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Tick-borne encephalitis virus (TBEV) is an emerging human pathogen that causes potentially fatal disease with no specific treatment. Mouse monoclonal antibodies are protective against TBEV, but little is known about the human antibody response to infection. Here, we report on the human neutralizing antibody response to TBEV in a cohort of infected and vaccinated individuals. Expanded clones of memory B cells expressed closely related anti-envelope domain III (EDIII) antibodies in both groups of volunteers. However, the most potent neutralizing antibodies, with IC50s below 1 ng/ml, were found only in individuals who recovered from natural infection. These antibodies also neutralized other tick-borne flaviviruses, including Langat, louping ill, Omsk hemorrhagic fever, Kyasanur forest disease, and Powassan viruses. Structural analysis revealed a conserved epitope near the lateral ridge of EDIII adjoining the EDI–EDIII hinge region. Prophylactic or early therapeutic antibody administration was effective at low doses in mice that were lethally infected with TBEV.  相似文献   
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IntroductionTemporomandibular joint (TMJ) ankylosis is an extremely disabling condition with almost complete inability to open the jaws causing difficulty in chewing, speech, poor oral hygiene and cosmetic disfigurement. Temporalis myofascial flap still remains the most common interpositional material used; however, patients usually complain of pain during movement, unesthetic bulging in the temporal region and trismus due to scar contracture. The main aim of the study was to evaluate the efficacy of abdominal dermis-fat graft and compare it with temporalis myofascial flap as to see which of the two grafts offers more advantages and provides better postoperative results following TMJ ankylosis surgery. Materials and MethodsA total of 30 diagnosed cases of TMJ ankylosis were randomly divided into two groups of 15 patients each. All the patients underwent TMJ ankylosis release under general anesthesia followed by abdominal dermis-fat interposition in Group A and temporalis muscle in Group B. The patients were assessed for pre-operative and postoperative mouth opening (immediate and 6 month postoperative), pain during physiotherapy, donor and surgical site complications and recurrence of ankylosis.ResultsThe mean maximum inter-incisal opening in dermis-fat group was significantly higher than temporalis group both at immediate and 6 month postoperative periods (p = 0.041, 0.001). Physiotherapy was less painful in dermis-fat group than in temporalis group, and the differences in VAS scores among the 2 groups showed high statistical significance (p < 0.001). Hypertrophic scar developed at the donor site in 2 patients in dermis-fat group; however, it was located below the beltline and hardly noticeable. A total of 9 patients (4 in Group A and 5 in Group B) developed temporary facial nerve weakness, and no case of re-ankylosis was noted in either group.ConclusionDermis-fat graft in temporomandibular joint ankylosis showed better results than conventional temporalis myofascial flap in terms of postoperative mouth opening, physiotherapy and jaw function with esthetically acceptable results.  相似文献   
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Patients with long-standing type 1 diabetes (T1D) may exhibit defective glucose counterregulation and impaired hypoglycemia symptom recognition that substantially increase their risk for experiencing severe hypoglycemia. The purpose of this study was to determine whether intrahepatic islet transplantation improves endogenous glucose production (EGP) in response to hypoglycemia in T1D patients experiencing severe hypoglycemia. We studied longitudinally subjects (n = 12) with ∼30 years, disease duration before and 6 months after intrahepatic islet transplantation using stepped hyperinsulinemic-hypoglycemic and paired hyperinsulinemic-euglycemic clamps with infusion of 6,6-2H2-glucose and compared the results with those from a nondiabetic control group (n = 8). After islet transplantation, HbA1c was normalized, and time spent while hypoglycemic (<70 mg/dL) was nearly abolished as indicated by continuous glucose monitoring. In response to insulin-induced hypoglycemia, C-peptide (absent before transplant) was appropriately suppressed, glucagon secretion was recovered, and epinephrine secretion was improved after transplantation. Corresponding to these hormonal changes, the EGP response to insulin-induced hypoglycemia, which was previously absent, was normalized after transplantation, with a similar effect seen for autonomic symptoms. Because the ability to increase EGP is ultimately required to circumvent the development of hypoglycemia, these results provide evidence that intrahepatic islet transplantation can restore glucose counterregulation in long-standing T1D and support its consideration as treatment for patients with hypoglycemia unawareness experiencing severe hypoglycemia.  相似文献   
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A proportion of the operations performed in a surgical gastroenterology department are unplanned repeat laparotomies for complications of the original procedure. We examined why, in our department, these ‘redo’ laparotomies were performed and what was their outcome. We retrospectively analyzed 6530 patients operated between September 1996 - December 2010, of these 257 redo laparotomies were performed in 193(2.5 %) patients. There were 138 males and 55 females who had a mean age of 42 years (range 7–68 years). Eighty one (42 %) of the index surgeries were elective and 112 (58 %) performed in the emergency situation. Pancreas was the commonest organ for the index operation {50 (25.9 %)}, followed by the colon and rectum {45 (23.3 %)} and the small bowel {36 (18.7 %)}. Postoperative bleeding was the most common cause for re-exploration 66 (34.2 %) followed by an abscess or fluid collection that required surgical drainage 57 (29.6 %). The mortality rate after redo laparotomies was 33.2 % with sepsis and multi-organ failure being the commonest cause of death. Urgent redo-laparotomies that are performed following complicated abdominal operations have a high mortality rate. Postoperative bleeding, intrabdominal abscess and peritonitis are the commonest cause for redo-laparotomy. Multiple redolaparotomies and associated co-morbid conditions are significant predictors of mortality.  相似文献   
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The results of bile salt treatment in patients with radiolucent stones and a functioning gall bladder have been poor. In 42 of these patients awaiting cholecystectomy we determined the value of duodenal bile examination in predicting gall stone composition, and thus identifying those less likely to respond to bile salt therapy. Based on chemical analysis and scanning electron microscopy, 28 of 42 (67%) gall stones retrieved at surgery were potentially insoluble. Microscopic examination of duodenal bile correctly identified 21 (75%) of them: it predicted all four (100%) pigment stones, three of six (50%) calcium carbonate containing cholesterol stones, and 14 of 18 (78%) cholesterol stones with pigment shells. It was nearly as reliable as microscopic examination of bile aspirated directly from the gall bladder during surgery (21 (75%) v 23 (82%); p = NS). Furthermore, the presence of cholesterol crystals in duodenal bile was a more sensitive indicator than chemical detection of supersaturation (34 of 38 (89%) v 25 of 35 (71%); p < 0.05) for prediction of cholesterol gall stones. Microscopic examination of duodenal bile, if used as a screening test, could help to exclude potential non-responders and thereby improve considerably the results of oral bile salt treatment for gall stone dissolution.  相似文献   
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