed Central

Using specific inhibitors established that angiogenesis in the ovarian follicle and corpus luteum is driven by vascular endothelial growth factor. Recently, it has been demonstrated that the Notch ligand, delta-like ligand 4 (Dll4) negatively regulates vascular endothelial growth factor-mediated vessel sprouting and branching. To investigate the role of Dll4 in regulation of the ovarian vasculature, we administered a neutralizing antibody to Dll4 to marmosets at the periovulatory period. The vasculature was examined on luteal d 3 or d 10: angiogenesis was determined by incorporation of bromodeoxyuridine, staining for CD31 and cell death by staining for activated caspase-3. Ovulatory progesterone rises were monitored to determine effects of treatment on luteal function and time to recover normal cycles in a separate group of animals. Additionally, animals were treated in the follicular or midluteal phase to determine effects of Dll4 inhibition on follicular development and luteal function. Controls were treated with human IgG (Fc). Corpora lutea from marmosets treated during the periovulatory period exhibited increased angiogenesis and increased vascular density on luteal d 3, but plasma progesterone was significantly suppressed. By luteal d 10, corpora lutea in treated ovaries were significantly reduced in size, with involution of luteal cells, increased cell death, and suppressed plasma progesterone concentrations. In contrast, initiation of anti-Dll4 treatment during the midluteal phase produced only a slight suppression of progesterone for the remainder of the cycle. Moreover, Dll4 inhibition had no appreciable effect on follicular development. These results show that Dll4 has a specific and critical role in the development of the normal luteal vasculature.

Hastings, Julie M.; Allan, Deborah; Morris, Keith D.; Rudge, John S.; Wiegand, Stanley J.

2012-01-01

11

Failure to maintain luteal function: a possible cause of early embryonic loss in a cow.  

PubMed Central

The effect of early pregnancy failure on the release of prostaglandin F2 alpha (PGF2 alpha) in response to oxytocin (Ot) was examined in an abnormal breeder (AB) heifer that was not able to maintain a pregnancy beyond 21 days. This animal was used in three experiments: 1) She received one intravenous injection of 100 IU Ot 17 days after the onset of oestrus (Day 0). Frequent blood samples were taken for the measurement of 15-keto-13,14-dihydro-PGF2 alpha (PGFM) by radioimmunoassay. Daily samples for progesterone (P4) determinations were taken to monitor luteal function. This was then repeated using the same animal at either day 17 or 18 or 19 (day 17-19) of pregnancy. 2) Embryos from superovulated normal breeder (NB) donors were transferred at day 7 to the AB heifer as well as to NB control animals. 3) Seven day old embryos from the superovulated AB heifer were transferred to NB recipient animals. At day 17-19 of pregnancy all the recipient heifers (experiments 2 and 3) were subjected to the same protocol as in experiment 1. The results showed that the ability of Ot to stimulate PGF2 alpha release was reduced in the NB recipients bearing viable embryos when compared to cyclic animals. However, for the AB heifer, Ot stimulated PGF2 alpha release to the same extent whether the animal was cyclic or pregnant. Furthermore, the AB animal did not have the extended luteal function associated with removal of viable embryos on day 17-19. The data suggest that the embryonic loss might have been caused by failure of the embryos to prevent the luteolytic release of PGF2 alpha.

Lafrance, M; Goff, A K; Guay, P; Harvey, D

1989-01-01

12

Effects of beta-carotene and vitamin A on bovine luteal function  

SciTech Connect

Initially, the direct effects of B-carotene and vitamin A on progesterone (P4) production were studied by exposing dispersed luteal cells to these compounds in vitro. There were no positive relationships between P4 and B-carotene or vitamin A. However, a negative, and perhaps toxic, effect of a large dose of B-carotene on P4 reproduction was noted. A positive relationship between plasma B-carotene and percent change of P4 in the medium of dispersed luteal cells was demonstrated when these plasma metabolites were measured in slaughterhouse cows from which CL were obtained for incubation. This relationship was only present during the winter when plasma levels of B-carotene and vitamin A were considerably lower. Preliminary investigations into the mechanism of action of B-carotene and/or vitamin A were initiated. Luteal tissue ribonucleic acid (RNA), deoxyribonucleic acid (DNA), the RNA to DNA ratio and total protein concentration were measured to study the influence of plasma levels of B-carotene and vitamin A on the protein synthetic capacity of luteal tissue. There were no relationships detected, however, RNA concentration and the RNA to DNA ratio of luteal tissue were greater during the summer. The percent binding of radiolabeled vitamin A was greater in the nuclear than in the cytoplasmic component of the luteal cell.

Graves-Hoagland, R.L.

1987-01-01

13

Prostaglandin Biosynthesis, Transport, and Signaling in Corpus Luteum: A Basis for Autoregulation of Luteal Function  

Microsoft Academic Search

The corpus luteum (CL) is a transient ovarian endocrine gland formed from the ovulated follicle. Progesterone is the primary secretory product of CL and is essential for establishment of pregnancy in mammals. In the cyclic female, the life span of CL is characterized by luteal development, maintenance, and regression regulated by complex interactions between lu- teotrophic and luteolytic mediators. It

J. A. Arosh; S. K. BANU; P. CHAPDELAINE; E. MADORE; J. SIROIS; M. A. FORTIER

2004-01-01

14

Luteal function and follicular growth following follicular aspiration during the peri-luteolysis period in Bos indicus and crossbred cattle.  

PubMed

Follicular estradiol triggers luteolysis in cattle. Therefore, the control of follicle growth and steroidogenesis is expected to modulate luteal function and might be used as an anti-luteolytic strategy to improve embryo survival. Objectives were to evaluate follicular dynamics, plasma concentrations of estradiol and luteal lifespan in Bos indicus and crossbred cows subjected to sequential follicular aspirations. From D13 to D25 of a synchronized cycle (ovulation = D1), Nelore or crossbred, non-pregnant and non-lactating cows were submitted to daily ultrasound-guided aspiration of follicles >6 mm (n = 10) or to sham aspirations (n = 8). Diameter of the largest follicle on the day of luteolysis (7.4 ± 1.0 vs 9.7 ± 1.0 mm; mean ± SEM), number of days in which follicles >6?mm were present (2.3?±?0.4 vs 4.6?±?0.5 days) and daily mean diameter of the largest follicle between D15 and D19 (6.4 ±?0.2 vs 8.5?±?0.3?mm) were smaller (p?luteal lifespan was similar (p?>?0.10) between the groups (19.6 ± 0.4 days), whereas the oestrous cycle was longer (p?

Bisinotto, R S; Ibiapina, B T; Pontes, E O; Bertan, C M; Satrapa, R; Barros, C M; Binelli, M

2011-08-24

15

Luteal and placental function in the bitch: spatio-temporal changes in prolactin receptor (PRLr) expression at dioestrus, pregnancy and normal and induced parturition  

PubMed Central

Background Endocrine mechanisms governing canine reproductive function remain still obscure. Progesterone (P4) of luteal origin is required for maintenance of pregnancy. Corpora lutea (CL) are gonadotrop-independent during the first third of dioestrus; afterwards prolactin (PRL) is the primary luteotropic factor. Interestingly, the increasing PRL levels are accompanied by decreasing P4 concentrations, thus luteal regression/luteolysis occurs in spite of an increased availability of gonadotropic support. PRL acts through its receptor (PRLr), the expression of which has not yet been thoroughly investigated at the molecular and cellular level in the dog. Methods The expression of PRLr was assessed in CL of non-pregnant dogs during the course of dioestrus (days 5, 15, 25, 35, 45, 65 post ovulation; p.o.) as well as in CL, the utero/placental compartments (Ut/Pl) and interplacental free polar zones (interplacental sites) from pregnant dogs during the pre-implantation, post-implantation and mid-gestation period of pregnancy and during the normal and antigestagen-induced luteolysis. Expression of PRLr was tested by Real Time PCR, immunohistochemistry and in situ hybridization. Results In non-pregnant CL the PRLr expression was significantly upregulated at day 15 p.o. and decreased significantly afterwards, towards the end of dioestrus. CL of pregnancy showed elevated PRLr expression until mid gestation while prepartal downregulation was observed. Interestingly, placental but not interplacental expression of PRLr was strongly time-related; a significant upregulation was observed towards mid-gestation. Within the CL PRLr was localized to the luteal cells; in the Ut/Pl it was localized to the fetal trophoblast and epithelial cells of glandular chambers. Moreover, in mid-pregnant animals treated with an antigestagen, both the luteal and placental, but not the uterine PRLr were significantly downregulated. Conclusions The data presented suggest that the luteal provision of P4 in both pregnant and non-pregnant dogs may be regulated at the PRLr level. Furthermore, a role of PRL not only in maintaining the canine CL function but also in regulating the placental function is strongly suggested. A possible functional interrelationship between luteal P4 and placental and luteal PRLr expression also with respect to the prepartal luteolysis is implied.

2011-01-01

16

The small luteal cell of the sheep.  

PubMed Central

Corpora lutea of sheep were examined by electron microscopy at day 10 of the oestrous cycle and at days 15, 25, 50, 100, 125 and 140 of pregnancy. Small luteal cells were present in all corpora lutea, and were two to three times as numerous as large luteal cells. The former were irregular in shape, with tapering cytoplasmic processes. Their major cytoplasmic organelles were a predominantly smooth endoplasmic reticulum, mitochondria with tubular and lamellar cristae, and one or more Golgi complexes. The enzyme delta 5-3 beta-hydroxysteroid dehydrogenase was present in their cytoplasm. Small luteal cells were often interposed between large luteal cells and capillaries, and formed close, complex surface relationships with large luteal cells. Small and large luteal cells differed in many ways, including the restriction of numerous approximately 0.2 micron cytoplasmic granules to the large cells, and no cells of intermediate structure were observed. These features of small luteal cells suggest a steroid hormone synthetic function, and direct interaction with large luteal cells. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 Fig. 7 Fig. 8 Fig. 9 Fig. 10 Fig. 11

O'Shea, J D; Cran, D G; Hay, M F

1979-01-01

17

Equine luteal function regulation may depend on the interaction between cytokines and vascular endothelial growth factor: an in vitro study.  

PubMed

We hypothesized that cytokines influence luteal angiogenesis in mares, while angiogenic factors themselves can also regulate luteal secretory capacity. Therefore, the purpose of this study was to evaluate the role of cytokines--tumor necrosis factor alpha (TNF), interferon gamma (IFNG) and Fas ligand (FASL)--on in vitro modulation of angiogenic activity and mRNA level of vascular endothelial growth factor A (VEGF), its receptor VEGFR2, thrombospondin 1 (TSP1), and its receptor CD36 in equine corpus luteum (CL) throughout the luteal phase. After treatment, VEGF protein expression was determined in midluteal phase (mid) CL cells. The role of VEGF on regulation of luteal secretory capacity was assessed by progesterone (P(4)) and prostaglandin E(2) (PGE(2)) production and by mRNA levels for steroidogenic enzymes 3-beta-hydroxysteroid dehydrogenase (3betaHSD) and PGE synthase (PGES). In early CL cells, TNF increased angiogenic activity (bovine aortic endothelial cell viability) and VEGF and VEGFR2 mRNA levels and decreased CD36 (real-time PCR relative quantification). In mid-CL cells, TNF increased VEGF mRNA and protein expression (Western blot analysis) and reduced CD36 mRNA levels, while FASL and TNF+IFNG+FASL decreased VEGF protein expression. In late CL cells, TNF and TNF+IFNG+FASL reduced VEGFR2 mRNA, but TNF+IFNG+FASL increased TSP1 and CD36 mRNA. VEGF treatment increased mRNA levels of 3betaHSD and PGES and secretion of P(4) and PGE(2). In conclusion, these findings suggest a novel auto/paracrine action of cytokines, specifically TNF, on the up-regulation of VEGF for angiogenesis stimulation in equine early CL, while at luteolysis, cytokines down-regulated angiogenesis. Additionally, VEGF stimulated P(4) and PGE(2) production, which may be crucial for CL establishment. PMID:22492973

Galvão, António; Henriques, Sofia; Pestka, Daria; Lukasik, Karolina; Skarzynski, Dariusz; Mateus, Luisa Maria; Ferreira-Dias, Graça Maria Leitao

2012-06-22

18

Systemic and Intraluteal Infusion of Inhibin A or Activin A in Rhesus Monkeys during the Luteal Phase of the Menstrual Cycle1  

Microsoft Academic Search

The endocrine or local actions of inhibin-related peptides synthesized by the primate corpus luteum (CL) remain undefi ned. This in vivo study was designed to determine whether exogenous inhibin or activin modulates pituitary gonadotropin secretion and the functional life span of the CL during the luteal phase of the menstrual cycle. Beginning at midluteal phase of the cycle, either vehicle

RICHARD L. STOUFFER; KRISTINE D. DAHL; DAVID L. HESS; TERESA K. WOODRUFF; JENNIE P. MATHER; THEODORE A. MOLSKNESS

19

Effect of short-term treatment with bovine somatotropin at estrus on conception rate and luteal function of repeat-breeding dairy cows.  

PubMed

We studied the effect of recombinant bovine somatotropin (rbST) at the time of estrus on progesterone concentrations and conception rates of repeat-breeding Holstein cows. We used repeat-breeding cows of varied parity (n = 510). All the animals were clinically healthy and had had at least three unsuccessful services before entering the study. After detection of estrus, the cows were randomly assigned to either a treated (n = 201) or a control (n = 309) group. The animals in the treated group were given rbST (500 mg s.c.) at the time of estrus and again 10 d later. Artificial insemination was performed 12 h after the first detection of estrus. In order to evaluate the effect of rbST on luteal function, blood samples were taken from 10 cows in each group every 3 d for 18 d, starting on the day of insemination (Day 0) to determine progesterone concentrations. Conception rates were significantly higher (P < 0.05) in the cows treated with rbST (29.3%) than in the control cows (16.9%). The effects of rbST were maximal in cows with 8 or more previous unsuccessful services and in cows with 2 to 4 calvings. Progesterone concentrations tended to be higher in nonpregnant cows that were treated with rbST than in those that were not treated. The difference between groups was significant (p < 0.05) on Day 18 after insemination. In pregnant cows there were no significant differences in progesterone concentrations between treated and nontreated animals at any time. Treatment with rbST at estrus improved the conception rate of repeat-breeding Holstein cows. This effect was associated with an increase in circulating progesterone concentrations on Day 18. PMID:11414488

Morales-Roura, J S; Zarco, L; Hernández-Cerón, J; Rodríguez, G

2001-06-01

20

Luteal insufficiency in first trimester  

PubMed Central

Luteal phase insufficiency is one of the reasons for implantation failure and has been responsible for miscarriages and unsuccessful assisted reproduction. Luteal phase defect is seen in women with polycystic ovaries, thyroid and prolactin disorder. Low progesterone environment is created iatrogenically due to interventions in assisted reproduction. Use of gonadotrophin-releasing hormone analogs to prevent the LH surge and aspiration of granulosa cells during the oocyte retrieval may impair the ability of corpus luteum to produce progesterone. Treatment of the underlying disorder and use of progestational agents like progesterone/human chorionic gonadotrophin have been found to be effective in women with a history of recurrent miscarriage. There has been no proved beneficial effect of using additional agents like ascorbic acid, estrogen, prednisolone along with progesterone. Despite their widespread use, further studies are required to establish the optimal treatment. Literature review and analysis of published studies on luteal phase support.

Shah, Duru; Nagarajan, Nagadeepti

2013-01-01

21

Characterization of bovine immortalized luteal endothelial cells: action of cytokines on production and content of arachidonic acid metabolites  

Microsoft Academic Search

Background  The interactions between luteal, vascular endothelial, immune cells and its products: steroids, peptide hormones, prostaglandins\\u000a (PGs), growth factors and cytokines play a pivotal role in the regulation of corpus luteum (CL) function. Luteal endothelial\\u000a cells undergo many dynamic morphological changes and their action is regulated by cytokines. The aims are: (1) to establish\\u000a in vitro model for bovine luteal endothelial

Anna J Korzekwa; Gabriel Bodek; Joanna Bukowska; Agnieszka Blitek; Dariusz J Skarzynski

2011-01-01

22

Luteal phase support for assisted reproduction cycles  

Microsoft Academic Search

BACKGROUND: Progesterone prepares the endometrium for pregnancy by stimulating proliferation in response to human chorionic gonadotropin (hCG), which is produced by the corpus luteum. This occurs in the luteal phase of the menstrual cycle. In assisted reproduction techniques (ART) the progesterone or hCG levels, or both, are low and the natural process is insufficient, so the luteal phase is supported

M. Van der Linden; K. Buckingham; C. Farquhar; J. A. M. Kremer; M. Metwally

2011-01-01

23

Changes in luteal cells distribution, apoptotic rate, lipid peroxidation levels and antioxidant enzyme activities in buffalo (Bubalus bubalis) corpus luteum.  

PubMed

Buffalo (Bubalus bubalis) is known for its weak/silent estrous behaviour, lower conception rate and longer inter-calving interval as compared to cattle. Understanding the kinetics and functional properties of luteal cells may be helpful to improve reproductive efficiency in the buffalo. Hence the present study was designed to assess the size and distribution of steroidogenic luteal cells along with biochemical properties during different phases of corpus luteum (CL) in the buffalo. The ovaries collected from the local abattoir were classified into three phases, early, mid and late, based on the morphological appearance of the CL as well as the follicles in the ovary. The proportion (%) of the luteal cells (>10microm diameter) increased (P<0.01) from early (30.7+/-1.3) to mid (36.30+/-1.6), and then decreased (P<0.01) in late luteal (31.46+/-1.8) phases. Percentage of small luteal cells (10-20microm diameter) was higher (P<0.05) in early (58.47+/-0.61) and mid (61.29+/-0.67) than late luteal (37.18+/-1.50) phases of CL. However, the percentage of large luteal cells (20-50microm diameter) was higher (P<0.05) only in late (62.82+/-1.50) than early (41.53+/-0.61) and mid (38.71+/-0.67) phases of CL. The average size (microm) of the large luteal cells increased (P<0.05) from early (25.46+/-0.62) to mid (27.15+/-0.5) and late (28.86+/-0.47) luteal phases. The percentage of luteal cells expressing in situ DNA fragmentation was significantly (P<0.05) higher in the late luteal (41.17+/-5.8) than mid-luteal (21.15+/-4.9) phase of the CL. In the early stage, half of the steroidogenic luteal cells had significantly (P<0.05) less 3beta-HSD activity than the other two phases. In the mid stage, the steroidogenic luteal cells had significantly higher (P<0.05) intense 3beta-HSD activity than the other two phases. Further in the late phase, a significant (P<0.05) reduction in intense 3beta-HSD activity was observed in the large luteal cells. The lipid peroxidation (micromol/g of CL) levels were significantly (P<0.05) higher in late luteal (3.46+/-0.2) than the mid-luteal (1.43+/-0.16) phases. The superoxide dismutase and catalase enzyme levels (U/mg of protein) were also significantly (P<0.05) higher in late luteal (0.9+/-0.015 and 3.37+/-0.45, respectively) than the mid-luteal (0.1+/-0.01 and 2.34+/-0.3, respectively) phases. In contrast, the GPx activity (U/mg of protein) decreased significantly (P<0.05) from mid-luteal (1.85+/-0.4) to late luteal (1.22+/-0.2) phases. The present study suggests that (i) the decrease in progesterone levels in late CL may be associated with loss of 3beta-HSD activity in large luteal cells and (ii) demise of the buffalo CL may be mediated by apoptosis despite the high levels of luteal antioxidant enzymes. PMID:20378285

Selvaraju, S; Raghavendra, B S; Subramani, T Siva; Priyadharsini, R; Reddy, I J; Ravindra, J P

2010-02-25

24

Is there a difference in the function of granulosa-luteal cells in patients undergoing in-vitro fertilization either with gonadotrophin-releasing hormone agonist or gonadotrophin-releasing hormone antagonist?  

PubMed

Gonadotrophin-releasing hormone (GnRH) regulates gonadotrophin release. It has been shown that GnRH may have a direct effect on the ovary, as the addition of GnRH to granulosa cell cultures inhibits the production of progesterone and oestradiol. Specific GnRH receptors have been found to be present in rat and human granulosa cells. Desensitization of the pituitary by GnRH agonist has become common in in-vitro fertilization (IVF) treatment, usually by a long protocol of 2-3 weeks. With the introduction of GnRH antagonists, which produce an immediate blockage of the GnRH receptors, a much shorter exposure is needed of 3-6 days. The aim of this study was to evaluate the effect of a GnRH agonist (buserelin) and a GnRH antagonist (cetrorelix) on the function of granulosa cells cultured in vitro from IVF patients. Women were treated by IVF randomized either to have buserelin nasal spray from the luteal phase in the previous cycle or cetrorelix from day 6 of the cycle. Both groups had ovarian stimulation with human menopausal gonadotrophin (HMG) 150 IU daily, i.e. HCG was administered when the follicles were larger than 17 mm, and aspirated 36 h later. Granulosa cells, separated and washed from large follicles containing ova, were pooled. After 48 h of pre-incubation, the granulosa cells were cultured for 4 days in medium with either added testosterone or cAMP with or without HCG, with change of medium after 2 days. The progesterone and oestradiol concentrations in the culture medium were measured by immunological assay, and cellular protein was measured by microprotein assay. The results showed that granulosa cells from women treated with GnRH antagonist (cetrorelix) responded earlier to the in-vitro hormone stimulation in terms of progesterone accumulation than women treated with the GnRH agonist (buserelin). This may have been due to difference in time of exposure to the analogue. The results may indicate that the luteal function is less impaired in GnRH antagonist treatment than in GnRH agonist treatment. PMID:10221213

Lin, Y; Kahn, J A; Hillensjö, T

1999-04-01

25

Luteal function, largest follicle, and fertility in postpartum dairy cows treated with 14dCIDR-PGF2? versus 2xPGF2?-Ovsynch for timed AI.  

PubMed

A method for timed artificial insemination (AI) that is used for beef cows, beef heifers, and dairy heifers employs progesterone-releasing inserts, such as the controlled internal drug release (CIDR; Zoetis, New York, NY, USA) that are left in place for 14 days. The 14-day CIDR treatment is a method of presynchronization that ensures that cattle are in the late luteal phase of the estrous cycle when PGF2? is administered before timed AI. The objective of this study was to test the effectiveness of the 14dCIDR-PGF2? program in postpartum dairy cows by comparing it with the traditional "Presynch-Ovsynch" (2xPGF2?-Ovsynch) program. The 14dCIDR-PGF2? cows (n = 132) were treated with a CIDR insert on Day 0 for 14 days. At 19 days after CIDR removal (Day 33), the cows were treated with a luteolytic dose of PGF2?, 56 hours later were treated with an ovulatory dose of GnRH (Day 35), and 16 hours later were inseminated. The 2xPGF2?-Ovsynch cows were treated with a luteolytic dose of PGF2? on Day 0 and again on Day 14. At 12 days after the second PGF2? treatment (Day 26), the cows were treated with GnRH. At 7 days after GnRH, the cows were treated with PGF2? (Day 33), then 56 hours later treated with GnRH (Day 35), and then 16 hours later were inseminated. There was no effect of treatment or treatment by parity interaction on pregnancies per AI (P/AI) when pregnancy diagnosis was performed on Day 32 (115/263; 43.7%) or Days 60 to 90 (99/263; 37.6%) after insemination. There was an effect of parity (P < 0.05) on P/AI because primiparous cows had lesser P/AI (35/98; 35.7%) than multiparous cows (80/165; 48.5%) on Day 32. Cows observed in estrus after the presynchronization step (within 5 days after CIDR removal or within 5 days after the second PGF2? treatment) had greater P/AI than those not observed in estrus (55/103; 53.4% vs. 60/160; 37.5%; observed vs. not observed; P < 0.01; d 32 pregnancy diagnosis). When progesterone data were examined in a subset of cows (n = 208), 55.3% of cows had a "prototypical" response to treatment (i.e., the cow had an estrous cycle that was synchronized by the presynchronization treatment and then the cow responded appropriately to the subsequent PGF2? and GnRH treatments before timed AI). Collectively, cows with a prototypical response to either treatment had 52.2% P/AI that was greater (P < 0.001) than the P/AI for cows that had a nonprototypical response (19%) (P/AI determined at 60-90 days of pregnancy). In conclusion, we did not detect a difference in P/AI when postpartum dairy cows were treated with 14dCIDR-PGF2? or 2xPGF2?-Ovsynch before timed AI. The primary limitation to the success of either program was the failure of the cow to respond appropriately to the sequence of treatments. PMID:23998742

Escalante, Rebecca C; Poock, Scott E; Lucy, Matthew C

2013-08-30

26

An update of luteal phase support in stimulated IVF cycles  

Microsoft Academic Search

Stimulated IVF cycles are associated with luteal phase defect. In order to overcome this, different doses, durations and types of luteal phase support (LPS) have been evaluated. There is still no agreement regarding the optimal supplementation scheme. The aim of this paper is to assess the past and the current clinical practices of luteal supplementation in IVF. The databases of

H. M. Fatemi; B. Popovic-Todorovic; E. Papanikolaou; P. Donoso; P. Devroey

2007-01-01

27

Liver X Receptor Modulation of Gene Expression Leading to Proluteolytic Effects in Primate Luteal Cells1  

PubMed Central

ABSTRACT The expressions of genes involved in cholesterol efflux increase, whereas those involved in extracellular cholesterol uptake decrease, during spontaneous functional regression of the primate corpus luteum (CL). This may result from liver x receptor (LXR) alpha (official symbol NR1H3) and/or beta (official symbol NR1H2) control of luteal gene transcription, because these nuclear receptor superfamily members are key regulators of cellular cholesterol homeostasis. Therefore, studies were conducted to assess endogenous LXR ligands in the primate CL through the luteal phase, and to determine the effect of synthetic or natural LXR ligands on cholesterol efflux and uptake in functional primate luteal cells. Using high-performance liquid chromatography tandem mass spectrometry, three LXR ligands were identified and quantified in the rhesus macaque CL, including 22R-hydroxycholesterol (22ROH), 27-hydroxycholesterol (27OH), and desmosterol. Levels of 22ROH paralleled serum progesterone concentrations, whereas mean levels of 27OH tended to be higher following the loss of progesterone synthesis. Desmosterol was present throughout the luteal phase. Functional macaque luteal cells treated with the synthetic LXR agonist T0901317 or physiologically relevant concentrations of the endogenous luteal ligands 22ROH, 27OH, and desmosterol had increased expression of various known LXR target genes and greater cholesterol efflux. Additionally, T0901317 reduced low-density lipoprotein receptor protein and extracellular low-density lipoprotein uptake, whereas 27OH decreased low-density lipoprotein receptor protein, most likely via a posttranslational mechanism. Collectively, these data support the hypothesis that LXR activation causes increased cholesterol efflux and decreased extracellular cholesterol uptake. In theory, these effects could deplete the primate CL of cholesterol needed for steroidogenesis, ultimately contributing to functional regression.

Bogan, Randy L.; DeBarber, Andrea E.; Hennebold, Jon D.

2011-01-01

28

Functional and Molecular Characterization of a Muscarinic Receptor Type and Evidence for Expression of Choline-Acetyltransferase and Vesicular Acetylcholine Transporter in Human Granulosa-Luteal Cells  

Microsoft Academic Search

Previously, we provided evidence for the presence of a class of muscarinic receptors on human luteinized granulosa cells (human GC) that is linked to transient increases in intracellular free calcium levels, but not to steroid production. The precise nature of the receptor is not known, and neither its function nor the source of its natural ligand acetylcholine (ACh) is clear.

S. FRITZ; K. J. FOHR; S. BODDIEN; U. BERG; C. BRUCKER; A. MAYERHOFER

2010-01-01

29

EPR Spectroscopy of Function In Vivo  

Microsoft Academic Search

EPR can be used to study free radicals in vivo, environmental and biophysical parameters in cells and tissues, and to report metabolism, physiology, and biochemistry. The authors have attempted to judge which of these types of measurements will be productive for studies in animals and in humans. It is envisioned that a large number of in vivo applications of EPR

Harold M. Swartz; Nadeem Khan

30

Gestating for 22 months: luteal development and pregnancy maintenance in elephants.  

PubMed

The corpus luteum, a temporally established endocrine gland, formed on the ovary from remaining cells of the ovulated follicle, plays a key role in maintaining the early mammalian pregnancy by secreting progesterone. Despite being a monovular species, 2-12 corpora lutea (CLs) were found on the elephant ovaries during their long pregnancy lasting on average 640 days. However, the function and the formation of the additional CLs and their meaning remain unexplained. Here, we show from the example of the elephant, the close relationship between the maternally determined luteal phase length, the formation of multiple luteal structures and their progestagen secretion, the timespan of early embryonic development until implantation and maternal recognition. Through three-dimensional and Colour Flow ultrasonography of the ovaries and the uterus, we conclude that pregnant elephants maintain active CL throughout gestation that appear as main source of progestagens. Two LH peaks during the follicular phase ensure the development of a set of 5.4 ± 2.7 CLs. Accessory CLs (acCLs) form prior to ovulation after the first luteinizing hormone (LH) peak, while the ovulatory CL (ovCL) forms after the second LH peak. After five to six weeks (the normal luteal phase lifespan), all existing CLs begin to regress. However, they resume growing as soon as an embryo becomes ultrasonographically apparent on day 49 ± 2. After this time, all pregnancy CLs grow significantly larger than in a non-conceptive luteal phase and are maintained until after parturition. The long luteal phase is congruent with a slow early embryonic development and luteal rescue only starts 'last minute', with presumed implantation of the embryo. Our findings demonstrate a highly successful reproductive solution, different from currently described mammalian models. PMID:22719030

Lueders, Imke; Niemuller, Cheryl; Rich, Peter; Gray, Charlie; Hermes, Robert; Goeritz, Frank; Hildebrandt, Thomas B

2012-06-20

31

Gestating for 22 months: luteal development and pregnancy maintenance in elephants  

PubMed Central

The corpus luteum, a temporally established endocrine gland, formed on the ovary from remaining cells of the ovulated follicle, plays a key role in maintaining the early mammalian pregnancy by secreting progesterone. Despite being a monovular species, 2–12 corpora lutea (CLs) were found on the elephant ovaries during their long pregnancy lasting on average 640 days. However, the function and the formation of the additional CLs and their meaning remain unexplained. Here, we show from the example of the elephant, the close relationship between the maternally determined luteal phase length, the formation of multiple luteal structures and their progestagen secretion, the timespan of early embryonic development until implantation and maternal recognition. Through three-dimensional and Colour Flow ultrasonography of the ovaries and the uterus, we conclude that pregnant elephants maintain active CL throughout gestation that appear as main source of progestagens. Two LH peaks during the follicular phase ensure the development of a set of 5.4 ± 2.7 CLs. Accessory CLs (acCLs) form prior to ovulation after the first luteinizing hormone (LH) peak, while the ovulatory CL (ovCL) forms after the second LH peak. After five to six weeks (the normal luteal phase lifespan), all existing CLs begin to regress. However, they resume growing as soon as an embryo becomes ultrasonographically apparent on day 49 ± 2. After this time, all pregnancy CLs grow significantly larger than in a non-conceptive luteal phase and are maintained until after parturition. The long luteal phase is congruent with a slow early embryonic development and luteal rescue only starts ‘last minute’, with presumed implantation of the embryo. Our findings demonstrate a highly successful reproductive solution, different from currently described mammalian models.

Lueders, Imke; Niemuller, Cheryl; Rich, Peter; Gray, Charlie; Hermes, Robert; Goeritz, Frank; Hildebrandt, Thomas B.

2012-01-01

32

Effect of oxytocin infusion on luteal blood flow and progesterone secretion in dairy cattle  

PubMed Central

The objective of this study was to investigate the effects of oxytocin infusion on corpus luteum (CL) function during early to mid-diestrus by measuring luteal size (LS) and luteal blood flow (LBF) along with plasma levels of progesterone (P4) and prostaglandin metabolites (13,14-dihydro-15-keto-prostaglandin F2?, PGFM). On day (D) 7 of the estrus cycle (D1 = ovulation), seven cows received 100 IU of oxytocin (OXY) or placebo (PL) following a Latin square design. LS and LBF increased in both groups over time and no differences were observed between the groups. PGFM did not differ either within the groups over time or between the groups at any time point. P4 of the OXY group was higher compared to that of the the PL group 360 min after the infusion (p = 0.01) and tended to be higher at the time points 450 min, 48 h, and 72 h (all p = 0.08). Results from this study support the hypothesis that OXY is not directly involved in the mechanism(s) governing blood flow of the CL and has no remarkable effects either on luteal size or P4 and PGFM plasma levels. Further investigation is needed to elucidate the role of OXY in CL blood flow during early and late luteal phases.

Brozos, Christos N.; Pancarci, Metin S.; Valencia, Javier; Beindorff, Nikola; Kiossis, Evaggelos; Bollwein, Heinrich

2012-01-01

33

Identification of miRNAs associated with the follicular-luteal transition in the ruminant ovary.  

PubMed

Little is known about the involvement of microRNAs (miRNAs) in the follicular-luteal transition. The aim of this study was to identify genome-wide changes in miRNAs associated with follicular differentiation in sheep. miRNA libraries were produced from samples collected at defined stages of the ovine oestrous cycle and representing healthy growing follicles, (diameter, 4.0-5.5 ?mm), pre-ovulatory follicles (6.0-7.0 ?mm), early corpora lutea (day 3 post-oestrus) and late corpora lutea (day 9). A total of 189 miRNAs reported in sheep or other species and an additional 23 novel miRNAs were identified by sequencing these libraries. miR-21, miR-125b, let-7a and let-7b were the most abundant miRNAs overall, accounting for 40% of all miRNAs sequenced. Examination of changes in cloning frequencies across development identified nine different miRNAs whose expression decreased in association with the follicular-luteal transition and eight miRNAs whose expression increased during this transition. Expression profiles were confirmed by northern analyses, and experimentally validated targets were identified using miRTarBase. A majority of the 29 targets identified represented genes known to be actively involved in regulating follicular differentiation in vivo. Finally, luteinisation of follicular cells in vitro resulted in changes in miRNA levels that were consistent with those identified in vivo, and these changes were temporally associated with changes in the levels of putative miRNA targets in granulosa cells. In conclusion, this is the first study to characterise genome-wide miRNA profiles during different stages of follicle and luteal development. Our data identify a subset of miRNAs that are potentially important regulators of the follicular-luteal transition. PMID:22653318

McBride, D; Carré, W; Sontakke, S D; Hogg, C O; Law, A; Donadeu, F X; Clinton, M

2012-05-31

34

Decreased progesterone receptor isoform expression in luteal phase fallopian tube epithelium and high-grade serous carcinoma  

PubMed Central

We previously reported that BRCA1/2-mutated fallopian tube epithelium (FTE) collected during the luteal phase exhibits gene expression profiles more closely resembling that of high-grade serous carcinoma (HGSC) specimens than FTE collected during the follicular phase or from control patients. Since the luteal phase is characterised by high levels of progesterone, we determined whether the expression of progesterone receptor (PR) and PR-responsive genes was altered in FTE obtained from BRCA mutation carriers during the luteal phase of the menstrual cycle. RT-qPCR confirmed a decreased expression of PR mRNA in FTE during the luteal phase relative to follicular phase, in both BRCA1/2 mutation carriers and control patients. Immunohistochemistry using isoform-specific antibodies confirmed a low level of both PR-A and PR-B in HGSC and a lower level of staining in FTE samples obtained during the luteal phase compared with the follicular phase. No significant difference in PR-A or PR-B staining was found based on patient BRCA mutation status. Analysis of our previously reported gene expression profiles based upon known PR-A- and PR-B-specific target genes did not partition samples by BRCA mutation status, indicating that overall FTE PR response is not altered in BRCA mutation carriers. HGSC samples grouped separately from other samples, consistent with the observed loss of PR expression. These findings indicate no overall difference in PR signalling in FTE as a function of BRCA mutation status. Thus, the molecular similarity of BRCA1/2-mutated luteal phase FTE and HGSC likely results from an altered response to luteal phase factors other than progesterone.

Tone, Alicia A; Virtanen, Carl; Shaw, Patricia A; Brown, Theodore J

2011-01-01

35

Swainsonine differentially affects steroidogenesis and viability in caprine luteal cells in vitro.  

PubMed

Plants containing swainsonine (SW) have been reported to impair reproductive function and fertility after long-term ingestion by livestock. However, direct effects of SW on luteal cell steroidogenesis remain unclear. In this study, primary and transfected luteal cells were used to investigate the effects of SW on progesterone secretion and cell viability and the mechanisms involved in these processes. After treatment with various concentrations of SW for 24 or 48 hours, progesterone production and the number of living cells were assessed using radioimmunoassay and trypan blue dye exclusion assay, respectively. Lower concentrations of SW enhanced basal, 22R-hydroxycholesterol- or pregnenolone-stimulated progesterone secretion (P < 0.05), whereas higher concentrations of SW inhibited progesterone secretion (P < 0.05). Lower concentrations of SW promoted expression of P450 side-chain cleavage enzyme and 3?-hydroxysteroid dehydrogenase, two key enzymes involved in luteal cell steroidogenesis, at mRNA and protein levels (P < 0.05), but did not affect expression of steroidogenic acute regulatory protein and cell proliferation. In contrast, higher concentrations of SW inhibited luteal cell proliferation by inducing growth phase 1/quiescent state cell cycle arrest and apoptosis (P < 0.05). Taken together, these results demonstrated that lower concentrations of SW induced progesterone production through upregulation of P450 side-chain cleavage enzyme and 3?-hydroxysteroid dehydrogenase without affecting cell viability, whereas higher concentrations of SW induced cell cycle arrest and apoptosis and impaired steroidogenesis. These findings provided new insights into understanding the effect of SW on luteal cell steroidogenesis. PMID:23639373

Huang, Yong; Li, Wei; Zhao, Xiaomin; Ding, Li; Yu, Gaoshui; Dong, Feng; Du, Qian; Xu, Xingang; Tong, Dewen

2013-04-29

36

EFFECTS OF BROMODICHLOROMETHANE ON EX VIVO AND IN VITRO LUTEAL FUNCTION AND BROMODICHLOROMETHANE TISSUE DOSIMETRY IN THE PREGNANT F344 RAT  

EPA Science Inventory

Bromodichloromethane (BDCM), a drinking water disinfection by-product, causes pregnancy loss, i.e. full-litter resorption, in F344 rats when treated during the luteinizing hormone (LH)-dependent period. This effect is associated with reduced maternal serum progesterone (P) and LH...

37

Genetic analysis of basophil function in vivo  

PubMed Central

Contributions by basophils to allergic and helminth immunity remain incompletely defined. Using sensitive IL-4 reporter alleles, we demonstrate that basophil IL-4 production occurs by a CD4+ T cell-dependent process restricted to affected peripheral tissues. We genetically marked and specifically deleted basophils and demonstrate that basophils do not mediate TH2 priming in vivo. Two-photon imaging confirmed that basophils do not interact with antigen-specific T cells in lymph nodes, but can engage in prolonged serial interactions with T cells in lung tissues. Although targeted deletion of IL-4 and IL-13 in either CD4+ T cells or basophils minimally impacted worm clearance, deletion from both lineages demonstrated a nonredundant role for basophil cytokines in primary helminth immunity.

Sullivan, Brandon M.; Liang, Hong-Erh; Bando, Jennifer K.; Wu, Davina; Cheng, Laurence E.; McKerrow, James K.; Allen, Christopher D. C.; Locksley, Richard M.

2012-01-01

38

Plasma progesterone concentrations in the mid-luteal phase are dependent on luteal size, but independent of luteal blood flow and gene expression in lactating dairy cows.  

PubMed

The objective of the present study was to investigate if plasma progesterone (pP(4)) concentrations are dependent on luteal size, blood flow, or gene expression in luteal tissue. To induce cycles with high and low pP(4) concentrations, respectively, 20 lactating dairy cows received either a single treatment with 25 mg prostaglandin F(2?) (PGF(2?)) on Day 4 Hour 12 (PG1; n=8), or two treatments (25 mg PGF(2?) each) on Day 4 Hours 0 and 12 (PG2; n=12) of the estrous cycle (Day 1, Hour 0=ovulation). In four cows, ovulation occurred between 4 and 6d after the second PGF(2?) treatment; these cows and one lame cow were excluded from the study. In the 15 remaining cows with physiological interovulatory intervals, pP(4), area (LTA) and volume (LTV) of luteal tissue, as well as absolute (LBF) and relative (rLBF) luteal blood flow were determined on Day 9, and relative luteal P(4) (rLP(4)) as well as luteal mRNA expression of important receptors, angiogenic, vasoactive, and steroidogenic factors were quantified on Day 11 (±1) during two successive estrous cycles. Furthermore, rLP(4) was multiplied by LTV to produce a semiquantitative assessment of absolute luteal P(4) (LP(4)). There was no effect (P>0.05) of treatment (one or two PGF(2?) treatments), neither on pP(4) concentrations nor on any other parameter in the present study. Nevertheless, there was a lower LP(4) (P=0.01), LTA (P=0.03), and LTV (P=0.02), as well as tendencies of lower pP(4) (P=0.06) and LBF (P=0.09) at first compared with second diestrus. Plasma P(4) was related with LP(4) (r=0.43, P=0.04), LTA (r=0.65, P=0.0001), and LTV (r=0.43, P=0.02), but not with rLBF (r=-0.18, P=0.34). Furthermore, there was no significant correlation between gene expression of important steroidogenic factors and P(4) concentrations in luteal tissue. Results indicate that plasma P(4) concentrations in the mid-luteal phase were dependent on luteal size, but independent of blood flow and gene expression per luteal tissue unit. PMID:21398055

Lüttgenau, J; Ulbrich, S E; Beindorff, N; Honnens, A; Herzog, K; Bollwein, H

2011-02-12

39

Gelatinases, endonuclease and Vascular Endothelial Growth Factor during development and regression of swine luteal tissue  

PubMed Central

Background The development and regression of corpus luteum (CL) is characterized by an intense angiogenesis and angioregression accompanied by luteal tissue and extracellular matrix (ECM) remodelling. Vascular Endothelial Growth Factor (VEGF) is the main regulator of angiogenesis, promoting endothelial cell mitosis and differentiation. After the formation of neovascular tubes, the remodelling of ECM is essential for the correct development of CL, particularly by the action of specific class of proteolytic enzymes known as matrix metalloproteinases (MMPs). During luteal regression, characterized by an apoptotic process and successively by an intense ECM and luteal degradation, the activation of Ca++/Mg++-dependent endonucleases and MMPs activity are required. The levels of expression and activity of VEGF, MMP-2 and -9, and Ca++/Mg++-dependent endonucleases throughout the oestrous cycle and at pregnancy were analyzed. Results Different patterns of VEGF, MMPs and Ca++/Mg++-dependent endonuclease were observed in swine CL during different luteal phases and at pregnancy. Immediately after ovulation, the highest levels of VEGF mRNA/protein and MMP-9 activity were detected. On days 5–14 after ovulation, VEGF expression and MMP-2 and -9 activities are at basal levels, while Ca++/Mg++-dependent endonuclease levels increased significantly in relation to day 1. Only at luteolysis (day 17), Ca++/Mg++-dependent endonuclease and MMP-2 spontaneous activity increased significantly. At pregnancy, high levels of MMP-9 and VEGF were observed. Conclusion Our findings, obtained from a precisely controlled in vivo model of CL development and regression, allow us to determine relationships among VEGF, MMPs and endonucleases during angiogenesis and angioregression. Thus, CL provides a very interesting model for studying factors involved in vascular remodelling.

Ribeiro, Luciana Andrea; Turba, Maria Elena; Zannoni, Augusta; Bacci, Maria Laura; Forni, Monica

2006-01-01

40

Mitochondrial Metabolic Function Assessed In Vivo and In Vitro  

PubMed Central

Purpose of review Mitochondrial content and function vary across species, tissue types, and lifespan. Alterations in skeletal muscle mitochondrial function have been reported to occur in in aging and in many other pathological conditions. This review focuses on the state of the art in vivo and in vitro methodologies for assessment of muscle mitochondrial function. Recent findings Classic studies of isolated mitochondria have measured function from maximal respiratory capacity. These fundamental methods have recently been substantially improved and novel approaches to asses mitochondrial functions in vitro have been emerged. Non-invasive methods based on magnetic resonance spectroscopy (MRS) and near-infrared spectroscopy (NIRS) permit in vivo assessment of mitochondrial function and are rapidly becoming more accessible to many investigators. Moreover, it is now possible to gather information on regulation of mitochondrial content by measuring the in vivo synthesis rate of individual mitochondrial proteins. Summary High-resolution respirometry has emerged as a powerful tool for in vitro measurements of mitochondrial function in isolated mitochondria and permeabilized fibers. Direct measurements of ATP production are possible by bioluminescence. Mechanistic data provided by these methods is further complimented by in vivo assessment using MRS and NIRS and the translational rate of gene transcripts.

Lanza, Ian R.; Nair, K. Sreekumaran

2011-01-01

41

In Vivo Evidence for and Consequences of Functional Selectivity  

Microsoft Academic Search

Functional selectivity refers to the ability of some ligands to stimulate a subset of the possible consequences of activation\\u000a of a receptor. This chapter addresses two related issues that are critical for consideration of the therapeutic utility of\\u000a functional selectivity: the evidence that functional selectivity is a pharmacologically relevant phenomenon that can be observed\\u000a in vivo, and characterization of the

Kim A. Neve; Marc G. Caron; Jean-Martin Beaulieu

42

Effect of aspirin on the luteal phase of human menstrual cycle.  

PubMed

The effect of aspirin (acetylsalicylic acid) on the luteal phase length and function was studied in ten normal cycling women. They received three grams daily for twenty days starting from the fifth day of the cycle. Urinary pregnanediol-3 alpha-glucuronide (Pg-diol- 3G ) and luteinising hormone (LH) were assayed in daily early morning urine samples together with daily vaginal smear for cytohormonal evaluation. The excretion profile of Pg-diol- 3G and LH of another group of ten normal women were taken as controls. Aspirin caused shortening of both cycle length and luteal phase duration. Available evidence suggests the presence of corpus luteum deficiency in the treated cycles. PMID:6723311

Souka, A R; Medhat, M; Rahman, H A; Osman, M; El Sokkary, H

1984-02-01

43

Bromocriptine therapy of luteal insufficiency accompanied with hyperprolactinemia in the follicular phase.  

PubMed

The therapeutic effectiveness of bromocriptine was studied in 24 patients (40 cycles) with luteal insufficiency accompanied with hyperprolactinemia in the follicular phase. Treatment with bromocriptine was started on day 5 of each menstrual cycle and continued for 7 days per cycle. In the first menstrual cycle, this 7-day treatment lowered the blood prolactin level, and significantly increased blood estradiol and progesterone in 83.3% of the patients. Among the patients whose prolactin levels were not lowered by bromocriptine, only a few showed increases in estradiol or progesterone. In many of the patients whose prolactin levels were excessively lowered to 5 ng/ml or less, progesterone was decreased. These results suggests that bromocriptine produces a favorable effect on hyperprolactinemic luteal insufficiency by secondarily stimulating progesterone secretion as a result of suppressing the follicular growth "inhibiting action of prolactin. Prolactin of an appropriate concentration, however, was considered to be needed for the maintenance of normal function of the corpus luteum. PMID:6875348

Kano, T; Nishikawa, K

1983-07-01

44

Resurrection of DNA function in vivo from an extinct genome.  

PubMed

There is a burgeoning repository of information available from ancient DNA that can be used to understand how genomes have evolved and to determine the genetic features that defined a particular species. To assess the functional consequences of changes to a genome, a variety of methods are needed to examine extinct DNA function. We isolated a transcriptional enhancer element from the genome of an extinct marsupial, the Tasmanian tiger (Thylacinus cynocephalus or thylacine), obtained from 100 year-old ethanol-fixed tissues from museum collections. We then examined the function of the enhancer in vivo. Using a transgenic approach, it was possible to resurrect DNA function in transgenic mice. The results demonstrate that the thylacine Col2A1 enhancer directed chondrocyte-specific expression in this extinct mammalian species in the same way as its orthologue does in mice. While other studies have examined extinct coding DNA function in vitro, this is the first example of the restoration of extinct non-coding DNA and examination of its function in vivo. Our method using transgenesis can be used to explore the function of regulatory and protein-coding sequences obtained from any extinct species in an in vivo model system, providing important insights into gene evolution and diversity. PMID:18493600

Pask, Andrew J; Behringer, Richard R; Renfree, Marilyn B

2008-05-21

45

Resurrection of DNA Function In Vivo from an Extinct Genome  

PubMed Central

There is a burgeoning repository of information available from ancient DNA that can be used to understand how genomes have evolved and to determine the genetic features that defined a particular species. To assess the functional consequences of changes to a genome, a variety of methods are needed to examine extinct DNA function. We isolated a transcriptional enhancer element from the genome of an extinct marsupial, the Tasmanian tiger (Thylacinus cynocephalus or thylacine), obtained from 100 year-old ethanol-fixed tissues from museum collections. We then examined the function of the enhancer in vivo. Using a transgenic approach, it was possible to resurrect DNA function in transgenic mice. The results demonstrate that the thylacine Col2A1 enhancer directed chondrocyte-specific expression in this extinct mammalian species in the same way as its orthologue does in mice. While other studies have examined extinct coding DNA function in vitro, this is the first example of the restoration of extinct non-coding DNA and examination of its function in vivo. Our method using transgenesis can be used to explore the function of regulatory and protein-coding sequences obtained from any extinct species in an in vivo model system, providing important insights into gene evolution and diversity.

Pask, Andrew J.; Behringer, Richard R.; Renfree, Marilyn B.

2008-01-01

46

Effects of Aspirin and Hypothermia on Platelet Function in Vivo.  

National Technical Information Service (NTIS)

Hypothermia, aspirin, and cardiopulmonary bypass can each induce a platelet function defect, but it is not known if the effects of aspirin and hypothermia are additive in this regard. To address this question in humans in vivo, the forearm skin temperatur...

A. D. Michelson M. R. Barnard S. F. Khuri M. J. Rohrer H. MacGregor

1997-01-01

47

Human myocardial ATP content and in vivo contractile function  

Microsoft Academic Search

The study was designed to characterize the relationship between the metabolise content of human cardiac muscle and in vivo cardiac function. ATP, total adenine nucleotides, and NAD were quantified in human myocardial biopsies using high performance liquid chromatography. Right ventricular endomyocardial biopsies were obtained from 43 patients with dilated cardiomyopathy, 6 with restrictive cardiomyopathy, 10 with normal systolic and diastolic

Randall C. Starling; Donald F. Hammer; Ruth A. Altschuld

1998-01-01

48

Time related changes in luteal prostaglandin synthesis and steroidogenic capacity during pregnancy, normal and antiprogestin induced luteolysis in the bitch  

Microsoft Academic Search

In nonpregnant and pregnant dogs the corpora lutea (CL) are the only source of progesterone (P4) which shows an almost identical secretion pattern until the rapid decrease of P4 prior to parturition. For the nonpregnant dog clear evidence has been obtained that physiological luteal regression is devoid of a functional role of the PGF2?-system and seems to depend on the

Mariusz Pawel Kowalewski; Hakki Bülent Beceriklisoy; Selim Aslan; Ali Reha Agaoglu; Bernd Hoffmann

2009-01-01

49

Menstrual disturbances in athletes: a focus on luteal phase defects.  

PubMed

Subtle menstrual disturbances that affect the largest proportion of physically active women and athletes include luteal phase defects (LPD). Disorders of the luteal phase, characterized by poor endometrial maturation as a result of inadequate progesterone (P4) production and short luteal phases, are associated with infertility and habitual spontaneous abortions. In recreational athletes, the 3-month sample prevalence and incidence rate of LPD and anovulatory menstrual cycles is 48% and 79%, respectively. A high proportion of active women present with LPD cycles in an intermittent and inconsistent manner. These LPD cycles are characterized by reduced follicle-stimulating hormone (FSH) during the luteal-follicular transition, a somewhat blunted luteinizing hormone surge, decreased early follicular phase estradiol excretion, and decreased luteal phase P4 excretion both with and without a shortened luteal phase. LPD cycles in active women are associated with a metabolic hormone profile indicative of a hypometabolic state that is similar to that observed in amenorrheic athletes but not as comprehensive or severe. These metabolic alterations include decreased serum total triiodothyronine (T3), leptin, and insulin levels. Bone mineral density in these women is apparently not reduced, provided an adequate estradiol environment is maintained despite decreased P4. The high prevalence of LPD warrants further investigation to assess health risks and preventive strategies. PMID:12972877

De Souza, Mary Jane

2003-09-01

50

Detection of Tight Junction Barrier Function In Vivo by Biotin  

PubMed Central

Tight junctions (TJs) are the most apical component of the junctional complexes in mammalian epithelial cells and form selective paracellular barriers restricting the passage of solutes and ions across the epithelial sheets. Claudins, a TJ integral membrane protein family, play a critical role in regulating paracellular barrier permeability. In the in vitro cell culture system, transepithelial electrical resistance (TER) measurement and the flux of radioisotope or fluorescent labeled molecules with different sizes have been widely used to determine the TJ barrier function. In the in vivo system, the tracer molecule Sulfo-NHS-Biotin was initially used in Xenopus embryos system and subsequently was successfully applied to a number of animal tissues in situ and in different organisms under the experimental conditions to examine the functional integrity of TJs by several laboratories. In this chapter, we will describe the detailed procedures of applying biotin as a paracellular tracer molecule to different in vivo systems to assay TJ barrier function.

Ding, Lei; Zhang, Yuguo; Tatum, Rodney; Chen, Yan-Hua

2011-01-01

51

Context-dependent function of "GATA switch" sites in vivo.  

PubMed

Master transcriptional regulators of development often function through dispersed cis elements at endogenous target genes. While cis-elements are routinely studied in transfection and transgenic reporter assays, it is challenging to ascertain how they function in vivo. To address this problem in the context of the locus encoding the critical hematopoietic transcription factor Gata2, we engineered mice lacking a cluster of GATA motifs 2.8 kb upstream of the Gata2 transcriptional start site. We demonstrate that the -2.8 kb site confers maximal Gata2 expression in hematopoietic stem cells and specific hematopoietic progenitors. By contrast to our previous demonstration that a palindromic GATA motif at the neighboring -1.8 kb site maintains Gata2 repression in terminally differentiating erythroid cells, the -2.8 kb site was not required to initiate or maintain repression. These analyses reveal qualitatively distinct functions of 2 GATA motif-containing regions in vivo. PMID:21398579

Snow, Jonathan W; Trowbridge, Jennifer J; Johnson, Kirby D; Fujiwara, Tohru; Emambokus, Nikla E; Grass, Jeffrey A; Orkin, Stuart H; Bresnick, Emery H

2011-03-11

52

Involvement of microtubules in lipoprotein degradation and utilization for steroidogenesis in cultured rat luteal cells  

SciTech Connect

Cells isolated from superovulated rat ovaries metabolize low density lipoprotein (LDL) and high density lipoprotein (HDL) of human or rat origin and use the lipoprotein-derived cholesterol as a precursor for progesterone production. Under in vitro conditions, both lipoproteins are internalized and degraded in the lysosomes, although degradation of HDL is of lower magnitude than that of LDL. In this report we have examined the role of cellular microtubules in the internalization and degradation of human LDL and HDL in cultured rat luteal cells. The microtubule depolymerizing agents colchicine, podophyllotoxin, vinblastine, and nocodazole as well as taxol, deuterium oxide, and dimethyl sulfoxide, which are known to rapidly polymerize cellular tubulin into microtubules, were used to block the function of microtubules. When these antimicrotubule agents were included in the incubations, degradation of the apolipoproteins of (/sup 125/I)iodo-LDL and (/sup 125/I)iodo-HDL by the luteal cells was inhibited by 50-85% compared to untreated control values. Maximum inhibitory effects were observed when the cells were preincubated with the inhibitor for at least 4 h at 37 C before treatment with the labeled lipoprotein. Lipoprotein-stimulated progesterone production by luteal cells was also inhibited by 50% or more in the presence of antimicrotubule agents. However, basal and hCG-stimulated progesterone production were unaffected by these inhibitors. The binding of (/sup 125/I)iodo-LDL and (/sup 125/I)iodo-HDL to luteal cell plasma membrane receptors was not affected by the microtubule inhibitors. Although binding was unaffected and degradation was impaired in the presence of the inhibitors, there was no detectable accumulation of undegraded lipoprotein within the cells during the 24 h of study.

Rajan, V.P.; Menon, K.M.

1985-12-01

53

Effects of testosterone and 5alpha-dihydrotestosterone on luteal lifespan in dairy heifers.  

PubMed

Endogenous concentrations of testosterone increase approximately 7 d prior to estrus in cattle and goats. Inhibition of testosterone synthesis results in a delay of luteal regression in both species. The purpose of this experiment was to determine if treatment with testosterone or 5alpha-dihydrotestosterone (DHT), 2 to 6 d prior to the endogenous rise in testosterone, would result in premature luteal regression. Sixteen heifers were randomly assigned to one of three treatment groups: 1) Control (n = 6); 2) testosterone (100 mug, n = 5); or 3) DHT (100 mug, n = 5). Each heifer received a single injection of the appropriate steriod on Day 8, 9, 10, 11 or 12 post estrus. Jugular venous blood samples were collected at frequent intervals for 24 h to quantify testosterone, and then daily for 14 d to quantify progesterone. Concentrations of testosterone increased within 15 min of injection of testosterone, and reached a maximum at 30 min. Concentrations were maintained at > 2 ng/ml throughout the first 24 h after injection. Based on concentrations of progesterone, neither androgen had any effect on the lifespan of the corpus luteum or the level of luteal function. PMID:16726733

Silvia, W J; Jacobs, A L; Hayes, S H

1989-11-01

54

Leucocyte phagocytosis during the luteal phase in bitches.  

PubMed

Pyometra is a disease that affects a large proportion of intact bitches, and typically is seen during the latter half of dioestrus. Several factors contribute to the development of pyometra, including genetic factors, an infectious component (most often Escherichia coli), and hormonal factors. Hormones may act directly on the endometrium, and also affect the immune system. In dogs, the phagocytic ability has been shown to decrease with age, and ovarian hormones have also been shown to affect immune resistance. The aim of the present study was to examine whether phagocytosis by canine leucocytes varies significantly during the luteal phase. Eight bitches were followed by repeated blood sampling. Samples were taken at the calculated optimal day for mating (Day 1), and thereafter on days 8, 15 and 22 (early luteal phase) and 29, 43, 57 and 71 (late luteal phase). Blood was collected from the cephalic vein into EDTA tubes for leucocyte counts and heparinised tubes for testing of phagocytosis and oxidative burst using commercial kits and flow cytometry. The cell activity of the phagocyting leucocytes, expressed as mean fluorescence activity, MFI, was significantly lower during late luteal phase than during early luteal phase. The proportion of leucocytes that was induced to phagocyte did not differ significantly. The percentage of cells stimulated by E. coli to oxidative burst was significantly lower during late luteal phase. Their activity did not differ between the two periods. The number of cells stimulated to oxidative burst by a low stimulus was too low to evaluate, and leucocytes stimulated with the high stimulus did not vary in oxidative burst between the two periods. The changes in phagocytic activity and in the number of leucocytes that showed oxidative burst were not associated with any change in the proportion of different leucocytes. The decreased phagocytic capacity possibly contributes to the higher incidence of diseases such as pyometra during the latter part of the luteal phase. PMID:23477931

Holst, Bodil Ström; Gustavsson, Malin Hagberg; Lilliehöök, Inger; Morrison, David; Johannisson, Anders

2013-02-13

55

Dendritic spines: from structure to in vivo function  

PubMed Central

Dendritic spines arise as small protrusions from the dendritic shaft of various types of neuron and receive inputs from excitatory axons. Ever since dendritic spines were first described in the nineteenth century, questions about their function have spawned many hypotheses. In this review, we introduce understanding of the structural and biochemical properties of dendritic spines with emphasis on components studied with imaging methods. We then explore advances in in vivo imaging methods that are allowing spine activity to be studied in living tissue, from super-resolution techniques to calcium imaging. Finally, we review studies on spine structure and function in vivo. These new results shed light on the development, integration properties and plasticity of spines.

Rochefort, Nathalie L; Konnerth, Arthur

2012-01-01

56

Functionalized Magnetic Nanoparticles as an In Vivo Delivery System  

NASA Astrophysics Data System (ADS)

We developed extremely small functionalized magnetic nanoparticles (MNPs) for use as an in vivo delivery system for pharmaceuticals and biomolecules. We functionalized the MNPs (d = 3 nm) by silanization of amino groups on the particles with (3-aminopropyl)triethoxysilane for subsequent cross-linking with pharmaceuticals and biomolecules. The MNPs were successfully introduced into living cells without any further modification, such as the use of cationic residues, to enhance endocytic internalization. The particles could be incorporated into the subcutaneous tissue of a mouse’s ear through the skin of the ear and could be localized by application of an external magnetic field.

Taira, Shu; Moritake, Shinji; Hatanaka, Takahiro; Ichiyanagi, Yuko; Setou, Mitsutoshi

57

Physiological functions of protein kinase D in vivo.  

PubMed

The cellular functions of the serine/threonine protein kinase D (PKD) have been extensively studied within the last decade and distinct roles such as fission of vesicles at the Golgi compartment, coordination of cell migration and invasion, and regulation of gene transcription have been correlated with this kinase family. Here, we highlight the current state of in vivo studies on PKD function with a focus on animal models and discuss the molecular basis of the observed phenotypic characteristics associated with this kinase family. PMID:23288632

Ellwanger, Kornelia; Hausser, Angelika

2013-01-03

58

Cyclin D1 Determines Mitochondrial Function In Vivo  

PubMed Central

The cyclin D1 gene encodes a regulatory subunit of the holoenzyme that phosphorylates and inactivates the pRb tumor suppressor to promote nuclear DNA synthesis. cyclin D1 is overexpressed in human breast cancers and is sufficient for the development of murine mammary tumors. Herein, cyclin D1 is shown to perform a novel function, inhibiting mitochondrial function and size. Mitochondrial activity was enhanced by genetic deletion or antisense or small interfering RNA to cyclin D1. Global gene expression profiling and functional analysis of mammary epithelial cell-targeted cyclin D1 antisense transgenics demonstrated that cyclin D1 inhibits mitochondrial activity and aerobic glycolysis in vivo. Reciprocal regulation of these genes was observed in cyclin D1-induced mammary tumors. Cyclin D1 thus integrates nuclear DNA synthesis and mitochondrial function.

Sakamaki, Toshiyuki; Casimiro, Mathew C.; Ju, Xiaoming; Quong, Andrew A.; Katiyar, Sanjay; Liu, Manran; Jiao, Xuanmao; Li, Anping; Zhang, Xueping; Lu, Yinan; Wang, Chenguang; Byers, Stephen; Nicholson, Robert; Link, Todd; Shemluck, Melvin; Yang, Jianguo; Fricke, Stanley T.; Novikoff, Phyllis M.; Papanikolaou, Alexandros; Arnold, Andrew; Albanese, Christopher; Pestell, Richard

2006-01-01

59

Microarray analysis of the primate luteal transcriptome during chorionic gonadotrophin administration simulating early pregnancy  

PubMed Central

To explore chorionic gonadotrophin (CG)-regulated gene expression in the primate corpus luteum (CL), adult female rhesus macaques were treated in a model of simulated early pregnancy (SEP). Total RNA was isolated from individual CL after specific intervals of exposure (1, 3, 6 and 9 days) to recombinant hCG in vivo and hybridized to Affymetrix™ GeneChip Rhesus Macaque Genome Arrays. The mRNA levels of 1192 transcripts changed ?2-fold [one-way ANOVA, false discovery rate (FDR) correction; P< 0.05] during SEP when compared with Day 10 untreated controls. Real-time PCR validation indicated that 15 of 17 genes matched in expression pattern between PCR and microarray. Protein levels of three genes identified as CG-sensitive, CYP19A1 (aromatase), PGRMC1 (progestin-binding protein) and STAR (steroidogenic acute regulatory protein) were quantified by western blot analysis. To further analyze global changes in gene expression induced by CG exposure, luteal gene expression was compared between SEP (rescued) and regressing CL, utilizing previously banked GeneChip data from the luteal phase of the menstrual cycle. Expression patterns and mRNA levels were analyzed between time-matched intervals. Transcripts for 7677 mRNAs differed in expression patterns ?2-fold (one-way ANOVA, FDR correction; P< 0.05) between the hCG-exposed (SEP) CL and regressing CL. Regressed CL (at menses) were most unlike all other CL. Pathway analysis of significantly affected transcripts was performed; the pathway most impacted by CG exposure was steroid biosynthesis. Further comparisons of the genome-wide changes in luteal gene expression during CG rescue and luteolysis in the natural menstrual cycle should identify additional key regulatory pathways promoting primate fertility.

Bishop, C.V.; Satterwhite, S.; Xu, L.; Hennebold, J.D.; Stouffer, R.L.

2012-01-01

60

Plasma gonadotrophin and ovarian steroid concentrations in women with menstrual cycles with a short luteal phase  

Microsoft Academic Search

Summary. Daily plasma concentrations of FSH, LH, oestradiol-17\\\\g=b\\\\and progesterone were compared for 12 cycles with a short luteal phase and 19 cycles with a luteal phase of normal length (i.e. cycles in which the luteal phase lasted 12 or more days). FSH and LH concentrations were suppressed in short luteal-phase cycles in the early follicular phase and the length of

S. K. Smith; Elizabeth A. Lenton; I. D. Cooke

1985-01-01

61

The luteal phase after 3 decades of IVF: what do we know?  

Microsoft Academic Search

The luteal phases of all stimulated IVF cycles are abnormal. The main cause of the luteal phase defect (LPD) observed in stimulated IVF cycles is related to the multifollicular development achieved during ovarian stimulation. This may be related to the supra-physiological concentrations of steroids secreted by a high number of corpora lutea during the early luteal phase, which directly inhibit

HM Fatemi

2009-01-01

62

Neurovascular coupling: in vivo optical techniques for functional brain imaging.  

PubMed

Optical imaging techniques reflect different biochemical processes in the brain, which is closely related with neural activity. Scientists and clinicians employ a variety of optical imaging technologies to visualize and study the relationship between neurons, glial cells and blood vessels. In this paper, we present an overview of the current optical approaches used for the in vivo imaging of neurovascular coupling events in small animal models. These techniques include 2-photon microscopy, laser speckle contrast imaging (LSCI), voltage-sensitive dye imaging (VSDi), functional photoacoustic microscopy (fPAM), functional near-infrared spectroscopy imaging (fNIRS) and multimodal imaging techniques. The basic principles of each technique are described in detail, followed by examples of current applications from cutting-edge studies of cerebral neurovascular coupling functions and metabolic. Moreover, we provide a glimpse of the possible ways in which these techniques might be translated to human studies for clinical investigations of pathophysiology and disease. In vivo optical imaging techniques continue to expand and evolve, allowing us to discover fundamental basis of neurovascular coupling roles in cerebral physiology and pathophysiology. PMID:23631798

Liao, Lun-De; Tsytsarev, Vassiliy; Delgado-Martínez, Ignacio; Li, Meng-Lin; Erzurumlu, Reha; Vipin, Ashwati; Orellana, Josue; Lin, Yan-Ren; Lai, Hsin-Yi; Chen, You-Yin; Thakor, Nitish V

2013-04-30

63

Imaging visual cortical structure and function in vivo.  

PubMed

The recent advent of in vivo two-photon microscopy has allowed the repeat imaging of cortical structures at microscopic resolution within intact brains. Recent data obtained using this imaging technique shows that dendritic spines, the postsynaptic sites of the majority of excitatory synapses in the central nervous system (CNS), rapidly remodel in response to changes in the visual environment. We combined two-photon microscopy of dendritic segments with intrinsic signal imaging of visual cortical responses in the developing ferret visual cortex, and showed that when one eye was deprived during the developmental critical period for ocular dominance plasticity, both dendritic spines and visual responses to the deprived eye were rapidly altered. A brief period of recovery where the eye was re-opened resulted in a return to pre-deprivation levels for both responses and dendritic spine density, showing that structural and functional changes are linked even at very rapid timescales. Additionally, two-photon microscopy can assay other functional and structural aspects of visual cortical function which I will review. Lastly, I will compare this technique to other imaging modalities available for assessment of the visual cortex in vivo. PMID:23733120

Majewska, Ania K

64

The clinical relevance of luteal phase deficiency: a committee opinion.  

PubMed

Luteal phase deficiency (LPD) has been described in healthy normally menstruating women and in association with other medical conditions. While progesterone is important for the process of implantation and early embryonic development, LPD, as an independent entity causing infertility, has not been proven. PMID:22819186

2012-07-20

65

Follicular and luteal phase characteristics following early cessation of gonadotrophin-releasing hormone agonist during ovarian stimulation for in-vitro fertilization  

Microsoft Academic Search

Gonadotrophin-releasing hormone agonists (GnRHa) are widely used in\\u000a in-vitro fertilization (IVF) for the prevention of a premature rise in\\u000a luteinizing hormone (LH) concentrations. However, the administration of\\u000a GnRHa during the follicular phase may also impair subsequent luteal\\u000a function due to retarded recovery of pituitary gonadotrophin secretion.\\u000a Therefore, luteal supplementation is generally applied. The present study\\u000a was designed to determine whether

J. S. E. Laven; M. J. C. Eijkemans; B. C. J. M. Fauser; N. G. M. Beckers

2000-01-01

66

Use of photoproteins for in-vivo functional imaging  

NASA Astrophysics Data System (ADS)

The relative opacity of mammalian tissue permits the transmission of light from internal biological light sources in small laboratory animals. As such internally expressed bioluminescence can be detected externally revealing spatiotemporal information about tagged biological functions. Enzymes that emit light, photoproteins, have been characterized photoproteins have been used as reporters in a variety of in vitro and ex vivo assays and are now being employed as sources of internal biological light that can be eternally monitored in living animals. Using this approach, spatiotemporal changes in patterns of gene expression, infectious disease and tumor cell growth can be revealed in real time. Monitoring light emissions from internal sources provides a powerful method for cellular and molecular analyses in living animals. This approach is particularly well suited for the evaluation of potential therapeutics including the efficacy of novel DNA-based therapies and vaccines.

Contag, Christopher H.

1999-07-01

67

In vivo minimally invasive interstitial multi-functional microendoscopy  

NASA Astrophysics Data System (ADS)

Developing minimally invasive methodologies for imaging of internal organs is an emerging field in the biomedical examination research. This paper introduces a new multi-functional microendoscope device capable of imaging of internal organs with a minimal invasive intervention. In addition, the developed microendoscope can also be employed as a monitoring device for measuring local hemoglobin concentration in blood stream when administrated into a blood artery. The microendoscope device has a total external diameter of only 200 ?m and can provide high imaging resolution capability of more than 5,000 pixels. The device can detect features with a spatial resolution of less than 1 ?m. The microendoscope has been tested both in-vitro as well as in-vivo in rats presenting a promising and powerful tool as a high resolution and minimally invasive imaging facility suitable for previously unreachable clinical modalities.

Shahmoon, Asaf; Aharon, Shiran; Kruchik, Oded; Hohmann, Martin; Slovin, Hamutal; Douplik, Alexandre; Zalevsky, Zeev

2013-05-01

68

Emerging In Vivo Analyses of Cell Function Using Fluorescence Imaging?  

PubMed Central

Understanding how cells of all types sense external and internal signals and how these signals are processed to yield particular responses is a major goal of biology. Genetically encoded fluorescent proteins (FPs) and fluorescent sensors are playing an important role in achieving this comprehensive knowledge base of cell function. Providing high sensitivity and immense versatility while being minimally perturbing to a biological specimen, the probes can be used in different microscopy techniques to visualize cellular processes on many spatial scales. Three review articles in this volume discuss recent advances in probe design and applications. These developments help expand the range of biochemical processes in living systems suitable for study. They provide researchers with exciting new tools to explore how cellular processes are organized and their activity regulated in vivo.

Lippincott-Schwartz, Jennifer

2013-01-01

69

Fertility in a high-altitude environment is compromised by luteal dysfunction: the relative roles of hypoxia and oxidative stress  

PubMed Central

Background At high altitudes, hypoxia, oxidative stress or both compromise sheep fertility. In the present work, we tested the relative effect of short- or long-term exposure to high altitude hypobaric hypoxia and oxidative stress on corpora luteal structure and function. Methods The growth dynamics of the corpora lutea during the estrous cycle were studied daily by ultrasonography in cycling sheep that were either native or naïve to high-altitude conditions and that were supplemented or not supplemented with antioxidant vitamins. Arterial and venous blood samples were simultaneously drawn for determination of gases and oxidative stress biomarkers and progesterone measurement. On day five after ovulation in the next cycle, the ovaries were removed for immunodetection of luteal HIF-1alpha and VEGF and IGF-I and to detect IGF-II gene expression. Results The results showed that both short- and long-term exposure to high-altitude conditions decreased luteal growth and IGF-I and IGF-II gene expression but increased HIF-1 alpha and VEGF immunoexpression. The level of plasma progesterone was also increased at a high altitude, although an association with increased corpus luteum vascularization was only found in sheep native to a high-altitude location. Administration of antioxidant vitamins resulted in a limited effect, which was restricted to decreased expression of oxidative stress biomarkers and luteal HIF-1alpha and VEGF immunoexpression. Conclusions Exposure of the sheep to high-altitude hypobaric hypoxia for short or long time periods affects the development and function of the corpus luteum. Moreover, the observed association of oxidative stress with hypoxia and the absence of any significant effect of antioxidant vitamins on most anatomical and functional corpus luteum traits suggests that the effects of high altitude on this ovarian structure are mainly mediated by hypoxia. Thus, these findings may help explain the decrease in sheep fertility at a high altitude.

2013-01-01

70

Effects of the 3?-hydroxysteroid dehydrogenase inhibitor trilostane on luteal progesterone production in the dog.  

PubMed

Interference with the pregnancy-maintaining influence of progesterone is the basis of most methods for termination of unwanted pregnancy in dogs. The currently available methods are based on induction of luteolysis or blocking of the progesterone receptor. Inhibition of progesterone synthesis using a competitive inhibitor of 3?-hydroxysteroid dehydrogenase (3?-HSD) could be another strategy to terminate unwanted pregnancies. In this study we investigated the effects of the 3?-HSD inhibitor trilostane on corpus luteum function in non-pregnant bitches. Trilostane was administered orally for seven consecutive days in either the pituitary-independent part of the luteal phase (PIP, start of treatment on D11 after ovulation, n = 6) or the pituitary-dependent part (PDP, start of treatment on D31 after ovulation, n = 6), in an oral dose of about 4.5 mg/kg bw, twice daily. Results were compared with those obtained in control bitches (n = 6). ACTH stimulation tests were performed to assess adrenocortical reserve capacity. Trilostane caused no apparent side effects and ACTH stimulation tests revealed good suppression of cortisol secretion. Trilostane also caused a significant decrease in plasma progesterone concentration. When it was stopped during PIP, progesterone secretion was completely restored and there was no difference in the length of the luteal phase between those dogs and control dogs (99 days, range 70-138 d and 99 d, range 60-112 d, respectively). When trilostane was stopped during PDP there was no post-treatment recovery of progesterone secretion and although the luteal phase tended to be shorter (66 d, range 41-101 d) the difference was not significant (P = 0.09). Plasma prolactin concentration did not increase after the trilostane-induced decrease in plasma progesterone. The interoestrous interval in dogs treated during PIP (234 d, range 175-269 d) or PDP (198 d, range 120-287 d) was not significantly shorter than the control interval (247 d, range 176-313 d). In conclusion, trilostane treatment was effective in decreasing plasma progesterone concentration in bitches during the luteal phase, but the dose regimen used in this study produced less clear-cut inhibition of ovarian steroidogenesis than have other strategies to decrease plasma progesterone concentration. Further studies are warranted to determine whether trilostane can be used to terminate unwanted pregnancy in the bitch without inducing adrenocortical insufficiency. PMID:21295836

de Gier, J; Wolthers, C H J; Galac, S; Okkens, A C; Kooistra, H S

2011-02-04

71

Function and specificity of synthetic Hox transcription factors in vivo  

PubMed Central

Homeotic (Hox) genes encode transcription factors that confer segmental identity along the anteroposterior axis of the embryo. However the molecular mechanisms underlying Hox-mediated transcription and the differential requirements for specificity in the regulation of the vast number of Hox-target genes remain ill-defined. Here we show that synthetic Sex combs reduced (Scr) genes that encode the Scr C terminus containing the homedomain (HD) and YPWM motif (Scr-HD) are functional in vivo. Synthetic Scr-HD peptides can induce ectopic salivary glands in the embryo and homeotic transformations in the adult fly, act as transcriptional activators and repressors during development, and participate in protein-protein interactions. Their transformation capacity was found to be enhanced over their full-length counterpart and mutations known to transform the full-length protein into constitutively active or inactive variants behaved accordingly in the synthetic peptides. Our results show that synthetic Scr-HD genes are sufficient for homeotic function in Drosophila and suggest that the N terminus of Scr has a role in transcriptional potency, rather than specificity. We also demonstrate that synthetic peptides behave largely in a predictable way, by exhibiting Scr-specific phenotypes throughout development, which makes them an important tool for synthetic biology.

Papadopoulos, Dimitrios K.; Vukojevic, Vladana; Adachi, Yoshitsugu; Terenius, Lars; Rigler, Rudolf; Gehring, Walter J.

2010-01-01

72

Degradation of high density lipoprotein in cultured rat luteal cells  

SciTech Connect

In rat ovary luteal cells, degradation of high density lipoprotein (HDL) to tricholoracetic acid (TCA)-soluble products accounts for only a fraction of the HDL-derived cholesterol used for steroidogenesis. In this study the authors have investigated the fate of /sup 125/I)HDL bound to cultured luteal cells using pulse-chase technique. Luteal cell cultures were pulse labeled with (/sup 125/I)HDL/sub 3/ and reincubated in the absence of HDL. By 24 h about 50% of the initallay bound radioactivity was released into the medium, of which 60-65% could be precipitated with 10% TCA. Gel filtration of the chase incubation medium on 10% agarose showed that the amount of TCA-soluble radioactivity was nearly completely accounted for by a sharp peak in the low molecular weight region which was identified as 96% monoiodotyrosine by paper chromatography. The TCA-precipitable radioactivity was nearly completely accounted for by a sharp peak in the low molecular weight region which was identified as 96% monoiodotyrosine by paper chromatography. The TCA-precipitable radioactivity eluted over a wide range of molecular weights (15,000-80,000), and there was very little intact HDL present. Electrophoresis of the chase medium showed that component of the TCA-precipitable portion had mobility similar to apo AI. Lysosomal inhibitors of receptor-mediated endocytosis had no effect on the composition or quantity of radioactivity released during chase incubation. The results show that HDL/sub 3/ binding to luteal cells is followed by complete degradation of the lipoprotein, although the TCA-soluble part does not reflect the extent of degradation.

Rajan, V.P.; Menon, K.M.J.

1986-03-01

73

DHA-enriched fish oil targets B cell lipid microdomains and enhances ex vivo and in vivo B cell function.  

PubMed

DHA is a n-3 LCPUFA in fish oil that generally suppresses T lymphocyte function. However, the effect of fish oil on B cell function remains relatively understudied. Given the important role of B cells in gut immunity and increasing human fish oil supplementation, we sought to determine whether DFO leads to enhanced B cell activation in the SMAD-/- colitis-prone mouse model, similar to that observed with C57BL/6 mice. This study tested the hypothesis that DHA from fish oil is incorporated into the B cell membrane to alter lipid microdomain clustering and enhance B cell function. Purified, splenic B cells from DFO-fed mice displayed increased DHA levels and diminished GM1 microdomain clustering. DFO enhanced LPS-induced B cell secretion of IL-6 and TNF-? and increased CD40 expression ex vivo compared with CON. Despite increased MHCII expression in the unstimulated ex vivo B cells from DFO-fed mice, we observed no difference in ex vivo OVA-FITC uptake in B cells from DFO or CON mice. In vivo, DFO increased lymphoid tissue B cell populations and surface markers of activation compared with CON. Finally, we investigated whether these ex vivo and in vivo observations were consistent with systemic changes. Indeed, DFO-fed mice had significantly higher plasma IL-5, IL-13, and IL-9 (Th2-biasing cytokines) and cecal IgA compared with CON. These results support the hypothesis and an emerging concept that fish oil enhances B cell function in vivo. PMID:23180828

Gurzell, Eric A; Teague, Heather; Harris, Mitchel; Clinthorne, Jonathan; Shaikh, Saame Raza; Fenton, Jenifer I

2012-11-24

74

Inflammation Modulates Human HDL Composition and Function in vivo  

PubMed Central

Objectives Inflammation may directly impair HDL functions, in particular reverse cholesterol transport (RCT), but limited data support this concept in humans. Methods and Results We employed low-dose human endotoxemia to assess the effects of inflammation on HDL and RCT-related parameters in vivo. Endotoxemia induced remodelling of HDL with depletion of pre-?1a HDL particles determined by 2-D gel electrophoresis (-32.2 ± 9.3% at 24h, p<0.05) as well as small (-23.0 ± 5.1%, p<0.01, at 24h) and medium (-57.6 ± 8.0% at 16h, p<0.001) HDL estimated by nuclear magnetic resonance (NMR). This was associated with induction of class II secretory phospholipase A2 (~36 fold increase) and suppression of lecithin:cholesterol acyltransferase activity (-20.8 ± 3.4% at 24h, p<0.01) and cholesterol ester transfer protein mass (-22.2 ± 6.8% at 24h, p<0.001). The HDL fraction, isolated following endotoxemia, had reduced capacity to efflux cholesterol in vitro from SR-BI and ABCA1, but not ABCG1 transporter cell models. Conclusions These data support the concept that “atherogenic-HDL dysfunction” and impaired RCT occur in human inflammatory syndromes, largely independent of changes in plasma HDL-C and ApoA-I levels.

de la Llera Moya, Margarita; McGillicuddy, Fiona C; Hinkle, Christine C; Byrne, Michael; Joshi, Michelle R; Nguyen, Vihn; Tabita-Martinez, Jennifer; Wolfe, Megan L; Badellino, Karen; Pruscino, Leticia; Mehta, Nehal N; Asztalos, Bela F; Reilly, Muredach P

2012-01-01

75

Transplanted CNS stem cells form functional synapses in vivo.  

PubMed

An understanding of developmental mechanisms and new cell therapies can be achieved by transplantation into the nervous system. Multipotential stem cells have been isolated from the foetal and adult central nervous system (CNS). Immortalized and primary precursor cells integrate into the developing brain generating both neurons and glia as defined by immunological and morphological criteria. Here we show for the first time that in vitro-expanded CNS precursors, upon transplantation into the brains of rats, form electrically active and functionally connected neurons. These neurons exhibit spontaneous and evoked postsynaptic events and respond to focal glutamate application. Donor cells were grafted into the foetal hippocampus, and the amplitude and frequency of spontaneous synaptic events were monitored in the grafted cells in area CA1 for the first month of postnatal life. The formation of synapses onto grafted neurons indicates that grafted CNS stem cells can be used to study synaptic development in vivo and has important implications for clinical cell replacement therapies. PMID:10792447

Auerbach, J M; Eiden, M V; McKay, R D

2000-05-01

76

Proteomic Analysis of the Luteal Endometrial Secretome  

PubMed Central

Endometrium attains a secretory architecture in preparation for embryo implantation, but the identity of most endometrial secretory products remains unknown. Our objective was to characterize the endometrial secretome and compare protein expression between prereceptive (luteinizing hormone [LH]+4) receptive (LH+9) and phase endometrium. Endometrial lavage was performed in 11 participants and analyzed by difference gel electrophoresis (DIGE). LH+4 and LH+9 specimens were labeled with cyanine fluorescent dyes Cy3 and Cy5 tags, respectively, and combined. Proteins were separated using 2-dimensional gel electrophoresis, isolated, trypsin-digested, and subjected to mass spectrometry. In all, 152 proteins were identified; 82 were differentially expressed. Most proteins with increased expression on LH+9 functioned in host defense, while proteins with decreased expression had many functions. A total of 14 proteins had changes suggesting altered posttranslational modification. This article describes the first application of proteomic analysis to endometrial secretions, allowing identification of novel endometrial proteins as well as those differentially secreted in prereceptive and receptive phases.

Scotchie, Jessica G.; Fritz, Marc A.; Mocanu, Mihaela; Lessey, Bruce A.; Young, Steven L.

2010-01-01

77

Roles of prostaglandin F2alpha and hydrogen peroxide in the regulation of Copper/Zinc superoxide dismutase in bovine corpus luteum and luteal endothelial cells  

PubMed Central

Background Prostaglandin F2alpha (PGF) induces luteolysis in cow by inducing a rapid reduction in progesterone production (functional luteolysis) followed by tissue degeneration (structural luteolysis). However the mechanisms of action of PGF remain unclear. Reactive oxygen species (ROS) play important roles in regulating the luteolytic action of PGF. The local concentration of ROS is controlled by superoxide dismutase (SOD), the main enzyme involved in the control of intraluteal ROS. Thus SOD seems to be involved in luteolysis process induced by PGF in cow. Methods To determine the dynamic relationship between PGF and ROS in bovine corpus luteum (CL) during luteolysis, we determined the time-dependent change of Copper/Zinc SOD (SOD1) in CL tissues after PGF treatment in vivo. We also investigated whether PGF and hydrogen peroxide (H2O2) modulates SOD1 expression and SOD activity in cultured bovine luteal endothelial cells (LECs) in vitro. Results Following administration of a luteolytic dose of PGF analogue (0 h) to cows at the mid-luteal stage, the expression of SOD1 mRNA and protein, and total SOD activity in CL tissues increased between 0.5 and 2 h, but fell below the initial (0 h) level at 24 h post-treatment. In cultured LECs, the expression of SOD1 mRNA was stimulated by PGF (1–10 microM) and H2O2 (10–100 microM) at 2 h (P<0.05). PGF and H2O2 increased SOD1 protein expression and total SOD activity at 2 h (P<0.05), whereas PGF and H2O2 inhibited SOD1 protein expressions and total SOD activity at 24 h (P<0.05). In addition, H2O2 stimulated PGF biosynthesis at 2 and 24 h in bovine LECs. Overall results indicate that, SOD is regulated by PGF and ROS in bovine LECs. SOD may play a role in controlling intraluteal PGF and ROS action during functional and structural luteolysis in cows.

2012-01-01

78

The antiprogesterone steroid RU-486 does not impair gonadotropin-stimulated luteal adenylyl cyclase activity or gonadotropin release by pituitary cells.  

PubMed

Administration of the antiprogesterone synthetic steroid RU-486 (17 beta-hydroxy-11 beta-[4-dimethylaminophenyl-1]-17 alpha-[prop-l-ynyl]-estra-4,9-dien-3-one) in human and non-human primates induces menstruation and is promising as a new approach to fertility control. To explore the sites of action of RU-486, we investigated in this study the effects of RU-486 upon gonadotropin-stimulable adenylyl cyclase in membrane preparations obtained from human corpus luteum and upon LH and FSH release by a dispersed rat anterior pituitary cell culture. In the presence of a wide range of concentrations (10(-10) to 10(-6) M), RU-486 failed to alter basal or hCG-stimulated adenylyl cyclase activities under conditions allowing either maximal or submaximal hormonal activation. Additionally, enzyme stimulation by GMP-P(NH)P (100 microM), NaF (10 mM) or forskolin (100 microM) was not affected by a high concentration (10(-6) M) of RU-486. These data indicate that RU-486 does not affect gonadotropin receptor binding nor does it interfere with cAMP generation. It is unlikely, therefore, that the compound may modulate human luteal function through changes in plasma membrane lipid mobility or modifications of reactions occurring in plasma membranes as suggested for other steroids in several membrane systems. The present observations are compatible with previously published in vivo studies suggesting that RU-486 activity does not involve a direct antigonadotropic effect at the primate corpus luteum level. We also found that RU-486 (10(-12) to 10(-7) M) did not alter the basal release of gonadotropins by the pituitary cells, nor did the compound impair the response of these cells to maximally or submaximally effective concentrations of LHRH. Thus, these data suggest that the anti-reproductive actions of RU-486 involve no direct effect upon pituitary function. Taken together, these findings support the concept that RU-486 exerts its effects on the luteal phase exclusively by a local action upon the endometrium. PMID:3937946

Rojas, F J; O'Conner, J L; Asch, R H

1985-12-01

79

Impact of ovarian stimulation on mid-luteal endometrial tissue and secretion markers of receptivity  

Microsoft Academic Search

The objective of this study was to investigate the effect of ovarian stimulation for IVF on endometrial secretion and tissue markers of receptivity in the mid-luteal phase. In 10 oocyte donors, endometrial secretions and biopsies were sampled 5 days after spontaneous ovulation and oocyte retrieval in consecutive cycles. Four subjects received progesterone in the luteal phase of the stimulated cycles.

MH van der Gaast; I Classen-Linke; CA Krusche; K Beier-Hellwig; BCJM Fauser; HM Beier; NS Macklon

2008-01-01

80

Human corpus luteum physiology and the luteal-phase dysfunction associated with ovarian stimulation  

Microsoft Academic Search

The human corpus luteum is a temporary endocrine gland that develops after ovulation from the ruptured follicle during the luteal phase. It is an important contributor of steroid hormones, particularly progesterone, and is critical for the maintenance of early pregnancy. Luteal-phase dysfunction can result in premature regression of the gland, with a subsequent shift to an infertile cycle. Understanding the

Luigi Devoto; Paulina Kohen; Alex Muñoz; Jerome F Strauss III

2009-01-01

81

In vivo function of the craniofacial haft: The interorbital ?pillar?  

Microsoft Academic Search

The craniofacial haft resists forces gener- ated in the face during feeding, but the importance of these forces for the form of the craniofacial haft remains to be determined. In vivo bone strain data were recorded from the medial orbital wall in an owl monkey (Aotus), rhesus macaques (Macaca mulatta), and a galago (Otole- mur) during feeding. These data were

Callum F. Ross

2001-01-01

82

LUTEAL FUNCTION IN GILTS AFTER PROSTAGLANDIN F2~ I ,2  

Microsoft Academic Search

SUMMARY Twenty 9-month-old crossbred gilts were randomly allotted to one of four treatment groups to examine the effects of prostaglandin F2~ (PGF2a) on estrous cycle length, plasma progesterone, estradiol and LH. Two groups were injected four times intramuscularly at 12-hr intervals starting on day 4 of the estrous cycle with either a total of 80 mg PGF2~ or saline. The

D. M. Hallford; R. P. Wettemann; E. J. Turman; I. T. Omtvedt

83

LUTEAL FUNCTION IN THE HYSTERECTOMIZED PREPUBERAL GI LT t  

Microsoft Academic Search

SUMMARY The effect of hysterectomy on maintenance of induced corpora lutea (CL) in prepuberal gilts, 130 to 140 days of age, was studied. Ovulation was induced with 750 IU PMSG followed 72 hr later with 500 IU HCG (Day following HCG = Day 0). Ten gilts were bilaterally hysterectomized on Day 6 to 10, while 10 gilts (controls) were artificially

George B. Rampacek; Robert R. Kraeling; G. David Ball; Ricbard B. Russell

2010-01-01

84

Diesel exhaust particulate induces pulmonary and systemic inflammation in rats without impairing endothelial function ex vivo or in vivo  

PubMed Central

Background Inhalation of diesel exhaust impairs vascular function in man, by a mechanism that has yet to be fully established. We hypothesised that pulmonary exposure to diesel exhaust particles (DEP) would cause endothelial dysfunction in rats as a consequence of pulmonary and systemic inflammation. Methods Wistar rats were exposed to DEP (0.5 mg) or saline vehicle by intratracheal instillation and hind-limb blood flow, blood pressure and heart rate were monitored in situ 6 or 24 h after exposure. Vascular function was tested by administration of the endothelium-dependent vasodilator acetylcholine (ACh) and the endothelium-independent vasodilator sodium nitroprusside (SNP) in vivo and ex vivo in isolated rings of thoracic aorta, femoral and mesenteric artery from DEP exposed rats. Bronchoalveolar lavage fluid (BALF) and blood plasma were collected to assess pulmonary (cell differentials, protein levels & interleukin-6 (IL-6)) and systemic (IL-6), tumour necrosis factor alpha (TNF?) and C-reactive protein (CRP)) inflammation, respectively. Results DEP instillation increased cell counts, total protein and IL-6 in BALF 6 h after exposure, while levels of IL-6 and TNF? were only raised in blood 24 h after DEP exposure. DEP had no effect on the increased hind-limb blood flow induced by ACh in vivo at 6 or 24 h. However, responses to SNP were impaired at both time points. In contrast, ex vivo responses to ACh and SNP were unaltered in arteries isolated from rats exposed to DEP. Conclusions Exposure of rats to DEP induces both pulmonary and systemic inflammation, but does not modify endothelium-dependent vasodilatation. Other mechanisms in vivo limit dilator responses to SNP and these require further investigation.

2012-01-01

85

Rapid in vivo functional analysis of transgenes in mice using whole body imaging of luciferase expression  

Microsoft Academic Search

The use of transgenic animals in biomedical research is increasing rapidly and may be the best means of determining gene function. Generating transgenic animals typically requires time-consuming screening processes, and gene function is assessed by an array of difficult phenotypic and biochemical assays performed ex vivo. To address the unmet need in transgenic research for functional assays performed with ease

Weisheng Zhang; Jian Q. Feng; Stephen E. Harris; Pamela R. Contag; David K. Stevenson; Christopher H. Contag

2001-01-01

86

Nitric Oxide Effects on the Function of Aged Cells Ex Vivo and In Vivo  

PubMed Central

Background Angiogenesis is impaired in most aged tissues. Accordingly, there is great interest in interventions that improve the ability of aged cells to undergo blood vessel formation and subsequent tissue repair. Materials and Methods Nitric oxide (NO), a mediator proposed to enhance angiogenesis, was administered (as the precursor SNAP, S-nitroso-N-acetylpenicillamine) to aortic ring explants from aged mice and to aged mice in two separate in vivo experiments; a PVA sponge implant model of angiogenesis and full thickness excisional dermal wounds. Results SNAP inhibited angiogenesis from the mouse aortic ring explants. However, there was a trend toward increased blood vessel formation in the sponges from the aged mice treated with SNAP. SNAP did not detectably enhance dermal wound healing or angiogenesis, but it significantly inhibited epidermal closure. Conclusion These data underscore the complexity of using a single agent, even one with multiple mechanisms such as NO, to improve a clinical outcome such as angiogenesis or wound repair in aged animals.

Reed, May J.; Eyman, Daniel; Karres, Nathan

2009-01-01

87

In vitro gene regulatory networks predict in vivo function of liver  

PubMed Central

Background Evolution of toxicity testing is predicated upon using in vitro cell based systems to rapidly screen and predict how a chemical might cause toxicity to an organ in vivo. However, the degree to which we can extend in vitro results to in vivo activity and possible mechanisms of action remains to be fully addressed. Results Here we use the nitroaromatic 2,4,6-trinitrotoluene (TNT) as a model chemical to compare and determine how we might extrapolate from in vitro data to in vivo effects. We found 341 transcripts differentially expressed in common among in vitro and in vivo assays in response to TNT. The major functional term corresponding to these transcripts was cell cycle. Similarly modulated common pathways were identified between in vitro and in vivo. Furthermore, we uncovered the conserved common transcriptional gene regulatory networks between in vitro and in vivo cellular liver systems that responded to TNT exposure, which mainly contain 2 subnetwork modules: PTTG1 and PIR centered networks. Interestingly, all 7 genes in the PTTG1 module were involved in cell cycle and downregulated by TNT both in vitro and in vivo. Conclusions The results of our investigation of TNT effects on gene expression in liver suggest that gene regulatory networks obtained from an in vitro system can predict in vivo function and mechanisms. Inhibiting PTTG1 and its targeted cell cyle related genes could be key machanism for TNT induced liver toxicity.

2010-01-01

88

Effects of GnRH or progesterone treatment on day 5 post-AI on plasma progesterone, luteal blood flow and leucocyte counts during the luteal phase in dairy cows.  

PubMed

This study was designed to test the effects of progesterone or GnRH treatment on day 5 post-AI on fertility and luteal function in dairy cows and heifers. Five days after AI, 32 animals were randomly assigned to a control, intravaginal progesterone for 14 days progesterone releasing intravaginal device (PRID) or GnRH treatment group. On days 5, 7, 12, 14, 17 and 19 post-AI, each animal underwent colour Doppler ultrasonography of the corpus luteum and blood samples were collected for cell counts and plasma progesterone determination. Through general linear model repeated measures analysis of variance, significant effects were observed of treatment, parity, inseminating bull, reduced vascularization of the CL and pregnancy on plasma progesterone concentrations, whereas mean plasma progesterone and time luteal phase day, and treatment and plasma progesterone concentration on day 5 post-AI were found to, respectively, affect neutrophil and lymphocyte counts throughout the luteal phase. Moreover, two binary logistic regression analyses were performed. Based on the odds ratio, the likelihood of pregnancy by days 26-32 post-AI was 23.4 times higher in animals with high mean progesterone levels throughout the study period, compared with animals with low mean progesterone. The likelihood of reduced CL vascularization was 14 times higher in animals treated with PRID, compared with control and GnRH-treated animals. In conclusion, our results indicate that treatment on day 5 post-AI with PRID reduced subsequent CL vascularization, whereas GnRH treatment increased plasma progesterone concentrations on day 12 post-AI, although an effect was identified of the inseminating bull on plasma progesterone levels. Pregnant animals showed higher mean plasma progesterone concentrations than in nonpregnant ones and heifers higher than in lactating cows, whereas blood cell counts differed depending on the treatment and on the mean plasma progesterone concentration on day 5 post-AI. PMID:21729177

Garcia-Ispierto, I; López-Gatius, F

2011-07-05

89

Resurrection of DNA Function In Vivo from an Extinct Genome  

Microsoft Academic Search

There is a burgeoning repository of information available from ancient DNA that can be used to understand how genomes have evolved and to determine the genetic features that defined a particular species. To assess the functional consequences of changes to a genome, a variety of methods are needed to examine extinct DNA function. We isolated a transcriptional enhancer element from

Andrew J. Pask; Richard R. Behringer; Marilyn B. Renfree; Erik I. Svensson

2008-01-01

90

Cyclin D1 Determines Mitochondrial Function In Vivo  

Microsoft Academic Search

The cyclin D1 gene encodes a regulatory subunit of the holoenzyme that phosphorylates and inactivates the pRb tumor suppressor to promote nuclear DNA synthesis. cyclin D1 is overexpressed in human breast cancers and is sufficient for the development of murine mammary tumors. Herein, cyclin D1 is shown to perform a novel function, inhibiting mitochondrial function and size. Mitochondrial activity was

Toshiyuki Sakamaki; Mathew C. Casimiro; Xiaoming Ju; Andrew A. Quong; Sanjay Katiyar; Manran Liu; Xuanmao Jiao; Anping Li; Xueping Zhang; Yinan Lu; Chenguang Wang; Stephen Byers; Robert Nicholson; Todd Link; Melvin Shemluck; Jianguo Yang; Stanley T. Fricke; Phyllis M. Novikoff; Alexandros Papanikolaou; Andrew Arnold; Christopher Albanese; Richard Pestell

2006-01-01

91

In vivo functional imaging of human cone photoreceptors  

PubMed Central

We evaluate a novel non-invasive optical technique for observing fast physiological processes, in particular phototransduction, in single photoreceptor cells in the living human eye. The method takes advantage of the interference of multiple reflections within the outer segments (OS) of cones. This self-interference phenomenon is highly sensitive to phase changes such as those caused by variations in refractive index and scatter within the photoreceptor cell. A high-speed (192 Hz) flood-illumination retina camera equipped with adaptive optics (AO) is used to observe individual photoreceptors, and to monitor changes in their reflectance in response to visible stimuli (“scintillation”). AO and high frame rates are necessary for resolving individual cones and their fast temporal dynamics, respectively. Scintillation initiates within 5 to 10 ms after the onset of the stimulus flash, lasts 300 to 400 ms, is observed at visible and near-infrared (NIR) wavelengths, and is highly sensitive to the coherence length of the imaging light source. To our knowledge this is the first demonstration of in vivo optical imaging of the fast physiological processes that accompany phototransduction in individual photoreceptors.

Jonnal, Ravi S.; Rha, Jungtae; Zhang, Yan; Cense, Barry; Gao, Weihua; Miller, Donald T.

2009-01-01

92

In vivo functional imaging of human cone photoreceptors  

PubMed Central

We evaluate a novel non-invasive optical technique for observing fast physiological processes, in particular phototransduction, in single photoreceptor cells in the living human eye. The method takes advantage of the interference of multiple reflections within the outer segments (OS) of cones. This self-interference phenomenon is highly sensitive to phase changes such as those caused by variations in refractive index and scatter within the photoreceptor cell. A high-speed (192 Hz) flood-illumination retina camera equipped with adaptive optics (AO) is used to observe individual photoreceptors, and to monitor changes in their reflectance in response to visible stimuli (“scintillation”). AO and high frame rates are necessary for resolving individual cones and their fast temporal dynamics, respectively. Scintillation initiates within 5 to 10 ms after the onset of the stimulus flash, lasts 300 to 400 ms, is observed at visible and near-infrared (NIR) wavelengths, and is highly sensitive to the coherence length of the imaging light source. To our knowledge this is the first demonstration of in vivo optical imaging of the fast physiological processes that accompany phototransduction in individual photoreceptors.

Jonnal, Ravi S.; Rha, Jungtae; Zhang, Yan; Cense, Barry; Gao, Weihua; Miller, Donald T.

2008-01-01

93

In vivo and in vitro HeNe laser effects on phagocyte functions  

Microsoft Academic Search

The goal of this work was to evaluate the effect of helium-neon (HeNe) laser irradiation on immunocompetent cells. We used the in vivo skin window method and in vitro granulocyte function tests. The study of cellular migration showed a marked decrease in vitro and in vivo in a dose-independent manner. Superoxide release was not modified by laser irradiation. The granulocyte's

G. Ricevuti; A. Mazzone; C. Monaia; P. Fratino; R. Degiulio; R. Dell'acqua; G. Leonardi; A. Jucci; S. Sacchi

1989-01-01

94

Noninvasive laser-induced photoacoustic tomography for structural and functional in vivo imaging of the brain  

Microsoft Academic Search

Imaging techniques based on optical contrast analysis can be used to visualize dynamic and functional properties of the nervous system via optical signals resulting from changes in blood volume, oxygen consumption and cellular swelling associated with brain physiology and pathology. Here we report in vivo noninvasive transdermal and transcranial imaging of the structure and function of rat brains by means

Xueding Wang; Yongjiang Pang; Geng Ku; Xueyi Xie; George Stoica; Lihong V Wang

2003-01-01

95

The effects of flavanol-rich cocoa and aspirin on ex vivo platelet function  

Microsoft Academic Search

Background: Flavanols modulate platelet function in vitro, but less is known of their in vivo effects and how they compare to pharmacological platelet inhibitors. We investigated the effect of a flavanol-rich cocoa beverage (897 mg\\/ml) in combination with and in comparison to aspirin on platelet function and activation in healthy subjects. Methods and results: On separate test days in a

Debra A Pearson; Teresa G Paglieroni; Dietrich Rein; Ted Wun; Derek D Schramm; Janice F Wang; Roberta R Holt; Robert Gosselin; Harold H Schmitz; Carl L Keen

2002-01-01

96

Evaluation of effector cell fate and function by in vivo bioluminescence imaging  

Microsoft Academic Search

The effector functions of immune cells have typically been examined using assays that require sampling of tissues or cells to reveal specific aspects of an immune response (e.g., antigen-specificity, cytokine expression or killing of target cells). The outcome of an immune response in vivo, however, is not solely determined by a single effector function of a specific cell population, but

Matthias Edinger; Petra Hoffmann; Christopher H Contag; Robert S Negrin

2003-01-01

97

Thyroid hormone stimulates progesterone release from human luteal cells by generating a proteinaceous factor  

Microsoft Academic Search

Blood samples collected from 29 women (aged between 19 and 35 years) during the luteal phase of the menstrual cycle (between days 18 and 23 of the cycle) showed that deficiency in thyroid hormone level is related to a decrease in progesterone (P4) secretion. To observe the eVect of thyroid hormone on human ovarian luteal cells, 3,5,3*-tri- iodothyronine (T3; 125

M Datta; P Roy; J Banerjee; S Bhattacharya

1998-01-01

98

The luteal phase after GnRH agonist triggering of ovulation: present and future perspectives  

Microsoft Academic Search

In stimulated IVF\\/intracytoplasmic sperm injection (ICSI) cycles, the luteal phase is disrupted, necessitating luteal-phase supplementation. The most plausible reason behind this is the ovarian multifollicular development obtained after ovarian stimulation, resulting in supraphysiological steroid concentrations and consecutive inhibition of LH secretion by the pituitary via negative feedback at the level of the hypothalamic–pituitary axis. With the introduction of the gonadotrophin-releasing

Peter Humaidan; E. G. Papanikolaou; D. Kyrou; B. Alsbjerg; N. P. Polyzos; P. Devroey; Human M. Fatemi

99

Luteal phase characteristics following GnRH antagonist or agonist treatment – a comparative study  

Microsoft Academic Search

Due to inherent differences between gonadotrophin-releasing hormone (GnRH) antagonists and agonists, their late effect on ovarian steroidal production during the luteal phase of IVF cycles may differ. The aim of this study was to characterize and compare the luteal phase hormonal profile after the use of GnRH antagonists or agonists in ovarian stimulation protocols for IVF, in non-conception cycles, to

Shevach Friedler; Sarit Gilboa; Morey Schachter; Arieh Raziel; Devorah Strassburger; Raphael Ron El

2006-01-01

100

Assessment of progesterone profiles and postpartum onset of luteal activity in spring calving Hereford beef suckler cattle  

PubMed Central

Background Reproduction is the single greatest factor limiting beef cattle production. Previous research on beef suckler luteal activity has largely focused on the mechanisms, and duration, of postpartum anoestrus. However, the temporal pattern of luteal activity after resumption of post-partum ovarian activity, and the impact of pattern type on days open (DO) in purebred beef suckler cows, are unknown. Methods Progesterone concentration was measured in milk samples taken thrice weekly from 120 lactations, in 87 animals, on 3 farms, over two years. Onset of luteal activity (OLA) was defined as the first day milk progesterone concentration exceeded 3 ng/ml for two successive measurements, or exceeded 5 ng/ml once. It was defined as delayed if it occurred more than 61 days postpartum. A short initial luteal phase consisted of progesterone concentrations which exceeded 3 ng/ml for fewer than 4 sequential measurements. Temporal progesterone patterns were classified as: 1) Normal cyclicity; 2) Cessation of luteal activity; 3) Prolonged luteal activity; 4) Erratic phase: failure to conform to 1, 2 or 3. Data concerning parity, previous calving interval, breeding values, calf birth and 200-d weight were obtained from the Norwegian Beef Cattle Recording System database. Results The mean (SD) OLA was 41 d (20). Parity and calf birth weight were inversely correlated with OLA. Delayed OLA occurred in 14.4% of lactations. A short first luteal phase occurred in 61.5% of lactations, but this was unrelated to irregular luteal phase occurrence, pregnancy or DO. Irregular luteal phases occurred in 22% of lactations. The irregularities were: prolonged luteal phase (11%); cessation of luteal activity (5%); erratic luteal activity (6%). Early OLA was associated with prolonged luteal phases. DO was positively correlated with irregular luteal phases and negatively correlated with calf 200-d weight. Conclusions This study demonstrates that irregular luteal phases negatively affect reproductive performance in purebred beef suckler cattle. A moderate incidence of irregular luteal phases was seen in the study population. Whilst a positive relationship was seen between OLA and DO, unfavourable associations between early OLA and incidence of irregular luteal phases should be considered when developing breeding programmes.

2010-01-01

101

In vivo functional tests for assessing immunotoxicity in birds.  

PubMed

Various methods have been adapted for assessing the effects of environmental contaminants on the structure and function of the immune system in wild and captive birds. This chapter describes two integrative functional assays that have been adapted to a variety of avian species and have proven to be sensitive biomarkers for immunotoxicological effects. The phytohemagglutinin (PHA) skin test measures T cell-mediated immunity. PHA is injected intra- or sub-dermally into the wing web of the elbow joint (or interdigitary skin or wattle). The PHA stimulates T lymphocytes to release cytokines that cause an inflammatory influx of leukocytes and fluid. The thickness of the wing web is measured before and 24 h after injection. A stimulation index, which reflects T cell function, is calculated as the increase in skin thickness caused by the PHA minus the increase caused by an injection of phosphate buffered saline (PBS) in the other wing web. In addition to its sensitivity to contaminants, ecological studies have shown that the PHA skin response is positively associated with rates of survival and colonization of new areas (i.e., ability to found new local populations) in wild birds.The sheep red blood cell (SRBC) hemagglutination assay measures the antibody response to immunization with SRBC antigens, integrating the functions of B lymphocytes, helper T lymphocytes, and macrophages. A SRBC suspension is injected i.v., and a blood sample is collected approximately 6 days later. Plasma (or serum) from the blood sample is serially diluted in a microtiter plate, and SRBCs are added. The magnitude of the antibody response is defined as the titer - the highest dilution of plasma in which the concentration of antibody is sufficient to agglutinate the SRBCs. Both IgM and IgG titers can be measured. This avian test is very similar in principle to the anti-SRBC ELISA and splenic plaque forming assays used for immunotoxicological testing in rodents. However, this avian hemagglutination assay does not require a species-specific secondary antibody (as does the ELISA), and this minimally invasive, nonlethal procedure is amenable to studies of protected species, as opposed to the splenic assay. The PHA and SRBC assays have been employed successfully in both the laboratory and field. In ecological studies birds must be recaptured 24 h or 6 days after the initial injections, limiting their use in some species. However, their sensitivity to a variety of contaminants and their ease of adaptability to a variety of species have made the PHA and SRBC tests some of the most commonly used assays for screening and monitoring immunotoxicity in birds. PMID:19967526

Grasman, Keith A

2010-01-01

102

Glycerol accelerates recovery of barrier function in vivo.  

PubMed

Two studies were performed to evaluate the influence of glycerol on the recovery of damaged stratum corneum barrier function. Measurements of transepidermal water loss and capacitance were conducted in a 3-day follow-up after tape stripping (study 1) and a 7-day follow-up after a barrier damage due to a repeated washing with sodium lauryl sulphate. In study 1 a faster barrier repair (transepidermal water loss) was monitored in glycerol-treated sites. Significant differences between glycerol open vs. untreated and glycerol occluded vs. untreated were observed at day 3. Stratum corneum hydration showed significantly higher values in the sites treated with glycerol+occlusion, compared with all other sites. In study 2 a faster barrier repair was seen in glycerol-treated sites, with significant differences against untreated and base-treated sites 7 days after the end of the treatment. Stratum corneum hydration showed highest values in the glycerol treated sites after 3 days of treatment. Glycerol creates a stimulus for barrier repair and improves the stratum corneum hydration; stratum corneum hydration is not strictly related to barrier homeostasis and can be optimized by different mechanisms and pathways. The observed effects were based on the modulation of barrier repair and were not biased by the humectant effect of glycerol. As the glycerol-induced recovery of barrier function and stratum corneum hydration were observed even 7 days after the end of treatment, glycerol can be regarded as a barrier stabilizing and moisturizing compound. PMID:10598752

Fluhr, J W; Gloor, M; Lehmann, L; Lazzerini, S; Distante, F; Berardesca, E

1999-11-01

103

Effect of Processing and Storage on RBC function in vivo  

PubMed Central

Red Blood Cell (RBC) transfusion is indicated to improve oxygen delivery to tissue, and for no other purpose. We have come to appreciate that donor RBCs are fundamentally altered during processing and storage, in a fashion that both impairs oxygen transport efficacy and introduces additional risk by perturbing both immune and coagulation systems. The protean biophysical and physiologic changes in RBC function arising from storage are termed the ‘storage lesion’; many have been understood for some time; for example, we know that the oxygen affinity of stored blood rises during the storage period1 and that intracellular allosteric regulators, notably 2,3-bisphosphoglyceric acid (DPG) and ATP, are depleted during storage. Our appreciation of other storage lesion features has emerged with improved understanding of coagulation, immune and vascular signaling systems. Herein we review key features of the ‘storage lesion’. Additionally, we call particular attention to the newly appreciated role of RBCs in regulating linkage between regional blood flow and regional O2 consumption by regulating the bioavailability of key vasoactive mediators in plasma, as well as discuss how processing and storage disturbs this key signaling function and impairs transfusion efficacy.

Doctor, Allan; Spinella, Phil

2012-01-01

104

Expression of adrenomedullin in human ovaries, ovarian sex cord-stromal tumors and cultured granulosa-luteal cells.  

PubMed

The aim of the present study was to characterise the expression pattern of the multifunctional vasoactive peptide adrenomedullin (ADM) in human ovarian tumors, and to find hormonal regulators of ADM expression in human ovaries. The expression of ADM messenger RNA (mRNA) was higher in granulosa cell tumors than in fibrothecomas and normal ovaries, as analysed by Northern blots. In normal ovaries, ADM immunoreactivity was localised in both granulosa and thecal cells. Eight of the 90 granulosa cell tumors (9%) showed moderate and 53 (59%) weak ADM immunoreactivity, whereas 27% (11/41) of the fibrothecomas displayed weak ADM staining. FSH, protein kinase A activator (Bu)(2)cAMP, prostaglandin E(2) (PGE(2)), activin A and the broad protein kinase regulator staurosporine decreased ADM mRNA accumulation in cultured granulosa-luteal cells time- and dose-dependently. FSH, (Bu)(2)cAMP and PGE(2) increased progesterone secretion and the accumulation of the steroidogenic acute regulatory protein mRNA in these cells. In conclusion, ADM is expressed in normal human ovaries and sex cord-stromal tumors, particularly in those of granulosa cell origin. FSH, PGE(2,) (Bu)(2)cAMP and activin A suppress ADM gene expression in granulosa-luteal cells. Expression of ADM in human ovaries and its hormonal regulation in granulosa cells suggests a paracrine role for ADM in ovarian function. PMID:19253104

Liu, Jianqi; Bützow, Ralf; Hydén-Granskog, Christel; Voutilainen, Raimo

2009-02-01

105

In vivo imaging of molecular targets and their function in endocrinology  

PubMed Central

Imaging is one of the fastest growing fields of study. New technologies and multimodal approaches are increasing the application of imaging to determine molecular targets and functional processes in vivo. The identification of a specific target, transporter, or biological process using imaging has introduced major breakthroughs to the field of endocrinology primarily utilizing computed tomography, magnetic resonance imaging, ultrasonography, positron emission tomography, single-photon emission computed tomography, and optical imaging. This review provides a general background to the specific developments in imaging that pertains to in vivo function and target identification in endocrine-based diseases.

Burdette, Joanna E

2010-01-01

106

The effect of progesterone replacement on gene expression in the corpus luteum during induced regression and late luteal phase in the bonnet monkey (Macaca radiata)  

PubMed Central

Background In higher primates, although LH/CG play a critical role in the control of corpus luteum (CL) function, the direct effects of progesterone (P4) in the maintenance of CL structure and function are unclear. Several experiments were conducted in the bonnet monkey to examine direct effects of P4 on gene expression changes in the CL, during induced luteolysis and the late luteal phase of natural cycles. Methods To identify differentially expressed genes encoding PR, PR binding factors, cofactors and PR downstream signaling target genes, the genome-wide analysis data generated in CL of monkeys after LH/P4 depletion and LH replacement were mined and validated by real-time RT-PCR analysis. Initially, expression of these P4 related genes were determined in CL during different stages of luteal phase. The recently reported model system of induced luteolysis, yet capable of responsive to tropic support, afforded an ideal situation to examine direct effects of P4 on structure and function of CL. For this purpose, P4 was infused via ALZET pumps into monkeys 24 h after LH/P4 depletion to maintain mid luteal phase circulating P4 concentration (P4 replacement). In another experiment, exogenous P4 was supplemented during late luteal phase to mimic early pregnancy. Results Based on the published microarray data, 45 genes were identified to be commonly regulated by LH and P4. From these 19 genes belonging to PR signaling were selected to determine their expression in LH/P4 depletion and P4 replacement experiments. These 19 genes when analyzed revealed 8 genes to be directly responsive to P4, whereas the other genes to be regulated by both LH and P4. Progesterone supplementation for 24 h during the late luteal phase also showed changes in expression of 17 out of 19 genes examined. Conclusion These results taken together suggest that P4 regulates, directly or indirectly, expression of a number of genes involved in the CL structure and function.

2011-01-01

107

Structural and Functional Dissection of the Abp1 ADFH Actin-binding Domain Reveals Versatile In Vivo Adapter Functions  

Microsoft Academic Search

Abp1 is a multidomain protein that regulates the Arp2\\/3 complex and links proteins involved in endocytosis to the actin cytoskeleton. All of the proposed cellular functions of Abp1 involve actin filament binding, yet the actin binding site(s) on Abp1 have not been identified, nor has the importance of actin binding for Abp1 localization and function in vivo been tested. Here,

Omar Quintero-Monzon; Avital A. Rodal; Boris Strokopytov; Steven C. Almo; Bruce L. Goode

2005-01-01

108

Staged decline of neuronal function in vivo in an animal model of Alzheimer's disease  

PubMed Central

The accumulation of amyloid-? in the brain is an essential feature of Alzheimer's disease. However, the impact of amyloid-?-accumulation on neuronal dysfunction on the single cell level in vivo is poorly understood. Here we investigate the progression of amyloid-? load in relation to neuronal dysfunction in the visual system of the APP23×PS45 mouse model of Alzheimer's disease. Using in vivo two-photon calcium imaging in the visual cortex, we demonstrate that a progressive deterioration of neuronal tuning for the orientation of visual stimuli occurs in parallel with the age-dependent increase of the amyloid-? load. Importantly, we find this deterioration only in neurons that are hyperactive during spontaneous activity. This impairment of visual cortical circuit function also correlates with pronounced deficits in visual-pattern discrimination. Together, our results identify distinct stages of decline in sensory cortical performance in vivo as a function of the increased amyloid-?-load.

Grienberger, Christine; Rochefort, Nathalie L.; Adelsberger, Helmuth; Henning, Horst A.; Hill, Daniel N.; Reichwald, Julia; Staufenbiel, Matthias; Konnerth, Arthur

2012-01-01

109

Effect of progesterone and/or estradiol treatments prior to induction of ovulation on subsequent luteal lifespan in anestrous Nelore cows.  

PubMed

Three experiments evaluated effects of estradiol (E(2)) and/or progesterone (P(4)) prior to induction of ovulation with GnRH on subsequent luteal lifespan in anestrous Nelore cows. In Experiment 1, cows (25-65 days post-partum [DPP]; n=114) were assigned randomly to receive a 6-day treatment with an intravaginal P(4) device (CIDR) and/or 1mg i.m. injection of 17beta-E(2) (4 groups; 2x2 factorial design) prior to ovulation. Blood samples were collected on days 0, 5, 7, 9, 12, 15 and 19 for evaluation of luteal function. Pre-treatment with P(4) reduced occurrence of premature luteolysis (PL; 79.2% in non-treated vs. 13.5% in treated cows; P<0.01), but there was no effect of treatment with 17beta-E(2) on percentage of PL. In Experiment 2, cows (30-40 DPP; n=35) were assigned randomly to receive either 0.5mL i.m. injection of cottonseed oil (placebo) or 1mg i.m. injection of E(2) cypionate. Blood samples were collected on days 0, 5, 9 and 15 for evaluation of luteal function. Incidence of PL (83.0% in Control Group vs. 75.0% in ECP Group; P>0.1) and mean serum P(4) did not differ between treatment groups. In Experiment 3, cows (30-60 DPP; n=109) were randomly assigned to receive either a 6-day (6-d Group) or a 3-day (3-d Group) treatment with CIDR. Blood samples were collected on days 0, 5, 7 and 9 for luteal function evaluation. Incidence of PL (5.5% in 6-day vs. 5.5% in 3-day groups; P>0.1) and mean serum P(4) did not differ between treatment groups. In conclusion, both 3- and 6-day treatments with P(4) prior to induction of ovulation in anestrous Nelore cows increased percentage of normal luteal lifespan, while administration of 1mg of 17beta-E(2) or E(2) cypionate failed to prevent occurrence of PL. PMID:18468816

Sá Filho, Ocilon Gomes; Thatcher, William Watters; Vasconcelos, José Luiz Moraes

2008-04-11

110

A chemical-genetic approach to study G protein regulation of ? cell function in vivo  

PubMed Central

Impaired functioning of pancreatic ? cells is a key hallmark of type 2 diabetes. ? cell function is modulated by the actions of different classes of heterotrimeric G proteins. The functional consequences of activating specific ? cell G protein signaling pathways in vivo are not well understood at present, primarily due to the fact that ? cell G protein-coupled receptors (GPCRs) are also expressed by many other tissues. To circumvent these difficulties, we developed a chemical-genetic approach that allows for the conditional and selective activation of specific ? cell G proteins in intact animals. Specifically, we created two lines of transgenic mice each of which expressed a specific designer GPCR in ? cells only. Importantly, the two designer receptors differed in their G protein-coupling properties (Gq/11 versus Gs). They were unable to bind endogenous ligand(s), but could be efficiently activated by an otherwise pharmacologically inert compound (clozapine-N-oxide), leading to the conditional activation of either ? cell Gq/11 or Gs G proteins. Here we report the findings that conditional and selective activation of ? cell Gq/11 signaling in vivo leads to striking increases in both first- and second-phase insulin release, greatly improved glucose tolerance in obese, insulin-resistant mice, and elevated ? cell mass, associated with pathway-specific alterations in islet gene expression levels. Selective stimulation of ? cell Gs triggered qualitatively similar in vivo metabolic effects. Thus, this developed chemical-genetic strategy represents a powerful approach to study G protein regulation of ? cell function in vivo.

Guettier, Jean-Marc; Gautam, Dinesh; Scarselli, Marco; de Azua, Inigo Ruiz; Li, Jian Hua; Rosemond, Erica; Ma, Xiaochao; Gonzalez, Frank J.; Armbruster, Blaine N.; Lu, Huiyan; Roth, Bryan L.; Wess, Jurgen

2009-01-01

111

In vivo imaging of neutrotransmitter functions in brain, heart and tumors. Proceedings  

SciTech Connect

This volume contains the proceedings of a symposium entitled ``In Vivo Imaging of Neurotransmitter Function in Brain, Heart, and Tumors`` held August 24--25, 1990 in Montreal Canada. The six individual papers contained herein are separately abstracted and indexed for the database.

Kuhl, D.E. [ed.

1991-12-31

112

In vivo imaging of neutrotransmitter functions in brain, heart and tumors  

SciTech Connect

This volume contains the proceedings of a symposium entitled In Vivo Imaging of Neurotransmitter Function in Brain, Heart, and Tumors'' held August 24--25, 1990 in Montreal Canada. The six individual papers contained herein are separately abstracted and indexed for the database.

Kuhl, D.E. (ed.)

1991-01-01

113

A Sensitive in vivo Platelet Function Test in Rats Based on Intravenously Injected Collagenase  

Microsoft Academic Search

The transient decrease of the platelet concentration in the flowing blood after intravenous injection of collagenase was used as a measure for the effectiveness of the platelet-vessel wall interactions in rats. The decrease of the concentration in circulating platelets was regarded as an expression of the in vivo platelet function. The influence of acetylsalicylic acid, imidazole, indomethacin, ketanserin, RA 233,

K.-P. Völkl

1989-01-01

114

Functional role of TRPC proteins in vivo: lessons from TRPC-deficient mouse models  

Microsoft Academic Search

In order to elucidate the functional role of TRPC genes, in vivo, the targeted inactivation of these genes in mice is an invaluable technique. In this review, we summarize the currently available results on the phenotype of TRPC-deficient mouse lines. The analysis of mice with targeted deletion in three TRPC genes demonstrates that these proteins represent essential constituents of agonist-activated

M. Freichel; R. Vennekens; J. Olausson; M. Hoffmann; C. Müller; S. Stolz; J. Scheunemann; P. Weißgerber; V. Flockerzi

2004-01-01

115

Ageing-related changes in the in vivo function of rat liver macroautophagy and proteolysis  

Microsoft Academic Search

Autophagy is a universal, highly regulated mechanism responsible for the degradation of long-lived proteins, cytomembranes and organelles during fasting and may be the cell repair mechanism that mediates the anti-ageing effects of calorie restriction (Bergamini and Gori, 1995). The function of autophagy was studied in vivo on male Sprague Dawley rats fed ad libitum or 40% food restricted. Autophagy was

Alessandra Del Roso; Simona Vittorini; Gabriella Cavallini; Alessio Donati; Zina Gori; Matilde Masini; Maria Pollera; Ettore Bergamini

2003-01-01

116

Experimental models to study development and function of the human immune system in vivo  

Microsoft Academic Search

The study of development and function of the immune system in vivo has made intensive use ofanimal models, but performing such work in humans is difflcultfor experimental, practical and ethical reasons. Conftonted with this scientific challenge, several pioneering groups have developed in the late 1980s mouse models ofhuman immune system development. Although these experimental approaches were proven successful and useful

Nicolas Legrand; Kees Weijer; Hergen Spits

2006-01-01

117

Recent developments in the understanding of astrocyte function in the cerebellum in vivo.  

PubMed

Several studies have contributed to our understanding of astrocytes, especially Bergmann glia, in the cerebellum; but, until recently, none has looked at their function in vivo. Multicell bolus loading of fluorescent calcium indicators in combination with the astrocytic marker SR101 has allowed imaging of up to hundreds of astrocytes at once in the intact cerebellum. In addition, the selective targeting of astrocytes with fluorescent calcium indicator proteins has enabled the study of their function in vivo without the confounding effects of other neuropil signals and with a resolution that surpasses multicell bolus loading and SR101 staining. The two astrocyte types of the cerebellar cortex, Bergmann glia, and velate protoplasmic astrocytes display a diverse signaling repertoire in vivo, which ranges from localized calcium elevations in subcellular processes to waves, triggered by the release of purines and mediated by purinergic receptors that span multiple processes and can involve tens of astrocytes. During locomotor behavior, even larger numbers of astrocytes display calcium increases that are driven by neuronal activity and correlate with global changes in blood flow. In this review, we give an overview of our current understanding of the function of Bergmann glia and velate protoplasmic astrocytes and the promise of the tools used to study their calcium dynamics and function in vivo. PMID:19904577

Hoogland, Tycho M; Kuhn, Bernd

2010-09-01

118

Cutaneous respirometry by dynamic measurement of mitochondrial oxygen tension for monitoring mitochondrial function in vivo.  

PubMed

Progress in diagnosis and treatment of mitochondrial dysfunction in chronic and acute disease could greatly benefit from techniques for monitoring of mitochondrial function in vivo. In this study we demonstrate the feasibility of in vivo respirometry in skin. Mitochondrial oxygen measurements by means of oxygen-dependent delayed fluorescence of protoporphyrin IX are shown to provide a robust basis for measurement of local oxygen disappearance rate (ODR). The fundamental principles behind the technology are described, together with an analysis method for retrievel of respirometry data. The feasibility and reproducibility of this clinically useful approach are demonstrated in a series of rats. PMID:23063685

Harms, Floor A; Voorbeijtel, Wilhelmina J; Bodmer, Sander I A; Raat, Nicolaas J H; Mik, Egbert G

2012-10-12

119

Inhibition of progesterone secretion by oestradiol administered in the luteal phase of assisted conception cycles.  

PubMed

A prospective randomised study was done to assess the effect of supplemental oestradiol in addition to progesterone on the luteal steroid profiles and pregnancy outcome in stimulated cycles with and without pituitary down regulation. Women undergoing stimulated cycle IVF with GnRH-a and FSH (Group A, n = 63) or stimulated intrauterine insemination using CC and FSH (Group B, n = 55) were studied. These subjects were randomly allocated to receive either 400 mg daily of vaginally administrated Cyclogest (progesterone) alone or in combination with 2 mg daily of oral Oestradiol Valerate (E2V) during the luteal phase. Significant lower concentrations of plasma progesterone were observed in those subjects supplemented with both E2V and progesterone compared to those in whom progesterone only was given during the luteal phase (P < 0.05). Exogenous E2V had a minimal impact on plasma oestradiol concentrations and did not disguise the characterised mid luteal decline in oestradiol secretion. The suppressive effect of E2V on plasma progesterone was lost if implantation occurred normally because any small change in steroid concentrations was reversed by the rapidly increasing concentrations of HCG. Similar pregnancy rates were observed among subjects supplemented with or without oestradiol. The addition of oestradiol to the luteal supplement suppresses endogenous corpus luteum progesterone secretion irrespective of the type of assisted conception cycle and that its use is unlikely to be beneficial to the process of implantation. PMID:14569738

Tay, P Y; Lenton, E A

2003-06-01

120

In-vivo plasma-mediated ablation as a function of laser pulse width  

NASA Astrophysics Data System (ADS)

We evaluated in vivo wound healing responses to plasma- mediated ablation in skin as a function of laser pulsewidth and energy. Experiments utilized a regeneratively amplified Ti:Sapphire laser operating at 800 nm with pulsewidths varied from 7 ns to 100 fs. Skin incisions were created in mice by tightly focusing the laser beam on the tissue surface. Incisions of equal depth were compared at time points ranging from 6 hours to 3 weeks using standard histologic methods. Incision depth was proportional to pulse energy at each pulsewidth. Fluence threshold dependence on laser pulsewidth agreed with those predicted by ex vivo testing. Histologic analysis revealed minimal adjacent tissue damage at pulsewidths less than a few picoseconds and energies near the fluence threshold. Longer pulsewidths and higher fluence levels were associated with more significant collateral effects. These in vivo results suggest collateral tissue damage and secondary effects may be minimized by controlling laser pulsewidth and energy.

Liu, Xinbing; Tien, An Xien; Juhasz, Tibor; Irish, Barbara; Elner, Victor; Kurtz, Ron M.

1997-06-01

121

In Vivo Function of Tryptophans in the Arabidopsis UV-B Photoreceptor UVR8[W  

PubMed Central

Arabidopsis thaliana UV RESISTANCE LOCUS8 (UVR8) is a photoreceptor specifically for UV-B light that initiates photomorphogenic responses in plants. UV-B exposure causes rapid conversion of UVR8 from dimer to monomer, accumulation in the nucleus, and interaction with CONSTITUTIVELY PHOTOMORPHOGENIC1 (COP1), which functions with UVR8 in UV-B responses. Studies in yeast and with purified UVR8 implicate several tryptophan amino acids in UV-B photoreception. However, their roles in UV-B responses in plants, and the functional significance of all 14 UVR8 tryptophans, are not known. Here we report the functions of the UVR8 tryptophans in vivo. Three tryptophans in the ?-propeller core are important in maintaining structural stability and function of UVR8. However, mutation of three other core tryptophans and four at the dimeric interface has no apparent effect on function in vivo. Mutation of three tryptophans implicated in UV-B photoreception, W233, W285, and W337, impairs photomorphogenic responses to different extents. W285 is essential for UVR8 function in plants, whereas W233 is important but not essential for function, and W337 has a lesser role. Ala mutants of these tryptophans appear monomeric and constitutively bind COP1 in plants, but their responses indicate that monomer formation and COP1 binding are not sufficient for UVR8 function.

O'Hara, Andrew; Jenkins, Gareth I.

2012-01-01

122

Techniques for the in vivo assessment of cardio-renal function in zebrafish (Danio rerio) larvae  

PubMed Central

Zebrafish, a well-established vertebrate model, offer unique advantages for assessing renal function and physiology. Assays determining renal glomerular function based on cardiovascular erythrocyte flow and reduction of injected FITC-inulin were developed, each validated using the nephrotoxin gentamicin. Bland–Atlman analysis showed a strong association between measurements of the rate of inulin excretion and that of fluorescent reduction from the arterial vasculature. Reduced renal clearance of inulin, resulting from gentamicin or NaCl loading, was concurrent with reduced erythrocyte velocity, and yolk sac and pericardium oedema. These techniques, assessing pronephric function, highlight the potential for in vivo physiological study in this genetically tractable model.

Rider, Sebastien A; Tucker, Carl S; del-Pozo, Jorge; Rose, Kirsten N; MacRae, Calum A; Bailey, Matthew A; Mullins, John J

2012-01-01

123

Functionalized gold nanoparticles: a detailed in vivo multimodal microscopic brain distribution study  

NASA Astrophysics Data System (ADS)

In the present study, the in vivo distribution of polyelectrolyte multilayer coated gold nanoparticles is shown, starting from the living animal down to cellular level. The coating was designed with functional moieties to serve as a potential nano drug for prion disease. With near infrared time-domain imaging we followed the biodistribution in mice up to 7 days after intravenous injection of the nanoparticles. The peak concentration in the head of mice was detected between 19 and 24 h. The precise particle distribution in the brain was studied ex vivo by X-ray microtomography, confocal laser and fluorescence microscopy. We found that the particles mainly accumulate in the hippocampus, thalamus, hypothalamus, and the cerebral cortex.In the present study, the in vivo distribution of polyelectrolyte multilayer coated gold nanoparticles is shown, starting from the living animal down to cellular level. The coating was designed with functional moieties to serve as a potential nano drug for prion disease. With near infrared time-domain imaging we followed the biodistribution in mice up to 7 days after intravenous injection of the nanoparticles. The peak concentration in the head of mice was detected between 19 and 24 h. The precise particle distribution in the brain was studied ex vivo by X-ray microtomography, confocal laser and fluorescence microscopy. We found that the particles mainly accumulate in the hippocampus, thalamus, hypothalamus, and the cerebral cortex. Electronic supplementary information (ESI) available: Fig. S1-S6. See DOI: 10.1039/c0nr00345j

Sousa, Fernanda; Mandal, Subhra; Garrovo, Chiara; Astolfo, Alberto; Bonifacio, Alois; Latawiec, Diane; Menk, Ralf Hendrik; Arfelli, Fulvia; Huewel, Sabine; Legname, Giuseppe; Galla, Hans-Joachim; Krol, Silke

2010-12-01

124

Should luteal phase support be introduced in ovarian stimulation\\/IUI programmes? An evidence-based review  

Microsoft Academic Search

World-wide, intrauterine insemination (IUI) is still one of the most applied techniques to enhance the probability of conception in couples with longstanding subfertility. The outcome of this treatment option depends on many confounding factors. One of the confounding factors receiving little attention is the quality of the luteal phase. From IVF studies, it is known that ovarian stimulation causes luteal

BJ Cohlen

2009-01-01

125

Assessment of progesterone profiles and postpartum onset of luteal activity in spring calving Hereford beef suckler cattle  

Microsoft Academic Search

BACKGROUND: Reproduction is the single greatest factor limiting beef cattle production. Previous research on beef suckler luteal activity has largely focused on the mechanisms, and duration, of postpartum anoestrus. However, the temporal pattern of luteal activity after resumption of post-partum ovarian activity, and the impact of pattern type on days open (DO) in purebred beef suckler cows, are unknown. METHODS:

Adam D Martin; Marit L Lystad; Olav Reksen; Erik Ropstad; Andres Waldmann; Ola Nafstad; Knut Karlberg

2010-01-01

126

Impact of norgestomet supplementation during early luteal phase on subsequent luteal profiles and conception rate in buffalo: a preliminary study.  

PubMed

The current study was aimed to establish the impact of progesterone supplementation (norgestomet progestagen) between days 4 to 10 post-ovulation on subsequent luteal profile and conception rate in buffaloes. The 28 Murrah buffaloes of second to fourth parity, having normal reproductive organs, were estrus synchronized by double PGF(2?) protocol at 11 days apart. The buffaloes were inseminated during mid- to late estrus and thereafter repeated at 24 h interval. The buffaloes were randomly assigned into two groups: (1) control (no treatment, n = 14) and (2) treatment group (CRESTAR ear implant, n = 14). The CRESTAR ear implant (3 mg, norgestomet progestagen) was inserted subcutaneous between days 4 to 10 post-ovulation. The ovaries were scanned at estrus and thereafter on days 4, 10, 16, 21, and 40 post-ovulation to examine the preovulatory follicle (POF) and corpus luteum (CL) diameter. Each ultasonography was followed by blood sample collection for analysis of plasma progesterone concentrations following ovulation. The conception rate was similar (p > 0.05) between treated and control buffaloes. The pregnant buffalo of the control group had larger (p < 0.05) POF diameter than nonpregnant counterparts. The CL diameter was similar (p > 0.05) in both treated and untreated control as well as in their pregnant and nonpregnant buffaloes of the respective groups. The plasma progesterone concentrations were higher (p < 0.05) in the treatment group on the day 10 post-ovulation as compared to the control buffaloes. It is concluded that norgestomet supplementation had no impact on conception rate and CL diameter but enhances the plasma progesterone concentrations following treatment in buffaloes. PMID:22802094

Pandey, Anand Kumar; Dhaliwal, Gurcharan Singh; Ghuman, Sarvpreet Singh; Singh, Jagir; Kumar, Ajeet; Agarwal, Sudhir Kumar

2012-07-18

127

Bacterial ApbC Protein Has Two Biochemical Activities That Are Required for in Vivo Function*  

PubMed Central

The ApbC protein has been shown previously to bind and rapidly transfer iron-sulfur ([Fe-S]) clusters to an apoprotein (Boyd, J. M., Pierik, A. J., Netz, D. J., Lill, R., and Downs, D. M. (2008) Biochemistry 47, 8195–8202. This study utilized both in vivo and in vitro assays to examine the function of variant ApbC proteins. The in vivo assays assessed the ability of ApbC proteins to function in pathways with low and high demand for [Fe-S] cluster proteins. Variant ApbC proteins were purified and assayed for the ability to hydrolyze ATP, bind [Fe-S] cluster, and transfer [Fe-S] cluster. This study details the first kinetic analysis of ATP hydrolysis for a member of the ParA subfamily of “deviant” Walker A proteins. Moreover, this study details the first functional analysis of mutant variants of the ever expanding family of ApbC/Nbp35 [Fe-S] cluster biosynthetic proteins. The results herein show that ApbC protein needs ATPase activity and the ability to bind and rapidly transfer [Fe-S] clusters for in vivo function.

Boyd, Jeffrey M.; Sondelski, Jamie L.; Downs, Diana M.

2009-01-01

128

Failure to induce ovulation with clomiphene citrate and bromocriptine in luteal deficient women athletes.  

PubMed

This study was designed with a three-fold aim: to assess ovarian function of women athletes with menstrual irregularities (AMI); to evaluate the potentiality of clomiphene citrate and bromocriptine for the induction of ovulation in these women; and to show that ultrasound scanning offers a suitable technique for ovarian screening in healthy and high-performance athletes. Our small test group consisted of 11 women, mainly track athletes, with AMI. There was no significant difference in age at menarche (13.2 yrs +/- 0.2), percent of ideal body weight (92% +/- 4), or percent of body fat (12.3% +/- 2.8) among the subjects. Plasma estradiol values were low (mean: 22 pg/ml +/- 0.8), as those of plasma progesterone (2.85 ng/ml +/- 2.10), LH (5.6 mIU/ml +/- 0.8), and prolactin (10.89 ng/ml +/- 5.56). The mean distance run per week (35 km +/- 15) was relatively high considering the presence of 4 non-runners. All menstrual irregularities were attributed to exercise. A short luteal phase (7 days +/- 1.5 for a cycle with a mean duration of 25 days +/- 1.8) was found in all subjects. We failed to observe the presence of a corpus luteum in 9 out of 11 women. A two-month administration of clomiphene citrate (150 mg/d for 5 days) or bromocriptine (2.5 mg/d) did not succeed in provoking ovulation in any of these women. Ultrasonographic observations showed a continuously hypo-estrogenic endometrium with a consecutively developing and regressive follicle. Our data emphasize the difficulties inherent in the restoration of menstrual function in women athletes with AMI. In addition, the usefulness of ultrasound in screening ovarian function was confirmed. PMID:1889934

De Crée, C; Lewin, R; Ostyn, M

1991-06-01

129

Skeletal muscle oxidative function in vivo and ex vivo in athletes with marked hypertrophy from resistance training.  

PubMed

Oxidative function during exercise was evaluated in 11 young athletes with marked skeletal muscle hypertrophy induced by long-term resistance training (RTA; body mass 102.6 ± 7.3 kg, mean ± SD) and 11 controls (CTRL; body mass 77.8 ± 6.0 kg). Pulmonary O2 uptake (Vo2) and vastus lateralis muscle fractional O2 extraction (by near-infrared spectroscopy) were determined during an incremental cycle ergometer (CE) and one-leg knee-extension (KE) exercise. Mitochondrial respiration was evaluated ex vivo by high-resolution respirometry in permeabilized vastus lateralis fibers obtained by biopsy. Quadriceps femoris muscle cross-sectional area, volume (determined by magnetic resonance imaging), and strength were greater in RTA vs. CTRL (by ?40%, ?33%, and ?20%, respectively). Vo2peak during CE was higher in RTA vs. CTRL (4.05 ± 0.64 vs. 3.56 ± 0.30 l/min); no difference between groups was observed during KE. The O2 cost of CE exercise was not different between groups. When divided per muscle mass (for CE) or quadriceps muscle mass (for KE), Vo2 peak was lower (by 15-20%) in RTA vs. CTRL. Vastus lateralis fractional O2 extraction was lower in RTA vs. CTRL at all work rates, during both CE and KE. RTA had higher ADP-stimulated mitochondrial respiration (56.7 ± 23.7 pmol O2·s(-1)·mg(-1) ww) vs. CTRL (35.7 ± 10.2 pmol O2·s(-1)·mg(-1) ww) and a tighter coupling of oxidative phosphorylation. In RTA, the greater muscle mass and maximal force and the enhanced mitochondrial respiration seem to compensate for the hypertrophy-induced impaired peripheral O2 diffusion. The net results are an enhanced whole body oxidative function at peak exercise and unchanged efficiency and O2 cost at submaximal exercise, despite a much greater body mass. PMID:23519233

Salvadego, Desy; Domenis, Rossana; Lazzer, Stefano; Porcelli, Simone; Rittweger, Jörn; Rizzo, Giovanna; Mavelli, Irene; Simunic, Bostjan; Pisot, Rado; Grassi, Bruno

2013-03-21

130

Functional Characterization of Antibodies Neutralizing Soluble Factors In Vitro and In Vivo  

Microsoft Academic Search

\\u000a Functional characterization of antibodies that inhibit soluble cytokines or chemokines requires robust, sensitive in vitro\\u000a and in vivo bioassays. Testing an antibody in vitro requires consideration of antigen source, integrity, and concentration,\\u000a as well as the magnitude of the biologic response and assay interference by components in the antibody test sample. This chapter\\u000a describes several exemplary in vitro bioassays, including

Geertruida M. Veldman; Zehra Kaymakcalan; Renee Miller; Leena Kalghatgi; Jochen G. Salfeld

131

In vivo migration and function of transferred HIV1-specific cytotoxic T cells  

Microsoft Academic Search

The persistence of HIV replication in infected individuals may reflect an inadequate host HIV-specific CD8+ cytotoxic T lymphocyte (CTL) response. The functional activity of HIV-specific CTLs and the ability of these effector cells to migrate in vivo to sites of infection was directly assessed by expanding autologous HIV-1 Gag-specific CD8+ CTL clones in vitro and adoptively transferring these CTLs to

Scott J. Brodie; Deborah A. Lewinsohn; Bruce K. Patterson; Daniel Jiyamapa; John Krieger; Lawrence Corey; Philip D. Greenberg; Stanley R. Riddell

1999-01-01

132

In Vivo Functional Assay of a Recombinant Aquaporin in Pichia pastoris  

Microsoft Academic Search

The water channel protein PvTIP3;1 (-TIP) is a member of the major intrinsic protein (MIP) membrane channel family. We overexpressed this eukaryotic aquaporin in the methylotrophic yeast Pichia pastoris, and immunogold labeling of cellular cryosections showed that the protein accumulated in the plasma membrane, as well as vacuolar and other intracellular membranes. We then developed an in vivo functional assay

Mark J. Daniels; Malcolm R. Wood; Mark Yeager

2006-01-01

133

In vivo studies of development of the main functional systems in the heteronemertean pilidium larva  

Microsoft Academic Search

There is performed in vivo morphological study of the White Sea heteronemertines belonging to the type of Pilidium pyramidale (conussoidale). Based on the layer-by-layer microshooting with subsequent computer processing, development of the pilidium digestive, nervous,\\u000a and muscle systems is described from the stage following at once the gastrula till the premetamorphosis larva. Peculiarities\\u000a of structural organization of the main functional

O. V. Zaitseva; L. P. Flyachinskaya

2010-01-01

134

Atypical Membrane Topology and Heteromeric Function of Drosophila Odorant Receptors In Vivo  

Microsoft Academic Search

Drosophila olfactory sensory neurons (OSNs) each express two odorant receptors (ORs): a divergent member of the OR family and the highly conserved, broadly expressed receptor OR83b. OR83b is essential for olfaction in vivo and enhances OR function in vitro, but the molecular mechanism by which it acts is unknown. Here we demonstrate that OR83b heterodimerizes with conventional ORs early in

Richard Benton; Silke Sachse; Stephen W. Michnick; Leslie B. Vosshall

2006-01-01

135

Recent Developments in the Understanding of Astrocyte Function in the Cerebellum In Vivo  

Microsoft Academic Search

Several studies have contributed to our understanding of astrocytes, especially Bergmann glia, in the cerebellum; but, until\\u000a recently, none has looked at their function in vivo. Multicell bolus loading of fluorescent calcium indicators in combination\\u000a with the astrocytic marker SR101 has allowed imaging of up to hundreds of astrocytes at once in the intact cerebellum. In\\u000a addition, the selective targeting

Tycho M. Hoogland; Bernd Kuhn

2010-01-01

136

In vivo Testing of Functional Properties of Three Selected Probiotic Strains  

Microsoft Academic Search

Summary  Lactobacillus acidophilus M92, Lactobacillus plantarum L4 and Enterococcus faecium L3 were previously selected as probiotic strains on the base of in vitro selection criteria. To investigate functional properties of these three probiotic strains in vivo, Swiss albino mice were used as animal model. Survival, competition, adhesion and colonization were monitored in the gastrointestinal\\u000a tract, as well as the immunomodulating capability

J. Frece; B. Kos; J. Beganovi?; S. Vukovi?; J. Šuškovi?

2005-01-01

137

Structural and Functional Dissection of the Abp1 ADFH Actin-binding Domain Reveals Versatile In Vivo Adapter Functions  

SciTech Connect

Abp1 is a multidomain protein that regulates the Arp2/3 complex and links proteins involved in endocytosis to the actin cytoskeleton. All of the proposed cellular functions of Abp1 involve actin filament binding, yet the actin binding site(s) on Abp1 have not been identified, nor has the importance of actin binding for Abp1 localization and function in vivo been tested. Here, we report the crystal structure of the Saccharomyces cerevisiae Abp1 actin-binding actin depolymerizing factor homology (ADFH) domain and dissect its activities by mutagenesis. Abp1-ADFH domain and ADF/cofilin structures are similar, and they use conserved surfaces to bind actin; however, there are also key differences that help explain their differential effects on actin dynamics. Using point mutations, we demonstrate that actin binding is required for localization of Abp1 in vivo, the lethality caused by Abp1 overexpression, and the ability of Abp1 to activate Arp2/3 complex. Furthermore, we genetically uncouple ABP1 functions that overlap with SAC6, SLA1, and SLA2, showing they require distinct combinations of activities and interactions. Together, our data provide the first structural and functional view of the Abp1-actin interaction and show that Abp1 has distinct cellular roles as an adapter, linking different sets of ligands for each function.

Quintero-Monzon,O.; Rodal, A.; Strokopytov, B.; Almo, S.; Goode, B.

2005-01-01

138

Non-invasive in vivo imaging of pancreatic ?-cell function and survival - a perspective.  

PubMed

A major problem in medical research is to translate in vitro observations into the living organism. In this perspective, we discuss ongoing efforts to non-invasively image pancreatic islets/?-cells by techniques, such as magnetic resonance imaging and positron emission tomography, and present an experimental platform, which allows in vivo imaging of pancreatic ?-cell mass and function longitudinally and at the single-cell level. Following transplantation of pancreatic islets into the anterior chamber of the eye of mice and rats, these islets are studied by functional microscopic imaging. This imaging platform can be utilized to address fundamental aspects of pancreatic islet cell biology in vivo in health and disease. These include the dynamics of pancreatic islet vascularization, islet cell innervation, signal-transduction, change in functional ?-cell mass and immune responses. Moreover, we discuss the feasibility of studying human islet cell physiology and pathology in vivo as well as the potential of using the anterior chamber of the eye as a site for therapeutic transplantation in type 1 diabetes mellitus. PMID:21477063

Leibiger, I B; Caicedo, A; Berggren, P-O

2011-05-28

139

Non-invasive in vivo imaging of pancreatic ?-cell function and survival - a perspective  

PubMed Central

A major problem in medical research is to translate in vitro observations into the living organism. In this perspective, we discuss ongoing efforts to non-invasively image pancreatic islets/?-cells by techniques, such as magnetic resonance imaging and positron emission tomography, and present an experimental platform, which allows in vivo imaging of pancreatic ?-cell mass and function longitudinally and at the single-cell level. Following transplantation of pancreatic islets into the anterior chamber of the eye of mice and rats, these islets are studied by functional microscopic imaging. This imaging platform can be utilized to address fundamental aspects of pancreatic islet cell biology in vivo in health and disease. These include the dynamics of pancreatic islet vascularization, islet cell innervation, signal-transduction, change in functional ?-cell mass and immune responses. Moreover, we discuss the feasibility of studying human islet cell physiology and pathology in vivo as well as the potential of using the anterior chamber of the eye as a site for therapeutic transplantation in type 1 diabetes mellitus.

Leibiger, I. B.; Caicedo, A.; Berggren, P.-O.

2012-01-01

140

Direct link between RACK1 function and localization at the ribosome in vivo.  

PubMed

The receptor for activated C-kinase (RACK1), a conserved protein implicated in numerous signaling pathways, is a stoichiometric component of eukaryotic ribosomes located on the head of the 40S ribosomal subunit. To test the hypothesis that ribosome association is central to the function of RACK1 in vivo, we determined the 2.1-A crystal structure of RACK1 from Saccharomyces cerevisiae (Asc1p) and used it to design eight mutant versions of RACK1 to assess roles in ribosome binding and in vivo function. Conserved charged amino acids on one side of the beta-propeller structure were found to confer most of the 40S subunit binding affinity, whereas an adjacent conserved and structured loop had little effect on RACK1-ribosome association. Yeast mutations that confer moderate to strong defects in ribosome binding mimic some phenotypes of a RACK1 deletion strain, including increased sensitivity to drugs affecting cell wall biosynthesis and translation elongation. Furthermore, disruption of RACK1's position at the 40S ribosomal subunit results in the failure of the mRNA binding protein Scp160 to associate with actively translating ribosomes. These results provide the first direct evidence that RACK1 functions from the ribosome, implying a physical link between the eukaryotic ribosome and cell signaling pathways in vivo. PMID:19114558

Coyle, Scott M; Gilbert, Wendy V; Doudna, Jennifer A

2008-12-29

141

High Frequency of Luteal Phase Deficiency and Anovulation in Recreational Women Runners: Blunted Elevation in Follicle-Stimulating Hormone Observed during Luteal-Follicular Transition  

Microsoft Academic Search

The purposes of this investigation were to evaluate the character- istics of three consecutive menstrual cycles and to determine the frequency of luteal phase deficiency (LPD) and anovulation in a sam- ple of sedentary and moderately exercising, regularly menstruating women. For three consecutive menstrual cycles, subjects collected daily urine samples for analysis of FSH, estrone conjugates (E1C), pregnanediol-3-glucuronide (PdG), and

MARY JANE DE SOUZA; B. E. MILLER; A. B. LOUCKS; A. A. LUCIANO; L. S. PESCATELLO; C. G. CAMPBELL; B. L. LASLEY

142

Environmentally persistent free radicals decrease cardiac function before and after ischemia/reperfusion injury in vivo  

PubMed Central

Exposure to airborne particles is associated with increased cardiovascular morbidity and mortality. During the combustion of chlorine-containing hazardous materials and fuels, chlorinated hydrocarbons chemisorb to the surface of transition metal-oxide-containing particles, reduce the metal, and form an organic free radical. These radical-particle systems can survive in the environment for days and are called environmentally persistent free radicals (EPFRs). This study determined whether EPFRs could decrease left ventricular function before and after ischemia and reperfusion (I/R) in vivo. Male Brown Norway rats were dosed (8 mg/kg, i.t.) 24 hr prior to testing with particles containing the EPFR of 1, 2-dichlorobenzene (DCB230). DCB230 treatment decreased systolic and diastolic function. DCB230 also produced pulmonary and cardiac inflammation. After ischemia, systolic, but not diastolic function was significantly decreased in DCB230-treated rats. Ventricular function was not affected by I/R in control rats. There was greater oxidative stress in the heart and increased 8-isoprostane (biomarker of oxidative stress) in the plasma of treated vs control rats after I/R. These data demonstrate for the first time that DCB230 can produce inflammation and significantly decrease cardiac function at baseline and after I/R in vivo. Furthermore, these data suggest that EPFRs may be a risk factor for cardiac toxicity in healthy individuals and individuals with ischemic heart disease. Potential mechanisms involving cytokines/chemokines and/or oxidative stress are discussed.

Lord, Kevin; Moll, David; Lindsey, John K.; Mahne, Sarah; Raman, Girija; Dugas, Tammy; Cormier, Stephania; Troxlair, Dana; Lomnicki, Slawo; Dellinger, Barry; Varner, Kurt

2011-01-01

143

Environmentally persistent free radicals decrease cardiac function before and after ischemia/reperfusion injury in vivo.  

PubMed

Exposure to airborne particles is associated with increased cardiovascular morbidity and mortality. During the combustion of chlorine-containing hazardous materials and fuels, chlorinated hydrocarbons chemisorb to the surface of transition metal-oxide-containing particles, reduce the metal, and form an organic free radical. These radical-particle systems can survive in the environment for days and are called environmentally persistent free radicals (EPFRs). This study determined whether EPFRs could decrease left ventricular function before and after ischemia and reperfusion (I/R) in vivo. Male Brown-Norway rats were dosed (8?mg/kg, intratracheal) 24?h prior to testing with particles containing the EPFR of 1, 2-dichlorobenzene (DCB230). DCB230 treatment decreased systolic and diastolic function. DCB230 also produced pulmonary and cardiac inflammation. After ischemia, systolic, but not diastolic function was significantly decreased in DCB230-treated rats. Ventricular function was not affected by I/R in control rats. There was greater oxidative stress in the heart and increased 8-isoprostane (biomarker of oxidative stress) in the plasma of treated vs. control rats after I/R. These data demonstrate for the first time that DCB230 can produce inflammation and significantly decrease cardiac function at baseline and after I/R in vivo. Furthermore, these data suggest that EPFRs may be a risk factor for cardiac toxicity in healthy individuals and individuals with ischemic heart disease. Potential mechanisms involving cytokines/chemokines and/or oxidative stress are discussed. PMID:21385100

Lord, Kevin; Moll, David; Lindsey, John K; Mahne, Sarah; Raman, Girija; Dugas, Tammy; Cormier, Stephania; Troxlair, Dana; Lomnicki, Slawo; Dellinger, Barry; Varner, Kurt

2011-04-01

144

Stiffened yeast telomerase RNA supports RNP function in vitro and in vivo  

PubMed Central

The 1157-nt Saccharomyces cerevisiae telomerase RNA, TLC1, in addition to providing a 16-nt template region for reverse transcription, has been proposed to act as a scaffold for protein subunits. Although accessory subunits of the telomerase ribonucleoprotein (RNP) complex function even when their binding sites are relocated on the yeast telomerase RNA, the physical nature of the RNA scaffold has not been directly analyzed. Here we explore the structure–function organization of the yeast telomerase RNP by extensively stiffening the three long arms of TLC1, which connect essential and important accessory protein subunits Ku, Est1, and Sm7, to its central catalytic hub. This 956-nt triple-stiff-arm TLC1 (TSA-T) reconstitutes active telomerase with TERT (Est2) in vitro. Furthermore, TSA-T functions in vivo, even maintaining longer telomeres than TLC1 on a per RNA basis. We also tested functional contributions of each stiffened arm within TSA-T and found that the stiffened Est1 and Ku arms contribute to telomere lengthening, while stiffening the terminal arm reduces telomere length and telomerase RNA abundance. The fact that yeast telomerase tolerates significant stiffening of its RNA subunit in vivo advances our understanding of the architectural and functional organization of this RNP and, more broadly, our conception of the world of lncRNPs.

Lebo, Kevin J.; Zappulla, David C.

2012-01-01

145

Hepatitis C Virus-Infected Cells Downregulate NKp30 and Inhibit Ex Vivo NK Cell Functions.  

PubMed

Hepatitis C virus (HCV) successfully evades the immune system and establishes chronic infection in ?80% of cases. Immune evasion may involve modulating NK cell functions. Therefore, we developed a short-term assay to assess immediate effects of HCV-infected cells on ex vivo NK cytotoxicity and cytokine production. Natural cytotoxicity, Ab-dependent cell-mediated cytotoxicity, IFN-? production, and TNF-? production were all significantly inhibited by short-term direct exposure to HCV-infected hepatoma-derived Huh-7.5 cells. Inhibition required cell-to-cell contact and increased together with multiplicity of infection and HCV protein levels. Blocking potential interaction between HCV E2 and NK CD81 did not abrogate NK cell inhibition mediated by HCV-infected cells. We observed no change in expression levels of NKG2D, NKG2A, NKp46, or CD16 on NK cells exposed to HCV-infected Huh-7.5 cells for 5 h or of human histocompatibility-linked leukocyte Ag E on HCV-infected compared with uninfected Huh-7.5 cells. Inhibition of ex vivo NK functions did correspond with reduced surface expression of the natural cytotoxicity receptor NKp30, and downregulation of NKp30 was functionally reflected in reduced anti-NKp30 redirected lysis of P815 cells. Infection of Huh-7.5 cells with HCV JFH1T increased surface binding of an NKp30-IgG1 Fc? fusion protein, suggesting upregulation of an antagonistic NKp30 ligand on HCV-infected cells. Our assay demonstrates rapid inhibition of critical NK cell functions by HCV-infected cells. Similar localized effects in vivo may contribute to establishment of chronic HCV infection and associated phenotypic and functional changes in the NK population. PMID:23960237

Holder, Kayla A; Stapleton, Staci N; Gallant, Maureen E; Russell, Rodney S; Grant, Michael D

2013-08-19

146

Longitudinal assessment of endothelial function in the microvasculature of mice in-vivo.  

PubMed

Endothelial dysfunction is associated with early development of cardiovascular disease, making longitudinal measurements desirable. We devised a protocol using laser Doppler imaging (LDI) and iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP) to assess the skin microcirculation longitudinally in mice every 4 weeks for 24 weeks in two groups of C57BL/6 mice, chow versus high-cholesterol diet(known to induce endothelial dysfunction). LDI measurements were compared with vascular function (isometric tension) measured using wire myography in the tail artery in response to ACh and SNP. Microvascular responses to ACh were significantly reduced in cholesterol-fed versus chow-fed mice from week 4 onwards (P<0.005, ANOVA). Pre-treatment with N(G)-nitro-L-arginine methyl-ester-hydrochloride (L-NAME) showed a significant reduction in ACh response compared with vehicle-treated animals (P<0.05) at baseline and at 12 weeks. In cholesterol-fed mice, ACh responses were 226 ± 21 and 180 ± 21 AU (P=0.03) before and after L-NAME, respectively. A reduction in ex-vivo ACh response was detected in the tail artery in cholesterol-fed mice, and a significant correlation found between peak microvascular ACh response and maximum ACh response in the tail artery (r=0.699, P=0.017). No changes were found in SNP responses in the microvasculature or tail artery. Using this protocol, we have shown longitudinal decreases in microvascular endothelial function to cholesterol feeding. L-NAME studies confirm that the reduced vasodilatation to ACh in cholesterol-fed mice was mediated partly through reduced NO bioavailability. Wire myography of tail arteries confirmed that in-vivo measurements of microvascular function reflect ex-vivo vascular function in other beds. Longitudinal assessments of skin microvascular function in mice could provide a useful translatable model for assessing early endothelial dysfunction. PMID:23123637

Belch, Jill J F; Akbar, Naveed; Alapati, Venkateswara; Petrie, John; Arthur, Simon; Khan, Faisel

2012-10-31

147

IN VIVO Function of Rare G6pd Variants from Natural Populations of DROSOPHILA MELANOGASTER  

PubMed Central

From 1981 to 1983, 15,097 X-chromosomes were genetically extracted from a number of North American populations of D. melanogaster and were electrophoretically screened for rare mobility and activity variants of glucose-6-phosphate dehydrogenase (G6PD). Overall, 13 rare variants were recovered for a frequency of about 10-3. Eleven variants affect electrophoretic mobility and are apparently structural, and two variants exhibit low G6PD activity. One low activity variant is closely associated with a P-element insertion at 18D12-13—all of the variants were subjected to the previously described genetic scheme used to identify relative in vivo activity differences between the two common electrophoretic variants associated with the global polymorphism. Most of the rare variants exhibit apparent in vivo activities that are similar to one or the other of the common variants, and these specific rare variants appear to be geographically widespread. Several variants have significantly reduced function. All of the variants were measured for larval specific activity for G6PD as a first measure of in vitro activity. It appears that specific activity alone is not a sufficient predictor for G6PD in vivo function.

Eanes, Walter F.; Hey, Jody

1986-01-01

148

Dynamic contrast-enhanced optical imaging of in vivo organ function  

PubMed Central

Abstract. Conventional approaches to optical small animal molecular imaging suffer from poor resolution, limited sensitivity, and unreliable quantitation, often reducing their utility in practice. We previously demonstrated that the in vivo dynamics of an injected contrast agent could be exploited to provide high-contrast anatomical registration, owing to the temporal differences in each organ’s response to the circulating fluorophore. This study extends this approach to explore whether dynamic contrast-enhanced optical imaging (DyCE) can allow noninvasive, in vivo assessment of organ function by quantifying the differing cellular uptake or wash-out dynamics of an agent in healthy and damaged organs. Specifically, we used DyCE to visualize and measure the organ-specific uptake dynamics of indocyanine green before and after induction of transient liver damage. DyCE imaging was performed longitudinally over nine days, and blood samples collected at each imaging session were analyzed for alanine aminotransferase (ALT), a liver enzyme assessed clinically as a measure of liver damage. We show that changes in DyCE-derived dynamics of liver and kidney dye uptake caused by liver damage correlate linearly with ALT concentrations, with an r2 value of 0.91. Our results demonstrate that DyCE can provide quantitative, in vivo, longitudinal measures of organ function with inexpensive and simple data acquisition.

Amoozegar, Cyrus B.; Wang, Tracy; Bouchard, Matthew B.; McCaslin, Addason F. H.; Blaner, William S.; Levenson, Richard M.; Hillman, Elizabeth M. C.

2012-01-01

149

Intracardiac echocardiography: in vitro and in vivo validation for right ventricular volume and function.  

PubMed

To determine the feasibility and accuracy of intracardiac ultrasonography (ICUS) for the measurement of right ventricular (RV) volumes and function, a 10 MHz ICUS catheter was used in an in vitro and in vivo model. In the in vitro study, 16 sheep hearts were imaged. Sequential cross-sectional images from RV apex to base were recorded during a calibrated pullback. Volumes were calculated by applying Simpson's algorithm. ICUS-obtained volumes correlated well with actual volumes (standard error of estimate [SEE] = 2.3 ml, r = 0.98). For the in vivo study, a beating-heart canine model was used (31 hemodynamic stages in six dogs). Actual volumes were measured by an intracavitary balloon connected to an external column. Sequential cross-sectional images were recorded during the ICUS catheter pullback from apex to base of the RV, and volumes calculated by Simpson's algorithm. Good correlations were observed between ICUS and actual values for diastolic (SEE = 4.1 ml, r = 0.97), systolic (SEE = 3.4 ml, r = 0.96), and ejection fraction (SEE = 3.1%, r = 0.87) values. This new technique can accurately quantitate RV volumes, can function both in vitro and in vivo, and has the potential for increasing applications to questions of clinical and research interest. PMID:8579028

Vazquez de Prada, J A; Chen, M H; Guerrero, J L; Padial, L R; Jiang, L; Schwammenthal, E; Sagie, A; Weyman, A E; Levine, R A; Chen, C

1996-02-01

150

In vivo cardiac anatomical and functional effects of wheel running in mice by magnetic resonance imaging.  

PubMed

Physical activity is frequently used as a strategy to decrease pathogenesis and improve outcomes in chronic pathologies such as metabolic or cardiac diseases. In mice, it has been shown that voluntary wheel running (VWR) could induce an aerobic training effect and may provide a means of exploring the relationship between physical activity and the progression of pathology, or the effect of a drug on locomotor activity. To the best of our knowledge, in vivo magnetic resonance imaging (MRI) and other non-invasive methods had not been investigated for training evaluation in mice; therefore, it was proposed to test an MRI method coupled with a cardiorespiratory gating system on C57Bl/6 mice for in vivo heart anatomical and functional characterization in both trained and untrained animals. Twenty mice were either assigned to a 12-week VWR program or to a control group (CON - no wheel in the cage). At week 12, MRI scans showed an increase in the left ventricular (LV) wall mass in the VWR group compared with the CON group. The ex vivo measurements also found an increase in the heart and LV weight, as well as an increase in oxidative enzyme activities (i.e. cytochrome c oxidase [COx] in the soleus). In addition, correlations have been observed between ex vivo LV/body weight ratio, COx activity in the soleus and in vivo MRI LV wall mass/body weight. In conclusion, mouse cardiac MRI methods coupled with a cardio-respiratory gating system are sufficiently effective and feasible for non-invasive, training-induced heart hypertrophy characterization, and may be used for longitudinal training level follow-up in mouse models of cardiovascular and metabolic diseases. PMID:22328593

Aufradet, Emeline; Bessaad, Amine; Alsaid, Hasan; Schäfer, Florian; Sigovan, Monica; De Souza, Geneviève; Chirico, Erica; Martin, Cyril; Canet-Soulas, Emmanuelle

2012-02-10

151

Protein profile of the luteal phase endometrium by tissue microarray assessment.  

PubMed

To investigate the luteal phase endometrial expression of leukemia inhibitor factor (LIF), insulin-like growth factor 1 (IGF-1), progesterone receptor (PR), claudin 4 (CLDN4), vascular-endothelial growth factor receptor 3 (VEGFR-3), bone morphogenetic protein 4 (BMP-4) and citokeratin 7 (CK-7), we obtained luteal phase endometrial samples from 52 women. Samples were dated and integrated using a tissue microarray (TMA). Samples were immunostained for LIF, IGF-1, PR, CLDN4, VEGFR-3, BMP-4 and CK-7. Frequencies of positive expressions at the early, mid and late luteal phases were compared by two proportions test. Concomitant expression of these proteins was assessed with Chi-square or Fischer's test. The frequency of LIF was positively correlated to the frequency of IGF-1 (r = 0.99; p < 0.05) and PR (r = 0.99; p < 0.05), and the correlation between IGF-1 and PR tended to be significant (r = 0.98; p < 0.1). The expression of PR was associated with the absence of CLDN4 (p < 0.001). Thus, expression of LIF, IGF-1 and PR are correlated during the luteal phase, and immunohistochemistry for these proteins might be used to assist in the assessment of endometrial maturation. In addition, the expression of CLDN4 and PR was not concomitant, warranting further investigation on the relationship of their endometrial expression. PMID:19557595

Serafini, Paulo; Da Rocha, André Monteiro; De Toledo Osório, Cyntia Aparecida Bueno; Smith, Gary Daniel; Hassun, Pericles Assad; da Silva, Ismael Guerreiro Dale Cotrim Guerreiro; Da Motta, Eduardo Leme Alves; Baracat, Edmund Chada

2009-09-01

152

Apoptosis in canine corpus luteum during spontaneous and prostaglandin-induced luteal regression  

Microsoft Academic Search

Spontaneous luteal regression and prostaglandin-induced luteolysis in bitches were evaluated by measuring the apoptotic index for DNA fragmentation and the relative level of Bax gene expression in ovaries removed from nine untreated nonpregnant bitches at selected times during diestrus and in nine pregnant bitches after 1 day of administering abortive doses of a PGF-analog gel formulation given intravaginally at selected

Giulio Aiudi; Maria Albrizio; Michele Caira; Mario Cinone

2006-01-01

153

Luteal estradiol supplementation in gonadotropin-releasing hormone antagonist cycles for infertile patients in vitro fertilization  

PubMed Central

Objective To evaluate the effect of the addition of estradiol to luteal progesterone supplementation in GnRH antagonist cycles for infertile patients undergoing IVF/ICSI. Methods One hundred and ten infertile patients, aged 28 to 39 years, were recruited for this prospective randomized study. They were randomly assigned to receive vaginal progesterone gel (Crinone) along with 4 mg estradiol valerate (group 1, n=55) or only Crinone (group 2, n=55) for luteal support. A GnRH antagonist multiple dose protocol using recombinant human FSH was used for controlled ovarian stimulation (COS) in all of the subjects. The COS results and pregnancy outcomes of the two groups were compared. Results Group 1 and 2 were comparable with respect to the patient characteristics. The COS and IVF results were also comparable between the two groups. There were no differences in the clinical pregnancy rate (PR) and multiple PR between the two groups. However, the embryo implantation rate were significantly higher in group 1 than that in group 2 (22.2% vs. 13.3%, p=0.035). The incidence of luteal vaginal bleeding (LVB) was significantly lower in group 1 (7.4% vs. 27.8%, p=0.010). Conclusion The addition of estradiol to luteal progesterone supplementation in GnRH antagonist cycles reduces the incidence of LVB and increases the embryo implantation rate in infertile patients undergoing IVF/ICSI.

Kwon, Su-Kyoung; Lee, Kyung-Hee; Jeon, Il Kyung; Ahn, Jun-Woo; Kim, Sung-Hoon; Chae, Hee-Dong; Kang, Byung-Moon

2013-01-01

154

Impact of ovarian stimulation on mid-luteal endometrial tissue and secretion markers of receptivity.  

PubMed

The objective of this study was to investigate the effect of ovarian stimulation for IVF on endometrial secretion and tissue markers of receptivity in the mid-luteal phase. In 10 oocyte donors, endometrial secretions and biopsies were sampled 5 days after spontaneous ovulation and oocyte retrieval in consecutive cycles. Four subjects received progesterone in the luteal phase of the stimulated cycles. Mid-luteal endometrial maturation in the stimulated cycle was compared with the spontaneous cycle, by histological dating, Ki-67, oestrogen receptor (ER) and progesterone receptor (PR) expression, secretion levels of leukaemia inhibitory factor (LIF), glycodelin A (GdA) and progesterone, and protein profile. No significant differences in histological markers, expression of Ki-67, PR, ER, secretion protein profiles or concentrations of LIF, GdA, or progesterone were observed when comparing natural with stimulated cycles. Progesterone supplementation of stimulated cycles was associated with significantly lower Ki-67 (P = 0.03) and ER (P = 0.04) expression compared with the non-supplemented stimulated cycle. In this pilot study, ovarian stimulation was not demonstrated to alter the studied markers of endometrial maturation in the mid-luteal phase. PMID:18854111

van der Gaast, M H; Classen-Linke, I; Krusche, C A; Beier-Hellwig, K; Fauser, B C J M; Beier, H M; Macklon, N S

2008-10-01

155

Zebrafish primary testis tissue culture: an approach to study testis function ex vivo.  

PubMed

To develop new tools to study the regulation of testis physiology in teleost fish, a medium-term ex vivo organ culture system was adopted for zebrafish testis tissue. The addition of 100nM 11-ketotestosterone to the system supported complete spermatogenesis, as determined by morphological, molecular and immunohistochemical analyses. Under basal conditions, however, the development of differentiated spermatogonia, spermatocytes, and spermatids was seriously disturbed, probably related to the rapid (within 2 days) down-regulation of the steroidogenic system. Forskolin (0.5microM) stimulated acute androgen release from freshly removed tissue and partially prevented down-regulation of the steroidogenic system. The present ex vivo culture system can serve as a tool to evaluate effects of a wide range of substances on the two main functions of the testis, spermatogenesis and hormone production. PMID:19298819

Leal, Marcelo C; de Waal, Paul P; García-López, Angel; Chen, Shi X; Bogerd, Jan; Schulz, Rüdiger W

2009-03-17

156

Relationship between in vivo activity and in vitro measures of function and stability of a protein  

SciTech Connect

The in vivo activities of mutant proteins are readily measured and can potentially be used to estimate changes in in vitro properties such as stability or function, but this connection has not been rigorously established. Gene V protein is a small protein produced by bacteriophage f1 that binds to single-stranded DNA and to RNA and for which fitness can be assayed both in vivo and in vitro. We have assembled a large number of temperature-sensitive mutants of the gene V protein of bacteriophage f1 and measured their ability to support phage growth and replication in vivo. We have also purified many of these mutant gene V proteins and measured their stabilities and ssDNA binding affinities in vitro. Mutations at surface residues frequently yielded temperature-sensitive mutants, but remarkably, no overall correlation between in vivo activity and in vitro measures of either stability or function was found for this group. Mutations at buried residues often lead to the temperature-sensitive phenotype. At buried sites temperature sensitivity was strongly correlated with in vitro stability changes, but not with in vitro ssDNA binding affinity. The implication of these observations for protein engineering efforts is that phenotypes conferred by amino acid substitutions at buried sites can be used to identify mutants whose stabilities fall into ranges of interest, while phenotypes of mutants with surface substitutions may be much less readily interpreted, even in the case of a single-stranded-DNA-binding protein. 54 refs., 3 figs., 2 tabs.

Sandberg, W.S.; Schlunk, P.M.; Zabin, H.G. [Univ. of Chicago, IL (United States)] [and others

1995-09-19

157

Microfibril-associated Glycoprotein 2 (MAGP2) Loss of Function Has Pleiotropic Effects in Vivo.  

PubMed

Microfibril-associated glycoprotein (MAGP) 1 and 2 are evolutionarily related but structurally divergent proteins that are components of microfibrils of the extracellular matrix. Using mice with a targeted inactivation of Mfap5, the gene for MAGP2 protein, we demonstrate that MAGPs have shared as well as unique functions in vivo. Mfap5(-/-) mice appear grossly normal, are fertile, and have no reduction in life span. Cardiopulmonary development is typical. The animals are normotensive and have vascular compliance comparable with age-matched wild-type mice, which is indicative of normal, functional elastic fibers. Loss of MAGP2 alone does not significantly alter bone mass or architecture, and loss of MAGP2 in tandem with loss of MAGP1 does not exacerbate MAGP1-dependent osteopenia. MAGP2-deficient mice are neutropenic, which contrasts with monocytopenia described in MAGP1-deficient animals. This suggests that MAGP1 and MAGP2 have discrete functions in hematopoiesis. In the cardiovascular system, MAGP1;MAGP2 double knockout mice (Mfap2(-/-);Mfap5(-/-)) show age-dependent aortic dilation. These findings indicate that MAGPs have shared primary functions in maintaining large vessel integrity. In solid phase binding assays, MAGP2 binds active TGF?1, TGF?2, and BMP2. Together, these data demonstrate that loss of MAGP2 expression in vivo has pleiotropic effects potentially related to the ability of MAGP2 to regulate growth factors or participate in cell signaling. PMID:23963447

Combs, Michelle D; Knutsen, Russell H; Broekelmann, Thomas J; Toennies, Holly M; Brett, Thomas J; Miller, Chantel A; Kober, Daniel L; Craft, Clarissa S; Atkinson, Jeffrey J; Shipley, J Michael; Trask, Barbara C; Mecham, Robert P

2013-08-20

158

In Vivo Imaging of the Photoreceptor Mosaic in Retinal Dystrophies and Correlations with Visual Function  

PubMed Central

Purpose To relate in vivo microscopic retinal changes to visual function in patients who have various forms of retinal dystrophy. Methods The UC Davis Adaptive Optics (AO) fundus camera was used to acquire in vivo retinal images at the cellular level. Visual function tests consisting of visual fields, multifocal electroretinography (mfERG), and contrast sensitivity were measured in all subjects by using stimuli that were coincident with areas imaged. Five patients with different forms of retinal dystrophy and three control subjects were recruited. Cone densities were quantified for all retinal images. Results In all images of diseased retinas, there were extensive areas of dark space between groups of photoreceptors, where no cone photoreceptors were evident. These irregular features were not seen in healthy retinas, but were apparent in patients with retinal dystrophy. There were significant correlations between functional vision losses and the extent to which these irregularities, quantified by cone density, occurred in retinal images. Conclusions AO fundus imaging is a reliable technique for assessing and quantifying the changes in the photoreceptor layer as disease progresses. Furthermore, this technique can be useful in cases where visual function tests provide borderline or ambiguous results, as it allows visualization of individual photoreceptors.

Choi, Stacey S.; Doble, Nathan; Hardy, Joseph L.; Jones, Steven M.; Keltner, John L.; Olivier, Scot S.; Werner, John S.

2008-01-01

159

Biomechanical regulation of vascular smooth muscle cell functions: from in vitro to in vivo understanding.  

PubMed

Vascular smooth muscle cells (VSMCs) have critical functions in vascular diseases. Haemodynamic factors are important regulators of VSMC functions in vascular pathophysiology. VSMCs are physiologically active in the three-dimensional matrix and interact with the shear stress sensor of endothelial cells (ECs). The purpose of this review is to illustrate how haemodynamic factors regulate VSMC functions under two-dimensional conditions in vitro or three-dimensional co-culture conditions in vivo. Recent advances show that high shear stress induces VSMC apoptosis through endothelial-released nitric oxide and low shear stress upregulates VSMC proliferation and migration through platelet-derived growth factor released by ECs. This differential regulation emphasizes the need to construct more actual environments for future research on vascular diseases (such as atherosclerosis and hypertension) and cardiovascular tissue engineering. PMID:24152813

Qiu, Juhui; Zheng, Yiming; Hu, Jianjun; Liao, Donghua; Gregersen, Hans; Deng, Xiaoyan; Fan, Yubo; Wang, Guixue

2013-10-23

160

Nonsupplemented luteal phase characteristics after the administration of recombinant human chorionic gonadotropin, recombinant luteinizing hormone, or gonadotropin-releasing hormone (GnRH) agonist to induce final oocyte maturation in in vitro fertilization patients after ovarian stimulation with recombinant follicle-stimulating hormone and GnRH antagonist cotreatment  

Microsoft Academic Search

Replacing GnRH agonist cotreatment for the prevention of a premature rise\\u000a in LH during ovarian stimulation for in vitro fertilization (IVF) by the\\u000a late follicular phase administration of GnRH antagonist may render\\u000a supplementation of the luteal phase redundant, because of the known rapid\\u000a recovery of pituitary function after antagonist cessation. This randomized\\u000a two-center study was performed to compare nonsupplemented luteal

N. S. Macklon; M. J. C. Eijkemans; M. Ludwig; R. E. Felberbaum; K. Diedrich; S. Bustion; E. Loumaye; B. C. J. M. Fauser; N. G. M. Beckers

2003-01-01

161

Fatigue alters in vivo function within and between limb muscles during locomotion  

PubMed Central

Muscle fatigue, a reduction in force as a consequence of exercise, is an important factor for any animal that moves, and can result from both peripheral and/or central mechanisms. Although much is known about whole-limb force generation and activation patterns in fatigued muscles under sustained isometric contractions, little is known about the in vivo dynamics of limb muscle function in relation to whole-body fatigue. Here we show that limb kinematics and contractile function in the lateral (LG) and medial (MG) gastrocnemius of helmeted guineafowl (Numida meleagris) are significantly altered following fatiguing exercise at 2?m?s?1 on an inclined treadmill. The two most significant findings were that the variation in muscle force generation, measured directly from the muscles' tendons, increased significantly with fatigue, and fascicle shortening in the proximal MG, but not the distal MG, decreased significantly with fatigue. We suggest that the former is a potential mechanism for decreased stability associated with fatigue. The region-specific alteration of fascicle behaviour within the MG as a result of fatigue suggests a complex response to fatigue that probably depends on muscle–aponeurosis and tendon architecture not previously explored. These findings highlight the importance of studying the integrative in vivo dynamics of muscle function in response to fatigue.

Higham, Timothy E.; Biewener, Andrew A.

2008-01-01

162

Selection of antibodies for intracellular function using a two-hybrid in vivo system  

PubMed Central

Expression of antibodies inside cells has been used successfully to ablate protein function. This finding suggests that the technology should have an impact on disease treatment and in functional genomics where proteins of unknown function are predicted from genomic sequences. A major hindrance is the paucity of antibodies that function in eukaryotic cells, presumably because the antibodies fold incorrectly in the cytoplasm. To overcome this problem, we have developed an in vivo assay for functional intracellular antibodies using a two-hybrid approach. In this assay, antibody, as single-chain Fv (scFv) linked to a transcriptional transactivation domain, can interact with a target antigen, linked to a LexA-DNA binding domain, and thereby activate a reporter gene. We find that several characterized antibodies can bind their target antigen in eukaryotic cells in this two-hybrid format, and we have been able to isolate intracellular binders from among sets of scFv that can bind antigen in vitro. Furthermore, we show a model selection in which a single scFv was isolated from a mixture of half a million clones, indicating that this is a robust procedure that should facilitate capture of antibody specificities from complex mixtures. The approach can provide the basis for de novo selection of intracellular scFv from libraries, such as those made from spleen RNA after immunization with antigen, for intracellular analysis of protein function based only on genomic or cDNA sequences.

Visintin, Michela; Tse, Eric; Axelson, Hakan; Rabbitts, Terence H.; Cattaneo, Antonino

1999-01-01

163

Fish meal supplementation increases bovine plasma and luteal tissue omega-3 fatty acid composition.  

PubMed

The objective of this experiment was to determine if dietary inclusion of fish meal would increase plasma and luteal tissue concentrations of eicosapentaenoic and docosahexaenoic acids. Seventeen nonlactating Angus cows (2 to 8 yr of age) were housed in individual pens and fed a corn silage-based diet for approximately 60 d. Diets were supplemented with fish meal at 5% DMI (a rich source of eicosapentaenoic acid and docosahexaenoic acid; n = 9 cows) or corn gluten meal at 6% DMI (n = 8 cows). Body weights and jugular blood samples were collected immediately before the initiation of supplementation and every 7 d thereafter for 56 d to monitor plasma n-3 fatty acid composition and BW. Estrous cycles were synchronized using 2 injections of PGF(2?) administered at 14-d intervals. The ovary bearing the corpus luteum was surgically removed at midcycle (between d 10 and 12) after estrus synchronization, which corresponded to approximately d 60 of supplementation. The ovary was transported to the laboratory, and approximately 1.5 g of luteal tissue was stored at -80°C until analyzed for n-3 fatty acid content. Initial and ending BW did not differ (P > 0.10) between cows supplemented with fish meal and those with corn gluten meal. Plasma eicosapentaenoic acid was greater (P < 0.05) beginning at d 7 of supplementation and docosahexaenoic was greater (P < 0.05) beginning at d 14 of supplementation for cows receiving fish meal. Luteal tissue collected from fish meal-supplemented cows had greater (P < 0.05) luteal n-3 fatty acids and reduced (P < 0.05) arachidonic acid and n-6 to n-3 ratio as compared with tissue obtained from cows supplemented with corn gluten meal. Our data show that fish meal supplementation increases luteal n-3 fatty acid content and reduces available arachidonic acid content, the precursor for PGF(2?). The increase in luteal n-3 fatty acids may reduce PGF(2?) intraluteal synthesis after breeding resulting in increased fertility in cattle. PMID:22003234

White, N R; Burns, P D; Cheatham, R D; Romero, R M; Nozykowski, J P; Bruemmer, J E; Engle, T E

2011-10-14

164

Noninvasive in vivo model demonstrating the effects of autonomic innervation on pancreatic islet function.  

PubMed

The autonomic nervous system is thought to modulate blood glucose homeostasis by regulating endocrine cell activity in the pancreatic islets of Langerhans. The role of islet innervation, however, has remained elusive because the direct effects of autonomic nervous input on islet cell physiology cannot be studied in the pancreas. Here, we used an in vivo model to study the role of islet nervous input in glucose homeostasis. We transplanted islets into the anterior chamber of the eye and found that islet grafts became densely innervated by the rich parasympathetic and sympathetic nervous supply of the iris. Parasympathetic innervation was imaged intravitally by using transgenic mice expressing GFP in cholinergic axons. To manipulate selectively the islet nervous input, we increased the ambient illumination to increase the parasympathetic input to the islet grafts via the pupillary light reflex. This reduced fasting glycemia and improved glucose tolerance. These effects could be blocked by topical application of the muscarinic antagonist atropine to the eye, indicating that local cholinergic innervation had a direct effect on islet function in vivo. By using this approach, we found that parasympathetic innervation influences islet function in C57BL/6 mice but not in 129X1 mice, which reflected differences in innervation densities and may explain major strain differences in glucose homeostasis. This study directly demonstrates that autonomic axons innervating the islet modulate glucose homeostasis. PMID:23236142

Rodriguez-Diaz, Rayner; Speier, Stephan; Molano, Ruth Damaris; Formoso, Alexander; Gans, Itai; Abdulreda, Midhat H; Cabrera, Over; Molina, Judith; Fachado, Alberto; Ricordi, Camillo; Leibiger, Ingo; Pileggi, Antonello; Berggren, Per-Olof; Caicedo, Alejandro

2012-12-10

165

Noninvasive in vivo model demonstrating the effects of autonomic innervation on pancreatic islet function  

PubMed Central

The autonomic nervous system is thought to modulate blood glucose homeostasis by regulating endocrine cell activity in the pancreatic islets of Langerhans. The role of islet innervation, however, has remained elusive because the direct effects of autonomic nervous input on islet cell physiology cannot be studied in the pancreas. Here, we used an in vivo model to study the role of islet nervous input in glucose homeostasis. We transplanted islets into the anterior chamber of the eye and found that islet grafts became densely innervated by the rich parasympathetic and sympathetic nervous supply of the iris. Parasympathetic innervation was imaged intravitally by using transgenic mice expressing GFP in cholinergic axons. To manipulate selectively the islet nervous input, we increased the ambient illumination to increase the parasympathetic input to the islet grafts via the pupillary light reflex. This reduced fasting glycemia and improved glucose tolerance. These effects could be blocked by topical application of the muscarinic antagonist atropine to the eye, indicating that local cholinergic innervation had a direct effect on islet function in vivo. By using this approach, we found that parasympathetic innervation influences islet function in C57BL/6 mice but not in 129X1 mice, which reflected differences in innervation densities and may explain major strain differences in glucose homeostasis. This study directly demonstrates that autonomic axons innervating the islet modulate glucose homeostasis.

Rodriguez-Diaz, Rayner; Speier, Stephan; Molano, Ruth Damaris; Formoso, Alexander; Gans, Itai; Abdulreda, Midhat H.; Cabrera, Over; Molina, Judith; Fachado, Alberto; Ricordi, Camillo; Leibiger, Ingo; Pileggi, Antonello; Berggren, Per-Olof; Caicedo, Alejandro

2012-01-01

166

Numerical and In Vivo Validation of Fast Cine DENSE MRI for Quantification of Regional Cardiac Function  

PubMed Central

Quantitative assessment of regional cardiac function can improve the accuracy of detecting wall motion abnormalities due to heart disease. While recently developed fast cine displacement-encoded with stimulated echoes (DENSE) MRI is a promising modality for the quantification of regional myocardial function, it has not been validated for clinical applications. The purpose of this study, therefore, was to validate the accuracy of fast cine DENSE MRI with numerical simulation and in vivo experiments. A numerical phantom was generated to model physiologically relevant deformation of the heart, and the accuracy of fast cine DENSE was evaluated against the numerical reference. For in vivo validation, 12 controls and 13 heart disease patients were imaged using both fast cine DENSE and myocardial tagged MRI. Numerical simulation demonstrated that the echo-combination DENSE reconstruction method is relatively insensitive to clinically relevant resonance frequency offsets. The strain measurements by fast cine DENSE and the numerical reference were strongly correlated and in excellent agreement (mean difference=0.00; 95% limits of agreement were 0.01 and ?0.02). The strain measurements by fast cine DENSE and myocardial tagged MRI were strongly correlated (correlation coefficient = 0.92) and in good agreement (mean difference=0.01; 95% limits of agreement were 0.07 and ?0.04).

Feng, Li; Donnino, Robert; Babb, James; Axel, Leon; Kim, Daniel

2009-01-01

167

Tumor regression in vivo by photothermal therapy based on gold-nanorod-loaded, functional nanocarriers.  

PubMed

We developed a very effective hyperthermia system for successful photothermal cancer therapy. Instead of applying individual gold nanorods (GNRs) that can absorb NIR light, GNRs were loaded into functional nanocarriers that could provide stable storage of GNRs and selective delivery to a target tumor site. The functional nanocarriers (chitosan-conjugated, Pluronic-based nanocarriers) were prepared by chemically cross-linking Pluronic F 68 with chitosan conjugation to form a flexible, soft, and excellent reservoir for biomacromolecules as well as tumor targeting. In vivo characteristics of the nanocarriers including a long circulation time, a good tumor accumulation, and low liver uptake were previously characterized by us. When GNRs were delivered by using these nanocarriers, much enhanced in vitro cellular uptake and a photothermal effect were observed for a cancer cell line. More importantly, an intravenous injection of this system followed by NIR laser irradiation to the tumor site resulted in a very efficient thermolysis in vivo. Thus, apparently complete tumor resorption was achieved without damage to the surrounding tissue, suggesting a promising candidate for clinical phototherapeutic applications. PMID:21344891

Choi, Won Il; Kim, Ja-Young; Kang, Chul; Byeon, Clare C; Kim, Young Ha; Tae, Giyoong

2011-02-23

168

In vivo and in vitro HeNe laser effects on phagocyte functions  

SciTech Connect

The goal of this work was to evaluate the effect of helium-neon (HeNe) laser irradiation on immunocompetent cells. We used the in vivo skin window method and in vitro granulocyte function tests. The study of cellular migration showed a marked decrease in vitro and in vivo in a dose-independent manner. Superoxide release was not modified by laser irradiation. The granulocyte's aggregation, when using PHA and PMA, presented a reduction that was statistically very significant, not as a subordinate dose. An increase of the release of ATP was demonstrated only at 4 joules and precedes granulocyte aggregation. When using Ca2+ ionophore A23187 as stimulus, laser irradiation at 1, 2 or 4J did not show any modification of granulocyte aggregation. The monoclonal antibody 60.1, which identifies a membrane antigen fundamental for aggregation and chemotaxis, is expressed in normal amounts on granulocyte membranes both before and after irradiation with a HeNe laser. In fact, laser irradiation preferentially attacks the area of the cellular centrosome that determines a modification of cellular morphology. The electron microscope and immunofluorescence study with a monoclonal antibody have pointed out a disorganization of the microtubules. The alteration of some of the granulocyte functions is correlated to the damage in the centrioles. The granulocyte mitochondrial system and surface membrane remain intact, and this explains the normal production and release of free radicals. Further experiments are necessary to evaluate the clinical application of lasers in various diseases with immunophagocytic pathogenesis.

Ricevuti, G.; Mazzone, A.; Monaia, C.; Fratino, P.; Degiulio, R.; Dell'Acqua, R.; Leonardi, G.; Jucci, A.; Sacchi, S. (Univ. of Pavia (Italy))

1989-10-01

169

Tartary buckwheat improves cognition and memory function in an in vivo amyloid-?-induced Alzheimer model.  

PubMed

Protective effects of Tartary buckwheat (TB) and common buckwheat (CB) on amyloid beta (A?)-induced impairment of cognition and memory function were investigated in vivo in order to identify potential therapeutic agents against Alzheimer's disease (AD) and its associated progressive memory deficits, cognitive impairment, and personality changes. An in vivo mouse model of AD was created by injecting the brains of ICR mice with A?(25-35), a fragment of the full-length A? protein. Damage of mice recognition ability through following A?(25-35) brain injections was confirmed using the T-maze test, the object recognition test, and the Morris water maze test. Results of behavior tests in AD model showed that oral administration of the methanol (MeOH) extracts of TB and CB improved cognition and memory function following A?(25-35) injections. Furthermore, in groups receiving the MeOH extracts of TB and CB, lipid peroxidation was significantly inhibited, and nitric oxide levels in tissue, which are elevated by injection of A?(25-35), were also decrease. In particular, the MeOH extract of TB exerted a stronger protective activity than CB against A?(25-35)-induced memory and cognition impairment. The results indicate that TB may play a promising role in preventing or reversing memory and cognition loss associated with A?(25-35)-induced AD. PMID:23219778

Choi, Ji Yeon; Cho, Eun Ju; Lee, Hae Song; Lee, Jeong Min; Yoon, Young-Ho; Lee, Sanghyun

2012-11-28

170

An In Vivo Functional Screen Uncovers miR-150-Mediated Regulation of Hematopoietic Injury Response  

PubMed Central

Summary Hematopoietic stem and progenitor cells are often undesired targets of chemotherapies, leading to hematopoietic suppression requiring careful clinical management. Whether microRNAs control hematopoietic-injury response is largely unknown. We report a novel in vivo gain-of-function screen and identification of miR-150 as an inhibitor of hematopoietic recovery upon 5-fluorouracil-induced injury. Utilizing a bone marrow transplant model with a barcoded microRNA-library, we screened for barcode abundance in peripheral blood of recipient mice before and after 5-fluorouracil treatment. Overexpression of screen-candidate miR-150 resulted in significantly slowed recovery rates across major blood lineages, with associated impairment of bone marrow clonogenic potential. Conversely, platelets and myeloid cells from miR-150-null marrow recovered faster after 5-fluorouracil treatment. Heterozygous knockout of c-myb, a conserved target of miR-150, partially phenocopied miR-150 forced expression. Our data highlight the role of microRNAs in controlling hematopoietic-injury response, and demonstrate the power of in vivo functional screens for studying microRNAs in normal tissue physiology.

Adams, Brian D.; Guo, Shangqin; Bai, Haitao; Guo, Yanwen; Megyola, Cynthia; Cheng, Jijun; Heydari, Kartoosh; Xiao, Changchun; Reddy, E. Premkumar; Lu, Jun

2012-01-01

171

Ena/VASP is required for endothelial barrier function in vivo  

PubMed Central

Enabled/vasodilator-stimulated phosphoprotein (Ena/VASP) proteins are key actin regulators that localize at regions of dynamic actin remodeling, including cellular protrusions and cell–cell and cell–matrix junctions. Several studies have suggested that Ena/VASP proteins are involved in the formation and function of cellular junctions. Here, we establish the importance of Ena/VASP in endothelial junctions in vivo by analysis of Ena/VASP-deficient animals. In the absence of Ena/VASP, the vasculature exhibits patterning defects and lacks structural integrity, leading to edema, hemorrhaging, and late stage embryonic lethality. In endothelial cells, we find that Ena/VASP activity is required for normal F-actin content, actomyosin contractility, and proper response to shear stress. These findings demonstrate that Ena/VASP is critical for actin cytoskeleton remodeling events involved in the maintenance of functional endothelia.

Furman, Craig; Sieminski, Alisha L.; Kwiatkowski, Adam V.; Rubinson, Douglas A.; Vasile, Eliza; Bronson, Roderick T.; Fassler, Reinhard; Gertler, Frank B.

2007-01-01

172

The archetypal R90C CADASIL-NOTCH3 mutation retains NOTCH3 function in vivo.  

PubMed

Cerebral Autosomal Dominant Arteriopathy with Subcortical infarcts and Leukoencephalopathy (CADASIL) is the most prominent known cause of inherited stroke and vascular dementia in human adult. The disease gene, NOTCH3, encodes a transmembrane receptor primarily expressed in arterial smooth muscle cells (SMC). Pathogenic mutations lead to an odd number of cysteine residues within the NOTCH3 extracellular domain (NOTCH3(ECD)), and are associated with progressive accumulation of NOTCH3(ECD) at the SMC plasma membrane. The murine homolog, Notch3, is dispensable for viability but required post-natally for the elaboration and maintenance of arteries. How CADASIL-associated mutations impact NOTCH3 function remains a fundamental, yet unresolved issue. Particularly, whether NOTCH3(ECD) accumulation may titrate the ligand and inhibit the normal pathway is unknown. Herein, using genetic analyses in the mouse, we assessed the functional significance of an archetypal CADASIL-associated mutation (R90C), in vivo, in brain arteries. We show that transgenic mouse lines expressing either the wild-type human NOTCH3 or the mutant R90C human NOTCH3, at comparable and physiological levels, can rescue the arterial defects of Notch3-/- mice to similar degrees. In vivo assessment of NOTCH3/RBP-Jk activity provides evidence that the mutant NOTCH3 protein exhibits normal level of activity in brain arteries. Remarkably, the mutant NOTCH3 protein remains functional and does not exhibit dominant negative interfering activity, even when NOTCH3(ECD) accumulates. Collectively, these data suggest a model that invokes novel pathogenic roles for the mutant NOTCH3 protein rather than compromised NOTCH3 function as the primary determinant of the CADASIL arteriopathy. PMID:17331978

Monet, Marie; Domenga, Valérie; Lemaire, Barbara; Souilhol, Céline; Langa, Francina; Babinet, Charles; Gridley, Thomas; Tournier-Lasserve, Elisabeth; Cohen-Tannoudji, Michel; Joutel, Anne

2007-03-01

173

Administration of single-dose GnRH agonist in the luteal phase in ICSI cycles: a meta-analysis  

Microsoft Academic Search

BACKGROUND: The effects of gonadotrophin-releasing hormone agonist (GnRH-a) administered in the luteal phase remains controversial. This meta-analysis aimed to evaluate the effect of the administration of a single-dose of GnRH-a in the luteal phase on ICSI clinical outcomes. METHODS: The research strategy included the online search of databases. Only randomized studies were included. The outcomes analyzed were implantation rate, clinical

João Batista A Oliveira; Ricardo Baruffi; Cláudia G Petersen; Ana L Mauri; Mario Cavagna; José G Franco Jr

2010-01-01

174

Selective early elimination of luteal support in assisted reproduction cycles using a gonadotropin-releasing hormone agonist during ovarian stimulation  

Microsoft Academic Search

Objective: To determine if women undergoing GnRH agonist-hMG stimulated IVF cycles can undergo successful discontinuation of luteal phase support.Design: A protocol for selective discontinuation of luteal phase support was evaluated prospectively in women undergoing assisted reproduction cycles.Setting: A tertiary care institutional-based assisted reproduction program.Patient(s): One hundred eighty-eight women who conceived after an IVF or zygote intrafallopian transfer cycle including a

Dale W Stovall; Bradley J Van Voorhis; Amy E. T Sparks; Laura M Adams; Craig H Syrop

1998-01-01

175

Synaptic Structure and Function in the Mouse Somatosensory Cortex during Chronic Pain: In Vivo Two-Photon Imaging  

PubMed Central

Recent advances in two-photon microscopy and fluorescence labeling techniques have enabled us to directly see the structural and functional changes in neurons and glia, and even at synapses, in the brain of living animals. Long-term in vivo two-photon imaging studies have shown that some postsynaptic dendritic spines in the adult cortex are rapidly eliminated or newly generated, in response to altered sensory input or synaptic activity, resulting in experience/activity-dependent rewiring of neuronal circuits. In vivo Ca2+ imaging studies have revealed the distinct, input-specific response patterns of excitatory neurons in the brain. These updated in vivo approaches are just beginning to be used for the study of pathophysiological mechanisms of chronic diseases. In this paper, we introduce recent in vivo two-photon imaging studies demonstrating how plastic changes in synaptic structure and function of the mouse somatosensory cortex, following peripheral injury, contribute to chronic pain conditions, like neuropathic and inflammatory pain.

Kim, Sun Kwang; Eto, Kei; Nabekura, Junichi

2012-01-01

176

Mapping 3-D functional capillary geometry in rat skeletal muscle in vivo  

PubMed Central

We have developed a novel mapping software package to reconstruct microvascular networks in three dimensions (3-D) from in vivo video images for use in blood flow and O2 transport modeling. An intravital optical imaging system was used to collect video sequences of blood flow in microvessels at different depths in the tissue. Functional images of vessels were produced from the video sequences and were processed using automated edge tracking software to yield location and geometry data for construction of the 3-D network. The same video sequences were analyzed for hemodynamic and O2 saturation data from individual capillaries in the network. Simple user-driven commands allowed the connection of vessel segments at bifurcations, and semiautomated registration enabled the tracking of vessels across multiple focal planes and fields of view. The reconstructed networks can be rotated and manipulated in 3-D to verify vessel connections and continuity. Hemodynamic and O2 saturation measurements made in vivo can be indexed to corresponding vessels and visualized using colorized maps of the vascular geometry. Vessels in each reconstruction are saved as text-based files that can be easily imported into flow or O2 transport models with complete geometry, hemodynamic, and O2 transport conditions. The results of digital morphometric analysis of seven microvascular networks showed mean capillary diameters and overall capillary density consistent with previous findings using histology and corrosion cast techniques. The described mapping software is a valuable tool for the quantification of in vivo microvascular geometry, hemodynamics, and oxygenation, thus providing rich data sets for experiment-based computational models.

Milkovich, Stephanie; Goldman, Daniel; Ellis, Christopher G.

2012-01-01

177

Characterization of the structural and functional determinants of MANF/CDNF in Drosophila in vivo model.  

PubMed

Mammalian MANF and CDNF proteins are evolutionarily conserved neurotrophic factors that can protect and repair mammalian dopaminergic neurons in vivo. In Drosophila, the sole MANF protein (DmManf) is needed for the maintenance of dopaminergic neurites and dopamine levels. Although both secreted and intracellular roles for MANF and CDNF have been demonstrated, very little is known about the molecular mechanism of their action. Here, by using a transgenic rescue approach in the DmManf mutant background we show that only full-length MANF containing both the amino-terminal saposin-like and carboxy-terminal SAP-domains can rescue the larval lethality of the DmManf mutant. Independent N- or C-terminal domains of MANF, even when co-expressed together, fail to rescue. Deleting the signal peptide or mutating the CXXC motif in the C-terminal domain destroys the activity of full-length DmManf. Positively charged surface amino acids and the C-terminal endoplasmic reticulum retention signal are necessary for rescue of DmManf mutant lethality when DmManf is expressed in a restricted pattern. Furthermore, rescue experiments with non-ubiquitous expression reveals functional differences between the C-terminal domain of human MANF and CDNF. Finally, DmManf and its C-terminal domain rescue mammalian sympathetic neurons from toxin-induced apoptosis in vitro demonstrating functional similarity of the mammalian and fly proteins. Our study offers further insights into the functional conservation between invertebrate and mammalian MANF/CDNF proteins and reveals the importance of the C-terminal domain for MANF activity in vivo. PMID:24019940

Lindström, Riitta; Lindholm, Päivi; Kallijärvi, Jukka; Yu, Li-Ying; Piepponen, T Petteri; Arumäe, Urmas; Saarma, Mart; Heino, Tapio I

2013-09-03

178

Estrogen protects renal endothelial barrier function from ischemia-reperfusion in vitro and in vivo.  

PubMed

Emerging evidence suggests that renal endothelial function may be altered in ischemia-reperfusion injury. Acute kidney injury is sexually dimorphic, and estrogen protects renal tubular function after experimental ischemic injury. This study tested the hypothesis that during ischemia-reperfusion, estrogen alters glomerular endothelial function to prevent hyperpermeability. Glomerular endothelial cells were exposed to 8-h oxygen-glucose deprivation (OGD) followed by 4- and 8-h reoxygenation-glucose repletion. After 4-h reoxygenation-glucose repletion, transendothelial permeability to Ficoll-70 was reduced, and transendothelial resistance increased, by 17?-estradiol vs. vehicle treatment during OGD (OGD-vehicle: 91.0 ± 11.8%, OGD-estrogen: 102.6 ± 10.8%, P < 0.05). This effect was reversed by coadministration of G protein-coupled receptor 30 (GPR30) antagonist G15 with 17?-estradiol (OGD-estrogen-G15: 89.5 ± 6.9, P < 0.05 compared with 17?-estradiol). To provide preliminary confirmation of this result in vivo, Ficoll-70 was administered to mice 24 h after cardiac arrest and cardiopulmonary resuscitation (CA/CPR). Blood urea nitrogen (BUN) and serum creatinine (SCr) in these mice were elevated within 12 h following CA/CPR and reduced at 24 h by pretreatment with 17?-estradiol (BUN/SCr 17?-estradiol: 34 ± 19/0.2 ± 0.1 vehicle: 92 ± 49/0.5 ± 0.3, n = 8-12, P < 0.05). Glomerular sieving of Ficoll 70 was increased by CA/CPR within 2 h of injury and 17?-estradiol treatment (?; 17?-estradiol: 0.74 ± 0.26 vs. vehicle: 1.05 ± 0.53, n = 14-15, P < 0.05). These results suggest that estrogen reduces postischemic glomerular endothelial hyperpermeability at least in part through GPR30 and that estrogen may regulate post CA/CPR glomerular permeability in a similar fashion in vivo. PMID:22622457

Hutchens, Michael P; Fujiyoshi, Tetsuhiro; Komers, Radko; Herson, Paco S; Anderson, Sharon

2012-05-23

179

Estrogen protects renal endothelial barrier function from ischemia-reperfusion in vitro and in vivo  

PubMed Central

Emerging evidence suggests that renal endothelial function may be altered in ischemia-reperfusion injury. Acute kidney injury is sexually dimorphic, and estrogen protects renal tubular function after experimental ischemic injury. This study tested the hypothesis that during ischemia-reperfusion, estrogen alters glomerular endothelial function to prevent hyperpermeability. Glomerular endothelial cells were exposed to 8-h oxygen-glucose deprivation (OGD) followed by 4- and 8-h reoxygenation-glucose repletion. After 4-h reoxygenation-glucose repletion, transendothelial permeability to Ficoll-70 was reduced, and transendothelial resistance increased, by 17?-estradiol vs. vehicle treatment during OGD (OGD-vehicle: 91.0 ± 11.8%, OGD-estrogen: 102.6 ± 10.8%, P < 0.05). This effect was reversed by coadministration of G protein-coupled receptor 30 (GPR30) antagonist G15 with 17?-estradiol (OGD-estrogen-G15: 89.5 ± 6.9, P < 0.05 compared with 17?-estradiol). To provide preliminary confirmation of this result in vivo, Ficoll-70 was administered to mice 24 h after cardiac arrest and cardiopulmonary resuscitation (CA/CPR). Blood urea nitrogen (BUN) and serum creatinine (SCr) in these mice were elevated within 12 h following CA/CPR and reduced at 24 h by pretreatment with 17?-estradiol (BUN/SCr 17?-estradiol: 34 ± 19/0.2 ± 0.1 vehicle: 92 ± 49/0.5 ± 0.3, n = 8–12, P < 0.05). Glomerular sieving of Ficoll 70 was increased by CA/CPR within 2 h of injury and 17?-estradiol treatment (?; 17?-estradiol: 0.74 ± 0.26 vs. vehicle: 1.05 ± 0.53, n = 14–15, P < 0.05). These results suggest that estrogen reduces postischemic glomerular endothelial hyperpermeability at least in part through GPR30 and that estrogen may regulate post CA/CPR glomerular permeability in a similar fashion in vivo.

Fujiyoshi, Tetsuhiro; Komers, Radko; Herson, Paco S.; Anderson, Sharon

2012-01-01

180

Exoribonuclease and endoribonuclease activities of RNase BN/RNase Z both function in vivo.  

PubMed

Escherichia coli RNase BN, a member of the RNase Z family of endoribonucleases, differs from other family members in that it also can act as an exoribonuclease in vitro. Here, we examine whether this activity of RNase BN also functions in vivo. Comparison of the x-ray structure of RNase BN with that of Bacillus subtilis RNase Z, which lacks exoribonuclease activity, revealed that RNase BN has a narrower and more rigid channel downstream of the catalytic site. We hypothesized that this difference in the putative RNA exit channel might be responsible for the acquisition of exoribonuclease activity by RNase BN. Accordingly, we generated several mutant RNase BN proteins in which residues within a loop in this channel were converted to the corresponding residues present in B. subtilis RNase Z, thus widening the channel and increasing its flexibility. The resulting mutant RNase BN proteins had reduced or were essentially devoid of exoribonuclease activity in vitro. Substitution of one mutant rbn gene (P142G) for wild type rbn in the E. coli chromosome revealed that the exoribonuclease activity of RNase BN is not required for maturation of phage T4 tRNA precursors, a known specific function of this RNase. On the other hand, removal of the exoribonuclease activity of RNase BN in a cell lacking other processing RNases leads to slower growth and affects maturation of multiple tRNA precursors. These findings help explain how RNase BN can act as both an exo- and an endoribonuclease and also demonstrate that its exoribonuclease activity is capable of functioning in vivo, thus widening the potential role of this enzyme in E. coli. PMID:22893707

Dutta, Tanmay; Malhotra, Arun; Deutscher, Murray P

2012-08-14

181

Exoribonuclease and Endoribonuclease Activities of RNase BN/RNase Z both Function in Vivo*  

PubMed Central

Escherichia coli RNase BN, a member of the RNase Z family of endoribonucleases, differs from other family members in that it also can act as an exoribonuclease in vitro. Here, we examine whether this activity of RNase BN also functions in vivo. Comparison of the x-ray structure of RNase BN with that of Bacillus subtilis RNase Z, which lacks exoribonuclease activity, revealed that RNase BN has a narrower and more rigid channel downstream of the catalytic site. We hypothesized that this difference in the putative RNA exit channel might be responsible for the acquisition of exoribonuclease activity by RNase BN. Accordingly, we generated several mutant RNase BN proteins in which residues within a loop in this channel were converted to the corresponding residues present in B. subtilis RNase Z, thus widening the channel and increasing its flexibility. The resulting mutant RNase BN proteins had reduced or were essentially devoid of exoribonuclease activity in vitro. Substitution of one mutant rbn gene (P142G) for wild type rbn in the E. coli chromosome revealed that the exoribonuclease activity of RNase BN is not required for maturation of phage T4 tRNA precursors, a known specific function of this RNase. On the other hand, removal of the exoribonuclease activity of RNase BN in a cell lacking other processing RNases leads to slower growth and affects maturation of multiple tRNA precursors. These findings help explain how RNase BN can act as both an exo- and an endoribonuclease and also demonstrate that its exoribonuclease activity is capable of functioning in vivo, thus widening the potential role of this enzyme in E. coli.

Dutta, Tanmay; Malhotra, Arun; Deutscher, Murray P.

2012-01-01

182

The putative cannabinoid receptor GPR55 affects osteoclast function in vitro and bone mass in vivo.  

PubMed

GPR55 is a G protein-coupled receptor recently shown to be activated by certain cannabinoids and by lysophosphatidylinositol (LPI). However, the physiological role of GPR55 remains unknown. Given the recent finding that the cannabinoid receptors CB(1) and CB(2) affect bone metabolism, we examined the role of GPR55 in bone biology. GPR55 was expressed in human and mouse osteoclasts and osteoblasts; expression was higher in human osteoclasts than in macrophage progenitors. Although the GPR55 agonists O-1602 and LPI inhibited mouse osteoclast formation in vitro, these ligands stimulated mouse and human osteoclast polarization and resorption in vitro and caused activation of Rho and ERK1/2. These stimulatory effects on osteoclast function were attenuated in osteoclasts generated from GPR55(-/-) macrophages and by the GPR55 antagonist cannabidiol (CBD). Furthermore, treatment of mice with this non-psychoactive constituent of cannabis significantly reduced bone resorption in vivo. Consistent with the ability of GPR55 to suppress osteoclast formation but stimulate osteoclast function, histomorphometric and microcomputed tomographic analysis of the long bones from male GPR55(-/-) mice revealed increased numbers of morphologically inactive osteoclasts but a significant increase in the volume and thickness of trabecular bone and the presence of unresorbed cartilage. These data reveal a role of GPR55 in bone physiology by regulating osteoclast number and function. In addition, this study also brings to light an effect of both the endogenous ligand, LPI, on osteoclasts and of the cannabis constituent, CBD, on osteoclasts and bone turnover in vivo. PMID:19805329

Whyte, Lauren S; Ryberg, Erik; Sims, Natalie A; Ridge, Susan A; Mackie, Ken; Greasley, Peter J; Ross, Ruth A; Rogers, Michael J

2009-09-03

183

The putative cannabinoid receptor GPR55 affects osteoclast function in vitro and bone mass in vivo  

PubMed Central

GPR55 is a G protein-coupled receptor recently shown to be activated by certain cannabinoids and by lysophosphatidylinositol (LPI). However, the physiological role of GPR55 remains unknown. Given the recent finding that the cannabinoid receptors CB1 and CB2 affect bone metabolism, we examined the role of GPR55 in bone biology. GPR55 was expressed in human and mouse osteoclasts and osteoblasts; expression was higher in human osteoclasts than in macrophage progenitors. Although the GPR55 agonists O-1602 and LPI inhibited mouse osteoclast formation in vitro, these ligands stimulated mouse and human osteoclast polarization and resorption in vitro and caused activation of Rho and ERK1/2. These stimulatory effects on osteoclast function were attenuated in osteoclasts generated from GPR55?/? macrophages and by the GPR55 antagonist cannabidiol (CBD). Furthermore, treatment of mice with this non-psychoactive constituent of cannabis significantly reduced bone resorption in vivo. Consistent with the ability of GPR55 to suppress osteoclast formation but stimulate osteoclast function, histomorphometric and microcomputed tomographic analysis of the long bones from male GPR55?/? mice revealed increased numbers of morphologically inactive osteoclasts but a significant increase in the volume and thickness of trabecular bone and the presence of unresorbed cartilage. These data reveal a role of GPR55 in bone physiology by regulating osteoclast number and function. In addition, this study also brings to light an effect of both the endogenous ligand, LPI, on osteoclasts and of the cannabis constituent, CBD, on osteoclasts and bone turnover in vivo.

Whyte, Lauren S.; Ryberg, Erik; Sims, Natalie A.; Ridge, Susan A.; Mackie, Ken; Greasley, Peter J.; Ross, Ruth A.; Rogers, Michael J.

2009-01-01

184

Characterization of the Structural and Functional Determinants of MANF/CDNF in Drosophila In Vivo Model  

PubMed Central

Mammalian MANF and CDNF proteins are evolutionarily conserved neurotrophic factors that can protect and repair mammalian dopaminergic neurons in vivo. In Drosophila, the sole MANF protein (DmManf) is needed for the maintenance of dopaminergic neurites and dopamine levels. Although both secreted and intracellular roles for MANF and CDNF have been demonstrated, very little is known about the molecular mechanism of their action. Here, by using a transgenic rescue approach in the DmManf mutant background we show that only full-length MANF containing both the amino-terminal saposin-like and carboxy-terminal SAP-domains can rescue the larval lethality of the DmManf mutant. Independent N- or C-terminal domains of MANF, even when co-expressed together, fail to rescue. Deleting the signal peptide or mutating the CXXC motif in the C-terminal domain destroys the activity of full-length DmManf. Positively charged surface amino acids and the C-terminal endoplasmic reticulum retention signal are necessary for rescue of DmManf mutant lethality when DmManf is expressed in a restricted pattern. Furthermore, rescue experiments with non-ubiquitous expression reveals functional differences between the C-terminal domain of human MANF and CDNF. Finally, DmManf and its C-terminal domain rescue mammalian sympathetic neurons from toxin-induced apoptosis in vitro demonstrating functional similarity of the mammalian and fly proteins. Our study offers further insights into the functional conservation between invertebrate and mammalian MANF/CDNF proteins and reveals the importance of the C-terminal domain for MANF activity in vivo.

Lindstrom, Riitta; Lindholm, Paivi; Kallijarvi, Jukka; Yu, Li-ying; Piepponen, T. Petteri; Arumae, Urmas; Saarma, Mart; Heino, Tapio I.

2013-01-01

185

Equine chorionic gonadotropin alters luteal cell morphologic features related to progesterone synthesis.  

PubMed

Exogenous eCG for stimulation of a single dominant follicle or for superovulation are common strategies to improve reproductive efficiency by increasing pregnancy rates and embryo production, respectively. Morphofunctional changes in the CL of eCG-treated cattle include increases in CL volume and plasma progesterone concentrations. Therefore, we tested the hypothesis that eCG alters the content of luteal cells and mitochondria related to hormone production. Twelve crossbred beef cows were synchronized and then allocated into three groups (four cows per group) and received no further treatment (control) or were given eCG either before or after follicular deviation (superovulation and stimulation of the dominant follicle, respectively). Six days after ovulation, cows were slaughtered and CL collected for morphohistologic and ultrastructural analysis. Mitochondrial volume per CL was highest in superovulated followed by stimulated and then control cows (18,500 ± 2630, 12,300 ± 2640, and 7670 ± 3400 ?m(3); P < 0.001), and the density of spherical mitochondria and the total number of large luteal cells were increased (P < 0.05) in stimulated cows compared with the other two groups (110.32 ± 14.22, 72.26 ± 8.77, and 70.46 ± 9.58 mitochondria per ?m(3) and 678 ± 147, 245 ± 199, and 346 ± 38 × 10(6) cells, respectively. However, the largest diameters of the large luteal cells were increased in superovulated and control cows versus stimulated ones (32.32 ± 0.06, 31.59 ± 0.81, and 29.44 ± 0.77 ?m; P < 0.0001). In contrast, the total number of small luteal cells was increased in superovulated cows (1456 ± 268, 492 ± 181, and 822 ± 461 × 10(6), P < 0.05). In conclusion, there were indications of cellular changes related to increased hormonal production (stimulatory treatment) and increased CL volume (superovulatory treatment). PMID:23273432

Rigoglio, Nathia N; Fátima, Luciana A; Hanassaka, Jaqueline Y; Pinto, Gizélia L; Machado, Alex S D; Gimenes, Lindsay U; Baruselli, Pietro S; Rennó, Francisco P; Moura, Carlos E B; Watanabe, Il-Sei; Papa, Paula C

2012-12-27

186

Achievement of pregnancy three times in the same patient during luteal GnRH agonist administration  

Microsoft Academic Search

Gonadotrophin-releasing hormone agonist (GnRHa) administration from the mid-luteal phase onwards is considered the gold standard of ovarian stimulation for IVF treatment. It might, however, coincide with an implanting spontaneous pregnancy. Concerns have therefore been raised with regard to the evolution of the resulting pregnancies and long-term outcome of the children born. The current case report describes the achievement of three

Evangelos G Papanikolaou; Peter Platteau; Carola Albano; Efstratios Kolibianakis; Paul Devroey

2005-01-01

187

Randomized controlled pilot trial of luteal phase recombinant FSH stimulation in poor responders  

Microsoft Academic Search

This study investigated whether luteal phase initiation of FSH supplementation would improve oocyte yield compared with follicular phase administration in women with poor ovarian response (POR). A two-arm, randomized, open-label pilot trial was performed at a university-based infertility centre. In nine of 18 infertile women with a history of POR in a previous cycle [10 mm and >16 mm and

Suleena Kansal Kalra; Sarah Ratcliffe; Clarisa R Gracia; Linda Martino; Christos Coutifaris; Kurt T Barnhart

2008-01-01

188

Increase of Progesterone Production in Human and Rat Luteal Cells by Beta-Adrenergic Stimulation  

Microsoft Academic Search

The effects of the ?2-adrenergic agonist hexoprenaline were studied on the progesterone production of rat and human corpora lutea and compared to hCG-induced hormone production. Human corpora lutea were obtained from healthy patients, rat corpora lutea were harvested on day 6 of pseudopregnancy. Corpora lutea were digested by trypsin and homogeneous luteal cell suspension (6 × 105 cells\\/ml) was incubated

Bertalan Varga; Béla Zsolnai; Ervin Stark

1987-01-01

189

MS-based metabolomics facilitates the discovery of in vivo functional small molecules with a diversity of biological contexts.  

PubMed

In vivo small molecules as necessary intermediates are involved in numerous critical metabolic pathways and biological processes associated with many essential biological functions and events. There is growing evidence that MS-based metabolomics is emerging as a powerful tool to facilitate the discovery of functional small molecules that can better our understanding of development, infection, nutrition, disease, toxicity, drug therapeutics, gene modifications and host-pathogen interaction from metabolic perspectives. However, further progress must still be made in MS-based metabolomics because of the shortcomings in the current technologies and knowledge. This technique-driven review aims to explore the discovery of in vivo functional small molecules facilitated by MS-based metabolomics and to highlight the analytic capabilities and promising applications of this discovery strategy. Moreover, the biological significance of the discovery of in vivo functional small molecules with different biological contexts is also interrogated at a metabolic perspective. PMID:24175746

Yan, Leyu; Nie, Wenna; Parker, Tony; Upton, Zee; Lu, Haitao

2013-10-01

190

Elevation of transcription factor Islet-1 levels in vivo increases ?-cell function but not ?-cell mass.  

PubMed

A decrease in the expression of Islet-1 (Isl-1), an islet transcription factor, has been reported in several physiological settings of reduced ?-cell function. Here, we investigate whether an increased level of Isl-1 in islet cells can enhance ?-cell function and/or mass. We demonstrate that transgenic mice with Isl-1 overexpression display improved glucose tolerance and enhanced insulin secretion without significant changes in ? cell mass. From our microarray study, we identify approximately 135 differentially expressed genes in the islets of Isl-1 overexpressing mice that have been implicated to function in numerous biological processes including protein trafficking, metabolism and differentiation. Using real-time PCR we have confirmed upregulation of Caps2, Sec14l4, Slc2a10, P2rx7, Afamin, and Neurogenin 3 that may in part mediate the observed improved insulin secretion in Isl-1 overexpressing mice. These findings show for the first time that Isl-1 is a key factor in regulating adult ? cell function in vivo, and suggest that Isl-1 elevation could be beneficial to improve glucose homeostasis. PMID:22595886

Liu, Jingxuan; Walp, Erik R; May, Catherine Lee

2012-05-01

191

Imaging the Function of P-Glycoprotein With Radiotracers: Pharmacokinetics and In Vivo Applications  

PubMed Central

P-glycoprotein (P-gp), an efflux transporter, controls the pharmacokinetics of various compounds under physiological conditions. P-gp-mediated drug efflux has been suggested as playing a role in various disorders, including multidrug-resistant cancer and medication-refractory epilepsy. However, P-gp inhibition has had, to date, little or no clinically significant effect in multidrug-resistant cancer. To enhance our understanding of its in vivo function under pathophysiological conditions, substrates of P-gp have been radiolabeled and imaged using single-photon emission computed tomography (SPECT) and positron emission tomography (PET). To accurately quantify P-gp function, a radiolabeled P-gp substrate should be selective for P-gp, produce a large signal after P-gp blockade, and generate few radiometabolites that enter the target tissue. Furthermore, quantification of P-gp function via imaging requires pharmacological inhibition of P-gp, which requires knowledge of P-gp density at the target site. By meeting these criteria, imaging can elucidate the function of P-gp in various disorders and improve the efficacy of treatments.

Kannan, P; John, C; Zoghbi, SS; Halldin, C; Gottesman, MM; Innis, RB; Hall, MD

2009-01-01

192

A simplified serum-free method for preparation and cultivation of human granulosa-luteal cells.  

PubMed

A simplified method for the preparation and long-term cultivation of granulosa-luteal cells in serum-free medium is described. The cells were harvested from women undergoing in-vitro fertilization, enriched by sedimentation and dissociated by enzymatic treatment. We demonstrated, by introducing a synthetic serum replacement (SSR2), that these primary cell cultures cultivated in monolayers on an extracellular matrix may be used in experiments exceeding 7 days with low cell loss and cell death. No adverse effect on progesterone production was found. There was a high diversity in progesterone production between cells from individual patients. After several days in culture, the cells were challenged with human chorionic gonadotrophin which revived the rapidly decreasing progesterone production. We were unable to demonstrate an increase in cell number after 7 days of cultivation when the cells were grown in medium supplemented with either serum or SSR2. The mitogens epidermal growth factor and basic fibroblast growth factor had no influence on proliferation. We also found that the present method prevents leukocyte contamination in the granulosa-luteal cell cultures. Compared with the common method based on the enrichment of granulosa-luteal cells on a density gradient (Ficoll/Percoll), this method saves time, labour and expense, in addition to augmenting purity. PMID:9130754

Figenschau, Y; Sundsfjord, J A; Yousef, M I; Fuskevåg, O M; Sveinbjörnsson, B; Bertheussen, K

1997-03-01

193

Cellular in vivo imaging reveals coordinated regulation of pituitary microcirculation and GH cell network function.  

PubMed

Growth hormone (GH) exerts its actions via coordinated pulsatile secretion from a GH cell network into the bloodstream. Practically nothing is known about how the network receives its inputs in vivo and releases hormones into pituitary capillaries to shape GH pulses. Here we have developed in vivo approaches to measure local blood flow, oxygen partial pressure, and cell activity at single-cell resolution in mouse pituitary glands in situ. When secretagogue (GHRH) distribution was modeled with fluorescent markers injected into either the bloodstream or the nearby intercapillary space, a restricted distribution gradient evolved within the pituitary parenchyma. Injection of GHRH led to stimulation of both GH cell network activities and GH secretion, which was temporally associated with increases in blood flow rates and oxygen supply by capillaries, as well as oxygen consumption. Moreover, we observed a time-limiting step for hormone output at the perivascular level; macromolecules injected into the extracellular parenchyma moved rapidly to the perivascular space, but were then cleared more slowly in a size-dependent manner into capillary blood. Our findings suggest that GH pulse generation is not simply a GH cell network response, but is shaped by a tissue microenvironment context involving a functional association between the GH cell network activity and fluid microcirculation. PMID:20160103

Lafont, Chrystel; Desarménien, Michel G; Cassou, Mathieu; Molino, François; Lecoq, Jérôme; Hodson, David; Lacampagne, Alain; Mennessier, Gérard; El Yandouzi, Taoufik; Carmignac, Danielle; Fontanaud, Pierre; Christian, Helen; Coutry, Nathalie; Fernandez-Fuente, Marta; Charpak, Serge; Le Tissier, Paul; Robinson, Iain C A F; Mollard, Patrice

2010-02-16

194

Characterization of antisera against bovine prolactin for in vivo studies on prolactin function in the rat.  

PubMed Central

The IgG fraction of rabbit antisera to bovine prolactin (PRL), intended for in vivo studies on the role of PRL in the rat, was prepared and characterized in vitro and in vivo. The antibodies showed a strong reaction with bovine PRL in double diffusion, immunoelectrophoresis, radioimmunoassay and passive haemagglutination using bovine PRL-coated erythrocytes. In indirect immunofluorescence on paraffin sections of bovine pituitary glands the antibodies could be used for the detection of PRL-producing cells. Cross-reaction with rat PRL was observed in passive haemagglutination with rat PRL-coated erythrocytes and in indirect immunofluorescence on rat pituitary gland, but not in any of the other test systems. The ability of the antibodies to neutralize homologous, i.e. bovine, PRL was tested in lactating rats depleted of endogenous PRL by bromergocriptin treatment. The impaired lactation performance of such animals can be restored by substitution with bovine PRL. If the bovine PRL used for substitution was complexed with anti-bovine PRL-IgG, it lost its biological activity. On the other hand, injections of even high amounts of the antibodies into lactating rats failed to reveal any effect on lactation. It is concluded that either the antibodies do not cross-react with circulating rat PRL in contrast to pituitary PRL (preprolactin?) or that the cross-reacting antibody-populations(s) lack(s) the ability to neutralize the biological function of rat PRL.

Kofler, R; Tabarelli, M; Schwarz, S; Wolf, H; Loewit, K; Wick, G

1980-01-01

195

In vitro hematological and in vivo vasoactivity assessment of dextran functionalized graphene.  

PubMed

The intravenous, intramuscular or intraperitoneal administration of water solubilized graphene nanoparticles for biomedical applications will result in their interaction with the hematological components and vasculature. Herein, we have investigated the effects of dextran functionalized graphene nanoplatelets (GNP-Dex) on histamine release, platelet activation, immune activation, blood cell hemolysis in vitro, and vasoactivity in vivo. The results indicate that GNP-Dex formulations prevented histamine release from activated RBL-2H3 rat mast cells, and at concentrations ? 7?mg/ml, showed a 12-20% increase in levels of complement proteins. Cytokine (TNF-Alpha and IL-10) levels remained within normal range. GNP-Dex formulations did not cause platelet activation or blood cell hemolysis. Using the hamster cheek pouch in vivo model, the initial vasoactivity of GNP-Dex at concentrations (1-50?mg/ml) equivalent to the first pass of a bolus injection was a brief concentration-dependent dilation in arcade and terminal arterioles. However, they did not induce a pro-inflammatory endothelial dysfunction effect. PMID:24002570

Chowdhury, Sayan Mullick; Kanakia, Shruti; Toussaint, Jimmy D; Frame, Mary D; Dewar, Anthony M; Shroyer, Kenneth R; Moore, William; Sitharaman, Balaji

2013-09-01

196

In Vivo Evaluation of Vena Caval Filters: Can Function Be Linked to Design Characteristics?  

SciTech Connect

Purpose: To compare the five vena caval filters marketed in the United States and one investigational vena caval filter and to determine whether there is an association between their design and their in vivo function.Methods: Four of each type of filter-Simon Nitinol (SN), Bird's Nest (BN), Vena Tech (VT), Greenfield stainless steel (PSGF), Greenfield titanium (TGF), and the investigational stent cone filter (NGF)-were studied for 60 days in 12 sheep. Radiographic and pathologic outcomes to be assessed included clot capture and resolution, vena caval penetration, position of the filter, thrombogenicity, and vessel wall reaction.Results: Filters differed with respect to the number of clot-trapping levels and the interdependence of the legs. All devices were successfully placed. Intentionally embolized clot was captured. One VT and two SN filters migrated in response to clot capture. Resolution of thrombus was variable, and related to the design of the device. Fibrin webbing was widely present with the VT, BN, and SN filters but limited in the others. The VT and NGF filters demonstrated the most stable filter base diameter.Conclusions: The performance of vena caval filters differs with respect to clot resolution and mechanical stability. Interdependent filter limbs and single-stage conical capture sites appear to result in more favorable performance in in vivo studies.

Proctor, Mary C. [Department of Surgery, University of Michigan Hospitals, 1500 East Medical Center Drive, Ann Arbor, MI 48109-0346 (United States); Cho, Kyung J. [Department of Radiology, University of Michigan Hospitals, 1500 East Medical Center Drive, Ann Arbor, MI 48109-0346 (United States); Greenfield, Lazar J. [Department of Surgery, University of Michigan Hospitals, 1500 East Medical Center Drive, Ann Arbor, MI 48109-0346 (United States)

2000-11-15

197

Selective ex-vivo photothermal ablation of human pancreatic cancer with albumin functionalized multiwalled carbon nanotubes  

PubMed Central

The process of laser-mediated ablation of cancer cells marked with biofunctionalized carbon nanotubes is frequently called “nanophotothermolysis”. We herein present a method of selective nanophotothermolisys of pancreatic cancer (PC) using multiwalled carbon nanotubes (MWCNTs) functionalized with human serum albumin (HSA). With the purpose of testing the therapeutic value of these nanobioconjugates, we have developed an ex-vivo experimental platform. Surgically resected specimens from patients with PC were preserved in a cold medium and kept alive via intra-arterial perfusion. Additionally, the HSA-MWCNTs have been intra-arterially administered in the greater pancreatic artery under ultrasound guidance. Confocal and transmission electron microscopy combined with immunohistochemical staining have confirmed the selective accumulation of HSA-MWCNTs inside the human PC tissue. The external laser irradiation of the specimen has significantly produced extensive necrosis of the malign tissue after the intra-arterial administration of HSA-MWCNTs, without any harmful effects on the surrounding healthy parenchyma. We have obtained a selective photothermal ablation of the malign tissue based on the selective internalization of MWCNTs with HSA cargo inside the pancreatic adenocarcinoma after the ex-vivo intra-arterial perfusion.

Mocan, Lucian; Tabaran, Flaviu A; Mocan, Teodora; Bele, Constantin; Orza, Anamaria Ioana; Lucan, Ciprian; Stiufiuc, Rares; Manaila, Ioana; Iulia, Ferencz; Dana, Iancu; Zaharie, Florin; Osian, Gelu; Vlad, Liviu; Iancu, Cornel

2011-01-01

198

Selective ex-vivo photothermal ablation of human pancreatic cancer with albumin functionalized multiwalled carbon nanotubes.  

PubMed

The process of laser-mediated ablation of cancer cells marked with biofunctionalized carbon nanotubes is frequently called "nanophotothermolysis". We herein present a method of selective nanophotothermolisys of pancreatic cancer (PC) using multiwalled carbon nanotubes (MWCNTs) functionalized with human serum albumin (HSA). With the purpose of testing the therapeutic value of these nanobioconjugates, we have developed an ex-vivo experimental platform. Surgically resected specimens from patients with PC were preserved in a cold medium and kept alive via intra-arterial perfusion. Additionally, the HSA-MWCNTs have been intra-arterially administered in the greater pancreatic artery under ultrasound guidance. Confocal and transmission electron microscopy combined with immunohistochemical staining have confirmed the selective accumulation of HSA-MWCNTs inside the human PC tissue. The external laser irradiation of the specimen has significantly produced extensive necrosis of the malign tissue after the intra-arterial administration of HSA-MWCNTs, without any harmful effects on the surrounding healthy parenchyma. We have obtained a selective photothermal ablation of the malign tissue based on the selective internalization of MWCNTs with HSA cargo inside the pancreatic adenocarcinoma after the ex-vivo intra-arterial perfusion. PMID:21720504

Mocan, Lucian; Tabaran, Flaviu A; Mocan, Teodora; Bele, Constantin; Orza, Anamaria Ioana; Lucan, Ciprian; Stiufiuc, Rares; Manaila, Ioana; Iulia, Ferencz; Dana, Iancu; Zaharie, Florin; Osian, Gelu; Vlad, Liviu; Iancu, Cornel

2011-04-28

199

The yeast centromere CDEI/Cpf1 complex: differences between in vitro binding and in vivo function.  

PubMed Central

The centromere and promoter factor Cpf1 binds centromere DNA element I found in all centromere DNAs from the yeast Saccharomyces cerevisiae. We analyzed thirty different point mutations in or around CEN6-CDEI (ATCACGTG) for their relative binding affinity to Cpf1 and these data were compared with the in vivo centromere function of these mutants. We show that the minimal length of the Cpf1 binding site needed for full in vitro binding and in vivo activity is 10 base pairs long comprised of CDEI plus the two base pairs 3' of this sequence. The palindromic core sequence CACGTG is most important for in vivo CEN function and in vitro Cpf1 binding. Symmetrical mutations in either halfsite of the core sequence affect in vitro Cpf1 binding and in vivo mitotic centromere function asymmetrically albeit to a different extent. Enlarging the CDEI palindrome to 12 or 20 bps increases in vitro Cpf1 binding but results in increased chromosome loss rates suggesting a need for asymmetrical Cpf1 binding sequences. Additionally, the ability of Cpf1 protein to bind a mutant CDEI element in vitro does not parallel the ability of that mutant to confer in vivo CEN activity. Our data indicate that the in vitro binding characteristics of Cpf1 to CDEI only partly overlap with their corresponding activity within the centromere complex, thus suggesting that in the in vivo situation the CDEI/Cpf1 complex might undergo interactions with other centromere DNA/protein complexes. Images

Wilmen, A; Pick, H; Niedenthal, R K; Sen-Gupta, M; Hegemann, J H

1994-01-01

200

The yeast centromere CDEI/Cpf1 complex: differences between in vitro binding and in vivo function.  

PubMed

The centromere and promoter factor Cpf1 binds centromere DNA element I found in all centromere DNAs from the yeast Saccharomyces cerevisiae. We analyzed thirty different point mutations in or around CEN6-CDEI (ATCACGTG) for their relative binding affinity to Cpf1 and these data were compared with the in vivo centromere function of these mutants. We show that the minimal length of the Cpf1 binding site needed for full in vitro binding and in vivo activity is 10 base pairs long comprised of CDEI plus the two base pairs 3' of this sequence. The palindromic core sequence CACGTG is most important for in vivo CEN function and in vitro Cpf1 binding. Symmetrical mutations in either halfsite of the core sequence affect in vitro Cpf1 binding and in vivo mitotic centromere function asymmetrically albeit to a different extent. Enlarging the CDEI palindrome to 12 or 20 bps increases in vitro Cpf1 binding but results in increased chromosome loss rates suggesting a need for asymmetrical Cpf1 binding sequences. Additionally, the ability of Cpf1 protein to bind a mutant CDEI element in vitro does not parallel the ability of that mutant to confer in vivo CEN activity. Our data indicate that the in vitro binding characteristics of Cpf1 to CDEI only partly overlap with their corresponding activity within the centromere complex, thus suggesting that in the in vivo situation the CDEI/Cpf1 complex might undergo interactions with other centromere DNA/protein complexes. PMID:8052535

Wilmen, A; Pick, H; Niedenthal, R K; Sen-Gupta, M; Hegemann, J H

1994-07-25

201

Molecular motor function in axonal transport in vivo probed by genetic and computational analysis in Drosophila  

PubMed Central

Bidirectional axonal transport driven by kinesin and dynein along microtubules is critical to neuronal viability and function. To evaluate axonal transport mechanisms, we developed a high-resolution imaging system to track the movement of amyloid precursor protein (APP) vesicles in Drosophila segmental nerve axons. Computational analyses of a large number of moving vesicles in defined genetic backgrounds with partial reduction or overexpression of motor proteins enabled us to test with high precision existing and new models of motor activity and coordination in vivo. We discovered several previously unknown features of vesicle movement, including a surprising dependence of anterograde APP vesicle movement velocity on the amount of kinesin-1. This finding is largely incompatible with the biophysical properties of kinesin-1 derived from in vitro analyses. Our data also suggest kinesin-1 and cytoplasmic dynein motors assemble in stable mixtures on APP vesicles and their direction and velocity are controlled at least in part by dynein intermediate chain.

Reis, Gerald F.; Yang, Ge; Szpankowski, Lukasz; Weaver, Carole; Shah, Sameer B.; Robinson, John T.; Hays, Thomas S.; Danuser, Gaudenz; Goldstein, Lawrence S. B.

2012-01-01

202

Biomimetic modification of metallic cardiovascular biomaterials: from function mimicking to endothelialization in vivo  

PubMed Central

Biosystem–surface interactions play an important role in various biological events and determine the ultimate functionality of implanted devices. Endothelialization or mimicking of endothelium on the surface of cardiovascular materials is a promising way to solve the problems of material-induced thrombosis and restenosis. Meanwhile, a multifunctional surface design is needed as antithrombotic properties should be considered in the period when the implants are not yet completely endothelialized. In this article, we summarize some successful approaches used in our laboratory for constructing multifunctional endothelium-like surfaces on metallic cardiovascular biomaterials through chemical modification of the surface or by the introduction of specific biological molecules to induce self-endothelialization in vivo. Some directions on future research in these areas are also presented.

Weng, Yajun; Chen, Junying; Tu, Qiufen; Li, Quanli; Maitz, Manfred F.; Huang, Nan

2012-01-01

203

In vivo neuronal function of the fragile X mental retardation protein is regulated by phosphorylation.  

PubMed

Fragile X syndrome (FXS), caused by loss of the Fragile X Mental Retardation 1 (FMR1) gene product (FMRP), is the most common heritable cause of intellectual disability and autism spectrum disorders. It has been long hypothesized that the phosphorylation of serine 500 (S500) in human FMRP controls its function as an RNA-binding translational repressor. To test this hypothesis in vivo, we employed neuronally targeted expression of three human FMR1 transgenes, including wild-type (hFMR1), dephosphomimetic (S500A-hFMR1) and phosphomimetic (S500D-hFMR1), in the Drosophila FXS disease model to investigate phosphorylation requirements. At the molecular level, dfmr1 null mutants exhibit elevated brain protein levels due to loss of translational repressor activity. This defect is rescued for an individual target protein and across the population of brain proteins by the phosphomimetic, whereas the dephosphomimetic phenocopies the null condition. At the cellular level, dfmr1 null synapse architecture exhibits increased area, branching and bouton number. The phosphomimetic fully rescues these synaptogenesis defects, whereas the dephosphomimetic provides no rescue. The presence of Futsch-positive (microtubule-associated protein 1B) supernumerary microtubule loops is elevated in dfmr1 null synapses. The human phosphomimetic restores normal Futsch loops, whereas the dephosphomimetic provides no activity. At the behavioral level, dfmr1 null mutants exhibit strongly impaired olfactory associative learning. The human phosphomimetic targeted only to the brain-learning center restores normal learning ability, whereas the dephosphomimetic provides absolutely no rescue. We conclude that human FMRP S500 phosphorylation is necessary for its in vivo function as a neuronal translational repressor and regulator of synaptic architecture, and for the manifestation of FMRP-dependent learning behavior. PMID:22080836

Coffee, R Lane; Williamson, Ashley J; Adkins, Christopher M; Gray, Marisa C; Page, Terry L; Broadie, Kendal

2011-11-11

204

In vivo neuronal function of the fragile X mental retardation protein is regulated by phosphorylation  

PubMed Central

Fragile X syndrome (FXS), caused by loss of the Fragile X Mental Retardation 1 (FMR1) gene product (FMRP), is the most common heritable cause of intellectual disability and autism spectrum disorders. It has been long hypothesized that the phosphorylation of serine 500 (S500) in human FMRP controls its function as an RNA-binding translational repressor. To test this hypothesis in vivo, we employed neuronally targeted expression of three human FMR1 transgenes, including wild-type (hFMR1), dephosphomimetic (S500A-hFMR1) and phosphomimetic (S500D-hFMR1), in the Drosophila FXS disease model to investigate phosphorylation requirements. At the molecular level, dfmr1 null mutants exhibit elevated brain protein levels due to loss of translational repressor activity. This defect is rescued for an individual target protein and across the population of brain proteins by the phosphomimetic, whereas the dephosphomimetic phenocopies the null condition. At the cellular level, dfmr1 null synapse architecture exhibits increased area, branching and bouton number. The phosphomimetic fully rescues these synaptogenesis defects, whereas the dephosphomimetic provides no rescue. The presence of Futsch-positive (microtubule-associated protein 1B) supernumerary microtubule loops is elevated in dfmr1 null synapses. The human phosphomimetic restores normal Futsch loops, whereas the dephosphomimetic provides no activity. At the behavioral level, dfmr1 null mutants exhibit strongly impaired olfactory associative learning. The human phosphomimetic targeted only to the brain-learning center restores normal learning ability, whereas the dephosphomimetic provides absolutely no rescue. We conclude that human FMRP S500 phosphorylation is necessary for its in vivo function as a neuronal translational repressor and regulator of synaptic architecture, and for the manifestation of FMRP-dependent learning behavior.

Coffee, R. Lane; Williamson, Ashley J.; Adkins, Christopher M.; Gray, Marisa C.; Page, Terry L.; Broadie, Kendal

2012-01-01

205

Atypical Membrane Topology and Heteromeric Function of Drosophila Odorant Receptors In Vivo  

PubMed Central

Drosophila olfactory sensory neurons (OSNs) each express two odorant receptors (ORs): a divergent member of the OR family and the highly conserved, broadly expressed receptor OR83b. OR83b is essential for olfaction in vivo and enhances OR function in vitro, but the molecular mechanism by which it acts is unknown. Here we demonstrate that OR83b heterodimerizes with conventional ORs early in the endomembrane system in OSNs, couples these complexes to the conserved ciliary trafficking pathway, and is essential to maintain the OR/OR83b complex within the sensory cilia, where odor signal transduction occurs. The OR/OR83b complex is necessary and sufficient to promote functional reconstitution of odor-evoked signaling in sensory neurons that normally respond only to carbon dioxide. Unexpectedly, unlike all known vertebrate and nematode chemosensory receptors, we find that Drosophila ORs and OR83b adopt a novel membrane topology with their N-termini and the most conserved loops in the cytoplasm. These loops mediate direct association of ORs with OR83b. Our results reveal that OR83b is a universal and integral part of the functional OR in Drosophila. This atypical heteromeric and topological design appears to be an insect-specific solution for odor recognition, making the OR/OR83b complex an attractive target for the development of highly selective insect repellents to disrupt olfactory-mediated host-seeking behaviors of insect disease vectors.

Benton, Richard; Sachse, Silke; Michnick, Stephen W

2006-01-01

206

In vivo optogenetic tracing of functional corticocortical connections between motor forelimb areas  

PubMed Central

Interactions between distinct motor cortical areas are essential for coordinated motor behaviors. In rodents, the motor cortical forelimb areas are divided into at least two distinct areas: the rostral forelimb area (RFA) and the caudal forelimb area (CFA). The RFA is thought to be an equivalent of the premotor cortex (PM) in primates, whereas the CFA is believed to be an equivalent of the primary motor cortex. Although reciprocal connections between the RFA and the CFA have been anatomically identified in rats, it is unknown whether there are functional connections between these areas that can induce postsynaptic spikes. In this study, we used an in vivo Channelrhodopsin-2 (ChR2) photostimulation method to trace the functional connections between the mouse RFA and CFA. Simultaneous electrical recordings were utilized to detect spiking activities induced by synaptic inputs originating from photostimulated areas. This method, in combination with anatomical tracing, demonstrated that the RFA receives strong functional projections from layer 2/3 and/or layer 5a, but not from layer 5b (L5b), of the CFA. Further, the CFA receives strong projections from L5b neurons of the RFA. The onset latency of electrical responses evoked in remote areas upon photostimulation of the other areas was approximately 10 ms, which is consistent with the synaptic connectivity between these areas. Our results suggest that neuronal activities in the RFA and the CFA during movements are formed through asymmetric reciprocal connections.

Hira, Riichiro; Ohkubo, Fuki; Tanaka, Yasuhiro R.; Masamizu, Yoshito; Augustine, George J.; Kasai, Haruo; Matsuzaki, Masanori

2013-01-01

207

In vivo mapping of functional connectivity in neurotransmitter systems using pharmacological MRI.  

PubMed

Pharmacological MRI (phMRI) methods map the hemodynamic response to drug challenge as a surrogate for changes in neuronal activity. However, the central effects of drugs can be complex and include activity at the primary site of action, downstream effects in other brain regions and direct effects on vasculature and neurovascular coupling. Univariate analysis, normally applied to phMRI data, does not discriminate between these effects, and can result in anatomically non-specific activation patterns. We analysed inter-subject correlations in the amplitude of the slow phMRI response to map functionally connected brain regions recruited in response to pharmacological challenge. Application of D-amphetamine and fluoxetine revealed well-defined functional structure underlying the widespread signal changes detected via standard methods. Correlated responses were found to delineate key neurotransmitter pathways selectively targeted by these drugs, corroborating a tight correspondence between the phMRI response and changes in neurotransmitter systems specific to the pharmacological action. In vivo mapping of correlated responses in this way greatly extends the range of information available from phMRI studies and provides a new window into the function of neurotransmitter systems in the active state. This approach may provide new important insights regarding the central systems underlying pharmacological action. PMID:17188903

Schwarz, Adam J; Gozzi, Alessandro; Reese, Torsten; Bifone, Angelo

2006-12-26

208

In Vivo Analysis of Lrig Genes Reveals Redundant and Independent Functions in the Inner Ear  

PubMed Central

Lrig proteins are conserved transmembrane proteins that modulate a variety of signaling pathways from worm to humans. In mammals, there are three family members – Lrig1, Lrig2, and Lrig3 – that are defined by closely related extracellular domains with a similar arrangement of leucine rich repeats and immunoglobulin domains. However, the intracellular domains show little homology. Lrig1 inhibits EGF signaling through internalization and degradation of ErbB receptors. Although Lrig3 can also bind ErbB receptors in vitro, it is unclear whether Lrig2 and Lrig3 exhibit similar functions to Lrig1. To gain insights into Lrig gene functions in vivo, we compared the expression and function of the Lrigs in the inner ear, which offers a sensitive system for detecting effects on morphogenesis and function. We find that all three family members are expressed in the inner ear throughout development, with Lrig1 and Lrig3 restricted to subsets of cells and Lrig2 expressed more broadly. Lrig1 and Lrig3 overlap prominently in the developing vestibular apparatus and simultaneous removal of both genes disrupts inner ear morphogenesis. This suggests that these two family members act redundantly in the otic epithelium. In contrast, although Lrig1 and Lrig2 are frequently co-expressed, Lrig1?/?;Lrig2?/? double mutant ears show no enhanced structural abnormalities. At later stages, Lrig1 expression is sustained in non-sensory tissues, whereas Lrig2 levels are enhanced in neurons and sensory epithelia. Consistent with these distinct expression patterns, Lrig1 and Lrig2 mutant mice exhibit different forms of impaired auditory responsiveness. Notably, Lrig1?/?;Lrig2?/? double mutant mice display vestibular deficits and suffer from a more severe auditory defect that is accompanied by a cochlear innervation phenotype not present in single mutants. Thus, Lrig genes appear to act both redundantly and independently, with Lrig2 emerging as the most functionally distinct family member.

del Rio, Tony; Nishitani, Allison M.; Yu, Wei-Ming; Goodrich, Lisa V.

2013-01-01

209

A preliminary study on the induction of dioestrous ovulation in the mare - a possible method for inducing prolonged luteal phase  

PubMed Central

Background Strong oestrous symptoms in the mare can cause problems with racing, training and handling. Since long-acting progesterone treatment is not permitted in mares at competition (e.g. according to FEI rules), there is a need for methods to suppress unwanted cyclicity. Spontaneous dioestrous ovulations in the late luteal phase may cause a prolongation of the luteal phase in mares. Methods In this preliminary study, in an attempt to induce ovulation during the luteal phase, human chorionic gonadotropin (hCG) (3000 IU) was injected intramuscularly in four mares (experimental group) in the luteal phase when a dioestrous follicle ? 30 mm was detected. A fifth mare included in this group was not treated due to no detectable dioestrous follicles ? 30 mm. Four control mares were similarly injected with saline. The mares were followed with ultrasound for 72 hours post injection or until ovulation. Blood samples for progesterone analysis were obtained twice weekly for one month and thereafter once weekly for another two to four months. Results Three of the hCG-treated mares ovulated within 72 hours after treatment and developed prolonged luteal phases of 58, 68 and 82 days respectively. One treated mare never ovulated after the hCG injection and progesterone levels fell below 3 nmol/l nine days post treatment. Progesterone levels in the control mares were below 3 nmol/l within nine days after saline injection, except for one mare, which developed a spontaneously prolonged luteal phase of 72 days. Conclusion HCG treatment may be a method to induce prolonged luteal phases in the mare provided there is a dioestrous follicle ? 30 mm that ovulates post-treatment. However, the method needs to be tested on a larger number of mares to be able to draw conclusions regarding its effectiveness.

Hedberg, Ylva; Dalin, Anne-Marie; Santesson, Malin; Kindahl, Hans

2006-01-01

210

Us3, a multifunctional protein kinase encoded by herpes simplex virus 1: how does it function in vivo?  

PubMed

: Phosphorylation is a common protein modification by which a cell or virus regulates protein activity, and subsequently cellular and viral functions. Herpesviruses commonly encode protein kinases that regulate their own replicative processes and modify host cellular machinery, by phosphorylating target proteins. Although numerous studies have revealed the multiple downstream effects of viral protein kinases and their potential molecular mechanisms, it remains unknown whether herpes viral protein kinases are involved in viral replication and pathogenicity in vivo. This review focuses on Us3 protein kinase encoded by herpes simplex virus 1 and provides a current overview of its functions in infected cells, with a special focus on their relevancy in vivo. PMID:24104928

Kawaguchi, Yasushi

2013-11-01

211

Cell-specific localization of nitric oxide synthases (NOS) in the rat ovary during follicular development, ovulation and luteal formation.  

PubMed

Nitric oxide (NO) has emerged as one of several important intraovarian regulatory factors. In particular, NO has been implicated in the processes of ovulation and atresia-related apoptosis. The aim of the present study was to investigate the presence and distribution of the NO-generating nitric oxide synthase (NOS) enzymes in the ovary during follicular development, ovulation and luteal formation of the equine chorionic gonadotrophin (ECG)/human chorionic gonadotrophin (HCG)-primed rat. NADPH diaphorase activity was used as a histochemical marker for NOS within the ovary. Diaphorase reactivity was most abundant in the stroma (S) of the ovary and in the theca (T) layer of the follicle. In luteinized ovaries, weaker diaphorase reactivity was present within the corpora lutea (CL). Two different isoforms of NOS, the constitutively expressed endothelial NOS (eNOS) and the inducible isoform of NOS (iNOS), were immunolocalized in ovaries of immature rats and in ECG/HCG-primed rats during the periovulatory period from HCG injection until 2 days after ovulation. In addition, ovarian concentrations of eNOS and iNOS were quantified by immunoblotting. Immunoblotting with a monoclonal anti-eNOS antibody demonstrated the presence of eNOS mainly in the residual ovary (ROV) during the periovulatory period. In luteinized ovaries, higher concentrations of eNOS were seen in CL, while those in the ROV at this stage were lower than in the periovulatory ovary. Immature ovaries contained diminutive amounts of eNOS, detectable mostly in the ROV compartment. In contrast, iNOS was barely detectable during follicular development to the preovulatory stage. A slight elevation of iNOS was observed in the granulosa cells at 6 h after the HCG injection. The levels of iNOS during the luteal phase were also low. Immunohistochemical analysis using polyclonal eNOS and iNOS antibodies revealed the localization of these two isoforms primarily in the S and the T of the periovulatory ovary. In luteinized ovaries, positive immunoreactivity was also seen within the CL. With a monoclonal antibody against eNOS, intense immunoreactivity was observed in the S, T and within CL. There was a particularly strong staining in blood vessels. These data demonstrate the presence of an intraovarian NO-generating system. The localization of this system to the S, T and CL suggests a role for NO in the ovulatory process and in the regulation of CL function. PMID:9021370

Zackrisson, U; Mikuni, M; Wallin, A; Delbro, D; Hedin, L; Brännström, M

1996-12-01

212

Human Retinal Pigment Epithelium Cells as Functional Models for the RPE In Vivo  

PubMed Central

Purpose. The two most commonly used in vitro models of the retinal pigment epithelium (RPE) are fetal human RPE (fhRPE) and ARPE-19 cells; however, studies of their barrier properties have produced contradictory results. To compare their utility as RPE models, their morphologic and functional characteristics were analyzed. Methods. Monolayers of both cell types were grown on permeable membrane filters. Barrier function and cellular morphology were assessed by transepithelial resistance (TER) measurements and immunohistochemistry. Protein expression was evaluated by immunoblotting and ELISA assays, and retinoid metabolism characterized by HPLC. Results. Both cultures developed tight junctions. However, only the fhRPE cells were pigmented, uniform in size and shape, expressed high levels of RPE markers, metabolized all-trans retinal, and developed high TER (>400 ?cm2). The net secretion of pigment-epithelium-derived factor (PEDF) was directed apically in both cultures, but fhRPE cells exhibited secretion rates a thousand-fold greater than in ARPE-19 cells. The net secretion of vascular endothelial growth factor (VEGF) was significantly higher in fhRPE cultures and the direction of this secretion was basolateral; while net secretion was apical in ARPE-19 cells. In fresh media, VEGF-E reduced TER in both cultures; however, in conditioned media fhRPE cells did not respond to VEGF-E administration, but retreatment of the conditioned media with anti-PEDF antibodies allowed fhRPE cells to fully respond to VEGF-E. Conclusions. Properties of fhRPE cells align with a functionally normal RPE in vivo, while ARPE-19 cells resemble a pathologic or aged RPE. These results suggest a utility for both cell types in understanding distinct, particular aspects of RPE function.

Dahrouj, Mohammad; Tang, Peter H.; Liu, Yueying; Sambamurti, Kumar; Marmorstein, Alan D.; Crosson, Craig E.

2011-01-01

213

Conditional gene deletion reveals functional redundancy of GABAB receptors in peripheral nociceptors in vivo  

PubMed Central

Background ?-aminobutyric acid (GABA) is an important inhibitory neurotransmitter which mainly mediates its effects on neurons via ionotropic (GABAA) and metabotropic (GABAB) receptors. GABAB receptors are widely expressed in the central and the peripheral nervous system. Although there is evidence for a key function of GABAB receptors in the modulation of pain, the relative contribution of peripherally- versus centrally-expressed GABAB receptors is unclear. Results In order to elucidate the functional relevance of GABAB receptors expressed in peripheral nociceptive neurons in pain modulation we generated and analyzed conditional mouse mutants lacking functional GABAB(1) subunit specifically in nociceptors, preserving expression in the spinal cord and brain (SNS-GABAB(1)-/- mice). Lack of the GABAB(1) subunit precludes the assembly of functional GABAB receptor. We analyzed SNS-GABAB(1)-/- mice and their control littermates in several models of acute and neuropathic pain. Electrophysiological studies on peripheral afferents revealed higher firing frequencies in SNS-GABAB(1)-/- mice compared to corresponding control littermates. However no differences were seen in basal nociceptive sensitivity between these groups. The development of neuropathic and chronic inflammatory pain was similar across the two genotypes. The duration of nocifensive responses evoked by intraplantar formalin injection was prolonged in the SNS-GABAB(1)-/- animals as compared to their control littermates. Pharmacological experiments revealed that systemic baclofen-induced inhibition of formalin-induced nociceptive behaviors was not dependent upon GABAB(1) expression in nociceptors. Conclusion This study addressed contribution of GABAB receptors expressed on primary afferent nociceptive fibers to the modulation of pain. We observed that neither the development of acute and chronic pain nor the analgesic effects of a systematically-delivered GABAB agonist was significantly changed upon a specific deletion of GABAB receptors from peripheral nociceptive neurons in vivo. This lets us conclude that GABAB receptors in the peripheral nervous system play a less important role than those in the central nervous system in the regulation of pain.

2009-01-01

214

In vivo circulation, clearance, and biodistribution of polyglycerol grafted functional red blood cells.  

PubMed

The in vivo circulation of hyperbranched polyglycerol (HPG) grafted red blood cells (RBCs) was investigated in mice. The number of HPG molecules grafted per RBC was measured using tritium labeled HPGs ((3)H-HPG) of different molecular weights; the values ranged from 1 × 10(5) to 2 × 10(6) molecules per RBC. HPG-grafted RBCs were characterized in vitro by measuring the electrophoretic mobility, complement mediated lysis, and osmotic fragility. Our results show that RBCs grafted with 1.5 × 10(5) HPG molecules per RBC having molecular weights 20 and 60 kDa have similar characteristics as that of control RBCs. The in vivo circulation of HPG-grafted RBCs was measured by a tail vain injection of (3)H-HPG60K-RBC in mice. The radioactivity of isolated RBCs, whole blood, plasma, different organs, urine and feces was evaluated at different time intervals. The portion of (3)H-HPG60K-RBC that survived the first day in mice (52%) remained in circulation for 50 days. Minimal accumulation radioactivity in organs other than liver and spleen was observed suggesting the normal clearance mechanism of modified RBCs. Animals gained normal weights and no abnormalities observed in necropsy analysis. The stability of the ester-amide linker between the RBC and HPG was evaluated by comparing the clearance rate of (3)H-HPG60K-RBC and PKH-26 lipid fluorescent membrane marker labeled HPG60K-RBCs. HPG modified RBCs combine the many advantages of a dendritic polymer and RBCs, and hold great promise in systemic drug delivery and other applications of functional RBC. PMID:22261097

Chapanian, Rafi; Constantinescu, Iren; Brooks, Donald E; Scott, Mark D; Kizhakkedathu, Jayachandran N

2012-01-18

215

Functional significance of glutamate-cysteine ligase modifier for erythrocyte survival in vitro and in vivo.  

PubMed

Erythrocytes endure constant exposure to oxidative stress. The major oxidative stress scavenger in erythrocytes is glutathione. The rate-limiting enzyme for glutathione synthesis is glutamate-cysteine ligase, which consists of a catalytic subunit (GCLC) and a modifier subunit (GCLM). Here, we examined erythrocyte survival in GCLM-deficient (gclm(-/-)) mice. Erythrocytes from gclm(-/-) mice showed greatly reduced intracellular glutathione. Prolonged incubation resulted in complete lysis of gclm(-/-) erythrocytes, which could be reversed by exogenous delivery of the antioxidant Trolox. To test the importance of GCLM in vivo, mice were treated with phenylhydrazine (PHZ; 0.07?mg/g b.w.) to induce oxidative stress. Gclm(-/-) mice showed dramatically increased hemolysis compared with gclm(+/+) controls. In addition, PHZ-treated gclm(-/-) mice displayed markedly larger accumulations of injured erythrocytes in the spleen than gclm(+/+) mice within 24?h of treatment. Iron staining indicated precipitations of the erythrocyte-derived pigment hemosiderin in kidney tubules of gclm(-/-) mice and none in gclm(+/+) controls. In fact, 24?h after treatment, kidney function began to diminish in gclm(-/-) mice as evident from increased serum creatinine and urea. Consequently, while all PHZ-treated gclm(+/+) mice survived, 90% of PHZ-treated gclm(-/-) mice died within 5 days of treatment. In vitro, upon incubation in the absence or presence of additional oxidative stress, gclm(-/-) erythrocytes exposed significantly more phosphatidylserine, a cell death marker, than gclm(+/+) erythrocytes, an effect at least partially due to increased cytosolic Ca(2+) concentration. Under resting conditions, gclm(-/-) mice exhibited reticulocytosis, indicating that the enhanced erythrocyte death was offset by accelerated erythrocyte generation. GCLM is thus indispensable for erythrocyte survival, in vitro and in vivo, during oxidative stress. PMID:23787995

Föller, M; Harris, I S; Elia, A; John, R; Lang, F; Kavanagh, T J; Mak, T W

2013-06-21

216

Characterization of in vivo functions of Nicotiana benthamiana RabE1.  

PubMed

We characterized the gene expression, subcellular localization, and in vivo functions of a Nicotiana benthamiana small GTPase belonging to the RabE family, designated NbRabE1. The NbRabE1 promoter drove strong ?-glucuronidase reporter expression in young tissues containing actively dividing cells and in stomata guard cells. GFP fusion proteins of NbRabE1 and its dominant-negative and constitutively active mutants were all localized to the Golgi apparatus and the plasma membrane but showed different affinities for membrane attachment. Virus-induced gene silencing of NbRabE1 resulted in pleiotropic phenotypes, including growth arrest, premature senescence, and abnormal leaf development. At the cellular level, the leaves in which NbRabE1 was silenced contained abnormal stomata that lacked pores or contained incomplete ventral walls, suggesting that NbRabE1 deficiency leads to defective guard cell cytokinesis. Ectopic expression of the dominant-negative mutant of NbRabE1 in Arabidopsis thaliana resulted in retardation of shoot and root growth accompanied by defective root hair formation. These developmental defects are discussed in conjunction with proposed functions of RabE GTPases in polarized secretory vesicle trafficking. PMID:23001196

Ahn, Chang Sook; Han, Jeong-A; Pai, Hyun-Sook

2012-09-22

217

Humanized large-scale expanded endothelial colony-forming cells function in vitro and in vivo  

PubMed Central

Endothelial progenitor cells are critically involved in essential biologic processes, such as vascular homeostasis, regeneration, and tumor angiogenesis. Endothelial colony–forming cells (ECFCs) are endothelial progenitor cells with robust proliferative potential. Their profound vessel-forming capacity makes them a promising tool for innovative experimental, diagnostic, and therapeutic strategies. Efficient and safe methods for their isolation and expansion are presently lacking. Based on the previously established efficacy of animal serum–free large-scale clinical-grade propagation of mesenchymal stromal cells, we hypothesized that endothelial lineage cells may also be propagated efficiently following a comparable strategy. Here we demonstrate that human ECFCs can be recovered directly from unmanipulated whole blood. A novel large-scale animal protein-free humanized expansion strategy preserves the progenitor hierarchy with sustained proliferation potential of more than 30 population doublings. By applying large-scale propagated ECFCs in various test systems, we observed vascular networks in vitro and perfused vessels in vivo. After large-scale expansion and cryopreservation phenotype, function, proliferation, and genomic stability were maintained. For the first time, proliferative, functional, and storable ECFCs propagated under humanized conditions can be explored in terms of their therapeutic applicability and risk profile.

Reinisch, Andreas; Hofmann, Nicole A.; Obenauf, Anna C.; Kashofer, Karl; Rohde, Eva; Schallmoser, Katharina; Flicker, Karin; Lanzer, Gerhard; Linkesch, Werner; Speicher, Michael R.

2009-01-01

218

In vivo effects of eltrombopag on platelet function in immune thrombocytopenia: no evidence of platelet activation  

PubMed Central

The effects of eltrombopag, a thrombopoietin-receptor agonist, on platelet function in immune thrombocytopenia (ITP) are not fully characterized. This study used whole blood flow cytometry to examine platelet function in 20 patients receiving eltrombopag treatment at days 0, 7, and 28. Platelet surface expression of activated GPIIb/IIIa, P-selectin, and GPIb was measured with and without low and high adenosine diphosphate (ADP) and thrombin receptor activating peptide (TRAP) concentrations. Before eltrombopag treatment with no ex vivo agonist, platelet activation was higher in ITP patients than controls. Platelet GPIb and activated GPIIb/IIIa expression without added agonist was unchanged following eltrombopag treatment, whereas a slight increase in P-selectin was observed. Expression of P-selectin and activated GPIIb/IIIa in response to high-dose ADP was lower during eltrombopag treatment than at baseline. Eltrombopag led to a slight increase in platelet reactivity to TRAP only in responders to eltrombopag but not to levels above those in controls; whole blood experiments demonstrated that this increase was probably because of higher platelet counts rather than higher platelet reactivity. In conclusion, although thrombocytopenic ITP patients have higher baseline platelet activation than controls, eltrombopag did not cause platelet activation or hyper-reactivity, irrespective of whether the platelet count increased.

Psaila, Bethan; Bussel, James B.; Linden, Matthew D.; Babula, Bracken; Li, Youfu; Barnard, Marc R.; Tate, Chinara; Mathur, Kanika; Frelinger, Andrew L.

2012-01-01

219

In vivo effects of eltrombopag on platelet function in immune thrombocytopenia: no evidence of platelet activation.  

PubMed

The effects of eltrombopag, a thrombopoietin-receptor agonist, on platelet function in immune thrombocytopenia (ITP) are not fully characterized. This study used whole blood flow cytometry to examine platelet function in 20 patients receiving eltrombopag treatment at days 0, 7, and 28. Platelet surface expression of activated GPIIb/IIIa, P-selectin, and GPIb was measured with and without low and high adenosine diphosphate (ADP) and thrombin receptor activating peptide (TRAP) concentrations. Before eltrombopag treatment with no ex vivo agonist, platelet activation was higher in ITP patients than controls. Platelet GPIb and activated GPIIb/IIIa expression without added agonist was unchanged following eltrombopag treatment, whereas a slight increase in P-selectin was observed. Expression of P-selectin and activated GPIIb/IIIa in response to high-dose ADP was lower during eltrombopag treatment than at baseline. Eltrombopag led to a slight increase in platelet reactivity to TRAP only in responders to eltrombopag but not to levels above those in controls; whole blood experiments demonstrated that this increase was probably because of higher platelet counts rather than higher platelet reactivity. In conclusion, although thrombocytopenic ITP patients have higher baseline platelet activation than controls, eltrombopag did not cause platelet activation or hyper-reactivity, irrespective of whether the platelet count increased. PMID:22294727

Psaila, Bethan; Bussel, James B; Linden, Matthew D; Babula, Bracken; Li, Youfu; Barnard, Marc R; Tate, Chinara; Mathur, Kanika; Frelinger, Andrew L; Michelson, Alan D

2012-01-31

220

Effects of altered ventilatory patterns of rabbit pulmonary endothelial angiotensin converting enzyme function, in vivo  

SciTech Connect

Because alveolar pressure can influence pulmonary blood flow, volume and surface area, the authors have studied the effects of airway pressure on endothelial angiotensin converting enzyme (ACE) function in rabbit lungs in vivo, utilizing indicator dilution techniques with /sup 3/H-Benzoyl-Phe-Ala-Pro (BPAP) as substate. Static inclation of the lungs to a pressure of 0 or 5 mmHg did not change percent transpulmonary metabolism and Amax/Km ratio in comparison to control measurements during conventional mechanical ventilation. When the inflation pressure was increased to 10 mmHg, percent metabolism of /sup 3/H-BPAP remained unaltered but Amax/Km decreased over 40% from control. This decrease was in close relation to the reduction in pulmonary blood flow. Addition of 5 cm H/sub 2/O positive end-expiratory pressure (PEEP) to the mechanical ventilation also decreased Amax/Km values and pulmonary blood flow but did not influence percent metabolism of /sup 3/H-BPAP. These results suggest that the detected alterations in ACE kinetics were more likely due to hemodynamic changes than enzyme dysfunction. The authors propose that high static alveolar pressures as well as PEEP did not affect angiotensin converting enzyme function, but reduced the fraction of perfused microvessels reflected in changes in Amax/Km ratios.

Toivonen, H.J.; Catravas, J.D.

1986-03-01

221

Twins, quadruplexes, and more: functional aspects of native and engineered RNA self-assembly in vivo  

PubMed Central

The primacy and power of RNA in governing many processes of life has begun to be more fully appreciated in both the discovery and inventive sciences. A variety of RNA interactions regulate gene expression, and structural self-assembly underlies many of these processes. The understanding sparked by these discoveries has inspired and informed the engineering of novel RNA structures, control elements, and genetic circuits in cells. Many of these engineered systems are built up fundamentally from RNA–RNA interactions, often combining modular, rational design with functional selection and screening. It is therefore useful to review the particular class of RNA-based regulatory mechanisms that rely on RNA self-assembly either through homomeric (self–self) or heteromeric (self–nonself) RNA–RNA interactions. Structures and sequence elements within individual RNAs create a basis for the pairing interactions, and in some instances can even lead to the formation of RNA polymers. Example systems of dimers, multimers, and polymers are reviewed in this article in the context of natural systems, wherein the function and impact of self-assemblies are understood. Following this, a brief overview is presented of specific engineered RNA self-assembly systems implemented in vivo, with lessons learned from both discovery and engineering approaches to RNA–RNA self-assembly.

Lease, Richard A.; Arluison, Veronique; Lavelle, Christophe

2013-01-01

222

Monitoring of In Vivo Function of Superparamagnetic Iron Oxide Labelled Murine Dendritic Cells during Anti-Tumour Vaccination  

PubMed Central

Dendritic cells (DCs) generated in vitro to present tumour antigens have been injected in cancer patients to boost in vivo anti-tumour immune responses. This approach to cancer immunotherapy has had limited success. For anti-tumour therapy, delivery and subsequent migration of DCs to lymph nodes leading to effective stimulation of effector T cells is thought to be essential. The ability to non-invasively monitor the fate of adoptively transferred DCs in vivo using magnetic resonance imaging (MRI) is an important clinical tool to correlate their in vivo behavior with response to treatment. Previous reports of superparamagnetic iron oxides (SPIOs) labelling of different cell types, including DCs, have indicated varying detrimental effects on cell viability, migration, differentiation and immune function. Here we describe an optimised labelling procedure using a short incubation time and low concentration of clinically used SPIO Endorem to successfully track murine DC migration in vivo using MRI in a mouse tumour model. First, intracellular labelling of bone marrow derived DCs was monitored in vitro using electron microscopy and MRI relaxometry. Second, the in vitro characterisation of SPIO labelled DCs demonstrated that viability, phenotype and functions were comparable to unlabelled DCs. Third, ex vivo SPIO labelled DCs, when injected subcutaneously, allowed for the longitudinal monitoring by MR imaging of their migration in vivo. Fourth, the SPIO DCs induced the proliferation of adoptively transferred CD4+ T cells but, most importantly, they primed cytotoxic CD8+ T cell responses to protect against a B16-Ova tumour challenge. Finally, using anatomical information from the MR images, the immigration of DCs was confirmed by the increase in lymph node size post-DC injection. These results demonstrate that the SPIO labelling protocol developed in this study is not detrimental for DC function in vitro and in vivo has potential clinical application in monitoring therapeutic DCs in patients with cancer.

Tavare, Richard; Sagoo, Pervinder; Varama, Gopal; Tanriver, Yakup; Warely, Alice; Diebold, Sandra S.; Southworth, Richard; Schaeffter, Tobias; Lechler, Robert I.; Razavi, Reza; Lombardi, Giovanna; Mullen, Gregory E. D.

2011-01-01

223

In VivoFunctional Imaging of Intrinsic Scattering Changes in the Human Retina with High-speed Ultrahigh Resolution OCT  

PubMed Central

Non-invasive methods of probing retinal function are of interest for the early detection of retinal disease. While retinal function is traditionally directly measured with the electroretinogram (ERG), recently functional optical imaging of the retina has been demonstrated. In this manuscript, stimulus-induced, intrinsic optical scattering changes in the human retina are measured in vivo with high-speed, ultrahigh resolution optical coherence tomography (OCT) operating at 50,000 axial scans per second and ?3.3 micron axial resolution. A stimulus and measurement protocol that enables measurement of functional OCT retinal signals is described. OCT signal changes in the photoreceptors are demonstrated. Two distinct responses having different temporal and spatial properties are reported. These results are discussed in the context of optical intrinsic signals measured previously in the retina by fundus imaging and scanning laser ophthalmoscopy. Finally, challenges associated with in vivo functional retinal imaging in human subjects are discussed.

Srinivasan, V. J.; Chen, Y.; Duker, J. S.; Fujimoto, J. G.

2009-01-01

224

An in vivo analysis of the vestigial gene in Drosophila melanogaster defines the domains required for Vg function.  

PubMed Central

Considerable evidence indicates an obligate partnership of the Drosophila melanogaster Vestigial (VG) and Scalloped (SD) proteins within the context of wing development. These two proteins interact physically and a 56-amino-acid motif within VG is necessary and sufficient for this binding. While the importance of this SD-binding domain has been clearly demonstrated both in vitro and in vivo, the remaining portions of VG have not been examined for in vivo function. Herein, additional regions within VG were tested for possible in vivo functions. The results identify two additional domains that must be present for optimal VG function as measured by the loss of ability to rescue vg mutants, to induce ectopic sd expression, and to perform other normal VG functions when they are deleted. An in vivo study such as this one is fundamentally important because it identifies domains of VG that are necessary in the cellular context in which wing development actually occurs. The results also indicate that an additional large portion of VG, outside of these two domains and the SD-binding domain, is dispensable in the execution of these normal VG functions.

MacKay, Julie O; Soanes, Kelly H; Srivastava, Ajay; Simmonds, Andrew; Brook, William J; Bell, John B

2003-01-01

225

The past, present, and future of x-ray technology for in vivo imaging of function and form  

SciTech Connect

Scientists and clinicians have a keen interest in studying not just the structure of physiological systems, but their motion also, or more generally their form and function. This paper focuses on the technologies that underpin in vivo measurements of form and function of the human body for both research and medical treatment. A concise literature review of x-ray imaging, ultrasonography, magnetic resonance imaging, radionuclide imaging, laser Doppler velocimetry, and particle image velocimetry is presented. Additionally, a more detailed review of in vivo x-ray imaging is presented. Finally, two techniques, which the authors believe are representative of the present and future of in vivo x-ray imaging techniques, are presented.

Fouras, A.; Dubsky, S.; Hourigan, K. [Division of Biological Engineering, Monash University, Clayton, Victoria 3800 (Australia) and Fluids Laboratory for Aeronautical and Industrial Research, Monash University, Clayton, Victoria 3800 (Australia); Kitchen, M. J. [School of Physics, Monash University, Clayton, Victoria 3800 (Australia); Lewis, R. A. [Monash Center for Synchrotron Science, Monash University, Clayton, Victoria 3800 (Australia); Hooper, S. B. [Department of Physiology, Monash University, Clayton, Victoria 3800 (Australia)

2009-05-15

226

Reproductive biology and IVF: ovarian stimulation and luteal phase consequences  

Microsoft Academic Search

Most clinicians working in in vitro fertilization (IVF) centers worldwide have taken for granted for more than a decade the paradigm of so-called ‘controlled’ ovarian hyperstimulation, using maximum stimulation by exogenous gonadotropins, together with the gonadotropin-releasing hormone (GnRH) agonist long-protocol. Potential detrimental effects of this approach with regard to oocyte quality, corpus luteum function and endometrial receptivity have been largely

Bart C. J. M. Fauser; Paul Devroey

2003-01-01

227

Soil engineering in vivo: harnessing natural biogeochemical systems for sustainable, multi-functional engineering solutions  

PubMed Central

Carbon sequestration, infrastructure rehabilitation, brownfields clean-up, hazardous waste disposal, water resources protection and global warming—these twenty-first century challenges can neither be solved by the high-energy consumptive practices that hallmark industry today, nor by minor tweaking or optimization of these processes. A more radical, holistic approach is required to develop the sustainable solutions society needs. Most of the above challenges occur within, are supported on, are enabled by or grown from soil. Soil, contrary to conventional civil engineering thought, is a living system host to multiple simultaneous processes. It is proposed herein that ‘soil engineering in vivo’, wherein the natural capacity of soil as a living ecosystem is used to provide multiple solutions simultaneously, may provide new, innovative, sustainable solutions to some of these great challenges of the twenty-first century. This requires a multi-disciplinary perspective that embraces the science of biology, chemistry and physics and applies this knowledge to provide multi-functional civil and environmental engineering designs for the soil environment. For example, can native soil bacterial species moderate the carbonate cycle in soils to simultaneously solidify liquefiable soil, immobilize reactive heavy metals and sequester carbon—effectively providing civil engineering functionality while clarifying the ground water and removing carbon from the atmosphere? Exploration of these ideas has begun in earnest in recent years. This paper explores the potential, challenges and opportunities of this new field, and highlights one biogeochemical function of soil that has shown promise and is developing rapidly as a new technology. The example is used to propose a generalized approach in which the potential of this new field can be fully realized.

DeJong, Jason T.; Soga, Kenichi; Banwart, Steven A.; Whalley, W. Richard; Ginn, Timothy R.; Nelson, Douglas C.; Mortensen, Brina M.; Martinez, Brian C.; Barkouki, Tammer

2011-01-01

228

Transdifferentiation of Fast Skeletal Muscle Into Functional Endothelium in Vivo by Transcription Factor Etv2  

PubMed Central

Etsrp/Etv2 (Etv2) is an evolutionarily conserved master regulator of vascular development in vertebrates. Etv2 deficiency prevents the proper specification of the endothelial cell lineage, while its overexpression causes expansion of the endothelial cell lineage in the early embryo or in embryonic stem cells. We hypothesized that Etv2 alone is capable of transdifferentiating later somatic cells into endothelial cells. Using heat shock inducible Etv2 transgenic zebrafish, we demonstrate that Etv2 expression alone is sufficient to transdifferentiate fast skeletal muscle cells into functional blood vessels. Following heat treatment, fast skeletal muscle cells turn on vascular genes and repress muscle genes. Time-lapse imaging clearly shows that muscle cells turn on vascular gene expression, undergo dramatic morphological changes, and integrate into the existing vascular network. Lineage tracing and immunostaining confirm that fast skeletal muscle cells are the source of these newly generated vessels. Microangiography and observed blood flow demonstrated that this new vasculature is capable of supporting circulation. Using pharmacological, transgenic, and morpholino approaches, we further establish that the canonical Wnt pathway is important for induction of the transdifferentiation process, whereas the VEGF pathway provides a maturation signal for the endothelial fate. Additionally, overexpression of Etv2 in mammalian myoblast cells, but not in other cell types examined, induced expression of vascular genes. We have demonstrated in zebrafish that expression of Etv2 alone is sufficient to transdifferentiate fast skeletal muscle into functional endothelial cells in vivo. Given the evolutionarily conserved function of this transcription factor and the responsiveness of mammalian myoblasts to Etv2, it is likely that mammalian muscle cells will respond similarly.

Gomez, Gustavo A.; Lindgren, Anne G.; Huang, Haigen; Yang, Hanshuo; Yao, Shaohua; Martin, Benjamin L.; Kimelman, David; Lin, Shuo

2013-01-01

229

Soil engineering in vivo: harnessing natural biogeochemical systems for sustainable, multi-functional engineering solutions.  

PubMed

Carbon sequestration, infrastructure rehabilitation, brownfields clean-up, hazardous waste disposal, water resources protection and global warming-these twenty-first century challenges can neither be solved by the high-energy consumptive practices that hallmark industry today, nor by minor tweaking or optimization of these processes. A more radical, holistic approach is required to develop the sustainable solutions society needs. Most of the above challenges occur within, are supported on, are enabled by or grown from soil. Soil, contrary to conventional civil engineering thought, is a living system host to multiple simultaneous processes. It is proposed herein that 'soil engineering in vivo', wherein the natural capacity of soil as a living ecosystem is used to provide multiple solutions simultaneously, may provide new, innovative, sustainable solutions to some of these great challenges of the twenty-first century. This requires a multi-disciplinary perspective that embraces the science of biology, chemistry and physics and applies this knowledge to provide multi-functional civil and environmental engineering designs for the soil environment. For example, can native soil bacterial species moderate the carbonate cycle in soils to simultaneously solidify liquefiable soil, immobilize reactive heavy metals and sequester carbon-effectively providing civil engineering functionality while clarifying the ground water and removing carbon from the atmosphere? Exploration of these ideas has begun in earnest in recent years. This paper explores the potential, challenges and opportunities of this new field, and highlights one biogeochemical function of soil that has shown promise and is developing rapidly as a new technology. The example is used to propose a generalized approach in which the potential of this new field can be fully realized. PMID:20829246

DeJong, Jason T; Soga, Kenichi; Banwart, Steven A; Whalley, W Richard; Ginn, Timothy R; Nelson, Douglas C; Mortensen, Brina M; Martinez, Brian C; Barkouki, Tammer

2010-09-09

230

Quantifying long-term microelectrode array functionality using chronic in vivo impedance testing  

NASA Astrophysics Data System (ADS)

Long-term acquisition of high-quality neural recordings is a cornerstone of neuroprosthetic system design. Mitigating the experimental variability of chronically implanted arrays has been a formidable task because the sensor recording sites can be influenced by biotic and abiotic responses. Several studies have implicated changes in electrical interface impedance as a preliminary marker to infer electrode viability. Microelectrode impedance plays an important role in the monitoring of low amplitude and high-resolution extracellular neural signals. In this work, we seek to quantify long-term microelectrode array functionality and derive an impedance-based predictor for electrode functionality that correlates the recording site electrical properties with the functional neuronal recordings in vivo. High temporal resolution metrics of this type would allow one to assess, predict, and improve electrode performance in the future. In a large cohort of animals, we performed daily impedance measurements and neural signal recordings over long periods (up to 21 weeks) of time in rats using tungsten microwire arrays implanted into the somatosensory cortex. This study revealed that there was a time-varying trend in the modulation of impedance that was related to electrode performance. Single units were best detected from electrodes at time points when the electrode entered into the 40-150 K? impedance range. This impedance trend was modeled across the full cohort of animals to predict future electrode performance. The model was tested on data from all animals and was able to provide predictions of electrode performance chronically. Insight from this study can be combined with knowledge of electrode materials and histological analysis to provide a more comprehensive predictive model of electrode failure in the future.

Prasad, Abhishek; Sanchez, Justin C.

2012-04-01

231

Quantifying long-term microelectrode array functionality using chronic in vivo impedance testing.  

PubMed

Long-term acquisition of high-quality neural recordings is a cornerstone of neuroprosthetic system design. Mitigating the experimental variability of chronically implanted arrays has been a formidable task because the sensor recording sites can be influenced by biotic and abiotic responses. Several studies have implicated changes in electrical interface impedance as a preliminary marker to infer electrode viability. Microelectrode impedance plays an important role in the monitoring of low amplitude and high-resolution extracellular neural signals. In this work, we seek to quantify long-term microelectrode array functionality and derive an impedance-based predictor for electrode functionality that correlates the recording site electrical properties with the functional neuronal recordings in vivo. High temporal resolution metrics of this type would allow one to assess, predict, and improve electrode performance in the future. In a large cohort of animals, we performed daily impedance measurements and neural signal recordings over long periods (up to 21 weeks) of time in rats using tungsten microwire arrays implanted into the somatosensory cortex. This study revealed that there was a time-varying trend in the modulation of impedance that was related to electrode performance. Single units were best detected from electrodes at time points when the electrode entered into the 40-150 K? impedance range. This impedance trend was modeled across the full cohort of animals to predict future electrode performance. The model was tested on data from all animals and was able to provide predictions of electrode performance chronically. Insight from this study can be combined with knowledge of electrode materials and histological analysis to provide a more comprehensive predictive model of electrode failure in the future. PMID:22442134

Prasad, Abhishek; Sanchez, Justin C

2012-03-23

232

An internal GAP domain negatively regulates presynaptic dynamin in vivo: a two-step model for dynamin function  

Microsoft Academic Search

correlates with a reduction in both the basal and assem- bly-stimulated GTPase activity in vitro. These findings demonstrate that GED is indeed an internal dynamin GAP and establish that, as for other GTPase superfamily members, dynamin's function in vivo is negatively regu- lated by its GAP activity. Based on these and other obser- vations, we propose a two-step model for

Radhakrishnan Narayanan; Marilyn Leonard; Byeong Doo Song; Sandra L. Schmid; Mani Ramaswami

2005-01-01

233

Structurally similar Drosophila alpha-tubulins are functionally distinct in vivo.  

PubMed Central

We used transgenic analysis in Drosophila to compare the ability of two structurally similar alpha-tubulin isoforms to support microtubule assembly in vivo. Our data revealed that even closely related alpha-tubulin isoforms have different functional capacities. Thus, in multicellular organisms, even small changes in tubulin structure may have important consequences for regulation of the microtubule cytoskeleton. In spermatogenesis, all microtubule functions in the postmitotic male germ cells are carried out by a single tubulin heterodimer composed of the major Drosophila alpha-84B tubulin isoform and the testis-specific beta 2-tubulin isoform. We tested the ability of the developmentally regulated alpha 85E-tubulin isoform to replace alpha 84B in spermatogenesis. Even though it is 98% similar in sequence, alpha 85E is not functionally equivalent to alpha 84B. alpha 85E can support some functional microtubules in the male germ cells, but alpha 85E causes dominant male sterility if it makes up more than one-half of the total alpha-tubulin pool in the spermatids. alpha 85E does not disrupt meiotic spindle or cytoplasmic microtubules but causes defects in morphogenesis of the two classes of singlet microtubules in the sperm tail axoneme, the central pair and the accessory microtubules. Axonemal defects caused by alpha 85E are precisely reciprocal to dominant defects in doublet microtubules we observed in a previous study of ectopic germ-line expression of the developmentally regulated beta 3-tubulin isoform. These data demonstrate that the doublet and singlet axoneme microtubules have different requirements for alpha- and beta-tubulin structure. In their normal sites of expression, alpha 85E and beta 3 are coexpressed during differentiation of several somatic cell types, suggesting that alpha 85E and beta 3 might form a specialized heterodimer. Our tests of different alpha-beta pairs in spermatogenesis did not support this model. We conclude that if alpha 85E and beta 3 have specialized properties required for their normal functions, they act independently to modulate the properties of microtubules into which they are incorporated. Images

Hutchens, J A; Hoyle, H D; Turner, F R; Raff, E C

1997-01-01

234

Prostacyclin, prostaglandin F2 alpha and progesterone production by bovine luteal cells during the estrous cycle.  

PubMed

Corpora lutea (CL) were collected from Holstein heifers on Days 5, 10, 15 and 18 (5/day) of the estrous cycle. Dispersed luteal cell preparations were made and 10(6) viable luteal cells were incubated with bovine luteinizing hormone (LH) and different amounts of arachidonic acid in the presence and absence of the prostaglandin (PG) synthetase inhibitor indomethacin. The concentrations of progesterone, PGF2 alpha and 6-keto-PGF1 alpha, the stable inactive metabolite of prostacyclin (PGI2), were measured. Day 5 CL had the greatest initial content of 6-keto-PGF1 alpha (1.01 +/- 0.16 ng/10(6) cells), and synthesized more 6-keto-PGF1 alpha (2.55 +/- 0.43) than CL collected on Days 10 (0.57 +/- 0.11), 15 (0.08 +/- 0.05) and 18 (0.19 +/- 0.03) during a 2-h incubation period. Arachidonic acid stimulated the production of 6-keto-PGF1 alpha by Days 10, 15 and 18 luteal tissue. PGF2 alpha was produced at a greater rate on Day 5 (0.69 +/- 0.17 ng/10(6) cells) than on Days 10 (0.06 +/- 0.01), 15 (0.04 +/- 0.02) and 18 (0.08 +/- 0.01). Arachidonic acid stimulated and indomethacin inhibited the production of PGF2 alpha, in most cases. The initial content of 6-keto-PGF1 alpha was higher than that of PGF2 alpha on all days of the cycle and more 6-keto-PGF1 alpha was synthesized in response to arachidonic acid addition. The ratio of 6-keto-PGF1 alpha content to PGF2 alpha content was 4.39, 2.30, 1.25 and 1.13 on Days 5, 10, 15 and 18, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6418223

Milvae, R A; Hansel, W

1983-12-01

235

Bleeding patterns in women using intramuscular progesterone for luteal support in in-vitro fertilisation cycles.  

PubMed

This paper aims to evaluate the effects of i.m. progesterone on bleeding patterns after in-vitro fertilisation embryo transfer (IVF-ET). It is a retrospective cohort study conducted in the reproductive endocrinology and IVF department of a teaching hospital. One hundred consecutive women were studied who had undergone IVF-ET using 'long protocol' stimulation with leuprolide acetate-recombinant follicle stimulating hormone (rFSH) and who did not become pregnant. Intramuscular (i.m.) progesterone (50mg once daily) was started the day before oocyte retrieval and continued for a minimum of 12-14 days following embryo transfer. The main outcome measures were time interval between oocyte retrieval and onset of bleeding, luteal phase serum progesterone and oestradiol (E2) levels, and midluteal endometrial thickness. Of the 100 patients whose charts were reviewed, 67 bled (group A) before progesterone treatment was discontinued (17 days after oocyte retrieval) and 33 (group B) bled after progesterone treatment was discontinued (> 17 days). Mean onset of bleeding was 16.2+/-2.6 days after oocyte retrieval. Serum progesterone concentrations were similar in the two groups on the day of hCG administration, whereas progesterone concentrations (in-group B) were higher on days 7 and 15 after oocyte retrieval. No statistically significant differences were found between two groups with respect to mean midluteal endometrial thickness and mean serum E2 concentrations on days 0, 7 and 15. The results suggest that i.m progesterone administration for luteal support in assisted reproduction cycles elongates luteal phase in some patients due to supraphysiological serum progesterone levels. However, most patients start to bleed in the absence of pregnancy despite continued progesterone treatment. PMID:12850858

Gürbüz, B; Yalti, S; Fiçicioglu, C; Delikara, N; Alpay, Z

2003-05-01

236

Luteal serum BDNF and HSP70 levels in women with premenstrual dysphoric disorder.  

PubMed

Premenstrual dysphoric disorder (PMDD) is a severe form of premenstrual syndrome characterized by psychological and somatic symptoms commencing in the luteal phase of the menstrual cycle and concludes with menstrual bleeding. PMDD affects 3-8 % of premenopausal women and represents a significant public health problem especially in young women. Decreased brain-derived neurotrophic factor (BDNF) levels are associated with several mental disorders. Heat-shock protein-70 (HSP70) is an important member of the molecular chaperone system, which provides a molecular defense against proteotoxic stress. We hypothesized that there would be changed levels of BDNF and HSP70 in women with PMDD compared with non-symptomatic women, reflecting impaired and/or activated stress-related responses involved in the underlying pathogenesis of PMDD. Female medical students were screened, and 24 women without premenstrual symptoms and 25 women with PMDD were enrolled in the study. Psychiatric evaluation and the Daily Record of Severity of Problems-Short Form were used for two consecutive menstrual cycles to diagnose PMDD. Serum BDNF and HSP70 levels were assessed in the third luteal phase. Participants with PMDD had significantly higher serum BDNF and HSP70 levels compared with controls, and there was a significant positive correlation between serum BDNF and HSP70 levels. Increased HSP70 levels may reflect cellular distress in PMDD. Increased serum BDNF levels in the luteal phase in subjects with PMDD may reflect a compensation process, which results in subsequent improvement of PMDD-associated depressive symptoms in the follicular phase. Thus, increased serum BDNF levels may be indicative of a compensating capacity in PMDD. PMID:23455589

Oral, E; Ozcan, H; Kirkan, T S; Askin, S; Gulec, M; Aydin, N

2013-03-01

237

Reproductive biology and IVF: ovarian stimulation and luteal phase consequences.  

PubMed

Most clinicians working in in vitro fertilization (IVF) centers worldwide have taken for granted for more than a decade the paradigm of so-called 'controlled' ovarian hyperstimulation, using maximum stimulation by exogenous gonadotropins, together with the gonadotropin-releasing hormone (GnRH) agonist long-protocol. Potential detrimental effects of this approach with regard to oocyte quality, corpus luteum function and endometrial receptivity have been largely ignored. These factors might by themselves have a major impact on IVF outcome and should therefore be considered seriously. The recent introduction of GnRH antagonists along with the current emphasis on the need for transfer of a reduced number of embryos enables a careful re-evaluation of current IVF strategies. We can now render stimulation protocols simpler, starting with a spontaneous menstrual cycle, allowing for more subtle interference with single dominant follicle selection. Here, we discuss recent approaches to ovarian stimulation, the induction of oocyte maturation, and effects of these altered follicular phase interventions on corpus luteum function following ovarian stimulation. PMID:12826330

Fauser, Bart C J M; Devroey, Paul

2003-07-01

238

3.5 Years of Insulin Therapy With Insulin Glargine Improves In Vivo Endothelial Function in Type 2 Diabetes  

Microsoft Academic Search

Objective—To determine long-term effects of insulin glargine on vascular function in patients with type 2 diabetes. Methods and Results—A total of 49 in vivo endothelial function tests, intrabrachial artery infusions of endothelium- dependent (acetylcholine (ACh)) and endothelium-independent (sodium nitroprusside (SNP)) vasoactive agents, were performed in 11 patients with type 2 diabetes (age: 592 years; BMI: 29.70.9 kg\\/m2; fasting plasma glucose:

Satu Vehkavaara; Hannele Yki-Jarvinen

2010-01-01

239

Effects of an antiprogesterone (RU486) on the hypothalamic-hypophyseal-ovarian-endometrial axis during the luteal phase of the menstrual cycle.  

PubMed

The impact of the antiprogesterone RU486 [17 beta-hydroxy-11 beta-(4-dimethylaminophenyl) 17 alpha-(1-propynyl)estra- 4,9-dien-3-one] on the hypothalamic-pituitary-ovarian-endometrial axis was examined in normal cycling women during the mid (MLP)- and late (LLP) luteal phases. During the MLP, 10 women received 3 mg/kg RU486 for 3 days. During the LLP, a single dose of 600 mg RU486 was administered to 4 women, and in another 4 women a single dose of 3 mg/kg was given during corpus luteum rescue by hCG. Longitudinal studies with daily and frequent blood samples (every 10 min for 10 h) were conducted during 3 consecutive cycles (control-treatment-recovery). During the MLP, RU486-induced uterine bleeding occurred in all 10 women 36-72 h after the first dose. No histological evidence of endometrial breakdown was found in endometrial biopsies taken 12-24 h before the onset of bleeding. Significant decreases in LH secretion (P less than 0.001) and LH pulse amplitude (P less than 0.006) and blunted pituitary responses to GnRH (P less than 0.01) were evident by the last treatment day, but LH pulse frequency did not change. Complete luteolysis occurred in 2 of the 10 women. Incomplete luteolysis occurred in 8 women and was associated with an initial decline of serum estradiol (P less than 0.001), but not progesterone levels, followed by rebound increases (P less than 0.001) in LH, estradiol, and progesterone levels 3 days later, which may have reversed the luteolytic processes and prolonged corpus luteum function. Spontaneous luteolysis ensued 3-5 days later with the onset of second episodes of uterine bleeding. For serum FSH, an early rise occurred during the luteal phase in advance of the onset of the second episodes of uterine bleeding. This rise may have resulted in early follicle recruitment and accounted for the shorter duration of the follicular phase during recovery cycles. During the LLP, the single RU486 dose resulted in significant decreases in LH pulse amplitude (P less than 0.03), frequency (P less than 0.05), and secretion (not significant) within 12 h. The recovery cycle was entirely normal. Corpus luteum rescue with incremental doses of hCG did not prevent uterine bleeding after RU486 treatment. These findings indicate that RU486 operates at multiple sites and implies that progesterone is important in the control of luteal function. Further, our data provide a basis for exploring the potential use of RU486 as a once a month birth control agent. PMID:2832438

Garzo, V G; Liu, J; Ulmann, A; Baulieu, E; Yen, S S

1988-03-01

240

The functional response of upstream DNA to dynamic supercoiling in vivo.  

PubMed

Because RNA polymerase is a powerful motor, transmission of transcription-generated forces might directly alter DNA structure, chromatin or gene activity in mammalian cells. Here we show that transcription-generated supercoils streaming dynamically from active promoters have considerable consequences for DNA structure and function in cells. Using a tamoxifen-activatable Cre recombinase to excise a test segment of chromatin positioned between divergently transcribed metallothionein-IIa promoters, we found the degree of dynamic supercoiling to increase as transcription intensified, and it was very sensitive to the specific arrangement of promoters and cis elements. Using psoralen as an in vivo probe confirmed that, during transcription, sufficient supercoiling is produced to enable transitions to conformations other than B-DNA in elements such as the human MYC far upstream element (FUSE), which in turn recruit structure-sensitive regulatory proteins, such as FUSE Binding Protein (FBP) and FBP-Interacting Repressor (FIR). These results indicate that mechanical stresses, constrained by architectural features of DNA and chromatin, may broadly contribute to gene regulation. PMID:18193062

Kouzine, Fedor; Sanford, Suzanne; Elisha-Feil, Zichrini; Levens, David

2008-01-13

241

In vivo functional analysis of the Dicistroviridae intergenic region internal ribosome entry sites  

PubMed Central

Some viral and cellular messages use an alternative mechanism to initiate protein synthesis that involves internal recruitment of the ribosome to an internal ribosome entry site (IRES). The Dicistroviridae intergenic regions (IGR) have been studied as model IRESs to understand the mechanism of IRES-mediated translation. In this study, the in vivo activity of IGR IRESs were compared. Our analysis demonstrates that Class I and II IGR IRESs have comparable translation efficiency in yeast and that Class II is significantly more active in mammalian cells. Furthermore, while Class II IGR IRES activity was enhanced in yeast grown at a higher temperature, temperature did not affect IGR IRES activity in mammalian cells. This suggests that Class II IRESs may not function optimally with yeast ribosomes. Examination of chimeric IGR IRESs, established that the IRES strength and temperature sensitivity are mediated by the ribosome binding domain. In addition, the sequence of the first translated codon is also an important determinant of IRES activity. Our findings provide us with a comprehensive overview of IGR IRES activities and allow us to begin to understand the differences between Classes I and II IGR IRESs.

Hertz, Marla I.; Thompson, Sunnie R.

2011-01-01

242

In vivo function of Tic22, a protein import component of the intermembrane space of chloroplasts.  

PubMed

Preprotein import into chloroplasts depends on macromolecular machineries in the outer and inner chloroplast envelope membrane (TOC and TIC). It was suggested that both machineries are interconnected by components of the intermembrane space (IMS). That is, amongst others, Tic22, of which two closely related isoforms exist in Arabidopsis thaliana, namely atTic22-III and atTic22-IV. We investigated the function of Tic22 in vivo by analyzing T-DNA insertion lines of the corresponding genes. While the T-DNA insertion in the individual genes caused only slight defects, a double mutant of both isoforms showed retarded growth, a pale phenotype under high-light conditions, a reduced import rate, and a reduction in the photosynthetic performance of the plants. The latter is supported by changes in the metabolite content of mutant plants when compared to wild-type. Thus, our results support the notion that Tic22 is directly involved in chloroplast preprotein import and might point to a particular importance of Tic22 in chloroplast biogenesis at times of high import rates. PMID:23204504

Rudolf, Mareike; Machettira, Anu B; Groß, Lucia E; Weber, Katrin L; Bolte, Kathrin; Bionda, Tihana; Sommer, Maik S; Maier, Uwe G; Weber, Andreas P M; Schleiff, Enrico; Tripp, Joanna

2012-11-30

243

In vivo and in vitro effects of 1,1-dimethylhydrazine on selected immune functions.  

PubMed

The in vivo phase of the experiments reported here include the evaluation of immune function after short-or long-term treatment of mice with 1,1-dimethylhydrazine (UDMH). Long-term exposure (3 injections/week for 14 weeks) resulted in increased numbers of Jerne plaque-forming cells, a trend toward decreased induction of suppressor cell activity by concanavalin A (Con A), and no effects on mitogen-induced lymphocyte blast transformation (LBT), compared to saline-treated control mice. These effects were greatest at doses of 10 or 50 mg/kg, while higher doses had less of an effect. In vitro experiments were performed by adding UDMH to normal murine splenocytes in the LBT assay and con A-induced suppressor cell assay. The UDMH induced a significant enhanced response to lipopolysaccharide (LPS) at 10 and 50 micrograms/ml, and a suppressed response to both Con A and LPS at higher concentrations. The UDMH also caused a decrease in suppressor cell activity at 25 micrograms/ml. Selective abrogation of suppressor activity or alteration of the suppressor cell-helper ratio were suggested as possible mechanisms for the enhancement effect associated with UDMH. PMID:6211418

Tarr, M J; Olsen, R G; Jacobs, D L

1982-04-01

244

In vivo analysis of the functional domains of the Drosophila splicing regulator RBP1  

PubMed Central

The Drosophila splicing factor RBP1 participates together with TRA and TRA-2 in the regulation of alternative splicing of doublesex (dsx) pre-mRNA. It does so by recognizing RBP1 RNA target sequences in the dsx pre-mRNA. RBP1 belongs to the Ser–Arg-rich (SR) protein family of splicing factors, which have in common a N-terminal RNA recognition motif-type RNA binding domain, a Gly-rich region, and a C-terminal SR domain. Using a tissue culture transfection assay, we demonstrate that the Gly residues within the Gly-rich domain, the ribonucleoprotein motifs within the RNA recognition motif RNA binding domain, and the SR domain are required for regulation of dsx splicing by RBP1 in vivo. Furthermore, using a two-hybrid system, we show protein–protein interactions between RBP1 and itself and between RBP1 and TRA-2. The SR domain and the Gly residues within the Gly-rich domain of RBP1 were found to be involved in these protein–protein interactions. Our results suggest that RBP1 and TRA-2 function in regulation of dsx splicing by forming a complex.

Heinrichs, Volker; Baker, Bruce S.

1997-01-01

245

3'-untranslated regions of oxidative phosphorylation mRNAs function in vivo as enhancers of translation.  

PubMed Central

Recent findings have indicated that the 3'-untranslated region (3'-UTR) of the mRNA encoding the beta-catalytic subunit of the mitochondrial H(+)-ATP synthase has an in vitro translation-enhancing activity (TEA) [Izquierdo and Cuezva, Mol. Cell. Biol. (1997) 17, 5255-5268; Izquierdo and Cuezva, Biochem. J. (2000) 346, 849-855]. In the present work, we have expressed chimaeric plasmids that encode mRNA variants of green fluorescent protein in normal rat kidney and liver clone 9 cells to determine whether the 3'-UTRs of nuclear-encoded mRNAs involved in the biogenesis of mitochondria have an intrinsic TEA. TEA is found in the 3'-UTR of the mRNAs encoding the alpha- and beta-subunits of the rat H(+)-ATP synthase complex, as well as in subunit IV of cytochrome c oxidase. No TEA is present in the 3'-UTR of the somatic mRNA encoding rat mitochondrial transcription factor A. Interestingly, the TEA of the 3'-UTR of mRNAs of oxidative phosphorylation is different, depending upon the cell type analysed. These data provide the first in vivo evidence of a novel cell-specific mechanism for the control of the translation of mRNAs required in mitochondrial function.

Di Liegro, C M; Bellafiore, M; Izquierdo, J M; Rantanen, A; Cuezva, J M

2000-01-01

246

A covalent tandem dimer of the mitochondrial ADP/ATP carrier is functional in vivo.  

PubMed

The adenine nucleotide carrier, or Ancp, is an integral protein of the inner mitochondrial membrane. It is established that the inactive Ancp bound to one of its inhibitors (CATR or BA) is a dimer, but different contradictory models were proposed over the past years to describe the organization of the active Ancp. In order to decide in favor of a single model, it is necessary to establish the orientations of the N- and C-termini and thus the parity of the Ancp transmembrane segments (TMS). According to this, we have constructed a gene encoding a covalent tandem dimer of the Saccharomyces cerevisiae Anc2p and we demonstrate that it is stable and active in vivo as well as in vitro. The properties of the isolated dimer are strongly similar to those of the native Anc2p, as seen from nucleotide exchange and inhibitor binding experiments. We can therefore conclude that the native Anc2p has an even number of TMS and that the N- and C-terminal regions are exposed to the same cellular compartment. Furthermore, our results support the idea of a minimal dimeric functional organization of the Ancp in the mitochondrial membrane and we can suggest that TMS 1 of one monomer and TMS 6 of the other monomer in the native dimer are very close to each other. PMID:10692552

Trézéguet, V; Le Saux, A; David, C; Gourdet, C; Fiore, C; Dianoux, A; Brandolin, G; Lauquin, G J

2000-02-24

247

Identification and functional characterization in vivo of a novel splice variant of LDLR in rhesus macaques.  

PubMed

In the course of developing a low-density lipoprotein receptor (LDLR) gene therapy treatment for homozygous familial hypercholesterolemia (HoFH), we planned to examine the efficacy in a nonhuman primate model, the rhesus macaque heterozygous for an LDL receptor mutation fed a high-fat diet. Unexpectedly, our initial cDNA sequencing studies led to the identification of a heretofore unidentified splicing isoform of the rhesus LDLR gene. Compared with the publicly available GenBank reference sequence of rhesus LDLR, the novel isoform contains a 21 bp in frame insertion. This sequence coincides with part of exon 5 and creates a site for the restriction enzyme MscI. Using this site as a marker for the 21 bp in-frame insertion, we conducted a restriction enzyme screen to examine for the prevalence of the novel isoform in rhesus liver tissue cDNA and its homolog in human liver tissue cDNA. We found that the novel isoform is the predominant LDLR cDNA found in rhesus liver and the sole LDLR cDNA found in human liver. Finally, we compared the in vivo functionality of the novel and previously identified rhesus LDLR splicing isoforms in a mouse model of HoFH. PMID:21628398

Kassim, Sadik H; Vandenberghe, Luk H; Hovhannisyan, Ruben; Wilson, James M; Rader, Daniel J

2011-05-31

248

The proximal element of the beta globin locus control region is not functionally required in vivo.  

PubMed Central

In addition to local sequence elements the regulation of the high-level, development- and tissue-specific expression of the human beta globin gene cluster appears to require distant regulatory sequences which have been termed locus control region. In the chromatin of erythroid cells the locus control region is characterized by four DNaseI hypersensitive sites that are located 6-18 kb 5' of the epsilon globin gene. The definition of the sequences minimally required for locus control region activity is likely to further the understanding of its physiology and will be of interest for the development of somatic gene therapy strategies of the hemoglobinopathies. We present here the analysis of a family with a 3,030-bp deletion of sequences upstream of the epsilon globin gene including the most 3' locus control region element and cosegregating beta(0) thalassemia. The deletion is linked in cis to a structurally and functionally normal beta globin gene. The proximal element of the locus control region does not therefore appear to be necessary for beta globin gene activity in vivo. Images

Kulozik, A E; Bail, S; Bellan-Koch, A; Bartram, C R; Kohne, E; Kleihauer, E

1991-01-01

249

[In vivo studies of the main functional systems in the heteronemertean pilidium larva].  

PubMed

There is performed in vivo morphological study of the White Sea heteronemerteans belonging to the type of pilidium pyramidale (conussoidale). Based on the layer-by-layer microshooting with subsequent computer processing, development of the pilidium digestive, nervous, and muscle systems is described from the stage following at once the gastrula to the premetamorphose larva. Peculiarities of structural organization of the main functional systems are revealed depending on the larva size and the stage of formation of imaginal discs. It is first shown that even in the not completely formed pilidium, neurons are located not only in integuments and wall of the digestive tract, but also in the depth of cupola along the central muscle retractor. Their processes are distributed between the main body parts and organs by seeming to perform connections of the apical organ and central muscle retractor with the digestive tract, blades, and the nerve plexus of the cupola wall. In the digestive tract between pharynx and stomach in the formed pilidium, the sphincter is first revealed. It has been shown that in the course of larva development, the non-orderly arranged and poorly developed muscle fibers gradually form in the blade the fan-like, whereas in the cupola wall, the net-like structure. PMID:20799611

Za?tseva, O V; Fliachinskaia, L P

250

In vivo functional and myeloarchitectonic mapping of human primary auditory areas  

PubMed Central

In contrast to vision, where retinotopic mapping alone can define areal borders, primary auditory areas such as A1 are best delineated by combining in vivo tonotopic mapping with post mortem cyto- or myelo-architectonics from the same individual. We combined high-resolution (800 ?m) quantitative T1 mapping with phase-encoded tonotopic methods to map primary auditory areas (A1 and R) within the ‘auditory core’ of human volunteers. We first quantitatively characterize the highly myelinated auditory core in terms of shape, area, cortical depth profile, and position, with our data showing considerable correspondence to post-mortem myeloarchitectonic studies, both in cross-participant averages and in individuals. The core region contains two ‘mirror-image‘ tonotopic maps oriented along the same axis as observed in macaque and owl monkey. We suggest that thee two maps within the core are the human analogues of primate auditory areas A1 and R. The core occupies a much smaller portion of tonotopically organized cortex on the superior temporal plane and gyrus than is generally supposed. The multi-modal approach to defining the auditory core will facilitate investigations of structure-function relationships, comparative neuroanatomical studies, and promises new biomarkers for diagnosis and clinical studies.

Dick, Frederic; Tierney, Adam Taylor; Lutti, Antoine; Josephs, Oliver; Sereno, Martin I.; Weiskopf, Nikolaus

2012-01-01

251

Hypermethylation of HOXA10 gene in mid-luteal endometrium from women with ovarian endometriomas.  

PubMed

A decrease in HOXA10 gene expression in eutopic mid-secretory endometrium has been found in women with endometriosis-associated infertility. Promoter hypermethylation of HOXA10 is thought to be the leading mechanism for epigenetic gene regulation in patients with endometriosis. In our series we documented significantly higher HOXA10 promoter methylation levels in women with ovarian endometriomas than in healthy controls during the mid-luteal phase. Development of epigenetic-based strategies for non-surgical treatment of infertility related to ovarian endometriomas could be an attractive field of research in the coming years. PMID:24032603

Fambrini, Massimiliano; Sorbi, Flavia; Bussani, Cecilia; Cioni, Riccardo; Sisti, Giovanni; Andersson, Karin L

2013-09-11

252

In vitro gene regulatory networks predict in vivo function of liver  

Microsoft Academic Search

BACKGROUND: Evolution of toxicity testing is predicated upon using in vitro cell based systems to rapidly screen and predict how a chemical might cause toxicity to an organ in vivo. However, the degree to which we can extend in vitro results to in vivo activity and possible mechanisms of action remains to be fully addressed. RESULTS: Here we use the

Youping Deng; David R Johnson; Xin Guan; Choo Y Ang; Junmei Ai; Edward J Perkins

2010-01-01

253

Exposure to low mercury concentration in vivo impairs myocardial contractile function  

SciTech Connect

Increased cardiovascular risk after mercury exposure has been described but cardiac effects resulting from controlled chronic treatment are not yet well explored. We analyzed the effects of chronic exposure to low mercury concentrations on hemodynamic and ventricular function of isolated hearts. Wistar rats were treated with HgCl{sub 2} (1st dose 4.6 {mu}g/kg, subsequent dose 0.07 {mu}g/kg/day, im, 30 days) or vehicle. Mercury treatment did not affect blood pressure (BP) nor produced cardiac hypertrophy or changes of myocyte morphometry and collagen content. This treatment: 1) in vivo increased left ventricle end diastolic pressure (LVEDP) without changing left ventricular systolic pressure (LVSP) and heart rate; 2) in isolated hearts reduced LV isovolumic systolic pressure and time derivatives, and {beta}-adrenergic response; 3) increased myosin ATPase activity; 4) reduced Na{sup +}-K{sup +} ATPase (NKA) activity; 5) reduced protein expression of SERCA and phosphorylated phospholamban on serine 16 while phospholamban expression increased; as a consequence SERCA/phospholamban ratio reduced; 6) reduced sodium/calcium exchanger (NCX) protein expression and {alpha}-1 isoform of NKA, whereas {alpha}-2 isoform of NKA did not change. Chronic exposure for 30 days to low concentrations of mercury does not change BP, heart rate or LVSP but produces small but significant increase of LVEDP. However, in isolated hearts mercury treatment promoted contractility dysfunction as a result of the decreased NKA activity, reduction of NCX and SERCA and increased PLB protein expression. These findings offer further evidence that mercury chronic exposure, even at small concentrations, is an environmental risk factor affecting heart function. - Highlights: > Unchanges blood pressure, heart rate, systolic pressure. > Increases end diastolic pressure. > Promotes cardiac contractility dysfunction. > Decreases NKA activity, NCX and SERCA, increases PLB protein expression. > Small concentrations constitutes environmental cardiovascular risk factor.

Furieri, Lorena Barros; Fioresi, Mirian; Junior, Rogerio Faustino Ribeiro [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Bartolome, Maria Visitacion [Department of Physiology, Universidad Complutense de Madrid (Spain); Fernandes, Aurelia Araujo [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Cachofeiro, Victoria; Lahera, Vicente [Department of Physiology, Universidad Complutense de Madrid (Spain); Salaices, Mercedes [Department of Pharmacology, Universidad Autonoma de Madrid (Spain); Stefanon, Ivanita [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Vassallo, Dalton Valentim, E-mail: daltonv2@terra.com.br [Department of Physiological Sciences, Federal University of Espirito Santo, Vitoria, ES (Brazil); Health Science Center of Vitoria-EMESCAM, Vitoria, ES (Brazil)

2011-09-01

254

In vivo analysis of p53 tumor suppressor function using genetically engineered mouse models  

PubMed Central

p53 is a crucial tumor suppressor, as evidenced by the high propensity for p53 mutation during human cancer development. Already more than a decade ago, p53 knockout mice confirmed that p53 is critical for preventing tumorigenesis. More recently, a host of p53 knock-in mouse strains has been generated, with the aim of either more precisely modeling p53 mutations in human cancer or better understanding p53's regulation and downstream activities. In the first category, several mouse strains expressing mutant p53 proteins corresponding to human-tumor-derived mutants have demonstrated that mutant p53 is not equivalent to loss of p53 but additionally exhibits gain-of-function properties, promoting invasive and metastatic phenotypes. The second class of p53 knock-in mouse models expressing engineered p53 mutants has also provided new insight into p53 function. For example, mice expressing p53 mutants lacking specific posttranslational modification sites have revealed that these modifications serve to modulate p53 responses in vivo in a cell-type- and stress-specific manner rather than being absolutely required for p53 stabilization and activation as suggested by in vitro experiments. Additionally, studies of p53 mouse models have established that both p53-driven cell-cycle arrest and apoptosis responses contribute to tumor suppression and that activation of p53 by oncogenic stress imposes an important barrier to tumorigenesis. Finally, the use of mouse strains expressing temporally regulatable p53 has demonstrated that p53 loss is not only required for tumor development but also required for tumor maintenance, suggesting that p53 restoration in human cancer patients may be a promising therapeutic strategy. These sophisticated p53 mouse models have taught us important lessons, and new mouse models will certainly continue to reveal interesting and perhaps surprising aspects of p53's complex biology.

Broz, Daniela Kenzelmann; Attardi, Laura D.

2010-01-01

255

Nobiletin, a citrus polymethoxyflavonoid, suppresses multiple angiogenesis-related endothelial cell functions and angiogenesis in vivo.  

PubMed

Nobiletin is a citrus polymethoxyflavonoid that suppresses tumor growth and metastasis, both of which depend on angiogenesis. We recently identified nobiletin as a cell differentiation modulator. Because cell differentiation is a critical event in angiogenesis, it might be possible that nobiletin could exhibit antiangiogenic activity, resulting in suppression of these tumor malignant properties. To verify this possibility, we examined the antiangiogenic effects of nobiletin in vitro and in vivo. Nobiletin had concentration-dependent inhibitory effects on multiple functions of angiogenesis-related endothelial cells (EC); it suppressed the proliferation, migration and tube formation on matrigel of human umbilical vein EC (HUVEC) stimulated with endothelial cell growth supplement (ECGS), a mixture of acidic and basic fibroblast growth factors (FGFs). Gelatin zymography and northern blotting revealed that nobiletin suppressed pro-matrix metalloproteinase-2 (proMMP-2) production and MMP-2 mRNA expression in ECGS-stimulated HUVEC. Nobiletin also downregulated cell-associated plasminogen activator (PA) activity and urokinase-type PA mRNA expression. Furthermore, nobiletin inhibited angiogenic differentiation induced by vascular endothelial growth factor and FGF, an in vitro angiogenesis model. This inhibition was accompanied by downregulation of angiogenesis-related signaling molecules, such as extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase, and transcriptional factors (c-Jun and signal transducer and activator of transcription 3), and activation of the caspase pathway. In a chick embryo chorioallantoic membrane assay, nobiletin showed an antiangiogenic activity, the ID(50) value being 10?g (24.9nmol) per egg. These results indicate that nobiletin is a novel antiangiogenic compound that exhibits its activity through combined inhibition of multiple angiogenic EC functions. PMID:20670297

Kunimasa, Kazuhiro; Ikekita, Masahiko; Sato, Mayumi; Ohta, Toshiro; Yamori, Yukio; Ikeda, Megumi; Kuranuki, Sachi; Oikawa, Tsutomu

2010-11-01

256

In vivo coassembly of a divergent beta-tubulin subunit (c beta 6) into microtubules of different function  

PubMed Central

alpha- and beta-Tubulin are encoded in vertebrate genomes by a family of approximately 6-7 functional genes whose polypeptide products differ in amino acid sequence. In the chicken, one beta-tubulin isotype (c beta 6) has previously been found to be expressed only in thrombocytes and erythroid cells, where it is assembled into a circumferential ring of marginal band microtubules. In light of its unique in vivo utilization and its divergent assembly properties in vitro, we used DNA transfection to test whether this isotype could be assembled in vivo into microtubules of divergent functions. Using an antibody specific to c beta 6, we have found that upon transfection this polypeptide is freely coassembled into an extensive array of interphase cytoplasmic microtubules and into astral and pole-to-chromosome or pole-to-pole microtubules during mitosis. Further, examination of developing chicken erythrocytes reveals that both beta-tubulins that are expressed in these cells (c beta 6 and c beta 3) are found as co-polymers of the two isoforms. These results, in conjunction with efforts that have localized various other beta-tubulin isotypes, demonstrate that to the resolution limit afforded by light microscopy in vivo microtubules in vertebrates are random copolymers of available isotypes. Although these findings are consistent with functional interchangeability of beta- tubulin isotypes, we have also found that in vivo microtubules enriched in c beta 3 polypeptides are more sensitive to cold depolymerization than those enriched in c beta 6. This differential quantitative utilization of the two endogenous isotypes documents that some in vivo functional differences between isotypes do exist.

1987-01-01

257

Maternal separation affects dopamine transporter function in the Spontaneously Hypertensive Rat: An in vivo electrochemical study  

PubMed Central

Background Attention-deficit/hyperactivity disorder (ADHD) is a developmental disorder characterised by symptoms of inattention, impulsivity and hyperactivity. The spontaneously hypertensive rat (SHR) is a well-characterised model of this disorder and has been shown to exhibit dopamine dysregulation, one of the hypothesised causes of ADHD. Since stress experienced in the early stages of life can have long-lasting effects on behaviour, it was considered that early life stress may alter development of the dopaminergic system and thereby contribute to the behavioural characteristics of SHR. It was hypothesized that maternal separation would alter dopamine regulation by the transporter (DAT) in ways that distinguish SHR from control rat strains. Methods SHR and control Wistar-Kyoto (WKY) rats were subjected to maternal separation for 3 hours per day from postnatal day 2 to 14. Rats were tested for separation-induced anxiety-like behaviour followed by in vivo chronoamperometry to determine whether changes had occurred in striatal clearance of dopamine by DAT. The rate of disappearance of ejected dopamine was used as a measure of DAT function. Results Consistent with a model for ADHD, SHR were more active than WKY in the open field. SHR entered the inner zone more frequently and covered a significantly greater distance than WKY. Maternal separation increased the time that WKY spent in the closed arms and latency to enter the open arms of the elevated plus maze, consistent with other rat strains. Of note is that, maternal separation failed to produce anxiety-like behaviour in SHR. Analysis of the chronoamperometric data revealed that there was no difference in DAT function in the striatum of non-separated SHR and WKY. Maternal separation decreased the rate of dopamine clearance (k-1) in SHR striatum. Consistent with this observation, the dopamine clearance time (T100) was increased in SHR. These results suggest that the chronic mild stress of maternal separation impaired the function of striatal DAT in SHR. Conclusions The present findings suggest that maternal separation failed to alter the behaviour of SHR in the open field and elevated plus maze. However, maternal separation altered the dopaminergic system by decreasing surface expression of DAT and/or the affinity of DAT for dopamine, increasing the time to clear dopamine from the extracellular fluid in the striatum of SHR.

2011-01-01

258

Application of Electrical Stimulation for Functional Tissue Engineering In Vitro and In Vivo.  

National Technical Information Service (NTIS)

The present invention provides new methods for the in vitro preparation of bioartificial tissue equivalents and their enhanced integration after implantation in vivo. These methods include submitting a tissue construct to a biomimetic electrical stimulati...

G. V. Novakovic H. Park L. Freed M. Radisic R. Langer

2004-01-01

259

In vivo function of airway epithelial TLR2 in host defense against bacterial infection  

PubMed Central

Decreased Toll-like receptor 2 (TLR2) expression has been reported in patients with chronic obstructive pulmonary disease and in a murine asthma model, which may predispose the hosts to bacterial infections, leading to disease exacerbations. Since airway epithelial cells serve as the first line of respiratory mucosal defense, the present study aimed to reveal the role of airway epithelial TLR2 signaling to lung bacterial [i.e., Mycoplasma pneumoniae (Mp)] clearance. In vivo TLR2 gene transfer via intranasal inoculation of adenoviral vector was performed to reconstitute TLR2 expression in airway epithelium of TLR2?/? BALB/c mice, with or without ensuing Mp infection. TLR2 and lactotransferrin (LTF) expression in airway epithelial cells and lung Mp load were assessed. Adenovirus-mediated TLR2 gene transfer to airway epithelial cells of TLR2?/? mice reconstituted 30–40% TLR2 expression compared with TLR2+/+ cells. Such airway epithelial TLR2 reconstitution in TLR2?/? mice significantly reduced lung Mp load (an appropriate 45% reduction), coupled with elevated LTF expression. LTF expression in mice was shown to be mainly dependent on TLR2 signaling in response to Mp infection. Exogenous human LTF protein dose-dependently decreased lung bacterial load in Mp-infected TLR2?/? mice. In addition, human LTF protein directly dose-dependently decreased Mp levels in vitro. These data indicate that reconstitution of airway epithelial TLR2 signaling in TLR2?/? mice significantly restores lung defense against bacteria (e.g., Mp) via increased lung antimicrobial protein LTF production. Our findings may offer a deliverable approach to attenuate bacterial infections in airways of asthma or chronic obstructive pulmonary disease patients with impaired TLR2 function.

Wu, Qun; Jiang, Di; Minor, Maisha N.; Martin, Richard J.

2011-01-01

260

A Surface Groove Essential for Viral Bcl-2 Function During Chronic Infection In Vivo  

PubMed Central

Antiapoptotic Bcl-2 family proteins inhibit apoptosis in cultured cells by binding BH3 domains of proapoptotic Bcl-2 family members via a hydrophobic BH3 binding groove on the protein surface. We investigated the physiological importance of the BH3 binding groove of an antiapoptotic Bcl-2 protein in mammals in vivo by analyzing a viral Bcl-2 family protein. We show that the ?-herpesvirus 68 (?HV68) Bcl-2 family protein (?HV68 v-Bcl-2), which is known to inhibit apoptosis in cultured cells, inhibits both apoptosis in primary lymphocytes and Bax toxicity in yeast. Nuclear magnetic resonance determination of the ?HV68 v-Bcl-2 structure revealed a BH3 binding groove that binds BH3 domain peptides from proapoptotic Bcl-2 family members Bax and Bak via a molecular mechanism shared with host Bcl-2 family proteins, involving a conserved arginine in the BH3 peptide binding groove. Mutations of this conserved arginine and two adjacent amino acids to alanine (SGR to AAA) within the BH3 binding groove resulted in a properly folded protein that lacked the capacity of the wild-type ?HV68 v-Bcl-2 to bind Bax BH3 peptide and to block Bax toxicity in yeast. We tested the physiological importance of this v-Bcl-2 domain during viral infection by engineering viral mutants encoding a v-Bcl-2 containing the SGR to AAA mutation. This mutation resulted in a virus defective for both efficient reactivation of ?HV68 from latency and efficient persistent ?HV68 replication. These studies demonstrate an essential functional role for amino acids in the BH3 peptide binding groove of a viral Bcl-2 family member during chronic infection.

Petros, Andrew M; Nettesheim, David; van Dyk, Linda F.; Labrada, Lucia; Speck, Samuel H; Levine, Beth

2005-01-01

261

Effect of in vivo chronic exposure to clotrimazole on zebrafish testis function.  

PubMed

Clotrimazole is an azole fungicide used as a human pharmaceutical that is known to inhibit cytochrome P450 (CYP) enzymatic activities, including several steroidogenic CYP. In a previous report, we showed that a 7-day exposure to clotrimazole induced the expression of genes related to steroidogenesis in the testes as a compensatory response, involving the activation of the Fsh/Fshr pathway. In this context, the aim of the present study was to assess the effect of an in vivo 21-day chronic exposure to clotrimazole (30-197 ?g/L) on zebrafish testis function, i.e., spermatogenesis and androgen release. The experimental design combined (1) gene transcript levels measurements along the brain-pituitary-gonad axis, (2) 11-ketotestosterone (11-KT) quantification in the blood, and (3) histology of the testes, including morphometric analysis. The chronic exposure led to an induction of steroidogenesis-related genes and fshr in the testes as well as fsh? in the pituitary. Moreover, increases of the gonadosomatic index and of the volume proportion of interstitial Leydig cells were observed in clotrimazole-exposed fish. In accordance with these histological observations, the circulating concentration of 11-KT had increased. Morphometric analysis of the testes did not show an effect of clotrimazole on meiotic (spermatocytes) or postmeiotic (spermatids and spermatozoa) stages, but we observed an increase in the number of type A spermatogonia, in agreement with an increase in mRNA levels of piwil1, a specific molecular marker of type A spermatogonia. Our study demonstrated that clotrimazole is able to affect testicular physiology and raised further concern about the impact of clotrimazole on reproduction. PMID:23340899

Baudiffier, Damien; Hinfray, Nathalie; Ravaud, Catherine; Creusot, Nicolas; Chadili, Edith; Porcher, Jean-Marc; Schulz, Rüdiger W; Brion, François

2013-01-23

262

In vivo functional assay of a recombinant aquaporin in Pichia pastoris.  

PubMed

The water channel protein PvTIP3;1 (alpha-TIP) is a member of the major intrinsic protein (MIP) membrane channel family. We overexpressed this eukaryotic aquaporin in the methylotrophic yeast Pichia pastoris, and immunogold labeling of cellular cryosections showed that the protein accumulated in the plasma membrane, as well as vacuolar and other intracellular membranes. We then developed an in vivo functional assay for water channel activity that measures the change in optical absorbance of spheroplasts following an osmotic shock. Spheroplasts of wild-type P. pastoris displayed a linear relationship between absorbance and osmotic shock level. However, spheroplasts of P. pastoris expressing PvTIP3;1 showed a break in this linear relationship corresponding to hypo-osmotically induced lysis. It is the difference between control and transformed spheroplasts under conditions of hypo-osmotic shock that forms the basis of our aquaporin activity assay. The aquaporin inhibitor mercury chloride blocked water channel activity but had no effect on wild-type yeast. Osmotically shocked yeast cells were affected only slightly by expression of the Escherichia coli glycerol channel GlpF, which belongs to the MIP family but is a weak water channel. The important role that aquaporins play in human physiology has led to a growing interest in their potential as drug targets for treatment of hypertension and congestive heart failure, as well as other fluid overload states. The simplicity of this assay that is specific for water channel activity should enable rapid screening for compounds that modulate water channel activity. PMID:16461705

Daniels, Mark J; Wood, Malcolm R; Yeager, Mark

2006-02-01

263

SAHA Enhances Synaptic Function and Plasticity In Vitro but Has Limited Brain Availability In Vivo and Does Not Impact Cognition  

PubMed Central

Suberoylanilide hydroxamic acid (SAHA) is an inhibitor of histone deacetylases (HDACs) used for the treatment of cutaneous T cell lymphoma (CTCL) and under consideration for other indications. In vivo studies suggest reducing HDAC function can enhance synaptic function and memory, raising the possibility that SAHA treatment could have neurological benefits. We first examined the impacts of SAHA on synaptic function in vitro using rat organotypic hippocampal brain slices. Following several days of SAHA treatment, basal excitatory but not inhibitory synaptic function was enhanced. Presynaptic release probability and intrinsic neuronal excitability were unaffected suggesting SAHA treatment selectively enhanced postsynaptic excitatory function. In addition, long-term potentiation (LTP) of excitatory synapses was augmented, while long-term depression (LTD) was impaired in SAHA treated slices. Despite the in vitro synaptic enhancements, in vivo SAHA treatment did not rescue memory deficits in the Tg2576 mouse model of Alzheimer’s disease (AD). Along with the lack of behavioral impact, pharmacokinetic analysis indicated poor brain availability of SAHA. Broader assessment of in vivo SAHA treatment using high-content phenotypic characterization of C57Bl6 mice failed to demonstrate significant behavioral effects of up to 150 mg/kg SAHA following either acute or chronic injections. Potentially explaining the low brain exposure and lack of behavioral impacts, SAHA was found to be a substrate of the blood brain barrier (BBB) efflux transporters Pgp and Bcrp1. Thus while our in vitro data show that HDAC inhibition can enhance excitatory synaptic strength and potentiation, our in vivo data suggests limited brain availability may contribute to the lack of behavioral impact of SAHA following peripheral delivery. These results do not predict CNS effects of SAHA during clinical use and also emphasize the importance of analyzing brain drug levels when interpreting preclinical behavioral pharmacology.

Hanson, Jesse E.; La, Hank; Plise, Emile; Chen, Yung-Hsiang; Ding, Xiao; Hanania, Taleen; Sabath, Emily V.; Alexandrov, Vadim; Brunner, Dani; Leahy, Emer; Steiner, Pascal; Liu, Lichuan; Scearce-Levie, Kimberly; Zhou, Qiang

2013-01-01

264

Exposure-in-vivo containing interventions to improve work functioning of workers with anxiety disorder: a systematic review  

PubMed Central

Background Anxiety disorders are associated with functional disability, sickness absence, and decreased productivity. Effective treatments of anxiety disorders can result in remission of symptoms. However the effects on work related outcomes are largely unknown. Exposure in vivo is potentially well fit to improve work-related outcomes. This study systematically reviews the effectiveness of exposure-in-vivo containing interventions in reducing work-related adverse outcomes in workers with anxiety disorders. Methods A systematic study search was conducted in Medline, Cinahl, Embase and Psycinfo. Two reviewers independently extracted data and from each study assessed the quality of evidence by using the GRADE approach. We performed a meta-analysis if data showed sufficient clinical homogeneity. Results Seven studies containing 11 exposure-in-vivo interventions were included. Four studies were focused on Obsessive Compulsive Disorder (OCD), two on Post Traumatic Stress Disorder (PTSD), and one on a mixed group of OCD and severe phobias. The studies were grouped according to type of anxiety disorder and subsequently according to type of comparisons. For OCD, exposure-in-vivo containing interventions can yield better work-related outcomes compared to medication (SSRIs) and relaxation but not better compared to response prevention. The results on anxiety outcomes were similar. The net contribution of exposure in vivo in two OCD intervention programs is also presented as a meta-analysis and shows significant positive results on work role limitations. The calculated pooled effect size with 95% confidence interval was 0.72 (0.28, 1.15). For PTSD, exposure-in-vivo containing interventions can yield better work-related and anxiety-related outcomes compared to a waiting-list but not better compared to imaginal exposure. Conclusions Exposure in vivo as part of an anxiety treatment can reduce work-related adverse outcomes in workers with OCD and PTSD better than various other anxiety treatments or a waiting-list. We recommend that it should be studied how the results of these studies can be transferred to the practice of occupational health professionals and how clinicians can make better use of them to improve work-related outcomes. In future research, priority should be given to high-quality randomised controlled trials (RCTs) in which exposure-in-vivo containing interventions are applied to a variety of anxiety disorders and compared with other clinical anxiety treatments such as SSRIs. Work-related outcomes, in particular work functioning and sickness absence, need to be assessed with reliable and valid measures.

2010-01-01

265

First in vivo evidence for a functional interaction between chemokine and cannabinoid systems in the brain.  

PubMed

Growing evidence supports the idea that in addition to their well established role in the immune system, chemokines might play a role in both normal and pathological brain function, and the chemokine network could interact with other neuromodulators. The chemokine stromal cell-derived growth factor (SDF)-1alpha/CXCL12, a member of the CXC chemokine family, was tested for its possible effect on the analgesic responses of the cannabinoid receptor agonist aminoalkylindole 4,5-dihydro-2-methyl-4-(4-morpholinylmethyl)-1-(1-naphthalenyl-carbonyl)-6H-pyrrolo-[3,2,1ij]quinolin-6-one [(+)-WIN 55,212-2, hereafter WIN 55,212-2] at the level of the periaqueductal gray (PAG), a brain region critical to the processing of pain signals, and a primary site of action of many analgesic compounds. The administration of WIN 55,212-2 (0.1-0.4 microg/microl) into the PAG resulted in antinociception in a dose-dependent manner. The selective cannabinoid (CB)1 antagonist N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide hydrochloride (SR 141716A; 1-10 microg) given into the PAG blocked the WIN 55,212-2-induced antinociception. In contrast, the selective CB2 antagonist N-[(1S)-endo-1,3,3-trimethyl bicyclo heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide (SR144528; 10 microg) did not alter the WIN 55,212-2-induced antinociception. Pretreatment with SDF-1alpha/CXCL12 (100 ng) caused a reduction in antinociceptive responses of WIN 55,212-2. The inhibitory effect of SDF-1alpha/CXCL12 on WIN 55,212-2-induced antinociception was reversed by octahydrochloride [corrected] hydrate (AMD 3100) (10-50 ng), an antagonist of the SDF-1alpha/CXCL12, acting at its receptor, CXCR4. This study reports the first in vivo evidence of a functional interaction between chemokine and cannabinoid systems in the brain, showing that the activation of SDF-1alpha/CXCL12 receptors (CXCR4) in the PAG interferes with the analgesic effects of WIN 55212-2. PMID:18281594

Benamar, Khalid; Geller, Ellen B; Adler, Martin W

2008-02-15

266

Protective effect of trimetazidine on myocardial mitochondrial function in an ex-vivo model of global myocardial ischemia  

Microsoft Academic Search

Trimetazidine is an anti-ischemic drug whose cytoprotective mechanisms are not yet fully understood (but until now mainly related to the trimetazidine-induced “metabolic shift” from lipid ?-oxidation to glucose aerobic oxidation). We studied the effect of trimetazidine on the mitochondrial function of ischemic Wistar rat hearts perfused with glucose, using a model of ex-vivo perfusion (Langendorff system). We measured the electrical

Pedro Monteiro; Ana I. Duarte; Lino M. Gonçalves; António Moreno; Luís A. Providência

2004-01-01

267

In vivo assembly of functional U7 snRNP requires RNA backbone flexibility within the Sm-binding site  

Microsoft Academic Search

Most histone precursor mRNAs (pre-mRNAs) in metazoans are matured by 3?-end cleavage directed by the U7 small nuclear ribonucleoprotein (snRNP). RNA functional groups necessary for in vivo assembly and activity of the U7 snRNP were examined by nucleotide-analog interference mapping and mutagenesis using a chimeric mouse histone H4 pre-mRNA–U7 snRNA construct that is cleaved in cis in Xenopus laevis oocytes.

Nikolay G Kolev; Joan A Steitz

2006-01-01

268

Observations on the use of purified follicle-stimulating hormone in the treatment of luteal phase defects.  

PubMed

We treated 18 infertile patients affected by histologically confirmed luteal phase deficiency with 75 IU of purified follicle-stimulating hormone (FSH) daily during the first 5 days of the cycle. Patients who were not pregnant after the first cycle of treatment underwent a second cycle. In the second cycle the daily doses of purified FSH were doubled if luteal phase deficiency had persisted during the first cycle. During the two cycles before treatment and during treatment, patients underwent an endometrial biopsy 1-3 days before the expected onset of menses. An assessment of progesterone serum concentrations was also performed on days 8, 6 and 4 before the expected onset of menses. Treatment was administered in a total of 33 cycles resulting in 30 ovulatory cycles. Six pregnancies were achieved. Among non-conception ovulatory cycles, 13 presented delayed endometrial dating and 11 normal endometrium. The mean +/- SD of the sum of the three progesterone determinations was 14.7 +/- 1.4 ng/ml in pretreatment cycles, 14.6 +/- 1.6 ng/ml in cycles with normalization of endometrial dating, 14.8 +/- 1.7 ng/ml in cycles with persistence of luteal phase deficiency and 30.4 +/- 3.0 ng/ml in conception cycles (P < 0.05 versus other groups). We conclude that purified FSH, if effective in the treatment of luteal phase deficiency, does not act through an increase in progesterone concentrations. PMID:7593496

Di Carlo, C; Affinito, P; Farace, M J; Gargiulo, A R; Zullo, F; Nappi, C

1995-06-01

269

Randomized controlled trial of the management of premenstrual syndrome and premenstrual mastalgia using luteal phase–only danazol  

Microsoft Academic Search

Objective: Our goal was to evaluate the efficacy and side effects of danazol 200 mg daily given only in the luteal phase of the menstrual cycle to treat premenstrual syndrome and premenstrual mastalgia. Study Design: We conducted a randomized, double-blind, placebo-controlled study of 3 menstrual cycles in a postgraduate medical school and National Health Service hospital. The subjects of the

P. M. Shaughn O'Brien; I. E. H. Abukhalil

1999-01-01

270

Live births after management of severe OHSS by GnRH antagonist administration in the luteal phase  

Microsoft Academic Search

Ovarian hyperstimulation syndrome (OHSS) is a serious complication of ovarian stimulation protocols. Currently, no curative therapy exists and the main preventive option is cycle cancellation. Gonadotrophin-releasing hormone (GnRH) antagonist administration in the luteal phase was recently proposed as a new approach for the management of patients with established severe OHSS. Three polycystic ovarian syndrome patients undergoing IVF treatment developed severe

TG Lainas; IA Sfontouris; IZ Zorzovilis; GK Petsas; GT Lainas; E Alexopoulou; EM Kolibianakis

2009-01-01

271

The impact of luteal phase support on endometrial estrogen and progesterone receptor expression: a randomized control trial  

PubMed Central

Background To assess the impact of luteal phase support on the expression of estrogen receptor (ER) alpha and progesterone receptors B (PR-B) on the endometrium of oocyte donors undergoing controlled ovarian hyperstimulation (COH). Methods A prospective, randomized study was conducted in women undergoing controlled ovarian hyperstimulation for oocyte donation. Participants were randomized to receive no luteal support, vaginal progesterone alone, or vaginal progesterone plus orally administered 17 Beta estradiol. Endometrial biopsies were obtained at 4 time points in the luteal phase and evaluated by tissue microarray for expression of ER alpha and PR-B. Results One-hundred and eight endometrial tissue samples were obtained from 12 patients. No differences were found in expression of ER alpha and PR-B among all the specimens with the exception of one sample value. Conclusions The administration of progesterone during the luteal phase of COH for oocyte donor cycles, either with or without estrogen, does not significantly affect the endometrial expression of ER alpha and PR.

2012-01-01

272

Bone Health Is Not Affected by Luteal Phase Abnormalities and Decreased Ovarian Progesterone Production in Female Runners  

Microsoft Academic Search

The primary purpose of this study was to determine whether de- creased ovarian progesterone production, associated with short and inadequate luteal phases in exercising women, was associated with decreased bone mineral density (BMD) and altered bone metabolism. Thirty-three eumenorrheic menstruating women participated in this study for 3 months. Subjects were required to collect daily urine samples for three consecutive menstrual

MARY JANE DE SOUZA; B. E. MILLER; LISA C. SEQUENZIA; A. A. LUCIANO; S. ULREICH; S. STIER; K. PRESTWOOD; B. L. LASLEY

273

Ex vivo characterization of human CD8+ T subsets with distinct replicative history and partial effector functions.  

PubMed

After antigenic challenge, naive T lymphocytes enter a program of proliferation and differentiation during the course of which they acquire effector functions and may ultimately become memory cells. In humans, the pathways of effector and memory T-cell differentiation remain poorly defined. Here we describe the properties of 2 CD8+ T-lymphocyte subsets, RA+CCR7-27+28+ and RA+CCR7-27+28-, in human peripheral blood. These cells display phenotypic and functional features that are intermediate between naive and effector T cells. Like naive T lymphocytes, both subsets show relatively long telomeres. However, unlike the naive population, these T cells exhibit reduced levels of T-cell receptor excision circles (TRECs), indicating they have undergone additional rounds of in vivo cell division. Furthermore, we show that they also share effector-type properties. At equivalent in vivo replicative history, the 2 subsets express high levels of Fas/CD95 and CD11a, as well as increasing levels of effector mediators such as granzyme B, perforin, interferon gamma, and tumor necrosis factor alpha. Both display partial ex vivo cytolytic activity and can be found among cytomegalovirus-specific cytolytic T cells. Taken together, our data point to the presence of T cells with intermediate effector-like functions and suggest that these subsets consist of T lymphocytes that are evolving toward a more differentiated effector or effector-memory stage. PMID:12750165

Rufer, Nathalie; Zippelius, Alfred; Batard, Pascal; Pittet, Mikael J; Kurth, Isabel; Corthesy, Patricia; Cerottini, Jean-Charles; Leyvraz, Serge; Roosnek, Eddy; Nabholz, Markus; Romero, Pedro

2003-05-15

274

Inhibitory Monoclonal Antibodies against Mouse Proteases Raised in Gene-Deficient Mice Block Proteolytic Functions in vivo  

PubMed Central

Identification of targets for cancer therapy requires the understanding of the in vivo roles of proteins, which can be derived from studies using gene-targeted mice. An alternative strategy is the administration of inhibitory monoclonal antibodies (mAbs), causing acute disruption of the target protein function(s). This approach has the advantage of being a model for therapeutic targeting. mAbs for use in mouse models can be obtained through immunization of gene-deficient mice with the autologous protein. Such mAbs react with both species-specific epitopes and epitopes conserved between species. mAbs against proteins involved in extracellular proteolysis, including plasminogen activators urokinase plasminogen activator (uPA), tissue-type plasminogen activator (tPA), their inhibitor PAI-1, the uPA receptor (uPAR), two matrix metalloproteinases (MMP9 and MMP14), as well as the collagen internalization receptor uPARAP, have been developed. The inhibitory mAbs against uPA and uPAR block plasminogen activation and thereby hepatic fibrinolysis in vivo. Wound healing, another plasmin-dependent process, is delayed by an inhibitory mAb against uPA in the adult mouse. Thromboembolism can be inhibited by anti-PAI-1 mAbs in vivo. In conclusion, function-blocking mAbs are well-suited for targeted therapy in mouse models of different diseases, including cancer.

Lund, Ida K.; Rasch, Morten G.; Ingvarsen, Signe; Pass, Jesper; Madsen, Daniel H.; Engelholm, Lars H.; Behrendt, Niels; H?yer-Hansen, Gunilla

2012-01-01

275

[Vitex agnus castus extract in the treatment of luteal phase defects due to latent hyperprolactinemia. Results of a randomized placebo-controlled double-blind study].  

PubMed

The efficacy of a Vitex agnus castus preparation (Strotan capsules) was investigated in a randomized double blind study vs. placebo. This clinical study involved 52 women with luteal phase defects due to latent hyperprolactinaemia. The daily dose was one capsule (20 mg) Vitex agnus castus preparation and placebo, respectively. Aim of the study was to prove whether the elevated pituitary prolactin reserve can be reduced and deficits in luteal phase length and luteal phase progesterone synthesis be normalized. Blood for hormonal analysis was taken at days 5-8 and day 20 of the menstrual cycle before and after three month of therapy. Latent hyperprolactinaemia was analysed by monitoring the prolactin release 15 and 30 min after i.v. injection of 200 micrograms TRH. 37 complete case reports (placebo: n = 20, verum: n = 17) after 3 month of therapy were statistically evaluated. The prolactin release was reduced after 3 months, shortened luteal phases were normalised and deficits in the luteal progesterone synthesis were eliminated. These changes were significant and occurred only in the verum group. All other hormonal parameters did not change with the exception of 17 beta-estradiol which rouse up in the luteal phase in patients receiving verum. Side effects were not seen, two women treated with the Vitex agnus castus preparation got pregnant. The tested preparation is thought to be an efficient medication in the treatment of luteal phase defects due to latent hyperprolactinaemia. PMID:8369008

Milewicz, A; Gejdel, E; Sworen, H; Sienkiewicz, K; Jedrzejak, J; Teucher, T; Schmitz, H

1993-07-01

276

Beta-blockers, left and right ventricular function, and in-vivo calcium influx in muscular dystrophy cardiomyopathy.  

PubMed

Beta-blockers are used to treat acquired heart failure in adults, though their role in early muscular dystrophy cardiomyopathy is unclear. We treated 2 different dystrophic mouse models which have an associated cardiomyopathy (mdx: model for Duchenne Muscular Dystrophy, and Sgcd-/-: model for limb girdle muscular dystrophy type 2F) and wild type controls (C57 Bl10) with the beta blocker metoprolol or placebo for 8 weeks at an early stage in the development of the cardiomyopathy. Left and right ventricular function was assessed with cardiac magnetic resonance imaging (MRI) and in-vivo myocardial calcium influx with manganese enhanced MRI. In the mdx mice at baseline there was reduced stroke volume, cardiac index, and end-diastolic volume with preserved left ventricular ejection fraction. These abnormalities were no longer evident after treatment with beta-blockers. Right ventricular ejection fraction was reduced and right ventricular end-systolic volume increased in the mdx mice. With metoprolol there was an increase in right ventricular end-diastolic and end-systolic volumes. Left and right ventricular function was normal in the Sgcd-/- mice. Metroprolol had no significant effects on left and right ventricular function in these mice, though heart/body weight ratios increased after treatment. In-vivo myocardial calcium influx with MEMRI was significantly elevated in both models, though metoprolol had no significant effects on either. In conclusion, metoprolol treatment at an early stage in the development of cardiomyopathy has deleterious effects on right ventricular function in mdx mice and in both models no effect on increased in-vivo calcium influx. This suggests that clinical trials need to carefully monitor not just left ventricular function but also right ventricular function and other aspects of myocardial metabolism. PMID:23437355

Blain, Alison; Greally, Elizabeth; Laval, Steve; Blamire, Andrew; Straub, Volker; MacGowan, Guy A

2013-02-20

277

In Vitro and In Vivo Studies of Single-Walled Carbon Nanohorns with Encapsulated Metallofullerenes and Exohedrally Functionalized Quantum Dots  

SciTech Connect

Single-walled carbon nanohorns (SWNHs) are new carbonaceous materials. In this paper, we report the first successful preparation of SWNHs encapsulating trimetallic nitride template endohedral metallofullerenes (TNT-EMFs). The resultant materials were functionalized by a high-speed vibration milling method and conjugated with CdSe/ZnS quantum dots (QDs). The successful encapsulation of TNT-EMFs and external functionalization with QDs provide a dual diagnostic platform for in vitro and in vivo biomedical applications of these new carbonaceous materials.

Zhang, Jianfei [Virginia Polytechnic Institute and State University (Virginia Tech); Ge, Jiechao [Virginia Polytechnic Institute and State University (Virginia Tech); Shultz, M.D. [Virginia Commonwealth University, Richland; Chung, Eunna [Virginia Polytechnic Institute and State University (Virginia Tech); Singh, Gurpreet [Virginia Polytechnic Institute and State University (Virginia Tech); Shu, Chunying [Virginia Polytechnic Institute and State University (Virginia Tech); Deck, Paul [Virginia Polytechnic Institute and State University (Virginia Tech); Fatouros, Panos [Virginia Commonwealth University, Richland; Henderson, Scott [Virginia Commonwealth University, Richland; Corwin, Frank [Virginia Commonwealth University, Richland; Geohegan, David B [ORNL; Rouleau, Christopher M [ORNL; More, Karren Leslie [ORNL; Rylander, Nichole M [Virginia Polytechnic Institute and State University (Virginia Tech); Rylander, Christopher [Virginia Polytechnic Institute and State University (Virginia Tech); Gibson, Harry W [Virginia Polytechnic Institute and State University (Virginia Tech); Dorn, Harry C [Virginia Polytechnic Institute and State University (Virginia Tech)

2010-07-01

278

Localized accumulation of angiotensin II and production of angiotensin-(1-7) in rat luteal cells and effects on steroidogenesis.  

PubMed

These studies aim to investigate subcellular distribution of angiotensin II (ANG II) in rat luteal cells, identify other bioactive angiotensin peptides, and investigate a role for angiotensin peptides in luteal steroidogenesis. Confocal microscopy showed ANG II distributed within the cytoplasm and nuclei of luteal cells. HPLC analysis showed peaks that eluted with the same retention times as ANG-(1-7), ANG II, and ANG III. Their relative concentrations were ANG II >or= ANG-(1-7) > ANG III, and accumulation was modulated by quinapril, an inhibitor of angiotensin-converting enzyme (ACE), Z-proprolinal (ZPP), an inhibitor of prolyl endopeptidase (PEP), and parachloromercurylsulfonic acid (PCMS), an inhibitor of sulfhydryl protease. Phenylmethylsulfonyl fluoride (PMSF), a serine protease inhibitor, did not affect peptide accumulation. Quinapril, ZPP, PCMS, and PMSF, as well as losartan and PD-123319, the angiotensin receptor type 1 (AT1) and type 2 (AT2) receptor antagonists, were used in progesterone production studies. ZPP significantly reduced luteinizing hormone (LH)-dependent progesterone production (P < 0.05). Quinapril plus ZPP had a greater inhibitory effect on LH-stimulated progesterone than either inhibitor alone, but this was not reversed by exogenous ANG II or ANG-(1-7). Both PCMS and PMSF acutely blocked LH-stimulated progesterone, and PCMS blocked LH-sensitive cAMP accumulation. Losartan inhibited progesterone production in permeabilized but not intact luteal cells and was reversed by ANG II. PD-123319 had no significant effect on luteal progesterone production in either intact or permeabilized cells. These data suggest that steroidogenesis may be modulated by angiotensin peptides that act in part through intracellular AT1 receptors. PMID:16478781

Pepperell, John R; Nemeth, Gabor; Yamada, Yuji; Naftolin, Frederick; Merino, Maricruz

2006-02-14

279

Efficacy of an injection of dinoprost tromethamine when given subcutaneously on luteal regression in lactating Holstein cows.  

PubMed

The objectives of these studies were to evaluate the efficacy of a PGF(2alpha) (PGF) analog given through different routes on causing luteal regression in lactating dairy cows. In Experiment 1, lactating Holstein cows (n=118) at random stages of lactation were blocked by parity and days in milk (DIM) and, within each block, randomly assigned to receive PGF as an intra-muscular (IM) injection in the semimembranous/semitendinous muscle (CON), subcutaneous (SC) injection in the cervical area (SCN), or SC injection in the ischio-rectal fossa (IRF). Blood was sampled at 0, 12, 24, 36, and 48 h after treatment for assessment of progesterone concentration. In Experiment 2, a total of 379 lactating Holstein cows, 46+/-7 DIM, were blocked by DIM and, within each block, randomly assigned to receive treatment similar to CON or IRF groups from Experiment 1. Blood was sampled 0 and 48 h after treatment for assessment of progesterone concentration. Cows were classified as experiencing luteal regression when progesterone concentration was <1.0 ng/mL or <40% of initial concentration (0 h=100%). In Experiment 1, there was no effect of route of PGF treatment on decline in progesterone concentration and on the proportion of cows experiencing luteal regression by 12, 24, 36, and 48 h after treatment. Similarly, in Experiment 2, route of treatment did not affect either the decline in progesterone concentration or the proportion of cows that had luteal regression by 48 h after treatment. Treatment of lactating dairy cows with 25mg of PGF given SC in the ischio-rectal fossa did not affect either the decline in progesterone concentration or the proportion of cows that experienced luteal regression by 12, 24, 36, and 48 h after PGF treatment. PMID:17126390

Chebel, Ricardo C; Santos, José E P; Rutigliano, Heloísa M; Cerri, Ronaldo L A

2006-11-28

280

Improving the in vivo persistence, distribution and function of cytotoxic T lymphocytes by inhibiting the tumor immunosuppressive microenvironment.  

PubMed

Adoptive cell transfer immunotherapy of malignant tumors has the problem of symbiosis between effector cells and tumor cells, a short in vivo residence time, and a poor killing efficiency of effector cells. Thus, releasing effector cells from the cancer immunosuppressive microenvironment and improving their effective time and functional status in vivo would seem to be ideal strategies for facilitating immunotherapy. Low-dose cyclophosphamide administration can effectively break immunotolerance by inhibiting regulatory T cells. In the present study, in order to verify whether the persistence, distribution and function of effector cells can be improved by inhibiting immunosuppressive microenvironment, low-dose cyclophosphamide was previously intraperitoneally injected into melanoma-bearing C57BL/6 mice, thereafter, CFSE-labeled cytotoxic T lymphocytes were transfused intravenously, and their effective time, distributive pattern, and killing efficiency in different groups were observed by measuring the fluorescence intensity and cell cycle of cytotoxic T lymphocytes distributed in various organs, in comparison with tumor growth. We found down-regulating Tregs in vivo can simultaneously reduce the levels of interleukin-10 and transforming growth factor-?. Migration and distribution of cytotoxic T lymphocytes in vivo was found to vary with time. Inhibition of immunotolerance can significantly improve the persistence, distribution, and function of cytotoxic T lymphocytes. Correspondingly, significantly higher secretion of perforin, granzyme B, IL-2, and IFN-? in tumor tissues with decreased tumor growth was seen in the cyclophosphamide injection group than in the control group. Our study may provide useful information on the cyclophosphamide-mediated mechanism for facilitating tumor immunotherapy by inhibiting the immunosuppressive tumor microenvironment. PMID:23659474

Xu, W; Cai, J; Li, S; Zhang, H; Han, J; Wen, M; Wen, J; Gao, F

2013-07-01

281

In vivo tracking of platelets: circulating degranulated platelets rapidly lose surface P-selectin but continue to circulate and function.  

PubMed Central

To examine the hypothesis that surface P-selectin-positive (degranulated) platelets are rapidly cleared from the circulation, we developed novel methods for tracking of platelets and measurement of platelet function in vivo. Washed platelets prepared from nonhuman primates (baboons) were labeled with PKH2 (a lipophilic fluorescent dye), thrombin-activated, washed, and reinfused into the same baboons. Three-color whole blood flow cytometry was used to simultaneously (i) identify platelets with a mAb directed against glycoprotein (GP)IIb-IIIa (integrin alpha 11b beta 3), (ii) distinguish infused platelets by their PKH2 fluorescence, and (iii) analyze platelet function with mAbs. Two hours after infusion of autologous thrombin-activated platelets (P-selectin-positive, PKH2-labeled), 95 +/- 1% (mean +/- SEM, n = 5) of the circulating PKH2-labeled platelets had become P-selectin-negative. Compared with platelets not activated with thrombin preinfusion, the recovery of these circulating PKH2-labeled, P-selectin-negative platelets was similar 24 h after infusion and only slightly less 48 h after infusion. The loss of platelet surface P-selectin was fully accounted for by a 67.1 +/- 16.7 ng/ml increase in the plasma concentration of soluble P-selectin. The circulating PKH2-labeled, P-selectin-negative platelets were still able to function in vivo, as determined by their (i) participation in platelet aggregates emerging from a bleeding time wound, (ii) binding to Dacron in an arteriovenous shunt, (iii) binding of mAb PAC1 (directed against the fibrinogen binding site on GPIIb-IIIa), and (iv) generation of procoagulant platelet-derived microparticles. In summary, (i) circulating degranulated platelets rapidly lose surface P-selectin to the plasma pool, but continue to circulate and function; and (ii) we have developed novel three-color whole blood flow cytometric methods for tracking of platelets and measurement of platelet function in vivo. Images Fig. 2 Fig. 5

Michelson, A D; Barnard, M R; Hechtman, H B; MacGregor, H; Connolly, R J; Loscalzo, J; Valeri, C R

1996-01-01

282

Common pathophysiological mechanisms involved in luteal phase deficiency and polycystic ovary syndrome. Impact on fertility.  

PubMed

Luteal phase deficiency (LPD) is a consequence of the corpus luteum (CL) inability to produce and preserve adequate levels of progesterone. This is clinically manifested by short menstrual cycles and infertility. Abnormal follicular development, defects in neo-angiogenesis or inadequate steroidogenesis in the lutein cells of the CL have been implicated in CL dysfunction and LPD. LPD and polycystic ovary syndrome (PCOS) are independent disorders sharing common pathophysiological profiles. Factors such as hyperinsulinemia, AMH excess, and defects in angiogenesis of CL are at the origin of both LPD and PCOS. In PCOS ovulatory cycles, infertility could result from dysfunctional CL. The aim of this review was to investigate common mechanisms of infertility in CL dysfunction and PCOS. PMID:22930247

Boutzios, Georgios; Karalaki, Maria; Zapanti, Evangelia

2012-08-29

283

Therapeutic nanomedicine based on dual-intelligent functionalized gold nanoparticles for cancer imaging and therapy in vivo.  

PubMed

A novel strategy to construct a therapeutic system based on functionalized AuNPs which can specifically respond to tumor microenvironment was reported. In the therapeutic system, doxorubicin was conjugated to AuNPs via thiol-Au bond by using a peptide substrate, CPLGLAGG, which can be specifically cleaved by the protease. In vivo study shows that after injection of the functionalized AuNPs to the tumor-bearing mice, the over-expressed protease of MMP-2 in tumor tissue and intracellular GSH can lead to the rapid release of the anti-tumor drug (doxorubicin) from the functionalized AuNPs to inhibit tumor growth and realize fluorescently imaging simultaneously. The functionalized AuNPs with tumor-triggered drug release property can further improve the efficacy and reduce side effects significantly. PMID:23932289

Chen, Wei-Hai; Xu, Xiao-Ding; Jia, Hui-Zhen; Lei, Qi; Luo, Guo-Feng; Cheng, Si-Xue; Zhuo, Ren-Xi; Zhang, Xian-Zheng

2013-08-09

284

Structural and Functional Dissection of the Abp1 ADFH Actin-binding Domain Reveals Versatile In Vivo Adapter FunctionsD?  

PubMed Central

Abp1 is a multidomain protein that regulates the Arp2/3 complex and links proteins involved in endocytosis to the actin cytoskeleton. All of the proposed cellular functions of Abp1 involve actin filament binding, yet the actin binding site(s) on Abp1 have not been identified, nor has the importance of actin binding for Abp1 localization and function in vivo been tested. Here, we report the crystal structure of the Saccharomyces cerevisiae Abp1 actin-binding actin depolymerizing factor homology (ADFH) domain and dissect its activities by mutagenesis. Abp1-ADFH domain and ADF/cofilin structures are similar, and they use conserved surfaces to bind actin; however, there are also key differences that help explain their differential effects on actin dynamics. Using point mutations, we demonstrate that actin binding is required for localization of Abp1 in vivo, the lethality caused by Abp1 overexpression, and the ability of Abp1 to activate Arp2/3 complex. Furthermore, we genetically uncouple ABP1 functions that overlap with SAC6, SLA1, and SLA2, showing they require distinct combinations of activities and interactions. Together, our data provide the first structural and functional view of the Abp1–actin interaction and show that Abp1 has distinct cellular roles as an adapter, linking different sets of ligands for each function.

Quintero-Monzon, Omar; Rodal, Avital A.; Strokopytov, Boris; Almo, Steven C.; Goode, Bruce L.

2005-01-01

285

Two functionally distinct domains generated by in vivo cleavage of Nup145p: a novel biogenesis pathway for nucleoporins.  

PubMed Central

Nup145p is an essential yeast nucleoporin involved in nuclear export of polyadenylated RNAs. We demonstrate here that Nup145p is cleaved in vivo to yield two functionally distinct domains: a carboxy-terminal domain (C-Nup145p) which is located at the nuclear pore complex (NPC) and assembles into the Nup84p complex, and a GLFG-containing amino-terminal domain (N-Nup145p) which is not part of this complex. Whereas the essential C-Nup145p accomplishes the functions required for efficient mRNA export and normal NPC distribution, N-Nup145p, which is homologous to the GLFG-containing nucleoporins Nup100p and Nup116p, is not necessary for cell growth. However, the N-Nup145p becomes essential in a nup188 mutant background. Strikingly, generation of a free N-domain is a prerequisite for complementation of this peculiar synthetic lethal mutant. These data suggest that N- and C-domains of Nup145p perform independent functions, and that the in vivo cleavage observed is of functional importance.

Teixeira, M T; Siniossoglou, S; Podtelejnikov, S; Benichou, J C; Mann, M; Dujon, B; Hurt, E; Fabre, E

1997-01-01

286

Application of locked nucleic acids to improve aptamer in vivo stability and targeting function  

Microsoft Academic Search

Aptamers are powerful candidates for molecular imaging applications due to a number of attractive features, including rapid blood clearance and tumor penetration. We carried out structure-activity rela- tionship (SAR) studies with the Tenascin-C binding aptamer TTA1, which is a promising candidate for application in tumor imaging with radioisotopes. The aim was to improve its in vivo stability and target binding.

Kathrin S. Schmidt; Sandra Borkowski; Jens Kurreck; Andrew W. Stephens; Rolf Bald; Maren Hecht; Matthias Friebe; Ludger Dinkelborg; Volker A. Erdmann

2004-01-01

287

Functionalized near-infrared quantum dots for in vivo tumor vasculature imaging  

Microsoft Academic Search

In this paper, we report the use of near-infrared (NIR)-emitting alloyed quantum dots (QDs) as efficient optical probes for high contrast in vivo imaging of tumors. Alloyed CdTe1 - xSex\\/CdS QDs were prepared in the non-aqueous phase using the hot colloidal synthesis approach. Water dispersion of the QDs were accomplished by their encapsulation within polyethyleneglycol (PEG)-grafted phospholipid micelles. For tumor-specific

Rui Hu; Ken-Tye Yong; Indrajit Roy; Hong Ding; Wing-Cheung Law; Hongxing Cai; Xihe Zhang; Lisa A. Vathy; Earl J. Bergey; Paras N. Prasad

2010-01-01

288

Arginyltransferase is an ATP-Independent Self-Regulating Enzyme that Forms Distinct Functional Complexes In Vivo  

PubMed Central

Summary Posttranslational arginylation mediated by arginyltransferase (ATE1) plays an important role in cardiovascular development, cell motility and regulation of cytoskeleton and metabolic enzymes. This protein modification was discovered decades ago, however, the arginylation reaction and the functioning of ATE1 remained poorly understood due to the lack of good biochemical models. Here we report the development of an in vitro arginylation system, in which ATE1 function and molecular requirements can be tested using purified recombinant ATE1 isoforms supplemented with a controlled number of components. Our results show that arginylation reaction is a self-sufficient, ATP-independent process that can affect different sites in a polypeptide, and that arginyltransferases form different molecular complexes in vivo, associate with components of the translation machinery, and have distinct, partially overlapping subsets of substrates, suggesting that these enzymes play different physiological functions.

Wang, Junling; Han, Xuemei; Saha, Sougata; Xu, Tao; Rai, Reena; Zhang, Fangliang; Wolf, Yuri. I.; Wolfson, Alexey; Yates, John R.; Kashina, Anna

2010-01-01

289

A randomized comparison of side effects and patient convenience between Cyclogest ® suppositories and Endometrin ® tablets used for luteal phase support in IVF treatment  

Microsoft Academic Search

ObjectiveThis study compared side effects and patient convenience of vaginal progesterone suppositories (Cyclogest®) and vaginal progesterone tablets (Endometrin®) used for luteal phase support in in vitro fertilization\\/embryo transfer (IVF\\/ET) cycles using pituitary downregulation.

Ernest Hung Yu Ng; Carina Chi Wai Chan; Oi Shan Tang; Pak Chung Ho

2007-01-01

290

Luteal function and blood flow during intravenous infusion of prostaglandin F2? in heifers  

Microsoft Academic Search

The effect of prostaglandin F2? (PGF) infusion for 3 h into the jugular vein on progesterone concentrations was studied in 24 Holstein heifers. Plasma concentrations of PGF were assessed by assay of 13,14-dihydro-15-keto-PGF (PGFM). The 3 h of PGF infusion were used to approximate the duration of the major concentrations of PGFM in a natural pulse. During infusion of 5,

O. J. Ginther; R. R. Araujo; B. L. Rodrigues; M. A. Beg

291

Association Between Energy Balance and Luteal Function in Lactating Dairy Cows  

Microsoft Academic Search

ABSTRACT Our,objective,was,to determine,the relationship,between,energy,balance,and secretion,of progesterone,in,lactating dairy,cows.,Eight primiparous,and,24 muhiparous,lactating Holstein cows,were studied,from,parturition,to 100 d post- partum,or,conception.,Cows,calved normally,and,remained,healthy,through- out,the,study. All cows,were,fed,ad libitum,a total mixed,diet formulated,to satisfy requirements,for maintenance,and lactation. Intake of feed and,production of,milk,per,cow,were,measured,twice daily. Body,weight,was,determined weekly.,Daily energy,balance,was,de- termined,by,subtracting,energy,required for,maintenance,and,lactation,from intake,of,energy.,Concentrations,of progesterone,were,determined,in milk sampled,every,3rd d. For at,least 4 successive d postpartum, 81% of cows were,in negative,energy,balance. Varia- tion,in,energy,balance,was,explained largely by intake,of

A. Villa-Godoy; T. L. Hughes; R. S. Emery; L. T. Chapin; R. L. Fogwell

1988-01-01

292

Noninvasive Assessment of Gene Transfer and Expression by In Vivo Functional and Morphologic Imaging in a Rabbit Tumor Model  

PubMed Central

Purpose To evaluate the importance of morphology in quantifying expression after in vivo gene transfer and to compare gene expression after intra-arterial (IA) and intra-tumoral (IT) delivery of adenovirus expressing a SSTR2-based reporter gene in a large animal tumor model. Materials and Methods Tumor directed IA or IT delivery of adenovirus containing a human somatostatin receptor type 2A (Ad-CMV-HA-SSTR2A) gene chimera or control adenovirus (Ad-CMV-GFP) was performed in VX2 tumors growing in both rabbit thighs. Three days later, 111In-octreotide was administered intravenously after CT imaging using a clinical scanner. 111In-octreotide uptake in tumors was evaluated the following day using a clinical gamma-camera. Gene expression was normalized to tumor weight with and without necrosis. This procedure was repeated on nine additional rabbits to investigate longitudinal gene expression both 5 days and 2 weeks after adenovirus delivery. CT images were used to evaluate tumor morphology and excised tissue samples were analyzed to determine 111In-octreotide biodistribution ex vivo. Results VX2 tumors infected with Ad-CMV-HA-SSTR2 had greater 111In-octreotide uptake than with control virus (P<0.05). Intra-arterial and intra-tumoral routes resulted in similar levels of gene expression. Longitudinally, expression appeared to wane at 2 weeks versus 5 days after delivery. Areas of necrosis did not demonstrate significant uptake ex vivo. Morphology identified areas of necrosis on contrast enhanced CT and upon excluding necrosis, in vivo biodistribution analysis resulted in greater percent injected dose per gram (P<0.01) and corresponded better with ex vivo biodistribution(r?=?0.72, P<0.01, Coefficient of the x-variable?=?.72) at 2 weeks than without excluding necrosis (P<0.01). Conclusion Tumor specificity and high transgene expression can be achieved in tumors via both tumor directed intra-arterial and intra-tumoral delivery in a large animal tumor model. Using clinical machines, morphologic imaging contributes to functional imaging for quantifying SSTR2-based reporter expression in vivo.

Ravoori, Murali K.; Han, Lin; Singh, Sheela P.; Dixon, Katherine; Duggal, Jyoti; Liu, Ping; Uthamanthil, Rajesh; Gupta, Sanjay; Wright, Kenneth C.; Kundra, Vikas

2013-01-01

293

The neurexin ligands, neuroligins and leucine-rich repeat transmembrane proteins, perform convergent and divergent synaptic functions in vivo  

PubMed Central

Synaptic cell adhesion molecules, including the neurexin ligands, neuroligins (NLs) and leucine-rich repeat transmembrane proteins (LRRTMs), are thought to organize synapse assembly and specify synapse function. To test the synaptic role of these molecules in vivo, we performed lentivirally mediated knockdown of NL3, LRRTM1, and LRRTM2 in CA1 pyramidal cells of WT and NL1 KO mice at postnatal day (P)0 (when synapses are forming) and P21 (when synapses are largely mature). P0 knockdown of NL3 in WT or NL1 KO neurons did not affect excitatory synaptic transmission, whereas P0 knockdown of LRRTM1 and LRRTM2 selectively reduced AMPA receptor-mediated synaptic currents. P0 triple knockdown of NL3 and both LRRTMs in NL1 KO mice yielded greater reductions in AMPA and NMDA receptor-mediated currents, suggesting functional redundancy between NLs and LRRTMs during early synapse development. In contrast, P21 knockdown of LRRTMs did not alter excitatory transmission, whereas NL manipulations supported a role for NL1 in maintaining NMDA receptor-mediated transmission. These results show that neurexin ligands in vivo form a dynamic synaptic cell adhesion network, with compensation between NLs and LRRTMs during early synapse development and functional divergence upon synapse maturation.

Soler-Llavina, Gilberto J.; Fuccillo, Marc V.; Ko, Jaewon; Sudhof, Thomas C.; Malenka, Robert C.

2011-01-01

294

Measuring stem cell frequency in epidermis: A quantitative in vivo functional assay for long-term repopulating cells  

NASA Astrophysics Data System (ADS)

Epidermal stem cells play a central role in tissue homeostasis, wound repair, tumor initiation, and gene therapy. A major impediment to the purification and molecular characterization of epidermal stem cells is the lack of a quantitative assay for cells capable of long-term repopulation in vivo, such as exists for hematopoietic cells. The tremendous strides made in the characterization and purification of hematopoietic stem cells have been critically dependent on the availability of competitive transplantation assays, because these assays permit the accurate quantitation of long-term repopulating cells in vivo. We have developed an analogous functional assay for epidermal stem cells, and have measured the frequency of functional epidermal stem cells in interfollicular epidermis. These studies indicate that cells capable of long-term reconstitution of a squamous epithelium reside in the interfollicular epidermis. We find that the frequency of these long-term repopulating cells is 1 in 35,000 total epidermal cells, or in the order of 1 in 104 basal epidermal cells, similar to that of hematopoietic stem cells in the bone marrow, and much lower than previously estimated in epidermis. Furthermore, these studies establish a novel functional assay that can be used to validate immunophenotypic markers and enrichment strategies for epidermal stem cells, and to quantify epidermal stem cells in various keratinocyte populations. Thus further studies using this type of assay for epidermis should aid in the progress of cutaneous stem cell-targeted gene therapy, and in more basic studies of epidermal stem cell regulation and differentiation.

Schneider, T. E.; Barland, C.; Alex, A. M.; Mancianti, M. L.; Lu, Y.; Cleaver, J. E.; Lawrence, H. J.; Ghadially, R.

2003-09-01

295

Nucleotide binding by Lhs1p is essential for its nucleotide exchange activity and for function in vivo.  

PubMed

Protein translocation and folding in the endoplasmic reticulum of Saccharomyces cerevisiae involves two distinct Hsp70 chaperones, Lhs1p and Kar2p. Both proteins have the characteristic domain structure of the Hsp70 family consisting of a conserved N-terminal nucleotide binding domain and a C-terminal substrate binding domain. Kar2p is a canonical Hsp70 whose substrate binding activity is regulated by cochaperones that promote either ATP hydrolysis or nucleotide exchange. Lhs1p is a member of the Grp170/Lhs1p subfamily of Hsp70s and was previously shown to function as a nucleotide exchange factor (NEF) for Kar2p. Here we show that in addition to this NEF activity, Lhs1p can function as a holdase that prevents protein aggregation in vitro. Analysis of the nucleotide requirement of these functions demonstrates that nucleotide binding to Lhs1p stimulates the interaction with Kar2p and is essential for NEF activity. In contrast, Lhs1p holdase activity is nucleotide-independent and unaffected by mutations that interfere with ATP binding and NEF activity. In vivo, these mutants show severe protein translocation defects and are unable to support growth despite the presence of a second Kar2p-specific NEF, Sil1p. Thus, Lhs1p-dependent nucleotide exchange activity is vital for ER protein biogenesis in vivo. PMID:19759005

de Keyzer, Jeanine; Steel, Gregor J; Hale, Sarah J; Humphries, Daniel; Stirling, Colin J

2009-09-15

296

Cellular and functional characterization of buffalo (Bubalus bubalis) corpus luteum during the estrous cycle and pregnancy.  

PubMed

In the present paper, cellular composition of buffalo corpus luteum (CL) with its functional characterization based on 3?-HSD and progesterone secretory ability at different stages of estrous cycle and pregnancy was studied. Buffalo uteri along with ovaries bearing CL were collected from the local slaughter house. These were classified into different stages of estrous cycle (Stage I, II, III and IV) and pregnancy (Stage I, II and III) based on morphological appearance of CL, surface follicles on the ovary and crown rump length of conceptus. Luteal cell population, progesterone content and steroidogenic properties were studied by dispersion of luteal cells using collagenase type I enzyme, RIA and 3?-HSD activity, respectively. Large luteal cells (LLC) appeared as polyhedral or spherical in shape with a centrally placed large round nucleus and an abundance of cytoplasmic lipid droplets. However, small luteal cells (SLC) appeared to be spindle shaped with an eccentrically placed irregular nucleus and there was paucity of cytoplasmic lipid droplets. The size of SLC (range 12-23?m) and LLC (range 25-55?m) increased (P<0.01) with the advancement of stage of estrous cycle and pregnancy. The mean progesterone concentration per gram and per CL increased (P<0.01) from Stage I to III of estrous cycle with maximum concentration at Stage III of estrous cycle and pregnancy. The progesterone concentration decreased at Stage IV (day 17-20) of estrous cycle coinciding with CL regression. Total luteal cell number (LLC and SLC) also increased (P<0.01) from Stage I to III of estrous cycle and decreased (P<0.05), thereafter, at Stage IV indicating degeneration of luteal cells and regression of the CL. Total luteal cell population during pregnancy also increased (P<0.01) from Stage I to II and thereafter decreased (P>0.05) indicating cessation of mitosis. Increased (P<0.05) large luteal cell numbers from Stage I to III of estrous cycle and pregnancy coincided with the increased progesterone secretion and 3?-HSD activity of CL. Thus, proportionate increases of large compared with small luteal cells were primarily responsible for increased progesterone secretion during the advanced stages of the estrous cycle and pregnancy. Total luteal cells and progesterone content per CL during the mid-luteal stage in buffalo as observed in the present study seem to be less than with cattle suggesting inherent luteal deficiency. PMID:23896394

Baithalu, Rubina Kumari; Singh, S K; Gupta, Chhavi; Raja, Anuj K; Saxena, Abhishake; Kumar, Yogendra; Singh, R; Agarwal, S K

2013-06-28

297

Fxr1 knockout mice show a striated muscle phenotype: implications for Fxr1p function in vivo  

Microsoft Academic Search

FXR1 is one of the two known homologues of FMR1. FXR1 shares a high degree\\u000a of sequence homology with FMR1 and also encodes two KH domains and an RGG\\u000a domain, conferring RNA-binding capabilities. In comparison with FMRP, very\\u000a little is known about the function of FXR1P in vivo. Mouse knockout (KO)\\u000a models exist for both Fmr1 and Fxr2. To study

Edwin J. Mientjes; Rob Willemsen; Laura L. Kirkpatrick; Ingeborg M. Nieuwenhuizen; Marianne Hoogeveen-Westerveld; Marcel Verweij; Surya Reis; Barbara Bardoni; Andre T. Hoogeveen; Ben A. Oostra; David L. Nelson

2004-01-01

298

Coexpression of integrin-associated protein (IAP\\/CD47) and its ligand thrombospondin-1 on human granulosa and large luteal cells  

Microsoft Academic Search

In the present study, we have raised a monoclonal antibody (mAb) designated OG-4 against human granulosa cells (GC). By immunohistochemistry, the expression of OG-4 antigen was observed on human GC and large luteal cells, but not on thecal and small luteal cells. A complementary DNA (cDNA) clone encoding OG-4 antigen was screened and isolated by a panning method using OG-4

Toshihiro Higuchi; Hiroshi Fujiwara; Shigetoshi Yamada; Keiji Tatsumi; Nobuhiko Kataoka; Katsuhiko Itoh; Michiyuki Maeda; Jun Fujita; Shingo Fujii

1999-01-01

299

Directed dimerization: an in vivo expression system for functional studies of type II phytochromes.  

PubMed

Type II phytochromes (phy) in Arabidopsis form homodimers and heterodimers, resulting in a diverse collection of light-stable red/far-red (R/FR) sensing photoreceptors. We describe an in vivo protein engineering system and its use in characterizing the activities of these molecules. Using a phyB null mutant background, singly and doubly transgenic plants were generated that express fusion proteins containing the phyB-phyE N-terminal photosensory regions (NB-NE PSRs), a nuclear localization sequence, and small yeast protein domains that mediate either homodimerization or heterodimerization. Activity of NB/NB homodimers but not monomeric NB subunits in control of seedling and adult plant responses to R light is demonstrated. Heterodimers of the NB sequence with the chromophoreless NB(C357S) sequence, which mimic phyB Pfr/Pr photo-heterodimers, mediate R sensitivity in leaves and petioles but not hypocotyls. Homodimerization of the NC, ND and NE sequences and directed heterodimerization of these photosensory regions with the NB region reveal form-specific R-induced activities for different type II phy dimers. The experimental approach developed here of directed assembly of defined protein dimer combinations in vivo may be applicable to other systems. PMID:23738620

Liu, Peng; Sharrock, Robert A

2013-08-03

300

Functional in vivo imaging of cysteine cathepsin activity in murine model of inflammation.  

PubMed

Near-infrared fluorophore (NIRF)-labeled imaging probes are becoming increasingly important in bio-molecular imaging applications, that is, in animal models for tumor imaging or inflammation studies. In this study we showed that the previously introduced chemical concept of 'Reverse Design' represents an efficient strategy for the generation of selective probes for cysteine proteases from chemically optimized protease inhibitors for investigations in proteomic lysates as well as for in vivo molecular imaging studies. The newly developed activity-based probe AW-091 was demonstrated to be highly selective for cathepsin S in vitro and proved useful in monitoring cysteine cathepsin activity in vivo, that is, in zymosan-induced mouse model of inflammation. AW-091 showed higher signal-to-background ratios at earlier time points than the commercially available polymer-based ProSense680 (VisEn Medical) and thus represents an efficient new tool for studying early proteolytic processes leading to various diseases, including inflammation, cancer, and rheumatoid arthritis. In addition, the fluorescent signal originating from the cleaved AW-091 was shown to be reduced by the administration of an anti-inflammatory drug, dexamethasone and by the cathepsin inhibitor E-64, providing a valuable system for the evaluation of small-molecule inhibitors of cathepsins. PMID:21130662

Cagli?, Dejan; Globisch, Anja; Kindermann, Maik; Lim, Ngee-Han; Jeske, Volker; Juretschke, Hans-Paul; Bartnik, Eckart; Weithmann, K Ulrich; Nagase, Hideaki; Turk, Boris; Wendt, K Ulrich

2010-10-19

301

Oral contraceptive effects on food choice during the follicular and luteal phases of the menstrual cycle. A laboratory based study.  

PubMed

Fifty-five women were recruited and assigned to a control group or an oral contraceptive (OC) use group. For the control groups menstrual cycle phase was determined using a menstrual calendar and only participants with regular cycles were recruited. Testing was carried out during a single day of the luteal and follicular phases, where participants were asked to consume and rate sweet and savoury snacks. Participants in the OC group were tested on the equivalent days of their pill calendar. In both groups, the luteal phase induced a greater caloric intake of sweet foods without altering hedonic ratings. No significant interactions between either phase or flavour with OC use on food intake or hedonic food ratings were found. At least for snack items, OC do not seem to alter the caloric intake fluctuations that occur during a normal menstrual cycle. PMID:20561549

Tucci, S A; Murphy, L E; Boyland, E J; Dye, L; Halford, J C G

2010-06-16

302

Cocaine Pharmacokinetics in Men and in Women During the Follicular and Luteal Phases of the Menstrual Cycle  

Microsoft Academic Search

Preclinical and clinical studies suggest that females may be less vulnerable to cocaine's toxic effects than males. The pharmacokinetics of intravenous cocaine (0.2 and 0.4 mg\\/kg) were measured in 12 men and 22 women with a history of cocaine abuse, matched with respect to age and body mass index (BMI). Women were studied during the follicular and the luteal phases

Jack H Mendelson; Nancy K Mello; Michelle B Sholar; Arthur J Siegel; Marc J Kaufman; Jonathan M Levin; Perry F Renshaw; Bruce M Cohen

1999-01-01

303

Endometrial integrin expression in the early luteal phase in natural and stimulated cycles for in vitro fertilization  

Microsoft Academic Search

Objective: To investigate the effect of ovarian stimulation on integrin expression in the early luteal phase. Study design: Seven endometrial biopsies were taken 2 days after the oocyte retrieval from stimulated cycles for IVF and 23 from natural cycles, 2 days after ovulation. Result: Endometrium was in-phase in 22\\/23 and 7\\/7 biopsies from the natural and stimulated cycles, respectively. Integrins

Asimina Tavaniotou; Claire Bourgain; Carola Albano; Peter Platteau; Johan Smitz; Paul Devroey

2003-01-01

304

Differential expression and regulation of prostaglandin E synthases in the mouse ovary during sexual maturation and luteal development  

Microsoft Academic Search

Prostaglandin (PGE) 2 is the most common prostanoid and plays an important role in female reproduction. The aim of this study was to examine the expression and regulation of microsomal (m) PGE synthase (PGES)-1 and cytosolic (c) PGES in the mouse ovary during sexual maturation, gonadotropin treatment and luteal develop- ment by in situ hybridization and immunohistochemistry. Both mPGES-1 mRNA

Tong Sun; Wen-Bo Deng; Hong-Lu Diao; Hua Ni; Yu-Yan Bai; Xing-Hong Ma; Li-Bin Xu; Zeng-Ming Yang

2006-01-01

305

Plasma Progesterone Levels and Luteal Activity during Gestation and Prolonged Oviductal Egg Retention in a Tropical Lizard, Calotes versicolor  

Microsoft Academic Search

Plasma progesterone (P) levels and luteal and adrenal activities were studied during normal gestation and unusual prolonged period of oviductal egg retention in a polyautochronic, multiclutched lizard, Calotes versicolor. The normal gestation period (?15 days) was categorized into four stages: stage I—a few hours following ovulation, stage II—eggs with shell and embryo at primitive streak, stage III—embryonic stages 16–20, and

B. A. Shanbhag; R. S. Radder; S. K. Saidapur

2001-01-01

306

Different processing of LH/hCG receptors in cultured rat luteal cells and murine Leydig tumor cells (MLTC-1)  

SciTech Connect

The metabolic fate of LH/hCG receptors after exposure to human chorionic gonadotropin (hCG) was examined in cultured rat luteal cells and murine Leydig tumor cells (MLTC-1). Kinetic studies performed after pulse-labelling of the cells with (/sup 125/I)hCG indicated that the bound hormone was lost much more rapidly from the tumor cells than from the luteal cells. The tumor cells were also found to internalize and degrade the hormone more effectively than the luteal cells. Chemical cross-linking and analyses by SDS-PAGE of this material revealed that both cell types also released, in addition to intact hCG, two previously characterized receptor fragment-(/sup 125/I)hCG complexes (M/sub r/ 96,000 and 74,000) into the medium, although their amount was negligible in MLTC-1 cells. Possibly due to rapid discharge of the ligand from its receptor, no similar complexes could be detected inside the MLTC-1 cells, suggesting that they were released directly from the cell surface. However, the M/sub r/ 74,000 complex was observed inside MLTC-1 cells if chloroquine, a lysosomotropic agent, was present during the incubations. This suggests that the internalized receptor also becomes degraded, at least when complexed to hCG. The results thus provide evidence that there exist two different mechanisms for proteolytic processing of LH/hCG receptors in these target cells. In tumor cells, the degradation seems to occur almost exclusively intracellularly, whereas in luteal cells a substantial portion of the receptors is also degraded at the cell surface.

Kellokumpu, S.

1987-02-01

307

Tissue kallikrein and bradykinin B2 receptor in human uterus in luteal phase and in early and late gestation  

Microsoft Academic Search

This study was addressed to evaluate the temporospatial pattern of key components of the kallikreinkinin system in human uterus\\u000a in luteal phase (n=7), early pregnancy (isolated spontaneous abortions, n = 11; ectopic pregnancies, n=9), idiopathic preterm deliveries (n=5), and term gestations (n=12). Tissue kallikrein mRNA and protein and the type 2 bradykinin receptor (B2R) protein were expressed in luminal and

Gloria Valdés; Alfredo M. Germain; Jenny Corthorn; Cecilia Chacón; Carlos D. Figueroa; Werner Müller-Esterl

2001-01-01

308

PEG-Mediated Synthesis of Highly Dispersive Multifunctional Superparamagnetic Nanoparticles: Their Physicochemical Properties and Function In Vivo  

PubMed Central

Multifunctional superparamagnetic nanoparticles have been developed for a wide range of applications in nanomedicine, such as serving as tumor targeted drug carriers and molecular imaging agents. To function in vivo, the development of these novel materials must overcome several challenging requirements including biocompatibility, stability in physiological solutions, non-toxicity and the ability to traverse biological barriers. Here we report a PEG-mediated synthesis process to produce well-dispersed, ultrafine, and highly stable iron oxide nanoparticles for in vivo applications. Utilizing a biocompatible PEG coating bearing amine functional groups, the produced nanoparticles serve as an effective platform with the ability to incorporate a variety of targeting, therapeutic or imaging ligands. In this study, we demonstrated tumor-specific accumulation of these nanoparticles through both magnetic resonance and optical imaging after conjugation with chlorotoxin, a peptide with high affinity toward tumors of the neuroectodermal origin, and Cy5.5, a near-infrared fluorescent dye. Furthermore, we performed preliminary biodistribution and toxicity assessments of these nanoparticles in wild-type mice through histological analysis of clearance organs and hematology assay, and the results demonstrated the relative biocompatibility of these nanoparticles.

Sun, Conroy; Du, Kim; Fang, Chen; Bhattarai, Narayan; Veiseh, Omid; Kivit, Forrest; Stephen, Zachary; Lee, Donghoon; Ellenbogen, Richard G.; Ratner, Buddy; Zhang, Miqin

2010-01-01

309

In vivo functional role of the Drosophila hyperkinetic beta subunit in gating and inactivation of Shaker K+ channels.  

PubMed Central

The physiological roles of the beta, or auxiliary, subunits of voltage-gated ion channels, including Na+, Ca2+, and K+ channels, have not been demonstrated directly in vivo. Drosophila Hyperkinetic (Hk) mutations alter a gene encoding a homolog of the mammalian K+ channel beta subunit, providing a unique opportunity to delineate the in vivo function of auxiliary subunits in K+ channels. We found that the Hk beta subunit modulates a wide range of the Shaker (Sh) K+ current properties, including its amplitude, activation and inactivation, temperature dependence, and drug sensitivity. Characterizations of the existing mutants in identified muscle cells enabled an analysis of potential mechanisms of subunit interactions and their functional consequences. The results are consistent with the idea that via hydrophobic interaction, Hk beta subunits modulate Sh channel conformation in the cytoplasmic pore region. The modulatory effects of the Hk beta subunit appeared to be specific to the Sh alpha subunit because other voltage- and Ca(2+)-activated K+ currents were not affected by Hk mutations. The mutant effects were especially pronounced near the voltage threshold of IA activation, which can disrupt the maintenance of the quiescent state and lead to the striking neuromuscular and behavioral hyperexcitability previously reported.

Wang, J W; Wu, C F

1996-01-01

310

Constant TCR triggering suggests that the TCR expressed on intestinal intraepithelial ?? T cells is functional in vivo.  

PubMed

Intestinal intraepithelial lymphocytes carrying the ?? TCR (?? iIEL) are involved in the maintenance of epithelial integrity. ?? iIEL have an activated phenotype, characterized by CD69 expression and increased cell size compared with systemic T lymphocytes. As an additional activation marker, the majority of ?? iIEL express the CD8?? homodimer. However, our knowledge about cognate ligands for most ?? TCR remains fragmentary and recent advances show that ?? T cells including iIEL may be directly activated by cytokines or through NK-receptors, TLR and other pattern recognition receptors. We therefore asked whether the TCR of ?? iIEL was functional beyond its role during thymic selection. Using TcrdH2BeGFP (Tcrd, T-cell receptor ? locus; H2B, histone 2B) reporter mice to identify ?? T cells, we measured their intracellular free calcium concentration in response to TCR-crosslinking. In contrast to systemic ?? T cells, CD8??(+) ?? iIEL showed high basal calcium levels and were refractory to TCR-dependent calcium-flux induction; however, they readily produced CC chemokine ligand 4 (CCL4) and IFN-? upon TCR triggering in vitro. Notably, in vivo blocking of the ?? TCR with specific mAb led to a decrease of basal calcium levels in CD8??(+) ?? iIEL. This suggests that the ?? TCR of CD8??(+) ?? iIEL is constantly being triggered and therefore functional in vivo. PMID:21108461

Malinarich, Frano H; Grabski, Elena; Worbs, Tim; Chennupati, Vijaykumar; Haas, Jan D; Schmitz, Susanne; Candia, Enzo; Quera, Rodrigo; Malissen, Bernard; Förster, Reinhold; Hermoso, Marcela; Prinz, Immo

2010-11-11

311

Regulation of memory CD4 T-cell pool size and function by natural killer T cells in vivo  

PubMed Central

To develop more effective vaccines and strategies to regulate chronic inflammatory diseases, it is important to understand the mechanisms of immunological memory. Factors regulating memory CD4+ T helper (Th)-cell pool size and function remain unclear, however. We show that activation of type I invariant natural killer T (iNKT) cells with glycolipid ligands and activation of type II natural killer T (NKT) cells with the endogenous ligand sulfatide induced dramatic proliferation and expansion of memory, but not naïve, CD4 T cells. NKT cell-induced proliferation of memory Th1 and Th2 cells was dependent largely on the production of IL-2, with Th2-cell proliferation also affected by loss of IL-4. Type II NKT cells were also required for efficient maintenance of memory CD4 T cells in vivo. Activation of iNKT cells resulted in up-regulation of IFN-? expression by memory Th2 cells. These IFN-?–producing memory Th2 cells showed a decreased capability to induce Th2 cytokines and eosinophilic airway inflammation. Thus, activated NKT cells directly regulate memory CD4 T-cell pool size and function via the production of cytokines in vivo.

Iwamura, Chiaki; Shinoda, Kenta; Endo, Yusuke; Watanabe, Yukiko; Tumes, Damon John; Motohashi, Shinichiro; Kawahara, Kazuyoshi; Kinjo, Yuki; Nakayama, Toshinori

2012-01-01

312

PEG-mediated synthesis of highly dispersive multifunctional superparamagnetic nanoparticles: their physicochemical properties and function in vivo.  

PubMed

Multifunctional superparamagnetic nanoparticles have been developed for a wide range of applications in nanomedicine, such as serving as tumor-targeted drug carriers and molecular imaging agents. To function in vivo, the development of these novel materials must overcome several challenging requirements including biocompatibility, stability in physiological solutions, nontoxicity, and the ability to traverse biological barriers. Here we report a PEG-mediated synthesis process to produce well-dispersed, ultrafine, and highly stable iron oxide nanoparticles for in vivo applications. Utilizing a biocompatible PEG coating bearing amine functional groups, the produced nanoparticles serve as an effective platform with the ability to incorporate a variety of targeting, therapeutic, or imaging ligands. In this study, we demonstrated tumor-specific accumulation of these nanoparticles through both magnetic resonance and optical imaging after conjugation with chlorotoxin, a peptide with high affinity toward tumors of the neuroectodermal origin, and Cy5.5, a near-infrared fluorescent dye. Furthermore, we performed preliminary biodistribution and toxicity assessments of these nanoparticles in wild-type mice through histological analysis of clearance organs and hematology assay, and the results demonstrated the relative biocompatibility of these nanoparticles. PMID:20232826

Sun, Conroy; Du, Kim; Fang, Chen; Bhattarai, Narayan; Veiseh, Omid; Kievit, Forrest; Stephen, Zachary; Lee, Donghoon; Ellenbogen, Richard G; Ratner, Buddy; Zhang, Miqin

2010-04-27

313

Impact of nonnatural amino acid mutagenesis on the in vivo function and binding modes of a transcriptional activator.  

PubMed

Protein-protein interactions play an essential role in cellular function, and methods to discover and characterize them in their native context are of paramount importance for gaining a deeper understanding of biological networks. In this study, an enhanced nonsense suppression system was utilized to incorporate the nonnatural amino acid p-benzoyl-L-phenylalanine (pBpa) throughout the transcriptional activation domain of the prototypical eukaryotic transcriptional activator Gal4 in vivo (S. cerevisiae). Functional studies of the pBpa-containing Gal4 mutants suggest that this essential binding interface of Gal4 is minimally impacted by these substitutions, with both transcriptional activity and sensitivity to growth conditions maintained. Further supporting this are in vivo cross-linking studies, including the detection of a key binding partner of Gal4, the inhibitor protein Gal80. Cross-linking with a range of pBpa-containing mutants revealed a Gal4 x Gal80 binding interface that extends beyond that previously predicted by conventional strategies. Thus, this approach can be broadened to the discovery of novel binding partners of transcription factors, information that will be critical for the development of therapeutically useful small molecule modulators of these protein-protein interactions. PMID:19764747

Majmudar, Chinmay Y; Lee, Lori W; Lancia, Jody K; Nwokoye, Adaora; Wang, Qian; Wands, Amberlyn M; Wang, Lei; Mapp, Anna K

2009-10-14

314

Delta-catenin is required for the maintenance of neural structure and function in mature cortex in vivo.  

PubMed

Delta-catenin is a brain-specific member of the adherens junction complex that localizes to the postsynaptic and dendritic compartments. This protein is likely critical for normal cognitive function; its hemizygous loss is linked to the severe mental retardation syndrome Cri-du-Chat and it directly interacts with presenilin-1 (PS1), the protein most frequently mutated in familial Alzheimer's disease. Here we examine dendritic structure and cortical function in vivo in mice lacking delta-catenin. We find that in cerebral cortex of 5-week-old mice, dendritic complexity, spine density, and cortical responsiveness are similar between mutant and littermate controls; thereafter, mutant mice experience progressive dendritic retraction, a reduction in spine density and stability, and concomitant reductions in cortical responsiveness. Our results indicate that delta-catenin regulates the maintenance of dendrites and dendritic spines in mature cortex but does not appear to be necessary for the initial establishment of these structures during development. PMID:19914181

Matter, Cheryl; Pribadi, Mochtar; Liu, Xin; Trachtenberg, Joshua T

2009-11-12

315

In vivo Function and Membrane Binding Properties are Correlated for Escherichia coli LamB Signal Peptides  

NASA Astrophysics Data System (ADS)

Wild-type and pseudorevertant signal peptides of the lamB gene product of Escherichia coli interact with lipid systems whereas a nonfunctional deletion mutant signal peptide does not. This conclusion is based on (i) interaction of synthetic signal peptides with a lipid monolayer-water surface, (ii) conformational changes induced by presence of lipid vesicles in an aqueous solution of signal peptide, and (iii) capacities of the peptides to promote vesicle aggregation. Analysis of the signal sequences and previous conformational studies suggest that these lipid interaction properties may be attributable to the tendency of the functional signal peptides to adopt ? -helical conformations. Although the possibility of direct interaction between the signal peptide and membrane lipids during protein secretion is controversial, the results suggest that conformationally related amphiphilicity and consequent membrane affinity of signal sequences are important for function in vivo.

Briggs, Martha S.; Gierasch, Lila M.; Zlotnick, Adam; Lear, James D.; Degrado, William F.

1985-05-01

316

In Vivo Determination of Vitamin D Function Using Transgenic Mice Carrying a Human Osteocalcin Luciferase Reporter Gene  

PubMed Central

Vitamin D is an essential factor for ossification, and its deficiency causes rickets. Osteocalcin, which is a noncollagenous protein found in bone matrix and involved in mineralization and calcium ion homeostasis, is one of the major bone morphogenetic markers and is used in the evaluation of osteoblast maturation and osteogenic activation. We established transgenic mouse line expressing luciferase under the control of a 10-kb osteocalcin enhancer/promoter sequence. Using these transgenic mice, we evaluated the active forms of vitamins D2 and D3 for their bone morphogenetic function by in vivo bioluminescence. As the result, strong activity for ossification was observed with 1?,25-hydroxyvitamin D3. Our mouse system can offer a feasible detection method for assessment of osteogenic activity in the development of functional foods and medicines by noninvasive screening.

Nakanishi, Tomoko; Saito, Rumiko; Taniguchi, Makoto; Oda, Haruka; Soma, Atsumi; Yasunaga, Mayu; Yamane, Mariko; Sato, Kenzo

2013-01-01

317

In vivo biological responses to silk proteins functionalized with bone sialoprotein.  

PubMed

Recombinant 6mer?+?BSP protein, combining six repeats of the consensus sequence for Nephila clavipes dragline (6mer) and bone sialoprotein sequence (BSP), shows good support for cell viability and induces the nucleation of hydroxyapatite and tricalcium phosphate during osteoblast in vitro culture. The present study is conducted to characterize this bioengineered protein-based biomaterial further for in vivo behavior related to biocompatibility. 6mer?+?BSP protein films are implanted in subcutaneous pouches in the back of mice and responses are evaluated by flow cytometry and histology. The results show no major differences between the inflammatory responses induced by 6mer?+?BSP films and the responses observed for the controls. Thus, this new chimeric protein could represent an alternative for bone regeneration applications. PMID:23359587

Gomes, Sílvia; Gallego-Llamas, Jabier; Leonor, Isabel B; Mano, João F; Reis, Rui L; Kaplan, David L

2013-01-28

318

In vivo functional photoacoustic tomography of traumatic brain injury in rats  

NASA Astrophysics Data System (ADS)

In this study, we demonstrate the potential of photoacoustic tomography for the study of traumatic brain injury (TBI) in rats in vivo. Based on spectroscopic photoacoustic tomography that can detect the absorption rates of oxy- and deoxy-hemoglobins, the blood oxygen saturation and total blood volume in TBI rat brains were visualized. Reproducible cerebral trauma was induced using a fluid percussion TBI device. The time courses of the hemodynamic response following the trauma initiation were imaged with multi-wavelength photoacoustic tomography with bandwidth-limited spatial resolution through the intact skin and skull. In the pilot set of experiments, trauma induced hematomas and blood oxygen saturation level changes were detected, a finding consistent with the known physiological responses to TBI. This new imaging method will be useful for future studies on TBI-related metabolic activities and the effects of therapeutic agents.

Oh, Jung-Taek; Song, Kwang-Hyun; Li, Meng-Lin; Stoica, George; Wang, Lihong V.

2006-03-01

319

Lipopolysaccharide enhances Fc?R-dependent functions in vivo through CD11b/CD18 up-regulation  

PubMed Central

Fc receptors for immunoglobulin G (IgG) (Fc?R) mediate several defence mechanisms in the course of inflammatory and infectious diseases. In Gram-negative infections, cellular wall lipopolysaccharides (LPS) modulate different immune responses. We have recently demonstrated that murine LPS in vivo treatment significantly increases Fc?R-dependent clearance of immune complexes (IC). In addition, we and others have reported the induction of adhesion molecules on macrophages and neutrophils by LPS in vivo and by tumour necrosis factor-? (TNF-?) in vitro. The aim of this paper was to investigate CD11b/CD18 participation in LPS enhancing effects on Fc?-dependent functionality of tissue macrophages. Our results have demonstrated that LPS can enhance antibody-dependent cellular cytotoxicity (ADCC) and IC-triggered cytotoxicity (IC-Ctx), two reactions which involve the Fc?-receptor but different lytic mechanisms. In vitro incubation of splenocytes from LPS-treated mice with anti-CD11b/CD18 abrogated ADCC and IC-Ctx enhancement, without affecting Fc?R expression. Similar results were obtained with physiological concentrations of fibrinogen. In this way cytotoxic values of LPS-splenocytes decreased to the basal levels of control mice. Time and temperature requirements for such inhibition strongly suggested that anti-CD11b/CD18 could modulate intracellular signals leading to downregulation of Fc?R functionality. Data presented herein support the hypothesis that functional and/or physical associations between integrins and Fc?R could be critical for the modulation of effector functions during an inflammatory response.

Rubel, C; Miliani De Marval, P; Vermeulen, M; Isturiz, M A; Palermo, M S

1999-01-01

320

Ex vivo magnetofection: A novel strategy for the study of gene function in mouse organogenesis  

PubMed Central

Gene function during mouse development is often studied through the production and analysis of transgenic and knock-out models. However, these techniques are time- and resource-consuming, and require specialized equipment and expertise. We have established a new protocol for functional studies that combines organ culture of explanted fetal tissues with micro-injection and magnetically-induced transfection (“magnetofection”) of gene expression constructs. As proof-of-principle, we magnetofected cDNA constructs into genital ridge tissue as a means of gain-of-function analysis, and shRNA constructs for loss-of-function analysis. Ectopic expression of Sry induced female-to-male sex-reversal, whereas knockdown of Sox9 expression caused male-to-female sex-reversal, consistent with the known functions of these genes. Further, ectopic expression of Tmem184a, a gene of unknown function, in female genital ridges, resulted in failure of gonocytes to enter meiosis. This technique will likely be applicable to the study of gene function in a broader range of developing organs and tissues.

Svingen, Terje; Wilhelm, Dagmar; Combes, Alexander N.; Hosking, Brett; Harley, Vincent R.; Sinclair, Andrew H.; Koopman, Peter

2010-01-01

321

Downregulation of the Antigen Presenting Cell Function(s) of Pulmonary Dendritic Cells In Vivo by Resident Alveolar Macrophages  

Microsoft Academic Search

Sllnllnal~ Class II major histocompatibility complex (Ia)-bearing dendritic cells (DC) from airway epithelium and lung parenchyma express low-moderate antigen presenting cell (APC) activity when freshly isolated. However, this function is markedly upregulated during overnight culture in a manner analogous to epidermal Langerhans cells. The in vitro \\

Patrick G. Holt; Jane Oliver; Natalie Bilyk; Christine McMenamin; Paul G. McMenamin; Georg Kraal

1993-01-01

322

Factors affecting the occurrence of postpartum prolonged luteal activity in clinically healthy high-producing dairy cows.  

PubMed

The objective was to characterize risk factors affecting the occurrence of prolonged luteal phase (PLP) in postpartum, clinically healthy, high-producing dairy cows. Transrectal ultrasound examinations of the reproductive tract were performed twice weekly, from the 1st to 8th wk after calving in 151 multiparous clinically healthy lactating Holstein cows (mean ± SD of peak milk yield = 56.7 ± 7.4 kg). Serum samples were collected twice weekly to measure progesterone and every 2 wk to detect ?-hydroxybutyrate (?HB), and ?1-acid glycoprotein (AGP). Body condition score (BCS) was recorded weekly after calving. Based on the serum progesterone profile, 52 (34.4%) cows had normal ovarian activity (NLA), whereas 36 (23.8%) cows had a prolonged luteal phase (PLP), the most prevalent type of abnormal pattern of luteal activity. Furthermore, 63 cows with short luteal activity, delayed first ovulation, or cystic ovaries were excluded from this study. Serum AGP concentrations, as an indication of postpartum chronic endometritis, were not different (P > 0.05) between cows with NLA and PLP. Categories of peak milk yields (kg) were positively correlated with the incidence (%) of cows with PLP (r = 0.87, P = 0.02). Furthermore, milk yield peak, day of milk yield peak, mean milk yield (8 wk in milk), and milk yield on the expected day of luteolysis were higher (P < 0.05) in cows with PLP than NLA, and cows with PLP had greater loss of BCS (P = 0.007) than those with NLA. The likelihood of cows with PLP decreased by 0.9-fold for every 1 d delay of commencement of luteal activity (C-LA). Moreover, the likelihood of cows with PLP increased by 1.8-fold for each 1 mmol/L increase in the 1st wk serum ?HB concentrations. In conclusion, higher mean of milk yield, greater BCS loss, earlier C-LA, and later peak milk yield were the major risk factors affecting the occurrence of postpartum PLP in clinically healthy, high-producing dairy cows. PMID:21958642

Kafi, Mojtaba; Mirzaei, Abdolah; Tamadon, Amin; Saeb, Mehdi

2011-09-29

323

Oral micronized progesterone combined with vaginal progesterone gel for luteal support.  

PubMed

The aim of the present study was to compare the efficacy and satisfaction rate of combined therapy of oral micronized progesterone capsules and vaginal progesterone gel versus monotherapy with vaginal progesterone gel in luteal support. A case-control study was performed on a total number of 370 women aged <45 years undergoing IVF-ET treatment. The patients received either combination of Crinone 8% vaginal gel, 90 mg daily dose and Utrogestan oral capsules 3 x 100 mg, or Crinone 8% vaginal gel, 90 mg daily. Progesterone supplementation begun on the day of oocyte retrieval and continued until pregnancy was tested and in the case of pregnancy until week 8. The comparable rates of ongoing pregnancies were noted with use of combined-progesterone therapy (39.5%) and progesterone-monotherapy (33.5%). Abortion rate (6.4% vs. 15.6%) was significantly lower with the use of combined therapy. Tolerability and satisfaction of both supplements was almost equal but bleeding occurred more frequently in the progesterone-monotherapy group. In conclusion, the efficacy, satisfaction and tolerability of combined and vaginal progesterone supplements were comparable, but bleeding in early pregnancy and abortion rate presented more frequently with the use of vaginal progesterone. PMID:21504340

Tomic, Vlatka; Tomic, Jozo; Klaic, Djurdja Zigmundovac

2011-04-19

324

Corpus luteal contribution to maternal pregnancy physiology and outcomes in assisted reproductive technologies.  

PubMed

Investigations in the rat model of pregnancy indicate an important role for the corpus luteal (CL) hormone relaxin in the maternal circulatory and osmoregulatory changes in pregnancy, which are epitomized by profound vasodilation and modest hypoosmolality, respectively. In a pilot study of infertile women who became pregnant through donor eggs, in vitro fertilization, and embryo transfer, the gestational rise in glomerular filtration and fall in plasma osmolality were markedly subdued. Because these women were infertile, they lacked a CL and circulating relaxin (and possibly other vasoactive CL hormones). Based on these findings in pregnant rats and women, we hypothesize that infertile women conceiving through donor eggs will have overall subdued circulatory changes (e.g., attenuated reduction in systemic vascular resistance and subdued increase in cardiac output) particularly during early pregnancy when CL hormones predominate before the full development and maturation of the placenta. In contrast, infertile women conceiving by autologous eggs retrieved after ovarian stimulation and fresh embryo transfer may have a relatively hyperdynamic circulation due to the presence of many CL (up to 20 or more) and higher circulating levels of vasodilatory ovarian hormones such as relaxin. Emerging evidence suggests that women undergoing Assisted Reproductive Technologies (ART) have increased risk for adverse pregnancy outcomes such as preeclampsia and small for gestational-age babies. This increased risk may be partly caused by the maternal milieu, which is not physiological in ART pregnancies due to the abnormal status of the CL. PMID:23100030

Conrad, Kirk P; Baker, Valerie L

2012-10-24

325

Geometric modeling, functional parameter calculation, and visualization of the in-vivo distended rectal wall  

Microsoft Academic Search

The rectum can distend to accommodate stool, and contracts in response to distention during defecation. Rectal motor dysfunctions are implicated in the pathophysiology of functional defecation disorders and fecal incontinence. These rectal motor functions can be studied by intra-luminal measurements of pressure by manometry, or combined with volume during rectal balloon distention. Pressure-volume (p-v) relationships provide a global index of

Clifton R. Haider; Armando Manduca; Jon J. Camp; Joel G. Fletcher; Richard A. Robb; Adil E. Bharucha

2006-01-01

326

Pharmacokinetic and toxicological evaluation of multi-functional thiol-6-fluoro-6-deoxy-D-glucose gold nanoparticles in vivo.  

PubMed

We synthesized a novel, multi-functional, radiosensitizing agent by covalently linking 6-fluoro-6-deoxy-D-glucose (6-FDG) to gold nanoparticles (6-FDG-GNPs) via a thiol functional group. We then assessed the bio-distribution and pharmacokinetic properties of 6-FDG-GNPs in vivo using a murine model. At 2 h, following intravenous injection of 6-FDG-GNPs into the murine model, approximately 30% of the 6-FDG-GNPs were distributed to three major organs: the liver, the spleen and the kidney. PEGylation of the 6-FDG-GNPs was found to significantly improve the bio-distribution of 6-FDG-GNPs by avoiding unintentional uptake into these organs, while simultaneously doubling the cellular uptake of GNPs in implanted breast MCF-7 adenocarcinoma. When combined with radiation, PEG-6-FDG-GNPs were found to increase the apoptosis of the MCF-7 breast adenocarinoma cells by radiation both in vitro and in vivo. Pharmacokinetic data indicate that GNPs reach their maximal concentrations at a time window of two to four hours post-injection, during which optimal radiation efficiency can be achieved. PEG-6-FDG-GNPs are thus novel nanoparticles that preferentially accumulate in targeted cancer cells where they act as potent radiosensitizing agents. Future research will aim to substitute the (18)F atom into the 6-FDG molecule so that the PEG-6-FDG-GNPs can also function as radiotracers for use in positron emission tomography scanning to aid cancer diagnosis and image guided radiation therapy planning. PMID:22922305

Roa, Wilson; Xiong, Yeping; Chen, Jie; Yang, Xiaoyan; Song, Kun; Yang, Xiaohong; Kong, Beihua; Wilson, John; Xing, James Z

2012-08-24

327

Pharmacokinetic and toxicological evaluation of multi-functional thiol-6-fluoro-6-deoxy-d-glucose gold nanoparticles in vivo  

NASA Astrophysics Data System (ADS)

We synthesized a novel, multi-functional, radiosensitizing agent by covalently linking 6-fluoro-6-deoxy-d-glucose (6-FDG) to gold nanoparticles (6-FDG-GNPs) via a thiol functional group. We then assessed the bio-distribution and pharmacokinetic properties of 6-FDG-GNPs in vivo using a murine model. At 2 h, following intravenous injection of 6-FDG-GNPs into the murine model, approximately 30% of the 6-FDG-GNPs were distributed to three major organs: the liver, the spleen and the kidney. PEGylation of the 6-FDG-GNPs was found to significantly improve the bio-distribution of 6-FDG-GNPs by avoiding unintentional uptake into these organs, while simultaneously doubling the cellular uptake of GNPs in implanted breast MCF-7 adenocarcinoma. When combined with radiation, PEG-6-FDG-GNPs were found to increase the apoptosis of the MCF-7 breast adenocarinoma cells by radiation both in vitro and in vivo. Pharmacokinetic data indicate that GNPs reach their maximal concentrations at a time window of two to four hours post-injection, during which optimal radiation efficiency can be achieved. PEG-6-FDG-GNPs are thus novel nanoparticles that preferentially accumulate in targeted cancer cells where they act as potent radiosensitizing agents. Future research will aim to substitute the 18F atom into the 6-FDG molecule so that the PEG-6-FDG-GNPs can also function as radiotracers for use in positron emission tomography scanning to aid cancer diagnosis and image guided radiation therapy planning.

Roa, Wilson; Xiong, Yeping; Chen, Jie; Yang, Xiaoyan; Song, Kun; Yang, Xiaohong; Kong, Beihua; Wilson, John; Xing, James Z.

2012-09-01

328

Radiofrequency time-domain EPR imaging: instrumentation development and recent results in functional physiological in vivo imaging  

NASA Astrophysics Data System (ADS)

Electron Paramagnetic Resonance is an emerging technique finding applications in functional physiological imaging. Traditionally EPR imaging developed as a CW (continuous wave) technique involving the measurement of free radical distribution in vivo using constant frequency and field-sweep modality almost identical to the early developments of MRI. As in CT and PET this involved the generation of projections in presence of gradients and the reconstruction of images via filtered back-projection. The large line-width and the concomitant short relaxation times posed a serious challenge for the development of time-domain methods akin to modern pulsed NMR & MRI. With the recent availability of narrow line stable non-toxic radicals based on triarylmethyl (TAM), ultra fast data acquisition systems (signal digitizer and summer), very fast electronic switches and low-noise amplifiers, we have developed time-domain imaging schemes in EPR operating in the radiofrequency region Using a novel pure-phase encoding scheme, we are able to generate 2 and 3 dimensional spatial images and spectral-spatial images that adds an additional functional dimension to these images. The special space-encoding scheme with fast gradient ramping allow rapid in vivo imaging of small animals with superior spatial and functional information with good temporal resolution that can provide valuable physiological and pharmacokinetic insight. Our main thrust has been in the investigation of tumor hypoxia and tumor reoxygenation for the purpose of minimizing the radiation dose for maximum tumor cell killing. These and some of the allied imaging methods, and results from tumor investigation will be presented.

Subramanian, Sankaran; Devasahayam, Nallathamby; Krishna, M. C.

2007-03-01

329

In vivo and in vitro function of human UDP-galactose 4?-epimerase variants  

PubMed Central

Type III galactosemia results from reduced activity of the enzyme UDP-galactose 4?-epimerase. Five disease-associated alleles (G90E, V94M, D103G, N34S and L183P) and three artificial alleles (Y105C, N268D, and M284K) were tested for their ability to alleviate galactose-induced growth arrest in a Saccharomyces cerevisiae strain which lacks endogenous UDP-galactose 4?-epimerase. For all of these alleles, except M284K, the ability to alleviate galactose sensitivity was correlated with the UDP-galactose 4?-epimerase activity detected in cell extracts. The M284K allele, however, was able to substantially alleviate galactose sensitivity, but demonstrated near-zero activity in cell extracts. Recombinant expression of the corresponding protein in Escherichia coli resulted in a protein with reduced enzymatic activity and reduced stability towards denaturants in vitro. This lack of stability may result from the introduction of an unpaired positive charge into a bundle of three ?-helices near the surface of the protein. The disparities between the in vivo and in vitro data for M284K-hGALE further suggest that there are additional, stabilising factors present in the cell. Taken together, these results reinforce the need for care in the interpretation of in vitro, enzymatic diagnostic tests for type III galactosemia.

McCorvie, Thomas J.; Wasilenko, Jamie; Liu, Ying; Fridovich-Keil, Judith L.; Timson, David J.

2011-01-01

330

In vivo functional chronic imaging of a small animal model using optical-resolution photoacoustic microscopy  

PubMed Central

Optical-resolution photoacoustic microscopy (OR-PAM) has been validated as a valuable tool for label-free volumetric microvascular imaging. More importantly, the advantages of noninvasiveness and measurement consistency suggest the use of OR-PAM for chronic imaging of intact microcirculation. Here, such chronic imaging is demonstrated for the first time by monitoring the healing process of laser-induced microvascular lesions in a small animal model in vivo. The central part of a 1 mm by 1 mm region in a nude mouse ear was treated under a continuous-wave laser to create a microvascular lesion for chronic study. The region of interest was imaged before the laser treatment, immediately after the treatment, and throughout the healing process using both the authors’ OR-PAM system and a commercial transmission-mode optical microscope. Three-dimensional microvascular morphology and blood oxygenation information were imaged simultaneously at capillary-level resolution. Transmission-mode optical microscopic images were acquired for comparison. OR-PAM has potential important applications in microcirculatory physiology or pathophysiology, tumor angiogenesis, laser microsurgery, and neuroscience.

Hu, Song; Maslov, Konstantin; Wang, Lihong V.

2009-01-01

331

Effects of ex vivo ?-Tocopherol on Airway Macrophage Function in Healthy and Mild Allergic Asthmatics.  

PubMed

Elevated inflammation and altered immune responses are features found in atopic asthmatic airways. Recent studies indicate ?-tocopherol (GT) supplementation can suppress airway inflammation in allergic asthma. We studied the effects of in vitro GT supplementation on receptor-mediated phagocytosis and expression of cell surface molecules associated with innate and adaptive immunity on sputum-derived macrophages. Cells from nonsmoking healthy (n = 6) and mild house dust mite-sensitive allergic asthmatics (n = 6) were treated ex vivo with GT (300 µM) or saline (control). Phagocytosis of opsonized zymosan A bioparticles (Saccharomyces cerevisiae) and expression of surface molecules associated with innate and adaptive immunity were assessed using flow cytometry. GT caused significantly decreased (p < 0.05) internalization of attached zymosan bioparticles and decreased (p < 0.05) macrophage expression of CD206, CD36 and CD86 in allergic asthmatics but not in controls. Overall, GT caused downregulation of both innate and adaptive immune response elements, and atopic status appears to be an important factor. PMID:23689260

Geiser, Marianne; Lay, John C; Bennett, William D; Zhou, Haibo; Wang, Xiaoyan; Peden, David B; Alexis, Neil E

2013-05-08

332

Efficient inhibition of miR-155 function in vivo by peptide nucleic acids  

PubMed Central

MicroRNAs (miRNAs) play an important role in diverse physiological processes and are potential therapeutic agents. Synthetic oligonucleotides (ONs) of different chemistries have proven successful for blocking miRNA expression. However, their specificity and efficiency have not been fully evaluated. Here, we show that peptide nucleic acids (PNAs) efficiently block a key inducible miRNA expressed in the haematopoietic system, miR-155, in cultured B cells as well as in mice. Remarkably, miR-155 inhibition by PNA in primary B cells was achieved in the absence of any transfection agent. In mice, the high efficiency of the treatment was demonstrated by a strong overlap in global gene expression between B cells isolated from anti-miR-155 PNA-treated and miR-155-deficient mice. Interestingly, PNA also induced additional changes in gene expression. Our analysis provides a useful platform to aid the design of efficient and specific anti-miRNA ONs for in vivo use.

Fabani, Martin M.; Abreu-Goodger, Cei; Williams, Donna; Lyons, Paul A.; Torres, Adrian G.; Smith, Kenneth G. C.; Enright, Anton J.; Gait, Michael J.; Vigorito, Elena

2010-01-01

333

In vivo functional efficacy of tumor-specific T cells expanded using HLA-Ig based artificial antigen presenting cells (aAPC)  

Microsoft Academic Search

Adoptive immunotherapy for treatment of cancers and infectious diseases is often hampered by a high degree of variability\\u000a in the final T cell product and in the limited in vivo function and survival of ex vivo expanded antigen-specific cytotoxic\\u000a T cells (CTL). This has stimulated interest in development of standardized artificial antigen presenting cells (aAPC) to reliably\\u000a expand antigen specific

Malarvizhi Durai; Christine Krueger; Zhaohui Ye; Linzhao Cheng; Andreas Mackensen; Mathias Oelke; Jonathan P. Schneck

2009-01-01

334

In Vivo Characterization of Traumatic Brain Injury Neuropathology with Structural and Functional Neuroimaging  

PubMed Central

Quantitative neuroimaging is increasingly used to study the effects of traumatic brain injury (TBI) on brain structure and function. This paper reviews quantitative structural and functional neuroimaging studies of patients with TBI, with an emphasis on the effects of diffuse axonal injury (DAI), the primary neuropathology in TBI. Quantitative structural neuroimaging has evolved from simple planometric measurements through targeted region-of-interest analyses to whole-brain analysis of quantified tissue compartments. Recent studies converge to indicate widespread volume loss of both gray and white matter in patients with moderate-to-severe TBI. These changes can be documented even when patients with focal lesions are excluded. Broadly speaking, performance on standard neuropsychological tests of speeded information processing are related to these changes, but demonstration of specific brain-behavior relationships requires more refined experimental behavioral measures. The functional consequences of these structural changes can be imaged with activation functional neuroimaging. Although this line of research is at an early stage, results indicate that TBI causes a more widely dispersed activation in frontal and posterior cortices. Further progress in analysis of the consequences of TBI on neural structure and function will require control of variability in neuropathology and behavior.

LEVINE, BRIAN; FUJIWARA, ESTHER; O'CONNOR, CHARLENE; RICHARD, NADINE; KOVACEVIC, NATASA; MANDIC, MARINA; RESTAGNO, ADRIANA; EASDON, CRAIG; ROBERTSON, IAN H.; GRAHAM, SIMON J.; CHEUNG, GORDON; GAO, FUQIANG; SCHWARTZ, MICHAEL L.; BLACK, SANDRA E.

2007-01-01

335

Mood states, sympathetic activity, and in vivo beta-adrenergic receptor function in a normal population.  

PubMed

The purpose of this study was to examine the relationship between mood states and beta-adrenergic receptor function in a normal population. We also examined if sympathetic nervous system activity is related to mood states or beta-adrenergic receptor function. Sixty-two participants aged 25-50 years were enrolled in this study. Mood states were assessed using the Profile of Mood States (POMS). Beta-adrenergic receptor function was determined using the chronotropic 25 dose isoproterenol infusion test. Level of sympathetic nervous system activity was estimated from 24-hr urine norepinephrine excretion. Higher tension-anxiety, depression-dejection, and anger-hostility were related to decreased beta-adrenergic receptor sensitivity (i.e., higher chronotropic 25 dose values), but tension-anxiety was the only remaining independent predictor of beta-adrenergic receptor function after controlling for age, gender, ethnicity, and body mass index (BMI). Urinary norepinephrine excretion was unrelated to either mood states or beta-adrenergic receptor function. These findings replicate previous reports that anxiety is related to decreased (i.e., desensitized) beta-adrenergic receptor sensitivity, even after controlling for age, gender, ethnicity, and body mass index. PMID:17583588

Yu, Bum-Hee; Kang, Eun-Ho; Ziegler, Michael G; Mills, Paul J; Dimsdale, Joel E

2008-01-01

336

Photoinactivation of functional photosystem II and D1-protein synthesis in vivo are independent of the modulation of the photosynthetic apparatus by growth irradiance  

Microsoft Academic Search

To investigate whether the in-vivo photoinhibition of photosystem II (PSII) function by excess light is an intrinsic property of PSII, the maximal photochemical efficiency of PSII (Fv\\/Fm) and the content of functional PSII (measured by repetitive flash yield of oxygen evolution) were determined in leaves of pea (Pisum sativum L.), grown in 50 (low light), 250 (medium light), and 650

Youn-Il Park; Jan M. Anderson; Wah Soon Chow

1996-01-01

337

Toll-like receptor 3 regulates cord blood-derived endothelial cell function in vitro and in vivo.  

PubMed

Circulating endothelial progenitor cells (cEPC) are capable of homing to neovascularisation sites, in which they proliferate and differentiate into endothelial cells. Transplantation of cEPC-derived cells, in particular those isolated from umbilical cord blood (UCB), has emerged as a promising approach in the treatment of cardio-vascular diseases. After in vivo transplantation, these cells may be exposed to local or systemic inflammation or pathogens, of which they are a common target. Because Toll-like receptors (TLR) are critical in detecting pathogens and in initiating inflammatory responses, we hypothesized that TLR may govern UCB cEPC-derived cells function. While these cells expressed almost all TLR, we found that only TLR3 dramatically impaired cell properties. TLR3 activation inhibited cell proliferation, modified cell cycle entry, impaired the in vitro angiogenic properties and induced pro-inflammatory cytokines production. The anti-angiogenic effect of TLR3 activation was confirmed in vivo in a hind-limb ischemic mice model. Moreover, TLR3 activation consistently leads to an upregulation of miR-29b, -146a and -155 and to a deregulation of cytoskeleton and cell cycle regulator. Hence, TLR3 activation is likely to be a key regulator of cEPC-derived cells properties. PMID:23748743

Grelier, Aurore; Cras, Audrey; Balitrand, Nicole; Delmau, Catherine; Lecourt, Séverine; Lepelletier, Yves; Riesterer, Hélène; Freida, Delphine; Lataillade, Jean-Jacques; Lebousse-Kerdiles, Marie-Caroline; Cuccini, Wendy; Peffault de Latour, Regis; Marolleau, Jean-Pierre; Uzan, Georges; Larghero, Jérôme; Vanneaux, Valérie

2013-06-08

338

Structure-function studies of STAR family Quaking proteins bound to their in vivo RNA target sites  

PubMed Central

Mammalian Quaking (QKI) and its Caenorhabditis elegans homolog, GLD-1 (defective in germ line development), are evolutionarily conserved RNA-binding proteins, which post-transcriptionally regulate target genes essential for developmental processes and myelination. We present X-ray structures of the STAR (signal transduction and activation of RNA) domain, composed of Qua1, K homology (KH), and Qua2 motifs of QKI and GLD-1 bound to high-affinity in vivo RNA targets containing YUAAY RNA recognition elements (RREs). The KH and Qua2 motifs of the STAR domain synergize to specifically interact with bases and sugar-phosphate backbones of the bound RRE. Qua1-mediated homodimerization generates a scaffold that enables concurrent recognition of two RREs, thereby plausibly targeting tandem RREs present in many QKI-targeted transcripts. Structure-guided mutations reduced QKI RNA-binding affinity in vitro and in vivo, and expression of QKI mutants in human embryonic kidney cells (HEK293) significantly decreased the abundance of QKI target mRNAs. Overall, our studies define principles underlying RNA target selection by STAR homodimers and provide insights into the post-transcriptional regulatory function of mammalian QKI proteins.

Teplova, Marianna; Hafner, Markus; Teplov, Dmitri; Essig, Katharina; Tuschl, Thomas; Patel, Dinshaw J.

2013-01-01

339

Effects of sulfamethoxazole and trimethoprim on human neutrophil and lymphocyte functions in vitro: in vivo effects of co-trimoxazole.  

PubMed Central

The effects of sulfamethoxazole and trimethoprim individually and in combination on in vitro neutrophil random migration, chemotaxis to autologous endotoxin-activated serum and the synthetic chemotactic tripeptide N-formyl-L-methionyl-L-leucyl-L-phenylalanine, phagocytosis and postphagocytic Nitro Blue Tetrazolium reduction, glycolysis, hexose monophosphate shunt activity, myeloperoxidase-mediated protein iodination, hydrogen peroxide production, and degranulation were assessed. The effects on lymphocyte mitogen-induced transformation were also evaluated. It was found that the test agents individually and in combination at high concentrations (> 100 microgram/ml) caused the inhibition of neutrophil postphagocytic myeloperoxidase-mediated protein iodination, which was related to the interference with H2O2 formation as the enzyme per se was unaffected. Both agents caused the inhibition of lymphocyte transformation at high concentrations (> 100 microgram/ml). In vivo studies before and after the ingestion of co-trimoxazole by three individuals showed no inhibition of any of the neutrophil functions tested. The inhibition of lymphocyte transformation was observed in one individual after the ingestion of the chemotherapeutic agent. These findings indicate that the concentrations which inhibit neutrophil H2O2 production and lymphocyte transformation in vitro are not attainable in vivo.

Anderson, R; Grabow, G; Oosthuizen, R; Theron, A; Van Rensburg, A J

1980-01-01

340

Relationships between insulin-like growth factor-I, milk yield, body condition score, and postpartum luteal activity in high-producing dairy cows.  

PubMed

The relations between body condition score (BCS), milk yield, serum insulin-like growth factor-I (IGF-I) profile, and luteal activity were investigated in postpartum dairy cows. Seventy-one healthy high-producing multiparous Holstein cows were subjected to transrectal ultrasound scanning twice weekly from the first to the eighth week postpartum. Blood samples were collected twice weekly to measure serum progesterone (P4) and every 2 weeks to detect serum IGF-I concentrations. BCS was monitored weekly after calving. Cows with serum P4 concentrations ?1 ng/ml on at least two consecutive samplings were considered to have commenced luteal activity. Commencement of luteal activity (C-LA) was observed earlier than 45 days postpartum in 71.8% of cows while 28.2% showed C-LA later than 45 days. Prolonged luteal phase was the most common abnormal pattern of luteal activity observed. Cows with a C-LA earlier than 45 days postpartum had higher (P???0.05) mean serum concentrations of IGF-I than those with later C-LA. In addition, cows which showed C-LA earlier than 45 days postpartum had more optimal productive indices including shorter calving to conception interval and calving to first service interval (P???0.05), and fewer services per conception (P?=?0.07). C-LA was significantly later in cows that lost more than 0.5 BCS units within 3 weeks postpartum than in those that lost less than 0.5 units BCS during the same interval (P?=?0.02). We conclude that high-producing dairy cows with higher postpartum serum IGF-I concentrations have earlier commencement and normal luteal activity, and better reproductive performance. Severity and duration of BCS loss adversely affect commencement of luteal activity. PMID:20623186

Tamadon, Amin; Kafi, Mojtaba; Saeb, Mehdi; Mirzaei, Abdolah; Saeb, Saedeh

2010-07-11

341

In vivo two-photon uncaging of glutamate revealing the structure-function relationships of dendritic spines in the neocortex of adult mice  

PubMed Central

Abstract Two-photon (2P) uncaging of caged neurotransmitters can efficiently stimulate individual synapses and is widely used to characterize synaptic functions in brain slice preparations. Here we extended 2P uncaging to neocortical pyramidal neurons in adult mice in vivo where caged glutamate was applied from the pial surface. To validate the methodology, we applied a small fluorescent probe using the same method, and confirmed that its concentrations were approximately homogenous up to 200 ?m below the cortical surface, and that the extracellular space of the neocortex was as large as 22%. In fact, in vivo whole-cell recording revealed that 2P glutamate uncaging could elicit transient currents (2pEPSCs) very similar to excitatory postsynaptic currents (EPSCs). A spatial resolution of glutamate uncaging was 0.6–0.8 ?m up to the depth of 200 ?m, and in vivo 2P uncaging was able to stimulate single identified spines. Automated three-dimensional (3-D) mapping of such 2pEPSCs which covered the surfaces of dendritic branches revealed that functional AMPA receptor expression was stable and proportional to spine volume. Moreover, in vivo 2P Ca2+ imaging and uncaging suggested that the amplitudes of glutamate-induced Ca2+ transients were inversely proportional to spine volume. Thus, the key structure–function relationships hold in dendritic spines in adult neocortex in vivo, as in young hippocampal slice preparations. In vivo 2P uncaging will be a powerful tool to investigate properties of synapses in the neocortex.

Noguchi, Jun; Nagaoka, Akira; Watanabe, Satoshi; Ellis-Davies, Graham C R; Kitamura, Kazuo; Kano, Masanobu; Matsuzaki, Masanori; Kasai, Haruo

2011-01-01

342

In Vitro and In Vivo Evaluation of a Novel Ferrocyanide Functionalized Nanopourous Silica Decorporation Agent for Cesium (Cs) in Rats  

PubMed Central

Novel decorporation agents are being developed to protect against radiological terrorist attacks. These sorbents, known as the self-assembled monolayer on mesoporous supports (SAMMS™), are hybrid materials where differing organic moieties are grafted onto mesoporous silica (SiO2). In vitro experiments focused on the evaluation, and optimization of SAMMS for capturing radiocesium (137Cs); therefore based on these studies, a ferrocyanide copper (FC-Cu-EDA)-SAMMS was advanced for in vivo evaluation. In vivo experiments were conducted comparing the performance of the SAMMS vs. insoluble Prussian blue. Groups of jugular cannulated rats (4/treatment) were evaluated. Animals in group I were administered 137Cs chloride (~40 ?g/kg) by intravenous (iv) injection or oral gavage; Group II animals were administered pre-bound 137Cs- SAMMS or sequential 137Cs chloride + SAMMS (~61 ng/kg) by oral gavage; and Group III was orally administered 137Cs chloride (~61 ng/kg) followed by either 0.1 g of SAMMS or Prussian blue. Following dosing, the rats were maintained in metabolism cages for 72 hour and blood, urine and fecal samples were collected for 137Cs analysis (gamma counting). Rats were then humanely euthanized, and selected tissues analyzed. Orally administered 137Cs chloride was rapidly and well absorbed (~100% relative to iv dose), and the pharmacokinetics (blood, urine, feces & tissues) were very comparable to the iv dose group. For both exposures the urine and feces accounted for 20 and 3% of the dose, respectively. The prebound 137Cs-SAMMS was retained primarily within the feces (72% of the dose), with ~1.4% detected in the urine, suggesting that the 137Cs remained tightly bound to SAMMS. SAMMS & Prussian blue both effectively captured available 137Cs in the gut with feces accounting for 80–88% of the administered dose, while less than 2% was detected in the urine. This study suggests that the functionalized SAMMS outperforms Prussian blue in vitro at low pH, but demonstrates comparable in vivo sequestration efficacy at low exposure concentrations. The comparable response may be the result of the low 137Cs chloride dose and high sorbent dosage that was utilized. Future studies are planned to optimize SAMMS in vivo performance over a broader range of doses and conditions.

Timchalk, Charles; Creim, Jeffrey A; Sukwarotwat, Vichaya; Wiacek, Robert; Addleman, R Shane; Fryxell, Glen E; Yantasee, Wassana

2009-01-01

343

A multifunctional turnip crinkle virus replication enhancer revealed by in vivo functional SELEX.  

PubMed

The motif1-hairpin (M1H), located on (-)-strands of Turnip Crinkle Virus (TCV)-associated satellite RNA C (satC), is a replication enhancer and recombination hotspot. Results of in vivo genetic selection (SELEX: systematic evolution of ligands by exponential enrichment), where 28 bases of the M1H were randomized and then subjected to selection in plants, revealed that most winners contained one to three short motifs, many of which in their (-)-sense orientation are found in TCV and satC (-)-strand promoter elements. Ability to replicate in protoplasts correlated with fitness to accumulate in plants with one significant exception. Winner UC, containing only a seven-base replacement sequence, was the second most fit winner, yet replicated no better than a 28-base random replacement sequence. Fitness of satC containing different M1H replacement sequences could be due to enhanced satC replication or enhanced ability to affect TCV movement, since satC interferes with TCV virion accumulation, which is correlated with enhanced movement to younger tissue. Cells inoculated with TCV and UC accumulated fewer virions when compared to other winners that replicated better in protoplasts but were less fit in plants. UC, and other first and second round winners, contained structures that were on average 33% more stable in their (+)-strand orientation, and most formed hairpins with a A-rich sequence at the base. These results suggest that M1H replacement sequences contribute to the fitness of satC by either containing (-)-strand elements that enhance satRNA replication and/or a (+)-strand hairpin flanked with single-stranded sequence that enhances TCV movement. PMID:12547189

Zhang, Guohua; Simon, Anne E

2003-02-01

344

Isolation and functional properties of murine hematopoietic stem cells that are replicating in vivo.  

PubMed

Hematopoietic stem cells (HSC) are multipotent cells that reside in the bone marrow and replenish all adult hematopoietic lineages throughout the lifetime of the animal. While experimenting with staining of murine bone marrow cells with the vital dye, Hoechst 33342, we discovered that display of Hoechst fluorescence simultaneously at two emission wavelengths revealed a small and distinct subset of whole bone marrow cells that had phenotypic markers of multipotential HSC. These cells were shown in competitive repopulation experiments to contain the vast majority of HSC activity from murine bone marrow and to be enriched at least 1,000-fold for in vivo reconstitution activity. Further, these Hoechst-stained side population (SP) cells were shown to protect recipients from lethal irradiation at low cell doses, and to contribute to both lymphoid and myeloid lineages. The formation of the Hoechst SP profile was blocked when staining was performed in the presence of verapamil, indicating that the distinctly low staining pattern of the SP cells is due to a multidrug resistance protein (mdr) or mdr-like mediated efflux of the dye from HSC. The ability to block the Hoechst efflux activity also allowed us to use Hoechst to determine the DNA content of the SP cells. Between 1 and 3% of the HSC were shown to be in S-G2M. This also enabled the purification of the G0-G1 and S-G2M HSC had a reconstitution capacity equivalent to quiescent stem cells. These findings have implications for models of hematopoietic cell development and for the development of genetic therapies for diseases involving hematopoietic cells. PMID:8666936

Goodell, M A; Brose, K; Paradis, G; Conner, A S; Mulligan, R C

1996-04-01

345

Vorinostat increases expression of functional norepinephrine transporter in neuroblastoma in vitro and in vivo model systems  

PubMed Central

Purpose Histone deacetylase (HDAC) inhibition causes transcriptional activation or repression of several genes that in turn can influence the biodistribution of other chemotherapeutic agents. Here, we hypothesize that the combination of vorinostat, a HDAC inhibitor, with 131I-metaiodobenzylguanidine (MIBG) would lead to preferential accumulation of the latter in neuroblastoma (NB) tumors via increased expression of the human norepinephrine transporter (NET). Experimental Design In vitro and in vivo experiments examined the effect of vorinostat on the expression of NET, an uptake transporter for 131I-MIBG. Human NB cell lines (Kelly and SH-SY-5Y) and NB1691luc mouse xenografts were employed. The upregulated NET protein was characterized for its effect on 123I-MIBG biodistribution. Results Preincubation of NB cell lines, Kelly and SH-SY-5Y, with vorinostat caused dose-dependent increases in NET mRNA and protein levels. Accompanying this was a corresponding dose-dependent increase in MIBG uptake in NB cell lines. Four-fold and 2.5 fold increases were observed in Kelly and SH-SY-5Y cells, respectively, pre-treated with vorinostat in comparison to untreated cells. Similarly, NB xenografts, created by intravenous tail vein injection of NB1691-luc, and harvested from nude mice livers treated with vorinostat (150 mg/kg i.p.) showed substantial increases in NET protein expression. Maximal effect of vorinostat pretreatment in NB xenografts on 123I-MIBG biodistribution was observed in tumors that exhibited enhanced uptake in vorinostat treated (0.062 ± 0.011 ?Ci/(mg tissue-dose injected)) versus untreated mice (0.022 ± 0.003 ?Ci/(mg tissue-dose injected); p < 0.05). Conclusions The results of our study provide preclinical evidence that vorinostat treatment can enhance NB therapy with 131I-MIBG.

More, Swati S.; Itsara, Melissa; Yang, Xiaodong; Geier, Ethan G.; Tadano, Michelle K.; Seo, Youngho; VanBrocklin, Henry F.; Weiss, William A.; Mueller, Sabine; Haas-Kogan, Daphne A.; DuBois, Steven G.; Matthay, Katherine K.; Giacomini, Kathleen M.

2011-01-01

346

In vivo stem cell function of interleukin-3-induced blast cells  

SciTech Connect

The treatment of mice with high doses of 5-fluorouracil (5-FU) results in an enrichment of primitive hematopoietic progenitors. Using this procedure, the authors obtained a new class of murine hematopoietic colonies that had very high secondary plating efficiencies in vitro and could differentiate into not only myeloid cells but also into lymphoid lineage cells. The phenotypes of interleukin-3 (IL-3) induced blast colony cells were Thy-1-positive and lineage-marker-negative. They examined whether these blast colony cells contained primitive hematopoietic stem cells in vivo and could reconstitute hematopoietic tissues in lethally irradiated mice. Blast colony cells could generate macroscopic visible spleen colonies on days 8 and 12, and 5 {times} 10(3) blast cells were sufficient to protect them from lethally irradiation. It was shown that 6 or 8 weeks after transplantation of 5 {times} 10(3) blast cells, donor male cells were detected in the spleen and thymus of the female recipients but not in the bone marrow by Southern blot analysis using Y-encoded DNA probe. After 10 weeks, bone marrow cells were partially repopulated from donor cells. In a congenic mouse system, donor-derived cells (Ly5.2) were detected in the thymus and spleen 6 weeks after transplantation. Fluorescence-activated cell sorter analyses showed that B cells and macrophages developed from donor cells in the spleen. In the thymus, donor-derived cells were found in CD4, CD8 double-positive, single-positive, and double-negative populations. Reconstitution of bone marrow was delayed and myeloid and lymphoid cells were detected 10 weeks after transplantation. These results indicate that IL-3-induced blast cells contain the primitive hematopoietic stem cells capable of reconstituting hematopoietic organs in lethally irradiated mice.

Tsunoda, J.; Okada, S.; Suda, J.; Nagayoshi, K.; Nakauchi, H.; Hatake, K.; Miura, Y.; Suda, T. (Department of Medicine, Jichi Medical School, Tochigi-ken (Japan))

1991-07-15

347

Brain basis of early parent?infant interactions: psychology, physiology, and in vivo functional neuroimaging studies  

Microsoft Academic Search

Parenting behavior critically shapes human infants' current and future behavior. The parent-infant relationship provides infants with their first social experiences, forming templates of what they can expect from others and how to best meet others' expectations. In this review, we focus on the neuro- biology of parenting behavior, including our own functional magnetic resonance imaging (fMRI) brain imaging experiments of

James E. Swain; Jeffrey P. Lorberbaum; Samet Kose

2007-01-01

348

An approach to the functional anatomy of the sacroiliac joints in vivo  

Microsoft Academic Search

Summary This first part of this paper is a review of the literature on the functional anatomy of the sacroiliac joint followed by a preliminary biomechanical study of the fresh post mortem pelvis. The latter was done in order to determine the coefficients of the screw matrix and the position of the instantaneous centers of rotation during the symmetrical movements

B. Lavignolle; J. M. Vital; J. Senegas; J. Destandau; B. Toson; P. Bouyx; P. Morlier; G. Delorme; A. Calabet

1983-01-01

349

Regulation of cytoplasmic dynein function in vivo by the Drosophila Glued complex  

Microsoft Academic Search

The Drosophila Glued gene product shares sequence homology with the p150 component of verte- brate dynactin. Dynactin is a multiprotein complex that stimulates cytoplasmic dynein-mediated vesicle mo- tility in vitro. In this report, we present biochemical, cytological, and genetic evidence that demonstrates a functional similarity between the Drosophila Glued complex and vertebrate dynactin. We show that, similar to the vertebrate

Maura McGrail; Janice Gepner; Andre Silvanovich; Susan Ludmann; Madeline Serr; Thomas S. Hays

1995-01-01

350

In vivo activation of heterophil function in chickens following injection with Salmonella enteritidis-immune lymphokines  

Microsoft Academic Search

We have previously shown that increased re- sistance to Salmonella enteritidis organ infectivity in day-old chicks was conferred by the immunoprophylactic administration of S. enteritidis-immune lymphokines (ILK). This resistance was associated with a significant increase in the number of circulating heterophils 4 h after ILK injection. The objective of the present study was to evaluate heterophil function following the administration

Michael H. Kogut; Edward D. McGruder; Billy M. Hargis; Donald E. Corrier; John A. DeLoach

1995-01-01

351

IN VITRO/IN VIVO COMPARISON OF YOLK SAC FUNCTION AND EMBRYO DEVELOPMENT  

EPA Science Inventory

Yolk sac function and development of rat embryos grown in vitro for 24 hrs starting on day 10.5 were compared to those of embryos grown in utero. he embryos grown in vitro had significantly fewer somites, shorter crown-rump length and smaller yolk sac diameter when compared to th...

352

Functional architecture in monkey inferotemporal cortex revealed by in vivo optical imaging  

Microsoft Academic Search

To investigate the functional organization in the monkey inferotemporal cortex, which is the last exclusively visual area along the ventral visual cortical pathway, optical imaging based on intrinsic signals was carried out. We first conducted single-cell recordings with microelectrodes and determined the features critical for the activation of single cells. For the subsequent optical imaging, each critical feature was presented,

Gang Wang; Manabu Tanifuji; Keiji Tanaka

1998-01-01

353

Activation of Mutant Enzyme Function In Vivo by Proteasome Inhibitors and Treatments that Induce Hsp70  

Microsoft Academic Search

Missense mutant proteins, such as those produced in individuals with genetic diseases, are often misfolded and subject to processing by intracellular quality control systems. Previously, we have shown using a yeast system that enzymatic function could be restored to I278T cystathionine ?-synthase (CBS), a cause of homocystinuria, by treatments that affect the intracellular chaperone environment. Here, we extend these studies

Laishram R. Singh; Sapna Gupta; Nicholaas H. Honig; Jan P. Kraus; Warren D. Kruger

2010-01-01

354

Proliferation of Functional Hair Cells in Vivo in the Absence of the Retinoblastoma Protein  

Microsoft Academic Search

In mammals, hair cell loss causes irreversible hearing and balance impairment because hair cells are terminally differentiated and do not regenerate spontaneously. By profiling gene expression in developing mouse vestibular organs, we identified the retinoblastoma protein (pRb) as a candidate regulator of cell cycle exit in hair cells. Differentiated and functional mouse hair cells with a targeted deletion of Rb1

Cyrille Sage; Mingqian Huang; Kambiz Karimi; Gabriel Gutierrez; Melissa A. Vollrath; Duan-Sun Zhang; Jaime García-Añoveros; Philip W. Hinds; Jeffrey T. Corwin; David P. Corey; Zheng-Yi Chen

2005-01-01

355

In vivo analysis of the functions of gamma-tubulin-complex proteins.  

PubMed

To enhance our understanding of the function(s) of gamma-tubulin-complex proteins (GCPs), we identified and analyzed the functions of the Aspergillus nidulans homologs of GCP2-GCP6 (here designated GCPB-GCBF). The gamma-tubulin small complex (gamma-TuSC) components, gamma-tubulin, GCPB and GCPC, are essential for viability and mitotic spindle formation, whereas GCPD-GCPF are not essential for viability, spindle formation or sexual reproduction. GCPD-GCPF function in reducing the frequency of chromosome mis-segregation and in the assembly of large gamma-tubulin complexes. Deletion of any of the gamma-TuSC components eliminates the localization of all GCPs to the spindle pole body (SPB), whereas deletion of GCPD-GCPF does not affect localization of gamma-TuSC components. Thus, GCPD-GCPF do not tether the gamma-TuSC to the SPB, but, rather, the gamma-TuSC tethers them to the SPB. GCPD-GCPF exhibit a hierarchy of localization to the SPB. Deletion of GCPF eliminates GCPD-GCPE localization to the SPB, and deletion of GCPD eliminates GCPE (but not GCPF) localization. All GCPs localize normally in a GCPE deletion. We propose a model for the structure of the gamma-tubulin complex and its attachment to polar microtubule organizing centers. PMID:19861490

Xiong, Yi; Oakley, Berl R

2009-10-27

356

Is there functional vascular information in anatomical MR Sequences? A preliminary in vivo study  

Microsoft Academic Search

According to the type of sequences used, either morphological or dynamic functional study can be performed using magnetic resonance imaging (MRI). The aim of this study is to find out if vascular information found, in dynamic MR sequences, already exists in anatomical MR sequences in the particular case of Legg-Calve-Perthes disease (LCPD). LCPD is due to a loss of circulation

Renaud Winzenrieth; Isabelle Claude; Marie-Christine Hobatho; Guy Sebag

2006-01-01

357

Biological functions of t cell lines with specificity for the intracellular bacterium Listeria monocytogenes in vitro and in vivo  

PubMed Central

Peritoneal exudate T lymphocytes from mice immunized with live Listeria monocytogenes were cloned in double-layer soft agar containing heat- killed L. monocytogenes (lower layer) and syngeneic accessory cells (upper layer). Colony-derived T cells were propagated in vitro in the presence of listerial antigen, syngeneic accessory cells, and T cell growth factor. In vitro proliferation, interleukin secretion, and bystander help for B cells of six such T cell lines and several sublines derived from them were found to be antigen dependent and restricted by the H-2IA locus of the major histocompatibility complex. In vivo, these T cell lines conferred delayed-type hypersensitivity to listerial antigen and protection to live L. monocytogenes. It is concluded that different biological functions of acquired antibacterial immunity can be mediated by a single T cell population.

1982-01-01

358

Docosahexaenoic acid and phosphatidylserine improves the antioxidant activities in vitro and in vivo and cognitive functions of the developing brain.  

PubMed

Fish oil during early postnatal period may modulate the impact of oxidative stress in the developing brain and thus improve memory and cognitive behaviour. This study investigated the impacts of docosahexaenoic acid (DHA, C22:6, n-3) and/or phosphatidylserine (PS) on antioxidant activities in vitro, and the beneficial effects of feeding with DHA and/or PS on antioxidant activities in brain and liver tissues and on the cognitive functions of the developing brain. Results indicated that DHA and/or PS significantly enhanced antioxidant activities and increased cell viabilities in vitro. Feeding with DHA and/or PS supplementation not only significantly improved escape latency of animals, but it also improved the oxidative parameters in the brain, enhanced glutathione peroxidase activity as well as reduced nitric mono-oxide levels in the liver. DHA and PS may serve to protect cells from oxidative stress and further improve learning and memory ability in vivo. PMID:23265497

Chaung, Hso-Chi; Chang, Chin-Dong; Chen, Pi-Hang; Chang, Chia-Jung; Liu, Shyh-Hwa; Chen, Chih-Cheng

2012-11-10

359

HIV Type 1 Infection Up-Regulates TLR2 and TLR4 Expression and Function in Vivo and in Vitro  

PubMed Central

Abstract Toll-like receptors (TLRs) play a critical role in innate immunity against pathogens. Their stimulation induces the activation of NF-?B, an important inducer of HIV-1 replication. In recent years, an increasing number of studies using several cells types from HIV-infected patients indicate that TLRs play a key role in regulating the expression of proinflammatory cytokines and viral pathogenesis. In the present study, the effect of HIV-1 stimulation of monocyte-derived macrophage (MDM) and peripheral blood mononuclear cell (PBMC) subpopulations from healthy donors on the expression and functions of TLR2 and TLR4 was examined. In addition, and to complete the in vitro study, the expression pattern of TLR2 and TLR4 in 49 HIV-1-infected patients, classified according to viral load and the use of HAART, was determined and compared with 25 healthy subjects. An increase of TLR expression and production of proinflammatory cytokines were observed in MDMs and PBMCs infected with HIV-1 in vitro and in response to TLR stimulation, compared to the mock. In addition, an association between TLR expression and up-regulation of CD80 in plasmacytoid dendritic cells (pDCs) was observed. The ex vivo analysis indicated increased expression of TLR2 and TLR4 in myeloid dendritic cells (mDCs), but only of TLR2 in monocytes obtained from HIV-1-infected patients, compared to healthy subjects. Remarkably, the expression was higher in cells from patients who do not use HAART. In monocytes, there was a positive correlation between both TLRs and viral load, but not CD4+ T cell numbers. Together, our in vitro and ex vivo results suggest that TLR expression and function can be up-regulated in response to HIV-1 infection and could affect the inflammatory response. We propose that modulation of TLRs represents a mechanism to promote HIV-1 replication or AIDS progression in HIV-1-infected patients.

Hernandez, Juan C.; Stevenson, Mario; Latz, Eicke

2012-01-01

360

Mitochondrial function and increased convective O2 transport: implications for the assessment of mitochondrial respiration in vivo.  

PubMed

Although phosphorus magnetic resonance spectroscopy ((31)P-MRS)-based evidence suggests that in vivo peak mitochondrial respiration rate in young untrained adults is limited by the intrinsic mitochondrial capacity of ATP synthesis, it remains unknown whether a large, locally targeted increase in convective O2 delivery would alter this interpretation. Consequently, we examined the effect of superimposing reactive hyperemia (RH), induced by a period of brief ischemia during the last minute of exercise, on oxygen delivery and mitochondrial function in the calf muscle of nine young adults compared with free-flow conditions (FF). To this aim, we used an integrative experimental approach combining (31)P-MRS, Doppler ultrasound imaging, and near-infrared spectroscopy. Limb blood flow [area under the curve (AUC), 1.4 ± 0.8 liters in FF and 2.5 ± 0.3 liters in RH, P < 0.01] and convective O2 delivery (AUC, 0.30 ± 0.16 liters in FF and 0.54 ± 0.05 liters in RH, P < 0.01), were significantly increased in RH compared with FF. RH was also associated with significantly higher capillary blood flow (P < 0.05) and faster tissue reoxygenation mean response times (70 ± 15 s in FF and 24 ± 15 s in RH, P < 0.05). This resulted in a 43% increase in estimated peak mitochondrial ATP synthesis rate (29 ± 13 mM/min in FF and 41 ± 14 mM/min in RH, P < 0.05) whereas the phosphocreatine (PCr) recovery time constant in RH was not significantly different (P = 0.22). This comprehensive assessment of local skeletal muscle O2 availability and utilization in untrained subjects reveals that mitochondrial function, assessed in vivo by (31)P-MRS, is limited by convective O2 delivery rather than an intrinsic mitochondrial limitation. PMID:23813526

Layec, Gwenael; Haseler, Luke J; Trinity, Joel D; Hart, Corey R; Liu, Xin; Le Fur, Yann; Jeong, Eun-Kee; Richardson, Russell S

2013-06-27

361

Combined chelation of bi-functional bis-hydroxypiridinone and mono-hydroxypiridinone: synthesis, solution and in vivo evaluation.  

PubMed

3-Hydroxy-4-pyridinones (3,4-HP) are well known iron-chelators with applications in medicinal chemistry, mainly associated with their high affinity towards trivalent hard metal ions (e.g. M(3+), M=Fe, Al, Ga) and use as decorporating agents in situations of metal accumulation. The polydenticity and the extra-functionality of 3,4-HP derivatives have been explored, aimed at improving the chelating efficacy and the selectivity of the interaction with specific biological receptors. However, the ideal conjugation of both features in one molecular unity usually leads to high molecular weight compounds which can have crossing-membrane limitations. Herein, a different approach is used combining a arylpiperazine-containing bis-hydroxypyridone (H(2)L(1)) with a biomimetic mono-hydroxypyridinone, ornithine-derivative (HL(2)), to assess the potential coadjuvating effect that could result from the administration of both compounds for the decorporation of hard metal ions. This work reports the results of solution and in vivo studies on their chelating efficacy either as a simple binary or a ternary system (H(2)L(1):HL(2):M(3+)), using potentiometric and spectrophotometric methods. The solution complexation studies with Fe(III) indicate that the solubility of the complexes is considerably increased in the ternary system, an important feature for the metal complex excretion, upon the metal sequestration. The results of the in vivo studies with (67)Ga-injected mice show differences on the biodistribution profiles of the radiotracer, upon the administration of each chelating agent, that are mainly ascribed to the differences of their extra-functional groups and lipo/hydrophilic character. However, administration of both chelating agents leads to a more steady metal mobilization, which may be attributed to an improved access to different cellular compartments. PMID:19091421

Gama, Sofia; Gil, Marco; Gano, Lurdes; Farkas, Etelka; Amélia Santos, M

2008-11-07

362

Functional Stability (at +4°C) of hematopoietic stem and progenitor cells amplified ex vivo from cord blood CD34+ Cells.  

PubMed

Our previously published ex vivo expansion procedure starting from cord blood CD34+ cells enables a massive expansion of total and CD34+ cells and committed progenitors without negative impact on stem cells exhibiting both short- and long-term repopulating capacity. It was upgraded to clinical scale [Macopharma HP01(®) medium in presence of SCF, FLT3-L (100 ng/ml each), G-SCF (10 ng/ml), and TPO (20 ng/ml)] and is in use for an ongoing clinical trial (adult allogeneic context), yielding encouraging results. In order to test the possibility to use the expanded cells in distant transplantation centers, we studied the functional stability at +4°C (usual temperature of transportation) of hematopoietic progenitors and stem cells 48 h after expansion. If the cells were washed and resuspended in 4% albumin solution (actual procedure for immediate injection), only one half of total nucleated and CD34+ cells and 30% of committed progenitors survived after 24 h. This condition has also an evident negative impact on stem cells in expansion product as demonstrated on the basis of reconstitution of NSG mice bone marrow by human CD45, CD33, CD19+ cells as well as by human committed progenitors (CFU). Surprisingly, if the cells were stored 48 h at +4°C in culture medium, very good survival of total and CD34+ cells (90 to 100%) and colony forming unit cells (CFCs; around 70%) was obtained, as well as the maintenance of stem cells (the same in vivo assay with NSG mice). These data point to the possibility of the maintenance of the full functional capacity of expanded grafts for 2 days, the time allowing for its transportation to any transplantation center worldwide. PMID:23044189

Duchez, Pascale; Chevaleyre, Jean; Brunet de la Grange, Philippe; Vlaski, Marija; Boiron, Jean-Michel; Ivanovic, Zoran

2012-10-04

363

Assessing mucin expression and function in human ocular surface epithelia in vivo and in vitro.  

PubMed

Mucins of the corneal and conjunctival epithelia are necessary for the protection of the ocular surface against desiccation, pathogen access, and injury. Detection and quantification of mucins is important for the understanding of ocular surface diseases that cause impaired vision and, in advanced stages, blindness. Advances in the field of molecular biology have made it possible to study membrane mucins and their associated O-glycans in established cell culture models of human ocular surface epithelia. This chapter discusses procedures to detect and quantify mucin RNA and protein in biological samples, as well as methods to experimentally manipulate the epithelia in culture by shRNA, to understand the function of specific mucins. Example protocols are provided to evaluate the role of ocular surface mucins in mucosal barrier function and bacteria-host interactions. PMID:22259145

Argüeso, Pablo; Gipson, Ilene K

2012-01-01

364

Assessing Mucin Expression and Function in Human Ocular Surface Epithelia in vivo and in vitro  

PubMed Central

Mucins of the corneal and conjunctival epithelia are necessary for the protection of the ocular surface against desiccation, pathogen access, and injury. Detection and quantification of mucins is important for the understanding of ocular surface diseases that cause impaired vision and, in advanced stages, blindness. Advances in the field of molecular biology have made possible to study membrane mucins and their associated O-glycans in established cell culture models of human ocular surface epithelia. This chapter discusses procedures to detect and quantify mucin RNA and protein in biological samples, as well as methods to experimentally manipulate the epithelia in culture by shRNA, to understand the function of specific mucins. Example protocols are provided to evaluate the role of ocular surface mucins in mucosal barrier function and bacteria-host interactions.

Argueso, Pablo; Gipson, Ilene K.

2012-01-01

365

In vivo DNA expression of functional brome mosaic virus RNA replicons in Saccharomyces cerevisiae.  

PubMed Central

To facilitate manipulation of brome mosaic virus (BMV) RNA replicons in Saccharomyces cerevisiae and for yeast genetic analysis of BMV RNA replication, gene expression, and host interactions, we constructed DNA plasmids from which BMV RNA3 and RNA3 derivatives can be transcribed in vivo from the galactose-inducible yeast GAL1 promoter and terminated by a self-cleaving ribozyme at or near their natural 3' ends. In galactose-induced yeast harboring such plasmids, expression of BMV RNA replication proteins 1a and 2a led to synthesis of negative-strand RNA3, amplification of positive-strand RNA3 to levels over 45-fold higher than those of DNA-derived RNA3 transcripts, and synthesis of the RNA3-encoded subgenomic mRNA for coat protein. Although the GAL1 promoter initiated transcription from multiple sites, 1a and 2a selectively amplified RNA3 with the authentic viral 5' end. As expected, reporter genes substituted for the 3'-proximal coat protein gene could not be translated directly from DNA-derived RNA3 transcripts, so their expression depended on 1a- and 2a-directed subgenomic mRNA synthesis. In yeast in which DNA transcription of B3CAT, an RNA3 derivative with the chloramphenicol acetyltransferase (CAT) gene replacing the coat gene, was induced, CAT activity remained near background levels in the absence of 1a and 2a but increased over 500,000-fold when 1a and 2a were expressed. Similarly, a plasmid encoding B3URA3, an RNA3 derivative with the yeast URA3 gene replacing the coat gene, conferred uracil-independent growth to ura3- yeast only after 1a and 2a expression and galactose induction. Once its 1a- and 2a-dependent replication was initiated, B3URA3 was maintained in dividing yeast as a free RNA replicon, even after repression of the GAL1 promoter or the loss of the B3URA3 cDNA plasmid. These findings should be useful for many experimental purposes.

Ishikawa, M; Janda, M; Krol, M A; Ahlquist, P

1997-01-01

366

Oocyte-specific knockout: a novel in vivo approach for studying gene functions during folliculogenesis, oocyte maturation, fertilization, and embryogenesis.  

PubMed

Knockout mice have been highly useful tools in helping to understand the functional roles of specific genes in development and diseases. However, in many cases, knockout mice are embryonic lethal, which prevents investigation into a number of important questions, or they display developmental abnormalities, including fertility defects. In contrast, conditional knockout, which is achieved by the Cre-LoxP system, can be used to delete a gene in a specific organ or tissue, or at a specific developmental stage. This technique has advantages over conventional knockout, especially when conventional knockout causes embryonic lethality or when the function of maternal transcripts in early development needs to be defined. Recently, a widely used practice has been used to specifically delete genes of interest in oocytes: Zp3-Cre or Gdf9-Cre transgenic mouse lines, in which Cre-recombinase expression is driven by oocyte-specific zona pellucida 3 (Zp3) promoter or growth differentiation factor 9 (Gdf9) promoter, are crossed with mice bearing floxed target genes. This novel in vivo approach has helped to increase the understanding of the functions of specific genes in folliculogenesis/oogenesis, oocyte maturation, fertilization, and embryogenesis. In this minireview we discuss recent advances in understanding the molecular mechanisms regulating major reproductive and developmental events as revealed by oocyte-specific conditional knockout and perspectives on this technology and related studies. PMID:18753607

Sun, Qing-Yuan; Liu, Kui; Kikuchi, Kazuhiro

2008-08-27

367

Combined functional MRI and tractography to demonstrate the connectivity of the human primary motor cortex in vivo.  

PubMed

In this study, we combined advanced MR techniques to explore primary motor cortex (M1) connectivity in the human brain. We matched functional and anatomical information using motor functional MRI (fMRI) and white matter tractography inferred from diffusion tensor imaging (DTI). We performed coregistered DTI and motor task fMRI in 8 right-handed healthy subjects and in 1 right-handed patient presenting with a left precentral tumour. We used the fast-marching tractography (FMT) algorithm to define 3D connectivity maps within the whole brain, from seed points selected in the white matter adjacent to the location of the maximum of fMRI activation. Connectivity maps were then anatomically normalised and analysed using statistical parametric mapping software (SPM99) allowing group comparisons (left versus right hemisphere in control subjects and patient versus control subjects). The results demonstrated, in all control subjects, strong connections from M1 to the pyramidal tracts, premotor areas, parietal cortices, thalamus, and cerebellum. M1 connectivity was asymmetric, being more extensive in the dominant hemisphere. The patient had differences in M1 connectivity from the control group. Thus, fMRI-correlated DTI-FMT is a promising tool to study the structural basis of functional networks in the human brain in vivo. PMID:12948693

Guye, Maxime; Parker, Geoffrey J M; Symms, Mark; Boulby, Philip; Wheeler-Kingshott, Claudia A M; Salek-Haddadi, Afraim; Barker, Gareth J; Duncan, John S

2003-08-01

368

The variation of function across the human insula mirrors its patterns of structural connectivity: evidence from in vivo probabilistic tractography.  

PubMed

The human insula is a functionally complex yet poorly understood region of the cortex, implicated in a wide range of cognitive, motor, emotion and somatosensory activity. To elucidate the functional role of the insula, the current study used in vivo probabilistic tractography to map the structural connectivity of seven anatomically-defined insular subregions. The connectivity patterns identified reveal two complementary insular networks connected via a dual route architecture, and provide key insights about the neural basis of the numerous functions ascribed to this area. Specifically, anterior-most insular regions were associated with a ventrally-based network involving orbital/inferior frontal and anterior/polar temporal regions, forming part of a key emotional salience and cognitive control network associated with the implementation of goal-directed behavior. The posterior and dorsal-middle insular regions were associated with a network focused on posterior and (to a lesser extent) anterior temporal regions via both dorsal and ventral pathways. This is consistent with the involvement of the insula in sound-to-speech transformations, with an implicated role in the temporal resolution, sequencing, and feedback processes crucial for auditory and motor processing, and the monitoring and adjustment of expressive performance. PMID:22100771

Cloutman, Lauren L; Binney, Richard J; Drakesmith, Mark; Parker, Geoffrey J M; Lambon Ralph, Matthew A

2011-11-13

369

Ex vivo cultures of microglia from young and aged rodent brain reveal age-related changes in microglial function.  

PubMed

To understand how microglial cell function may change with aging, various protocols have been developed to isolate microglia from the young and aged central nervous system (CNS). Here we report modification of an existing protocol that is marked by less debris contamination and improved yields and demonstrate that microglial functions are varied and dependent on age. Specifically, we found that microglia from aged mice constitutively secrete greater amounts of interleukin-6 (IL-6) and tumor necrosis factor-? (TNF-?) relative to microglia from younger mice and are less responsive to stimulation. Also, microglia from aged mice have reduced glutathione levels and internalize less amyloid beta peptide (A?) while microglia from mice of all ages do not retain the amyloid beta peptide for a significant length of time. These studies offer further support for the idea that microglial cell function changes with aging. They suggest that microglial A? phagocytosis results in A? redistribution rather than biophysical degradation in vivo and thereby provide mechanistic insight to the lack of amyloid burden elimination by parenchymal microglia in aged adults and those suffering from Alzheimer's disease. PMID:20580465

Njie, Emalick G; Boelen, Ellen; Stassen, Frank R; Steinbusch, Harry W M; Borchelt, David R; Streit, Wolfgang J

2010-07-02

370

Regulation of cytoplasmic dynein function in vivo by the Drosophila Glued complex  

PubMed Central

The Drosophila Glued gene product shares sequence homology with the p150 component of vertebrate dynactin. Dynactin is a multiprotein complex that stimulates cytoplasmic dynein-mediated vesicle motility in vitro. In this report, we present biochemical, cytological, and genetic evidence that demonstrates a functional similarity between the Drosophila Glued complex and vertebrate dynactin. We show that, similar to the vertebrate homologues in dynactin, the Glued polypeptides are components of a 20S complex. Our biochemical studies further reveal differential expression of the Glued polypeptides, all of which copurify as microtubule-associated proteins. In our analysis of the Glued polypeptides encoded by the dominant mutation, Glued, we identify a truncated polypeptide that fails to assemble into the wild-type 20S complex, but retains the ability to copurify with microtubules. The spatial and temporal distribution of the Glued complex during oogenesis is shown by immunocytochemistry methods to be identical to the pattern previously described for cytoplasmic dynein. Significantly, the pattern of Glued distribution in oogenesis is dependent on dynein function, as well as several other gene products known to be required for proper dynein localization. In genetic complementation studies, we find that certain mutations in the cytoplasmic dynein heavy chain gene Dhc64C act as dominant suppressors or enhancers of the rough eye phenotype of the dominant Glued mutation. Furthermore, we show that a mutation that was previously isolated as a suppressor of the Glued mutation is an allele of Dhc64C. Together with the observed dependency of Glued localization on dynein function, these genetic interactions demonstrate a functional association between the Drosophila dynein motor and Glued complexes.

1995-01-01

371

The functional response of upstream DNA to dynamic supercoiling in vivo  

Microsoft Academic Search

Because RNA polymerase is a powerful motor, transmission of transcription-generated forces might directly alter DNA structure, chromatin or gene activity in mammalian cells. Here we show that transcription-generated supercoils streaming dynamically from active promoters have considerable consequences for DNA structure and function in cells. Using a tamoxifen-activatable Cre recombinase to excise a test segment of chromatin positioned between divergently transcribed

Fedor Kouzine; Suzanne Sanford; Zichrini Elisha-Feil; David Levens

2008-01-01

372

In Vivo Function of Hsp90 Is Dependent on ATP Binding and ATP Hydrolysis  

Microsoft Academic Search

Heat shock protein 90 (Hsp90), an abundant molecular chaperone in the eukaryotic cytosol, is in- volved in the folding of a set of cell regulatory proteins and in the re-folding of stress-denatured polypeptides. The basic mechanism of action of Hsp90 is not yet un- derstood. In particular, it has been debated whether Hsp90 function is ATP dependent. A recent crystal

Wolfgang M. J. Obermann; Holger Sondermann; Alicia A. Russo; Nikola P. Pavletich; F. Ulrich Hartl

1998-01-01

373

Geometric modeling, functional parameter calculation, and visualization of the in-vivo distended rectal wall  

NASA Astrophysics Data System (ADS)

The rectum can distend to accommodate stool, and contracts in response to distention during defecation. Rectal motor dysfunctions are implicated in the pathophysiology of functional defecation disorders and fecal incontinence. These rectal motor functions can be studied by intra-luminal measurements of pressure by manometry, or combined with volume during rectal balloon distention. Pressure-volume (p-v) relationships provide a global index of rectal mechanical properties. However, balloon distention alone does not measure luminal radius or wall thickness, which are necessary to compute wall tension and stress respectively. It has been suggested that the elastic modulus, which is the linear slope of the stress-strain relationship, is a more accurate measure of wall stiffness. Also, measurements of compliance may not reflect differences in rectal diameter between subjects prior to inflation, and imaging is necessary to determine if, as has been suggested, rectal pressure-volume relationships are affected by extra-rectal structures. We have developed a technique to measure rectal stress:strain relationships in humans, by simultaneous magnetic resonance imaging (MRI) during rectal balloon distention. After a conditioning distention, a rectal balloon was distended with water from 0 to 400 ml in 50 ml steps, and imaged at each step with MRI. The fluid filled balloon was segmented from each volume, the phase-ordered binary volumes were transformed into a geometric characterization of the inflated rectal surface. Taken together with measurements of balloon pressure and of rectal wall thickness, this model of the rectal surface was used to calculate regional values of curvature, tension, strain, and stress for the rectum. In summary, this technique has the unique ability to non-invasively measure the rectal stress:strain relationship and also determine if rectal expansion is limited by extra-rectal structures. This functional information allows the direct clinical analysis of rectal motor function and offers the potential for characterizing abnormal mechanical properties of the rectal wall in disease.

Haider, Clifton R.; Manduca, Armando; Camp, Jon J.; Fletcher, Joel G.; Robb, Richard A.; Bharucha, Adil E.

2006-03-01

374

FAM20C functions intracellularly within both ameloblasts and odontoblasts in vivo.  

PubMed

FAM20C, also known as Golgi Casein Kinase (G-CK), is proposed to be the archetype for a family of secreted kinases that phosphorylate target proteins in the Golgi and in extracellular matrices, but FAM20C serving an extracellular function is controversial. FAM20C phosphorylates secretory calcium-binding phosphoproteins (SCPPs), which are associated with the evolution of biomineralization in vertebrates. Current models of biomineralization assume SCPP proteins are secreted as phosphoproteins and their phosphates are essential for protein conformation and function. It would be a radical departure from current theories if proteins in mineralizing matrices were dephosphorylated as part of the mineralization mechanism and rephosphorylated in the extracellular milieu by FAM20C using ATP. To see if such mechanisms are possible in the formation of dental enamel, we tested the hypothesis that FAM20C is secreted by ameloblasts and accumulates in the enamel extracellular matrix during tooth development. FAM20C localization was determined by immunohistochemistry in Day 5 mouse incisors and molars and by Western blot analyses of proteins extracted from pig enamel organ epithelia (EOE) and enamel shavings. FAM20C localized intracellularly within ameloblasts and odontoblasts in a pattern consistent with Golgi localization. Western blots detected FAM20C in the EOE extracts but not in the enamel matrix. We conclude that FAM20C is not a constituent of the enamel extracellular matrix and functions intracellularly within ameloblasts. PMID:23703840

Wang, Shih-Kai; Samann, Andrew C; Hu, Jan C-C; Simmer, James P

2013-05-23

375

Functional comparison of Deinococcus radiodurans Dps proteins suggests distinct in vivo roles.  

PubMed

Deinococcus radiodurans exhibits extreme resistance to DNA damage and is one of only few bacteria that encode two Dps (DNA protection during starvation) proteins. Dps-1 was shown previously to bind DNA with high affinity and to localize to the D. radiodurans nucleoid. A unique feature of Dps-2 is its predicted signal peptide. In the present paper, we report that Dps-2 assembly into a dodecamer requires the C-terminal extension and, whereas Dps-2 binds DNA with low affinity, it protects against degradation by reactive oxygen species. Consistent with a role for Dps-2 in oxidative stress responses, the Dps-2 promoter is up-regulated by oxidative stress, whereas the Dps-1 promoter is not. Although DAPI (4',6-diamidino-2-phenylindole) staining of Escherichia coli nucleoids shows that Dps-1 can compact genomic DNA, such nucleoid condensation is absent from cells expressing Dps-2. A fusion of EGFP (enhanced green fluorescent protein) to the Dps-2 signal peptide results in green fluorescence at the perimeter of D. radiodurans cells. The differential response of the Dps-1 and Dps-2 promoters to oxidative stress, the distinct cellular localization of the proteins and the differential ability of Dps-1 and Dps-2 to attenuate hydroxyl radical production suggest distinct functional roles; whereas Dps-1 may function in DNA metabolism, Dps-2 may protect against exogenously derived reactive oxygen species. PMID:22857940

Reon, Brian J; Nguyen, Khoa H; Bhattacharyya, Gargi; Grove, Anne

2012-11-01

376

Nuclear magnetic resonance spectroscopy: biochemical evaluation of brain function in vivo and in vitro.  

PubMed

Nuclear magnetic resonance spectroscopy (MRS) offers a unique opportunity to monitor mmolar concentrations of high energy phosphates, glucose, lactate and amino acids. The possibility of obtaining information about chemical constituents noninvasively is of great importance. MRS and chemical shift imaging (CSI) are emerging as tools for tumor grading, monitoring of treatment, ischemia research, in pediatric research for follow-up of children with borderline mental retardation, for defining brain death and to define epileptic foci. It is important to know which cell type (neuronal or glial) shows changes as a result of external manipulations (e.g. excitotoxins) or internal changes (brain pathology). Metabolic studies have been carried out on brain cell cultures. By using 13C labeled glucose and acetate in combination with 13C MRS it was shown that astrocytes release lactate, glutamine, citrate and alanine and that cerebral cortical neurons use glutamine released from astrocytes as a precursor for GABA synthesis. An important feature in MRS is the localization of N-acetyl aspartate in neurons, since this enables monitoring of neuronal reactions, such as survival after neurotoxic insults. Recent advances have yielded high speed functional echo planar imaging (EPI) techniques that are sensitive to changes in cerebral blood volume, blood flow and blood oxygenation (Functional MRI). During cognitive task performance, local alterations in neuronal activity induce local changes in cerebral metabolism and cerebral perfusion, which can now be detected with MRI. PMID:7854591

Sonnewald, U; Gribbestad, I S; Westergaard, N; Nilsen, G; Unsgård, G; Schousboe, A; Petersen, S B

1994-01-01

377

A USPL functional system with articulated mirror arm for in-vivo applications in dentistry  

NASA Astrophysics Data System (ADS)

Ultra-short pulsed laser (USPL) systems for dental application have overcome many of their initial disadvantages. However, a problem that has not yet been addressed and solved is the beam delivery into the oral cavity. The functional system that is introduced in this study includes an articulated mirror arm, a scanning system as well as a handpiece, allowing for freehand preparations with ultra-short laser pulses. As laser source an Nd:YVO4 laser is employed, emitting pulses with a duration of tp < 10 ps at a repetition rate of up to 500 kHz. The centre wavelength is at 1064 nm and the average output power can be tuned up to 9 W. The delivery system consists of an articulated mirror arm, to which a scanning system and a custom made handpiece are connected, including a 75 mm focussing lens. The whole functional system is compact in size and moveable. General characteristics like optical losses and ablation rate are determined and compared to results employing a fixed setup on an optical table. Furthermore classical treatment procedures like cavity preparation are being demonstrated on mammoth ivory. This study indicates that freehand preparation employing an USPL system is possible but challenging, and accompanied by a variety of side-effects. The ablation rate with fixed handpiece is about 10 mm3/min. Factors like defocussing and blinding affect treatment efficiency. Laser sources with higher average output powers might be needed in order to reach sufficient preparation speeds.

Schelle, Florian; Meister, Jörg; Dehn, Claudia; Oehme, Bernd; Bourauel, Christoph; Frentzen, Mathias

378

Transcranial imaging of functional cerebral hemodynamic changes in single blood vessels using in vivo photoacoustic microscopy.  

PubMed

Optical imaging of changes in total hemoglobin concentration (HbT), cerebral blood volume (CBV), and hemoglobin oxygen saturation (SO(2)) provides a means to investigate brain hemodynamic regulation. However, high-resolution transcranial imaging remains challenging. In this study, we applied a novel functional photoacoustic microscopy technique to probe the responses of single cortical vessels to left forepaw electrical stimulation in mice with intact skulls. Functional changes in HbT, CBV, and SO(2) in the superior sagittal sinus and different-sized arterioles from the anterior cerebral artery system were bilaterally imaged with unambiguous 36 × 65-?m(2) spatial resolution. In addition, an early decrease of SO(2) in single blood vessels during activation (i.e., 'the initial dip') was observed. Our results indicate that the initial dip occurred specifically in small arterioles of activated regions but not in large veins. This technique complements other existing imaging approaches for the investigation of the hemodynamic responses in single cerebral blood vessels. PMID:22472612

Liao, Lun-De; Lin, Chin-Teng; Shih, Yen-Yu I; Duong, Timothy Q; Lai, Hsin-Yi; Wang, Po-Hsun; Wu, Robby; Tsang, Siny; Chang, Jyh-Yeong; Li, Meng-Lin; Chen, You-Yin

2012-04-04

379

Transcranial imaging of functional cerebral hemodynamic changes in single blood vessels using in vivo photoacoustic microscopy  

PubMed Central

Optical imaging of changes in total hemoglobin concentration (HbT), cerebral blood volume (CBV), and hemoglobin oxygen saturation (SO2) provides a means to investigate brain hemodynamic regulation. However, high-resolution transcranial imaging remains challenging. In this study, we applied a novel functional photoacoustic microscopy technique to probe the responses of single cortical vessels to left forepaw electrical stimulation in mice with intact skulls. Functional changes in HbT, CBV, and SO2 in the superior sagittal sinus and different-sized arterioles from the anterior cerebral artery system were bilaterally imaged with unambiguous 36 × 65-?m2 spatial resolution. In addition, an early decrease of SO2 in single blood vessels during activation (i.e., ‘the initial dip') was observed. Our results indicate that the initial dip occurred specifically in small arterioles of activated regions but not in large veins. This technique complements other existing imaging approaches for the investigation of the hemodynamic responses in single cerebral blood vessels.

Liao, Lun-De; Lin, Chin-Teng; Shih, Yen-Yu I; Duong, Timothy Q; Lai, Hsin-Yi; Wang, Po-Hsun; Wu, Robby; Tsang, Siny; Chang, Jyh-Yeong; Li, Meng-Lin; Chen, You-Yin

2012-01-01

380

In vivo and in vitro analyses of a Bombyx mori nucleopolyhedrovirus mutant lacking functional vfgf.  

PubMed

All lepidopteran baculovirus genomes sequenced to date encode a viral fibroblast growth factor homolog (vfgf), suggesting that vfgf may play an important role in the infection cycle of lepidopteran baculoviruses. Here, we describe the characterization of a Bombyx mori nucleopolyhedrovirus (BmNPV) mutant lacking functional vfgf. We constructed a vfgf deletion mutant (BmFGFD) and characterized it in BmN cells and B. mori larvae. We observed that budded virus (BV) production was reduced in BmFGFD-infected BmN cells and B. mori larvae. The larval bioassays also revealed that deletion of vfgf did not reduce the infectivity; however, the mutant virus did take 20 h longer to kill B. mori larvae than wild-type BmNPV, when tested either by BV injection or by polyhedrin-inclusion body ingestion. These results suggest that BmNPV vfgf is involved in efficient virus production in BmN cells and B. mori larvae. PMID:16904150

Katsuma, Susumu; Horie, Satoshi; Daimon, Takaaki; Iwanaga, Masashi; Shimada, Toru

2006-08-09