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991.
BACKGROUND: Hidradenitis suppurativa is a chronic inflammatory skin disease involving the axillary, inguinal and anogenital regions and sometimes, in addition, the submammary or sacral areas. The etiology of this condition is unknown. OBJECTIVE: A matched-pair case-control study was performed to evaluate the influence of smoking habits on the manifestation of this disease. METHODS: Patients who had received surgical treatment for hidradenitis suppurativa in two dermatological centers completed a questionnaire dealing with family history, course of the disease and smoking habits. To form a randomized matched-pair control group, an equal number of patients admitted for various other skin diseases such as atopic dermatitis, varicose veins, skin tattoos, alopecia areata or melanoma was matched for sex and age and evaluated for smoking habits. Statistical analysis was performed by use of several chi2 tests in a cross-table setting. Moreover, a comparison to the expected smoking prevalence in Germany based on national statistics was performed. RESULTS: Out of 84 patients treated for hidradenitis suppurativa, 63 subjects (27 men, 36 women) completed the questionnaire. The rate of active cigarette smokers was 88.9% (56 patients), whereas 4 subjects (6.4%) had never smoked. 3 patients (4.8%) stated to be ex-smokers, but 2 of these had quit smoking only recently and after onset of the disease. The rate of smokers in the matched-pair control group was 46%. The significantly higher proportion of active smokers among patients with hidradenitis suppurativa can be expressed by an odds ratio of 9.4, the calculated 95% confidence interval was 3.7-23.7 (p < 0.001). The expected smoking prevalence in Germany was 26.7% according to national statistics. 73% of our patients had no family history of hidradenitis suppurativa whereas 27% reported at least one affected first-degree relative. CONCLUSION: From the exceedingly high rate of smokers among patients with this condition we conclude that cigarette smoking is a major triggering factor of hidradenitis suppurativa. Remarkably, the disease can be categorized as a smoking sequel that is neither of vascular nor neoplastic nature. Because familial occurrence was rather rarely reported, and because an environmental factor in the form of cigarette smoking appears to be of crucial importance to trigger the disease, we assume that the genetic basis of hidradenitis suppurativa is polygenic rather than mendelian. Smoking cessation should be encouraged particularly in patients with hidradenitis suppurativa although it is unknown whether this improves the course of the disease. 相似文献
992.
Low resolution brain electromagnetic tomography (LORETA) functional imaging in acute, neuroleptic-naive, first-episode, productive schizophrenia 总被引:1,自引:0,他引:1
Roberto D. Pascual-Marqui Dietrich Lehmann Thomas Koenig Kieko Kochi Marco C. G. Merlo Daniel Hell Martha Koukkou 《Psychiatry Research: Neuroimaging》1999,90(3):442-179
Functional imaging of brain electrical activity was performed in nine acute, neuroleptic-naive, first-episode, productive patients with schizophrenia and 36 control subjects. Low-resolution electromagnetic tomography (LORETA, three-dimensional images of cortical current density) was computed from 19-channel of electroencephalographic (EEG) activity obtained under resting conditions, separately for the different EEG frequencies. Three patterns of activity were evident in the patients: (1) an anterior, near-bilateral excess of delta frequency activity; (2) an anterior-inferior deficit of theta frequency activity coupled with an anterior-inferior left-sided deficit of alpha-1 and alpha-2 frequency activity; and (3) a posterior-superior right-sided excess of beta-1, beta-2 and beta-3 frequency activity. Patients showed deviations from normal brain activity as evidenced by LORETA along an anterior-left-to-posterior-right spatial axis. The high temporal resolution of EEG makes it possible to specify the deviations not only as excess or deficit, but also as inhibitory, normal and excitatory. The patients showed a dis-coordinated brain functional state consisting of inhibited prefrontal/frontal areas and simultaneously overexcited right parietal areas, while left anterior, left temporal and left central areas lacked normal routine activity. Since all information processing is brain-state dependent, this dis-coordinated state must result in inadequate treatment of (externally or internally generated) information. 相似文献
993.
Controlled reperfusion of ischemic extremity musculature to prevent free radical induced lesions] 总被引:1,自引:0,他引:1
B Luther C Lehmann T Grune R Meyer G Schwenke H Beutel K Bürger 《Zentralblatt für Chirurgie》1999,124(4):336-343
Tissue injury following reperfusion represents an essential problem of reconstructive vascular surgery. Pathogenetically toxic oxygen radicals are considered to play a pivotal role. Pharmacotherapeutical approaches are based particularly on antioxidants and vasodilators. However, a standardized regimen is not yet clinically introduced. In 48 adult Lewis-rats lower limb ischemia was induced by aortal cross-clamping. Following 3.5 hours of ischemia intravascular flushing perfusion via the distal aorta with a heparinized electrolyte solution (group B). Group C received additionally oxypurinol, group D alprostadil and group E sodium selenite into the flushing solution. At 4 hours recirculation was established. After 10 min, 30 min and 24 hours of reperfusion we determined lactate, creatine kinase, lactate dehydrogenase, urea, malondialdehyde and the laser Doppler flux. At the end of the experiments biopsies were taken from M. tibialis anterior. In comparison to control animals (group A) we observed an attenuation of reperfusion injury in the groups treated with flushing perfusion. Free oxygen radical reactions measured by malondialdehyde release were significantly reduced (30 min: A-209.1 +/- 45.4, B-127.3 +/- 36.9, C-113.2 +/- 14.1, D-99.6 +/- 24.5, E-123.6 +/- 11.2 mmol/l, p < 0.05). The laser Doppler flux measurements corresponded with the biochemical analyses (30 min: A-52.4 +/- 11.1, B-48.0 +/- 11.0, C-72.6 +/- 12.0, D-74.4 +/- 13.3, E-62.6 +/- 10.8% of baseline). Histologically, treatment with alprostadil (PGE1) and oxypurinol revealed superior results. Standardized intraarterial flushing perfusion with antioxidants and vasodilators reduces reperfusion injury. Clinical trials are urgently required to confirm the experimental findings and to optimize the therapy of extremity ischemia/reperfusion injury in humans. 相似文献
994.
Isolation and characterization of microcystins from a river nile strain of Oscillatoria tenuis Agardh ex Gomont. 总被引:7,自引:0,他引:7
S. Brittain Z. A. Mohamed J. Wang V. K. B. Lehmann W. W. Carmichael K. L. Rinehart 《Toxicon》2000,38(12):1759-1771
The River Nile is the major source of drinking water in Egypt, however, increased eutrophication due to agricultural, municipal and industrial runoff has contributed to the growth of toxin producing cyanobacteria. This study describes the isolation and characterization of microcystins (MCYSTs), cyclic heptapeptide hepatotoxins, from a rare strain of Oscillatoria tenuis, isolated from the River Nile at Sohag province in July 1995. The MCYST concentration of laboratory-cultured O. tenuis strain E6 was found to be 0.3 mg/g freeze-dried weight determined by enzyme-linked immunosorbent assay (ELISA). Two microcystins, 1 and 2, were isolated from lyophilized cells using solid phase extraction and reversed-phase high performance liquid chromatography (HPLC). Structures were assigned based upon their amino acid analyses, electrospray ionization mass spectrometry (ESIMS, ESIMS-CID-MS), high resolution fast atom bombardment mass spectrometry, and nuclear magnetic resonance data (1H and 1H COSY NMR). Toxin 1 was identified as MCYST-LR, and toxin 2, a new MCYST, as MCYST-LHArg ([
-homoarginine4]). Previous studies indicate that Oscillatoria agardhii strains produce demethylated MCYSTs (containing
-Asp and/or dehydroalanine). This is the first report of a toxic O. tenuis, strain E6, one which produces a fully methylated MCYST, MCYST-LR and a new
-homoarginine containing MCYST, MCYST-LHArg. 相似文献
995.
Alterations of Glial Cell Function in Temporal Lobe Epilepsy 总被引:4,自引:1,他引:3
U. Heinemann S. Gabriel R. Jauch K. Schulze A. Kivi A. Eilers R. Kovacs T.-N. Lehmann 《Epilepsia》2000,41(S6):S185-S189
Summary: Purpose : Comparison of extracellular K+ regulation in sclerotic and nonsclerotic epileptic hippocampus.
Methods : Measurements of K+ signals with double-barreled K+ -selective reference microelectrodes in area CA1 of slices from human and rat hippocampus, induction of increases in extracellular potassium concentration by repetitive alvear stimulation or iontophoresis, and block of inward-rectifying and background K+ channels in astrocytes by barium.
Results : In the CA1 pyramidal layer from normal rat hippocampus, barium augmented extracellular K+ accumulation induced by iontophoresis or antidromic stimulation in a dose-dependent manner. Similarly, barium augmented stimulusinduced K+ signals from nonsclerotic hippocampi (human mesial temporal lobe epilepsy). In contrast, barium failed to do so in sclerotic hippocampi (human mesial temporal lobe epilepsy, rat pilocarpine model).
Conclusions : Our findings suggest that in areas of reduced neuronal density (hippocampal sclerosis), glial cells adapt to permit rather large increases in extracellular potassium accumulation. Such increases might be involved in the transmission of activity through the sclerotic area. 相似文献
Methods : Measurements of K
Results : In the CA1 pyramidal layer from normal rat hippocampus, barium augmented extracellular K
Conclusions : Our findings suggest that in areas of reduced neuronal density (hippocampal sclerosis), glial cells adapt to permit rather large increases in extracellular potassium accumulation. Such increases might be involved in the transmission of activity through the sclerotic area. 相似文献
996.
树突状细胞与肝脏疾病 总被引:9,自引:3,他引:6
免疫反应的产生首先是由抗原提呈细胞(antigenpresenting cells,APC)捕获抗原,经其加工处理后将抗原信息传递给T,B淋巴细胞,从而引发一系列的特异性免疫应答.APC包括树突状细胞(dendritic cells,DC)、巨噬细胞(MΦ)、B细胞等,其中DC是人体内最具潜能的抗原提呈细胞(APC),能在体内外直接激活纯真(naive)T细胞,提呈抗原给MHC-Ⅰ类限制性CD8+和MHC-Ⅱ类限制性CD4+T淋巴细胞,诱导特异性免疫应答[1-6]. 相似文献
997.
Several lines of evidence indicate a critical role of the piriform cortex (PC) in the kindling model of temporal lobe epilepsy, suggesting that the PC is part of an epileptic network that is pivotal in the genesis of kindling, facilitating, and intensifying the spread of seizures from a focus in amygdala, hippocampus, or other limbic brain regions to cortical and subcortical regions. Kindling of the amygdala has been shown to induce long-lasting changes in synaptic efficacy in the ipsilateral PC comparable to abnormalities seen in epileptic foci, but the neurochemical alterations possibly underlying these functional changes are not known. The possibility that the enhanced excitability of the PC in response to kindling is related to a reduction of GABAergic neurotransmission prompted us to examine if a lasting reduction in GABA-immunoreactive PC neurons is detectable after kindling of the basolateral amygdala (BLA) in rats. Furthermore, GABA immunoreactivity was determined in the BLA in order to investigate whether GABAergic neurons decrease in focal tissue, as previously suggested by neurochemical and immunocytochemical studies in amygdala-kindled rats. Three groups of age-matched rats were used: (1) a group of rats that was kindled via electrical stimulation by a bipolar electrode implanted in the right BLA, (2) a group of BLA-implanted but nonstimulated rats, and (3) a group of non-implanted, naive control rats. The kindled rats were sacrificed 40 days after the last fully kindled seizure. The two other groups of rats were sacrificed together with the kindled rats on the same days, and tissues from kindled and control rats were treated concurrently throughout the immunohistochemical analysis. GABA neurons were stained by a monoclonal antibody to GABA. Kindling of the BLA led to a pronounced decrease in the number of GABA immunoreactive neurons in the ipsi- and contralateral BLA at all section levels examined. In the PC, no significant differences between groups were seen in the contralateral hemisphere, while a significant reduction in GABA immunoreactive cells was observed in the transition zone between anterior and posterior PC in the hemisphere ipsilateral to the BLA electrode. The present findings add to the accumulating evidence that the PC is critically involved in kindling-induced epileptogenesis. The data furthermore substantiate that the PC is not a homogeneous structure but that there are differences along the anterior-posterior axis of this region in neurochemical (and most certainly also functional) consequences in response to kindling stimulation from other limbic brain regions. Synapse 29:299–309, 1998. © 1998 Wiley-Liss, Inc. 相似文献
998.
999.
Uniaxially drawn syndiotactic polystyrene (sPS) in various modifications has been analyzed by static difference polarization spectra and DIRLD (dynamic infrared linear dichroism) spectra during mechanical stretching. Both, derivative bipolar bands and monopolar bands, are observed as a hint to submolecular changes induced by the applied external strain. The lineshape features in the dynamic in-phase spectra are described on the basis of frequency shifts and absorption amplitude variations during the stretching cycle. The conformationally sensitive vibrational modes are most sensitive to the external perturbation. The different responses of the conformationally insensitive vibrational modes to the external perturbation are discussed. 相似文献
1000.
Annegret Buske Andreas Gewies Rüdiger Lehmann Klaus Rüther Bernd Algermissen Peter Nürnberg Sigrid Tinschert 《American journal of medical genetics. Part A》1999,86(4):328-330
We report a 21-year-old male with symptomatic optic glioma who does not fulfill the diagnosis of neurofibromatosis 1 (NF1) according to standard NIH criteria. Analysis of the NF1 gene revealed a recurrent mutation in exon 37 (C6792A or Y2264X). This nonsense mutation causes skipping of exon 37 during the splicing process and is predicted to result in a protein shortened by 34 amino acid residues. The mutation was detected in all tissues examined (blood lymphocytes, oral mucosa, and dermal fibroblasts). The same mutation was previously found in 3 patients with clinically confirmed NF1. To our knowledge, this is the first report of an adult patient carrying a putative (non-mosaic) NF1 gene mutation in multiple tissues but not fulfilling the NIH criteria for the clinical diagnosis of NF1. Am. J. Med. Genet. 86:328–330, 1999. 相似文献