[Hypercalciuria].

P Houillier; H Boulanger

Home/Archive/PubMed

PubMed · 9781174

[Hypercalciuria].

P Houillier·H Boulanger

View original source ↗Export metadata ↓

Abstract

Hypercalciuria is a very frequent disorder that is defined by a daily calcium excretion rate in excess of 0.1 mmol/kg. Whatever its mechanism, it always expresses an increased input of calcium in extracellular fluid, from intestine and (or) bone. In few instances, hypercalciuria is secondary to an underlying disease that needs to be identified (primary hyperparathyroidism, cancer, granulomatosis...). However, in most cases, it is a primary (idiopathic) disorder that reveals an abnormal handling of calcium by intestinal and renal tubular epithelia. It is then treated by a restricted dietary supply in sodium and animal proteins, and by the use of thiazide diuretics.

Explore related subjects

Absorption Calcium Extracellular Space Humans Intestinal Mucosa Kidney Tubules Journal Article Review

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

P Houillier, H Boulanger. 1998-06-01. [Hypercalciuria].. https://pubmed.ncbi.nlm.nih.gov/9781174/

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2000

Optical properties of Nannochloropsis sp and their application to remote estimation of cell mass.

The absorption and scattering coefficients and reflectance spectra of ultra-high density Nannochloropsis occulata cultures were investigated in detail to identify the optical properties of the cultures and devise algorithms for remote estimation of dry cell mass in ultra-high cell density cultures. High-spectral resolution measurements of apparent absorption and attenuation as well as reflectance from 400 to 900 nm were carried out in relation to the dry weight, cell count, and pigment concentration in outdoor cultures. Indices calculated as (R(NIR) - R(red))/(R(NIR) + R(red)) and R(NIR)/R(red), in which R(NIR) is reflectance in the range from 750 to 800 nm and R(red) is reflectance in the range 670-680 nm, were used for remote assessment of dry cell mass. Remote estimation in the range 1 to 8 g/L was accomplished with an error of less than 0.66 g/L. A different index, i.e., (R(NIR) - R(red)) was employed for estimation of cell-chlorophyll concentration. This is the first report of in vivo specific absorption coefficient of chlorophyll-a and specific scattering coefficient per dry algal weight of Nannochloropsis sp., providing a basis for remote monitoring of dense phytoplankton masses.

Absorption↗

PubMed2000

Hydrolytic activity in baker's yeast limits the yield of asymmetric 3-oxo ester reduction.

Microbial reductions of ketones hold great potential for the production of enantiopure alcohols, as long as highly selective redox enzymes are not interfered with by competing activities. During reduction of ethyl 3-oxobutanoate by baker's yeast (Saccharomyces cerevisiae) to ethyl (S)-3-hydroxybutanoate, a high enantiomeric excess (> 99%) can be obtained. However, reported yields do not exceed 50-70%. In this article, three main causes are shown to be responsible for these low to moderate yields. These are evaporation of the substrate and product esters, absorption or adsorption of the two esters by the yeast cells and hydrolysis of the two esters by yeast enzymes. The hydrolysis products are further metabolized by the yeast. By reducing the evaporation and absorption losses, the reduction yield can easily be improved to about 85%. Improvement of the efficiency of the reduction and hence the reduction/hydrolysis ratio should lead to a further increase in yield.

Absorption↗

PubMed2000

Immobilization of alliinase on porous aluminum oxide.

Membrane filters prepared from porous aluminum oxide (Anopore) were investigated for their potential use as a durable support for enzymes. Alliinase (EC 4.4.1.4) was chosen as a model enzyme for immobilization experiments. To allow for smooth fixation, the enzyme was immobilized indirectly by sugar-lectin binding. Monomolecular layers of the lectin concanavalin A and alliinase were applied by self-assembling processes. As an anchor for these layers, the sugar, mannan, was covalently coupled to the membrane surface. This procedure exhibits several advantages: (i) enzyme immobilization can be carried out under smooth conditions; (ii) immobilization needs little time; and (iii) protein layers may be renewed.

Absorption↗