Functional hepatitis B virus (HBV)-specific T cells are significantly diminished in individuals chronically infected with HBV compared to individuals with self-limiting HBV infection or those on anti-HBV therapy. In individuals infected with human immunodeficiency virus type 1 (HIV-1), coinfection with HBV is associated with an increased risk of worsening liver function following antiviral therapy and of more rapid HBV disease progression. Total HBV-specific T-cell responses in subjects with diverse genetic backgrounds were characterized by using a library of 15-mer peptides overlapping by 11 amino acids and spanning all HBV proteins.
View Article and Find Full Text PDFBackground: Chronic hepatitis B infection (CHB) is a major health problem in Australia and worldwide. CHB is associated with significant long-term morbidity and mortality. Well tolerated treatment is now available, however the development of resistance is common and the optimal timing of treatment is yet to be determined.
View Article and Find Full Text PDFAntimicrob Agents Chemother
September 2004
Entecavir (ETV) exhibits potent antiviral activity in patients chronically infected with wild-type or lamivudine (3TC)-resistant (3TC(r)) hepatitis B virus (HBV). Among the patients treated in phase II ETV clinical trials, two patients for whom previous therapies had failed exhibited virologic breakthrough while on ETV. Isolates from these patients (arbitrarily designated patients A and B) were analyzed genotypically for emergent substitutions in HBV reverse transcriptase (RT) and phenotypically for reduced susceptibility in cultures and in HBV polymerase assays.
View Article and Find Full Text PDFWe report a rapid and accurate real-time PCR-based method to quantify wild-type and lamivudine-resistant hepatitis B virus by using a common forward primer paired with different reverse primers. Excellent concordance was demonstrated between sequencing and the discriminatory real-time assay; however, a mixture of quasispecies was more frequently detected by discriminatory real-time PCR.
View Article and Find Full Text PDFCitrus Sudden Death (CSD), a new, graft-transmissible disease of sweet orange and mandarin trees grafted on Rangpur lime rootstock, was first seen in 1999 in Brazil, where it is present in the southern Triângulo Mineiro and northwestern São Paulo State. The disease is a serious threat to the citrus industry, as 85% of 200 million sweet orange trees in the State of São Paulo are grafted on Rangpur lime. After showing general decline symptoms, affected trees suddenly collapse and die, in a manner similar to trees grafted on sour orange rootstock when affected by tristeza decline caused by infection with Citrus tristeza virus (CTV).
View Article and Find Full Text PDFObjective: To determine the expression and intracellular localization of protein phosphatases 2A (PP2A) and 2B (PP2B), protein kinase A (PKA), and A-kinase anchoring protein (AKAP79), and expression of PKA (RII subunit) binding to AKAP79 in human postmenopausal and pregnant myometrium and to correlate their expressions to blood levels of estradiol, progesterone, and oxytocin.
Methods: Myometrial samples were taken from postmenopausal hysterectomy specimens (group 1, n = 5), from pregnant nonlaboring women (group 2, n = 7) and pregnant laboring women (group 3, n = 5) at cesarean. Western immunoblotting, immunohistochemical, and RII overlay assays were performed.
Background & Aims: Adefovir dipivoxil effectively inhibits both hepatitis B virus (HBV) replication and disease activity in patients with chronic hepatitis B. Resistance to treatment was not observed in 2 recent large placebo-controlled 48-week studies with this drug. The aim of this study was to characterize adefovir resistance in a patient who developed clinical and virologic evidence of breakthrough during a 96-week course of treatment.
View Article and Find Full Text PDFObjective: To determine the prevalence of hepatitis B virus (HBV) genotypic resistance to lamivudine, identify risk factors associated with lamivudine resistance, and characterize the pattern of HBV polymerase mutations in patients co-infected with HIV.
Design: Retrospective cross-sectional study.
Methods: Thirty-three chronic HBV-infected patients were identified from a cohort of 1719 HIV-infected individuals.
Background: Lamivudine (LMV) is the only nucleoside analogue approved for the treatment of chronic hepatitis B (CHB). LMV, as with other nucleoside analogues including Famciclovir (FCV), suppresses the replication of hepatitis B virus (HBV) by targeting the viral polymerase. However, prolonged antiviral therapy results in the emergence of drug resistance HBV which can contribute to virological breakthroughs and recurrent hepatitis flares.
View Article and Find Full Text PDFXylella fastidiosa causes citrus variegated chlorosis (CVC) disease in Brazil and Pierce's disease of grapevines in the United States. Both of these diseases cause significant production problems in the respective industries. The recent establishment of the glassy-winged sharpshooter in California has radically increased the threat posed by Pierce's disease to California viticulture.
View Article and Find Full Text PDFObjective: To determine the infant laceration injury rate during Cesarean sections at Naval Medical Center, San Diego and to describe risk factors associated with this complication.
Methods: Retrospective chart review of all infants born between 1 January 1996 and 31 December, 1999 identified by computer coding as having sustained a birth injury. Fifty randomly selected maternal records of Cesarean sections without infant lacerations were reviewed and analyzed as a control group.
Objective: Hypopituitary GH-deficient patients have an increased cardiovascular mortality and GH replacement in this population has resulted in considerable therapeutic benefit. GH replacement involves administration of a potentially mitogenic substance to patients with a previous or residual pituitary tumour. Our objective was to evaluate whether GH replacement results in an increase in the size of pituitary tumours.
View Article and Find Full Text PDFInt J Gynaecol Obstet
September 2001
Objective: To identify the fetal heart rate patterns that occurred in a 2-h period of time preceding uterine rupture.
Methods: The fetal monitor strips and the medical records of patients with a confirmed diagnosis of uterine rupture were reviewed. These patients delivered at the University of Michigan Hospital from January 1, 1985 to December 31, 1999 and were >or =28 weeks gestational age.
Citrus variegated chlorosis (CVC) and coffee leaf scorch (CLS) are two economically important diseases in Brazil caused by the bacterium Xylella fastidiosa. Strains of the bacterium isolated from the two plant hosts are very closely related, and the two diseases share sharpshooter insect vectors. In order to determine if citrus strains of X.
View Article and Find Full Text PDFObjective: To determine the effectiveness of a voluntary human immunodeficiency virus (HIV) screening program in pregnancy.
Study Design: Using a business decision theory analysis model, we estimated the outcomes and costs of the two possible decisions by our patients (test/no test). Patients with a positive HIV screen would undergo evaluation and possible prophylactic antiviral therapy.
We verified by pathogenicity tests that the herbaceous plant Catharanthus roseus (Madagascar periwinkle) can be used as an experimental host for the strain of Xylella fastidiosa that causes citrus variegated chlorosis (CVC). Plants were mechanically inoculated with CVC strain 9a5c, the genome of which was recently sequenced. Plants were inoculated with the virulent 8th passage (9a5c-8) and the 51st passage (9a5c-51).
View Article and Find Full Text PDFTo study translocation of Xylella fastidiosa to citrus rootstocks, budsticks from citrus variegated chlorosis (CVC)-affected cv. Pera sweet orange (Citrus sinenesis (L.) Osb.
View Article and Find Full Text PDFXylella fastidiosa isolate 8.1.b obtained from a sweet orange tree affected by citrus variegated chlorosis in the state of Sao Paulo, Brazil, and shown in 1993 to be the causal agent of the disease, was cloned by repeated culture in liquid and on solid PW medium, yielding triply cloned strain 9a5c.
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