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61.
The effect of sodium selenite (0.05, 0.1, and 0.2 mg/kg body weight, ip) on the contents of lipids (phospholipids, cholesterol, esterified fatty acids, gangliosides), thiobarbituric acid reactive substance (TBARS), and thiol group in circadian rhythm centers (preoptic area, brainstem, and posterior hypothalamus) of male Wistar rats was studied after 7 d of treatment. The content of phospholipids was elevated significantly with a dose of 0.1 mg/kg of selenite in the preoptic area and brainstem, but a 0.2-mg/kg dose has depleted its level significantly in these regions. The alteration of phospholipids in posterior hypothalamus was not significant with three doses of sodium selenite. The level of cholesterol in the preoptic area was inhibited significantly with a dose of 0.05 mg/kg sodium selenite, but its level was elevated significantly with a dose of 0.2 mg/kg selenite in the preoptic area and brainstem. Alteration with three doses of sodium selenite in the posterior hypothalamus was not significant. The ganglioside level in the preoptic area and brainstem was elevated significantly with a 0.1-mg dose of sodium selenite; conversely, a 0.2 mg dose of sodium selenite caused a significant depletion on its content in these areas. In the posterior hypothalamus, the ganglioside level was depleted significantly with a dose of 0.1 mg, but elevated significantly with a dose of 0.2 mg of sodium selenite. The level of esterified fatty acids was decreased significantly in the preoptic area and brainstem with a dose of 0.1 mg/kg sodium selenite, but in these regions, its level was elevated with a dose of 0.2 mg/kg sodium selenite and its elevation was significant in the preoptic area. In the posterior hypothalamus, the alteration of esterified fatty acids with three doses of sodium selenite was not significant. The effect of 0.1 and 0.2 mg/kg sodium selenite on the TBARS level and thiol group in sleep centers was significantly opposite to the wakefulness center. A sodium selenite dose of 0.1 mg/kg had depleted the content of TBARS in the preoptic area and brainstem but elevated the content of the thiol group significantly in the posterior hypothalamus. On the other hand, a 0.2-mg/kg dose of sodium selenite has significantly elevated the content of TBARS but depleted the content of the thiol group significantly in the posterior hypothalamus. No dose-dependent alteration was observed on the content of lipids, TBARS, and thiol group in the circadian rhythm centers of rats.  相似文献   
62.
63.
Gries DA  Condouris GA  Shey Z  Houpt M 《Life sciences》2005,76(15):1667-1674
Few animal studies have explored the interaction of nitrous oxide (N2O) with a benzodiazepine (BNZ) administered by the oral route, as used in clinical procedures involving "conscious sedation". The purpose of this study was to evaluate the relative "anxiolytic-like" and sedative effectiveness of N2O, oral triazolam (TRIAZ; Halcion) or oral diazepam (DIAZ; Valium), either alone or in various combinations of drugs and doses. One hundred and twelve Swiss Webster male mice, 35-45 days old, were assigned to 28 groups, each of which contained four mice. The mouse staircase test was used for the assessment of anxiety (number of rearings) and sedation (number of steps ascended). Three doses of oral TRIAZ (0.1, 0.3, 1.0 mg/kg) or DIAZ (2.0, 3.5, 5.0 mg/kg) were given in combination with room air, or N2O/O2 at a N2O concentration of 25, 50 or 75%. Each mouse was tested once. N2O alone did not reduce NR in any concentration, but caused a significant increase in locomotion. DIAZ without N2O reduced NR only with the middle and high doses, but the addition of N2O significantly enhanced the anxiolytic-like effect of all DIAZ doses. TRIAZ, alone, reduced NR only in the highest dose, but added N2O resulted in anxiolytic-like behavior with all three TRIAZ doses. The sedative effects of the BNZs were extremely variable. Only the middle dose of DIAZ plus 25% N2O unequivocally reduced the number of steps ascended, i.e., caused sedation. TRIAZ lacked the inverted U-shaped dose-response relationship with NR usually seen with DIAZ. TRIAZ, therefore, provides better dose control. This behavioral animal model indicates that the optimal combinations for reduction of anxiety-like behavior with minimal effects on sedation are 0.1 mg/kg oral TRIAZ with 25% N2O or 2.0 mg/kg oral DIAZ with 25% N2O.  相似文献   
64.
Because of its efficacy in inactivating waterborne protozoan cysts and oocysts, ozone is frequently used for disinfection of drinking water. The effect of ozone on cysts of Giardia lamblia was investigated in gerbils (Meriones unguiculatus), using an infectivity assay by scanning electron microscopy, immunoblotting, and flow cytometry. Cysts recovered from experimentally infected gerbils were exposed to an initial ozone concentration of 1.5 mg/L for 0, 30, 60, and 120 sec.This treatment resulted in a dose-dependent reduction in cysts concentration, loss of infectivity in gerbils, and profound structural modifications to the cyst wall. Exposure for 60 sec or longer resulted in extensive protein degradation and in the disappearance of a cyst wall and a trophozoite antigen.  相似文献   
65.
Our recent investigations have postulated a human umbilical vein endothelial cell (HUVEC)-associated prekallikrein activator (PKA). When prekallikrein (PK) assembles on high molecular weight kininogen on HUVEC, PK is activated to kallikrein. PKA was found in the 15,800 x g pellet of HUVEC lysates using an assay that measures PK activation only when bound to high molecular weight kininogen linked to microtiter plates. Sequential DEAE, wheat germ lectin affinity, and hydroxyapatite chromatography resulted in four protein bands on SDS-PAGE. One protein in the 73-kDa band was identified by amino acid sequencing as prolylcarboxypeptidase (PRCP). On gel filtration, PKA activity was a single homogenous peak identical in migration to the 73-kDa immunoblot of PRCP. Anti-PRCP inhibits PKA activity and PK activation on HUVEC. Purified PKA was blocked by diisopropyl fluorophosphate (1 mm), phenylmethylsulfonyl fluoride (3 mm), leupeptin (100 microm), antipain (IC(50) = 2 microm), HgCl(2) (IC(50) = 500 microm), Z-Pro-Pro-aldehyde-dimethyl acetate (IC(50) = 1 microm), and corn trypsin inhibitor (IC(50) = 40 nm). PKA did not correct the coagulant defect in factor XII deficient plasma, was purified from HUVEC cultured in factor XII-deficient serum, was not detected by antibody to factor XII, did not activate FXI, and was not inhibited by a neutralizing antibody to FXII. Angiotensin II (IC(50) = 2 microm) or bradykinin (IC(50) = 100 microm), but not angiotensin II-(1-7) or bradykinin(1-5), and the prolyl oligopeptidase inhibitor Fmoc-Ala-Pyr-CN (IC(50) = 50 nm) also blocked purified PKA activation of PK. The K(m) of PK activation by PRCP is 6.7 nm. PRCP antigen is present on the membrane of fixed but not permeabilized HUVEC. PRCP appears to be a HUVEC-associated PK activator.  相似文献   
66.
Background:Hearing loss due to noise can cause the disturbances toward the quality of life and cause mechanical damage and metabolic decompensation. Distortion Product Otoacoustic Emission (DPOAE) is an examination to assess the sensory function of outer hair cells. Superoxide Dismutase (SOD) and Malondialdehyde (MDA) are markers of oxidative stress. The aim of this study was to identify the correlation between DPOAE examination and SOD and MDA expression in rats exposed to noise.Methods:This research was conducted on 27 rats which were divided into 3 groups, group 1 (control), group 2, and group 3 were groups with 100 dB and 110 dB noise exposure respectively.Results:Our findings show a decrease in SOD expression and DPOAE values as well as an increase in MDA expression in rats exposed to noise and there is a positive correlation between Signal to Noise Ratio (SNR) value with SOD expression (r= 0.733, p= 0.025) and a negative correlation between SNR value with MDA expression (r= -0.678, p= 0.045).Conclusion:our study find the correlation of oxidant and antioxidant status values in the organ of corti and changes in the function of outer hair cells in noise-exposed rat models.Key Words: Malondialdehyde, Noise Induced Hearing Loss, Otoacoustic Emission, Superoxide Dismutase  相似文献   
67.
Saif  Rashid  Henkel  Jan  Mahmood  Tania  Ejaz  Aniqa  Ahmad  Fraz  Zia  Saeeda 《Molecular biology reports》2021,48(11):7273-7280
Background

Natural and artificial selection tend to cause variability that contributes to shape the genome of livestock in a way that differentiates them among the animal kingdom. The particular aim here is to identify positive selection signatures with whole genome pooled-sequence data of Pakistani Teddy goat.

Methods and results

Paired-end alignment of 635,357,043 reads of Teddy goat with (ARS1) reference genome assembly was carried out. Pooled-Heterozygosity (Hp) and Tajima’s D (TD) are applied for validation and getting better hits of selection signals, while pairwise FST statistics is conducted on Teddy vs. Bezoar (wild goat ancestor) for genomic differentiation, moreover annotation of regions under positive selection was also performed. Hp score with???ZHp?>?5 detected six windows having highest hits on Chr. 29, 9, 25, 15 and 14 that harbor HRASLS5, LACE1 and AXIN1 genes which are candidate for embryonic development, lactation and body height. Secondly, ? ZTD value of?>?3.3 showed 4 windows with very strong hits on Chr.5 & 9 which harbor STIM1 and ADM genes related to body mass and weight. Lastly, ? ZFST?<?? 5 generated four strong signals on Chr.5 & 12 harbor LOC102183233 gene. Other significant selection signatures encompass genes associated with wool production, prolificacy and coat colors traits in this breed.

Conclusions

In brief, this study identified the genes under selection in Pakistani Teddy goat that will be helpful to refining the marker-assisted breeding policies and converging required production traits within and across other goat breeds and to explore full genetic potential of this valued species of livestock.

  相似文献   
68.
The present study was conducted to investigate the clinical outcomes of Entamoeba histolytica infection in symptomatic and asymptomatic Orang Asli (aborigine) communities in Malaysia. Examination was performed on 500 stool samples obtained from Orang Asli communities in 3 different states using formalin-ether concentration, trichrome staining, and single-round PCR techniques. Out of 500 stool samples, single infection of E. histolytica, Entamoeba dispar, and Entamoeba moshkovskii was identified in 3.2%, 13.4%, and 1%, respectively. In addition, 10 samples had mixed infections with E. histolytica and E. dispar. Six samples containing E. dispar were also positive for E. moshkovskii, and only 2 samples had E. histolytica in association with E. dispar and E. moshkovskii. Seventeen E. histolytica-positive samples were from symptomatic subjects, whereas the remaining 11 samples came from asymptomatic subjects. These findings suggest a predominant distribution of pathogenic potential of E. histolytica strains in this community. Therefore, further studies on genotyping of E. histolytica is required, to find out association between E. histolytica genotype and the outcome of the infection.  相似文献   
69.
Abstract

Potentially toxic elements and particulate matter (PM) in the ecosystem are regarded as extremely hazardous because of their persistence, toxicity and bioaccumulative characteristics. Therefore, present study was conducted to estimate the ecological and human health risks of potentially toxic elements (Cu, Mn, Pb, Cd and Ni) and particle pollution (TSP, PM10 and PM2.5) at 2 and 60 m roadside distance from 15 different sites at dust polluted megacity of Pakistan. The AQI assessments suggested that the majority of sites were found unhealthy for sensitive at 2 and 60 m roadside distance, which reveals that that quality of road pavement and streets are far below than the required standards resulting huge quantity of dust particles suspended in air by natural and anthropogenic activities. The maximum geo-accumulation index (I geo) values (1.47 and 0.52) and pollution index (PI) values (4.18 and 2.15) were observed for Ni at 2 and 60 m distance away from the muddy edge of the roads. Similarly, maximum contamination factor (CF) values (24.5 and 94.5) and ecological risk index (ERI) values (4.11 and 3.15) were found for Cd at 2 and 60 m. The I geo and PI indicated that the road dust at a distance of 2 m was relatively more contaminated as compared to 60 m roadside distance. Highest cancer risk (CR) values (2.33 adult and 10.9 for children) were observed for Pb at 2 m, while highest CR values (1.21 for adult and 5.67 for children) at 60 m distance. No probable health risk was observed as the total hazard index (HIexp) of all potentially toxic elements was <1. However, children were appeared to be more susceptible to potentially toxic elements. Based on the results, we believe that the exponential increase in traffic load and industries have aggravated the pollution level and it is expected to be increased in the future.  相似文献   
70.
Composition and film quality of perovskite are crucial for the further improvement of perovskite solar cells (PSCs), including efficiency, reproducibility, and stability. Here, it is demonstrated that by simply mixing 50% of formamidinium (FA+) into methylammonium lead iodide (MAPbI3), a highly crystalline, stable phase, and compact, polycrystalline grain morphology perovskite is formed by using a solvent‐mediated phase transformation process via the synergism of dimethyl sulfoxide and diethyl ether, which shows long carrier lifetime, low trap state density, and a record certified 21.8% power conversion efficiency (PCE) in pure‐iodide, alkaline‐metal‐free MA0.5FA0.5PbI3 perovskite‐based PSCs. These PSCs show very high operational stability, with 85% PCE retention upon 1000 h 1 Sun intensity illumination. A 17.33% PCE module (6.5 × 7 cm2) is also demonstrated, attesting to the scalability of such devices.  相似文献   
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