Human BAC-mediated rescue of the Friedreich ataxia knockout mutation in transgenic mice.

Three independent transgenic mouse lines were generated with the human Friedreich ataxia gene, FRDA, in an 188-kb bacterial artificial chromosome (BAC) genomic sequence. Three copies of the transgene per diploid mouse genome were integrated in a single site in each mouse line. Transgenic mice were mated with mice heterozygous for a knockout mutation of the murine Frda gene, to generate mice homozygous for the Frda knockout mutation and hemizygous or homozygous for the human transgene.

Draw the line/respect the line: a randomized trial of a middle school intervention to reduce sexual risk behaviors.

Objectives: This study evaluated the long-term effectiveness of Draw the Line/Respect the Line, a theoretically based curriculum designed to reduce sexual risk behaviors among middle school adolescents.

Methods: The randomized controlled trial involved 19 schools in northern California. A cohort of 2829 sixth graders was tracked for 36 months.

Effects of sildenafil analogue UK 343-664 on a porcine model of acute pulmonary hypertension.

Background: Sildenafil (Pfizer Pharmaceuticals, Sandwich, Kent, UK) has been associated with pulmonary vasorelaxation. A more potent Sildenafil analogue (UK 343-664 [Pfizer Pharmaceuticals]) has been developed, but its effects in vivo have not been studied. This study evaluated the effects of UK 343-664 (Pfizer) during acute pulmonary hypertension.

Nonaqueous capillary zone electrophoresis of synthetic organic polypeptides.

Poly(Nepsilon-trifluoroacetyl-L-lysine) was used as a model solute to investigate the potential of nonaqueous capillary electrophoresis (NACE) for the characterization of synthetic organic polymers. The information obtained by NACE was compared to that derived from size exclusion chromatography (SEC) experiments, and the two techniques were found to be complimentary for polymer characterization. On one hand, NACE permitted (i) the separation of oligomers according to their molar mass and (ii) the separation of the polymers according to the nature of the end groups.

De novo mutations in the mitochondrial ND3 gene as a cause of infantile mitochondrial encephalopathy and complex I deficiency.

Both nuclear and mitochondrial DNA mutations can cause energy generation disorders. Respiratory chain complex I deficiency is the most common energy generation disorder and a frequent cause of infantile mitochondrial encephalopathies such as Leigh's disease and lethal infantile mitochondrial disease. Most such cases have been assumed to be caused by nuclear gene defects, but recently an increasing number have been shown to be caused by mutations in the mitochondrially encoded complex I subunit genes ND4, ND5, and ND6.

Low mutant load of mitochondrial DNA G13513A mutation can cause Leigh's disease.

Respiratory chain complex I deficiency is a common cause of Leigh's disease (LD) and can be caused by mutations in genes encoded by either nuclear or mitochondrial DNA (mtDNA). Most pathogenic mtDNA mutations act recessively and only cause disease when present at high mutant loads (typically >90%) in tissues such as muscle and brain. Two mitochondrial DNA mutations in complex I subunit genes, G14459A in ND6, and T12706C in ND5, have been associated with complex I deficiency and LD.

Vero cytotoxin-producing Escherichia coli O157 gastroenteritis in farm visitors, North Wales.

An outbreak of Vero cytotoxin-producing Escherichia coli O157 (VTEC O157) gastroenteritis in visitors to an open farm in North Wales resulted in 17 primary and 7 secondary cases of illness. E. coli O157 Vero cytotoxin type 2, phage type 2 was isolated from 23 human cases and environmental animal fecal samples.

Evaluation of safety balls and faceguards for prevention of injuries in youth baseball.

Context: Safety balls and faceguards are widely used in youth baseball, but their effectiveness in reducing injury is unknown.

Objective: To evaluate the association of the use of faceguards and safety balls and injuries in youth baseball.

Design, Setting, And Participants: Ecological study using a national database of compensated insurance claims maintained by Little League Baseball Incorporated, combined with data on the number of participants in Little League and data from a census of protective equipment usage for youth aged 5 to 18 years participating in Little League Baseball in the United States during 1997-1999.

Effective approaches to reducing adolescent unprotected sex, pregnancy, and childbearing.

In the United States, there exist a multitude of different approaches to reducing adolescent sexual risk-taking, unintended pregnancy, childbearing, and sexually transmitted disease, including HIV. While many of these approaches have some positive effects upon some outcomes (such as greater knowledge), only some of these programs actually delay the initiation of sex, increase condom or contraceptive use, and reduce unprotected sex among youth. This article summarizes a review of 73 studies and their respective programs, and describes four groups of programs which have reasonably strong evidence that they delay sex, increase condom or contraceptive use, or reduce teen pregnancy or childbearing.

The impact of schools and school programs upon adolescent sexual behavior.

Because most youth are enrolled in school for many years before they initiate sex and when they initiate sex, schools have the potential for reducing adolescent sexual risk-taking. This paper reviews studies which examine the impact upon sexual risk-taking of school involvement, school characteristics, specific programs in school that do not address sexual behavior, and specific programs that do address sexual risk-taking. Multiple studies support several conclusions.

Antecedents of adolescent initiation of sex, contraceptive use, and pregnancy.

Objective: To identify the most important antecedents associated with adolescent initiation of sex, contraceptive use, and pregnancy.

Methods: Statistically significant antecedents in more than 250 studies were identified and summarized.

Results: More than 100 antecedents create a complex and detailed picture of the correlates of adolescent sexual behaviors.

Potent and long-acting corticotropin releasing factor (CRF) receptor 2 selective peptide competitive antagonists.

We present evidence that members of the corticotropin releasing factor (CRF) family assume distinct structures when interacting with the CRF(1) and CRF(2) receptors. Predictive methods, physicochemical measurements, and structure-activity relationship studies have suggested that CRF, its family members, and competitive antagonists such as astressin [cyclo(30-33)[DPhe(12),Nle(21),Glu(30),Lys(33),Nle(38)]hCRF((12-41))] assume an alpha-helical conformation when interacting with their receptors. We had shown that alpha-helical CRF((9-41)) and sauvagine showed some selectivity for CRF receptors other than that responsible for ACTH secretion(1) and later for CRF2.

Nutrition and sports supplements: fact or fiction.

Background: In an age of highly competitive sports, whether it be the high school student, the weekend warrior, or the professional athlete, more individuals are using "performance-enhancing" nutritional supplements. Many feel they are gaining a "competitive edge," without thinking of the potential consequences. Consumers are inundated with claims of strength, weight loss, and improved body definition, but they are rarely given information on the potentially harmful side effects.

Lack of benefit of an active pectoral pulse generator on atrial defibrillation thresholds.

Introduction: Atrial defibrillation can be achieved with standard implantable cardioverter defibrillator leads, which has led to the development of combined atrial and ventricular devices. For ventricular defibrillation, use of an active pectoral electrode (active can) in the shocking pathway markedly reduces defibrillation thresholds (DFTs). However, the effect of an active pectoral can on atrial defibrillation is unknown.

Hyponatraemia in elderly psychiatric patients treated with Selective Serotonin Reuptake Inhibitors and venlafaxine: a retrospective controlled study in an inpatient unit.

Objective: To determine the prevalence of hyponatraemia associated with selective serotonin reuptake inhibitor (SSRI) and venlafaxine use in elderly patients compared to that in elderly patients not prescribed these drugs, while controlling for age, sex, depression status and illnesses or prescribed medications also associated with hyponatraemia. Design and setting Retrospective controlled analysis in a 36-bed inpatient unit for elderly psychiatric patients in Melbourne.

Patients: Inpatients (199) with a mean age of 74.

Safer choices: reducing teen pregnancy, HIV, and STDs.

Objectives: This study evaluated the long-term effectiveness of Safer Choices, a theory-based, multi-component educational program designed to reduce sexual risk behaviors and increase protective behaviors in preventing HIV, other STDs, and pregnancy among high school students.

Methods: The study used a randomized controlled trial involving 20 high schools in California and Texas. A cohort of 3869 ninth-grade students was tracked for 31 months from fall semester 1993 (baseline) to spring semester 1996 (31-month follow-up).

Accidental sharp force injury fatalities.

The authors review all accidental sharp force injury deaths investigated at the Southwestern Institute of Forensic Sciences from 1990 to 1999. Twenty-two cases of accidental sharp force injury were identified, accounting for 0.29% of all accidental deaths (9,562) during the 10-year study period.

A brief overview of the development of aerospace medicine in the United States.

Aerospace medicine has evolved into a legitimate specialty through a long process of historical observation and technical achievement. However, most public literature on the topic has only covered information written through the late 1960s. This paper seeks to give a brief overview of the development of aerospace medicine and includes information about early advances in the field as well as more recent data.

Decisions for enteral access in the intensive care unit.

When making decisions regarding nutrition support, many factors must be considered before committing a patient to receive parenteral or enteral nutrition. Parenteral nutrition (PN) is more expensive and technically more difficult to administer than enteral nutrition (EN). The charge for PN can range from US 200 dollars to 1000 dollars per day, where a standard hospital diet or enteral tube feedings might cost less than US 25 dollars/d.

Identification of potent and selective neuropeptide Y Y(1) receptor agonists with orexigenic activity in vivo.

Neuropeptide Y (NPY) binds to a family of G-protein coupled receptors termed Y(1), Y(2), Y(3), Y(4), Y(5), and y(6). The use of various receptor subtype-selective agonists and antagonists has facilitated identification of the receptor subtypes responsible for mediating many of the biological effects of NPY. For example, the potent orexigenic activity of NPY is believed to be mediated by both the Y(1) and Y(5) receptor subtypes.

Injuries in little league baseball from 1987 through 1996: implications for prevention.

Unlabelled: Baseball is a very popular team sport in the United States, but there has been concern with the number of injuries and fatalities.

Objective: This study describes the incidence of injuries to Little League Baseball, Inc, players from 5 to 12 years old from 1987 through 1996.

Methods: Descriptive statistical analyses of injuries derived from Little League Baseball, Inc, insurance data from 17,221,210 player-years of follow-up in the 10-year study period.