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991.
Owl pellets have long been used to analyze communities of small mammals, while analogous analyses of faeces of mammal carnivores are not available. We demonstrate that common genet (Genetta genetta) scats can be used as a reliable method to sample small mammal communities and to monitor their variations. We have compiled data on 6350 small mammal remains of 18 species found in scats from 51 different latrines in a 1200 km2 area of northeastern Spain. Genet scats sampled effectively 95.6% of the small mammal species ranging in size from 2.7 to 385 g. Spatial patterns of diet composition along environmental gradients of elevation, climate and land-use matched expected changes in small mammal communities along these gradients according to ecological requirements of prey species. Frequencies of occurrence of prey in genet scats were strongly correlated with frequencies of occurrence in barn owl (Tyto alba) pellets. Genet scats included two forest species not preyed upon by owls, whereas only one species was not preyed upon by genets. Forests species were more frequent in genet than in barn owl diets after correcting for environmental effects, whereas the opposite was true for open-habitat and synanthropic species. Scats of generalist carnivores can be used to estimate the spatial patterns of distribution and abundance of small mammal communities. Genet scats in fact overcome some of the limitations of more traditional sampling methods (live-trapping and owl diets), as genets were less selective and their diets reflect more accurately changes in community composition.  相似文献   
992.
993.
Anticholinergics, specifically antimuscarinic agents, are the most common medications prescribed for overactive bladder (OAB). The most common side effects of these agents are dry mouth and constipation, although other more concerning effects include changes in blood pressure, pulse rate, or heart rhythm when treatment is initiated. Herbal treatments are an increasingly popular alternative for treating OAB. A 2002 survey of US adults aged ≥ 18 years conducted by the Centers for Disease Control and Prevention indicated that 74.6% of those with OAB had used some form of complementary and alternative medicine. The World Health Organization estimates that 80% of the world’s population presently uses herbal medicine for some aspect of primary health care. Women were more likely than men to use complementary and alternative medicine. The authors review the most commonly used herbal medications for OAB.Key words: Overactive bladder, Herbal medicine, Gosha-jinki-gan, Hachi-mi-jio-gan, Buchu (Barosma betuline), Cleavers (Galium aparine), Cornsilk (Zea mays), Horsetail (Equisetum), Ganoderma lucidum, Resinferatoxin, CapsaicinOveractive bladder (OAB) is defined by the International Continence Society as a syndrome that includes urgency, with or without urge incontinence, frequency, and nocturia. The prevalence of OAB is estimated to range between 9% and 16%, depending on the population studied.13 As symptoms of OAB increase with age, they can negatively impact quality of life (QoL).The cost of treating OAB is estimated to be approximately $12 billion annually in the United States.4 This estimate accounts for the direct cost of management, including protective undergarments, bedside commodes, and medical treatment, as well as indirect costs, such as those resulting from urinary tract infections and falls due to urgency and nocturia. There are also additional intangible costs that cannot be estimated such as pain, suffering, and poor QoL.The negative impact on health and the sense of well-being as well as the impairment in the ability to perform activities of daily living, has been well-documented. For example, elderly patients with OAB and subsequent incontinence are more likely to be admitted to nursing homes. Thom and colleagues reported a twofold increased risk of admission to a nursing facility for patients with incontinence.5 Urinary incontinence can also lead to anxiety, negative self-image, and isolation.4 Other problems associated with OAB include skin ulcerations and urinary tract infections. Nocturia is common with OAB and ranks among the most bothersome of lower urinary tract symptoms.6 In addition to sleep interruption and resulting fatigue, patients with nocturia may be more likely to suffer from falls and fractures, which are associated with high mortality in elderly patients. Approximately 33% of elderly people do not survive beyond 1 year after a hip fracture.7The impact of OAB was clearly reported in the National Overactive Bladder Evaluation (NOBLE) study.8 The NOBLE study represented a computer-assisted telephone interview survey that used health-related QoL (HRQoL) questionnaires to compare continent OAB patients, with incontinent OAB patients, and control groups in a nested case-control fashion. In this study, OAB was associated with lower QoL scores, higher scores on depression, and poorer sleep quality when compared with control subjects.8 Note that, although the prevalence of OAB increases with age, it should not be considered a normal consequence of aging.Anticholinergics, specifically antimuscarinic agents, represent the most common medications prescribed for OAB. The most common side effects are dry mouth and constipation.9,10 Other more concerning side effects include changes in blood pressure, pulse rate, or heart rhythm when treatment is initiated. Additional adverse events (AEs) include memory loss, cognitive impairment, and balance problems. Thus, alternative therapies not involving standard medications and their associated risks are sought by patients to alleviate symptoms of OAB.Herbal treatments represent an increasingly popular alternative for treating OAB. A 2002 survey of US adults aged ≥ 18 years conducted by the Centers for Disease Control and Prevention indicated 74.6% of those with OAB had used some form of complementary and alternative medicine. The World Health Organization estimates that 80% of the world’s population presently uses herbal medicine for some aspect of primary health care. Women were more likely than men to use complementary and alternative medicine.10,11 We review the most commonly used herbal medications used for OAB.  相似文献   
994.
995.
Integration of the HIV-1 cDNA into the human genome is catalyzed by the viral integrase (IN) protein. Several studies have shown the importance of cellular cofactors that interact with integrase and affect viral integration and infectivity. In this study, we produced a stable complex between HIV-1 integrase, viral U5 DNA, the cellular cofactor LEDGF/p75 and the integrase binding domain of INI1 (INI1-IBD), a subunit of the SWI/SNF chromatin remodeling factor. The stoichiometry of the IN/LEDGF/INI1-IBD/DNA complex components was found to be 4/2/2/2 by mass spectrometry and Fluorescence Correlation Spectroscopy. Functional assays showed that INI1-IBD inhibits the 3′ processing reaction but does not interfere with specific viral DNA binding. Integration assays demonstrate that INI1-IBD decreases the amount of integration events but inhibits by-product formation such as donor/donor or linear full site integration molecules. Cryo-electron microscopy locates INI1-IBD within the cellular DNA binding site of the IN/LEDGF complex, constraining the highly flexible integrase in a stable conformation. Taken together, our results suggest that INI1 could stabilize the PIC in the host cell, by maintaining integrase in a stable constrained conformation which prevents non-specific interactions and auto integration on the route to its integration site within nucleosomes, while LEDGF organizes and stabilizes an active integrase tetramer suitable for specific vDNA integration. Moreover, our results provide the basis for a novel type of integrase inhibitor (conformational inhibitor) representing a potential new strategy for use in human therapy.  相似文献   
996.
Recent evidence suggests that transient hyperglycemia in extremely low birth weight infants is strongly associated with the occurrence of retinopathy of prematurity (ROP). We propose a new model of Neonatal Hyperglycemia-induced Retinopathy (NHIR) that mimics many aspects of retinopathy of prematurity. Hyperglycemia was induced in newborn rat pups by injection of streptozocine (STZ) at post natal day one (P1). At various time points, animals were assessed for vascular abnormalities, neuronal cell death and accumulation and activation of microglial cells. We here report that streptozotocin induced a rapid and sustained increase of glycemia from P2/3 to P6 without affecting rat pups gain weight or necessitating insulin treatment. Retinal vascular area was significantly reduced in P6 hyperglycemic animals compared to control animals. Hyperglycemia was associated with (i) CCL2 chemokine induction at P6, (ii) a significant recruitment of inflammatory macrophages and an increase in total number of Iba+ macrophages/microglia cells in the inner nuclear layer (INL), and (iii) excessive apoptosis in the INL. NHIR thereby reproduces several aspects of ischemic retinopathies, including ROP and diabetic retinopathies, and might be a useful model to decipher hyperglycemia-induced cellular and molecular mechanisms in the small rodent.  相似文献   
997.

Introduction

During summer 2010, 262 human cases including 35 deaths from West Nile virus (WNV) infection were reported from Central Macedonia, Greece. Evidence from mosquitoes, birds and blood donors demonstrated that the epidemic was caused by WNV lineage 2, which until recently was considered of low virulence. We conducted a household seroprevalence study to estimate the spread of infection in the population during the epidemic, ascertain the relationship of infection to clinical disease, and identify risk factors for infection.

Methods

We used a two-stage cluster design to select a random sample of residents aged ≥18 years in the outbreak epicentre. We collected demographic, medical, and risk factor data using standard questionnaires and environmental checklists, and tested serum samples for presence of WNV IgG and IgM antibodies using ELISA.

Results

Overall, 723 individuals participated in the study, and 644 blood samples were available. Weighted seropositivity for IgG antibodies was 5.8% (95% CI: 3.8–8.6; n=41). We estimated that about 1 in 130 (1:141 to 1:124) infected individuals developed WNV neuroinvasive disease, and approximately 18% had clinical manifestations attributable to their infection. Risk factors for infection reflected high exposure to mosquitoes; rural residents were particularly at risk (prevalence ratio: 8.2, 95% CI: 1.1–58.7).

Discussion

This study adds to the evidence that WNV lineage 2 strains can cause significant illness, demonstrating ratios of infection to clinical disease similar to those found previously for WNV lineage 1.  相似文献   
998.
999.
Ixodes scapularis is the specific arthropod vector for a number of globally prevalent infections, including Lyme disease caused by the bacterium Borrelia burgdorferi. A feeding-induced and acellular epithelial barrier, known as the peritrophic membrane (PM) is detectable in I. scapularis. However, whether or how the PM influences the persistence of major tick-borne pathogens, such as B. burgdorferi, remains largely unknown. Mass spectrometry-based proteome analyses of isolated PM from fed ticks revealed that the membrane contains a few detectable proteins, including a predominant and immunogenic 60 kDa protein with homology to arthropod chitin deacetylase (CDA), herein termed I. scapularis CDA-like protein or IsCDA. Although IsCDA is primarily expressed in the gut and induced early during tick feeding, its silencing via RNA interference failed to influence either the occurrence of the PM or spirochete persistence, suggesting a redundant role of IsCDA in tick biology and host-pathogen interaction. However, treatment of ticks with antibodies against IsCDA, one of the most predominant protein components of PM, affected B. burgdorferi survival, significantly augmenting pathogen levels within ticks but without influencing the levels of total gut bacteria. These studies suggested a preferential role of tick PM in limiting persistence of B. burgdorferi within the vector. Further understanding of the mechanisms by which vector components contribute to pathogen survival may help the development of new strategies to interfere with the infection.  相似文献   
1000.
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