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81.
PurposeCytomegalovirus (CMV) infection is known to be the most frequently viral infection among patients after liver transplantation. This is especially true in pediatric living-donor liver transplantation because the recipients have often not been infected with CMV and postoperative primary infection with CMV frequently occurs.Patients and MethodsOf 93 patients who underwent pediatric liver transplantation at our department, 33 patients (36.3%) were diagnosed with CMV infection using the antigenemia method (C7-HRP). Retrospective review and statistical analysis were conducted to confirm risk factors of post-transplantation CMV infection.ResultPositive lymphocytes were diagnosed between postoperative days 8 and 111 after transplantation. Ganciclovir or foscavir were administrated to 21 patients. The other 10 patients who had one positive lymphocyte were observed and the cell disappeared on follow-up examination. We did not observe any cases of positive lymphocytes with C7-HRP in patients who received a graft from a CMV antibody?negative donor. Independent predictors associated with CMV infection in the multivariable analysis were administration of OKT3 and grafts from CMV antibody?positive donors.ConclusionIn CMV infection after pediatric liver transplantation, cases with CMV antibody?positive donors and with OKT3 administration for acute rejection are considered high risk, and cases with CMV antibody?negative donors are considered low risk.  相似文献   
82.
Rational treatment for neoplasms of the duodenal papilla (NDPs) is still controversial, especially for early stage lesions. Total papillectomies are indicated in patients expected to have adenomas, adenocarcinoma in an adenoma, or mucosal adenocarcinomas with no lymph node metastases. However, the preoperative pathological evaluation of NDPs is still challenging and often inaccurate, mainly because of the complicated anatomical structures involved and the possibility of an adenocarcinoma in an adenoma. Herein, we introduce a new method of total papillectomy, the extraduodenal papillectomy (ExDP). In this method, papillectomy is undertaken from outside of the duodenum, instead of resection from the inside through a wide incision of the duodenal wall as is done in conventional transduodenal papillectomy (TDP). The advantages of ExDP are precise and deeper cutting of the sphincter and shorter exploration time of the tumor compared to conventional TDP. We demonstrate three representative patients, all of whom had an uneventful postoperative course. One of them subsequently underwent a pylorus preserving pancreatoduodenectomy after detailed postoperative pathological evaluation. Including that patient, no recurrence has occurred with 37–46 months of follow-up. In conclusion, ExDP is regarded as a “total biopsy” for early stage borderline lesions and a feasible, less demanding alternative method for the treatment of NDPs.  相似文献   
83.
On 5 November 2020, a confirmed outbreak due to an H5N8 highly pathogenic avian influenza virus (HPAIV) occurred at an egg-hen farm in Kagawa prefecture (western Japan). This virus, A/chicken/Kagawa/11C/2020 (Kagawa11C2020), was the first HPAI poultry isolate in Japan in 2020 and had multiple basic amino acids—a motif conferring high pathogenicity to chickens—at the hemagglutinin cleavage site. Mortality of chickens was 100% through intravenous inoculation tests performed according to World Organization for Animal Health criteria. Phylogenetic analysis showed that the hemagglutinin of Kagawa11C2020 belongs to clade 2.3.4.4B of the H5 Goose/Guangdong lineage and clusters with H5N8 HPAIVs isolated from wild bird feces collected in Hokkaido (Japan) and Korea in October 2020. These H5N8 HPAIVs are closely related to H5N8 HPAIVs isolated in European countries during the winter of 2019–2020. Intranasal inoculation of chickens with 106 fifty-percent egg infectious doses of Kagawa11C2020 revealed that the 50% chicken lethal dose was 104.63 and the mean time to death was 134.4 h. All infected chickens demonstrated viral shedding beginning on 2 dpi—before clinical signs were observed. These results suggest that affected chickens could transmit Kagawa11C2020 to surrounding chickens in the absence of clinical signs for several days before they died.  相似文献   
84.
Engagement of the mast cell high-affinity receptor for immunoglobulin E (IgE), FcRI, induces tyrosine phosphorylation of Syk, a non-receptor tyrosine kinase, that has been demonstrated as critical for degranulation. Herein we describe a synthetic compound, ER-27319, as a potent and selective inhibitor of antigen or anti-IgE-mediated degranulation of rodent and human mast cells. ER-27319 affected neither Lyn kinase activity nor the antigen-induced phosphorylation of the FcRI but did effectively inhibit the tyrosine phosphorylation of Syk and thus its activity. As a consequence, tyrosine phosphorylation of phospholipase C-γ1, generation of inositol phosphates, release of arachidonic acid, and secretion of histamine and tumor necrosis factor α were also inhibited. ER-27319 did not inhibit the anti-CD3-induced tyrosine phosphorylation of phospholipase C-γ1 in Jurkat T cells, demonstrating a specificity for Syk-induced signals. In contrast the tyrosine phosphorylation and activation of Syk, induced by in vitro incubation with the phosphorylated immunoreceptor tyrosine-based activation motif (ITAM) of FcRI γ subunit or by antigen activation of RBL-2H3 cells, was specifically inhibited by ER-27319. However, when ER-27319 was added to immunoprecipitated Syk, derived from activated cells, no effect was seen on Syk activity. ER-27319 did not inhibit the tyrosine phosphorylation of Syk induced by activation in the presence of Igβ ITAM or the anti-IgM-induced phosphorylation of Syk in human peripheral B cells. Therefore, ER-27319 selectively interferes with the FcRI γ phospho-ITAM activation of Syk in vitro and in intact cells. These results confirm the importance of Syk in FcRI-mediated responses in mast cells and demonstrate the mast cell selectivity and therapeutic potential of ER-27319 in the treatment of allergic disease.  相似文献   
85.
Summary The effects of cicletanine, a new antihypertensive agent, on the prostaglandin-kallikrein system and the reninangiotensin system were studied. A single oral dose of 200 mg cicletanine or placebo was administered to 9 healthy male volunteers, with samples of blood and urine obtained before and 2 hours after drug administration. Cicletanine increased the urine flow, urinary excretion of sodium, and fractional excretion of sodium by 47%, 115%, and 104%, respectively. While the excretion of 6-keto-prostaglandin-F1 was enhanced significantly, urinary excretion of thromboxane-B2, prostaglandin-E2, and kallikrein were unchanged. Cicletanine also did not alter plasma renin activity, plasma aldosterone concentration, or creatinine clearance. These observations suggest that cicletanine may suppress sodium reabsorption at the nephron, and it may stimulate prostacyclin generation with no effect on that of thromboxane-A2. Thus cicletanine may be beneficial in the management of cardiovascular disorders in which the equilibrium between prostacyclin and thromboxane is disturbed.  相似文献   
86.
3,5,3'-Triiodo-L-thyronine (T3) potentiates apoptosis during the all-trans-retinoic acid-induced differentiation of promyeloleukemic HL-60 cells. We examined whether the retinoid receptor-specific thyroid hormone action is present during differentiation of HL-60 cells in this study. We used two distinct retinoid receptor agonists. T3 potentiates G1 arrest induced by Am80, a retinoic acid receptor (RAR)-specific agonist, but had no effect on G1 arrest induced by HX600, a retinoid x receptor (RXR)-specific agonist. Am80 alone induces the apoptosis, and T3 enhances it. Although HX600 alone fails to increase the apoptotic fraction, T3 enables the compounds to induce apoptosis. Am80-induced expression of CD11b, a marker for the differentiation, is enhanced by T3. However, T3 or HX600 or both do not affect the expression of CD11b. T3 does not alter the amount of mRNAs of various members of the bcl-2 family. T3, however, enhances the Am80-induced expression of bfl-1 and suppression of bcl-2. In contrast, T3 does not alter either bfl-1 and bcl-2 expression in the presence of HX600. Our observations suggest that cooperative action of T3 with an RXR-specific ligand is different from that with an RAR ligand in cellular apoptotic regulation and that thyroid hormone may be available as a chemotherapeutic agent in acute leukemia.  相似文献   
87.
88.
We report a 71-year-old man who had undergone pylorus-preserving pancreatoduodenectomy (PPPD) using PPPD-IV reconstruction for cholangiocarcinoma. For 6 years thereafter, he had suffered recurrent cholangitis, and also a right liver abscess (S5/8), which required percutaneous drainage at 9 years after PPPD. At 16 years after PPPD, he had been admitted to the other hospital because of acute purulent cholangitis. Although medical treatment resolved the cholangitis, the patient was referred to our hospital because of dilatation of the intrahepatic biliary duct (B2). Peroral double-balloon enteroscopy revealed that the diameter of the hepaticojejunostomy anastomosis was 12 mm, and cholangiography detected intrahepatic stones. Lithotripsy was performed using a basket catheter. At 1 year after lithotripsy procedure, the patient is doing well. Hepatobiliary scintigraphy at 60 minutes after intravenous injection demonstrated that deposit of the tracer still remained in the upper afferent loop jejunum. Therefore, we considered that the recurrent cholangitis, liver abscess, and intrahepatic lithiasis have been caused by biliary stasis due to nonobstructive afferent loop syndrome. Biliary retention due to nonobstructive afferent loop syndrome may cause recurrent cholangitis or liver abscess after hepaticojejunostomy, and double-balloon enteroscopy and hepatobiliary scintigraphy are useful for the diagnosis of nonobstructive afferent loop syndrome.Key words: Nonobstructive afferent loop syndrome, Biliary stasis, Hepaticojejunostomy, Hepatobiliary scintigraphy, Double-balloon enteroscopyIt has been reported that cholangitis occurs in between 6.7% and 14.3% of postoperative pancreatoduodenectomy (PD).1 Most cases of cholangitis originate due to biliary stasis, which is broadly caused by either anastomotic or nonanastomotic stenosis. In many cases, anastomotic stenosis is accompanied by intrahepatic biliary duct dilatation and obstructive jaundice, making early diagnosis and treatment possible.23 On the other hand, nonanastomotic stenosis, including those of afferent loop syndrome, is performed as a conservative treatment for unexplained fever and cholangitis. However, in many cases, the cause remains unidentified, thereby causing this condition to repeat itself. Since cholangitis can at times be fatal, it is therefore important to identify the cause.It has been reported that afferent loop syndrome occurs in around 13% of postoperative PD patients.4 Afferent loop syndrome is generally caused by mechanical occlusion due to the recurrence or metastasis of cancer,46 adhesion,78 torsion,9 internal hernia,10 enterolithiasis,1112 etc., and thereafter, leads to a syndrome associated with acute abdominal symptom or acute cholangitis. On the other hand, nonobstructive afferent loop syndrome may also be caused by biliary stasis due to jejunal motility failure or the length of the blind end or jejunum, and thereafter, leads to acute cholangitis, liver abscess, and the formation of enterolithiasis and intrahepatic stones. Nonobstructive afferent loop syndrome occurs in around 37% of all of the afferent loop syndrome,1213 but few cases have actually been reported.We herein report a rare case in which the patient experienced recurrent cholangitis and liver abscess by biliary stasis due to nonobstructive afferent loop syndrome after pylorus-preserving pancreatoduodenectomy (PPPD) for cholangiocarcinoma.  相似文献   
89.
Most inhabitants of Tohoku district suffer from chronic fatigue after the 2011 Great East Japan Earthquake. Chronic fatigue following disasters may lead to serious illness, even death. Posttraumatic growth appears to counteract fatigue. We predicted that the chronic fatigue would be inversely related to the posttraumatic growth factor “relating to others,” as represented by mutual helping and a strong sense of connection with humanity. Young 59 healthy volunteers, residing in Miyagi prefecture, were recruited 3 months after the disaster. We measured the subjects? total scores on the Japanese version of the Checklist Individual Strength questionnaire (CIS), the Trait Anxiety (T-A) subscale of the State–Trait Anxiety Inventory (STAI), the Center for Epidemiologic Studies Depression Scale (CES-D), and four subscores on the posttraumatic growth inventory (PTGI). Stepwise regression analyses were conducted with score on the CIS as the dependent variable and other scores as independent variables. Scores on the “relating to others” factor of the PTGI showed a significant negative relationship with the CIS score, whereas the scores on the T-A subscale of the STAI and the CES-D were positively related to the CIS score. Human ties and mutual help were negatively related to the degree of the chronic fatigue.  相似文献   
90.
The NLRP3 inflammasome is a molecular complex that translates signals from pathogens and tissue damage into inflammatory responses, and plays crucial roles in numerous neurological diseases. Activation of the NLRP3 inflammasome leads to caspase-1 dependent cleavage of pro-IL-1β to form mature IL-1β. By acting on the P2X7 purinergic receptor, extracellular ATP is one of the major stimuli that activates the NLRP3 inflammasome. Although microglia express multiple purinergic receptors, their roles in inflammasome-mediated inflammation are largely unknown. We studied the role of the P2Y12 receptor, a metabotropic P2Y receptor enriched in microglia, on inflammation in vitro. Inhibition of the microglial P2Y12 receptor by PSB0739 or siRNA knockdown suppressed IL-1β release. P2Y12 receptor-deficient microglia displayed markedly attenuated IL-1β mRNA expression and release. P2Y12 receptor blockade also suppressed IL-6 production. Both IL-1β and IL-6 responses were augmented by extracellular ADP or ADP-βS and were abrogated by PSB0739. Mechanistically, ADP-βS potentiated NF-κB activation. In addition, ADP altered mitochondrial membrane potential in combination with ATP and increased the number of caspase-1 positive cells through the P2Y12 receptor. These results elucidate a novel inflammatory mechanism by which extracellular ADP acts on the P2Y12 receptor to activate NF-κB and the NLRP3 inflammasome to enhance microglial inflammation.  相似文献   
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