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1.
Imbalance between proinflammatory and anti-inflammatory cytokines may regulate the inflammatory reaction in the nasal polyps. Polymorphisms in the regulatory regions of the cytokines genes may influence their expression. The aim of this study was to investigate the relationship between an IL- and IL-4 promoter polymorphisms and nasal polyps. The C-511T promoter polymorphism of the IL- gene and C-590T promoter polymorphism of the IL-4 gene were genotyped by polymerase chain reaction-restriction fragment length polymorphism analysis in 208 Polish patients with nasal polyps and 200 healthy Polish subjects. The risk of susceptibility to NP was significantly higher in patients with NP who had ?511 T/T genotype of IL1β than in controls (OR 3.07; 95 % CI 1.18–7.99). No statistically significant differences were found between NP patients and the control group with regard to genotype distribution and allele frequencies of C/T polymorphism of IL4 gene. Our study demonstrated that the TT genotype for C-511T mutation associated with the risk of developing NP in a Polish population.  相似文献   

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Anin vitro human nasal model was developed as a tool to study the local tolerabiliity of nasal powder forms using excised nasal mucosa in a diffusion chamber. The suitability of this model was tested using Sandostatin® (SMS) an octapeptide analog of somatostatin, as a reference drug enhanced by Avicel® (microcrystalline cellulose) or lactose (100 mesh). The standard nasal spray vehicle was taken as a harmless control and 1% chenodeoxycholate (CDC) as a harmful control in terms of local tolerability. The extent of peptide permeation was determined by measuring SMS concentration in the receiving chamber. The labeling of SMS was detected by immunoperoxidase staining on cross sections. The local tolerability for all tested forms was assessed by histopathological examination and scanning electron microscopy. The apparent permeation coefficient allowed us to rank the absorption of the tested drug forms as Avicel > spray=lactose>1%CDC. For all formulations, SMS was detected in the epithelium. No changes of the nasal mucosa could be observed with Avicel, lactose or nasal spray vehicle in the presence or absence of SMS. 1%CDC with or without drug showed an immediate destruction of the nasal epithelium. The validation of thisin vitro model using human nasal mucosa will be further discussed as a tool for assessing the local tolerability of intranasally applied test substances.Abbreviations CDC chenodeoxycholate - SMS Sandostatin® or octreotide  相似文献   

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Chen YH  Opp SB  Berlocher SH  Roderick GK 《Oecologia》2006,149(4):656-667
The success of invasive species appears to be a paradox: despite experiencing strong population bottlenecks, invasive species are able to successfully establish in new environments. We studied how the walnut husk fly, Rhagoletis completa, was able to successfully colonize California from the Midwestern United States, by examining genetic diversity and diapause variation of native and introduced fly populations. Climate plays an important role in the successful establishment of introduced insects, because insect diapause is highly dependent upon external climatic conditions. We examined if: (1) fly populations show signs of a population bottleneck, (2) native and introduced flies differ in diapause length when exposed to California and Midwestern climatic conditions, and (3) population genetic diversity is related to variation in diapause length. We assessed if fly diapause conformed more to a model of establishment by local adaptation or to a model of a highly plastic “general-purpose genotype”. Our results indicate that only two populations close to the original introduced location showed signs of a population bottleneck, and native and introduced populations did not differ in genetic diversity. Genetic diversity increased in the northern introduced populations, suggesting that multiple introductions have occurred. Flies emerged about 2 weeks earlier under the Midwestern treatment than the California treatment, and introduced flies emerged about a week earlier than native flies. All flies emerged when walnuts are typically available in California. Although variance in diapause length differed between populations, it did not vary between populations or regions. Furthermore, genetic diversity was not associated with diapause variation. Therefore, multiple introductions and a “general-purpose genotype” appear to have facilitated the fly’s invasion into California.  相似文献   

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The role of myosins in the pathogenesis of hearing loss is well established: five genes encoding unconventional myosins and two genes encoding nonmuscle conventional myosins have so far been described to be essential for normal auditory function and mutations in these genes associated with hearing impairment. To better understand the role of this gene family we performed a mutational screening on two candidate genes, MYO1C and MYO1F, analyzing hundreds of patients, affected by bilateral sensorineural hearing loss and coming from different European countries. This research activity led to the identification of 6 heterozygous missense mutations in MYO1C and additional 5 heterozygous missense mutations in MYO1F. Homology modelling suggests that some of these mutations could have a potential influence on the structure of the ATP binding site and could probably affect the ATPase activity or the actin binding process of both myosins. This study suggests a role of the above mentioned myosin genes in the pathogenesis of hearing loss.  相似文献   

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The relation between cholesterol concentration and mortality was studied prospectively over 17 years in 630 New Zealand Maoris aged 25-74. The dead or alive state of each person was determined in 1981. The causes of death were divided into three categories: cancer, cardiovascular disease, and "other." Using univariate and both linear and non-linear multivariate methods of analysis for survivorship data, significant inverse relations with serum cholesterol were found for total mortality in women, for mortality from cancer in men and women, and for other causes of mortality in both men and women. The inverse and non-linear association with total mortality in women remained significant when deaths in the first five years of follow up were excluded. This suggests that the association was not explained by undetected illness causing low cholesterol concentrations at the time of initial examination.  相似文献   

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Background

Sex steroids can positively affect the brain and from this it would follow that high levels of sex steroids could be associated with better cognitive function in older men and women.

Methods

This Healthy Ageing Study sample comprised of 521 older participants (51% women) without dementia at baseline, with an age range from 64 to 94 years. Testosterone and sex hormone binding globulin were measured using the automated Immulite 2000 and analyzed in association with baseline memory, global cognitive function and decline (assessed using the Mini-Mental Status Examination or MMSE) and controlling for potential confounds such as age, education, vascular disease, smoking, diabetes, thyroid function, and body mass index.

Results

In healthy older men and women, optimal levels of testosterone were associated with better MMSE scores at baseline. Follow-up analyses indicated that in men, low testosterone levels (OR = .94, 95% CI = .88 to 1.00) were a risk factor for a sharp cognitive decline after 2 years, perhaps indicative of dementia. Associations were independent of covariates and baseline MMSE. Conversely, women at risk for a sharp drop in cognitive function showed some evidence for higher calculated free testosterone levels at baseline.

Conclusions

Results replicate earlier cross-sectional findings that high levels of sex steroids are not associated with better cognitive function in older people. In men, age accelerated endocrinological change could be associated with dementia pathology.

General significance

These data do not support increasing testosterone levels to prevent cognitive decline in men and women over 65 years of age.  相似文献   

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Glycophorin prepared by a lithium di-iodosalicylate-extraction/phenol-partition method was rich in polyphosphoinositides (phosphatidyl-myo-inositol 4-phosphate and phosphatidyl-myo-inositol 4,5-bisphosphate), but glycophorin extracted by Triton X-100 showed no such enrichment. The enrichment observed in the former preparations appeared not to be caused by pre-existing association between glycophorin and polyphosphoinositides in the human erythrocyte membrane, but to be largely a consequence of the preparative procedures.  相似文献   

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Immune-dependent growth and development of infectious agents and pathogenesis of disease are increasingly being recognized. It is proposed that the development of filarial larvae to adult stage parasites takes place in an ambiance of inflammatory T helper cell type 1 cytokines in mammalian hosts, and that susceptibility to filarial infections could be governed by the status of macrophage-derived nitric oxide and host ability to produce antibodies to filarial T-independent (carbohydrate) antigens.  相似文献   

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Plant species abundance is partly determined by reproductive success and the factors that limit this success. We studied the flowering phenology, breeding systems and florivory in a community of seven epiphytic Tillandsia spp. in a tropical dry forest in central Mexico. Flowering periods were distributed throughout the year, and corolla sizes suggested that most species share pollinators. The most common breeding system was self‐incompatibility (Tillandsia achyrostachys, T. caput‐medusae and T. hubertiana), T. lydiae was infertile, T. circinnatioides was partially self‐compatible and T. recurvata and T. schiedeana were self‐compatible with high autonomous self‐pollination. Floral morphology suggests that delayed selfing occurs in the autonomous self‐pollinated species, and separation between stigma and stamens could result in self‐pollination in the remaining species being avoided. Less than 5% of the inflorescences in the most abundant species (T. recurvata) suffered damage by florivores, but > 40% of inflorescences were damaged in the other species. In damaged inflorescences, fruit set decreased by up to 89%. Our data show that the dominant species (T. recurvata) is autogamous and its reproductive success is slightly reduced by resource constraints and florivory. In the less abundant species, resource limitation and florivory dramatically reduced reproductive success, but the strength of these limiting factors is season dependent. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 50–65.  相似文献   

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Outbreaks of the Nilaparvata lugens (St?l), have occurred frequently in China during the past few years, resulting in a broad and significant reduction in rice yield. N. lugens immigrate into China each spring from Southeast Asia, and the Guangxi Zhuang Autonomous Region is the first area affected. Light trap catches for the early season period (March-June) in Guangxi for the past 30 yr have been analyzed, and the catch sequences for five observation stations (Longzhou, Hepu, Yongning Yongfu, and Quanzhou) were studied in detail. It was found that during the past 10 yr the first appearance of N. lugens at light traps occurs earlier, there is a higher frequency of days with large light-trap catches, and catches in southern Guangxi are larger. Recently light-trap catches have also increased in northern Guangxi. It is concluded that the increasing number of immigrants from overseas is one of the primary reasons for the increase in N. lugens outbreaks in the past 10 yr. Global warming, and specifically winter temperature increases, appears to be for a factor accelerating outbreaks of N. lugens in Asia.  相似文献   

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The activity of alpha 3-D-mannoside-beta-1,2-N-acetylglucosaminyltransferase I (GnT I; EC 2.4.1.101), which catalyzes the first step in the conversion of oligomannose to complex or hybrid N-glycans of glycoproteins, was detected in rat testicular and cauda epididymal fluids. The GnT I activity of testicular fluid had a pH optimum of 6.0, whereas that of the cauda epididymal fluid was optimal at pH 7.0. The enzyme in testicular fluid had an absolute requirement for either Co2+, or Mn2+, Mg2+ and Ca2+, the activity being stimulated by these cations in the above order, whereas that of cauda epididymal fluid had an absolute requirement for Mn2+ or Ca2+, with Co2+ and Mg2+ being ineffective. The specific activity of GnT I in cauda epididymal fluid was somewhat higher than in testicular fluid. The apparent Km value for alpha 1-3 alpha 1-6mannopentaose of GnT I in the testicular and epididymal fluids was 0.57 and 0.38 mM, respectively. The substrate specificity for both GnT I activities decreased in the following order: alpha1-3 alpha 1-6mannopentaose>alpha1-3 alpha 1-6mannotriose>alpha 1-3mannobiose>alpha 1-6mannobiose. These data suggest that two forms of GnT I exist in the testicular and epididymal fluids.  相似文献   

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