scholarly journals A trial of zinc supplementation in young rural Gambian children

1993 ◽  
Vol 69 (1) ◽  
pp. 243-255 ◽  
Author(s):  
C. J. Bates ◽  
P. H. Bates ◽  
M. Dardenne ◽  
A. Prentice ◽  
P. G. Lunn ◽  
...  
Keyword(s):  
Failure To Thrive ◽  
Linear Increase ◽  
Secretory Iga ◽  
Seasonal Effect ◽  
Zn Deficiency ◽  
Arm Circumference ◽  
Zn Status ◽  
Biochemical Indices

The present study tested the hypothesis that inadequate Zn intake might be responsible for failure to thrive and impaired catch-up growth in young rural Gambian children, and that Zn supplements might be beneficial. Gambian children might be deprived of Zn because of its poor availability from their predominantly plant-based diet. Rural Gambian children (110; fifty boys, sixty girls) aged between 0.57 and 2.30 years were divided into two matched groups, one to receive 70 mg Zn twice weekly for 1.25 years, and the other a placebo. Growth and mid-upper-arm circumference were measured at weekly intervals throughout the study and illnesses were monitored. Capillary blood and urine samples were collected at 0, 2 and 8 weeks. Body weights and arm circumferences showed a linear increase, plus a seasonal effect (rainy season faltering). For body weight there was no significant overall effect of the supplement. For arm circumference, a very small (2 %) but significant (P < 0.01) difference favoured the supplemented group. Plasma thymulin was much lower at the first clinic than at the second and third clinics, and in vitro Zn stimulation was greater at the first clinic. There was, however, no effect of Zn in vivo. Likewise, Zn did not significantly benefit T-cell numbers or ratios, secretory IgA in urine, circulating hormone levels or biochemical indices of Zn status. One index of intestinal permeability, i.e. lactulose: creatinine, was improved (P < 0.02) by the supplement, but the lactulose: mannitol value was not; this requires further investigation. Dietary Zn deficiency is, thus, unlikely to be of major overall importance for rural Gambian children's ability to thrive, and blanket Zn supplementation is not justified. There may, however, be vulnerable sub-groups who would benefit from Zn supplements.

Age-dependent changes in volume and haemoglobin content of erythrocytes in the carp (Cyprinus carpio L.)

1989 ◽  
Vol 141 (1) ◽  
pp. 133-149 ◽  
Author(s):  
W. Speckner ◽  
J. F. Schindler ◽  
C. Albers
Keyword(s):  
Gel Filtration ◽  
Linear Increase ◽  
Human Erythrocytes ◽  
Main Peak ◽  
Red Cell ◽  
Human Haemoglobin ◽  
Cell Fractions ◽  
Haemoglobin Content

Carp erythrocytes were fractionated by angle-head centrifugation which yielded fractions with a linear increase in density. Haematological examinations revealed that the heavier red blood cells of carp had greater volumes (MCV), more haemoglobin (MCH) and higher haemoglobin concentrations (MCHC) than light ones. The same experiments with human red cell fractions yielded a decrease in MCV, constant MCH and an increase in MCHC. Haemoglobin content in individual erythrocytes was also determined by scanning stage absorbance cytophotometry to establish the frequency distribution of the cellular haemoglobin contents. In carp, the distribution was symmetrical with the means increasing with density. No such change with cell density was found in human erythrocytes. Both carp and human erythrocytes incorporated [2-14C]glycine in vitro. After gel filtration, radioactivity was detected in carp, but not in human, haemoglobin fractions. 14C was found in all three haemoglobin fractions, obtained by isoelectric focusing, and was present in the haem and in the globin. [2-14C]glycine-labelled erythrocytes were reinjected into chronically cannulated carp and followed in vivo for several months. With time, the main peak of scintillation counts shifted from red cell fractions of low to high density. This is considered as evidence that density and age of red cells in carp are positively correlated and that erythrocytes can synthesize haemoglobin while circulating in the peripheral blood.

scholarly journals Group A Streptococcus AdcR Regulon Participates in Bacterial Defense against Host-Mediated Zinc Sequestration and Contributes to Virulence

2020 ◽  
Vol 88 (8) ◽  
Author(s):  
Nishanth Makthal ◽  
Hackwon Do ◽  
Brian M. Wendel ◽  
Randall J. Olsen ◽  
John D. Helmann ◽  
...  
Keyword(s):  
Pathogenic Bacteria ◽  
Group A Streptococcus ◽  
Zn Deficiency ◽  
Direct Competition ◽  
Mutant Strains ◽  
Genes Encoding ◽  
Group A ◽  
Gas Interactions

ABSTRACT Colonization by pathogenic bacteria depends on their ability to overcome host nutritional defenses and acquire nutrients. The human pathogen group A streptococcus (GAS) encounters the host defense factor calprotectin (CP) during infection. CP inhibits GAS growth in vitro by imposing zinc (Zn) limitation. However, GAS counterstrategies to combat CP-mediated Zn limitation and the in vivo relevance of CP-GAS interactions to bacterial pathogenesis remain unknown. Here, we report that GAS upregulates the AdcR regulon in response to CP-mediated Zn limitation. The AdcR regulon includes genes encoding Zn import (adcABC), Zn sparing (rpsN.2), and Zn scavenging systems (adcAII, phtD, and phtY). Each gene in the AdcR regulon contributes to GAS Zn acquisition and CP resistance. The ΔadcC and ΔrpsN.2 mutant strains were the most susceptible to CP, whereas the ΔadcA, ΔadcAII, and ΔphtD mutant strains displayed less CP sensitivity during growth in vitro. However, the ΔphtY mutant strain did not display an increased CP sensitivity. The varied sensitivity of the mutant strains to CP-mediated Zn limitation suggests distinct roles for individual AdcR regulon genes in GAS Zn acquisition. GAS upregulates the AdcR regulon during necrotizing fasciitis infection in WT mice but not in S100a9−/− mice lacking CP. This suggests that CP induces Zn deficiency in the host. Finally, consistent with the in vitro results, several of the AdcR regulon genes are critical for GAS virulence in WT mice, whereas they are dispensable for virulence in S100a9−/− mice, indicating the direct competition for Zn between CP and proteins encoded by the GAS AdcR regulon during infection.

Review: Gp-340/DMBT1 in mucosal innate immunity

2010 ◽  
Vol 16 (3) ◽  
pp. 160-167 ◽  
Author(s):  
Jens Madsen ◽  
Jan Mollenhauer ◽  
Uffe Holmskov
Keyword(s):  
Innate Immunity ◽  
Influenza A ◽  
Research Field ◽  
Secretory Iga ◽  
Functional Studies ◽  
Gram Positive Bacteria ◽  
Alternatively Spliced ◽  
Trefoil Factor 2

Deleted in Malignant Brain Tumour 1 (DMBT1) is a gene that encodes alternatively spliced proteins involved in mucosal innate immunity. It also encodes a glycoprotein with a molecular mass of 340 kDa, and is referred to as gp-340 (DMBT1gp340) and salivary agglutinin (DMBT1SAG). DMBT1gp340 is secreted into broncho-alveolar surface lining fluid whereas DMBTSAG is present in the saliva. The two molecules were shown to be identical and both interact with and agglutinate several Gram-negative and Gram-positive bacteria including Streptococcus mutans, a bacterium responsible for caries in the oral cavity. DMBT1gp340 interacts with surfactant proteins A and D (SP-D). DMBT1gp340 and SP-D can individually and together interact and agglutinate influenza A virus. DMBT1gp340 also binds to HIV-1 and facilitates transcytosis of the virus into epithelial cells. DMBT1 binds to a variety of other host proteins, including serum and secretory IgA, C1q, lactoferrin, MUC5B and trefoil factor 2 (TFF2), all molecules with involvement in innate immunity and/or wound-healing processes. Recent generation of Dmbt1-deficient mice has provided the research field of DMBT1 with a model that allows research to progress from in vitro studies to in vivo functional studies of the multifunctional proteins encoded by the DMBT1 gene.

A Comparison of the Clearance of Urographic Contrast Medium (Sodium Diatrizoate) by Peritoneal and Haemodialysis

1976 ◽  
Vol 50 (1) ◽  
pp. 69-74
Author(s):  
P. Ackrill ◽  
C. S. McIntosh ◽  
C. Nimmon ◽  
L. R. I. Baker ◽  
W. R. Cattell
Keyword(s):  
Peritoneal Dialysis ◽  
Plasma Flow ◽  
Extracellular Fluid ◽  
Linear Increase ◽  
Urea Clearance ◽  
Clearance Ratio ◽  
Significant Difference ◽  
Rapid Removal

1. The clearance of isotopically labelled sodium diatrizoate by haemodialysis was measured in vitro, with simulated extracellular fluid, and in vivo in eleven patients, at varying rates of fluid or plasma flow. Clearance was also measured in five patients undergoing peritoneal dialysis. In all instances simultaneous measurements of urea clearance were made and the diatrizoate/urea clearance ratio was calculated. 2. In haemodialysis studies, diatrizoate and urea clearances showed a linear increase with increasing ‘extracellular fluid’ or plasma flow through the dialyser while the diatrizoate/urea clearance ratio fell. 3. The clearance of diatrizoate in vivo was slightly less than clearance in vitro at corresponding flow rates, but the diatrizoate/urea clearance ratio showed no significant difference. 4. Diatrizoate and urea clearances during peritoneal dialysis were very much lower than during haemodialysis but the diatrizoate/urea clearance ratios were within the same range. 5. The rapid removal of diatrizoate in patients with renal failure requires haemodialysis.

scholarly journals Expression, purification and biochemical characterization of recombinant murine secretory component: a novel tool in mucosal immunology

1999 ◽  
Vol 341 (2) ◽  
pp. 299-306 ◽  
Author(s):  
Pascal CROTTET ◽  
Sandra COTTET ◽  
B CORTHÉSY
Keyword(s):  
Biochemical Characterization ◽  
Cell Clone ◽  
Recombinant Vaccinia Virus ◽  
Secretory Component ◽  
Secretory Iga ◽  
Molecular Forms ◽  
Receptor Interaction ◽  
Function Relationship

Reconstitution of secretory IgA (S-IgA) by the association in vitro of secretory component (SC) and polymeric IgA (pIgA) obtained from hybridomas is a valuable tool in the study of the structure-function relationship in this particular class of antibody. Although dimeric IgA (dIgA) can be obtained and purified from hybridoma clones, SC remains tedious to isolate in sufficient amounts from colostral milk. Several murine models for the study of mucosal immunity are available, which could potentially benefit from the use of cognate IgA antibodies in various molecular forms, including dIgA and S-IgA. We report here on the establishment of two expression systems allowing the production of milligram amounts of pure recombinant murine SC (rmSC) with preserved murine pIgA-binding capability. The first system relies on the use of recombinant vaccinia virus to prompt infected HeLa cells to express the murine SC protein, whereas the second system is based on a stably transfected cell clone exhibiting murine glycosylation. The second source of rmSC will permit the study of the role of its sugar moieties in pathogen-host interactions, and the evaluation of its function in passive protection without risking adverse immune responses. The extensive biochemical characterization conducted in this study demonstrates that rmSC is a dependable and convenient alternative to the natural product, and indicates that the J chain is dispensable in the recognition of pIgA and SCin vitro, whereas it is required for proper pIgA-polymeric Ig receptor interaction in vivo.

EFFECTS OF LONG-TERM TREATMENT AND OF LOW CONCENTRATIONS OF THYROID HORMONES ON THE OXYGEN UPTAKE OF TOAD TISSUES

1966 ◽  
Vol 36 (3) ◽  
pp. 221-229 ◽  
Author(s):  
C. C. THORNBURN ◽  
A. J. MATTY
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Bufo Bufo ◽  
Term Treatment ◽  
Seasonal Effect ◽  
Long Term Treatment ◽  
Wide Range ◽  
Two Peaks

SUMMARY Isolated tissues of the toad Bufo bufo (urinary bladder, skin and kidney) were treated in vitro with thyroxine (T4) or tri-iodothyronine (T3) both with and without prior administration of the hormones in vivo. They were incubated at low temperature, and their oxygen consumption studied for 48 hr. Both hormones had little effect in vitro. Pretreatment with T4 in vivo usually lowered oxygen uptake; the effect of pretreatment with T3 varied. The presence of alanine in the incubating medium caused a marked increase in oxygen consumption. A seasonal effect was also found. The respiration of isolated toad bladder was stimulated by a wide range of concentrations of thyroxine in vitro, and there were two peaks of stimulation.

scholarly journals A randomised, double- blind, cross-over study investigating the prebiotic effect of agave fructans in healthy human subjects

2015 ◽  
Vol 4 ◽  
Author(s):  
P. Ramnani ◽  
A. Costabile ◽  
A. G. R. Bustillo ◽  
G. R. Gibson
Keyword(s):  
Denaturing Gradient Gel Electrophoresis ◽  
Human Subjects ◽  
Secretory Iga ◽  
Healthy Human ◽  
Double Blind ◽  
Bacterial Populations ◽  
Healthy Human Subjects ◽  
Gradient Gel Electrophoresis

AbstractThis placebo-controlled, randomised, double-blind, cross-over human feeding study aimed to determine the prebiotic effect of agave fructans. A total of thirty-eight volunteers completed this trial. The treatment consisted of 3 weeks' supplementation with 5 g/d of prebiotic agave fructan (Predilife) or equivalent placebo (maltodextrin), followed by a 2-week washout period following which subjects were crossed over to alternate the treatment arm for 3 weeks followed by a 2-week washout. Faecal samples were collected at baseline, on the last day of treatment (days 22 and 58) and washout (days 36 and 72), respectively. Changes in faecal bacterial populations, SCFA and secretory IgA were assessed using fluorescentin situhybridisation, GC and ELISA, respectively. Bowel movements, stool consistencies, abdominal comfort and mood changes were evaluated by a recorded daily questionnaire. In parallel, the effect of agave fructans on different regions of the colon using a three-stage continuous culture simulator was studied. Predilife significantly increased faecal bifidobacteria (log109·6 (sd0·4)) and lactobacilli (log107·7 (sd0·8)) compared with placebo (log109·2 (sd0·4);P = 0·00) (log107·4 (sd0·7);P= 0·000), respectively. No change was observed for other bacterial groups tested, SCFA, secretory IgA, and PGE2concentrations between the treatment and placebo. Denaturing gradient gel electrophoresis analysis indicated that bacterial communities were randomly dispersed and no significant differences were observed between Predilife and placebo treatments. Thein vitromodels showed similar increases in bifidobacterial and lactobacilli populations to that observed with thein vivotrial. To conclude, agave fructans are well tolerated in healthy human subjects and increased bifidobacteria and lactobacilli numbersin vitroandin vivobut did not influence other products of fermentation.

scholarly journals METABOLIC EFFECTS OF LATHYROGENIC AGENTS ON CARTILAGE IN VIVO AND IN VITRO

1961 ◽  
Vol 113 (2) ◽  
pp. 381-403 ◽  
Author(s):  
Morris J. Karnovsky ◽  
Manfred L. Karnovsky
Keyword(s):  
Chondroitin Sulfate ◽  
Costal Cartilage ◽  
Epiphyseal Cartilage ◽  
Metabolic Effects ◽  
In Vitro System ◽  
Low Concentrations ◽  
Biochemical Indices ◽  
Hexosamine Content

The effects of lathyrogenic agents in vivo and in vitro are described, in respect to some biochemical indices of cartilage metabolism. Lathyrogenic agents in vivo inhibited the incorporation of radiosulfate into rat epiphyseal cartilage and the isolated chondroitin sulfate. No significant changes in hydroxyproline or hexosamine content of epiphyseal cartilage were found, but there was a marked increase in water content. The content of chondroitin sulfate, measured as uronic acid, was decreased. The importance of taking growth rate differences between control and experimental rats into account in assessing the effects of lathyrogenic agents in vivo is emphasized. In an in vitro system, utilizing fresh calf costal cartilage slices, the presence of low concentrations of lathyrogenic agents markedly affected various metabolic events. The incorporation into cartilage slices of sulfate-S35, glucose-U-C14, and glycine-1-C14 was significantly depressed, as was the production of organic acids, including lactic acid. In general, these effects were more severe under anaerobic conditions. Glutamine restored the activities of the slices treated with lathyrogenic agents to control values obtained in the absence of either lathyrogen or glutamine.

Thrombin induces Contraction And increased 51-Cr Release from Cultured Human Endothelial Cells

1979 ◽  
Author(s):  
K.S. Galdal ◽  
S.A. Evensen
Keyword(s):  
Endothelial Cells ◽  
Calf Serum ◽  
Linear Increase ◽  
Foetal Calf Serum ◽  
Human Endothelial Cells ◽  
Trypan Blue Exclusion ◽  
Trypan Blue Exclusion Test ◽  
Release Assay

Injury to human endothelial cells(EC) in primary culture was evaluated by a 51-Cr release assay, phase contrast microscopy and the trypan blue exclusion test. Normal integrity of EC, was maintained and 51-Cr release showed a slow linear increase during 24h incubation with either RPMI 1640 supplemented with 20% foetal calf serum, glutamine and antibiotics(SCM) or normal human serum(NHS). Thrombin in a concentration as low as 0.1 IU/ml induced obvious contraction of EC incubated in SCM, but the cells remained fixed to the bottom of the wells. Cell contraction was maximal after 15min and disappeared within 4h. 51-Cr release increased 2-3 fold within a few minutes and remained increased during an incubation period of 4h. The injurious effect of thrombin was inhibited in SCM containing hirudin(l.7 u/ml) or in NHS. ADP(10-5 M), endotoxin (0.1mg/ml) and 5 vasoactive agents adrenalin 5.5 10-5, noradrenalin 5.9 10-5 M, histamine 9.10-4 M, bradykinin 7.5 10-7 M and serotonin 10-5 M) did not cause cellular injury. Cultured human EC are injured by thrombin. The other tested agents do not appear to induce direct injury in vitro, but may interact with cellular elements in the blood to produce the endothelial injury previously observed in vivo.

The assessment of zinc status of an animal from the uptake of65Zn by the cells of whole blood in vitro

1978 ◽  
Vol 39 (2) ◽  
pp. 297-306 ◽  
Author(s):  
J. K. Chesters ◽  
Marie Will
Keyword(s):  
Alkaline Phosphatase ◽  
Whole Blood ◽  
Surgical Stress ◽  
Zn Deficiency ◽  
Zn Uptake ◽  
Zn Concentration ◽  
Plasma Alkaline Phosphatase ◽  
Zn Status ◽  
Dietary Deficiency

1.65Zn uptake by blood cells in vitro has been compared with plasma Zn concentration and plasma alkaline phosphatase (EC3.1.3.1) activity as indicators of an animal's Zn status.2. Dietary Zn deficiency, low food intake, reduced dietary protein content and endotoxin administration all reduced plasma Zn concentration in the rat. In each case there was a parallel reduction in plasma alkaline phosphatase activity and an increase in65Zn uptake in vitro by cells of whole blood.3. A similar relationship between the three measurements existed in sheep with lowered plasma Zn concentrations whether these were caused by dietary deficiency or by post-surgical stress.4.65Zn uptake by cells of whole blood did not differentiate dietary Zn deficiency from the other factors which reduce plasma Zn under ‘field’ conditions.5.65Zn uptake by the cells in whole blood in vitro was three to five times less rapid in blood of ruminant origin than in that from non-ruminants. This difference related to the erythrocytes rather than to the leukocytes or the plasma.

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