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A massive pulmonary hemorrhage in patients with liver cirrhosis is a life‐threatening complication that may result in a contraindication of a liver transplantation because of its high mortality rate. Herein, we present two infant biliary atresia cases that successfully underwent an LDLT that was followed by intensive respiratory care for the pretransplant massive pulmonary hemorrhage. Both cases exhibited severe respiratory failure (minimum PaO2/FiO2; 46 mmHg and 39 mmHg, respectively). To arrest the bleeding, we applied a very high positive pressure ventilation treatment (maximum PIP/PEEP; 38/14 cmH2O and 55/15 cmH2O, respectively), plasma exchange, several FFP transfusions, and recombinant factor VIIa via intrapulmonary administration. In addition, we used CHDF treatment, applied HFOV transiently, and treated the patient with inhalation of nitric oxide. Although we prepared ECMO for intra‐operative use, both cases were successfully managed with conventional mechanical ventilation without using ECMO, which may have worsened the pulmonary hemorrhage due to the use of an anticoagulant. Use of an excessive positive pressure management, although it poses a risk for barotrauma, could be acceptable to arrest the pulmonary bleeding in selected cases of liver failure patients who have no time remaining before LDLT.  相似文献   
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We herein present the case of a four‐yr‐old boy with PA who developed AMR after ABO‐incompatible LDLT despite undergoing B cell desensitization using rituximab. Although the CD19+ lymphocyte count decreased to 0.1% nine days after the administration of rituximab, he developed a high fever which was accompanied by arthralgia due to a streptococcal infection 13 days after rituximab prophylaxis. After the clearance of the infection, he underwent ABO‐incompatible LDLT 36 days after the administration of rituximab. The CD19+ lymphocyte count just prior to LDLT was 1.2%. He developed AMR five days after LDLT, and the antidonor‐type IgM and IgG antibody titers increased to 1:1024 and 1:1024, respectively. He was treated by plasma exchange, IVIG, steroid pulse therapy, and rituximab re‐administration; however, his liver dysfunction continued. Despite intensive treatment, he died due to complicated abdominal hernia, acute renal failure, and ARDS. This case suggests that a streptococcal infection may induce the activation of innate immune responses; thus, additional desensitization therapy should be considered prior to ABO‐incompatible LDLT if B cell reactivation is suspected.  相似文献   
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Fetuin is a biocompatible plasma protein and strongly enhances phagocytosis of bacteria, DNA and apoptotic cells by peripheral blood cells such as monocytes, macrophages and dendritic cells. We developed a novel gene delivery system: ternary complexes constructed with pDNA, polyethylenimine (PEI) and fetuin. Without covalent binding, fetuin was able to coat pDNA–PEI complexes, and stable anionic nanoparticles formed at a weight ratio greater than 30. Optimised pDNA–PEI–fetuin complexes significantly decreased the cytotoxicity of pDNA–PEI complexes in the melanoma cell line B16F10. Furthermore, the pDNA–PEI–fetuin complexes had higher transgene efficiency compared to that of commercial lipofectin previously reported in B16F10 cells despite an anionic surface. The pDNA–PEI–fetuin complexes did not agglutinate with erythrocytes. The pDNA–PEI–fetuin complexes had high gene expression in the spleen after intravenous administration in mice. Thus, the pDNA–PEI–fetuin complexes were a useful in vivo gene delivery system with tropism for the spleen.  相似文献   
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Obesity is characterized by hyperinsulinemia, hyperleptinemia, and an increase in islet volume. While the mechanisms that hasten the onset of diabetes in obese individuals are not known, it is possible that the adipose-derived hormone leptin plays a role. In addition to its central actions, leptin exerts biological effects by acting in peripheral tissues including the endocrine pancreas. To explore the impact of disrupting leptin signaling in the pancreas on beta cell growth and/or function, we created pancreas-specific leptin receptor (ObR) KOs using mice expressing Cre recombinase under the control of the pancreatic and duodenal homeobox 1 (Pdx1) promoter. The KOs exhibited improved glucose tolerance due to enhanced early-phase insulin secretion, and a greater beta cell mass secondary to increased beta cell size and enhanced expression and phosphorylation of p70S6K. Similar effects on p70S6K were observed in MIN6 beta cells with knockdown of the ObR gene, suggesting crosstalk between leptin and insulin signaling pathways. Surprisingly, challenging the KOs with a high-fat diet led to attenuated acute insulin secretory response to glucose, poor compensatory islet growth, and glucose intolerance. Together, these data provide direct genetic evidence, from a unique mouse model lacking ObRs only in the pancreas, for a critical role for leptin signaling in islet biology and suggest that altered leptin action in islets is one factor that contributes to obesity-associated diabetes.  相似文献   
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Vascular complications of distal femoral fractures are rare but can have disastrous consequences if not recognised and treated promptly. We present the case of a 55-year-old woman who developed a pseudoaneurysm of the superficial femoral artery after osteosynthesis to repair a supracondylar femoral fracture. Eight weeks after surgery, swelling of the right thigh persisted and was accompanied by severe pain. Enhanced computed tomography revealed a pseudoaneurysm in the medial aspect of the affected thigh. Open surgical repair was performed by direct arterial suture. Although the true aetiology of the development of the pseudoaneurysm is unknown, a bony fragment from the reduction manoeuvre may have damaged the adventitia of the superficial femoral artery. In cases of continuous thigh swelling after osteosynthesis to repair a supracondylar femoral fracture, a diagnosis of pseudoaneurysm should be considered and treatment should be initiated immediately.  相似文献   
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Intersphincteric resection (ISR) is an ideal technique that preserves the anus, regardless of whether the internal anal sphincter is removed. However, it is difficult to dissect the anterior wall of the rectum from the adjacent organs. We herein describe a safe and useful ISR technique which draws out the rectum through the anus. The intersphincteric space (ISS) between the internal and external anal sphincter muscles was first transabdominally dissected. Next, the transanal dissection was advanced into the ISS bilaterally from the posterior side without dissecting the anterior wall of the anal canal, and the sigmoid colon and rectum were drawn out through the anus. Dissection between the anterior wall of the rectum and prostate/vagina could be easily performed under direct vision. This technique enables the dissection without any risk of a positive surgical margin or unexpected bleeding, and avoids injury to adjacent organs. This technique seems to be a safe and useful dissection technique for approaching the anterior wall of the anal canal.  相似文献   
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