Studies on ion movement in malpighian tubules of locusta migratoria l. with particular reference to electrical events

Intracellular microelectrodes have been used in conjunction with ion substitution, and agonists and inhibitors of known transport processes to investigate the mechanisms whereby ions cross the basal and apical cell membranes of the Malpighian tubules of Locusta. Values for basal, apical and transepithelial potentials in 'Normal' saline were -71.6 ± 0.3 mV, -82.6 ± 0.8 mV and +5.7 ± 1.0 mV (lumen positive) respectively. Ion substitution experiments, involving Na(^+),K(^+) and C1(^-) in the bathing media, indicated that the basal membrane was more permeable to K(^+) than Na(^+) and C1(^-). Two different electrical responses to high [K(^+)](_o) saline (the Type A and Type B response) were noted and these probably reflect distinct physiological states of basal membrane permeability. Experiments with ouabain and vanadate suggested that whilst Na(^+)+K(^+) ATPase activity, which has been demonstrated in microsomal preparations, was not significantly electrogenic, asymmetric ionic distribution across the basal membrane was partly maintained by thisenzyme Furthermore, 3-H ouabain-binding studies indicated that Na(^+)+K(^+) exchange 'pump' turnover was adequate to account for substantial entry and Na^ exit across the basal membrane. The electrochemicalgradient across the apical membrane suggests that exit from the cell must involve an active process with CI following passively. Data from ion substitution experiments and treatment with furosemide and bumetanide suggest that CI entry across the basalmembrane may be via cotransport with Na^ and/or K^. However, the+ —differential electrical responses to Na(^+) free and C1(^-) free salines question the role of Na(^+) in this process. The effects of c AMP, Ca(^2+) substitution and various inhibitors on basal and apical membrane potentials, taken in conjunction with the results referred to above, are discussed and a hypothetical model proposed whereby changes in intracellular Ca(^2+) and c AMP effect control of ion movements across the two cell surfaces

A Chronic Oral Toxicity Study of Marine Collagen Peptides Preparation from Chum Salmon (Oncorhynchus keta) Skin Using Sprague-Dawley Rat

Due to the increased consumption of marine collagen peptides preparation (MCP) as ingredients in functional foods and pharmaceuticals, it was necessary to carry out safety requirements in the form of an oral chronic toxicity assessment. In order to define the oral chronic toxicity of MCP, a 24-month feeding study of MCP was carried out. Sprague-Dawley (S-D) rats at the age of four-week of both sexes were treated with MCP at the diet concentrations of 0%, 2.25%, 4.5%, 9% and 18% (wt/wt). The actual food intake and bodyweight of the individual animals were recorded periodically until sacrifice. Blood and urine samples were collected for serum chemistry evaluations and urinalysis. Throughout the experimental period, there was no toxicologically significant difference between the vehicle and MCP-treated animals with respect to the survival rate, body weight, food consumption, urinalysis, clinical biochemistry parameter and relative organ weight in either sex. Moreover, incidences of non-neoplastic lesions in MCP-treated groups did not significantly increase compared with the control group. Under the present experimental conditions, no higher risk of chronic toxic effects was observed in MCP-treated rats at the diet concentrations of 2.25%, 4.5%, 9% and 18% (wt/wt) than in the rats fed with basal rodent diet

Impact of a (poly)phenol-rich extract from the brown algae Ascophyllum nodosum on DNA damage and antioxidant activity in an overweight or obese population: a randomized controlled trial

Background Epidemiologic evidence suggests that a diet rich in (poly)phenols has beneficial effects on many chronic diseases. Brown seaweed is a rich source of (poly)phenols. Objective The aim of this study was to investigate the bioavailability and effect of a brown seaweed (Ascophyllum nodosum) (poly)phenol extract on DNA damage, oxidative stress, and inflammation in vivo. Design A randomized, double-blind, placebo-controlled crossover trial was conducted in 80 participants aged 30–65 y with a body mass index (in kg/m2) ≥25. The participants consumed either a 400-mg capsule containing 100 mg seaweed (poly)phenol and 300 mg maltodextrin or a 400-mg maltodextrin placebo control capsule daily for an 8-wk period. Bioactivity was assessed with a panel of blood-based markers including lymphocyte DNA damage, plasma oxidant capacity, C-reactive protein (CRP), and inflammatory cytokines. To explore the bioavailability of seaweed phenolics, an untargeted metabolomics analysis of urine and plasma samples after seaweed consumption was determined by ultra-high-performance liquid chromatography–high-resolution mass spectrometry. Results Consumption of the seaweed (poly)phenols resulted in a modest decrease in DNA damage but only in a subset of the total population who were obese. There were no significant changes in CRP, antioxidant status, or inflammatory cytokines. We identified phlorotannin metabolites that are considered potential biomarkers of seaweed consumption including pyrogallol/phloroglucinol-sulfate, hydroxytrifurahol A-glucuronide, dioxinodehydroeckol-glucuronide, diphlorethol sulfates, C-O-C dimer of phloroglucinol sulfate, and C-O-C dimer of phloroglucinol. Conclusions To the best of our knowledge, this work represents the first comprehensive study investigating the bioactivity and bioavailability of seaweed (poly)phenolics in human participants. We identified several potential biomarkers of seaweed consumption. Intriguingly, the modest improvements in DNA damage were observed only in the obese subset of the total population. The subgroup analysis should be considered exploratory because it was not preplanned; therefore, it was not powered adequately. Elucidation of the biology underpinning this observation will require participant stratification according to weight in future studies. This trial was registered at clinicaltrials.gov as NCT02295878

Chitosan Modification and Pharmaceutical/Biomedical Applications

Chitosan has received much attention as a functional biopolymer for diverse applications, especially in pharmaceutics and medicine. Our recent efforts focused on the chemical and biological modification of chitosan in order to increase its solubility in aqueous solutions and absorbability in the in vivo system, thus for a better use of chitosan. This review summarizes chitosan modification and its pharmaceutical/biomedical applications based on our achievements as well as the domestic and overseas developments: (1) enzymatic preparation of low molecular weight chitosans/chitooligosaccharides with their hypocholesterolemic and immuno-modulating effects; (2) the effects of chitin, chitosan and their derivatives on blood hemostasis; and (3) synthesis of a non-toxic ion ligand—D-Glucosaminic acid from Oxidation of D-Glucosamine for cancer and diabetes therapy

Dwelling in Strangeness: accounts of the Kingsley Hall Community, London (1965-1970)

This article explores archival accounts of the experimental community, Kingsley Hall (1965-70), established by R. D. Laing, the radical Scottish psychiatrist. The paper contributes to renewed interest in Kingsley Hall, R. D. Laing's radical psychiatry and UK counterculture. Archival sources enable not only the further exploration of already known figures but also let us hear previously unheard voices. Following a discussion of archival materials, the Hall is analyzed thematically and historically as (i) an inner spaceship; (ii) an embattled middle-class countercultural plantation; (iii) a site of spiritual renewal and development; (iv) a single-building arts colony; and (v) a countercultural experiment. Finally, it is argued that with re-evaluation of 1960s and 1970s counterculture now underway on the Left, the Hall’s experiment in Laingian countercultural psychiatry—as we may fittingly call it—may yet inform future radical projects (in mental health and beyond)

Combining vitamin C and carotenoid biomarkers better predicts fruit and vegetable intake than individual biomarkers in dietary intervention studies.

The aim of this study was to determine whether combining potential biomarkers of fruit and vegetables is better at predicting FV intake within FV intervention studies than single biomarkers