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81.
Spinal cord injury (SCI) often leads to persistent functional deficits due to loss of neurons and glia and to limited axonal regeneration after injury. Here we report that transplantation of human dental pulp stem cells into the completely transected adult rat spinal cord resulted in marked recovery of hind limb locomotor functions. Transplantation of human bone marrow stromal cells or skin-derived fibroblasts led to substantially less recovery of locomotor function. The human dental pulp stem cells exhibited three major neuroregenerative activities. First, they inhibited the SCI-induced apoptosis of neurons, astrocytes, and oligodendrocytes, which improved the preservation of neuronal filaments and myelin sheaths. Second, they promoted the regeneration of transected axons by directly inhibiting multiple axon growth inhibitors, including chondroitin sulfate proteoglycan and myelin-associated glycoprotein, via paracrine mechanisms. Last, they replaced lost cells by differentiating into mature oligodendrocytes under the extreme conditions of SCI. Our data demonstrate that tooth-derived stem cells may provide therapeutic benefits for treating SCI through both cell-autonomous and paracrine neuroregenerative activities.  相似文献   
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Background/Aims: Laparoscopic surgery for periampullary disease is still a challenging operation. The aim of this study was to compare the perioperative outcomes of patients undergoing conventional pancreaticoduodenectomy (PD) with the outcomes of those undergoing laparoscopy-assisted PD. Methodology: A retrospective analysis was conducted on 51 consecutive patients who underwent laparoscopy-assisted or open PD for periampullary disease. Results: There were no significant differences in the preoperative demographic or clinical data of the two study groups. Although there were no significant differences in the operative time between the two study groups, blood loss in the laparoscopy-assisted PD group was significantly smaller than that in the open PD group. There were no significant differences in the occurrence of postoperative complications between the two groups. Conclusions: Laparoscopy-assisted PD is a feasible and safe surgical procedure that provides the advantages expected from a minimally invasive surgery including less blood loss.  相似文献   
84.
A large and increasing number of people in all over the world suffer from obesity, metabolic syndrome (MS) and type 2 diabetes mellitus (T2DM). Attenuation of the heat shock response (HSR), which was originally identified as a cellular defense mechanism, is one of the key factors involved in the deterioration of metabolic abnormalities. On the other hand, activating the HSR increases heat shock protein 72 (HSP72) expression and improves insulin resistance and glucose homeostasis in rodents and humans, possibly by inhibiting the activation of stress kinases such as c-jun terminal kinase (JNK) and inhibitor of kappa B kinase β (IKKβ). These approaches may also reduce inflammatory cytokine production and prevent the onset of atherogenic complications. This review focuses on the physiological effects of HSR in regulating insulin sensitivity and hyperglycemia, and the potential to target the HSR system for the treatment of MS and T2DM, as well as other cellular stress-related diseases.  相似文献   
85.
OBJECTIVE: To characterize the clinical, autoimmune, and genetic features in Japanese adult-onset diabetic patients with GAD autoantibodies. RESEARCH DESIGN AND METHODS: GAD autoantibodies (GADab) were screened in 4,980 diabetic patients with age of onset >20 years in the hospital-based Ehime Study, and the GADab-positive (GADab(+)) patients were then divided into two groups according to their insulin secretion and compared with nondiabetic subjects. The insulin-deficient state was defined as <0.33 nmol/l serum C-peptide (CPR) at 2 h postprandial or 6 min after a 1-mg glucagon load. RESULTS: GADab was detected in 188 (3.8%) of the 4,980 diabetic patients tested. Of these patients, 72 (38.3%) were classified as insulin deficient, 97 (51.6%) were classified as non-insulin deficient, and 19 (10.1%) were unclassified. The GADab(+) insulin-deficient patients were characterized by young age at onset of diabetes, low BMI, low maximum BMI, and high levels of HbA(1c). The prevalence of IA-2 autoantibodies and thyrogastric autoantibodies in the GADab(+) insulin-deficient patients were significantly higher than those in the GADab(+) non-insulin-deficient patients (P < 0.05). GADab(+) patients with insulin deficiency had increased frequencies of HLA DRB1*0405-DQB1*0401, *0802-*0302, and *0901-*0303 haplotypes, whereas the frequency of only HLA DRB1*0405-DQB1*0401 was increased in the case of GADab(+) non-insulin-deficient patients. Of note is the fact that the GADab(+) non-insulin-deficient group did not differ from healthy control subjects with respect to type 1 diabetes protective haplotype HLA DRB1*1502-DQB1*0601. A total of 13% of the GADab(+) patients with diabetes had genotypes comprising the DRB1*1501-DQB1*0602 or *1502-*0601 and were characterized by old age at onset of diabetes, high BMI, resistance to the insulin-deficient state, low titer of GADab, and low frequency of other organ-specific autoantibodies. CONCLUSIONS: We conclude that GADab(+) non-insulin-deficient patients differ from GADab(+) patients with insulin deficiency with respect to clinical characteristics, humoral autoimmunity to other organ-specific autoantibodies, as well as HLA class II genes.  相似文献   
86.
    
Dealing with the recent series of allogeneic hematopoietic stem cell transplantation (allo‐SCT) performed this decade, we reassessed the clinical impact of pretransplant surgical procedures (SP) for pulmonary lesions of invasive fungal disease (IFD) on subsequent transplant outcome. We focused on the clinical outcomes of seven patients with pulmonary IFD who underwent segmentectomy (n = 4), lobectomy (n = 2) or abscess incision with drainage only (n = 1), and compared results to those of 21 patients carrying pulmonary IFD who never underwent invasive SP before allo‐SCT. The rate of exacerbation of pulmonary lesions by 180 days after allo‐SCT did not differ significantly between groups (32.2% vs 42.9%, P = 0.69). Moreover, no significant differences in non‐relapse mortality (46.4% vs 42.3%, P = 0.93) or overall survival (53.6% vs 30.9%, P = 0.45) at 1 year were evident between groups. These results indicate that pretransplant SP for pulmonary lesions might have no survival benefit under the current antifungal prophylaxis or treatment modality.  相似文献   
87.
    
Ecthyma gangrenosum (EG) is a serious bacterial infection in immunocompromised patients. EG in transplant recipients is rarely reported and may go unrecognized, which may delay initiation of appropriate treatment. We report a case of EG in a pediatric heart transplant recipient who was treated successfully with antibiotics and surgical debridement.  相似文献   
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OBJECTIVE: De novo hepatitis B virus (HBV) infection after liver transplantation has recently been reported to be associated with donors without serum hepatitis B surface antigen (HbsAg) but with hepatitis B core antigen (anti-HBc). We elucidate the source of de novo HBV infection after liver transplantation by molecular evolutionary analysis. METHODS: The serum sample was obtained from a recipient who underwent living related liver transplantation. He was negative for all HBV-related serum markers before the transplantation. The recipient became seropositive for HBsAg at 6 months after transplantation. The liver tissue was obtained from a donor who was seronegative for HBsAg, but positive for anti-HBs and anti-HBc. RESULTS: HBV DNA was detected from the serum and liver tissue in a recipient and donor, respectively. A total of 5 clones each of small-S gene of HBV from the donor and recipient were sequenced. A phylogenetic tree analysis based on small-S gene revealed that all isolates derived from the recipient and donor were clustered together within a close range of evolutionary distances. These results indicated that HBV was transmitted by the liver graft from the donor. CONCLUSIONS: Molecular evolutionary analysis can be adopted for the study of the transmission route of viral infection via organ transplantation.  相似文献   
90.
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