Polymerase chain reaction detection of cytomegalovirus and human immunodeficiency virus-1 in the retina of patients with acquired immune deficiency syndrome with and without cotton-wool spots.

Purpose: The authors determine the association, if any, between detection of human cytomegalovirus (CMV) and human immunodeficiency virus (HIV) nucleic acids and retinal lesions in patients with acquired immune deficiency syndrome.

Methods: Postmortem eyes were examined with a dissecting microscope and light microscopy. Retinal cotton-wool spots (CWS) were removed using a clean touch punch biopsy technique.

Baseline characteristics, natural history, and risk factors to progression in eyes with stage 2 macular holes. Results from a prospective randomized clinical trial. Vitrectomy for Macular Hole Study Group.

Purpose: The purpose of this study is (1) to determine baseline characteristics and natural history of immature full-thickness macular holes, (2) to describe progression and resolution, and (3) to present new aspects of pathogenesis of idiopathic macular hole.

Methods: The authors analyzed 41 eyes with stage 2 macular holes (37 patients) in a multicentered prospective randomized trial; 19 eyes were randomized to observation (versus surgery) and had more than 12 months of follow-up, allowing determination of the natural course. Baseline and subsequent examinations included best-refracted visual acuity (Early Treatment of Diabetic Retinopathy Study, potential acuity meter, Pelli-Robson contrast sensitivity, and Bailey-Lovie reading vision), of clinical examinations, photography, and fluorescein angiography.

From population to genome: ecogenetics of Leishmania (Viannia) braziliensis and L. (V.) peruviana.

The size polymorphism of nine chromosomes, recognized by specific probes, was analysed in populations of Leishmania (Viannia) braziliensis and L. (V.) peruviana from various Peruvian biogeographical units.

Prevention of hepatitis B virus transmission by immunization. An economic analysis of current recommendations.

Objective: To evaluate the outcome of immunization strategies to prevent hepatitis B virus (HBV) transmission.

Design And Setting: A decision model was used to determine the incremental effects of the following hepatitis B immunization strategies in a birth cohort receiving immunization services in the public sector: (1) prevention of perinatal HBV infection, (2) routine infant vaccination, or (3) routine adolescent vaccination.

Main Outcome Measures: Over the lifetime of the cohort, the reduction in infections and medical and work-loss costs of HBV-related liver disease were determined for each strategy and compared with the outcome without immunization.

Intravitreous and plasma concentrations of ganciclovir and foscarnet after intravenous therapy in patients with AIDS and cytomegalovirus retinitis.

This study evaluated intravitreous and plasma ganciclovir and foscarnet concentrations after intravenous administration in AIDS patients with cytomegalovirus (CMV) retinitis and retinal detachment. Undiluted vitreous samples were prospectively obtained from 60 eyes (52 patients) at the time of pars plana vitrectomy. Thirty-three plasma samples (from 27 patients in the initial group of 52) were obtained simultaneously during surgery on 33 eyes.

Plasticity of gp63 gene organization in Leishmania (Viannia) braziliensis and Leishmania (Viannia) peruviana.

The genomic organization of gp63 genes in 4 and 7 isolates of Leishmania braziliensis and L. peruviana, respectively was studied by RFLP analysis with 3 restriction enzymes (Bgl I, Sal I and Apa I). Our results showed a marked polymorphism among isolates.

Putative Leishmania hybrids in the Eastern Andean valley of Huanuco, Peru.

During an outbreak of tegumentary leishmaniasis that developed in the 1990s in the Eastern Andean valley of Huanuco, Peru, the coexistence of Andean (uta) and sylvatic leishmaniases was suspected for ecological and geographical reasons, and sympatric sampling was carried out. Seven human isolates of Leishmania were characterized by multilocus enzyme electrophoresis, random amplification of polymorphic DNA and molecular karyotyping. The three methods identified 3 isolates as L.

Extensive polymorphism at the Gp63 locus in field isolates of Leishmania peruviana.

Genetic diversity within and between tandemly arrayed copies of the Gp63 gene occurs in laboratory isolates of Leishmania spp., but the extent to which this represents natural genetic diversity has not been assessed. Here, the Gp63 locus is examined in 58 fresh isolates of L.

Glycerophosphorylcholine, a component of both Ascaris suum muscle and Caenorhabditis elegans.

Studies of the muscle phospholipid metabolism of Ascaris suum suggest an effect of cholinergic drugs on the turnover of phosphatidylcholine and the generation of glycerophosphorylcholine (GPC). 31P-nuclear magnetic resonance (NMR) studies of helminths revealed the presence of a major peak that was assigned to GPC. The primary effect of the cholinergic drugs on the parasites' phosphate profile appeared to be on the level of GPC.

Towards structure-based drug design: crystal structure of a multisubstrate adduct complex of glycinamide ribonucleotide transformylase at 1.96 A resolution.

An inhibitor complex structure of glycinamide ribonucleotide transformylase (GAR-Tfase; EC 2.1.2.

Intravitreal cidofovir (HPMPC) treatment of cytomegalovirus retinitis in patients with acquired immune deficiency syndrome.

Purpose: The authors previously conducted a pilot, dose-escalating study which suggested that a 20-micrograms dose of intravitreal cidofovir (HPMPC) may be safe and effective in treating cytomegalovirus (CMV) retinitis in humans. The purpose of this series is to expand the authors' prior experience with the 20-micrograms dose of cidofovir as the sole treatment for CMV retinitis in patients with acquired immune deficiency syndrome.

Methods: The study design was an unmasked consecutive case series trial in a single-center institutional retina referral practice.

Phase I/II study of intravitreal cidofovir for the treatment of cytomegalovirus retinitis in patients with the acquired immunodeficiency syndrome.

Purpose: In this study we evaluated the safety and efficacy of the nucleoside phosphonate analogue intravitreal cidofovir to treat cytomegalovirus retinitis in humans.

Methods: We conducted a phase I/II unmasked consecutive case series in a single-center institutional referral practice. Eligible patients with the acquired immunodeficiency syndrome had active cytomegalovirus retinitis in at least one eye, despite adequate intravenous therapy with ganciclovir or foscarnet, were intolerant to intravenous therapy, were noncompliant with intravenous therapy, or refused intravenous therapy.

Karyotype plasticity in neotropical Leishmania: an index for measuring genomic distance among L. (V.) peruviana and L. (V.) braziliensis populations.

A method for phenetic analysis of karyotype data has been developed for Leishmania populations. Measurement of size difference between chromosomes recognized by a given DNA probe in different isolates led to the formulation of a Chromosome Size Difference Index (CSDI). The method was applied to phenetic analysis of 4 sets of chromosomes--each set being recognized by a different probe--in 37 L.

Structural analysis of antibody specificity. Detailed comparison of five Fab'-steroid complexes.

Structures of the Fab' fragment of the anti-progesterone antibody DB3 in complex with five cross-reactive steroids (aetiocholanolone, 5 beta-androstane-3,17-dione, 5 alpha-pregnane-20-one-3 beta-ol-hemisuccinate, progesterone-11 alpha-ol-hemisuccinate and progesterone) have been determined by X-ray crystallography to a maximum resolution of 2.7 A. These different steroids compete with progesterone binding with affinities in the nanomolar range despite substantial differences in their three-dimensional structures.

Prevalence rate of hypertension among recent Southeast Asian refugees to northern California.

Background: Little is known regarding the prevalence rate of hypertension among recent Southeast Asian refugees to the United States.

Methods: In this randomized, prospective study, four northern California counties with large Southeast Asian refugee populations were screened for the prevalence rates of hypertension and borderline hypertension. A population density method based upon 1988 census data was used to screen a representative sample of subjects from each county.

Natural Leishmania infection of Lutzomyia spp. in Peru.

Natural infection of Lutzomyia spp. with Leishmania was studied with the aid of the polymerase chain reaction (PCR) in Chaute, Lima, Perú, a locality endemic for Andean cutaneous leishmaniasis (uta). The PCR, with primers specific for the L.

Trends in maternity care by graduates and the effect of an intervention.

Background And Objectives: Only 24% of family physicians in the United States deliver babies, a figure that declined remarkably during the decade of the 1980s. This study examines the content of practice, with regard to maternity care, of graduates of the University of California, Davis Family Practice Residency Network over the past 20 years, and the effectiveness of residency training intervention designed to increase maternity care activity among graduates.

Methods: Using a mailed survey instrument, graduates of the UC Davis Family Practice Residency Network have been periodically surveyed on practice characteristics since 1978.

Monoclonal antibodies against progesterone: effect of steroid-carrier coupling position on antibody specificity.

Monoclonal anti-progesterone antibodies were raised by immunizing mice with progesterone coupled through either the C3, C6 or C11 positions to protein carrier (bovine serum albumin, BSA). The specificity of four antibodies for a range of steroids related to progesterone, some carrying substitutions at various ring positions, was studied by competitive inhibition in an ELISA system. The results demonstrated that the ring coupling position has a determining effect on the cross-reactivity of the antibodies obtained.

Molecular basis of crossreactivity and the limits of antibody-antigen complementarity.

Two major unanswered questions concerning the specificity of antibodies are: how do structurally different antigens bind with high affinity to the same antibody, and what are the limits of the antibody combining site complementarity and flexibility that contribute to such crossreactivity? We report here a comparative analysis of the X-ray structures of five conformationally different steroids in complex with the Fab' fragment of an anti-progesterone antibody DB3 at 2.7 A. This antibody is unable to complement completely the shape of the hydrophobic antigen so that crossreactivity occurs with other ligands without major structural rearrangements of the binding site.

Diagnosis of Leishmania using the polymerase chain reaction: a simplified procedure for field work.

Oligonucleotide primers directed to the minicircle kinetoplast DNA of Leishmania strains supported enzymatic amplification of this DNA by the polymerase chain reaction (PCR). A single product of 70 basepairs was obtained from parasites belonging exclusively to the L. braziliensis complex.