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131.
The human liver contains significant numbers of innate immune cells, such as natural killer (NK) cells and natural killer T (NKT) cells, which express both T-cell receptors and NK-cell receptors simultaneously. It has been suggested that the innate immune system plays a crucial role in the liver. In this report, the distribution of NK and NKT cells in the liver and peripheral blood of two patients with drug-induced fulminant hepatic failure (FHF) who had undergone living donor liver transplantation was examined. In both the liver and peripheral blood, the proportions of NK and NKT cells markedly decreased compared with those in healthy donors. It was also revealed that, unlike murine NKT cells, human CD56(+) T cells and CD57(+) T cells did not constitutively express CD28, which is one of the important costimulatory molecules on T cells. Additionally, the residual CD56(+) T cells and CD57(+) T cells in the patients expressed more CD28 than in controls. This result suggests that NKT cells might be more activated in FHF. Although the accumulation of further cases is required, it is suggested that both NK and NKT cells might be involved in hepatic injury in FHF.  相似文献   
132.
We present a patient who underwent sibling allogeneic BMT because of refractory Ph+ve ALL and remained BCR-ABL-positive after marrow grafting. Haemopoietic precursor cells were predominantly BCR-ABL-negative and of donor origin. In T cells an exclusively donor genotype was demonstrated. Despite donor leucocyte infusion (DLI), 20 weeks after BMT BCR-ABL fusion mRNA increased in semiquantitative polymerase chain reaction and leukaemic infiltration of the patient's bone marrow was seen. After a second course of DLI the patient achieved sustained molecular remission but he developed severe graft-versus-host disease (GvHD) and died from bacterial sepsis 9 months after DLI.  相似文献   
133.
Abstract: Background and objectives. Hepatitis B virus (HBV) has been transmitted by tissue transplantation. In order to reduce the risk of HBV transmission, testing for antibody to HBV core antigen (anti‐HBc) is used in addition to testing for hepatitis B surface antigen (HBsAg) in many blood centers and tissue banks. Design and methods. We retrospectively analyzed the results of HBV assays in tissue donors. All tissue donors were tested for HBsAg and anti‐HBc. All anti‐HBc positive sera were tested for the antibody to HBsAg (anti‐HBs). From July 2006, an HBV nucleic acid testing (NAT) assay was also performed. Results. A total of 6855 tissue donors from January 1999 till July 2007 were tested for HBV assays: 4756 women and 2099 men. Positive HBsAg was found in 23 (0.36%) living donors, while no multiorgan or cord blood (CB) donor was found to be positive for HBsAg. Positive anti‐HBc was found in 80 multiorgan donors (12.94%), 599 living donors (17.84%), and 103 CB donors (3.57%) (P<0.005), while isolated anti‐HBc was found in 12 multiorgan (1.94%), in 126 living tissue donors (3.75%), and in 8 CB donors (0.28%). A total of 1310 donors were analyzed for single‐sample DNA HBV NAT assay. Discussion. We consider that anti‐HBc and NAT assays must both still be performed in addition to HBsAg assay for HBV screening in tissue donors. All these tests will be useful in order to define an algorithm for safe and efficient management of the tissue bank.  相似文献   
134.
Spontaneous bacterial peritonitis (SBP) is a common cause of morbidity and mortality in patients with advanced cirrhosis and portal hypertension. While gram-negative rods and Enterococcus species are the common offending organisms, Salmonella has also been recognized as a rare and atypical offending organism. Atypical features of Salmonella SBP include both its occurrence in cirrhotic patients with immunosuppressive state and its lack of typical neutroascitic response. Diagnosis is often delayed as it requires confirmation from ascitic fluid culture. We report a case of Salmonella SBP occurring in a patient with decompensated cryptogenic cirrhosis with concurrent low-grade non-Hodgkin lymphoma and prior treatment with rituximab. Physicians should be aware of the atypical presentation, especially in cirrhotic patients who are immunosuppressed.  相似文献   
135.
AIM: Autologous blood donation (ABD) is mainly used to reduce the use of banked blood. In fact, ABD can be regarded as acute blood loss. Would ABD 2-3 d before operation affect the CVP level and subsequently result in less blood loss during liver resection was to be determined. METHODS: Eighty-four patients undergoing living donor left hepatectomy were retrospectively divided as group Ⅰ (GI) and group Ⅱ (Gil) according to have donated 250-300 mL blood 2-3 d before living donor hepatectomy or not. The changes of the intraoperative CVP, surgical blood loss, blood products used and the changes of perioperative hemoglobin (Hb) between groups were analyzed and compared by using Mann-Whitney U test. RESULTS: The results show that the intraoperative CVP changes between GI (n = 35) and GII (n = 49) up to graft procurement were the same, subsequently the blood loss, but ABD resulted in significantly lower perioperative Hb levels in GI. CONCLUSION: Since none of the patients required any blood products perioperatively, all the predonated bloods were discarded after the patients were discharged from the hospital. It indicates that ABD in current series had no any beneficial effects, in term of cost, lowering the CVP, blood loss and reduce the use of banked blood products, but resulted in significant lower Hb in perioperative period.  相似文献   
136.
Liver transplantation is a radical therapy for end-stage liver disease. The severe shortage of transplantable organs is, however, a big problem, not only in liver transplantation but also other organ transplants. Although in Japan, transplantation of organs obtained from brain-dead donors (BDD) has been allowed since October 1997, to date only 27 BDD have been obtained. It has become difficult to procure liver grafts from BDD, therefore we must use liver grafts from living donors. The living-donor liver transplantation (LDLT) program started in 1990 in Japan, and is still the major form of liver transplantation because of the scarcity of cadaveric donors. In the Department of Transplant Surgery, Kyoto Hospital (Kyoto, Japan), the accumulated number of LDLT cases exceeded 955 up to October 2003. In order to perform LDLT under safer conditions, apheresis plays a major role in Japan due to the prevalence of LDLT where later retransplantation is difficult. Clinical indications of apheresis for LDLT are mainly use as a bridge before transplantation, and liver support after transplantation. We describe the effect of apheresis therapy for LDLT patients with nephritic and hepatic problems.  相似文献   
137.
138.
The functional relevance of polymorphisms outside the peptide binding groove of HLA molecules is poorly understood. Here we have addressed this issue by studying HLA-DP3, a common antigen relevant for functional matching algorithms of unrelated hematopoietic stem cell transplantation (HSCT) encoded by two transmembrane (TM) region variants, DPB1*03:01 and DPB1*104:01. The two HLA-DP3 variants were found at a overall allelic frequency of 10.4% in 201 volunteer stem cell donors, at a ratio of 4.2:1. No significant differences were observed in cell surface expression levels of the two variants on B lymphoblastoid cell lines (BLCL), primary B cells or monocytes. Three different alloreactive T cell lines or clones showed similar levels of activation marker CD107a and/or CD137 upregulation in response to HLA-DP3 encoded by DPB1*03:01 and DPB1*104:01, either endogenously on BLCL or after lentiveral-vector mediated transfer into the same cellular background. These data provide, for the first time, direct evidence for a limited functional role of a TM region polymorphism on expression and allorecognition of HLA-DP3 and are compatible with the notion that the two variants can be considered as a single functional entity for unrelated stem cell donor selection.  相似文献   
139.
Four conjugated D‐π‐A copolymers, P1 – P4 , based on 11,12‐difluorodibenzo[a,c]phenazine as an acceptor unit, benzodithiophene (BDT) with an alkoxy side chain ( P1 and P2 ) or thiophene‐conjugated side chain ( P3 and P4 ) as a donor unit, and thiophene π‐bridges, are designed and synthesized to investigate the effect of the side‐chain nature and position on the photovoltaic performance of the conjugated polymer donor materials in polymer solar cells (PSCs). It is found that the copolymers of P3 and P4 with thiophene conjugated side chains on the BDT unit demonstrate broader absorption and better photovoltaic performance than that of P1 and P2 with alkoxy side chains on the BDT unit. The photovoltaic performance of P1 and P3 with an alkyl side chain on the thiophene π‐bridge close to the acceptor unit is improved over that of P2 and P4 with an alkyl side chain on the thiophene π‐bridge close to the donor unit, due to the lower steric hindrance of P1 and P3 . The results indicate that side‐chain engineering is very important for improving the photovoltaic performance of conjugated polymer donor materials.

  相似文献   

140.
Cross-sectional studies of the prevalence of anti-SARS-CoV-2 in representative groups are routinely used for surveillance of public health in Norway. The group of blood donors is easily accessible to provide an estimate over the infection prevalence. Repeated testing of returning donors also generates data about the duration of the antibody response following infection and vaccination.The aim of the current study was to provide updated information about the development of the pandemic in the blood donor population, and to estimate the number of asymptomatic donors visiting the blood center, in an effort to evaluate the measures to prevent virus spreading between donors and staff.In the two main blood banks in the Oslo area, all blood donors were offered antibody testing for a period of three months. Almost 12,000 donors were tested, and the mean weekly prevalence of antibody positive donors due to infection was 2.7 % (varied from 2.1 to 4.0 %). The number of donors presenting following vaccination was 810 (6.9 %). An average of 38 % of the infections had been asymptomatic, and 31 % of the antibody-positive donors were unaware of having been infected.In conclusion, the proportion of blood donors seropositive for anti-SARS-CoV-2 in our blood centers was stable whereas the number of vaccinated blood donors rapidly increased. This indicates that the virus spreading in the third wave of infection in the Oslo area mainly happened in groups underrepresented as blood donors. Health care workers prioritized for early vaccination may be overrepresented in the study period.  相似文献   
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