Search results for "Secretion"

Frequency-dependent effects of activation and inhibition of protein kinase C on neurohypophysial release of oxytocin and vasopressin

1989

Isolated rat neurohypophyses were superfused in vitro and the release of vasopressin and oxytocin into the medium was determined by specific radioimmunoassays. Hormone secretion was increased by electrical stimulation of the pituitary stalk at different frequencies. The effects of several phorbol esters, known to activate (phorbol 12,13-dibutyrate, PDB) or not to affect (4a-phorbol 12,13-dideconate and phorbol 12-monoacetate) protein kinase C, and of the direct protein kinase C inhibitor 1-(5-isoquinolinylsulfonyl)-2-methylpiperazine (H7) were tested. Electrical stimulation with 450 pulses caused the release of about 45 μU vasopressin and 55 μU oxytocin, when a frequency of 3 Hz was applied…

Basal growth hormone concentrations in blood and the risk for prostate cancer: A case-control study

2005

OBJECTIVE To assess the relationship between basal serum growth hormone (GH) levels and prostate cancer risk. METHODS We conducted a population-based case-control study; cases included 68 men, aged 45–85 years, diagnosed with incident, primary, histologically confirmed, and clinically apparent (stage B and higher) prostate cancer. Controls included 240 men, frequency matched on age and residential area. Age, race, BMI, waist circumference, history of enlarged prostate, education, and current smoking status, were all considered as possible confounders. RESULTS We found a statistically significant trend of decreasing prostate cancer risk across increasing GH quintiles, in both crude (OR: 0.31…

Exercise cardiac power and the risk of heart failure in men: A population-based follow-up study.

2019

Little is known about exercise cardiac power (ECP), defined as the ratio of directly measured maximal oxygen uptake with peak systolic blood pressure during exercise, on heart failure (HF) risk. We examined the association of ECP and the risk of HF.This was a population-based cohort study of 2351 men from eastern Finland. The average time to follow-up was 25 years. Participants participated at baseline in an exercise stress test. A total of 313 cases of HF occurred.Men with low ECP (9.84 mL/mmHg, the lowest quartile) had a 2.37-fold (95% confidence interval (95%CI): 1.68-3.35, p0.0001) hazards ratio of HF as compared with men with high ECP (13.92 mL/mmHg, the highest quartile), after adjust…

Nonlinearities in amoxycillin pharmacokinetics. I. Disposition studies in the rat.

1992

Several features of amoxycillin pharmacokinetics in man are not well known in spite of the extensive clinical use of the antibiotic. In this paper it is demonstrated that amoxycillin disposition kinetics in rats is clearly nonlinear, and that this may be due mainly to its elimination mechanisms. At different intravenous bolus dose levels, and in steady-state perfusion studies, the most striking feature is an increased renal clearance as dose increases (from 3.5 to 7.0 mg kg-1 for intravenous bolus, and from 4.6 to 20.0 micrograms min-1 for intravenous perfusions). This phenomenon has been attributed to a saturation of the active renal tubular reabsorption of the antibiotic. When the intrave…

Mass Transport Analysis of the Enhanced Buffer Capacity of the Bicarbonate-CO2 Buffer in a Phase-Heterogenous System: Physiological and Pharmaceutica…

2018

The bicarbonate buffer capacity is usually considered in a phase-homogeneous system, at equilibrium, with no CO2 transfer between the liquid buffer phase and another phase. However, typically, an in vitro bicarbonate buffer-based system is a phase-heterogeneous system, as it entails continuously sparging (bubbling) the dissolution medium with CO2 in a gas mixture, at constant ratio, to maintain a constant partial pressure of CO2 (g) and CO2(aq) molarity at a prescribed value, with CO2 diffusing freely between the gas and the aqueous phases. The human gastrointestinal tract is also a phase-heterogeneous system, with CO2 diffusing across the mucosal membrane into the mesenteric arterial blood…

Mast Cell Proteases Stimulate Neurogenic and Non-Neurogenic Mucosal Chloride Secretion in Guinea Pig Distal Ileum.

2009

Localized Liquid Secretion from a Photopatterned Liquid-Crystal Polymer Skin

2020

Liquid-releasing artificial skins are made from films made of a smectic liquid-crystal polymer network (LCN) photopolymerized in the presence of a photoactive azobenzene chromophore and a liquid-crystal porogen. The nonreactive porogen phase separates during the polymerization process, and the polymer forms a spongy polymer network filled with liquid. The liquid is excreted from the film when exposed to UV light upon conversion of trans-azobenzene to its cis isomer. Here, localized liquid secretion at preset positions at the polymer film is described. The design principle is based on creating a hybrid molecular architecture with both smectic and nonordered isotropic alignments in a continuo…

High frequencies of antibiotic resistance genes in infants' meconium and early fecal samples

2016

The gastrointestinal tract (GIT) microbiota has been identified as an important reservoir of antibiotic resistance genes (ARGs) that can be horizontally transferred to pathogenic species. Maternal GIT microbes can be transmitted to the offspring, and recent work indicates that such transfer starts before birth. We have used culture-independent genetic screenings to explore whether ARGs are already present in the meconium accumulated in the GIT during fetal life and in feces of 1-week-old infants. We have analyzed resistance to β-lactam antibiotics (BLr) and tetracycline (Tcr), screening for a variety of genes conferring each. To evaluate whether ARGs could have been inherited by maternal tr…

The G428A Nonsense Mutation in FUT2 Provides Strong but Not Absolute Protection against Symptomatic GII.4 Norovirus Infection

2009

In November 2004, 116 individuals in an elderly nursing home in El Grao de Castellón, Spain were symptomatically infected with genogroup II.4 (GII.4) norovirus. The global attack rate was 54.2%. Genotyping of 34 symptomatic individuals regarding the FUT2 gene revealed that one patient was, surprisingly, a non-secretor, hence indicating secretor-independent infection. Lewis genotyping revealed that Lewis-positive and negative individuals were susceptible to symptomatic norovirus infection indicating that Lewis status did not predict susceptibility. Saliva based ELISA assays were used to determine binding of the outbreak virus to saliva samples. Saliva from a secretor-negative individual boun…

Gamma-Interferon Regulates Secretion of G-CSF in Human Monocytes on the Transcriptional Level

1987

The production of colony stimulating factors (CSF) for granulocytes and monocytes is integrated into a network of communicating soluble messenger molecules resulting from T-cell/monocyte interactions. We assessed the capactiy of gamma-Interferon to modulate monocyte secretion of CSF by colony assays and Northern blot analysis to hybridize monocyte RNA with cDNA probes of different CSF-types. Whereas mRNA for GM-CSF was undetectable in untreated and gamma-IFN treated peripheral blood monocytes, the constitutive expression of mRNA for G-CSF and subsequent production of a CSF with biological activities similar to G-CSF could highly be enhanced by exposure of monocytes to gamma-IFN.