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81.
Activation of the inflammatory response system and varied levels of cytokines in acute schizophrenia have been suggested by recent studies. Psychopharmacologic agents can differentially effect cytokine production, which suggests that therapeutic function of neuroleptics may involve immunomodulation. The present study was carried out to examine: (i) serum concentrations of interleukin (IL)-1beta, soluble interleukin-2 receptor (sIL-2R), IL-6, IL-8 and tumour necrosis factor (TNF)-alpha in schizophrenic patients; (ii) their relation with psychopathological assessment; and (iii) the relation of the initial cytokine levels with responsiveness to risperidone therapy. Thirty-four drug-free schizophrenic patients with acute exacerbation and 23 age- and gender-matched healthy controls were recruited for this study. Psychopathological assessments at admission and throughout risperidone treatment for 60 days were recorded. Serum cytokine concentrations were determined with chemilumunescence assays. According to our results, serum IL-1beta, sIL-2R, IL-6, IL-8 and TNF-alpha concentrations adjusted for age, gender, body mass index and smoking were no different in patients with schizophrenia and controls and among subtypes of schizophrenia. However, the initial TNF-alpha concentrations had a significant effect on Brief Psychiatric Rating Scale and Scale Assessment of Positive Symptoms scores. The initial cytokine concentrations of the patients responsive to risperidone were not significantly different from those of non-responsive patients. The present study demonstrates that plasma levels of IL-1beta, sIL-2R, IL-6, IL-8 and TNF-alpha adjusted for confounding factors are not altered in drug-free schizophrenic patients at acute exacerbation. We suggest that, if cytokine production is altered in schizophrenia, these alterations may not be detectable in systemic circulation. According to our results, the therapeutic effect of risperidone is not related to basal levels of the aforementioned cytokines. However, serum TNF-alpha may contribute to symptomatology in schizophrenia  相似文献   
82.
BACKGROUND: Protein-energy malnutrition (PEM) results from food insufficiency as well as from poor social and economic conditions. Development of PEM is due to insufficient nutrition. Children with PEM lose their resistance to infections because of a disordered immune system. It has been reported that the changes occurring in mediators referred to as cytokines in the immune system may be indicators of the disorders associated with PEM. AIMS: To determine the concentrations of pro-inflammatory cytokines in children with PEM, and to find out whether there was an association with the clinical presentation of PEM. METHODS: The levels of serum total protein, albumin, tumour necrosis factor-alpha, and interleukin-6 were measured in 25 patients with PEM and in 18 healthy children as a control group. PEM was divided into two groups as kwashiorkor and marasmus. The kwashiorkor group consisted of 15 children and the marasmus group consisted of 10 children. RESULTS: Levels of serum total protein and albumin of the kwashiorkor group were significantly lower than both the marasmus group and controls (p < 0.05). In view of tumour necrosis factor-alpha levels, there was no difference between groups (p > 0.05). While levels of interleukin-6 in both the marasmus group and the kwashiorkor group were significantly higher compared with controls (p < 0.05), there was no significant difference between the groups of marasmus and kwashiorkor (p > 0.05). CONCLUSIONS: It was observed that the inflammatory response had increased in children with malnutrition.  相似文献   
83.
The production of cellulases from Stachybotrys microspora strain (A19) has been improved by fed-batch fermentation on Avicel cellulose 10 mg/ml. An endoglucanase EG2 was purified to homogeneity. This cellulase has a molecular mass estimated to 50 kDa when analyzed by a denaturant gel electrophoresis. It exhibited an optimal activity at 50 °C, pH 7.0 and 0.85 M NaCl. Specifically, these results show the thermo-active, alkali-tolerant and halo-tolerant properties of EG2. In addition, this endoglucanase showed its highest activity on barley-β-glucan, compared to the CMC. Moreover, it was less active on Avicel cellulose. Furthermore, the EG2 activity was stimulated in the presence of EDTA, urea and β-mercaptoethanol whereas it was reduced in the presence of SDS. This cellulase was highly stable in the presence of organic solvents such as acetone and n-hexane. TLC showed that the main hydrolysis products from EG2 were cellobiose and glucose. This fungal endoglucanase could be potentially important in the conversion of grass-derived biomass into fermentable sugars.  相似文献   
84.
In crop species, most QTL (quantitative trait loci) mapping strategies use segregating populations derived from an initial cross between two lines. However, schemes including more than two parents could also be used. We propose an approach using a high-density restriction fragment length polymorphism (RFLP) map established on six F 2 populations derived from diallel crosses among four inbred lines and the phenotypic performances of two types of replicated progenies (F 3 and topcross). The QTL is supposed to be on the marker locus considered. Three linear model tests for the detection of QTL effects (T 1, T 2 and T 3) are described and their power studied for the two types of progeny. T 1 tests the global genetic effects of the QTL (additivity and dominance) and T 2 tests only additive effects assuming dominance is absent when it could exist. The models of these two tests assume that the main effects of QTL alleles are constant in different genetic backgrounds. The additive model of test T 3 considers the six F 2 populations independently, and T 3 is the equivalent of the classical mean comparison test if we neglect dominance; it uses only contrasts between the homozygote marker classes. The results show that T 2 is much more powerful than T 3. The power of T 1 and T 2 depends on the relative sizes of the additive and dominance effects, and their comparison is not easy to establish. Nevertheless, T 2 seems to be the more powerful in most situations, indicating that it is often more interesting to ignore dominance when testing for a QTL effect. For a given size of genetic effects, the power is affected by the total number of individuals genotyped in F 2 and the recombination rate between the marker locus and the putative QTL. The approach presented in this paper has some drawbacks but could be easily generalized to other sizes of diallels and different progeny types.  相似文献   
85.
The genome of the sulfate-reducing and anaerobic bacterium Desulfovibrio fructosovorans encodes different hydrogenases. Among them is Hnd, a tetrameric cytoplasmic [FeFe] hydrogenase that has previously been described as an NADP-specific enzyme (Malki et al., 1995). In this study, we purified and characterized a recombinant Strep-tagged form of Hnd and demonstrated that it is an electron-bifurcating enzyme. Flavin-based electron-bifurcation is a mechanism that couples an exergonic redox reaction to an endergonic one allowing energy conservation in anaerobic microorganisms. One of the three ferredoxins of the bacterium, that was named FdxB, was also purified and characterized. It contains a low-potential (Em?=??450?mV) [4Fe4S] cluster. We found that Hnd was not able to reduce NADP+, and that it catalyzes the simultaneous reduction of FdxB and NAD+. Moreover, Hnd is the first electron-bifurcating hydrogenase that retains activity when purified aerobically due to formation of an inactive state of its catalytic site protecting against O2 damage (Hinact). Hnd is highly active with the artificial redox partner (methyl viologen) and can perform the electron-bifurcation reaction to oxidize H2 with a specific activity of 10?μmol of NADH/min/mg of enzyme. Surprisingly, the ratio between NADH and reduced FdxB varies over the reaction with a decreasing amount of FdxB reduced per NADH produced, indicating a more complex mechanism than previously described. We proposed a new mechanistic model in which the ferredoxin is recycled at the hydrogenase catalytic subunit.  相似文献   
86.
The petroleum ether, chloroformic, ethyl acetate, methanolic, Total Oligomers Flavonoids (TOF) enriched extracts, water extract as well as its fractions A1, A2, A3 obtained from aerial parts ofRhamnus alaternus, a Tunisian-Mediterranean medicinal species, were investigated for the contents of phenolic compounds, cytotoxic activity against the K562 human chronic myelogenous leukaemia cell line and L1210 leukaemia murine cells and for antibacterial activity against Gram positive and Gram negative bacterial reference strains. A pronounced cytotoxic effect on both the cell lines was shown in the TOF, ethyl acetate, methanolic, aqueous extracts and A2 fraction, with respectively IC50 values 75, 232, 298, 606 and 571 μg/ml on K562 cells and 198, 176, 767, 560 and 614 μg/ml on L1210 cell line. Significant activity against bacterial reference strains:Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Salmonella enteritidis andSalmonella typhimurium was shown with ethyl acetate, TOF extracts and A2 fraction. The antimicrobial and cytotoxic activities showed byR. alatemus depended on the chemical composition of the tested extracts.  相似文献   
87.
The present study aimed to investigate the diurnal variation of postural stability, attentional capacities, and oral temperature in 5–6-year-old tennis players. A total of 24 young children were divided into two groups: Twelve tennis players with 2 years of training experience and twelve sedentary children without previous experience in any type of sport. They were asked to maintain an upright bipedal stance on a static force platform with eyes open (EO) and eyes closed (EC) at 07:00, 10:00, 14:00, and 18:00 h. Postural stability was evaluated by the center of pressure (CoP), surface area (CoPArea), CoP mean velocity (CoPVm), and Romberg’s index (RI). Oral temperature and simple reaction time (SRT) were also recorded at the beginning of each test session. Postural stability in 5–6-year-old tennis players was low at 07:00 h and improved at 10:00 h (p < 0.001); then, it worsened at 14:00 h (p < 0.001) and improved again at 18:00 h (p < 0.001) as found in sedentary children. This rhythm was also close to that of SRT in both groups. Body temperature increased significantly (p < 0.001) from the morning to the afternoon in both groups. However, the peak of postural performance, the peak of attentional capacities, and the greatest vision contribution to maintain balance observed at 18:00 h were only found in the trained group. Moreover, young tennis players were more stable (p < 0.001) and more attentive (p < 0.01) than sedentary ones at 18:00 h. The amplitude of the diurnal rhythm of CoP parameters was significantly larger (p < 0.01) in trained children compared to sedentary ones (43.1 ± 8.5 vs 31.7 ± 8.3 for the CoPArea; 27.5 ± 7.4 vs 17.7 ± 8.2 for the CoPVm). Therefore, time-of-day has a significant effect on static postural stability and attentional capacities in young tennis players with better performances in the late afternoon (habitual hour of training). Thus, we recommend planning some training sessions at 07:00 and/or 14:00 h to optimize postural stability at the time of its batyphase and to reduce the incidence of fall-related injury risks during this critical age in athletic environments.  相似文献   
88.
89.

Introduction

Undescended testis is a frequent congenital disease, more often diagnosed and treated during childhood. However, due to ignorance or negligence, this disease can be seen even after puberty, when it raises a therapeutic problem: is orchidopexy still useful? This study was designed to evaluate the outcome of orchidopexy at adulthood in terms of improvement of fertility and prevention of malignant degeneration.

Material and methods

Retrospective study performed over a 23-year period (1983–2005). We have found 259 patients with undescended testis diagnosed and treated after the age of 18 years.

Results

The mean age of patients was 24 years (range: 18–63). In the majority of cases, undescended testis was diagnosed at a systemic medical examination in 199 patients (77% of cases), and in a context of infertility in 33 patients, testicular malignancy in 8 patients, testicular torsion in 2 patients and, in 17 cases, undescended testis had been known since birth but was neglected by the parents. Undescended testis was unilateral in 209 cases and bilateral in 50 cases. Out of 37 couples, only 4 gave birth to children (10.8% paternity rate). Sperm analysis was abnormal in all infertile patients. All patients were treated by orchidopexy, except for 36 patients in whom orchidectomy was performed due to testicular atrophy (27 cases), malignancy (8 cases) or necrosis (1 case). Biopsy of the intrascrotal testis was performed in 3 patients with unilateral cryptorchidism. Histological examination was normal in two cases and abnormal in one case. The long-term outcome was characterized by:
  1. Testicular atrophy in 6 patients (2.7% of cases).
  2. Progression to malignancy in 3 patients (1.3% of cases).
  3. Improvement of sperm parameters in 16 of 33 infertile patients (48.5%); 4 patients fathered children after treatment.

Conclusion

Orchidopexy at adulthood can lead to improvement of infertility. It can also decrease the incidence of malignancy and facilitate clinical examination looking for possible malignancy. However, the best treatment remains preventive, based on early diagnosis and orchidopexy.  相似文献   
90.
Irisin was first identified in skeletal muscle cells. It is an exercise protein that is secreted into the circulation; it causes conversion of white adipose tissue to brown adipose tissue. We investigated irisin immunoreactivity in mole rat (Spalax leucodon) tissues. We examined cerebellum, pituitary, heart, liver, pancreas, spleen, uterus, kidney and striated muscle in female adult mole rats. Tissues were processed, embedded in paraffin, sectioned at 5 μm and stained immunohistochemically for irisin. Irisin immunostaining was detected in the cytoplasm of stained cells; the cytoplasm of Purkinje cells was unstained. We found that irisin may be synthesized in many tissues. The function of locally synthesized irisin currently is unknown.  相似文献   
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