Treadmill aerobic exercise training reduces the energy expenditure and cardiovascular demands of hemiparetic gait in chronic stroke patients. A preliminary report.

Background And Purpose: Elevated energy costs of hemiparetic gait contribute to functional disability after stroke, particularly in physically deconditioned older patients. We investigated the effects of 6 months of treadmill aerobic exercise training on the energy expenditure and cardiovascular demands of submaximal effort ambulation in stroke patients with chronic hemiparetic gait.

Methods: Nine older stroke patients with chronic hemiparetic gait were enrolled in a 6-month program of low-intensity aerobic exercise using a graded treadmill.

Molecular scanning for mutations in the beta 3-adrenergic receptor gene in Nauruans with obesity and noninsulin-dependent diabetes mellitus.

We recently identified a mutation in the human beta 3-adrenergic receptor (beta 3AR) gene (codon 64 TGGTrp -> CGGArg; TRP64ARG) that associates with features of the insulin resistance syndrome and an earlier onset of noninsulin-dependent diabetes mellitus (NIDDM). We scanned the beta 3AR gene for mutations by single stranded conformational polymorphism analysis in 20 Nauruans with obesity and NIDDM. No mutations were identified.

The yellowed archives of yellowcake.

Extensive historical documentation of exposures and releases at government-owned energy facilities is a unique and valuable resource for analyzing and communicating health risks. Facilities at all stages of the atomic fuel cycle were the subject of numerous industrial hygiene, occupational health, and environmental assessments during the Cold War period. Uranium mines and mills on the Colorado Plateau were investigated as early as the 1940s.

Association of cerebral dysgenesis and lactic acidemia with X-linked PDH E1 alpha subunit mutations in females.

We describe an infant girl who presented at age 4 1/2 months with developmental delay, infantile spasms, hypotonia, and elevated lactate levels in the blood and cerebrospinal fluid. She had minor dysmorphic features. Muscle phosphorus magnetic resonance spectroscopy demonstrated reduced phosphocreatine and increased inorganic phosphate, suggesting a defect in oxidative energy metabolism.

A mutation in the beta 3-adrenergic receptor gene is associated with obesity and hyperinsulinemia in Japanese subjects.

The Trp 64 Arg mutation in the beta 3-adrenergic receptor (beta 3AR) gene was investigated in 350 Japanese subjects. This mutation was not associated with non-insulin-dependent diabetes mellitus (NIDDM). In 191 subjects without NIDDM, body mass index (BMI) was significantly higher in subjects homozygous for this mutation than in those homozygous for the normal allele (24.

Lack of IRS-1 codon 513 and 972 polymorphism in Pima Indians.

Insulin receptor substrate-1 (IRS-1), an endogenous substrate for the insulin receptor tyrosine kinase, mediates many or all of the metabolic actions of insulin. Recently, polymorphism at codons 513 and 972 of the IRS-1 gene resulting in 2 amino acid substitutions that were associated with type II diabetes were found in a Caucasian population. Using allele specific oligonucleotide (ASO) hybridization, we screened 242 diabetic and 190 nondiabetic Pima Indians, a population with a very high prevalence of type II diabetes.

Genetic variation in the beta 3-adrenergic receptor and an increased capacity to gain weight in patients with morbid obesity.

Background: The beta 3-adrenergic receptor, located mainly in adipose tissue, is involved in the regulation of lipolysis and thermogenesis. The potential relevance of this receptor to obesity in humans led us to screen obese French patients for a recently identified mutation in the gene for the receptor.

Methods: We used the polymerase chain reaction to amplify a region of the gene for the beta 3-adrenergic receptor encoding amino acid residues 27 to 110 in genomic DNA extracted from leukocytes from 185 patients with morbid obesity (body-mass index [the weight in kilograms divided by the square of the height in meters], > 40) and 94 normal subjects.

Time of onset of non-insulin-dependent diabetes mellitus and genetic variation in the beta 3-adrenergic-receptor gene.

Background: The beta 3-adrenergic receptor is expressed in visceral adipose tissue and is thought to contribute to the regulation of the resting metabolic rate and lipolysis.

Methods: To investigate whether mutations in the gene for the beta 3-adrenergic receptor predispose patients to obesity and non-insulin-dependent diabetes mellitus (NIDDM), we studied this gene in 10 Pima Indians by analysis of single-stranded conformational polymorphisms and dideoxy sequence analysis. Association studies were performed in 642 Pima subjects (390 with NIDDM and 252 without NIDDM).

Geometric changes allow normal ejection fraction despite depressed myocardial shortening in hypertensive left ventricular hypertrophy.

Objectives: This study of hypertensive left ventricular hypertrophy 1) assessed myocardial shortening in both the circumferential and long-axis planes, and 2) investigated the relation between geometry and systolic function.

Background: In hypertensive left ventricular hypertrophy, whole-heart studies have suggested normal systolic function on the basis of ejection fraction-systolic stress relations. By contrast, isolated muscle data show that contractility is depressed.

Imaging of axonal damage in vivo in Rasmussen's syndrome.

We obtained magnetic resonance spectroscopic images (MRSIs) in three patients with Rasmussen's syndrome. The relative resonance intensity of N-acetylaspartate (NAA) to creatine (NAA:Cr), an index of neuronal loss or damage, was determined for various regions within the brain, and the affected:unaffected hemisphere asymmetry ratio was determined. All three patients had decreased relative NAA signal intensity over the entire affected hemisphere.

Pelizaeus-Merzbacher disease in a family of Portuguese origin caused by a point mutation in exon 5 of the proteolipid protein gene.

Single-strand conformational polymorphism analysis of an affected male with Pelizaeus-Merzbacher disease (PMD) showed a slight change in mobility of amplified exon 5 of the proteolipid protein (PLP) gene. The exon was sequenced and a G-->A transition at codon 216 was found. This mutation eliminates a BstNI restriction site and creates a MaeI restriction site.

Impact of chamber geometry and gender on left ventricular systolic function in patients > 60 years of age with aortic stenosis.

In aortic stenosis, gender and other differences in the adaptive remodeling of the left ventricle have been described, but the influence of left ventricular (LV) geometry on systolic function is not widely appreciated. This study tested the hypothesis that the increased ejection fraction seen in some elderly women with aortic stenosis is due to changes in LV geometry, not increased myocardial mass or enhanced myocardial function. We therefore investigated gender-related differences in LV and myocardial function by analysis of end-systolic circumferential stress versus shortening relations in 65 patients (29 men and 36 women) with aortic stenosis who underwent cardiac catheterization and echocardiography.

Benign familial nocturnal alternating hemiplegia of childhood.

In infancy, two brothers developed recurrent attacks of alternating or bilateral hemiplegia arising exclusively out of sleep. The episodes were terminated by even brief sleep. Neither child had hypotonia, dystonic attacks, paroxysmal eye movement abnormalities, or other features characteristic of the now-classic form of alternating hemiplegia of childhood (AHC).

Blood flow velocity in the right coronary artery: assessment before and after angioplasty.

Objectives: This study attempted 1) to assess the utility of rest measurements of intracoronary blood flow velocity for the physiologic assessment of coronary stenoses before and after right coronary artery angioplasty, and 2) to compare the phasic flow pattern in the right coronary artery proper with the phasic flow pattern in its major branches to the left ventricle.

Background: Previous investigations have demonstrated that a reduction in distal blood flow velocity and a loss of distal diastolic predominant flow are characteristic of physiologically significant stenoses and that these indexes normalize after successful coronary artery dilation. However, these studies were predominantly performed in the left coronary artery.

Human interindividual variability--a major source of uncertainty in assessing risks for noncancer health effects.

For noncancer effects, the degree of human interindividual variability plays a central role in determining the risk that can be expected at low exposures. This discussion reviews available data on observations of interindividual variability in (a) breathing rates, based on observations in British coal miners; (b) systemic pharmacokinetic parameters, based on studies of a number of drugs; (c) susceptibility to neurological effects from fetal exposure to methyl mercury, based on observations of the incidence of effects in relation to hair mercury levels; and (d) chronic lung function changes in relation to long-term exposure to cigarette smoke. The quantitative ranges of predictions that follow from uncertainties in estimates of interindividual variability in susceptibility are illustrated.

Medical treatment of Rasmussen's syndrome (chronic encephalitis and epilepsy): effect of high-dose steroids or immunoglobulins in 19 patients.

We treated 19 patients with Rasmussen's syndrome (chronic encephalitis and epilepsy)--a rare progressive disorder of unknown etiology causing focal epilepsy, hemiparesis, and intellectual deterioration--with intravenous immunoglobulins, high-dose steroids, or both, to control seizures and improve the end point of the disease. Ten of 17 patients receiving steroids, and eight of nine patients receiving immunoglobulins, had some reduction of seizure frequency in the short term. Improvement in hemiparesis was slight.

Fulminant hepatic failure associated with status epilepticus in children: three cases and a review of potential mechanisms.

Fulminant hepatic failure is a rare complication of status epilepticus. Although many of the anticonvulsants used to treat the seizures are known to have hepatotoxic properties, the exact mechanism leading to massive destruction of the liver following a prolonged seizure remains unclear. Three children are presented who developed fulminant hepatic failure following status epilepticus and subsequently died of multiple organ failure.

Rehabilitation medicine.

This article presents a limited overview of the assistance rehabilitation medicine can offer the elderly surgical patient. Appropriately timed rehabilitation can positively affect surgical outcome of elderly patients by restoring physical abilities and promoting independent function. Specific techniques and programs that follow rehabilitation principles can help offset organ system impairment associated with the aging process itself.

The use of scintigraphy in the management of patients with pulmonary aspiration.

Pulmonary aspiration was assessed using a scintigraphic swallowing procedure in 14 dysphagics in whom penetration of the larynx had been previously diagnosed. No patient had recent evidence of aspiration pneumonia. Imaging was performed during and following ingestion of a cupful of thin liquid admixed with between 1-2 mCi of Tc-99m sulfur colloid.

Proton MR spectroscopic characterization of differences in regional brain metabolic abnormalities in mitochondrial encephalomyopathies.

Localized brain proton MR spectra were acquired from patients with different mitochondrial encephalomyopathies (myoclonus epilepsy with ragged-red fibers [MERRF], Kearns-Sayre syndrome [KSS], and mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes [MELAS]). The regional brain metabolic abnormalities in patients with these syndromes showed different features consistent with the distinct phenotypes. In MERRF, only one of four patients showed an increase in the lactate/creatine resonance intensity ratio (an index of impairment of oxidative metabolism) in spectra from central (supraventricular) or occipital brain volumes, and this was small.