Arthropod phylogenetics in light of three novel millipede (myriapoda: diplopoda) mitochondrial genomes with comments on the appropriateness of mitochondrial genome sequence data for inferring deep level relationships.

Background: Arthropods are the most diverse group of eukaryotic organisms, but their phylogenetic relationships are poorly understood. Herein, we describe three mitochondrial genomes representing orders of millipedes for which complete genomes had not been characterized. Newly sequenced genomes are combined with existing data to characterize the protein coding regions of myriapods and to attempt to reconstruct the evolutionary relationships within the Myriapoda and Arthropoda.

Phylogenetics of the millipede genus Brachycybe Wood, 1864 (Diplopoda: Platydesmida: Andrognathidae): patterns of deep evolutionary history and recent speciation.

The genus Brachycybe Wood is a little known group of millipedes comprising eight nominal species distributed throughout North America, Japan, South Korea, Taiwan, and China. The group's species are relatively morphologically homogenous and have been described primarily on the basis of differences in somatic morphology largely ignoring the often-used characters in millipede taxonomy and systematics - male genitalia (the gonopods). The objectives of this study were to survey male gonopods with the aim of evaluating inter-specific variation, assess existing species boundaries and phylogeny using molecular characters, examine the historical biogeography of the genus, and estimate the timing of lineage divergence using a molecular clock.

Age-specific seroprevalence of HIV, hepatitis B virus, and hepatitis C virus infection among injection drug users admitted to drug treatment in 6 US cities.

Objectives: This study measured age-specific seroprevalence of HIV, hepatitis B virus, and hepatitis C virus (HCV) infection among injection drug users (IDUs) admitted to drug treatment programs in 6 US cities.

Methods: Remnant sera collected from persons entering treatment with a history of illicit drug injection were tested for antibodies to HIV, hepatitis C (anti-HCV), and hepatitis B core antigen (anti-HBc).

Results: Prevalence of anti-HBc and anti-HCV increased with age and reached 80% to 100% among older IDUs in all 6 cities.

Radioimmunoassay for monitoring zidovudine in dried blood spot specimens.

We modified and evaluated a RIA for serum and used the modified RIA to measure zidovudine in dried blood spot specimens (DBSs) routinely collected for newborn screening and tested anonymously for maternally acquired HIV antibodies in the national HIV Seroprevalence Survey Among Childbearing Women. DBS calibration and quality-control materials were used to adapt the serum assay to the DBS matrix. The assay had a limit of detection of 24 micrograms/L serum and was used to measure zidovudine from both whole DBSs and the eluate remaining after HIV antibody screening.

Helper T-lymphocyte count. TRAx CD4 test kit versus conventional flow cytometry.

Background: We evaluated a newly developed enzyme-linked immunosorbent assay system for measuring helper T-lymphocyte count.

Methods: Data from 111 human immunodeficiency virus-infected injection drug users in a cohort study were analyzed by flow cytometry and independent duplicate runs of the TRAx enzyme-linked immunosorbent assay.

Results: The mean helper T-cell counts were 470, 480, and 506 per microliter by flow cytometry and TRAx runs 1 and 2, respectively.

Surveillance for human immunodeficiency virus type 1 group O infections in the United States.

Background: Reports that the human immunodeficiency virus type 1 (HIV-1) group O variants are not reliably detected by some commercial diagnostic tests have raised concerns about the sensitivity of existing screening tests, especially with regard to blood safety. Although it is unlikely that these divergent strains are prevalent in North America, systematic, continuous surveillance is needed to monitor the potential spread of HIV variants into that region.

Study Design And Methods: Stored serum samples (n = 1072) from both high- and low-risk population groups at several sites in the United States and Puerto Rico were tested by peptide enzyme immunoassays specific for the prototypic HIV-1 group O strains, MVP5180 and ANT70.

Sentinel surveillance for HIV-2 infection in high-risk US populations.

Objectives: We conducted sentinel surveillance in persons practicing behaviors known to transmit retroviruses to determine the US presence and extent of human immunodeficiency virus type 2 (HIV-2).

Methods: Sentinel surveillance for HIV-2 was conducted by testing 31,533 anonymous blood specimens from patients at sexually transmitted disease clinics, injecting drug users at treatment centers, and clients at HIV counseling and testing sites in 14 US cities where West African immigrants often settle. Specimens were tested by HIV-1 and HIV-2 whole virus and synthetic peptide enzyme immunoassay and confirmed by HIV-1 and HIV-2 Western blots.

Genotypic identification of rickettsiae and estimation of intraspecies sequence divergence for portions of two rickettsial genes.

DNA sequences from specific genes, amplified by the polymerase chain reaction technique, were used as substrata for nonisotopic restriction endonuclease fragment length polymorphism differentiation of rickettsial species and genotypes. The products amplified using a single pair of oligonucleotide primers (derived from a rickettsial citrate synthase gene sequence) and cleaved with restriction endonucleases were used to differentiate almost all recognized species of rickettsiae. A second set of primers was used for differentiation of all recognized species of closely related spotted fever group rickettsiae.

Epidemiology of boutonneuse fever in western Sicily: demonstration of multiple spotted fever group-Rickettsiae subtypes.

Electrophoretic analysis of the proteins and genomic DNA of spotted fever-group Rickettsiae isolated from ticks and a human in Western Sicily show that at least two distinct subtypes other than R. conorii are present in this region. All of the spotted fever-group isolates share common features with other, well-defined spotted fever-group rickettsial species, e.

Addition of monoclonal antibodies specific for Rickettsia akari to the rickettsial diagnostic panel.

Monoclonal antibodies were produced from mice infected with Rickettsia akari (the etiologic agent of rickettsialpox) and evaluated for specificity in indirect fluorescent-antibody tests with 23 different rickettsial antigens. Of the nine antibodies that were evaluated, two were specific for R. akari and four reacted with R.

Flying squirrel-associated Rickettsia prowazekii (epidemic typhus rickettsiae) characterized by a specific DNA fragment produced by restriction endonuclease digestion.

The DNA from flying squirrel-associated Rickettsia prowazekii was characterized by using a specific DNA fragment produced by digestion with the enzyme BamHI. The DNA fragment was cloned into a plasmid vector and used to readily distinguish between available human- and flying squirrel-associated R. prowazekii DNAs derived from crude cytoplasmic extracts.

Ethyl acetate as a substitute for diethyl ether in the formalin-ether sedimentation technique.

Ethyl acetate appears to be a satisfactory subsitute solvent for diethyl ether in the Formalin-ether sedimentation technique. In comparative studies, concentration of organisms with ethyl acetate was equal to or greater than that with diethyl ether. No distortion or alteration of morphology was observed with eigher solvent, and preparations were comparable in appearance and ease of examination.