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Spontaneous Loss (spontaneous + loss)
Selected AbstractsSpontaneous HBeAg seroconversion and loss of hepatitis B virus DNA after acute flare due to development of drug resistant mutants during entecavir monotherapyHEPATOLOGY RESEARCH, Issue 1 2009Ri-Cheng Mao Aims:, Patients with chronic hepatitis B virus (HBV) infection under entecavir (ETV) treatment develop resistant mutants with viral rebound. Here, we report an interesting case of spontaneous loss of HBV-DNA and seroconversion following an acute flare after the development of ETV-resistant mutants. This patient received ETV after lamivudine breakthrough. Methods:, Cloning and sequence analysis of the HBV reverse transcriptase (RT) region were performed with seven samples during ETV therapy. In addition, two full-length HBV genomes derived from samples before and after the emergence of ETV resistance were sequenced. Results:, ETV resistant mutants appeared at week 228, with virological and biochemical rebound at the same time. Unexpectedly, HBeAg seroconversion occurred 8 weeks later. The viral load decreased and became undetectable from week 252. Analysis of HBV isolates in the patient at week 124 revealed that wild-type HBV was predominant at that time and ETV resistant mutants were not found among 20 clones. Interestingly, a new mutant type with rtL180M+rtT184L was found alongside rtL180M+rtT184L+rtM204V/I at week 228 and appeared to develop independently, according to the sequence analysis. In contrast to the previously identified ETV resistant mutants, it did not carry the rtM204V/I mutations. Conclusion:, The data presented here indicates that the flare following the emergence of ETV resistant mutants may reflect immune-mediated control of HBV infection, leading to a spontaneous loss of HBV-DNA and seroconversion. [source] Intrinsic stability and functional properties of disulfide bond-stabilized coagulation factor VIIIa variantsJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 6 2006A. J. GALE Summary.,Background:,The utility of purified coagulation factor (F)VIII for treatment of hemophilia A is limited in part by its instability following activation by thrombin, which is caused by spontaneous dissociation of the A2 domain from the activated FVIII (FVIIIa) heterotrimer. To prevent this A2 domain dissociation in FVIIIa, we previously engineered a cysteine pair (C664,C1826) in recombinant FVIII that formed a disulfide bond cross-linking the A2 domain in the heavy chain to the A3 domain in the light chain. This engineered disulfide bond resulted in a more stable FVIIIa. Aims:,Here, we characterize the functional parameters of C664,C1828 FVIII and of a new disulfide bond-stabilized FVIII (C662,C1828 FVIII). Methods:,In order to assess whether these FVIII variants might be good candidates for a new therapeutic agent to treat hemophilia A, we investigated a variety of functional parameters that might affect the in vivo properties of the variants, including half-life of disulfide bond-stabilized FVIII and FVIIIa and the potency of these FVIIIa molecules in the FXase complex. Results:,Both disulfide bond-stabilized variants had improved affinity for von Willebrand factor (VWF). In studies of FX activation by purified FIXa and FVIIIa, C662,C1828 FVIIIa had normal activity while C664,C1826 FVIIIa had reduced activity. Both C664,C1826 FVIIIa and C662,C1828 FVIIIa were inactivated by activated protein C (APC) but the rates of inactivation were different. Conclusion:,Overall, the specific location of the disulfide bridge between the A2 and A3 domains appears to affect functional properties of FVIIIa. In summary, introduction of engineered interdomain disulfides results in FVIIIa variants that resist spontaneous loss of activity while retaining susceptibility to APC proteolytic inactivation and maintaining VWF binding. [source] Herpes zoster in HIV infection with osteonecrosis of the jaw and tooth exfoliationORAL DISEASES, Issue 5 2006P Siwamogstham Background:, Herpes zoster (HZ) infection of the trigeminal nerve is associated with complications such as postherpetic neuralgia, facial scarring, loss of hearing ability and conjunctivitis. Until 2005, postherpetic alveolar necrosis and spontaneous tooth exfoliation have been described in 20 cases unrelated to HIV infection. Objective:, The aim of this study was to describe HIV infection in patients (two women, two men, average age 30 years) who suffered from HZ attacks to their trigeminal nerves. Main outcome measures:, None of the patients had received antiherpetic medications or antiretroviral therapy. HIV infection was only diagnosed after the development of HZ. Facial scarring with depigmentation and hyperesthesia (postherpetic neuralgia) was diagnosed in all four patients. Oral findings consisted of spontaneous loss of both maxillary or mandibular teeth. Osteonecrosis of varying extent was also found. Treatment consisted of extractions of teeth and administration of antibiotics and analgesics. Healing of alveolar wounds was unremarkable. Conclusion:, Complications affecting the alveolar bone and teeth seem to be rare in HIV-infected patients. [source] Translocation of a cerclage band into the endocervical canal after preconception transabdominal cervico-isthmic cerclageJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 1 2010Moon-Il Park Abstract A 34-year-old woman, who had a history of five spontaneous losses and failures of two McDonald purse-string cerclages, underwent a transabdominal cervico-isthmic cerclage (TCC). She became pregnant 17 months after TCC. At 35 weeks of gestation, she was admitted to our hospital due to preterm labor and delivered a healthy female baby (2270 g) by cesarean section. After delivery of the newborn infant, we found a migration of about one third of the cerclage band into the endocervical canal. Two years later, she had one further pregnancy, reached 33 weeks of gestation, and delivered a 1450 g male baby by cesarean section due to a preterm labor without any signs of infection. Although it could have been a case of pure coincidence, we take a chance to speculate that the migration of the cerclage band into the endocervical canal might have been the reason for the preterm labor, and it must have been removed at her first cesarean section and replaced by a new cerclage band for her next pregnancy. [source] Antinuclear Autoantibodies, Complement Level, Hypergammaglobulinemia and Spontaneous Intrauterine Hematoma in Pregnant WomenAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 1 2003Jaume Alijotas Problem: To examine the associative relationship among autoantibodies, C4 levels and intrauterine hematomas (IUH) in more detail than in the studies published earlier. Method Of Study: We performed a retrospective study of 54 women with poor obstetric outcomes. Sera were screened for antinuclear antibodies (ANA), anti-DNA antibodies, antiphospholipid antibodies (aPL), and antithyroid antibodies. C4-complement and gammaglobulin levels were also monitored. We compared the main variables in IUH complicated pregnancy group with the risk pregnancy group without IUH. We also compared these variables in the IUH cases before and during IUH. Results: Eight IUH were detected. The average number of spontaneous losses for these eight women was 3.3 ± 2.1 (range: 1,8). aPL was present in 100% of cases. ANAs and hypergammaglobulinemia were present in 50% of cases and low C4 in 87.5% of cases. After comparing these variables apart from C4 before and during IUH, we found no statistical differences. However, C4 was low in four patients before IUH and in seven patients during IUH (OR: 7.0; 95% CI: 0.57,86.33). When we compared autoantibodies apart from lupus anticoagulant (LAC) between the two groups, no differences were observed. However, seven of the eight (87.5%) patients with IUH were LAC positive whereas only 24 of the 46 patients (52.1%) were positive in the non-IUH group (OR: 6.42; 95% CI: 0.73,56.41). Rapid plasma reagin was present in 8/46 in the non-IUH group (16.7%) and 5/8 in the IUH group (62.5%) P < 0.015). Conclusions: In women with poor obstetric histories, autoantibodies, especially antiphospholid antibodies, may play a role in the IUH development especially if low C4 and/or hypergammaglobulinemia are present. [source] | ||||||||||