Online Y-chromosomal short tandem repeat haplotype reference database (YHRD) for U.S. populations.

We describe here an online Y-chromosomal short tandem repeat haplotype reference database (YHRD) for U.S. populations, which represents 9-locus Y-STR haplotypes for 1705 African-Americans, European-Americans and Hispanics as of October 2001.

The influence of a concurrent cognitive task on the compensatory stepping response to a perturbation in balance-impaired and healthy elders.

This study investigated the influence of a concurrent cognitive task on the compensatory stepping response in balance-impaired elders and the attentional demand of the stepping response. Kinetic, kinematic and neuromuscular measures of a forward recovery step were investigated in 15 young adults, 15 healthy elders and 13 balance-impaired elders in a single task (postural recovery only) and dual task (postural recovery and vocal reaction time task) situation. Results revealed that reaction times were longer in all subjects when performed concurrently with a compensatory step, they were longer for a step than an in-place response and longer for balance-impaired older adults compared with young adults.

The interacting effects of cognitive demand and recovery of postural stability in balance-impaired elderly persons.

Background: Although postural recovery is attentionally demanding in healthy elderly persons, an inability to recover balance due to competition for attentional resources between the postural system and a second task could contribute to falls in older adults with poor balance. This study examined the attentional demands of balance recovery from a mild postural disturbance in balance-impaired elderly persons. A second purpose of this research was to determine the effect of performing a cognitive task on the recovery of balance in balance-impaired elderly persons.

A rapid upward step challenges medio-lateral postural stability.

A rapid step up was compared with a rapid step forward to assess the challenge they posed to postural stability in the medio-lateral (ML) direction. The center of pressure (COP) motion, and hip abductor muscle activity were compared between the two tasks in nine young healthy subjects. Analysis revealed that in the step up task there was a greater range and velocity of medio-lateral COP motion, an earlier gluteus medius onset time and a larger magnitude of gluteus medius activity than in the step forward task.

Independent histories of human Y chromosomes from Melanesia and Australia.

To investigate the origins and relationships of Australian and Melanesian populations, 611 males from 18 populations from Australia, Melanesia, and eastern/southeastern Asia were typed for eight single-nucleotide polymorphism (SNP) loci and seven short tandem-repeat loci on the Y chromosome. A unique haplotype, DYS390.1del/RPS4Y711T, was found at a frequency of 53%-69% in Australian populations, whereas the major haplotypes found in Melanesian populations (M4G/M5T/M9G and DYS390.

Melanesian origin of Polynesian Y chromosomes.

Background: Two competing hypotheses for the origins of Polynesians are the 'express-train' model, which supposes a recent and rapid expansion of Polynesian ancestors from Asia/Taiwan via coastal and island Melanesia, and the 'entangled-bank' model, which supposes a long history of cultural and genetic interactions among Southeast Asians, Melanesians and Polynesians. Most genetic data, especially analyses of mitochondrial DNA (mtDNA) variation, support the express-train model, as does linguistic and archaeological evidence. Here, we used Y-chromosome polymorphisms to investigate the origins of Polynesians.

Predicting the probability for falls in community-dwelling older adults using the Timed Up & Go Test.

Background And Purpose: This study examined the sensitivity and specificity of the Timed Up & Go Test (TUG) under single-task versus dual-task conditions for identifying elderly individuals who are prone to falling.

Subjects: Fifteen older adults with no history of falls (mean age=78 years, SD=6, range=65-85) and 15 older adults with a history of 2 or more falls in the previous 6 months (mean age=86.2 years, SD=6, range=76-95) participated.

A prospective study of laboratory and clinical measures of postural stability to predict community-dwelling fallers.

Background: The identification of specific risk factors for falls in community-dwelling elderly persons is required to detect early changes and permit a preventative approach to management. This study determines the ability of various laboratory measures and clinical tests of postural stability to prospectively predict fallers in community-dwelling elderly women.

Methods: One hundred elderly women (65-86 years, mean age 73 +/- 5 years) performed a reaction-time step task, a limits of stability, and a quiet stance balance task.

Characteristics and frequency of germline mutations at microsatellite loci from the human Y chromosome, as revealed by direct observation in father/son pairs.

A number of applications of analysis of human Y-chromosome microsatellite loci to human evolution and forensic science require reliable estimates of the mutation rate and knowledge of the mutational mechanism. We therefore screened a total of 4,999 meioses from father/son pairs with confirmed paternity (probability >/=99. 9%) at 15 Y-chromosomal microsatellite loci and identified 14 mutations.

Ultra fast track in elective congenital cardiac surgery.

Background: Changes in healthcare delivery have affected the practice of congenital cardiac surgery. We recently developed a strategy of limited sternotomy, early extubation, and very early discharge, and reviewed the perioperative course of 198 pediatric patients undergoing elective cardiovascular surgical procedures, to assess the efficacy and safety of this approach.

Methods: One hundred ninety-eight patients aged 0 to 18 years (median 3.

Lateral reach: a clinical measure of medio-lateral postural stability.

Background And Purpose: Medio-lateral postural instability has recently been identified as a risk factor for falls in the elderly community-dwelling population. However, few clinical tests involve challenges to stability limits in the medio-lateral direction. A lateral reach test was thus developed.

Synaptophysin immunoreactivity in primary pigmented nodular adrenocortical disease: neuroendocrine properties of tumors associated with Carney complex.

Carney complex (CNC) is characterized by lentiginosis and myxomatosis together with a variety of endocrine, neural crest-derived, and other tumors, including primary pigmented nodular adrenocortical disease (PPNAD). PPNAD is characterized by lipofuscin-containing, autonomously functioning, cortisol-producing nodules surrounded by mostly atrophic adrenocortical and normal adrenomedullary tissue. The nature and origin of the tumors, including the myxomas and PPNAD, are unclear.

The mercy of adrenocortical tumor cells on lymphocytes.

Immunologic escape includes the loss of Fas-receptor and the gain of Fas-ligand expression. Normal adrenal glands express the Fas-receptor and MHC class II molecules in inner cortical zones. A distinctive feature of adrenocortical tumors is the loss of MHC class II expression.

Effectiveness of a prospective physician self-audit transfusion-monitoring system.

Background: The purpose of this study was to search for a more effective transfusion-monitoring system than the existing system of retrospective peer review.

Study Design And Methods: This research used a study-control, preintervention and postintervention design, to evaluate the effectiveness of a prospective physician self-audit transfusion-monitoring system that functioned without the direct involvement of transfusion service physicians. This research also evaluated the effectiveness of issuing to physicians a memo with transfusion guidelines.

Differential regulation of apoptosis in the normal human adrenal gland.

Analysis of apoptosis in the human adrenal appears to be of eminent importance in the understanding of adrenal structure, zonation, and function. In this study we investigated the programmed cell death of normal adrenal tissues on the basis of apoptotic index by the nonradioactive in situ end labeling of DNA fragments, proliferating cell nuclear antigen, (PCNA), CD95 (cluster of differentiation), major histocompatibility complex class II immunohistochemistry, and ultrastructural analysis. The highest apoptotic index was detected in the outermost zones of the adrenal cortex, mainly in the zona glomerulosa.

Chromium(VI) Forms Thiolate Complexes with gamma-Glutamylcysteine, N-Acetylcysteine, Cysteine, and the Methyl Ester of N-Acetylcysteine.

Reaction of potassium dichromate with gamma-glutamylcysteine, N-acetylcysteine, and cysteine in aqueous solution resulted in the formation of 1:1 complexes of Cr(VI) with the cysteinyl thiolate ligand. The brownish red Cr(VI)-amino acid/peptide complexes exhibited differential stability in aqueous solutions at 4 degrees C and ionic strength = 1.5 M, decreasing in stability in the order: gamma-glutamylcysteine > N-acetylcysteine > cysteine.

Perfect Crystals in the Asymmetric Bragg Geometry as Optical Elements for Coherent X-ray Beams.

Perfect crystals in the asymmetric Bragg geometry are evaluated as optical elements for manipulating coherent X-ray beams. Such optics can be used to modify the transverse coherence length of a synchrotron X-ray beam, with the intention of increasing the usable coherent flux. The wavelength range, angular divergence and flux of X-rays passing through a pinhole aperture are examined in detail, as functions of source and pinhole size, crystal-to-pinhole separation and the asymmetry factor.

Sensitivity and specificity of five different mycoplasma detection assays.

The sensitivity and specificity of five different mycoplasma detection tests were evaluated in comparison with the classical microbiological culture assay on agar plates as the reference method: direct fluorochrome DNA staining (direct DAPI), DNA staining of an indicator cell line (indirect DAPI), RNA hybridization with a cDNA specific for ribosomal mycoplasmal RNA, an enzyme-linked immunosorbent assay (ELISA) with mycoplasma-specific antibodies, and a biochemical cytotoxicity assay (6-MPDR). A large panel of continuous cell lines (20 adherent and 233 suspension cell lines, most of the latter were human leukemia-lymphoma cell lines) were analyzed for infection with mycoplasma. The results of the comparative analysis for sensitivity and specificity of the various tests were as follows: 100% and 100% for the indirect DAPI, 100% and 98% for the RNA hybridization assay, 87% and 94% for the direct DAPI, 72% and 100% for the ELISA, 75% and 90% for the biochemical 6-MPDR assay.

Elimination of mycoplasma from infected leukemia cell lines.

The infection of cell lines with mycoplasma can cause severe problems as the contaminants affect virtually every cell parameter. We attempted to eliminate mycoplasma from contaminated cell lines using the fluoroquinolone antibiotic ciprofloxacin. Mycoplasma-infected cell lines were cultured with 10 micrograms/ml ciprofloxacin for 14 days.

Acid Phosphatase Isoenzyme Profiles in Acute and Chronic Leukemias.

We analyzed the acid phosphatase (AcP) isoenzyme profiles of normal and malignant hematopoietic cells using isoelectric focusing followed by diazo staining. Reproducibly defined bands and band complexes could be identified and were correlated with the cellular material analyzed. Different isoenzyme profiles were indeed associated with the various cell types and cell lineages.