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1.
R Banik  D Lubach 《Dermatologica》1987,174(4):180-183
The relevant literature does not contain detailed numerical data about skin tags. We found 46% skin tag carriers in 750 unselected persons (25% males and 21% females). The risk of getting skin tags increases with age. The age of 50, however, seems to be a turning point, at which a stagnation of the increase is observed. The majority of the carriers had no more than 3 tags per localization; the most frequent localization was the axilla, followed by the neck. This study supplies objective data for the evaluation of skin tags as markers for colonic polyps and may provide standard values for future studies.  相似文献   
2.
Eye infections caused by adenovirus (Ad) often result in nosocomial infections and community epidemics with significant rates of morbidity. No antiviral agent effective against Ad is yet available for clinical use. Therefore, early diagnosis is still the mainstay for patient management and the prevention of epidemics. A multiplex PCR assay based on amplification of a combination of the fiber and hexon genes which can identify the six important oculopathogenic serotypes of Ads (Ad serotype 3[Ad3], Ad4, Ad7, Ad8, Ad19, and Ad37) in a single-tube amplification reaction was developed. Ad serotypes could be distinguished by the different amplicon sizes. The assay correctly identified prototype strains as well as isolates in clinical specimens. In comparison with a previously described PCR-restriction fragment polymorphism method, our assay gave unequivocal results for clinical specimens. Our multiplex PCR has the potential to serve as a rapid and cost-effective tool for the typing of important ocular Ads.  相似文献   
3.
Nociceptors are excited or sensitized by many inflammatory mediators as well as by elevation of tissue temperature. We have shown that there is a facilitatory synergistic interaction between norepinephrine (NE) and bradykinin (BK) on cutaneous C-fiber nociceptors in normal Lewis rats. These interactions may play an important role in the mechanism of sympathetically maintained pain. In the present experiment, using skin-saphenous nerve in vitro preparations, we tested the effect of NE on the activity of nociceptive fibers and their response to heat in normal Sprague-Dawley rats. For comparison with the previous data on Lewis rats, we also examined the effect of NE on BK response. NE (10(-5) or 10(-6) M) did not excite nociceptive fibers before repeated heat stimuli or BK superfusion (10(-5) or 10(-6) M) to the receptive field. In contrast, after a few applications of heat or BK, NE excited 20-43% of nociceptive fibers to similar magnitudes. We also found that NE sensitized subsequent BK responses, but somewhat unexpectedly that it suppressed subsequent heat responses. This occurred regardless of the presence or absence of NE-induced excitation. These results suggest different mechanisms of NE modification to the BK and heat responses of cutaneous C-fiber nociceptors.  相似文献   
4.
We investigated whether there are any differences between the Lewis and Sprague-Dawley (SD) rats in chronic inflammation-induced norepinephrine (NE) sensitivity of nociceptors. Activities of C-fiber nociceptors innervating rat hairy hindpaw skin were recorded in an in vitro skin-nerve preparation. Sixty-five percent of C-fibers from inflamed Lewis rats were excited by NE (10 microM), against only 38% of C-fibers from inflamed SD rats. The average of the total impulses evoked in response to NE was also significantly higher in Lewis rats. The alpha2-adrenoceptor antagonist CH 38083 (10 microM) and yohimbine (10 microM) consistently blocked the NE-excitation of both strains. These results show that after chronic inflammation, C-fiber nociceptors of Lewis strain rats have a stronger sensitivity to NE, and that alpha2-adrenoceptors are predominately involved in the NE-sensitivity of inflamed rats in both strains.  相似文献   
5.
Pathophysiological role of calpain in experimental demyelination   总被引:3,自引:0,他引:3  
Calcium-activated neutral proteinase (calpain) has been extensively studied over the past three decades such that many enzymatic and structural properties of this enzyme are well understood. However, the pathophysiological roles of calpain remain poorly defined. In addition to recent studies delineating a role for calpain in various pathological conditions, this proteinase has been implicated in the degradation of myelin proteins in autoimmune demyelinating diseases such as multiple sclerosis and experimental allergic encephalomyelitis (EAE). In EAE, calpain translational expression is significantly increased in activated glial/inflammatory cells that participate in myelinolysis while calpain substrates (axonal and myelin proteins) are lost. Thus, since all major myelin proteins are calpain substrates, early studies suggest calpain may play an important role in demyelination of the central nervous system.  相似文献   
6.
Bradykinin (BK), an endogenous algesic and sensitizing substance, excited nociceptors and sensitized their heat responses. These effects were mediated by B2 receptors (B2Rs) in normal condition, and B1 receptors were additionally recruited in inflammation. B2Rs were coupled with Gq/11 and their activation resulted in diacylglycerol and inositol triphosphate release. Diacylglycerol activated protein kinase (PK) Cepsilon in sensory neurons. To clarify what channel was modulated by PKC to depolarize nociceptor terminals, we examined the heat activation threshold (Tt) of heat-sensitive capsaicin receptor (TRPV1). Tt was lowered down to 31 degrees C by BK in concentration dependent manner through activation of PKCepsilon in cells heterologously expressing TRPV1 and B2Rs. Thus both excitation and sensitization to heat could be explained by one mechanism, lowering Tt of TRPV1. The same was observed in capsaicin-sensitive primary sensory neurons. However, TRPV1 knockout mice showed almost no change in BK-induced nociceptive behavior and nociceptor excitation, although BK-induced heat hyperalgesia completely disappeared, suggesting that TRPV1 was not the sole channel that was modulated by BK to depolarize nociceptor terminals. In addition nociceptor sensitivity to BK was augmented in inflamed animals, with B2R mRNA and protein upregulated. The mechanism for prostaglandin-induced augmentation of BK response is left open for future study.  相似文献   
7.
This study was undertaken from 2009–2011 to understand the association between body mass index (BMI) and blood pressure (BP) (systolic or SBP and diastolic or DBP) among randomly chosen men, aged 30 to 59 years, of three endogamous communities in Darjeeling, West Bengal, India: Dhimal (n = 88), Mech (n = 71), and Rajbanshi (n = 83). Analysis of variance was applied. Remarkable rates of BMI-based undernutrition (chronic energy deficiency or CED) were recorded among Dhimals (31%) and Rajbanshis (18%). Notable prevalence of overweight (20%) was recorded among men of Mech community. None were found to be obese in three samples. Mean SBP and DBP were found to rise consistently at levels of BMI (undernutrition, normal, and overweight). BMI was observed to rise consistently at levels of blood pressures (normotensive, prehypertensive, and hypertensive). Among Mech, this pattern was found to be more conspicuous. DBP was found to be more sensitive with changes of BMI in men.  相似文献   
8.
Fusarium head blight (FHB) is one of the most important diseases of barley in Manitoba province (western Canada), and other major barley producing regions of the world. Little is known about the Fusarium species and mycotoxin spectra associated with FHB of barley in Manitoba. Hence, barley grain samples were collected from 149 commercial fields from 2017 to 2019, along with information on respective cropping history, and analyzed with respect to Fusarium species spectra, abundance, chemotype composition, and mycotoxin profiles. Fusarium poae was the predominant Fusarium species associated with FHB of barley in Manitoba, followed by F. graminearum, and F. sporotrichioides; F. equiseti and F. avenaceum were also detected but at low levels. F. poae strains with the nivalenol (NIV) chemotype and F. graminearum strains with 3-acetyl deoxynivalenol (3-ADON) and 15-acetyl deoxynivalenol (15-ADON) chemotypes were commonly detected in the barley grain samples. Nivalenol (597.7, 219.1, and 412.4 µg kg−1) and deoxynivalenol (DON) (264.7, 56.7, and 65.3 µg kg−1) were the two most prevalent mycotoxins contaminating Manitoba barley in 2017, 2018 and 2019, respectively. A substantially higher DON content was detected in grain samples from barley fields with cereals as a preceding crop compared to canola and flax. Furthermore, F. poae proved less sensitive to four triazole fungicides (metconazole, prothioconazole+tebuconazole, tebuconazole, and prothioconazole) than F. graminearum. Findings from this research will assist barley producers with improved understanding of FHB threat levels and optimizing practices for the best management of FHB in barley.  相似文献   
9.
Apoptosis of retinal ganglion cells (RGCs) impairs vision in glaucoma patients. RGCs are also degenerated in multiple sclerosis (MS), resulting in loss of visual perception in MS patients. We examined the involvement of calpain and caspase cascades in apoptosis of the rat retinal ganglion cell line RGC-5 following 24 h of exposure to 250 nM ionomycin (IMN) or 300 units/ml interferon-gamma (IFN-gamma) and then evaluated functional neuroprotection with 2 microM calpeptin (CP, a calpain-specific inhibitor). Morphological and biochemical features of apoptosis were detected in RGC-5 cells following exposure to IMN or IFN-gamma. Fura-2 assay determined significant increases in intracellular free [Ca2+] following exposure to IMN or IFN-gamma. Pretreatment with CP for 1 h prevented Ca2+ influx, proteolytic activities, and apoptosis in RGC-5 cells. Western blot analyses showed an increase in activities of calpain and caspase-12, upregulation of Bax:Bcl-2 ratio, release of cytochrome c from mitochondria, and increase in caspase-9 and caspase-3 activities during apoptosis. Increased caspase-3 activity was also confirmed by a colorimetric assay. Activation of caspase-8 and cleavage of Bid to tBid in RGC-5 cells following exposure to IFN-gamma indicated co-operation between extrinsic and intrinsic pathways of apoptosis. Patch-clamp recordings showed that pretreatment with CP attenuated apoptosis and maintained normal whole-cell membrane potential, indicating functional neuroprotection. Taken together, our results demonstrated that Ca2+ overload could be responsible for activation of calpain and caspase cascades leading to apoptotic death of RGC-5 cells and CP provided functional neuroprotection.  相似文献   
10.
Fluorescent pseudomonads are one of the most important microbial communities which play a key role in rhizosphere to enhance plant growth-promotion and protection. The diverse groups of antibiotics viz. 2,4-diacetylphloroglucinol (DAPG), phenazine-1-carboxylic acid (PCA) and pyoluteorin (PLT) are produced by fluorescent pseudomonads inhibiting growth of fungal pathogens which results in health upliftment of plants. The present study, discusses about frequency and diversity of 138 antibiotic-producing fluorescent pseudomonads isolated from eight genotypes of rapeseed mustard rhizosphere (Brassica juncea L. Czern.). The plant growth promoting traits and antibiotics (DAPG, PCA and PLT) production of isolates were examined by using polymerase chain reaction (PCR), thin layer chromatography (TLC) and dot blot-hybridization. Among 138 isolates, 47, 25 and 9 % of isolates were positive in indole production, phosphate solubilization and antagonism potential against Sclerotinia sclerotiorum (causal agent of white mold disease in rapeseed mustard), respectively. PCR amplifications showed that none of the isolates had phlD (DAPG) and phzC (PCA) genes, but four isolates (UKA-2, UKA-8, UKA-11, UKA-66) had pltB (PLT) gene, which was further confirmed by TLC and DNA dot-blot hybridization. BOX profiles of pltB positive isolates were distinct, showing unique genetic diversity in the small population. The four pltB positive fluorescent pseudomonad isolates could be used as promising bio-control and plant growth-promoting inoculants for Indian rapeseed mustard.  相似文献   
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