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1.
A list of microlepidoptera belonging to the superfamily Gelechioidea was produced from June trap samples from sites within the Wayne National Forest (Lawrence County), an Appalachian forest in Southern Ohio that was once a greatly disturbed area and has since re-established over a period of nearly 100 years. The composition and diversity of Lawrence county is compared to lists of gelechioid moths generated by other surveys in the eastern United States: the Great Smoky Mountains National Park, an Ohio study (Summerville and Crist 2003), and unpublished data from Connecticut (Wagner). From comparison with these studies, we address two questions: (1) How well do passive surveys of Gelechioidea compare to more labor intensive surveys? (2) How does the regenerated Wayne National Forest compare to other well documented areas with respect to gelechioid diversity? Our sample of diversity, though more narrow in time and area, compares favorably to more exhaustive sampling and demonstrates that it may be more efficient to focus on target groups in focal localities when time and resources are limited rather than conduct extensive sampling programs.  相似文献   
2.
It remains uncertain whether full T cell reconstitution can be established in HIV-infected children and adults with long-term sustained virological control by highly active antiretroviral therapy (HAART). In this study, we comprehensively analyzed various phenotypical markers of CD4 T cell recovery. In addition to measuring T cell activation and proliferation markers, CD4 T cell generation and aging of the CD4 T cell compartment were assessed by measuring TCR excision circles and the fraction of CD31-expressing naive CD4 T cells. In all children and in adults with relatively high CD4 T cell counts at start of therapy (>200 cells/microl), total CD4 T cell numbers normalized within 1 year of therapy. After long-term HAART (4.4-9.6 years), naive CD4 T cell counts had normalized in both groups. Although in adults with low baseline CD4 T cell counts (<200 cells/microl) total CD4 T cell numbers normalized eventually after at least 7 years of HAART, naive CD4 T cell counts had still not recovered. TCR excision circle data showed that thymic T cell production contributed to naive T cell recovery at all ages. The fraction of CD31-expressing naive CD4 T cells was found to be normal, suggesting that the CD4 T cell repertoire was diverse after long-term HAART. Hence, under sustained viral suppression during long-term HAART, the T cell compartment has the potential to fully recover by generating new naive T cells both in children and in adults with high baseline CD4 T cells counts. Irrespective of baseline CD4 T cell counts, reconstitution occurred without a significant effect on T cell aging as reflected by markers for replicative history.  相似文献   
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The sympathetic nervous system (SNS) plays an important role in mediating bone remodeling. However, the exact role that beta-1 adrenergic receptors (beta1AR) have in this process has not been elucidated. We have previously demonstrated the ability of dobutamine (DOB), primarily a beta1AR agonist, to inhibit reductions in cancellous bone formation and mitigate disuse-induced loss of bone mass. The purpose of this study was to characterize the independent and combined effects of DOB and hindlimb unloading (HU) on cancellous bone microarchitecture, tissue-level bone cell activity, and osteocyte apoptosis. Male Sprague-Dawley rats, aged 6-mos, were assigned to either normal cage activity (CC) or HU (n = 18/group) for 28 days. Animals were administered either daily DOB (4 mg/kg BW/d) or an equal volume of saline (VEH) (n = 9/gp). Unloading resulted in significantly lower distal femur cancellous BV/TV (−33%), Tb.Th (−11%), and Tb.N (−25%) compared to ambulatory controls (CC-VEH). DOB treatment during HU attenuated these changes in cancellous bone microarchitecture, resulting in greater BV/TV (+29%), Tb.Th (+7%), and Tb.N (+21%) vs. HU-VEH. Distal femur cancellous vBMD (+11%) and total BMC (+8%) were significantly greater in DOB- vs. VEH-treated unloaded rats. Administration of DOB during HU resulted in significantly greater osteoid surface (+158%) and osteoblast surface (+110%) vs. HU-VEH group. Furthermore, Oc.S/BS was significantly greater in HU-DOB (+55%) vs. CC-DOB group. DOB treatment during unloading fully restored bone formation, resulting in significantly greater bone formation rate (+200%) than in HU-VEH rats. HU resulted in an increased percentage of apoptotic cancellous osteocytes (+85%), reduced osteocyte number (−16%), lower percentage of occupied osteocytic lacunae (−30%) as compared to CC-VEH, these parameters were all normalized with DOB treatment. Altogether, these data indicate that beta1AR agonist treatment during disuse mitigates negative changes in cancellous bone microarchitecture and inhibits increases in osteocyte apoptosis.  相似文献   
6.
Human decomposition is a mosaic system with an intimate association between biotic and abiotic factors. Despite the integral role of bacteria in the decomposition process, few studies have catalogued bacterial biodiversity for terrestrial scenarios. To explore the microbiome of decomposition, two cadavers were placed at the Southeast Texas Applied Forensic Science facility and allowed to decompose under natural conditions. The bloat stage of decomposition, a stage easily identified in taphonomy and readily attributed to microbial physiology, was targeted. Each cadaver was sampled at two time points, at the onset and end of the bloat stage, from various body sites including internal locations. Bacterial samples were analyzed by pyrosequencing of the 16S rRNA gene. Our data show a shift from aerobic bacteria to anaerobic bacteria in all body sites sampled and demonstrate variation in community structure between bodies, between sample sites within a body, and between initial and end points of the bloat stage within a sample site. These data are best not viewed as points of comparison but rather additive data sets. While some species recovered are the same as those observed in culture-based studies, many are novel. Our results are preliminary and add to a larger emerging data set; a more comprehensive study is needed to further dissect the role of bacteria in human decomposition.  相似文献   
7.
BackgroundThe bacterial GlgE pathway is the third known route to glycogen and is the only one present in mycobacteria. It contributes to the virulence of Mycobacterium tuberculosis. The involvement of GlgE in glycogen biosynthesis was discovered twenty years ago when the phenotype of a temperature-sensitive Mycobacterium smegmatis mutation was rescued by the glgE gene. The evidence at the time suggested glgE coded for a glucanase responsible for the hydrolysis of glycogen, in stark contrast with recent evidence showing GlgE to be a polymerase responsible for its biosynthesis.MethodsWe reconstructed and examined the temperature-sensitive mutant and characterised the mutated GlgE enzyme.ResultsThe mutant strain accumulated the substrate for GlgE, α-maltose-1-phosphate, at the non-permissive temperature. The glycogen assay used in the original study was shown to give a false positive result with α-maltose-1-phosphate. The accumulation of α-maltose-1-phosphate was due to the lowering of the kcat of GlgE as well as a loss of stability 42 °C. The reported rescue of the phenotype by GarA could potentially involve an interaction with GlgE, but none was detected.ConclusionsWe have been able to reconcile apparently contradictory observations and shed light on the basis for the phenotype of the temperature-sensitive mutation.General significanceThis study highlights how the lowering of flux through the GlgE pathway can slow the growth mycobacteria.  相似文献   
8.

Background

To reduce the spread of antibiotic resistance, there is a pressing need for worldwide implementation of effective interventions to promote more prudent prescribing of antibiotics for acute LRTI. This study is a process analysis of the GRACE/INTRO trial of a multifactorial intervention that reduced antibiotic prescribing for acute LRTI in six European countries. The aim was to understand how the interventions were implemented and to examine effects of the interventions on general practitioners’ (GPs’) and patients’ attitudes.

Methods

GPs were cluster randomised to one of three intervention groups or a control group. The intervention groups received web-based training in either use of the C-reactive protein (CRP) test, communication skills and use of a patient booklet, or training in both. GP attitudes were measured before and after the intervention using constructs from the Theory of Planned Behaviour and a Website Satisfaction Questionnaire. Effects of the interventions on patients were assessed by a post-intervention questionnaire assessing patient enablement, satisfaction with the consultation, and beliefs about the risks and need for antibiotics.

Results

GPs in all countries and intervention groups had very positive perceptions of the intervention and the web-based training, and felt that taking part had helped them to reduce prescribing. All GPs perceived reducing prescribing as more important and less risky following the intervention, and GPs in the communication groups reported increased confidence to reduce prescribing. Patients in the communication groups who received the booklet reported the highest levels of enablement and satisfaction and had greater awareness that antibiotics could be unnecessary and harmful.

Conclusions

Our findings suggest that the interventions should be broadly acceptable to both GPs and patients, as well as feasible to roll out more widely across Europe. There are also some indications that they could help to engender changes in GP and patient attitudes that will be helpful in the longer-term, such as increased awareness of the potential disadvantages of antibiotics and increased confidence to manage LRTI without them. Given the positive effects of the booklet on patient beliefs and attitudes, it seems logical to extend the use of the patient booklet to all patients.
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9.

Objective

This study aims to describe the virological, immunological and clinical efficacy of protease inhibitor (PI)-based second-line antiretroviral therapy (ART) in rural South Africa.

Methods

An observational cohort study was performed on 210 patients (including 39 children) who initiated PI-based second-line therapy at least 12 months prior to data collection. Biannual clinical, immunological and virological monitoring was performed. Primary endpoints were adequate virological response (plasma HIV-1 RNA<400 copies/ml), full virological suppression (plasma HIV-1 RNA<50 copies/ml) and treatment failure (virological failure (plasma HIV-1 RNA>1000 after initial virological response) or on-going viremia (plasma HIV-1 RNA never<400 copies/ml for more than six months)). Data were analyzed by an on-treatment (OT) and intention-to-treat (ITT) approach. Analyses were primarily performed on the group of patients who switched following first-line virological failure.

Results

Median duration of follow-up after switch to second-line treatment was 20 months [IQR 11–35]. 191 patients had switched to second-line ART due to first-line virological failure. 139/191 of them (72.8%, ITT) were in care and on treatment at the end of follow-up and 11/191 (5.8%, ITT) had died. After twelve months, an adequate virological response was seen in 92/128 patients (71.9%, OT), of which 78/128 (60.9%, OT) experienced full virological suppression. Virological response remained stable after 24 months. Virological efficacy was similar amongst adult and pediatric patients. As in first-line ART, we observed a lack of correlation between virological failure and WHO-defined immunological failure.

Conclusions

Good virological outcomes following first-line failure can be achieved with PI-based, second-line antiretroviral therapy in both adult and pediatric patients in rural South Africa. Retention rates were high and virological outcomes were sustainable during the two-year follow-up period, although persisting low-level viremia occurred in a subset of patients. The observed viro-immunological dissociation emphasizes the need for virological monitoring.  相似文献   
10.

Introduction

Adherence to combination antiretroviral therapy (cART) is vital for HIV-infected adolescents for survival and quality of life. However, this age group faces many challenges to remain adherent. We used multiple data sources (role-play, focus group discussions (FGD), and in-depth interviews (IDI)) to better understand adherence barriers for Rwandan adolescents. Forty-two HIV positive adolescents (ages 12–21) and a selection of their primary caregivers were interviewed. All were perinatally-infected and received (cART) for ≥12 months. Topics discussed during FGDs and IDIs included learning HIV status, disclosure and stigma, care and treatment issues, cART adherence barriers.

Results

Median age was 17 years, 45% female, 45% orphaned, and 48% in boarding schools. We identified three overarching but inter-related themes that appeared to influence adherence. Stigma, perceived and experienced, and inadvertent disclosure of HIV status hampered adolescents from obtaining and taking their drugs, attending clinic visits, carrying their cARTs with them in public. The second major theme was the need for better support, in particular for adolescents with different living situations, (orphanages, foster-care, and boarding schools). Lack of privacy to keep and take medication came out as major barrier for adolescents living in congested households, as well the institutionalization of boarding schools where privacy is almost non-existent. The third important theme was the desire to be ‘normal’ and not be recognized as an HIV-infected individual, and to have a normal life not perturbed by taking a regimen of medications or being forced to disclose where others would treat them differently.

Conclusions

We propose better management of HIV-infected adolescents integrated into boarding school, orphanages, and foster care; training of school-faculty on how to support students and allow them privacy for taking their medications. To provide better care and support, HIV programs should stimulate caregivers of HIV-infected adolescents to join them for their clinic visits.  相似文献   
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