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121.
Clinical and experimental research findings suggest that a local burn insult produces oxidant-induced organ changes as evidenced by increased lipid peroxidation in lung, liver and gut. Adrenomedullin (AM), a potent vasodilator, was originally isolated from pheochromocytoma cells, and has been identified in other tissues. In this study, we investigated the potential role of AM in burn-induced remote organ damage in rats. Sprague-Dawley rats (250-300 g) were treated with either AM (100 ng/kg, subcutaneously) or saline 10 min before burn insult which covers 30% of total body surface area and were decapitated 24 h after the burn insult. Trunk blood was collected and analyzed for liver and kidney functions and for determination of TNF-alpha levels. The liver, lung and kidney samples were taken for histologic evaluation and for measurement of malondialdehyde (MDA) level, myeloperoxidase (MPO) activity and chemiluminescence levels. The data revealed that AM treatment resulted in a significant protection in tissues tested against burn injury via suppression of lipid peroxidation, tissue neutrophil infiltration, oxidant generation and via decreasing circulating levels of the pro-inflammatory cytokine TNF-alpha. AM treatment was also effective in attenuating hepatic and kidney dysfunction due to burn injury, suggesting that peripherally AM administration may protect the tissues against burn-induced injury.  相似文献   
122.
Inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) may have a direct effect on glucose and lipid metabolism. On the other hand, it is known that IL-6 and TNF-alpha are important pro-inflammatory cytokines in the pathogenesis of atherosclerosis. The goal of present study was to test whether sleep apnea contributes to the previously reported increases of IL-6 and TNF-alpha independent of obesity. Forty-three obese (body mass index, BMI>27 kg/m2) men with newly diagnosed obstructive sleep apnea syndrome (OSAS) (apnea-hypopnea index, AHI> or =5) and age- and BMI-matched 22 obese nonapneic male controls (AHI<5) were enrolled in this study. To confirm the diagnosis, all patients underwent standard polysomnography in the sleep disorders center. Serum samples were taken at 08:00 h in the morning after overnight fasting. Serum IL-6 and TNF-alpha levels were found significantly higher in OSAS patients than in controls (p=0.002, p=0.03). Serum IL-6 and TNF-alpha levels were significantly correlated with AHI in OSAS patients (r=0.03, p=0.046 and r=0.36, p=0.016). There was no significant correlation between serum IL-6, TNF-alpha levels and AHI in controls. Serum IL-6 and TNF-alpha levels were not correlated with BMI both in OSAS patients and controls. In conclusion, circulating IL-6 and TNF-alpha levels in patients with OSAS, as independent of BMI are significantly higher than levels in controls and there is a positive relationship between previously mentioned cytokines' levels and the severity of OSAS. According to these results, the link between cardiovascular morbidity and OSAS may be explained by the coexistence of other cardiovascular risk factors such as circulating IL-6 and TNF-alpha levels.  相似文献   
123.
Hirsutism is a clinical condition commonly encountered in the practice of primary care medicine. The etiology and the age of the patient when it occurs vary widely. Causes range from a basic illness or condition (drug exposure, smoking, idiopathic, and obesity) to complex and serious diseases (Cushing's syndrome, neoplasms, congenital adrenal hyperplasia, insulin-resistance syndromes, hyperprolactinemia, polycystic ovary syndrome, and hyperthecosis). Hirsutism may appear in childhood as well as in older persons. Some drugs (oral contraceptives, L-thyroxine, danazol, and diazoxide), tobacco smoke, some syndromes (polycystic ovary syndrome, obesity, insulin resistance, hyperprolactinemia, hyperthecosis, congenital adrenal hyperplasia, and idiopathic), and some neoplasms (adrenal or ovarian) may lead to hirsutism. The most frequently defined "causes" of hirsutism are polycystic ovary syndrome and idiopathic hirsutism. In hirsutism of gradual onset, hyperprolactinemia, insulin-resistance syndromes, hyperthecosis, polycystic ovary syndrome, and idiopathic hirsutism may be responsible. Cushing's syndrome, neoplasms, and congenital adrenal hyperplasia should be suspected if there has been rapid onset.  相似文献   
124.
An analysis of polymorphism in the fourth component of human complement (C4) was performed on EDTA-plasma from 142 unrelated, randomly selected Turks without collagen-vascular disease or recurrent infections. Plasma samples treated with neuraminidase and carboxypeptidase-B were subjected to high-voltage agarose gel electrophoresis followed by immunofixation. C4B allotypes were further detected in some samples by Western blots with monoclonal antibody 1228 (anti-C4B/Ch1 reactivity). The frequencies of C4A and C4B alleles were determined. Allele C4B*5, which has been found to be relatively common in Asian (Oriental) populations, was not detected in this study. No specific predilection could be noted among the rare variants. C4A*3-C4B*1 was the most common haplotype (n = 40/142, or 28%) but was found less frequently than in Caucasian populations. This finding may be the result of the limited number of samples examined. C4A and/or C4B null allotypes were seen in 49 of 142 (34.6%) subjects. The most frequent C4 null allotype seen was C4B null (37/142, or 26%): 28 subjects had one C4B null allele; 1 had a homozygous deficiency of C4B (C4B*QO, *QO) and 7 had C4A*QO C4B*QO, a double heterozygous haplotype. Frequencies of homozygous haplotype C4A*Q0-C4B*Q0 in the population studied were found to be 0.007. The results of this study demonstrate that the genetic composition of the Turkish population exhibits both similarities and differences with the European population, and ranges between Caucasian and Mongoloid (Asian) populations.  相似文献   
125.
Minor histocompatibility (H) antigens are allogeneic target molecules having significant roles in alloimmune responses after human leukocyte antigen–matched solid organ and stem cell transplantation (SCT). Minor H antigens are instrumental in the processes of transplant rejection, graft-versus-host disease, and in the curative graft-versus-tumor effect of SCT. The latter characteristic enabled the current application of selected minor H antigens in clinical immunotherapeutic SCT protocols. No information exists on the global phenotypic distribution of the currently identified minor H antigens. Therefore, an estimation of their overall impact in human leukocyte antigen–matched solid organ and SCT in the major ethnic populations is still lacking. For the first time, a worldwide phenotype frequency analysis of ten autosomal minor H antigens was executed by 31 laboratories and comprised 2,685 randomly selected individuals from six major ethnic populations. Significant differences in minor H antigen frequencies were observed between the ethnic populations, some of which appeared to be geographically correlated.  相似文献   
126.
Prior reports describing the effects of lanthanum (La(3+)) on red blood cells (RBC) have focused on the effects of this lanthanide on cell fusion or on membrane characteristics (e.g., ion movement across membrane, membrane protein aggregation); the present study explores its rheological and biophysical effects. Normal human RBC were exposed to La(3+) levels up to 200 microM then tested for: (1) cellular deformability using a laser-based ektacytometer and an optical-based rheoscope; (2) membrane viscoelastic behavior via micropipettes; (3) surface charge via micro electrophoresis. La(3+) concentrations of 12.5 to 200 microM caused dose-dependent decreases of deformability that were greatest at low stresses: these rheological changes were completely reversible upon removing La(3+) from the media either by washing with La(3+)-free buffer or by suspending La(3+)-exposed cells in La(3+)-free media (i.e., viscous dextran solution). Both membrane shear elastic modulus and membrane surface viscosity were increased by 25-30% at 100 or 200 microM. As expected, La(3+) decreased RBC electrophoretic mobility (EPM), with EPM inversely but not linearly associated with deformability; changes of EPM were also completely reversible. These results thus indicate novel aspects of RBC cellular and membrane rheological behavior yet raise questions regarding specific mechanisms responsible for La(3+)-induced alterations.  相似文献   
127.
Coeliac disease is a gluten-sensitive enteropathy of varying severity. Osteomalacia and hypocalcaemia can result from malabsorption of vitamin D and calcium, which, in turn, can lead to secondary hyperparathyroidism. If coeliac disease remains untreated for long, tertiary hyperparathyroidism can also develop through autonomy of the parathyroid glands via chronic stimulation. Primary hyperparathyroidism also has been reported in some cases of coeliac disease. We report the case of an adolescent with coeliac disease presenting with severe hypercalcaemia from a parathyroid adenoma. A 14 year-old girl was admitted to our department for delayed puberty and growth retardation. Laboratory examination revealed iron deficiency anaemia, low 25OH vitamin D level (7 ng/ml), high parathyroid hormone level (PTH) (955 pg/ml), and hypercalcaemia (13.4 mg/dl). Endoscopic biopsy was compatible with gluten enteropathy. Endomysium antibody was positive. A gluten-free diet was started. Her calcium returned to normal after excision of the parathyroid adenoma. After four months of the gluten-free diet, she began to mature, and puberty began with development of breasts and axillary-pubic hair growth. It has been suggested that autonomous four-gland hyperplasia or tertiary hyperparathyroidism may progress to adenoma formation, and that this should be termed "quaternary hyperparathyroidism". More studies are required to explain the relationship between coeliac disease and hyperparathyroidism.  相似文献   
128.
Brucella melitensis infection is endemic in the eastern and south-eastern Anatolia regions of Turkey. We report an unusual case of brucella meningitis presenting with bilateral papilla stasis, diplopia and absence of other neurological involvement. Diagnosis was made by positive culture of Brucella spp. with a BACTEC 9120 system with inoculation of the patient's cerebrospinal fluid (CSF). This is the first report of isolation of Brucella spp. from CSF on a BACTEC 9120 system for diagnosis of meningitis. This case demonstrated that brucella meningitis may present with very slight symptoms, and inoculation of CSF into BACTEC bottle besides conventional cultures improves the detection of Brucella in endemic areas such as Turkey.  相似文献   
129.
The N-methyl-d-aspartate receptor (NMDAR), a heteromeric protein, is a glutamate receptor that has three classes of subunits: NR1, NR2, and NR3. It has been reported that these receptors are involved in synaptogenesis, synaptic plasticity, and many other processes in the central nervous system. The aim of this study is to investigate the efficacy of aspirin on hippocampal NMDARs. Sixteen rats were studied in two groups, with eight animals in each group. The first group was the control group, and the second one was the aspirin-given group. Aspirin (acetylsalicylic acid) was administered orally to the rats (200 mg/kg). Tissue samples were obtained after 3 h. The brain was removed, and both hippocampi were dissected out for evaluation. It was found that acute doses of aspirin caused increases on the levels of NMDAR 2A (NR2A) receptors and malondialdehyde (MDA), the end product of lipid peroxidation. Production was significantly increased in the aspirin-given group. We know that MDA is a marker for free radical-mediated tissue damage. In conclusion, lipid peroxidation, caused by acute doses of aspirin may lead to excitotoxicity effects by a hippocampal NR2A-mediated mechanism.  相似文献   
130.
This study investigates genetic structure of loggerhead turtle (Caretta caretta) for conservation purposes using both mitochondrial and nuclear DNA markers. To evaluate overall genetic structure of C. caretta at the Turkish nesting beaches and to compare it with previously published data from other nesting sites of the Mediterranean Sea, we have studied 256 hatchlings from 18 different nesting beaches. Seven distinct haplotypes were detected, of which three have previously been reported from the Mediterranean and one from the Atlantic. The remaining three haplotypes are described for the first time for C. caretta in the present study. Distribution of these haplotypes among the nesting sites showed a significant genetic structuring, indicating that females are philopatric and that gene flow among populations is restricted. Both mtDNA and microsatellite analyses determined genetic structuring (mtDNA: γst = 0.214, p < 0.01; nDNA Fst = 0.0004 p < 0.05) among nesting aggregates of C. caretta throughout the study area and enabled the detection of the different haplotypes to inform conservation strategies.  相似文献   
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