Clinical evaluation of renovascular hypertension and therapeutic decisions

The renal arteriogram alone, useful as an anatomic guide for the surgeon or radiologist, is inadequate to predict potential blood pressure reversal by correction of the obstructing lesion. A patient must be identified as having functionally significant renal arterial disease before intervention can be recommended. The authors discuss uncovering functionally significant renal artery stenosis, the pathophysiology of experimental Goldblatt hypertension, and criteria to identify renovascular hypertension, including peripheral plasma renin activity and differential renal-vein renin determinations.     

Serum cholesterol esterifying and cholesteryl ester hydrolyzing activities in liver diseases: relationships to cholesterol, bilirubin, and bile salt concentrations

Patients with acute hepatitis and chronic alcoholic liver disease had decreased net serum cholesterol esterifying activity (CEA) which correlated positively with the percentages and concentrations of cholesteryl esters in their serum. These cholesterol parameters also correlated negatively with serum bilirubin concentrations, but bilirubin added to sera in vitro failed to influence CEA. The decreased net CEA in the patients was not due to its inhibition by serum bile salts. The sera from five patients catalyzed a net hydrolysis of cholesteryl esters rather than a net esterification of free cholesterol. Since serum cholesteryl ester hydrolase activity may also have been present in the patients with decreased CEA, net CEA cannot be equated with the activity of lecithin-cholesterol acyl transferase (LCAT) in patients with liver disease. The relative contributions of LCAT and cholesteryl ester hydrolase activities to CEA in disease states remain to be evaluated by mutually independent assays. Nevertheless, the correlations found between net CEA and the concentrations and percentages of cholesteryl esters support the concepts that serum cholesterol esterifying activity is physiologically important in the formation of serum cholesteryl esters and that decreased CEA is one mechanism for the decreased level of cholesteryl esters seen in patients with liver diseases.     

Hepatitis A: the burden among Latino children in California

OBJECTIVE: To determine the prevalence of Hepatitis A within subpopulations of southern California counties. MATERIAL AND METHODS: Age and race/ethnic-specific hepatitis A rates were derived from the California Department of Health Services Surveillance and Statistics Section for 1996-2001 and from demographic data of the California Department of Finance. RESULTS: 2.3 million Latino children (aged 0-14 years) in five southern California counties had a rate of 31.1 cases per 100,000, five times higher than the non-Hispanic white rate. CONCLUSION: The CDC Advisory Committee on Immunization Practices recommends routine vaccination for children with "very high" rates of hepatitis A. The annual prevalence of hepatitis A in California, especially in southern California, met the CDC's "very high" definition, therefore Latino children in these counties should be considered for routine childhood hepatitis A vaccination. As health has no borders, this issue should be addressed by the public health services of both, the United States' and Mexico's public health services.     

Monochorionic triplets after single embryo transfer

A 40-year-old patient underwent intracytoplasmic sperm injection and assisted hatching, and a single embryo was transferred. Ultrasonography demonstrated a single gestational sac containing monochorionic tri-amniotic pregnancy. Several factors that have been implicated in the aetiology of monozygotic triple pregnancies after IVF appear to be present in this case. To avoid multiple pregnancies after IVF, it is time to have definite predictive factors for the occurrence of monozygotic multiple pregnancies as well as transferring only a single embryo.     

Gastric activity studies using a magnetic tracer

A magnetic pulse generator has been set up in order to study gastric activity. Two coils 1.05 m in diameter, arranged in a Helmholtz configuration, were used. The system generated magnetic field pulses higher than 15 mT, of duration 17.3+/-1.2 ms. Measurements were performed in 11 male volunteers, with average age 29.3+/-6.4 years and body mass index 26.0+/-4.8 kg m(-2). Magnetite (Fe3O4) particles with diameters from 75 to 125 microm were used as magnetic tracers, which were mixed in 250 ml of yogurt in concentrations from 2 to 5 g. Signals were registered by using a high speed 3 axis fluxgate digital magnetometer and processed to determine the relaxation of the magnetic tracers by fitting a first-order exponential function to the data, a mean relaxation constant K = 116+/-40 s(-1) was obtained. Also, an average gastric peristaltic frequency was measured; a value of 3.2+/-0.3 cpm was determined.     

Neural progenitor cells do not differentiate prematurely in presenilin-1 null mutant mice

Mice with a null mutation of the presenilin-1 (PS1-/-) gene die during late intrauterine life or shortly after birth and exhibit defects in cortical development. A previous report suggested that neurons differentiate prematurely in PS1-/- brain [M. Handler, X. Yang, J. Shen, Presenilin-1 regulates neuronal differentiation during neurogenesis, Development 127 (2000) 2593-2606]. Here we reexamined the issue of whether premature neuronal differentiation occurs in PS1-/- brain using fresh cell suspensions from embryonic E11.5 and E13.5 telencephalon where individual cell phenotypes can be easily determined with cell type specific markers. Immunostaining with seven neuronal specific markers (MAP2, beta-III tubulin, GABA, reelin, GluR2/3, calbindin, and calretinin) failed to reveal any evidence of premature neuronal differentiation in PS1-/- telencephalon. We also determined the fraction of cells expressing the neural progenitor marker nestin and found no evidence for premature depletion of neural progenitor cells in PS1-/- telencephalon. Moreover, based on MAP2 staining of tissue sections from E12.5 embryos the topography of newly generated neurons also appeared to be undisturbed in the telencephalon of PS1-/- embryos. These studies thus argue that premature neuronal differentiation is unlikely to be a core pathophysiological feature underlying the aberrant cortical development that occurs in PS1-/- brain.