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991.
G. Gautam 《Theriogenology》2009,71(9):1451-1461
Two hundred fifty-eight Holstein cows (n = 344 lactations) from seven dairy herds were examined every month by vaginoscopy and transrectal palpation to determine the prevalence of urovagina, to investigate its effects on fertility, and to determine some risk factors for urovagina. Accumulation of urine in the vagina of a cow was diagnosed as urovagina and was classified into mild (urine only on the floor of vagina), moderate (urine covering less than or equal to half portion of the external cervical os), or severe (urine covering more than half or whole portion of the external cervical os). In total, 26.7% of lactations had urovagina (mild 11.3%, moderate 11.0%, and severe 4.4%). Survival analysis was used to derive the case definition of clinically relevant urovagina based on the factors associated with increased time to conception. Only moderate (hazard ratio [HR] = 0.39) and severe (HR = 0.20) degrees of urovagina were associated with reduction in pregnancy rate and thus defined as clinically relevant urovagina. Cows with clinically relevant urovagina had decreased AI submission rate (HR = 0.52) and pregnancy rate (HR = 0.35), required more inseminations per conception (5 vs. 2; P < 0.001), had more days open (370 vs. 136; P < 0.001), and were more likely not to get pregnant by 210 d postpartum (odds ratio [OR] = 6.62) and to be culled for any reasons (OR = 5.32) or for reproductive reasons (OR = 9.54) compared with those in cows with no urovagina. Cows with clinically relevant urovagina had a higher risk of endometritis (36.4% vs. 9.2%; P < 0.001) compared with that in cows without urovagina. Cow, low BCS at first postpartum examination (OR = 2.85), endometritis within 60 d (OR = 2.50), and horizontal vulva (OR = 9.30) were risk factors for urovagina. In conclusion, 15.4% of lactations had clinically relevant urovagina that increased the risk of endometritis and had detrimental effects on fertility. Individual susceptibility, low BCS, and horizontal vulva increased the risk of diagnosing urovagina in Holstein cows.  相似文献   
992.
Sarath G  Bethke PC  Jones R  Baird LM  Hou G  Mitchell RB 《Planta》2006,223(6):1154-1164
The nitric oxide (NO) donor sodium nitroprusside (SNP) significantly promoted germination of switchgrass (Panicum virgatum L. cv Kanlow) in the light and in the dark at 25°C, across a broad range of concentrations. SNP also promoted seed germination in two other warm-season grasses. A chemical scavenger of NO inhibited germination and blocked SNP stimulation of seed germination. The phenolic (+)-catechin acted synergistically with SNP and nitrite in promoting seed germination. Acidified nitrite, an alternate NO donor also significantly stimulated seed germination. Interestingly, sodium cyanide, potassium ferricyanide and potassium ferrocyanide at 200 μM strongly enhanced seed germination as well, whereas potassium chloride was without effect. Ferrocyanide and cyanide stimulation of seed germination was blocked by an NO scavenger. Incubation of seeds with a fluorescent NO-specific probe provided evidence for NO production in germinating switchgrass seeds. Abscisic acid (ABA) at 10 μM depressed germination, inhibited root elongation and essentially abolished coleoptile emergence. SNP partially overcame ABA effects on radicle emergence but did not overcome the effects of ABA on coleoptile elongation. Light microscopy indicated extension of the radicle and coleoptiles in seeds maintained on water or on SNP after 2 days. In contrast, there was minimal growth of the radicle and coleoptile in ABA-treated seeds even after 3–4 days. These data indicate that seed germination of warm-season grasses is significantly influenced by NO signaling pathways and document that NO could be an endogenous trigger for release from dormancy in these species.  相似文献   
993.
The cDNAs encoding for three subtypes of adrenergic receptors, α1A-, α1B- and α1D-ARs, were cloned and expressed in HEK 293 cells. Expression of α1A- and α1B-AR subtypes in HEK 293 cells was stable even with increased passages but that of α1D-AR was not. Cellular localization studies using immunofluorescence and flow cytometry revealed that expression of α1A- and α1B-ARs was primarily localized on the cell membrane whereas expression of α1D-AR was␣predominantly intracellular. Our studies clearly demonstrated that the culturing of the recombinant cell lines expressing α1D-AR in charcoal/dextran treated fetal bovine serum (FBS) resulted in targeting of α1D-AR to the cell membrane and thus, significantly improving its stability and availability for ligand binding studies.Sunil M. Khattar, Roop Singh Bora and Priyanka Priyadarsiny contributed equally to this work.  相似文献   
994.
In order to understand the pathogenesis of estradiol induced effects in the seminiferous epithelium, studies were undertaken in adult rats with estradiol-3-benzoate administered for different durations. After 30 d of treatment, a significant rise in lipid peroxidation with concomitant fall in the activities of superoxide dismutase and catalase was observed. Both, serum and intra-testicular testosterone levels were found severely depleted. Seminiferous epithelium was devoid of elongated spermatids and spermatozoa by 30 d of treatment. Number of spermatocytes and round spermatids were significantly (p < 0.001) reduced. Flowcytometric analysis confirmed a drastic reduction of the haploid cell population (1c peak). Beginning from day 10 of treatment, there was a consistent rise in the number of pyknotic/apoptotic germ cells in the seminiferous epithelium. A gradual increase in Bax protein expression was observed with the duration of treatment. The shift in Bax immunostaining from the cytoplasm and nucleus of germ cells (at 10 d of treatment) to only nuclei of cells by 30 d of treatment was also noticed. By this time testicular tissue showed three-fold increase in caspase-8 enzyme activity. Viable testicular cells isolated in vitro decreased drastically subsequent to different periods of estradiol treatment. The above findings substantiate the fact that the testicular pathogenesis of estradiol benzoate treatment may be primarily because of altered reproductive hormone levels and high oxidative stress leading to germ cell apoptosis and subsequent germ cell loss in the seminiferous epithelium.  相似文献   
995.

Background

Aspergillus fumigatus, a widely distributed fungus, has been implicated in causing life threatening infections as well as severe asthma and allergic diseases in man. Allergic affliction like allergic bronchopulmonary aspergillosis (ABPA) is a disabling lung disease frequently seen in patients with asthma and cystic fibrosis. Immunodiagnosis of the former is comparatively easier due to the availability of purified antigens and sensitive methods. However, this is not true with cystic fibrosis patients where the prevalence of ABPA is fairly high and the morbidity and mortality are significant.

Methods

In the present study, we have evaluated purified recombinant allergens from A. fumigatus, namely Asp f 1, f 2, f 3, f 4, and f 6 using ELISA and a semi-automated method (ImmunoCAP). We studied 17 patients each from cystic fibrosis with ABPA, and cystic fibrosis with asthma, 22 cystic fibrosis with no ABPA or asthma, and 11 age matched controls.

Results

The results indicate that no antigen, antibody or method is capable of differentiating cystic fibrosis (CF) with ABPA from other CF patients, although some allergens showed strong reaction or showed more prevalence among the patients studied.

Conclusion

When results of several allergens such as Asp f 1, f 2, f 3, f 4, and f 6 in their binding to IgA, IgG, and IgE antibodies were analyzed, a more strong discrimination of CF patients with ABPA was possible from the other groups studied.  相似文献   
996.
997.
A series of new benzoxazepine derivatives substituted with different alkoxy and aryloxy group were synthesized comprising synthetic steps of Mitsunobu reaction, lithium aluminum hydride (LAH) reduction, followed by debenzylation and finally intramolecular Mitsunobu cyclization. The new benzoxazepines specifically inhibited growth of breast cancer cell lines, MCF-7 and MDA-MB-231, but lack cytotoxicity to normal HEK-293 cells. The cell growth inhibition induced by the active compounds was due to cell cycle arrest at G0/G1 phase. The active compound could cause significant reduction in tumor volume of MCF-7 xenograft tumor in nude mice model and their activity was comparable to that of tamoxifen citrate at 16 mg kg?1 dose at 30 days of treatment. The identified most active compounds of the series have specific advantages as anti-cancer agent in breast cancer than tamoxifen.  相似文献   
998.
Various 2,3′-anhydro analogs of 5-substituted 1-(2-deoxy-β-d-lyxofuranosyl)uracils (1015) and a related 1-(3-O-mesyl-2-deoxy-β-d-lyxofuranosyl) pyrimidine nucleoside analog (18) have been synthesized for evaluation as a new class of potential anti-HBV agents. The compounds 10, 12, and 15 demonstrated most potent anti-HBV activities against duck HBV (DHBV) and human HBV with EC50 values in the range of 2.5–10 and 5–10 μg/mL, respectively, at non-toxic concentrations (CC50 = >200 μg/mL). The nucleoside 18 also demonstrated significant anti-HBV activity against DHBV with an EC50 value of 2.5 μg/mL, however, it was less active against HBV in 2.2.15 cells (EC50 = >10 μg/mL).  相似文献   
999.
1000.
AmpC is a group I, class C -lactamase present in most Enterobacteriaceae and in Pseudomonas aeruginosa and other nonfermenting gram-negative bacilli. The β-lactam class of antibiotics is one of the most important structural classes of antibacterial compounds and act by inhibiting the bacterial D ,D - transpeptidases that are responsible for the final step of peptidoglycan cross-linking. Our main aim in the study is to screen possible inhibitors against AmpC / β - lactamase (an enzyme responsible for antimicrobial activity in Pseudomonas aeruginosa), through virtual screening of 1364 NCI (National Cancer Institute) diversity set II compounds. Homology Model of AmpC / β - lactamase was constructed using MODELLER and the Model was validated using PROCHECK and Verify 3D programs to obtain a stable structure, which was further used for virtual screening of NCI (National Cancer Institute) diversity set II compounds through molecular Docking studies using Autodock. The amino acid sequence of the β - lactamase was also subjected to ScanProsite web server to find any pattern present in the sequence. After the prediction of 3-dimensional model of AmpC/ β-lactamase, the possible Active sites ofβ - lactamase were determined using LIGSITE(csc) and CastP web servers simultaneously. The Docked complexes were validated and Enumerated based on the Autodock Scoring function to pick out the best inhibitor based on Autodock energy score. Thus from the entire 1364 NCI diversity set II compounds which were Docked, the best four docking solutions were selected (ZINC12670903, ZINC17465965, ZINC11681166 and ZINC13099024). Further the Complexes were analyzed through LIGPLOT for their interaction for the 4 best docked NCI diversity set II compounds. Thus from the Complex scoring and binding ability it is deciphered that these NCI diversity set II compounds could be promising inhibitors for Pseudomonas aeruginosa using AmpC /β - lactamase as Drug target yet pharmacological studies have to confirm it.  相似文献   
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