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341.
Transmission of HIV first results in an acute infection, followed by an apparently asymptomatic period that averages ten years. In the absence of antiretroviral treatment, most patients progress into a generalized immune dysfunction that culminates in death. The length of the asymptomatic period varies, and in rare cases infected individuals never progress to AIDS. Other individuals whose behavioral traits put them at high-risk of HIV transmission, surprisingly appear resistant and never succumb to infection. These unique cases highlight the fact that susceptibility to HIV infection and progression to disease are complex traits modulated by environmental and genetic factors. Recent evidence has indicated that natural variations in host genes can influence the outcome of HIV infection and its transmission. In this review we summarize the available literature on the roles of cellular factors and their genetic variation in modulating HIV infection and disease progression. 相似文献
342.
BackgroundIn the context of the high incidence of breast cancer and the high frequency of breast cosmetic surgeries, malignant and/or premalignant lesions are frequently detected incidentally in postoperative histopathology specimens. The current literature does not provide clear practice guidelines for the use of preoperative imaging prior to non-oncological breast surgeries.ObjectivesIn this study, we aimed to determine the current practices of plastic surgeons at King Abdulaziz University Hospital (KAUH) and their use of preoperative breast imaging before non-oncological breast surgeries.DesignNon-intervention/ retrospective record review.SettingsDepartment of Radiology at King Abdulaziz University Hospital (KAUH).MethodsIn 08/06/2017 at King Abdulaziz University Hospital, we conducted a single-center, retrospective chart review of the medical files of candidates for non-oncological breast surgery in order to examine preoperative imaging requests by plastic surgeons in the period 01/01/2013 to 08/06/2017.Main outcome measuresThe practice of plastic surgeons at KAUH in requesting preoperative imaging prior non-oncological breast surgeries.Sample size104 patients.ResultsWe found that, in the period 2013 to 2017, 104 women who underwent non-oncological breast surgeries were evaluated for recent preoperative breast imaging. Only 37 patients (35.6%) were found to have had preoperative imaging, and only less than one fifth (19.4%) of those 37 patients had abnormal preoperative imaging results, all of which were negative for malignancy.ConclusionsAlthough the yield of malignancy on preoperative breast imaging was zero in women seeking non-oncological breast surgeries at KAUH, we recommend the establishment of unified practice guidelines to be followed by plastic surgeons for better postoperative screening in different risk groups.LimitationsLack of follow up of patients postoperatively for any development of malignancy. 相似文献
343.
Teresa Lama Susan E. Del Valle Nicolas Genest William D. Lubell 《International journal of peptide research and therapeutics》2007,13(1-2):355-366
Pro-Aib hydroxyethylene isosteres (S,R)- and (S,S)-7 were synthesized by cascade addition of 2-methyl-1-propenylmagnesium bromide to Boc-Pro-OMe in the presence of CuCN, followed
by ketone reduction and olefin oxidation. By protecting the amine and hydroxyl groups in an oxazolidinone ring, hydroxyethylene
isosteres 7 were successfully incorporated into Boc-Phe-Pro- ψ -[CH-(OH)-CH2]-Aib-NHBn(α -Me) (S,R)-and (S,S)-11, which were characterized by 1H NMR and IR spectroscopy. Examination of the NOESY spectra and the influence of solvent changes on the chemical shifts of
the amide and carbamate proton signals for (S,R)-and (S,S)-11 indicated that both hydroxyethylene isosteres could adopt compact turn structures. The alcohol appears to act as a hydrogen
donor in a seven-membered ring intramolecular hydrogen bond. In addition, analysis of the respective peptide (S,S)-16, in which the hydroxyl group was masked as a methyl ether, showed that the turn conformation was disrupted, and indicated
the importance of the alcohol as a hydrogen-bond donor for turn stability.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
344.
Trypoxylon is a genus of solitary crabronid wasps whose population
genetics is poorly known. The purpose of the present study was to investigate the
genetic variation and differentiation among five populations of Trypoxylon
albitarse, a species widely distributed throughout the Neotropics, with
records from Panama to northern Argentina. Eight species-specific microsatellite loci
were used for genotyping 96 adult wasps (one female per nest) sampled at five sites
in Brazil. The analysis of allelic richness and private alleles indicated high
genetic diversity in the populations sampled. Pairwise comparisons using the
F
st and D
est indices revealed significant differentiation for all, but one pair of
populations. F
st, D
est, AMOVA and assignment test values pointed to inter-population differentiation.
Additionally, the analysis of population structure using Bayesian and PCA methods
characterized two alternative genetic groups. The Mantel test indicated no
correlation between genetic and geographic distances. Despite evidence of
considerable dispersal capacity for T. albitarse, the data indicate
low to moderate population structuring in this species. 相似文献
345.
Lama Talje Khaled Ben El Kadhi Kaleem Atchia Thierry Tremblay-Boudreault Sébastien Carreno Benjamin H. Kwok 《FEBS letters》2014
The kinesin-13 family of microtubule depolymerases is a major regulator of microtubule dynamics. RNA interference-induced knockdown studies have highlighted their importance in many cell division processes including spindle assembly and chromosome segregation. Since microtubule turnovers and most mitotic events are relatively rapid (in minutes or seconds), developing tools that offer faster control over protein functions is therefore essential to more effectively interrogate kinesin-13 activities in living cells. Here, we report the identification and characterization of a selective allosteric kinesin-13 inhibitor, DHTP. Using high resolution microscopy, we show that DHTP is cell permeable and can modulate microtubule dynamics in cells. 相似文献
346.
Silvia Nassif Del Lama Luiza Helena da Silva Avelar João Luiz Xavier Nascimento 《Journal of Field Ornithology》2015,86(4):283-287
Seasonal migration and the dispersal of juvenile and adult Wood Storks (Mycteria americana) after breeding have been documented in the United States, but little is known about the post‐breeding movements of Wood Storks in South America. Our objective was to identify the locations of post‐breeding areas used by Wood Storks banded as nestlings in breeding colonies in Brazil by analyzing banding data. During the period from 1984 to 2007, 2543 nestlings were banded at breeding colonies in three regions of Brazil, with most (94%) banded in the Pantanal wetland in west‐central Brazil. Seventeen bands were subsequently recovered, with most (14) recovered in southern Brazil and northern Argentina. The mean distance between banding and recovery sites was 1265 km. Our results suggest that Wood Stork movements from breeding areas in Brazil are, as also reported in the United States, in response to changing water levels. The rainy season begins at the end of the breeding season and, in apparent response to rising water levels, Wood Storks in our study moved to drier areas further south with shallower water where they can forage more efficiently. Because only a small percentage of the area where Wood Stork bands were recovered in our study is currently protected, measures are needed to prevent habitat destruction and preserve wetland habitats used by Wood Storks during the post‐breeding period in southern Brazil and Argentina. 相似文献
347.
348.
Rogrio O. Souza Marco A. Del Lama Marcelo Cervini Norma Mortari Thomas Eltz Yvonne Zimmermann Carola Bach Berry J. Brosi Sevan Suni J. Javier G. Quezada‐Eun Robert J. Paxton 《Evolution; international journal of organic evolution》2010,64(11):3318-3326
Allozyme analyses have suggested that Neotropical orchid bee (Euglossini) pollinators are vulnerable because of putative high frequencies of diploid males, a result of loss of sex allele diversity in small hymenopteran populations with single locus complementary sex determination. Our analysis of 1010 males from 27 species of euglossine bees sampled across the Neotropics at 2–11 polymorphic microsatellite loci revealed only five diploid males at an overall frequency of 0.005 (95% CIs 0.002–0.010); errors through genetic nondetection of diploid males were likely small. In contrast to allozyme‐based studies, we detected very weak or insignificant population genetic structure, even for a pair of populations >500 km apart, possibly accounting for low diploid male frequencies. Technical flaws in previous allozyme‐based analyses have probably led to considerable overestimation of diploid male production in orchid bees. Other factors may have a more immediate impact on population persistence than the genetic load imposed by diploid males on these important Neotropical pollinators. 相似文献
349.
Cameron R. Love Sumit Gautam Chamala Lama Nhu Hoa Le Brigitte Dauwalder 《Genes, Brain & Behavior》2023,22(1):e12836
The blood brain barrier (BBB) has the essential function to protect the brain from potentially hazardous molecules while also enabling controlled selective uptake. How these processes and signaling inside BBB cells control neuronal function is an intense area of interest. Signaling in the adult Drosophila BBB is required for normal male courtship behavior and relies on male-specific molecules in the BBB. Here we show that the dopamine receptor D2R is expressed in the BBB and is required in mature males for normal mating behavior. Conditional adult male knockdown of D2R in BBB cells causes courtship defects. The courtship defects observed in genetic D2R mutants can be rescued by expression of normal D2R specifically in the BBB of adult males. Drosophila BBB cells are glial cells. Our findings thus identify a specific glial function for the DR2 receptor and dopamine signaling in the regulation of a complex behavior. 相似文献
350.
Hani T. Fadel Randa A. Sultan Lama M. Alrasheedi Jumanah G. Alsadiq Reham T. Kattuah Manal I. Al-Malik Yasser A. Rhbeini 《Saudi Journal of Biological Sciences》2021,28(1):210-216
BackgroundAccess to dental care is of growing importance to individuals with chronic illnesses and policymakers alike.ObjectivesTo explore personal views of diabetic and non-diabetic women regarding their oral health and access to dental care.MethodsA qualitative study was performed involving 6 diabetic and 6 non-diabetic female hospital attendees. A thematic framework approach was used to analyze the interviews.ResultsResponses yield three emerging central themes: oral health impact, self-maintained oral health and dental service delivery and costs. Personal views varied particularly in oral health self-perception and visiting the dentist. Certain drawbacks shadowed the quality of care in governmental and private sectors. Response variations were observed among diabetics and non-diabetics.ConclusionWithin the study limits, female hospital attendees had variable responses on how they looked upon their oral health. A variation in oral hygiene practices and visiting the dentist was observed. Participants believed that governmental and private clinics offered high quality care, with high treatment costs in private clinics and long waiting times in the public service being the main drawbacks. Practical Significance: Importance of supporting patients, educating practitioners and alarming policymakers about the impact of oral health problems and access to dental care. 相似文献