BACKGROUND The kidneys ability to concentrate and dilute urine is deteriorated during progressive renal insufficiency. We wanted to test the hypothesis that these phenomena could be attributed to an abnormal function of the principal cells in the distal part of the nephron. METHODS Healthy control subjects and patients with chronic kidney diseases were studied. Group 1 comprised healthy subje...

The influence of protein kinase C (PKC) activation on cyclic AMP production in GH3 cells has been studied. The stimulation of cyclic AMP accumulation induced by forskolin and cholera toxin was potentiated by 4 beta-phorbol 12,13-dibutyrate (PDBu). Moreover, PDBu, which causes attenuation of the maximal response to vasoactive intestinal polypeptide (VIP), also induced a small right shift in the ...

Kinetic studies with platelet AMP deaminase, at pH 7.0 and 100 mM NaC1, gave cooperative initial velocity curves with AMP as substrate, with Mg-ATP2- as an activator, and with Pi as an inhibitor. In the absence of Mg-ATP2-, the s0.5 for AMP was 4.5 mM with a Hill coefficient approaching 2.0. In the presence of saturating Mg-ATP2-, the s0.5 for AMP was reduced to 0.18 mM, the maximum velocity wa...

{sl let $[n]={1,dots, n}$ be colored in $k$ colors. a rainbow ap$(k)$ in $[n]$ is a $k$ term arithmetic progression whose elements have different colors. conlon, jungi'{c} and radoiv{c}i'{c} cite{conlon} prove that there exists an equinumerous 4-coloring of $[4n]$ which is rainbow ap(4) free, when $n$ is even. based on their construction, we show that such a coloring of ...

The hydrolysis of adenosine 3':5'-monophosphate by the high Km cyclic nucleotide phosphodiesterase of bakers' yeast was studied over a range of temperature and pH at I = 0.17. The effects of ionic strength and MgCl2 concentration were studied at pH 7.7 and 30 degrees C. Km and Vmax were insensitive to changes in the MgCl2 concentration between 1 and 30 mM, implying that this enzyme (which does ...

An EDTA procedure was used to prepare isolated epithelial cells of human gallbladder devoid of endogenous vasoactive intestinal peptide (VIP) as measured by radioimmunoassay. Specific binding sites for VIP were characterized in these cells. At 37 degrees C, the binding of (125)I-labeled VIP reached a peak within 20 min and then declined rapidly. At 15 degrees C, binding was stable between 90 an...

Vitamin C (ascorbic acid, AA) is a cofactor for many important enzymatic reactions and a powerful antioxidant. AA provides protection against oxidative stress by acting as a scavenger of reactive oxygen species, either directly or indirectly by recycling of the lipid-soluble antioxidant, α-tocopherol (vitamin E). Only a few species, including humans, guinea pigs, and zebrafish, cannot synthesiz...

Small cyclic nucleotide derivatives are employed as second messengers by both prokaryotes and eukaryotes to regulate diverse cellular processes responding to various signals. In bacteria, c-di-AMP has been discovered most recently, and some Gram-positive pathogens including S. pyogenes use this cyclic nucleotide derivative as a second messenger instead of c-di-GMP, a well-studied important bact...

Since 2015, Côte d’Ivoire has been the world’s largest cashew producer. However, orchards in are infected by fungal diseases that weaken production. And contribution of weeds to spread these is not yet understood. This study was initiated with aim establishing role proliferation pathogenic fungi orchards. It consisted a survey showing disease symptoms from February 2021 July 2022. The itinerant...

The Upper Guinea Forest is subject to heavy deforestation. In this context, many endemic and/or rare plant species are threatened with extinction. This the case of Aubregrinia taïensis (Aubrév. & Pellegr.) Heine, a critically endangered Sapotaceae species, Côte d’Ivoire and Ghana. After 3 years investigation in around Tai National Park (TNP) West d’Ivoire, only one individual was located no sex...