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91.
92.
Leticia Morales-Ledesma Rosa Linares Gabriela Rosas Carolina Morán Roberto Chavira Mario Cárdenas Roberto Domínguez 《Reproductive biology and endocrinology : RB&E》2010,8(1):99
The present study tested the hypothesis that if polycystic ovary syndrome (PCOS) results from activating the noradrenergic
outflow to the ovary, unilaterally sectioning the superior ovarian nerve (SON) will result in ovulation by the denervated
ovary, and the restoration of progesterone (P4), testosterone (T) and estradiol (E2) normal serum level. A single 2 mg dose
of estradiol valerate (EV) to adult rats results in the development of a syndrome similar to the human PCOS. Ten-day old rats
were injected with EV or vehicle solution (Vh) and were submitted to sham surgery, unilateral or bilateral sectioning of the
SON at 24-days of age. The animals were sacrificed at 90 to 92 days of age, when they presented vaginal estrus preceded by
a pro-estrus smear. In EV-treated animals, unilateral sectioning of the SON restored ovulation by the innervated ovary and
unilateral or bilateral sectioning of the SON normalized testosterone and estradiol levels. These results suggest that aside
from an increase in ovarian noradrenergic tone in the ovaries, in the pathogenesis of the PCOS participate other neural influences
arriving to the ovaries via the SON, regulating spontaneous ovulation. Changes in P4, T and E2 serum levels induced by EV
treatment seem to be controlled by neural signals arising from the abdominal wall and other signals arriving to the ovaries
through the SON, and presents asymmetry. 相似文献
93.
Rodrigo de Cássio da Silva Rafael Rosas Oliveira Sandra Maria Feliciano de Oliveira Azevedo Raquel Moares Soares Valéria Freitas De Magalhães 《Journal of fish biology》2021,99(4):1274-1279
Cylindrospermopsin (CYN) is a cyanotoxin that has raised serious concerns about public health in many parts of the world. It can bioaccumulate and affect the health of aquatic organisms, but despite this, few studies have been conducted on CYN uptake and clearance in fish. In this paper, the authors evaluate the uptake and clearance of CYN in the muscle tissue and viscera of juvenile tilapia (Oreochromis niloticus) after exposure to aqueous extracts and whole cells of Cylindrospermopsis raciborskii (CYN-producer). CYN blended with commercial fish food, and three experiments were conducted. In the first trial, fish food, and aqueous extracts containing 0.31 μg CYN g−1 of food per day, was administered to tilapia for 15 days. In the second trial, fish were provided food and intact cells (5.4 μg CYN g−1 of food per day) for 15 days. In the last trial, they were provided fish food and aqueous extracts (0.8 μg CYN g−1 of food per day) for 12 days, and for the next 10 days, the animals were fed food without toxic cell extracts (to simulate a clearance period). The concentration of CYN in muscle tissue and viscera was analysed using ELISA. In the case of juvenile tilapia, the presence of CYN was higher in viscera than in muscle tissue, and the toxin remained in the tissues even after 10 days without the addition of contaminated food. The results suggest that tilapia represents a potential source of CYN transfer through the food web, and this shows the need for a continuous monitoring of this compound in organisms that are used for human and animal consumption. 相似文献
94.
Growth hormone restores aged diaphragm myosin composition and performance after chronic undernutrition. 总被引:2,自引:0,他引:2
B T Ameredes J F Watchko M J Daood J F Rosas M P Donahoe R M Rogers 《Journal of applied physiology》1999,87(4):1253-1259
The effects of growth hormone (GH) on diaphragm muscle myosin heavy chain (MHC) composition and mechanical performance were investigated in Fischer 344 male rats aged to senescence (24.5 mo of age). Chronic undernutrition (UN), refeeding (RF), and RF+GH were compared with ad libitum feeding by using a model of UN that produced a 50% decrease in body weight over a 12-mo period. The effect of aging was assessed by comparing MHC composition of ad libitum-fed rats at 12 and 24.5 mo of age. At senescence, significant decreases in slow type I (-23%) and fast type IIA (-31%) MHC had occurred with aging. Conversely, UN over this aging period increased types I (32-73%) and IIA (22-23%) MHC and decreased fast types IIB (32-54%) and IIX (30-31%) MHC. RF and RF+GH reversed these shifts back toward control values. At senescence, maximal specific force, maximal velocity, and specific power capacity were not different across treatment groups. During repetitive isotonic contraction trials, the diaphragms of UN rats maintained power production over time (54% of initial power at 60 s), whereas the power production of diaphragms of ad libitum-fed rats fell to 0% (P < 0.05). In comparison with UN rats, the diaphragms of RF and RF+GH rats produced 23 (not significant) and 11% (P < 0.05) of initial power, respectively, suggesting that RF+GH treatment restored performance characteristics after UN. We conclude that RF+GH can reverse alterations in MHC composition and mechanical performance produced by chronic UN in the aged rat diaphragm. 相似文献
95.
M E Rodriguez Rosas A Shibukawa Y Yoshikawa Y Kuroda T Nakagawa 《Analytical biochemistry》1999,274(1):27-33
High-performance frontal analysis (HPFA) was used to investigate the binding properties of human alpha(1)-acid glycoprotein (AGP) with semotiadil ((R)-isomer, Ca-channel blocker) and its antipode levosemotiadil ((S)-isomer, Ca- and Na-channel blockers). An on-line HPLC system consisting of a HPFA column, an extraction column, and an analytical HPLC column was used to determine the unbound concentrations of these enantiomers, and the experimental data were subsequently subjected to the Scatchard analyses to estimate their binding parameters. The binding affinity of the (R)-isomer (K = 3.17 x 10(7) M, n = 0.74) is approximately 1.2 times stronger than that of (S)-isomer (K = 2.59 x 10(7) M, n = 0.74). An enantioselective competitive binding study indicated that both enantiomers are bound at the same site on AGP molecules. 相似文献
96.
The mandibular specimens AT-250 and AT-793 (individual IV) and AT-888 (individual XXI) from the Atapuerca Middle Pleistocene
sample show a combination of traits interpreted as evidence of senescence. In order to explore age-related mandibular changes
relevant to the interpretation of the Atapuerca hominids, the sample of known age and sex from Spitalfields (London) and the
Neolithic sample from Abu Hureyra (Syria) were used as a baseline. Results obtained indicate that the occurrence of an enlarged
and posteriorly located mental foramen, in association with high alveolar resorption in AT-250 and AT-888, support the hypothesis
of senescence in individuals IV and XXI from the Atapuerca sample. The findings suggest that European Middle Pleistocene populations
lived long enough to reach senescence. The age at death for Middle Pleistocene hominids and Neanderthals has previously been
estimated at around 40–45 years in the oldest specimens. The appearance of senescence processes before this age is indicative
of higher rates of morphological aging in the clade which gave rise to Neanderthals. The anatomical significance of ageing
features when considered in the context of craniofacial remodelling can help in the understanding of the taxonomic status
of these morphological traits. 相似文献
97.
Melanin and virulence in Cryptococcus neoformans 总被引:2,自引:0,他引:2
Melanin synthesis has been associated with virulence for the human pathogenic fungus Cryptococcus neoformans. Recent evidence indicates that C. neoformans cells synthesize melanin during infection and that this pigment protects the fungus against immune defense mechanisms. 相似文献
98.
Claire J Greenhill Gareth W Jones Mari A Nowell Zarabeth Newton Ann K Harvey Abdul N Moideen Fraser L Collins Anja C Bloom Rebecca C Coll Avril AB Robertson Matthew A Cooper Marcela Rosas Philip R Taylor Luke A O’Neill Ian R Humphreys Anwen S Williams Simon A Jones 《Arthritis research & therapy》2014,16(4)
Introduction
Activation of the inflammasome has been implicated in the pathology of various autoinflammatory and autoimmune diseases. While the NLRP3 inflammasome has been linked to arthritis progression, little is known about its synovial regulation or contribution to joint histopathology. Regulators of inflammation activation, such as interleukin (IL)-10, may have the potential to limit the inflammasome-driven arthritic disease course and associated structural damage. Hence, we used IL-10-deficient (IL-10KO) mice to assess NLRP3 inflammasome-driven arthritic pathology.Methods
Antigen-induced arthritis (AIA) was established in IL-10KO mice and wild-type controls. Using histological and radiographic approaches together with quantitative real-time PCR of synovial mRNA studies, we explored the regulation of inflammasome components. These were combined with selective blocking agents and ex vivo investigative studies in osteoclast differentiation assays.Results
In AIA, IL-10KO mice display severe disease with increased histological and radiographic joint scores. Here, focal bone erosions were associated with increased tartrate-resistant acid phosphatase (TRAP)-positive cells and a localized expression of IL-1β. When compared to controls, IL-10KO synovium showed increased expression of Il1b, Il33 and NLRP3 inflammasome components. Synovial Nlrp3 and Casp1 expression further correlated with Acp5 (encoding TRAP), while neutralization of IL-10 receptor signaling in control mice caused increased expression of Nlrp3 and Casp1. In ex vivo osteoclast differentiation assays, addition of exogenous IL-10 or selective blockade of the NLRP3 inflammasome inhibited osteoclastogenesis.Conclusions
These data provide a link between IL-10, synovial regulation of the NLRP3 inflammasome and the degree of bone erosions observed in inflammatory arthritis.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0419-y) contains supplementary material, which is available to authorized users. 相似文献99.
Alcoholism is a significant public health problem. A picture of the genetic architecture underlying alcohol-related phenotypes
is emerging from genome-wide association studies and work on genetically tractable model organisms. 相似文献
100.