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111.
Laeyendecker O Church JD Oliver AE Mwatha A Owen SM Donnell D Brookmeyer R Musoke P Jackson JB Guay L Nakabiito C Quinn TC Eshleman SH 《PloS one》2010,5(10):e13259
Background
Accurate incidence estimates are needed for surveillance of the HIV epidemic. HIV surveillance occurs at maternal-child health clinics, but it is not known if pregnancy affects HIV incidence testing.Methods
We used the BED capture immunoassay (BED) and an antibody avidity assay to test longitudinal samples from 51 HIV-infected Ugandan women infected with subtype A, C, D and intersubtype recombinant HIV who were enrolled in the HIVNET 012 trial (37 baseline samples collected near the time of delivery and 135 follow-up samples collected 3, 4 or 5 years later). Nineteen of 51 women were also pregnant at the time of one or more of the follow-up visits. The BED assay was performed according to the manufacturer''s instructions. The avidity assay was performed using a Genetic Systems HIV-1/HIV-2 + O EIA using 0.1M diethylamine as the chaotropic agent.Results
During the HIVNET 012 follow-up study, there was no difference in normalized optical density values (OD-n) obtained with the BED assay or in the avidity test results (%) when women were pregnant (n = 20 results) compared to those obtained when women were not pregnant (n = 115; for BED: p = 0.9, generalized estimating equations model; for avidity: p = 0.7, Wilcoxon rank sum). In addition, BED and avidity results were almost exactly the same in longitudinal samples from the 18 women who were pregnant at only one study visit during the follow-up study (p = 0.6, paired t-test).Conclusions
These results from 51 Ugandan women suggest that any changes in the antibody response to HIV infection that occur during pregnancy are not sufficient to alter results obtained with the BED and avidity assays. Confirmation with larger studies and with other HIV subtypes is needed. 相似文献112.
Long term bed rest with and without vibration exercise countermeasures: effects on human muscle protein dysregulation 总被引:1,自引:0,他引:1
Moriggi M Vasso M Fania C Capitanio D Bonifacio G Salanova M Blottner D Rittweger J Felsenberg D Cerretelli P Gelfi C 《Proteomics》2010,10(21):3756-3774
The present investigation, the first in the field, was aimed at analyzing differentially, on individual samples, the effects of 55 days of horizontal bed rest, a model for microgravity, on myosin heavy and myosin light chain isoforms distribution (by SDS) and on the proteome (by 2-D DIGE and MS) in the vastus lateralis (VL), a mixed type II/I (~50:50%) head of the quadriceps and in the calf soleus (SOL), a predominantly slow (~35:65%) twitch muscle. Two separate studies were performed on six subjects without (BR) and six with resistive vibration exercise (RVE) countermeasures, respectively. Both VL and SOL underwent in BR decrements of ~15% in cross-sectional area and of ~22% in maximal torque that were prevented by RVE. Myosin heavy chain distribution showed increased type I and decreased type IIA in BR both in VL and in SOL, the opposite with RVE. A substantial downregulation of proteins involved in aerobic metabolism characterized both in SOL and VL in BR. RVE reversed the pattern more in VL than in SOL, whereas proteins involved in anaerobic glycolysis were upregulated. Proteins from the Z-disk region and from costamers were differently dysregulated during bed rest (both BR and RVE), particularly in VL. 相似文献
113.
Ubiquitin over-expression promotes E6AP autodegradation and reactivation of the p53/MDM2 pathway in HeLa cells 总被引:1,自引:0,他引:1
Crinelli R Bianchi M Menotta M Carloni E Giacomini E Pennati M Magnani M 《Molecular and cellular biochemistry》2008,318(1-2):129-145
It has been established that intracellular ubiquitin pools are subject to regulatory constrains. Less certain is the mechanism by which the pool of conjugated ubiquitin shift in parallel with total ubiquitin, and how this type of regulation affects the flux of substrates through the pathway. In this study we demonstrate that ubiquitin over-expression promotes the destabilization of the ubiquitin protein ligase E6AP, by a mechanism involving self-ubiquitination, and the stabilization of p53. These results represent the very first evidence that the levels of a ubiquitin ligase can be regulated in vivo by ubiquitin abundance, supporting the idea that a strict interrelationship between pathway component activities and ubiquitin pool size exists. Interestingly, ubiquitin-induced p53 accumulation did not induce cell-cycle arrest, suggesting that although fluctuations of the intracellular ubiquitin content may actively modulate the level of regulatory proteins, this event is not per se sufficient to elicit a cellular response in terms of proliferation. 相似文献
114.
Yuki Ishii May Keu Nhiayi Edison Tse Jonathan Cheng Michele Massimino Donald L. Durden Paolo Vigneri Jean Y. J. Wang 《PloS one》2015,10(10)
Knockout serum replacement (KOSR) is a nutrient supplement commonly used to replace serum for culturing stem cells. We show here that KOSR has pro-survival activity in chronic myelogenous leukemia (CML) cells transformed by the BCR-ABL oncogene. Inhibitors of BCR-ABL tyrosine kinase kill CML cells by stimulating pro-apoptotic BIM and inhibiting anti-apoptotic BCL2, BCLxL and MCL1. We found that KOSR protects CML cells from killing by BCR-ABL inhibitors—imatinib, dasatinib and nilotinib. The protective effect of KOSR is reversible and not due to the selective outgrowth of drug-resistant clones. In KOSR-protected CML cells, imatinib still inhibited the BCR-ABL tyrosine kinase, reduced the phosphorylation of STAT, ERK and AKT, down-regulated BCL2, BCLxL, MCL1 and up-regulated BIM. However, these pro-apoptotic alterations failed to cause cytochrome c release from the mitochondria. With mitochondria isolated from KOSR-cultured CML cells, we showed that addition of recombinant BIM protein also failed to cause cytochrome c release. Besides the kinase inhibitors, KOSR could protect cells from menadione, an inducer of oxidative stress, but it did not protect cells from DNA damaging agents. Switching from serum to KOSR caused a transient increase in reactive oxygen species and AKT phosphorylation in CML cells that were protected by KOSR but not in those that were not protected by this nutrient supplement. Treatment of KOSR-cultured cells with the PH-domain inhibitor MK2206 blocked AKT phosphorylation, abrogated the formation of BIM-resistant mitochondria and stimulated cell death. These results show that KOSR has cell-context dependent pro-survival activity that is linked to AKT activation and the inhibition of BIM-induced cytochrome c release from the mitochondria. 相似文献
115.
Adam R. Boyko Pascale Quignon Lin Li Jeffrey J. Schoenebeck Jeremiah D. Degenhardt Kirk E. Lohmueller Keyan Zhao Abra Brisbin Heidi G. Parker Bridgett M. vonHoldt Michele Cargill Adam Auton Andy Reynolds Abdel G. Elkahloun Marta Castelhano Dana S. Mosher Nathan B. Sutter Gary S. Johnson John Novembre Melissa J. Hubisz Adam Siepel Robert K. Wayne Carlos D. Bustamante Elaine A. Ostrander 《PLoS biology》2010,8(8)
Domestic dogs exhibit tremendous phenotypic diversity, including a greater
variation in body size than any other terrestrial mammal. Here, we generate a
high density map of canine genetic variation by genotyping 915 dogs from 80
domestic dog breeds, 83 wild canids, and 10 outbred African shelter dogs across
60,968 single-nucleotide polymorphisms (SNPs). Coupling this genomic resource
with external measurements from breed standards and individuals as well as
skeletal measurements from museum specimens, we identify 51 regions of the dog
genome associated with phenotypic variation among breeds in 57 traits. The
complex traits include average breed body size and external body dimensions and
cranial, dental, and long bone shape and size with and without allometric
scaling. In contrast to the results from association mapping of quantitative
traits in humans and domesticated plants, we find that across dog breeds, a
small number of quantitative trait loci (≤3) explain the majority of
phenotypic variation for most of the traits we studied. In addition, many
genomic regions show signatures of recent selection, with most of the highly
differentiated regions being associated with breed-defining traits such as body
size, coat characteristics, and ear floppiness. Our results demonstrate the
efficacy of mapping multiple traits in the domestic dog using a database of
genotyped individuals and highlight the important role human-directed selection
has played in altering the genetic architecture of key traits in this important
species. 相似文献
116.
Male mating behavior and ejaculate expenditure under sperm competition risk in the eastern mosquitofish 总被引:6,自引:4,他引:6
Theory predicts that males should tailor the size of their ejaculatesaccording to temporal changes in the risk of sperm competition.Specifically, males are predicted to allocate more sperm toeach mating event with increasing risk (i.e., the probabilitythat the sperm from two males will compete for fertilization).We tested this hypothesis by using the eastern mosquitofish,a freshwater species of fish exhibiting a coercive mating systemand internal fertilization. We manipulated the perception ofsperm competition risk by adjusting the sex ratio under whichmales were maintained over 8 days. Males were housed eitherwith three females and one male (simulating high sperm competitionrisk) or with four females (low risk). After the treatment,we presented each test male individually to an unfamiliar male-deprivedfemale for 30 minutes and observed his mating behavior. We thenartificially stripped the test males of sperm and recoveredthe ejaculates from the females. Our results revealed that malesin the high-risk group performed higher levels of mating activityand sperm expenditure (i.e., used up more of their sperm reserves)than did low-risk males. A control experiment, in which testmales were treated but did not participate in the mating trials,revealed no significant difference in the number of sperm strippedfrom high- and low-risk males, indicating that sperm productionwas not affected by the treatment. We did not detect a differencein the number of sperm retrieved from females among the groups,raising the possibility that some sperm are lost during matingactivity, either through ejaculation with incomplete or interruptedpenetration, or via female ejection. 相似文献
117.
Michelino Di Rosa Corinne De Gregorio Giulia Malaguarnera Michele Tuttobene Filomena Biazzo Lucia Malaguarnera 《Molecular and cellular biochemistry》2013,374(1-2):73-80
Acidic mammalian chitinase (AMCase) and chitotriosidase (CHIT-1) are two active chitinases expressed in humans. The chitinase activity of AMCase was found to be causative in allergic inflammation and its expression was found to be induced by interleukin-13. CHIT1-1 is expressed by phagocytic cells and extremely high levels are seen in lysosomal storage diseases. Despite that AMCase expression in the inflammation is under investigation, little is known regarding its regulation during macrophages' full maturation and polarization. In this study, we compared AMCase and CHIT-1 modulation during monocyte to macrophage transition and polarization. Gene expression analysis was investigated by real-time PCR from mRNA of human monocytes obtained from buffy coat of healthy volunteers, from mRNA of polarized to classically activated macrophages (or M1), obtained by interferon (IFN)-γ and lipopolysaccharide (LPS) treatment, and from mRNA of alternatively activated macrophages (or M2) obtained by interleukin (IL)-4 exposure. Our results showed that the expression of AMCase and CHIT-1 were differently modulated in HMMs at different stage of maturation. The behavior of these two active chitinase suggests that in the immune response their role is complementary. 相似文献
118.
Nisio CD Brunetti L Esposito DL Recinella L Orlando G Michelotto B Vacca M 《Peptides》2003,24(8):1231-1236
Chromatin-derived acidic peptides (ACPs) have been shown to acutely modulate hypothalamic catecholamine release. To investigate whether this effect is mediated through membrane polysialylated neural-cell adhesion molecule (PSA-N-CAM), we pretreated rat hypothalamic synaptosomes with neuraminidase enzyme, which partially cleaves sialic acid residues from N-CAM, and perfused them with ACP-1 (Asp-Asp-Ser-Asp-Glu-Glu-Asn) or a more lipophilic derivative, ACP-2 ([Ala-Ile-Ser-Pro]-Asp-Asp-Ser-Asp-Glu-Glu-Asn). We have found that neuraminidase completely abolish the inhibitory effect of ACP-1 on dopamine release, while the inhibitory activity of ACP-1 on norepinephrine release is partially lost. On the other hand, ACP-2 inhibition of dopamine release is not modified by neuraminidase pretreatment. 相似文献
119.
Michele?Cesari Lara?Maistrello Lucia?Piemontese Raoul?Bonini Paride?Dioli Wonhoon?Lee Chang-Gyu?Park Georgios?K.?Partsinevelos Lorena?Rebecchi Roberto?GuidettiEmail authorView authors OrcID profile 《Biological invasions》2018,20(4):1073-1092
Halyomorpha halys is an invasive stink bug pest originating from East Asia. In Europe, it was first detected in Switzerland in 2004. It is now present in thirteen countries, and seems to be spreading throughout the continent. In Italy, where it has been recorded since 2012, other than being an urban nuisance, it is causing severe damage in commercial fruit orchards. An integrated approach, using current and previous observational data in space and time and molecular information, was used to identify the genetic diversity of this pest in Europe, its invasion history, and the potential pathways of entry and diffusion. The analysis of 1175 bp of mitochondrial DNA cytochrome c oxidase I and II genes (cox1, cox2) led to the identification of twenty previously unknown haplotypes. The European distribution of H. halys is the result of multiple invasions that are still in progress, and, in some cases, it was possible to identify the specific Asian areas of origin. Moreover, secondary invasions could have occurred among European countries by a bridgehead effect. In Italy, the data were more clearly related to their temporal occurrence, allowing for a clearer reading of the patterns of invasion and dispersion. After having successfully established in localized areas, H. halys further expanded its range by an active dispersion process and/or by jump dispersal events due to passive transport. The multiple introductions from different areas of the native range together with the different patterns of diffusion of H. halys, may hamper the pest management strategies for its containment. 相似文献
120.
Riccardo Danielli Roberto Patuzzo Anna Maria Di Giacomo Gianfranco Gallino Andrea Maurichi Annabella Di Florio Ornella Cutaia Andrea Lazzeri Carolina Fazio Clelia Miracco Leonardo Giovannoni Giuliano Elia Dario Neri Michele Maio Mario Santinami 《Cancer immunology, immunotherapy : CII》2015,64(8):999-1009