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991.
Population-based data on sexually transmitted infections (STI), bacterial vaginosis (BV), and candidiasis reflect the epidemiological situation more accurately than studies performed in specific populations, but such data are scarce. To determine the prevalence of STI, BV, and candidiasis among women of reproductive age from a resource-poor community in Northeast Brazil, a population-based cross sectional study was undertaken. All women from seven hamlets and the centre of Pacoti municipality in the state of Ceará, aged 12 to 49 years, were invited to participate. The women were asked about socio-demographic characteristics and genital symptoms, and thereafter examined gynaecologically. Laboratory testing included polymerase chain reaction (PCR) for human papillomavirus (HPV), ligase chain reaction (LCR) for Chlamydia trachomatis and Neisseria gonorrhoeae, ELISA for human immunodeficiency virus (HIV), venereal disease research laboratory (VDRL) and fluorescent treponema antibody absorption test (FTA-ABS) for syphilis, and analysis of wet mounts, gram stains and Pap smears for trichomoniasis, candidiasis, and BV. Only women who had initiated sexual life were included in the analysis (n = 592). The prevalences of STI were: HPV 11.7% (95% confidence interval: 9.3-14.7), chlamydia 4.5% (3.0-6.6), trichomoniasis 4.1% (2.7-6.1), gonorrhoea 1.2% (0.5-2.6), syphilis 0.2% (0.0-1.1), and HIV 0%. The prevalence of BV and candidiasis was 20% (16.9-23.6) and 12.5% (10.0-15.5), respectively. The most common gynaecological complaint was lower abdominal pain. STI are common in women in rural Brazil and represent an important health threat in view of the HIV pandemic.  相似文献   
992.
Duchenne muscular dystrophy (DMD) is a fatal and incurable muscle degenerative disorder. We identify a function of the protease urokinase plasminogen activator (uPA) in mdx mice, a mouse model of DMD. The expression of uPA is induced in mdx dystrophic muscle, and the genetic loss of uPA in mdx mice exacerbated muscle dystrophy and reduced muscular function. Bone marrow (BM) transplantation experiments revealed a critical function for BM-derived uPA in mdx muscle repair via three mechanisms: (1) by promoting the infiltration of BM-derived inflammatory cells; (2) by preventing the excessive deposition of fibrin; and (3) by promoting myoblast migration. Interestingly, genetic loss of the uPA receptor in mdx mice did not exacerbate muscular dystrophy in mdx mice, suggesting that uPA exerts its effects independently of its receptor. These findings underscore the importance of uPA in muscular dystrophy.  相似文献   
993.
This paper deals with apical dominance using a dicotylar model obtained after decapitation of pea seedlings with two shoots — one dominant and the other inhibited. When the dominant shoot was decapitated the inhibited one is released from inhibition and after 24 to 72 h begins to grow. However, the levels of trans-zeatin and production of ethylene increase within 4 and 6 hours respectively after release from inhibition, and within an interval of 72 h the levels of both phytohormones begin gradually to decrease. This indicates that also in this model, the release from apical dominance is associated with an increase in the level of cytokinin zeatin and, thereafter, also with an increased production of ethylene. If indolyl-3-acetic acid (IAA) is applied on the decapitated main stem after decapitation of the dominant shoot, the growth of the initially inhibited one is very strongly retarded; if, however, IAA is applied on the decapitated dominant shoot, this inhibition is significantly weaker. This means that the inhibiting effect of IAA on the inhibited shoot originates to a greater degree from the main stem rather than from the dominant shoot. The effect of benzyladenine (BA) is transferred equally from the decapitated main stem and from the decapitated dominant shoot because the initially inhibited shoot begins to grow as well as also other shoots from serial cotyledonary buds.  相似文献   
994.

Background  

The simultaneous production of various recombinant proteins in every cell of a culture is often needed for the production of virus-like particles (VLP) or vectors for gene therapy. A common approach for such a purpose is the coinfection of insect cell cultures with different recombinant baculoviruses, each containing one or more recombinant genes. However, scarce information exists regarding kinetics during multiple infections, and to our knowledge, no studies are available on the behavior of the different populations that arise during coinfections. Such information is useful for designing infection strategies that maximize VLP or vector yield. In this work, kinetics of cell populations expressing rotavirus GFPVP2 (infected with bacGFPVP2), VP6 (infected with bacVP6), or both proteins simultaneously (coinfected with both baculoviruses) were followed by flow cytometry.  相似文献   
995.

Background  

Core histone genes are periodically expressed along the cell cycle and peak during S phase. Core histone gene expression is deeply evolutionarily conserved from the yeast Saccharomyces cerevisiae to human.  相似文献   
996.
In 1949, Donald Hebb postulated that assemblies of synchronously activated neurons are the elementary units of information processing in the brain. Despite being one of the most influential theories in neuroscience, Hebb's cell assembly hypothesis only started to become testable in the past two decades due to technological advances. However, while the technology for the simultaneous recording of large neuronal populations undergoes fast development, there is still a paucity of analytical methods that can properly detect and track the activity of cell assemblies. Here we describe a principal component-based method that is able to (1) identify all cell assemblies present in the neuronal population investigated, (2) determine the number of neurons involved in ensemble activity, (3) specify the precise identity of the neurons pertaining to each cell assembly, and (4) unravel the time course of the individual activity of multiple assemblies. Application of the method to multielectrode recordings of awake and behaving rats revealed that assemblies detected in the cerebral cortex and hippocampus typically contain overlapping neurons. The results indicate that the PCA method presented here is able to properly detect, track and specify neuronal assemblies, irrespective of overlapping membership.  相似文献   
997.
Helicobacter pylori is considered one of the major risk factors underlying the development of gastritis and gastric and duodenal ulcers. Moreover, 50% of the population carries this bacterium, and consequently, when it is detected, eradication of H. pylori is strongly recommended. Regarding the use of probiotics as functional agents, several studies have shown that there is a direct relationship between the addition of certain probiotic bacteria and in vitro inhibition of H. pylori; however, in vivo studies showing bifidobacterial activity against H. pylori remain scarce. In this study, a Bifidobacterium bifidum strain which proved active in vitro against H. pylori has been isolated, with inhibition levels reaching 81.94% in the case of the supernatant and even 94.77% inhibition for supernatant purified by cationic exchange followed by an inverse phase. In vivo studies using a BALB/c mouse model have proved that this strain partially relieves damage to gastric tissues caused by the pathogen and also decreases the H. pylori pathogenicity ratio. This novel strain fulfills the main properties required of a probiotic (resistance to gastrointestinal juices, biliary salts, NaCl, and low pH; adhesion to intestinal mucus; and sensitivity to antibiotics). Furthermore, the absence of undesirable metabolites has been demonstrated, and its food safety status has been confirmed by acute ingestion studies in mice. In summary, the results presented here demonstrate that Bifidobacterium bifidum CECT 7366 can be considered a probiotic able to inhibit H. pylori both in vitro and in vivo.  相似文献   
998.
An important question asked by primatologists and conservationists alike is: what is the relevance of primates and primate conservation for ecosystem conservation? The goal of this article is to contribute to this dialogue by advocating the use of a research perspective that focuses on the dynamics of human-nonhuman primate sympatry and interaction (i.e., ethnoprimatology) in order to better understand complex social-ecological systems and to inform their conservation management. This perspective/approach is based largely on the recognition that human primates are important components of all ecological systems and that niche construction is a fundamental feature of their adaptive success. To demonstrate the relevance of the human-nonhuman primate interface for ecosystem conservation, we provide examples from our research from two islands in the Indonesian archipelago: Bali and Sulawesi. In Bali, humans and long-tail macaques coexist in a system that creates favorable environments for the macaques. This anthropogenic landscape and the economic and ecological relationships between humans and monkeys on Bali provide insight into sustainable systems of human/nonhuman primate coexistence. In Lore Lindu National Park in Central Sulawesi, villagers and Tonkean macaques overlap in their use of both forest and cultivated resources. The finding that the Arenga pinnata palm is extremely important for both villagers and macaques points to a conservation management recommendation that may help protect the overall ecosystem; the cultivation and propagation of mutually important tree species at forest-agricultural ecotone as a means to curb crop raiding and to alleviate farmer's perceived need to clear additional forest.  相似文献   
999.
Membrane proteins play key roles in diverse cellular functions and have become the target for a large number of pharmacological drugs. Despite representing about 20-30% of cellular proteins, their characterization is long overdue since they are difficult to handle, to purify from their natural source or to obtain as recombinant proteins. Pichia pastoris is a methylotrophic yeast species increasingly used as a host for heterologous protein expression for both research and industrial purposes. Over the past few years many efforts have allowed important advances in the development of this expression system for the expression and production of membrane proteins. The most recent achievements in improving yield and proper folding of integral membrane proteins are summarized in this review.  相似文献   
1000.
Proteins are the main reagents for structural, biomedical, and biotechnological studies; however, some important challenges remain concerning protein solubility and stability. Numerous strategies have been developed, with some success, to mitigate these challenges, but a universal strategy is still elusive. Currently, researchers face a plethora of alternatives for the expression of the target protein, which generates a great diversity of conditions to be evaluated. Among these, different promoter strength, diverse expression host and constructs, or special culture conditions have an important role in protein solubility. With the arrival of automated high-throughput screening (HTS) systems, the evaluation of hundreds of different conditions within reasonable cost and time limits is possible. This technology increases the chances to obtain the target protein in a pure, soluble, and stable state. This review focuses on some of the most commonly used strategies for the expression of recombinant proteins in the enterobacterium Escherichia coli, including the use of HTS for the production of soluble proteins.  相似文献   
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