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41.
Although there is evidence for distinct roles of myeloid dendritic cells (DCs [mDCs]) and plasmacytoid pre-DCs (pDCs) in regulating T cell-mediated adaptive immunity, the concept of functional DC subsets has been questioned because of the lack of a molecular mechanism to explain these differences. In this study, we provide direct evidence that maturing mDCs and pDCs express different sets of molecules for T cell priming. Although both maturing mDCs and pDCs upregulate the expression of CD80 and CD86, only pDCs upregulate the expression of inducible costimulator ligand (ICOS-L) and maintain high expression levels upon differentiation into mature DCs. High ICOS-L expression endows maturing pDCs with the ability to induce the differentiation of naive CD4 T cells to produce interleukin-10 (IL-10) but not the T helper (Th)2 cytokines IL-4, -5, and -13. These IL-10-producing T cells are T regulatory cells, and their generation by ICOS-L is independent of pDC-driven Th1 and Th2 differentiation, although, in the later condition, some contribution from endogenous IL-4 cannot be completely ruled out. Thus, in contrast to mDCs, pDCs are poised to express ICOS-L upon maturation, which leads to the generation of IL-10-producing T regulatory cells. Our findings demonstrate that mDC and pDCs are intrinsically different in the expression of costimulatory molecules that drive distinct types of T cell responses.  相似文献   
42.
OBJECTIVES: To describe the immunological responses and clinical outcome of coronavirus (SARS) infected healthcare workers (HCW) who had been administered with convalescent plasma as a treatment. METHODS: Convalescent plasma (500 mL) was obtained from each of three SARS patients and transfused into the three infected HCW. Donors were blood type O and seronegative for hepatitis B and C, HIV, syphilis and human T-cell lymphotropic virus types I and II (HTLV-I and -II). Serum antibody (IgG) titre was >640. Apharesis was performed with a CS 3000 plus cell separator followed by the forming of the convalescent phase plasma. As part of the routine check with donated plasma, the convalescent plasma was confirmed free of residual SARS-CoV by RT-PCR. Serial serum samples obtained from the recipients of the convalescent plasma were collected to undertake real-time quantitative RT-PCR for SARS-CoV for direct measurement of viral concentration. Specific immunoglobulin IgM and IgG concentrations were titrated using an antigen microarray developed in-house. RESULTS: Viral load dropped from 495 x 10(3), 76 x 10(3) or 650 x 10(3) copies/mL to zero or 1 copy/mL one day after transfusion. Anti-SARS-CoV IgM and IgG also increased in a time-dependent manner following transfusion. All three patients survived. One HCW became pregnant subsequently, delivering 13 months after discharge. Positive anti-SARS-CoV IgG was detected in the newborn. Passive transfer of anti-SARS-CoV antibody from the mother was considered as a possibility. CONCLUSIONS: All infected HCW whose condition had progressed severely and who had failed to respond to the available treatment, survived after transfusion with convalescent plasma.  相似文献   
43.
Effect of hyperbaric oxygen on endotoxin-induced lung injury in rats   总被引:1,自引:0,他引:1  
Oxygen therapy remains the main component of the ventilation strategy for treatment of patients with acute lung injury. Hyperbaric oxygen therapy (HBO(2)) is the intermittent administration of 100% oxygen at pressure greater than sea level and has been applied widely to alleviate a variety of hypoxia-related tissue injuries. The purpose of this study was to evaluate the effect of hyperbaric oxygen on acute lung injury induced by intratracheal spraying of lipopolysaccharide (LPS) in rats. Male Sprague-Dawley rats underwent implantation of a carotid artery catheter under general anesthesia. Aerosolized LPS was delivered twice into the lungs via intratracheal puncture. Animals were either breathing room air (n = 27) or subjected to hyperbaric oxygen (HBO(2)) exposure (n = 27) 1 h after LPS spraying. Acute lung injury was evaluated 5 h and 24 h later. Compared with the control group, intratracheal spraying of LPS caused profound hypoxemia, greater wet/dry weight ratio (W/D) of the lung (5.67 +/- 0.22 vs. 4.98 +/- 0.19), and higher protein concentration (1706 +/- 168 vs. 200 +/- 90 mg/L) and LDH activity (129 +/- 30 vs. 46 +/- 15, mAbs/min) in bronchoalveolar lavage (BAL) fluid. Intratracheal spraying of LPS also caused significant WBC sequestration in the lung tissue. HBO2 treatment significantly reverted hypoxemia, reduced lung injury measures evaluated at 5 and 24 h, and enhanced 24-h animal survival rate (chi = 5.08, P = 0.024). The malondialdehyde (MDA) concentrations in lung tissue and serum were both increased after LPS spraying. Neither single HBO(2) therapy nor five sequential daily treatments enhanced MDA production in lung tissue or serum. Our results suggested that hyperbaric oxygen might reduce acute lung injury caused by intratracheal spraying of LPS in rats. This treatment modality is not associated with enhancement of oxidative stress to the lung.  相似文献   
44.
Systemic lupus erythematosus (SLE) is an autoimmune disease, involving multiple organs. Diverse manifestations may obscure the diagnosis and confuse our thinking process, especially when few clues are present at the beginning. Serositis is one of the various presentations, and the presence of lupus erythematosus (LE) cell in body fluid may be a hint for the final diagnosis of SLE. Herein, we present a young female patient diagnosed of SLE with initial presentation of lupus peritonitis. Finding of LE cell in ascites prompted us for immunologic survey. Diagnosis of SLE was confirmed with high titer of anti-nuclear antibody and antibody to double-stranded DNA. Cytologic examination of body fluid is mainly useful in detecting malignant cells, but high specificity of this marker aids in early diagnosis of SLE.  相似文献   
45.
46.

AIMS

We aimed to assess the clinical effectiveness of oral vs. intravenous (i.v.) regular-dose proton pump inhibitor (PPI) after endoscopic injection of epinephrine in patients with peptic ulcer bleeding.

METHODS

Peptic ulcer patients with active bleeding, nonbleeding visible vessels, or adherent clots were enrolled after successful endoscopic haemostasis achieved by epinephrine injection. They were randomized to receive either oral rabeprazole (RAB group, 20 mg twice daily for 3 days) or i.v. omeprazole (OME group, 40 mg i.v. infusion every 12 h for 3 days). Subsequently, the enrolled patients receive oral PPI for 2 months (rabeprazole 20 mg or esomeprazole 40 mg once daily). The primary end-point was recurrent bleeding up to 14 days. The hospital stay, blood transfusion, surgery and mortality within 14 days were compared as well.

RESULTS

A total of 156 patients were enrolled, with 78 patients randomly allocated in each group. The two groups were well matched for factors affecting the clinical outcomes. Primary end-points (recurrent bleeding up to 14 days) were reached in 12 patients (15.4%) in the OME group and 13 patients (16.7%) in the RAB group [95% confidence interval (CI) of difference −12.82, 10.22]. All the rebleeding events occurred within 3 days of enrolment. The two groups were not different in hospital stay, volume of blood transfusion, surgery or mortality rate (1.3% of the OME group and 2.6% of the RAB group died, 95% CI of difference −5.6, 3.0).

CONCLUSIONS

Oral rabeprazole and i.v. regular-dose omeprazole are equally effective in preventing rebleeding in patients with high-risk bleeding peptic ulcers after successful endoscopic injection with epinephrine.  相似文献   
47.
Varicella arthritis diagnosed by polymerase chain reaction.   总被引:1,自引:0,他引:1  
We report a 2-year-old girl who developed acute arthritis of the left knee 4 days after the onset of a typical varicella infection. She was first thought to have pyogenic arthritis caused by Staphylococcus aureus. Accordingly, oxacillin was administered upon hospitalization. On the third day after hospitalization, bacterial cultures of the synovial fluid and blood showed no growth and oxacillin was discontinued. Although a viral culture of the synovial fluid for varicella-zoster virus (VZV) was negative, varicella DNA was identified by means of polymerase chain reaction (PCR) with VZV-specific primers. The patient recovered spontaneously. To differentiate this condition from septic arthritis is important. PCR is a sensitive technique that can demonstrate the presence of VZV DNA in synovial fluid, even if viral cultures are negative.  相似文献   
48.
49.
The Nd-YAG laser has good tissue penetration and coagulation effects thus has become an important weapon for photoresection of tracheobronchial obstructive lesions since 1980.Treatment of benign lesions including benign tumors and scar tissues using the Nd-YAG laser has good results. In the treatment of malignant tumors however, it has a lower effectivity rate when compared to benign lesions. From July 1984 to September 1995, a total of 65 patients were treated with Nd-YAG laser for tracheobronchial obstruction. There were 32 (49%) malignant tumors and 33 (51%) benign lesions. 116 resections were performed in 48 patients using the non-contact Nd-YAG laser (MBB, Medilas 2) before 1992. Thereafter, another 41 resections were performed in 17 cases using contact Nd-YAG laser (SLT, CL-X). The overall effectivity rate was 60%. The effectivity rate for benign lesions was 81.3% and 39.4% for malignant tumor. The effectivity rate between non-contact and contact Nd-YAG laser was not significantly different.  相似文献   
50.
BackgroundLaparoscopic Roux-en-Y gastric bypass (LRYGB) has been shown to improve both the health and the quality of life of morbidly obese patients. We compared the efficacy and safety of using a team approach to LRYGB versus an individual surgeon at a medical center.MethodsData were collected from 200 consecutive patients undergoing LRYGB for morbid obesity from August 2005 to February 2008. Groups 1 and 2 included 50 patients each who underwent surgery and were cared for by the same surgeon. Group 3 included the next 100 consecutive patients, who underwent LRYGB by the same surgeon but who were cared for by a dedicated bariatric team.ResultsFor the 76 men (38%) and 124 women (62%) in the study, the excess weight loss at 1 and 3 months of follow-up did not differ; however, it was significantly different at 6 and 12 months. At the mean follow-up period, 30% of group 1, 6% of group 2, and 8% of group 3 had experienced complications. Most complications in group 1 occurred early and were related to the surgical technique; however, in groups 2 and 3, the complications related to the technique were markedly reduced. Men were 4.57 times as likely as women to experience complications related to bariatric surgery.ConclusionA team-based approach is a better option for patients undergoing LRYGB than care by a single surgeon. With an experienced bariatric surgeon, the team approach resulted in shorter operative times and shorter hospital stays, with the same rate of complications.  相似文献   
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