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51.
Lactulose and lactitol, non-absorbable disaccharides, prevent bacterial translocation (BT) arising from the gut. In contrast, lack of food into the gut leads to coliform bacterial overgrowth and even if it does not cause BT, can induce the risk from other stimuli for BT. In this study, we tested whether lactulose and lactitol affected populations of coliform bacteria in the caecum during starvation in Sprague-Dawley rats. Three groups of rats were starved for 72 h and given oral 2 ml undiluted lactulose (670 mg/ml), 2 ml undiluted lactitol (666 mg/ml) or 2 ml physiological saline, respectively, once a day. The caecum and mesenteric lymph nodes (MLNs) were removed for microbiological and histopathological analyses. The highest degree of coliform bacterial overgrowth, BT to MLNs and histopathological damage were observed in lactulose-treated rats, followed by the group treated with lactitol. As a result of this study, both drugs, especially lactulose augmented the proliferation and translocation tendency of coliform bacteria in the caecum during 72-h starvation in rats.  相似文献   
52.
A thiol compound, glutathione, is essential for healthy cell defence against xenobiotics and oxidative stress. Glutathione reductase (GR) and glutathione S-transferase (GST) are two glutathione-related enzymes that function in the antioxidant and the detoxification systems. In this study, potential inhibitory effects of methyl 4-aminobenzoate derivatives on GR and GST were examined in vitro. GR and GST were isolated from human erythrocytes with 7.63 EU/mg protein and 5.66 EU/mg protein specific activity, respectively. It was found that compound 1 (methyl 4-amino-3-bromo-5-fluorobenzoate with Ki value of 0.325±0.012 μM) and compound 5 (methyl 4-amino-2-nitrobenzoate with Ki value of 92.41±22.26 μM) inhibited GR and GST stronger than other derivatives. Furthermore, a computer-aided method was used to predict the binding affinities of derivatives, ADME characteristics, and toxicities. Derivatives 4 (methyl 4-amino-2-bromobenzoate) and 6 (methyl 4-amino-2-chlorobenzoate) were estimated to have the lowest binding energies into GR and GST receptors, respectively according to results of in silico studies.  相似文献   
53.
By adding a biomass carrier to an activated sludge system, the biomass concentration will increase, and subsequently the organic removal efficiency will be enhanced. In this study, the possibility of using excess sludge from ceramic and tile manufacturing plants as a biomass carrier was investigated. The aim of this study was to determine the effect of using fireclay as a biomass carrier on biomass concentration, organic removal and nitrification efficiency in an activated sludge system. Experiments were conducted by using a bench scale activated sludge system operating in batch and continuous modes. Artificial simulated wastewater was made by using recirculated water in a ceramic manufactutring plant. In the continuous mode, hydraulic detention time in the aeration reactor was 8 and 22 h. In the batch mode, aeration time was 8 and 16 h. Fireclay doses were 500, 1,400 and 2,250 mg l−1, and were added to the reactors in each experiment separately. The reactor with added fireclay was called a Hybrid Biological Reactor (HBR). A reactor without added fireclay was used as a control. Efficiency parameters such as COD, MLVSS and nitrate were measured in the control and HBR reactors according to standard methods. The average concentration of biomass in the HBR reactor was greater than in the control reactor. The total biomass concentration in the HBR reactor (2.25 g l−1 fireclay) in the continuous mode was 3,000 mg l−1 and in the batch mode was 2,400 mg l−1. The attached biomass concentration in the HBR reactor (2.25 g l−1 fireclay) in the continuous mode was 1,500 mg l−1 and in the batch mode was 980 mg l−1. Efficiency for COD removal in the HBR and control reactor was 95 and 55%, respectively. In the HBR reactor, nitrification was enhanced, and the concentration of nitrate was increased by 80%. By increasing the fireclay dose, total and attached biomass was increased. By adding fireclay as a biomass carrier, the efficiency of an activated sludge system to treat wastewater from ceramic manufacturing plants was increased.  相似文献   
54.
Turkey remains an intermediate area for prevalence of hepatitis B virus (HBV) surface antigenemia. The sheep-raising areas of Turkey also pose a high risk for cystic hydatid disease (CHD). Both HBV infection and CHD are major public health issues particularly in eastern parts of Turkey; however, there is no data regarding HBV infection in patients who have had CHD. The aims of this study were to evaluate the association between HBV infection and CHD and suggest ways to reduce HBV infection which is still widespread in Turkey. A retrospective study was conducted with 94 adult patients with active CHD referred to the hepatology department, Yuzuncuyil University School of Medicine from December 2010 to December 2012. All subjects came from rural areas of the region and underwent ultrasonography of abdomen which detected CHD of the liver. All the patients were serologically positive for Echinococcus granulosus. The control group consisted of 500 patients (300 men and 200 women) referred to the internal medicine clinics for other reasons. The patients with CHD and in the control group were tested for the existence of HBs antigen according to the standard procedures. The seroprevalence of HBs antigen was significantly higher in patients with active CHD than those in the control group (12.7% vs 5.2%; P=0.0017). Our data indicate that there is significant association between HBV infection and CHD. All patients with CHD should be screened for HBV infection.  相似文献   
55.
Measurement of the real dielectric constant of bulk buffer solutions containing short sequences of DNA as a function of temperature through the DNA melting or denaturiztion transition can be used to determine melting temperatures, T(m), and to estimate the binding energy of the complimentary strands. We describe a preliminary dielectric measurement and analysis protocol to determine these parameters and its application to two known short sequences. The relative real dielectric constant for the bulk solutions was determined over the frequency range of 50 Hz-20 kHz and temperature range of <40-65 degrees C. The measurements were performed on dilute solutions and utilized low electric field strengths. Based on fits to the data by modified sigmoid functions, the melting temperatures, width of transition, and binding energy for the two sequences in solution were estimated. It was observed that the order of the transition appeared to be second order. The results were then compared against predictions of a number of models from the literature that provide theoretical estimates for the melting temperatures of known short sequences of DNA.  相似文献   
56.

The arthroconidial yeasts Magnusiomyces capitatus and M. clavatus are emerging opportunistic pulmonary pathogens. They are closely related and difficult to distinguish based on morphological and physiological traits. We applied an SYBR® green-based quantitative PCR (qPCR) assay to identify the species. We analyzed 30 reference strains originating from clinical and environmental sources by targeting the Rpb2 gene encoding the second largest subunit of RNA polymerase II. The qPCR assays were tested by direct identification of M. capitatus and M. clavatus in spiked sputum and household dishwasher swabs, respectively, as models for clinical and environmental samples. The assays were proved to be reliable for species-level identification of both species, with 100% sensitivity and 100% specificity, lowest inter-assay deviations (RSDr?≤?1.65%, R2 values >0.99), detection limit of 10 theoretical copy number of target DNA, and detection cell limit of ≥5000 yeast cells from spiked sputum samples. The developed qPCR assay is a practical molecular approach for the detection of M. capitatus and M. clavatus that can be used as a stand-alone assay or in conjunction with culture-dependent approaches.

  相似文献   
57.
AIM: Weill-Marchesani syndrome (WMS) is a rare systemic disorder with both autosomal recessive and dominant inheritances. Accumulation of reactive oxygen species such as O2*-, H2O2 and OH* causes lipid peroxidation (LPO), whereas antioxidant enzymes (superoxide dismutase (SOD), glutathione peroxidase (GSHPx)) mediate defence against oxidative stress. Excess tumour necrosis factor (TNF)-alpha and NO* react with O2*- and cause further antioxidant depletion with an increase in mutation frequency by H2O2. This study investigated the levels of SOD, GSHPx, catalase (CAT), TNF-alpha, NO and LPO in patients with WMS. METHODS: A group of 10 WMS patients (four males, six females; age, 26.5+/-19.0 years) and 10 age-matched and sex-matched controls (five males, five females; age, 27.3+/-18.2 years) were included. Serum TNF-alpha levels were determined by a spectrophotometer technique using immulite chemiluminescent immunometric assay. Malondialdehyde (MDA) was determined in plasma; CAT in red blood cells (RBCs), and SOD and GSHPx in both plasma and RBCs. Total serum NO* levels were evaluated by Griess reaction. RESULTS: Mean levels of TNF-alpha (8.3+/-0.6 pg/ml) in WMS patients were significantly (p<0.001) higher than controls (4.3+/-0.2 pg/ml). Plasma MDA levels in patients and controls were 5.4+/-0.8 and 1.8+/-0.6 micromol/l, respectively, and the difference was significant (p=0.0002). SOD and GSHPx activities were significantly lower in both RBCs and plasma of WMS than in controls (RBC-SOD, 3981.9+/-626.6 versus 5261.6+/-523.0 U/g haemoglobin (Hb), p=0.0005; plasma-SOD, 529.4+/-49.3 versus 713.4+/-55.7 U/g protein, p=0.0002; RBC-GSHPx, 682.7+/-42.0 versus 756.5+/-47.6 U/g Hb, p=0.0011; plasma-GSHPx, 107.3+/-15.0 versus 131.4+/-19.7 U/g protein, p=0.0113). In addition, serum NO (NO*-2 + NO*-3) levels were also significantly (p = 0.0002) increased in WMS patients (54.4+/-5.7 versus 26.9+/-6.7 micromol/l). RBC-CAT levels were similar between groups (125.6+/-21.3 versus 131.0+/-21.5 k/g Hb, p = 0.8798). CONCLUSIONS: The elevated LPO, TNF-alpha and NO* with decreased antioxidant enzyme activities indicated impaired antioxidative defence mechanisms with an oxidative injury and cell toxicity in WMS patients. The use of multiple antioxidants and free radical scavengers might be helpful in this genetic disorder.  相似文献   
58.
Ethanol at 50% (v/v) and sodium bicarbonate at 1% (wt/v), either alone or in combination, were applied to organically grown strawberries 1 h before harvest to control the natural incidence of postharvest diseases. Botrytis cinerea was the major cause of decay in all of the experiments. In three experiments, ethanol significantly reduced the decay incidence after storage for 3 days at 1°C followed by 2 days at 24°C, while the efficacy of sodium bicarbonate was inconsistent. The combination of ethanol and sodium bicarbonate did not increase their efficacy. Postharvest hot water dips at 55 and 60°C for 30 s significantly reduced the decay incidence to 3.4 and 2.7%, respectively, while decay incidence in the control was 28.5% (the first experiment). The efficacy of the hot water treatments at 55 and 60°C for 30 s was consistent in three experiments. In the third experiment, the efficacy of hot water treatment at 60°C was significantly higher than that of hot water treatment at 55°C. All pre‐ and postharvest treatments significantly reduced natural fungal populations on the surfaces of fruits. None of the pre‐ and postharvest treatments caused surface injuries to the fruit or adversely affected weight loss and taste parameters.  相似文献   
59.
It is accepted that angiogenesis plays an important role in the development of the corpus luteum (CL) and is probably necessary for normal lutein cell function. A number of drugs currently being tested in clinical trials as possible angiogenesis inhibitors were not originally developed with the intention of suppressing tumor angiogenesis. Interferon alpha (IFN-alpha) is one of the notable examples of such 'accidental angiogenesis inhibitors' and daily administration of IFN-alpha is known to suppress tumor growth, tumor vascularization, and down-regulation of various growth factors. We investigated the effects of IFN-alpha treatment on the expression of vascular endothelial growth factor (VEGF), and its receptors KDR and Flt-1, and CD34 in CL during the first week of pseudopregnancy and pregnancy in hormonally induced rat ovaries by immunohistochemistry and Western blot techniques. Basal body temperatures of the drug-treated rats, as an indicator of treatment effect, were determined daily and were increased significantly when compared to controls (38.03 +/- 0.18 vs. 36.6 +/- 0.1 degrees C), respectively. The effect of IFN-alpha treatment was minimal when the entire week was evaluated, however, the expression of VEGF decreased at 3rd, 5th, and 7th days of both pregnancy and pseudopregnancy, when compared to the 1st day, whereas there was not a such alteration in the untreated rats regarding these days. The daily subcutaneous administrations of 672.500 U IFN-alpha2b had minimal effects on the expressions of VEGF, and its two receptors KDR and Flt-1 in either pregnant or pseudopregnant corpora lutea utilizing HSCORE.  相似文献   
60.
The nanoparticle (NP)-induced conformational changes of protein and NP agglomeration have gained a remarkable interest in medical and biotechnological fields. Herein, the effect of human hemoglobin (Hb) on the colloidal stability of cerium oxide NP (CNP) was investigated by dynamic light scattering (DLS), zeta potential, and TEM analysis. In addition, the effect of CNP on the heme degradation and structural changes of Hb was studied using fluorescence, circular dichroism (CD), and UV–visible (UV–vis) spectroscopic methods. DLS and TEM analysis showed that the presence of Hb can increase the mean diameter of CNP. Zeta potential measurements revealed that CNP demonstrated a higher charge distribution relative to CNP/Hb complex. Besides, fluorescence studies indicated that two fluorescent heme degradation products are revealed during the interaction of CNP with Hb. Near UV-CD spectroscopy also showed that the microenvironmental changes of heme groups occur after interaction of Hb with CNP. The result of thermal behavior of Hb confirmed the structural changes of protein, which referred to decrease in the Hb stability in the presence of CNP. Indeed, the finding related to structural and functional changes of Hb induced by CNP may be crucial to obtain information regarding the side effects of NPs. Finally, this data reveal much insight into the effects of the interaction on protein structural changes and NP agglomeration, and can correlate the zeta potential of NP-protein complexes with the nature of the principle NP-protein interaction.  相似文献   
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