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71.
This report presents preliminary observational data on the sociosexual behavior of two newly formed groups of older (11.5
to 18.5 years of age, mean age of 15.3 years) bonnet monkeys observed over a period of 18 weeks. Qualitatively, their sexual
behavior was similar to that of the younger mature bonnets. The males and females engaged in species-typical proceptive and
receptive behavior patterns. The mean duration of copulations was somewhat shorter than that reported for younger mature bonnets.
Decreased sexual function was recorded in males that were chronically ill. One male that copulated infrequently died of renal
failure in the sixth week of study. Another male that was never observed copulating suffered from fatal diabetes mellitus.
One male died apparently during coitus; autopsy findings were compatible with sudden cardiac death. The findings indicate
that sexual dysfunction in aged primates can be a sign of serious illness. Sexual and agonistic behaviors for males correlated
significantly, a finding reported in studies of rhesus macaques, which are typically a more aggressive macaque subspecies.
Low sexual behavior during the first six-week period in Group A was correlated with a high amount of grooming. Possibly, increased
grooming by females serves as a reactive behavior under conditions which do not allow sexual outlet. 相似文献
72.
73.
Extraction is one of the commonest procedures in dentistry. Therefore, it is of interest to evaluate the post extraction complications in patients undergoing extractions of permanent teeth. A total of 70 adult patients who had undergone dental extractions and presented with post -operative complications were included in the study and evaluated. Data collected was statistically analyzed using SPSS software and results obtained. Most of the patients with post extraction complications were in the age group of 31-40 years (21.6%), followed by 21-30 (20.2%) and 61-70 years (20.2%). Dry socket (39.19%) was the common post extraction complication in our study especially in the age group of 31-40 years. There was a statistically significant association between age of the patients and the post extraction complications (p<0.001). In our study, post extraction complications were commonly observed in age group of 31-40 years with a predilection for males. Dry socket was the most common post extraction complication. Age of the patient has a significant effect on post extraction complications. However, gender, smoking habits and systemic diseases have no influence on post extraction complications. 相似文献
74.
Barrantes FJ Antollini SS Blanton MP Prieto M 《The Journal of biological chemistry》2000,275(48):37333-37339
The topography of nicotinic acetylcholine receptor (AChR) membrane-embedded domains and the relative affinity of lipids for these protein regions were studied using fluorescence methods. Intact Torpedo californica AChR protein and transmembrane peptides were derivatized with N-(1-pyrenyl)maleimide (PM), purified, and reconstituted into asolectin liposomes. Fluorescence mapped to proteolytic fragments consistent with PM labeling of cysteine residues in alphaM1, alphaM4, gammaM1, and gammaM4. The topography of the pyrene-labeled Cys residues with respect to the membrane and the apparent affinity for representative lipids were determined by differential fluorescence quenching with spin-labeled derivatives of fatty acids, phosphatidylcholine, and the steroids cholestane and androstane. Different spin label lipid analogs exhibit different selectivity for the whole AChR protein and its transmembrane domains. In all cases labeled residues were found to lie in a shallow position. For M4 segments, this is compatible with a linear alpha-helical structure, but not so for M1, for which "classical" models locate Cys residues at the center of the hydrophobic stretch. The transmembrane topography of M1 can be rationalized on the basis of the presence of a substantial amount of non-helical structure, and/or of kinks attributable to the occurrence of the evolutionarily conserved proline residues. The latter is a striking feature of M1 in the AChR and all members of the rapid ligand-gated ion channel superfamily. 相似文献
75.
Functional analysis of the domain structure of tumor necrosis factor-alpha converting enzyme 总被引:12,自引:0,他引:12
Reddy P Slack JL Davis R Cerretti DP Kozlosky CJ Blanton RA Shows D Peschon JJ Black RA 《The Journal of biological chemistry》2000,275(19):14608-14614
Many membrane-bound proteins, including cytokines, receptors, and growth factors, are proteolytically cleaved to release a soluble form of their extracellular domain. The tumor necrosis factor (TNF)-alpha converting enzyme (TACE/ADAM-17) is a transmembrane metalloproteinase responsible for the proteolytic release or "shedding" of several cell-surface proteins, including TNF and p75 TNFR. We established a TACE-reconstitution system using TACE-deficient cells co-transfected with TACE and substrate cDNAs to study TACE function and regulation. Using the TACE-reconstitution system, we identified two additional substrates of TACE, interleukin (IL)-1R-II and p55 TNFR. Using truncations and chimeric constructs of TACE and another ADAM family member, ADAM-10, we studied the function of the different domains of TACE in three shedding activities. We found that TACE must be expressed with its membrane-anchoring domain for phorbol ester-stimulated shedding of TNF, p75 TNFR, and IL-1R-II, but that the cytoplasmic domain is not required for the shedding of these substrates. The catalytic domain of ADAM-10 could not be functionally substituted for that of TACE. IL-1R-II shedding required the cysteine-rich domain of TACE as well as the catalytic domain, whereas TNF and p75 TNFR shedding required only the tethered TACE catalytic domain. 相似文献
76.
Alpha-conotoxins 总被引:2,自引:0,他引:2
alpha-Conotoxins (alpha-CgTxs) are a family of Cys-enriched peptides found in several marine snails from the genus Conus. These small peptides behave pharmacologically as competitive antagonists of the nicotinic acetylcholine receptor (AChR). The data indicate that (1) alpha-CgTxs are able to discriminate between muscle- and neuronal-type AChRs and even among distinct AChR subtypes; (2) the binding sites for alpha-CgTxs are located, like other cholinergic ligands, at the interface of alpha and non-alpha subunits (gamma, delta, and epsilon for the muscle-type AChR, and beta for several neuronal-type AChRs); (3) some alpha-CgTxs differentiate the high- from the low-affinity binding site found on either alpha/non-alpha subunit interface; and that (4) specific residues in the cholinergic binding site are energetically coupled with their corresponding pairs in the toxin stabilizing the alpha-CgTx-AChR complex. The alpha-CgTxs have proven to be excellent probes for studying the structure and function of the AChR family. 相似文献
77.
78.
Heterofermentative Carbohydrate Metabolism of Lactose-Impaired Mutants of Streptococcus lactis 总被引:10,自引:6,他引:4
Two mutants of Streptococcus lactis ATCC 11454 have been isolated which possess an impaired lactose-fermenting capacity; galactose utilization is also affected, but to a lesser extent. Although the Embden-Meyerhof-Parnas pathway is the major, if not the sole, pathway of carbohydrate metabolism in the three strains, the fermentation end products of the mutants are dramatically different from the typical homolactic pattern of the wild type. Under conditions of low oxygen tension and growth-limiting lactose concentrations, mutant strain T-1 produces largely formic acid, acetic acid (2:1), and ethanol rather than lactic acid. Aerated cultures produce acetic acid, CO(2) (1:1), acetyl-methylcarbinol, and diacetyl. When the mutants use galactose as an energy source, lactic acid is the major end product, but significant heterofermentative activity is observed. The aberrations responsible for the mutant phenotypes reside in the proteins which catalyze the transport and hydrolysis of galactosides. It is hypothesized that the impaired transport system of the mutants reduces the intracellular pool of glycolytic intermediates below that of the wild type. Since fructose-1, 6-diphosphate is an activator of lactic dehydrogenase in S. lactis, lactic acid production is reduced, and pathways leading to the formation of other products are expressed. 相似文献
79.
Previously we showed that feeding polyphenol-rich wild blueberries to hypertensive rats lowered systolic blood pressure. Since probiotic bacteria produce bioactive metabolites from berry polyphenols that enhance the health benefits of berry consumption, we hypothesized that adding probiotics to a blueberry-enriched diet would augment the anti-hypertensive effects of blueberry consumption. Groups (n = 8) of male spontaneously hypertensive rats were fed one of four AIN ‘93G-based diets for 8 weeks: Control (CON); 3% freeze-dried wild blueberry (BB); 1% probiotic bacteria (PRO); or 3% BB + 1% PRO (BB+PRO). Blood pressure was measured at weeks 0, 2, 4, 6, and 8 by the tail-cuff method, and urine was collected at weeks 4 and 8 to determine markers of oxidative stress (F2-isoprostanes), nitric oxide synthesis (nitrites), and polyphenol metabolism (hippuric acid). Data were analyzed using mixed models ANOVA with repeated measures. Diet had a significant main effect on diastolic blood pressure (p = 0.046), with significantly lower measurements in the BB- vs. CON-fed rats (p = 0.035). Systolic blood pressure showed a similar but less pronounced response to diet (p = 0.220), again with the largest difference between the BB and CON groups. Absolute increase in blood pressure between weeks 0 and 8 tended to be smaller in the BB and PRO vs. CON and BB+PRO groups (systolic increase, p = 0.074; diastolic increase, p = 0.185). Diet had a significant main effect on hippuric acid excretion (p<0.0001), with 2- and ~1.5-fold higher levels at weeks 4 and 8, respectively, in the BB and BB+PRO vs. PRO and CON groups. Diet did not have a significant main effect on F2-isoprostane (p = 0.159) or nitrite excretion (p = 0.670). Our findings show that adding probiotics to a blueberry-enriched diet does not enhance and actually may impair the anti-hypertensive effect of blueberry consumption. However, probiotic bacteria are not interfering with blueberry polyphenol metabolism into hippuric acid. 相似文献
80.
Ronald E. Blanton Lúcio M. Barbosa Eliana A. Reis Theomira M. Carmo Cláudio R. A. dos Santos Jackson M. Costa Peace T. Aminu Walter A. Blank Renato Barbosa Reis Isabel C. Guimar?es Luciano K. Silva Mitermayer G. Reis 《PLoS neglected tropical diseases》2015,9(3)
Urbanization is increasing across the globe, and diseases once considered rural can now be found in urban areas due to the migration of populations from rural endemic areas, local transmission within the city, or a combination of factors. We investigated the epidemiologic characteristics of urban immigrants and natives living in a neighborhood of Salvador, Brazil where there is a focus of transmission of Schistosoma mansoni. In a cross-sectional study, all inhabitants from 3 sections of the community were interviewed and examined. In order to determine the degree of parasite differentiation between immigrants and the native born, S. mansoni eggs from stools were genotyped for 15 microsatellite markers. The area received migrants from all over the state, but most infected children had never been outside of the city, and infected snails were present at water contact sites. Other epidemiologic features suggested immigration contributed little to the presence of infection. The intensity and prevalence of infection were the same for immigrants and natives when adjusted for age, and length of immigrant residence in the community was positively associated with prevalence of infection. The population structure of the parasites also supported that the contribution from immigration was small, since the host-to-host differentiation was no greater in the urban parasite population than a rural population with little distant immigration, and there had been little differentiation in the urban population over the past 7 years. Public health efforts should focus on eliminating local transmission, and once eliminated, reintroduction from distant migration is unlikely. 相似文献