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11.
BACKGROUND: A change in neural responsiveness may occur as the result of allergic inflammation in the lower airways as well as in the upper airways. In the lower airways, capsaicin cough sensitivity is known to reflect sensory neural reactivity. OBJECTIVE: The aim of this study was to establish whether allergic inflammation changes airway neural sensory reactivity during prolonged allergen exposure. METHODS: Ten nonsmoking patients with birch pollen-allergic asthma performed a capsaicin inhalation challenge twice, once in the off-pollen season and once during the pollen season. The number of coughs and symptoms induced by capsaicin were recorded and compared with those of healthy control subjects. RESULTS: The response to capsaicin, expressed as number of coughs, increased in a dose-dependent manner during both tests. Before the season, the response was similar to that of healthy control subjects, but during the pollen season, the reactivity was significantly increased. Variations in forced expiratory volume in 1 second were not significant before and after each challenge, and values did not change during the pollen season as compared with the winter season. CONCLUSIONS: Sensory reactivity in allergic asthmatic patients may be increased during prolonged allergen exposure as during the pollen season. This finding suggests that allergic inflammation in the lower and/or upper airways may trigger neurogenic mechanisms of significant clinical importance.  相似文献   
12.
Summary: In this study, the administration of erythropoietin to haemodialysis patients revealed its immunomodulating properties. to dissociate the immunological effects of erythropoietin action from its haematological effects the patients in our study were administered recombinant human erythropoietin (rhEpo) at the doses that would not affect erythropoiesis. After baseline data had been obtained, six haemodialysis patients were given rhEpo (Eprex-Cilag) at the dose 7-10 U/kg bodyweight/s.c., three times a week, for 12 weeks. All patients maintained a stable haemoglobin concentration; no blood transfusions were required. Serum levels of tumour necrosis factor (TNF), IL-2 and IL-6 levels of the study patients and the four control patients, not receiving rhEpo, were monitored every 2 weeks. the levels of IL-6 and TNF remained unchanged; however, a low serum level of IL-2, recorded before therapy, increased gradually for 10 weeks until it reached the values observed in normal healthy humans (P<0.01). After that it dropped to the initial values. During the study the red blood cell numbers did not change. This study supports the thesis that erythropoietin administered to haemodialysis patients not only corrects anaemia but also independently modulates immunological response.  相似文献   
13.
Chronic/relapsing experimental allergic encephalomyelitis (CREAE) serves as an animal model for relapsing/remitting multiple sclerosis. Treatment with the β-adrenergic agonist isoproterenol or the β2-adrenergic agonist terbutaline significantly suppressed both the first acute attack and the number of relapses in CREAE Lewis rats. The number of relapses was decreased even when treatment with β-adrenergic agonist was started after the onset of the first acute attack of CREAE. β-adrenergic receptor number was increased significantly on splenocytes from CREAE rats as compared to healthy controls or CFA-injected rats. Terbutaline treatment of CREAE rats lowered the splenocyte receptor number to normal values.  相似文献   
14.
We report on a case of Prader-Willi syndrome (PWS) with a true reciprocal unbalanced translocation, 45,XX,-15,der(11)t(11;15)pat. The proposita was diagnosed clinically as having severe PWS. Molecular studies revealed loss of the paternal methylation pattern at locus D15S63 and a deletion encompassing the loci from at least D15S10 to D15S97 of paternal chromosome 15. FISH studies confirmed the deletion of 15q11-q13 region and the presence of two telomeres on all chromosomes. The proposita's father, the father's sister and their mother are all carriers of the same balanced translocation t(11;15)(q25;q13). By genomic imprinting we would expect that if the father's sister were to give birth to a child with the same unbalanced translocation as the proband, it would be affected by Angelman syndrome.
To date, a similar familial unbalanced translocation due to loss of the small chromosome 15 derivative has not been described.  相似文献   
15.
Deregulated cell cycle and defective genome-integrity checkpoints are among the hallmarks of cancer.Here we summarize our recent studies of key components of the GI/S machinery in normal human spermatogenesis, and their abnormalities in testicular germ cell tumours (TGCTs), with special emphasis on carcinoma in situ lesions (CIS). Our combined immunohistochemical and immunoblotting analyses of normal human adult and fetal testes, CIS, seminomas, embryonal carcinomas, and teratomas, revealed an 'unorthodox' spectrum of defects within the so-called RB pathway in TGCTs. The early aberrations included lack of expression of the retinoblastoma tumour suppressor (pRB) and the CDK inhibitor pl9ink4d, and overexpression of cyclin D2. Progression from CIS to invasive TGCTswas associated with loss of another two CDK inhibitors and tumour suppressors: pl6ink4a and pl8ink4c. We also found the lack of pRB and pl9ink4d in fetal gonocytes, the candidate target cell for all types of TGCTs. These findings, together with the status of the Chk2-p53 DNA-integrity checkpoint, are considered in relation to the origin, biology and pathogenesis of TGCTs, and potential implications of the GI/S defects for the curability of these tumours.  相似文献   
16.
BACKGROUND: Aspirin-induced asthma/rhinitis (AIAR) is characterized by the altered metabolism of leukotrienes and proinflammatory prostaglandins. The basal and postchallenge levels of eicosanoids might reflect the clinical and biochemical characteristics of patients with distinct types of hypersensitive responses to aspirin. OBJECTIVE: We compared clinical and eicosanoid profiles of patients with AIAR showing both bronchial and nasal versus isolated nasal responses to aspirin challenge. METHODS: Twenty-three patients with AIAR underwent the single-blind, oral, placebo-controlled aspirin challenge. The bronchial response (BR) was evidenced by dyspnea and spirometry, whereas the nasal response (NR) was evidenced by nasal symptoms and acoustic rhinometry and/or rhinomanometry. Urinary leukotriene E4 (uLTE4), serum and urinary stable prostaglandin D2 metabolite, and 9alpha,11beta-prostaglandin F2 (9alpha,11beta-PGF2), were determined at baseline and after the aspirin challenge. RESULTS: Fifteen subjects showed BR and NR (BNR), whereas 8 showed NR only. Basal uLTE4 in the BNR group was significantly higher than in the NR group. After aspirin challenge, it increased significantly in both groups. Serum 9alpha,11beta-PGF2 increased after aspirin challenge in the BNR group only. The patients with BNR had more severe AIAR. CONCLUSIONS: BNR to aspirin in AIAR indicates a more advanced disease and more profound underlying eicosanoid metabolism disturbances.  相似文献   
17.
The purpose of this study was comparison of VEGF (vascular endothelial growth factor) levels in serum and pleural fluid and estimation of this test usefulness in diagnosis of pleural effusions. VEGF levels were measured by ELISA method in 68 patients (45 males and 23 females) aged 19-81 years. By Light's criteria in 16 cases transudate and in 52 cases exudate was recognized. By means of fluid cytology, pleural biopsy, microbiology or thoracoscopy in 10 cases pleural metastases from distant organs, in 15 cases coexisting pulmonary neoplasm, in 11 cases mesothelioma and in 16 cases tuberculosis were determined as a cause of fluid accumulation in pleural space. The mean VEGF levels were significantly higher (p < 0.001) in patients with exudates than in patients with transudates (3833 pg/ml and 325 pg/ml respectively). Based on likelihood ratios analysis, as a cut off value in differentiation of exudates and transudates a value 700 pg/ml was accepted. The sensitivity of this test was 75% and the specificity 93% and likelihood ratio (LR) 12.5. The mean VEGF level in exudates was seven times higher than mean VEGF level in serum (3833 pg/ml and 573 pg/ml respectively). Mean VEGF levels in malignant exudates (4615 pg/ml) were significantly higher than in tuberculous exudates (2073 pg/ml). As a cut off value in differentiation between malignant and tuberculous exudates a value of 4500 pg/ml was accepted. We conclude that our results suggests the local VEGF production in pleural cavity and the significant role of this cytokine in pleural exudates accumulations and also suggests the usefulness of VEGF estimation in pleural fluid in differentiation transudates from exudates and malignant from tuberculous pleural fluids.  相似文献   
18.
Human mitochondrial diseases are usually caused by dysfunction of mitochondrial DNA (mtDNA), particularly by point mutations, deletions, or depletions. In commonly used procedures for molecular diagnostics of mitochondrial dysfunction, one of the first steps is linearization of circular mitochondrial genomes with either BamHI or PvuII restriction endonulease, which cuts human mtDNA at a unique site. Here, we describe a case of false positive results, which suggested mtDNA depletion or a large deletion in a patient's tissue sample. More detailed analysis (mtDNA sequencing) revealed that these false positive results were caused by the presence of the 12753A>G substitution in the gene coding for NADH dehydrogenase subunit 5 (ND5). This substitution results in no change in amino acid sequence of the gene product but creates an additional PvuII site. Investigating a population of 200 patients not affected by mitochondrial diseases, we found an additional case of 12753A>G, and also another substitution, 12804T>C, which also results in no change in amino acid sequence of ND5 but creates an additional PvuII site. A few cases of 12753A>G and 12804T>C substitutions were found previously in Asian, American, African, and European populations (though they were not reported to date in the MITOMAP), but those samples were used in population studies and not tested for mtDNA deletion or depletion. Therefore, we present a cautionary report indicating that these mtDNA polymorphisms exist in various human populations (and thus, they are panethnic) and may cause false positive results of standard molecular analyses, including molecular diagnostics, of human mtDNA.  相似文献   
19.
Three patients with Alzheimer's disease, a 68-year-old woman with mild dementia and 2 men (aged 64 and 72 years) with moderate dementia were treated orally with the cholinesterase inhibitor tacrine (tetrahydroaminoacridine), 80 mg daily, for several months. The patients were investigated using positron emission tomography (PET) prior to, and after 3 weeks and 3 months of treatment. The PET studies involved a multi-tracer system consisting of [18F]-fluoro-deoxy-glucose (18F-FDG) (tracer for glucose metabolism); 11C-butanol (cerebral blood flow) and (S)(−)- and (R)(+)-[N-11C-methyl]-nicotine (nicotinic receptors; cholinergic neural activity). Tacrine treatment increased the uptake of 11C-nicotine to the brain. Significant reduced difference in uptake between the two enantiomers (S)(−)- and (R)(+)11C-nicotine was observed in the frontal and temporal cortices after tacrine treatment in all three patients. The kinetic analysis indicated increased binding of (S)(−)11C-nicotine in brain compatible with a restoration of nicotinic cholinergic receptors. The most pronounced effect was observed after 3 weeks and 3 months treatment in the patient with mild dementia. An increase in cerebral glucose utilization was found in the 68-year-old patient with mild dementia but also slightly in the 64-year-old man with moderate dementia when treated with tacrine for 3 months. Tacrine administration did not affect cerebral blood flow. The PET data obtained after 3 weeks of tacrine treatment was paralleled by improvement in neuropsychological performance. This study shows in vivo by PET neurochemical effects induced in brain by treatment with tacrine to Alzheimer patients. Intervention with tacrine in the early course of the disease might be necessary for clinical improvement.  相似文献   
20.
INTRODUCTION: During acute inflammation, leukocyte infiltration is mostly neutrophilic, but later monocytes prevail. The majority of inflammatory cells, particularly neutrophilic polymorphonuclear leukocytes (PMNs), become apoptotic at later stages of inflammation and are phagocytosed by neighboring cells, mostly by macrophages. Recently, it has been found that human peripheral blood monocytes also recognize apoptotic cells, which primes them to increased production of interleukin (IL)-10--a cytokine known to reduce phagocytes' ability to engulf and kill pathogens. Based on the above, we studied monocytes' ability to phagocytose and kill Staphylococcus aureus while in contact with apoptotic cells. MATERIALS AND METHODS: Monocytes isolated by elutriation were co-cultured with apoptotic PMNs or Jurkat cells and exposed to viable, human serum-opsonized S. aureus. To induce apoptosis PMNs were cultured overnight while Jurkat cells were UV-treated. Apoptosis, phagocytosis of bacteria and intracellular superoxide production were measured by flow cytometry. Production of reactive oxygen species was also followed by measurement of chemiluminescence. The bactericidal effect was determined by standard colony forming units method. RESULTS: Data presented show that contact of monocytes with apoptotic neutrophils and Jurkat cells had no influence on monocyte phagocytosis of S. aureus, the generation of reactive oxygen species, or the killing of bacteria. CONCLUSION: The data obtained suggest that monocytes attracted to the inflammatory site are not deficient in their ability to cope with pathogens after contact with apoptotic cells despite increased production of IL-10.  相似文献   
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