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121.
We conpared three fecal steroid metabolite assays for their usefulness in detecting pregnalcy among free-ranging Rocky Mountain bighorn sheep (Ovis canadensis canadensis) from Bighorn Canyon National Recreation Area, Wyoming and Montana (USA) and captive bighorn ewes at ZooMontana in Billings, Montana. Fecal samples were collected from 11 free-ranging, radio-collared bighorn ewes in late January-May 2001 and from 20 free-ranging, radio-collared ewes in late March to mid-May 2002. Free-ranging ewes were monitored the following spring to determine whether or not they lambed. In addition, two captive ewes were studied at ZooMontana. With three exceptions, free-ranging bighorn ewes that produced lambs had nonspecific progesterone metabolite (iPdG) levels of >1800 ng/g feces and iPdG levels >7000 ng/gm feces when samples were collected between early March and mid-May. Samples collected earlier in the year were inconclusive. One false negative was suspected to be the result of sample collection error. Of the captive ewes, nonspecific pregnanediol-3alpha-glucuronide (PdG) and iPdG followed a predictable curve over the course of the 180-day pregnancies. We conclude that estrone conjugates are not useful in diagnosing pregnancy; however, fecal steroid analysis of PdG and iPdG can be used to accurately determine pregnancy and reproductive function in bighorn sheep. This holds great potential as a noninvasive technique for understanding the role of reproductive disease in wild bighom sheep.  相似文献   
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Motivations: Biclustering is a clustering method that simultaneously clusters both the domain and range of a relation. A challenge in multiple sequence alignment (MSA) is that the alignment of sequences is often intended to reveal groups of conserved functional subsequences. Simultaneously, the grouping of the sequences can impact the alignment; precisely the kind of dual situation biclustering is intended to address. RESULTS: We define a representation of the MSA problem enabling the application of biclustering algorithms. We develop a computer program for local MSA, BlockMSA, that combines biclustering with divide-and-conquer. BlockMSA simultaneously finds groups of similar sequences and locally aligns subsequences within them. Further alignment is accomplished by dividing both the set of sequences and their contents. The net result is both a multiple sequence alignment and a hierarchical clustering of the sequences. BlockMSA was tested on the subsets of the BRAliBase 2.1 benchmark suite that display high variability and on an extension to that suite to larger problem sizes. Also, alignments were evaluated of two large datasets of current biological interest, T box sequences and Group IC1 Introns. The results were compared with alignments computed by ClustalW, MAFFT, MUCLE and PROBCONS alignment programs using Sum of Pairs (SPS) and Consensus Count. Results for the benchmark suite are sensitive to problem size. On problems of 15 or greater sequences, BlockMSA is consistently the best. On none of the problems in the test suite are there appreciable differences in scores among BlockMSA, MAFFT and PROBCONS. On the T box sequences, BlockMSA does the most faithful job of reproducing known annotations. MAFFT and PROBCONS do not. On the Intron sequences, BlockMSA, MAFFT and MUSCLE are comparable at identifying conserved regions. AVAILABILITY: BlockMSA is implemented in Java. Source code and supplementary datasets are available at http://aug.csres.utexas.edu/msa/  相似文献   
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The endoplasmic reticulum (ER) is a highly dynamic organelle. It is composed of four subcompartments including nuclear envelope (NE), rough ER (rER), smooth ER (sER) and transitional ER (tER). The subcompartments are interconnected, can fragment and dissociate and are able to reassemble again. They coordinate with cell function by way of protein regulators in the surrounding cytosol. The activity of the many associated molecular machines of the ER as well as the fluid nature of the limiting membrane of the ER contribute extensively to the dynamics of the ER. This review examines the properties of the ER that permit its isolation and purification and the physiological conditions that permit reconstitution both in vitro and in vivo in normal and in disease conditions.  相似文献   
125.
TNF-alpha influences morbidity and mortality during the course of endotoxemia. However, the complex pleiotropic functions of TNF-alpha remain poorly understood. We evaluated how hepatic induction of NF-kappaB and TNF-alpha influence survival and hepatocellular death in a lethal murine model of endotoxic shock. Using dominant-negative viral vectors to inhibit the IKK complex, we demonstrate through this study that the liver is a major source of TNF-alpha during the course of lethal endotoxemia and that IKKbeta (but not IKKalpha) is predominantly responsible for activating NF-kappaB and TNF-alpha in the liver after LPS administration. Using TNF-alpha knockout mice and hepatic-specific inhibition of IKKbeta, we demonstrate that the status of TNF-alpha and NF-kappaB balances necrotic and apoptotic fates of hepatocytes in the setting of endotoxemia. In the presence of TNF-alpha, inhibiting hepatic IKKbeta resulted in increased survival, reduced serum proinflammatory cytokines, and reduced hepatocyte necrosis in response to a lethal dose of endotoxin. In contrast, inhibiting hepatic IKKbeta in TNF-alpha knockout mice resulted in decreased survival and increased caspase 3-mediated hepatocyte apoptosis after endotoxin challenge, despite a reduced proinflammatory cytokine response. In the presence of TNF-alpha, NF-kappaB-dependent hepatocellular necrosis predominated, while in the absence of TNF-alpha, NF-kappaB primarily influenced apoptotic fate of hepatocytes. Changes in JNK phosphorylation after LPS challenge were also dynamically affected by both IKKbeta and TNF-alpha; however, this pathway could not solely explain the differential outcomes in hepatocellular fates. In conclusion, our studies demonstrate that induction of NF-kappaB and TNF-alpha balances protective (antiapoptotic) and detrimental (proinflammatory) pathways to determine hepatocellular fates during endotoxemia.  相似文献   
126.
We conducted a phase 1 double-blind randomised controlled trial (RCT) of a HIV-1 envelope protein (CN54 gp140) candidate vaccine delivered vaginally to assess immunogenicity and safety. It was hypothesised that repeated delivery of gp140 may facilitate antigen uptake and presentation at this mucosal surface. Twenty two healthy female volunteers aged 18-45 years were entered into the trial, the first receiving open-label active product. Subsequently, 16 women were randomised to receive 9 doses of 100 μg of gp140 in 3 ml of a Carbopol 974P based gel, 5 were randomised to placebo solution in the same gel, delivered vaginally via an applicator. Participants delivered the vaccine three times a week over three weeks during one menstrual cycle, and were followed up for two further months. There were no serious adverse events, and the vaccine was well tolerated. No sustained systemic or local IgG, IgA, or T cell responses to the gp140 were detected following vaginal immunisations. Repeated vaginal immunisation with a HIV-1 envelope protein alone formulated in Carbopol gel was safe, but did not induce local or systemic immune responses in healthy women. TRIAL REGISTRATION: ClinicalTrials.gov NCT00637962.  相似文献   
127.
BackgroundNatural killer (NK) cells derived from patients with cancer exhibit diminished cytotoxicity compared with NK cells from healthy individuals. We evaluated the tumor response and in vivo expansion of allogeneic NK cells in recurrent ovarian and breast cancerMethodsPatients underwent a lymphodepleting preparative regimen: fludarabine 25 mg/m2 × 5 doses, cyclophosphamide 60 mg/kg × 2 doses, and, in seven patients, 200 cGy total body irradiation (TBI) to increase host immune suppression. An NK cell product, from a haplo-identical related donor, was incubated overnight in 1000 U/mL interleukin (IL)-2 prior to infusion. Subcutaneous IL-2 (10 MU) was given three times/week × 6 doses after NK cell infusion to promote expansion, defined as detection of ≥100 donor-derived NK cells/μL blood 14 days after infusion, based on molecular chimerism and flow cytometryResultsTwenty (14 ovarian, 6 breast) patients were enrolled. The median age was 52 (range 30–65) years. Mean NK cell dose was 2.16 × 107cells/kg. Donor DNA was detected 7 days after NK cell infusion in 9/13 (69%) patients without TBI and 6/7 (85%) with TBI. T-regulatory cells (Treg) were elevated at day +14 compared with pre-chemotherapy (P = 0.03). Serum IL-15 levels increased after the preparative regimen (P = < 0.001). Patients receiving TBI had delayed hematologic recovery (P = 0.014). One patient who was not evaluable had successful in vivo NK cell expansionConclusionsAdoptive transfer of haplo-identical NK cells after lymphodepleting chemotherapy is associated with transient donor chimerism and may be limited by reconstituting recipient Treg cells. Strategies to augment in vivo NK cell persistence and expansion are needed.  相似文献   
128.
Precise annotation of genes or open reading frames is still a difficult task that results in divergence even for data generated from the same genomic sequence. This has an impact in further proteomic studies, and also compromises the characterization of clinical isolates with many specific genetic variations that may not be represented in the selected database. We recently developed software called multistrain mass spectrometry prokaryotic database builder (MSMSpdbb) that can merge protein databases from several sources and be applied on any prokaryotic organism, in a proteomic-friendly approach. We generated a database for the Mycobacterium tuberculosis complex (using three strains of Mycobacterium bovis and five of M. tuberculosis), and analyzed data collected from two laboratory strains and two clinical isolates of M. tuberculosis. We identified 2561 proteins, of which 24 were present in M. tuberculosis H37Rv samples, but not annotated in the M. tuberculosis H37Rv genome. We were also able to identify 280 nonsynonymous single amino acid polymorphisms and confirm 367 translational start sites. As a proof of concept we applied the database to whole-genome DNA sequencing data of one of the clinical isolates, which allowed the validation of 116 predicted single amino acid polymorphisms and the annotation of 131 N-terminal start sites. Moreover we identified regions not present in the original M. tuberculosis H37Rv sequence, indicating strain divergence or errors in the reference sequence. In conclusion, we demonstrated the potential of using a merged database to better characterize laboratory or clinical bacterial strains.  相似文献   
129.
Mountain lions (Puma concolor) are often difficult to monitor because of their low capture probabilities, extensive movements, and large territories. Methods for estimating the abundance of this species are needed to assess population status, determine harvest levels, evaluate the impacts of management actions on populations, and derive conservation and management strategies. Traditional mark–recapture methods do not explicitly account for differences in individual capture probabilities due to the spatial distribution of individuals in relation to survey effort (or trap locations). However, recent advances in the analysis of capture–recapture data have produced methods estimating abundance and density of animals from spatially explicit capture–recapture data that account for heterogeneity in capture probabilities due to the spatial organization of individuals and traps. We adapt recently developed spatial capture–recapture models to estimate density and abundance of mountain lions in western Montana. Volunteers and state agency personnel collected mountain lion DNA samples in portions of the Blackfoot drainage (7,908 km2) in west-central Montana using 2 methods: snow back-tracking mountain lion tracks to collect hair samples and biopsy darting treed mountain lions to obtain tissue samples. Overall, we recorded 72 individual capture events, including captures both with and without tissue sample collection and hair samples resulting in the identification of 50 individual mountain lions (30 females, 19 males, and 1 unknown sex individual). We estimated lion densities from 8 models containing effects of distance, sex, and survey effort on detection probability. Our population density estimates ranged from a minimum of 3.7 mountain lions/100 km2 (95% CI 2.3–5.7) under the distance only model (including only an effect of distance on detection probability) to 6.7 (95% CI 3.1–11.0) under the full model (including effects of distance, sex, survey effort, and distance × sex on detection probability). These numbers translate to a total estimate of 293 mountain lions (95% CI 182–451) to 529 (95% CI 245–870) within the Blackfoot drainage. Results from the distance model are similar to previous estimates of 3.6 mountain lions/100 km2 for the study area; however, results from all other models indicated greater numbers of mountain lions. Our results indicate that unstructured spatial sampling combined with spatial capture–recapture analysis can be an effective method for estimating large carnivore densities. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.  相似文献   
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