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671.
Detrimental inflammation of the lungs is a hallmark of severe influenza virus infections. Endothelial cells are the source of cytokine amplification, although mechanisms underlying this process are unknown. Here, using combined pharmacological and gene-deletion approaches, we show that plasminogen controls lung inflammation and pathogenesis of infections with influenza A/PR/8/34, highly pathogenic H5N1 and 2009 pandemic H1N1 viruses. Reduction of virus replication was not responsible for the observed effect. However, pharmacological depletion of fibrinogen, the main target of plasminogen reversed disease resistance of plasminogen-deficient mice or mice treated with an inhibitor of plasminogen-mediated fibrinolysis. Therefore, plasminogen contributes to the deleterious inflammation of the lungs and local fibrin clot formation may be implicated in host defense against influenza virus infections. Our studies suggest that the hemostatic system might be explored for novel treatments against influenza.  相似文献   
672.
A single polypeptide protein (MP 66) of molecular weight 66 kDa purified to homogeneity from melanosomes of normal human skin epidermal melanocytes, was partially characterized. The isoelectric point of MP 66 is in the range of 7.3 to 7.6. This protein, which was shown to inhibit partially purified human skin tyrosinase activity at pH 6.8, also inhibits murine tyrosinase at pH 6.8. However, at pH 5.0, it stimulates murine tyrosinase activity. The physiological implications of these results are discussed.  相似文献   
673.
674.
The hyperlipidemia is a serious health problem that increases the risk of many complications including cardiovascular disease. This study aims to evaluate the possible antihyperlipidemic effects of the feather protein hydrolysate (FPH) in a mice fed with a high‐fat diet (HFD)‐fed mice during 5 weeks. The FPH administration improved dose‐dependent lipid profile, as well as the liver and renal dysfunction indices in hyperlipidemic mice. The FPH also restored the antioxidant status in liver, kidney, and heart by lowering the lipid peroxidation and enhancing the antioxidant enzymes (catalase (CAT), glutathione peroxidase (GPx) and superoxide dismutase [SOD]). Moreover, the histological studies proved that FPH administration prevents hepatic steatosis, glomerular hyperfiltration risk, and cardiac muscle hypertrophy. Accordingly, the FPH is a promising novel medicinal ingredient for possible use in the hyperlipidemic treatment and related complications.  相似文献   
675.
Heme containing proteins are associated with peroxidase activity. The proteins like hemoglobin, myoglobins, cytochrome c and micro-peroxidase other than peroxidases have been shown to exhibit weak peroxidase-like activity. This weak peroxidase–like activity in hemoglobin-like molecules is due to heme moiety. We conducted molecular dynamics (MD) studies to decipher the unfolding path of Ba-Glb (a truncated hemoglobin from Bacillus anthracis) and the role of heme moiety to its unfolding path. The similar unfolding path is also observed in vitro by UV/VIS spectroscopy. The data confirmed that the unfolding of Ba-Glb follows a three state process with a meta-stable (intermediate) state between the native and unfolded conformations. The present study is supported by several unfolding parameters like root-mean-square-deviation (RMSD), dictionary of protein secondary structure (DSSP), and free energy landscape. Understanding the structure of hemoglobin like proteins in unicellular dreaded pathogens like B. anthracis will pave way for newer drug discovery targets and in the disease management of anthrax.  相似文献   
676.
Abstract

Introduction: Deep brain stimulation (DBS) is a standard surgical treatment method which is generally applied to subthalamic nucleus in Parkinson’s patients in cases where medical treatment is insufficient in treating the motor symptoms. It is known that Subthalamic Nucleus Deep Brain Stimulation (STN-DBS) treats many motor symptoms. However, the results of studies on speech and voice vary. The aim of the study is analysing the effect of STN-DBS on the characteristics of voice.

Materials/methods: A total of 12 patients, (8 male–4 female) with an age average of 58.8?±?9.6, who have been applied DBS surgery on STN included in the study. The voice recordings of the patients have been done prior to surgery and 6?months after the surgery. The evaluation of voice has been carried out through the instrumental method. The patients’ voice recordings of the /a,e,i/ vowels have been done. The obtained recordings were evaluated by the Praat programme and the effects on jhitter, shimmer, fundamental frequency (F0) and noise harmonic rate (NHR) were analysed.

Results: Numerical values of F0 of all female participants have been decreased for all of the vowels postoperatively. In the females; jhitter and fraction parameters were found to be significantly different (0.056 and 0.017, perspectively) for the vowel /e/. In addition, p values in the shimmer for vowels /e,i/ were thought to be clinically significant (.087, .079 and .076) respectively. All these changes in second measurements were found to indicate worsening vocal quality after the DBS in females. In males, there is not any significant difference observed between two measures in any of the parameters of any vowels.

Conclusions: Acoustic voice quality deteriorated after STN-DBS predominantly for females however this deterioration was not prominent audio-perceptually. This finding commented as a result of the fact that that voice quality deviance of the participants was not severe.  相似文献   
677.
In the Kingdom of Saudi Arabia (KSA), hospital and population based statistics have shown that breast cancer has the highest crude frequency rate among Saudi women. The scarcity of reports about the disease in the KSA has been the impetus to this analysis about breast cancer in the eastem province of KSA. Data on female patients with invasive breast carcinoma seen at King Fahd Hospital of the University in the eastern province of KSA, were retrospectively reviewed. The analysis intended to examine the pattern of the disease and the outcome for patients. Between 1985 and 1995, 292 patients were identified. Their median age±SD (standard deviation) was 42±10.5 years. Most patients were younger than 50 years (78%) and were predominantly premenopausals (79%). Only 25 (9%) of patients had stage I cancer, whilst 130 (44%), 90 (30%), and 47 (16%) had stage II, III, and IV, respectively. Among patients with known axillary nodal status (242 patients), only 37% were node-negative whilst 32% and 31% had 1–3, and ≥4 positive nodes, respectively. Adjuvant chemotherapy and tamoxifen were commonly offered; nonetheless, other adjuvant modalities were rarely utilised. The median follow-up ±SD of all patients was 62.3±8.9 months: 152 patients (52%) were alive with no evidence of disease, 25 (9%) were alive with evidence of disease, and 115 (39%) were dead from breast cancer or its related complications. The median survival of the entire group was not obtained, but the 10-year projected survival was 55%. For stage I and II patients, 118 (76%) were alive with a projected 10-year actuarial survival of 64%. On the other hand, only 51 (57%) of patients with stage III disease were alive with a median survival of 41.5 months (95% Confidence interval (CI), 18.9 to 51.3). Patients with stage IV disease demonstrated a poor outcome with a median survival of 23.5 (95%, CI 12.2 to 31.4). Multivariate analyses were performed to explore the influence of independent variables on overall survival (OS) for patients with non-metastatic disease. Besides the expected adverse effect of disease progression, the favourable influence of adjuvant chemotherapy and tamoxifen prevailed. The amount of benefit gained from tamoxifen, however, was small. Similar analyses were undertaken to determine the influence of independent variables on progression-free survival (PFS). These analyses ascertained the adverse effects of advanced stage and the favourable impact of adjuvant chemotherapy. Breast cancer in the KSA has features that are distinctive from those of industrialised countries. Survival data, however, were comparable. The favourable influence of adjuvant chemotherapy was evident on both OS and PFS. Adjuvant tamoxifen, however, had little effect. Due to its infrequent use, the role of other adjuvant modalities could not be asserted.  相似文献   
678.
Congenital alacrima is an autosomal dominant disorder showing markedly deficient lacrimation and punctate corneal epithelial erosions. The G (Opitz-Frias) syndrome is also an autosomal dominant disorder characterised by hypertelorism, hypospadias, stridor, and dysphagia. Here we report a 5-year-old boy with the G syndrome presenting congenital alacrima. Received: 23 August 1995 / Revised: 25 September 1995  相似文献   
679.
ObjectiveCardiovascular complications such as cardiomyopathy and endothelial dysfunction, which are frequently seen in patients with acromegaly, are among the most important causes of morbidity and mortality. In this study, we aimed to investigate arterial stiffness, carotid intima-media thickness, endocan level, and A disintegrin and metalloproteinase with thrombospondin type I motif 9 level and their relationship with disease activity in patients with acromegaly with and without cardiovascular risk factors.MethodsA total of 60 patients with acromegaly—25 with active disease, 26 with well-controlled disease, and 9 with newly diagnosed disease—and 60 age-, sex-, and body mass index (BMI)-matched healthy control subjects were enrolled in this study. All the subjects’ height, weight, BMI, systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting plasma glucose (FPG) level, insulin, hemoglobin A1C (HbA1C), C-reactive protein , lipid, endocan, A disintegrin and metalloproteinase with thrombospondin type I motif 9 levels, pulse wave velocity (PWV), and carotid intima-media thickness were measured.ResultsThe SBP, DBP, FPG level, HbA1C level, and PWV of the acromegaly group were higher than those of the control group. In patients with acromegaly with cardiovascular disease (CVD) risk factors, the PWV was higher than that in the control group, and in patients with acromegaly without CVD risk factors, the PWV was similar to that in the control group. In a correlation analysis, a positive correlation was found between PWV and age, BMI, SBP, DBP, FPG level, and HbA1C level in the acromegaly group.ConclusionIn our study, we found that arterial stiffness increased in patients with acromegaly with CVD risk factors and that increased arterial stiffness was associated with hemodynamic (SBP and DBP) and metabolic (BMI, FPG level, and HbA1C level) parameters.  相似文献   
680.
Some heavy metals are known to exert harmful effects by generating an oxidative stress which, in turn, can affect the sexual and reproductive functions of male animals. The addition of antioxidants to the diet could decrease the cytotoxic effect related to oxidative stress (in the presence of heavy metals as food or water contaminants). As a contribution to this problem, the protective effect ofCamellia sinensis green tea, which is know to be rich in antioxidant compounds (polyphenols, etc.), was studied in vanadium-treated adult male rats, with particular attention to growth and genital tract function. White male Wistar rats were given ammonium metavanadate in drinking water (0.46 g/L) for 90 days One group of animals received green tea supplement in drinking water and the control group did not. Chronic vanadium intoxication (without green tea supplement) induced a low growth rate and relative atrophy of the testes, epididymis, prostate and seminal vesicles. Motility and number of spermatozoa were also decreased. Histological examination of the testes revealed atrophy of the seminiferous tubules and defects of spermatogenesis leading to the absence of spermatozoa in 50% of seminiferous tubules. Blood testosterone levels, evaluated by radioimmunoassay, were also decreased from day 2 to day 20. In control animals, these levels were 0.717±0.107 ng/ml; 4.366±0.666 ng/ml and 1.979±0.42 ng/ml on day 2, day 10 and day 20, respectively. After vanadium treatment, they were reduced to 0.043±0.012 ng/ml, 2.494±0.17 ng/ml and 1.086±0.53 ng/ml, respectively, at the same periods. These morphological, histological and functional disorders mostly occured during the first phase of the intoxication period (day 2 to day 10) and were subsequently attenuated, indicating adaptation to the poisoning. In rats receiving green tea, vanadium ingestion did not modify growth rate compared to control animals. Very minor changes were observed in the genital tract. Testicular atrophy and absence of spermatozoa were observed in only some seminiferous tubules. Our results underscore the protective effect of green tea on vanadium poisoning. Polyphenols, which are abundant in green tea, are known to chelate iron. It is proposed that polyphenols may also form insoluble complexes with vanadium, allowing it to be eliminated in the feces. This could explain the decreased effects of vanadium poisoning under our experimental conditions.  相似文献   
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