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21.
Serum zinc and magnesium levels in patients with blastocystosis   总被引:2,自引:0,他引:2  
The aim of the study was to investigate the total content of the essential elements of zinc and magnesium levels in patients infected with Blastocystis hominis. Zinc and magnesium concentrations were measured in 52 patients who were positive for the intestinal parasite Blastocystis hominis. Scores were obtained for the positives and their age- and sex-matched 60 Blastocystis hominis-negative healthy controls. For comparison of two groups of continuous variables, the independent samples t-test was used. The mean concentration of magnesium in blood was significantly lower in Blastocystis hominis-positive patients than in their controls both in females (p<0.05) and males (p<0.05). The average zinc concentration in Blastocystis hominis-positive female patients was 0.61±0.2 mg/L and 0.60±0.2 mg/L in controls (p>0.05). The mean values of the zinc in blood were 0.62±0.2 mg/L in Blastocystis hominis-positive male patients and 0.82±0.1 in controls (p>0.05). No correlation could be demonstrated between age and mean values of zinc and magnesium in Blastocystis-positive females/males and controls (p>0.05). No significant correlation could be found between blood zinc and magnesium levels in Blastocystis-positive female/male patients and controls (p>0.05). Magnesium levels were found to be clearly decreased, whereas no change was observed in zinc levels in the patients with Blastocystis compared to controls.  相似文献   
22.
Ca(2+) influx triggered by depletion of sarcoplasmic reticulum (SR) Ca(2+) stores [mediated via store-operated Ca(2+) channels (SOCC)] was characterized in enzymatically dissociated porcine airway smooth muscle (ASM) cells. When SR Ca(2+) was depleted by either 5 microM cyclopiazonic acid or 5 mM caffeine in the absence of extracellular Ca(2+), subsequent introduction of extracellular Ca(2+) further elevated [Ca(2+)](i). SOCC was insensitive to 1 microM nifedipine- or KCl-induced changes in membrane potential. However, preexposure of cells to 100 nM-1 mM La(3+) or Ni(2+) inhibited SOCC. Exposure to ACh increased Ca(2+) influx both in the presence and absence of a depleted SR. Inhibition of inositol 1,4,5-trisphosphate (IP)-induced SR Ca(2+) release by 20 microM xestospongin D inhibited SOCC, whereas ACh-induced IP(3) production by 5 microM U-73122 had no effect. Inhibition of Ca(2+) release through ryanodine receptors (RyR) by 100 microM ryanodine also prevented Ca(2+) influx via SOCC. Qualitatively similar characteristics of SOCC-mediated Ca(2+) influx were observed with cyclopiazonic acid- vs. caffeine-induced SR Ca(2+) depletion. These data demonstrate that a Ni(2+)/La(3+)-sensitive Ca(2+) influx via SOCC in porcine ASM cells involves SR Ca(2+) release through both IP(3) and RyR channels. Additional regulation of Ca(2+) influx by agonist may be related to a receptor-operated, noncapacitative mechanism.  相似文献   
23.
Chronic inflammation is a common feature of end-stage renal disease, which carries a heightened risk of atherosclerosis and other co-morbid conditions. Dialysis treatment per se can bring additional risk factors for inflammation, such as increased risk of local graft and fistula infections, impure dialysate or bio-incompatible membranes. Our study was designed to determine whether a hemodialysis session leads to an acute substantial alteration in the plasma levels of the proinflammatory cytokines interleukin (IL)-6, IL-1beta and tumor necrosis factor (TNF)-alpha, the T-lymphocyte activation factor soluble IL-2 receptor (sIL-2R), and an inflammation mediator and chemotactic granulocyte factor, IL-8, in end-stage renal disease patients receiving chronic intermittent HD. In this study, 21 (12 male/nine female) patients undergoing chronic hemodialysis were enrolled. The acute effect of a hemodialysis session on serum cytokine concentrations was assessed by comparison of pre-hemodialysis and post-hemodialysis determinations. Serum IL-1beta, sIL-2R, IL-6, IL-8 and TNF-alpha levels were determined with chemiluminescence enzyme immunometric assays. A significant difference was not observed for IL-1beta, IL-6, TNF-alpha, and sIL-2R concentrations in pre-hemodialysis and post-hemodialysis specimens (p>0.05). Serum median (25th-75th percentiles) IL-8 concentration was 69.4 (34.9-110.3) pg/ml before hemodialysis, and decreased to 31.5 (18.0-78.8) pg/ml following hemodialysis (p: 0.006). Clearance of IL-8 increased by 0.47+/-0.08 pg/ml for each unit increase in pre-dialysis IL-8 (p<0.001) and decreased by 5.63+/-2.59 pg/ml for each unit increase in pre-dialysis urea mmol/l (p<0.05). In conclusion, the results of our study demonstrate that a hemodialysis session markedly decreases IL-8 concentration, which is significantly affected by pre-dialysis concentrations, indicating that removal of IL-8 is a concentration gradient-dependent action, but does not change the serum levels of IL-1beta, sIL-2R, IL-6, and TNF-alpha, underlining importance of the structural characteristics of the molecules.  相似文献   
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25.
OBJECTIVE: To study natural killer cells' spontaneous cytotoxic capacity against tumor cells and their prognostic significance in classical Hodgkin's disease. STUDY DESIGN: Thirty-eight pediatric mixed cellularity and nodular sclerosing Hodgkin's disease patients were included in the study. Immunohistochemical staining was performed for natural killer cells in the background using the monoclonal antibody CD57 in serial sections of B5-formalin-fixed, paraffin-embedded tissue blocks. CD57-positive cells were counted with an immersion objective among 5,000 cells on representative areas of the tumors. The degree of natural killer cells was classified as low (<150 cells) or high (> or = 150 cells). Multivariate regression analysis was performed to determine the differences between patients with and without relapse. RESULT: The mean of CD57-positive cell numberfor all the cases was 173.42 +/- 117.34 (range, 20-500). CD57-positive cells were high in 21 cases and low in 17. The mean of CD57-positive cell numbers was 191.85 +/- 115.33 in the disease-free group and 84.44 +/- 57.90 in the relapsing group. Log rank analysis showed statistical significance between event-free survival and number of CD57-positive cells (P = .0207). CONCLUSION: In multivariate analysis, CD57 expression proved to be a prognostic factor independent from otherfactors. As a result, CD57 expression by background natural killer cells may be used as a prognostic parameter in mixed cellularity and nodular sclerosing Hodgkin's disease.  相似文献   
26.
The aim of the study was to investigate the changes of total content of the essential elements of zinc and magnesium levels in patients infected with Giardia intestinalis. Zinc and magnesium concentrations were measured in 64 patients who were positive for the intestinal parasite G. intestinalis. Scores were obtained for the positives and their 60 age- and sex-matched G. intestinalis-negative healthy controls. The mean concentration of magnesium in blood was significantly lower in G. intestinalis-positive patients than in their controls both in females (p<0.05) and males (p<0.05). The average zinc concentration in G. intestinalis-positive female patients was 0.76±0.3 mg/L and it was 0.60±0.2 mg/L in controls (p>0.05). The mean values of the zinc in blood were 0.73±0.2 mg/L in G. intestinalis-positive male patients and 0.82±0.1 mg/L in controls (p>0.05). No correlation could be demonstrated between age and mean values of zinc and magnesium in both G. intestinalis-positive females/males and controls (p>0.05). No significant correlation could be found between blood zinc and magnesium levels in G. intestinalis-positive female/male patients and controls (p>0.05). Magnesium levels were found to be clearly decreased, whereas no change was observed in zinc level in the patients infected with G. intestinalis compared to controls.  相似文献   
27.
Polyacylonitrile fibers (PAN) surfaces were modified with chemical polymerization of conductive polyaniline (PANI) in the presence of potassium dichromate as an oxidizing agent. The effect of aniline concentration on the grafting efficiency and on the electrical surface resistance of PAN/PANI composite fibers was investigated. The surface resistance of the conductive composite fibers in this work was found to be between 8.0 and 0.5 kΩ/cm. As the amount of grafted PANI increased on the PAN fibers the electrical resistance of composite fibers decreased. The PAN/PANI composite fibers were characterized by SEM and FTIR studies. Composite PAN/PANI fibers were used for reversible immobilization of invertase. The immobilization efficiency and the activity of the immobilized invertase (from 1.0 mg/mL invertase solution at pH 5.5) were increased with increasing PANI contents of the composite fibers. The maximum amount of immobilized enzyme onto composite fibers containing 2.0% PANI was about 76.6 mg/g. The optimum pH for the free enzyme was observed at 5.0. On the other hand, immobilized invertase yielded a broad optimum pH profile between pH 5.0 and 7.0. Immobilized invertase exhibited 83% of its original activity even after two months storage at 4 °C while the free enzyme showed only 7% of its initial activity.  相似文献   
28.
29.

Background

Chronic schistosomiasis is associated with T cell hypo-responsiveness and immunoregulatory mechanisms, including induction of regulatory T cells (Tregs). However, little is known about Treg functional capacity during human Schistosoma haematobium infection.

Methodology

CD4+CD25hiFOXP3+ cells were characterized by flow cytometry and their function assessed by analysing total and Treg-depleted PBMC responses to schistosomal adult worm antigen (AWA), soluable egg antigen (SEA) and Bacillus Calmette-Guérin (BCG) in S. haematobium-infected Gabonese children before and 6 weeks after anthelmintic treatment. Cytokines responses (IFN-γ, IL-5, IL-10, IL-13, IL-17 and TNF) were integrated using Principal Component Analysis (PCA). Proliferation was measured by CFSE.

Principal Findings

S. haematobium infection was associated with increased Treg frequencies, which decreased post-treatment. Cytokine responses clustered into two principal components reflecting regulatory and Th2-polarized (PC1) and pro-inflammatory and Th1-polarized (PC2) cytokine responses; both components increased post-treatment. Treg depletion resulted in increased PC1 and PC2 at both time-points. Proliferation on the other hand, showed no significant difference from pre- to post-treatment. Treg depletion resulted mostly in increased proliferative responses at the pre-treatment time-point only.

Conclusions

Schistosoma-associated CD4+CD25hiFOXP3+Tregs exert a suppressive effect on both proliferation and cytokine production. Although Treg frequency decreases after praziquantel treatment, their suppressive capacity remains unaltered when considering cytokine production whereas their influence on proliferation weakens with treatment.  相似文献   
30.
Fatimah SS  Ng SL  Chua KH  Hayati AR  Tan AE  Tan GC 《Human cell》2010,23(4):141-151
Human amniotic epithelial cells (hAECs) are potentially one of the key players in tissue engineering due to their easy availability. The aim of the present study was to develop an optimal isolation and transportation technique, as well as to determine the immunophenotype and epithelial gene expression of hAECs. Amnion was mechanically peeled off from the chorion and digested with trypsin-ethylenediaminetetraacetic acid. The isolated hAECs were cultured in medium containing 10 ng/mL epidermal growth factor until P4. The epithelial gene expression, cell surface antigen and protein expression of hAECs were analyzed by quantitative polymerase chain reaction, flow cytometry and immunocytochemistry. hAECs were also cultured in adipogenic, osteogenic and neurogenic induction media. The best cell yield of hAECs was seen in the digestion of 15 pieces of amnion (2 × 2 cm) and isolated 30 min after digestion with trypsin. F12:Dulbecco's modified eagle medium was the best medium for short term storage at 4 °C. hAECs expressed CD9, CD44, CD73 and CD90, and negligibly expressed CD31, CD34, CD45 and CD117. After serial passage, CK3, CK19 and involucrin gene expressions were upregulated, while p63, CK1 and CK14 gene expressions were downregulated. Sustained gene expressions of integrin β1 and CK18 were observed. At initial culture, these cells might have stem-like properties. However, they differentiated after serial passage. Nonetheless, hAECs have epithelial stem cell characteristics and have the potential to differentiate into corneal epithelial cells. Further investigations are still needed to elucidate the mechanism of differentiation involved and to optimize the culture condition for long term in vitro culture.  相似文献   
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