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171.
Hamann  KJ; Neeley  SP; Dowling  TL; Grant  JA; Leff  AR 《Blood》1996,88(9):3575-3582
We examined the selective effects of interleukin (IL-5) in regulating the maturational expression of surface adhesion molecules on human eosinophils and adhesion to endothelial cells during eosinophiiopolesis in vitro. Expression of the beta 2 integrins (CD11/CD18) and the beta 1 integrin, VLA-4 (CD49d/ CD29), was assessed during development in culture with IL-3, IL-5, and granulocyte-macrophage colony stimulating factor in cultures of human umbilical cord blood-derived eosinophil (CDE) precursor cells. Expression of both CD11b and CD18 subunits of Mac-1 was lower on CDE which were continuously (= chronically) exposed to IL-5 than on CDE which were cultured without IL-5 for the final week of culture. CD11b expression on cells grown without IL-5 was 71.3 +/- 5.92 (mean specific fluorescence value [MSF] as measured by flow cytometry) versus 52.5 +/- 4.48 MSF for Mac-1 alpha (CD11b) on CDE grown in the continued presence of 2 x 10 - 11 mol/L IL-5 (P < .01). Although expression of VLA-4 decreased as CDE matured, expression of CD29 and CD49d were similar regardless of cytokine exposure for the final week of culture. For eosinophils cultured without IL-5, acute stimulation with 10 - 8 mol/L IL-5 increased CD11b surface expression and increased the number of cells adhering to unstimulated human umbilical vein endothelial cells (HUVEC) from 4,570 +/- 780 cells (9.14 +/- 1.56% adhesion) to 8,385 +/- 515 cells (16.8 +/- 1.03% adhesion) (P < .01). Basal adhesion to unstimulated HUVEC of CDE cultured continuously with IL-5 was comparable (8.62 +/- 1.12% adhesion; P = NS), but neither CD11b expression (50.3 +/- 11.8 MSF; P = NS v control) nor adhesion to HUVEC (6.77 +/- 1.35%; P = NS) was enhanced in these eosinophils after acute stimulation with IL-5. Blockade of adhesion to IL-1-stimulated HUVEC caused by the anti-CD49d monoclonal antibody (MoAb), HP2/1, was comparable for cells cultured with IL-5 and without IL-5. However, the anti-CD18 MoAb, R15.7, caused 47.6 +/- 5.08% inhibition of adhesion of eosinophils cultured without IL-5 and only 25.8 +/- 5.20% for cells cultured continuously with IL-5 (P < .01), and failed to block significantly the adhesion of only the latter cells to IL-4-stimulated HUVEC. Our data show that continuous, chronic exposure to low concentrations of IL-5 causes decreased expression of Mac-1 and refractoriness to acute stimulation with IL-5 of adhesion to HUVEC. These data further demonstrate that CDE maturing in the continued presence of IL-5 adhere to HUVEC predominantly through VLA-4 ligation.  相似文献   
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Introduction

Epidural anaesthesia (EA) has been the accepted standard for postoperative analgesia in open abdominal surgery. However, it is not without significant risk. This study aimed to audit the effect of EA and ultrasonography placed rectus sheath catheters (RSCs) on analgesia as well as the incidence of postoperative complications following open colorectal cancer surgery.

Methods

A three-year retrospective case note review was undertaken of all patients undergoing open colorectal cancer surgery at the Royal Devon and Exeter Hospital NHS Foundation Trust who received either EA or RSC for postoperative analgesia under the care of the senior authors. A single surgeon and single anaesthetist were practitioners.

Results

The case notes of 120 patients were reviewed retrospectively: 85 patients had EA and 24 RSC while 11 patients were excluded from the study. The EA group experienced a significantly higher incidence of hypotension (systolic blood pressure <130mmHg) than the RSC group on the first postoperative day (p=0.0001). There was no significant difference in pain score or opiate sparing properties between the groups (p=0.92). There was no significant difference in postoperative respiratory tract infection, anastomotic leak or wound complications between the groups (p=0.2, p=1.0 and p=0.5 respectively). The RSC group had a higher incidence of ileus than the EA group (4/24 vs 2/85, p=0.026). However, the numbers were too small to draw a reliable conclusion.

Conclusions

The use of ultrasonography guided RSCs has demonstrated effective postoperative analgesia equivalent to EA with the potential benefits of a reduced incidence of hypotension. A prospective randomised trial is now underway to compare RSC and EA in open abdominal and pelvic surgery.  相似文献   
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Background

The purpose of this study was to evaluate antileishmanial effects of ASA via NO pathway in Leishmania major infected Balb/c mice. Moreover, toxicity and pathological consequences of ASA administration were investigated.

Methods

Balb/c mice were infected with L. major and ASA was inoculated orally after lesion appearance for its ability to modulate NO and to modify Leishmania infection in host, in order to evaluate the effects of NO production on size and lesion macroscopy, delay of lesion formation and proliferation of amastigotes inside macrophages. Liver, spleen, and lymph nodes were also studied as target organs to detect amastigotes. In addition, plasma was investigated for NO induction using Griess microassay.

Results

ASA increased NO production in plasma of both naïve and Leishmania test groups at the ultimate of the experimental period. A decline was observed in proliferation of amastigotes inside macrophages of test group when compared with control one. ASA reduced lesion size, inhibited Leishmania visceralisation in spleen, lymph node, and decreased hepato/splenomegaly in ASA treated animals.

Conclusions

Some antileishmanial effects of ASA by NO-modulation were indicated during systemic leishmaniasis in mice. Despite slight effects on lesion size, ASA decreased parasite visceralization in target organs and declined their proliferation inside macrophages. Therefore, ASA may be indicated to inhibit systemic leishmaniasis via NO pathway in mice model.  相似文献   
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178.

Background

The aim of this study was to apply the nested-PCR and bioassay methods in detection and genotyping of Toxoplasma gondii infection in provided sheep aborted fetus samples from Qazvin Province of Iran.

Methods

Eighteen sheep aborted fetal samples were studied by nested-PCR-RFLP, histopathological observation and microbiological assay. Bioassay in mice was carried out by inoculating the brain samples intraperitoneally.

Results

The results demonstrated the frequency of 66% infected sheep aborted fetal samples with T. gondii type one. Although we could not isolate any parasite from inoculated mice even after three passages, but it was confirmed histopathologically formation of cyst like bodies in prepared mice brain sections.

Conclusion

The results of the performed nested-PCR and formation of brain cyst in inoculated mice exhibited that T. gondii type one infection might be considered as one of the major causative agents for abortion in ewes.  相似文献   
179.
180.

Background

This study aimed to examine the effects of intermittent and continuous swimming training on muscle protein metabolism in neonatal alloxan-administered rats.

Methods

Wistar rats were used and divided into six groups: sedentary alloxan (SA), sedentary control (SC), continuous trained alloxan (CA), intermittent trained alloxan (IA), continuous trained control (CC) and intermittent trained control (IC). Alloxan (250 mg/kg body weight) was injected into newborn rats at 6 days of age. The continuous training protocol consisted of 12 weeks of swimming training in individual cylinder tanks while supporting a load that was 5% of body weight; uninterrupted swimming for 1 h/day, five days a week. The intermittent training protocol consisted of 12 weeks of swimming training in individual cylinder tanks while supporting a load that was 15% of body weight; 30 s of activity interrupted by 30 s of rest for a total of 20 min/day, five days a week.

Results

At 28 days, the alloxan animals displayed higher glycemia after glucose overload than the control animals. No differences in insulinemia among the groups were detected. At 120 days, no differences in serum albumin and total protein among the groups were observed. Compared to the other groups, DNA concentrations were higher in the alloxan animals that were subjected to continuous training, whereas the DNA/protein ratio was higher in the alloxan animals that were subjected to intermittent training.

Conclusion

It was concluded that continuous and intermittent training sessions were effective in altering muscle growth by hyperplasia and hypertrophy, respectively, in alloxan-administered animals.  相似文献   
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