The susceptibility of the moderate halophile Vibrio costicola to heavy metals

Fifty-eight strains of the moderate halophile Vibrio costicola , including both culture collection strains and freshly isolated strains from solar salterns, were examined for their susceptibility to 10 heavy metal ions by using an agar dilution technique. All strains were sensitive to cadmium, copper, silver, zinc and mercury. This latter ion showed the highest activity even at 0·05 mmol/1 metal concentration. On the other hand, all strains were similarly tolerant to lead, and a great proportion of them were also tolerant to nickel (91%) and chromium (88%). Only 44% and 14% of them showed tolerance to arsenate and cobalt, respectively. The majority of strains (96·4%) were multiply metal-tolerant, with three different metal ion tolerances as the major pattern.     

Functional architecture of the ligamentum arteriosum in adults]

The ligamentum arteriosum was studied in eight normal adult human hearts obtained at autopsy. Four of these hearts were treated by the Zemper method and extensively dissected under a steromicroscope (from X 6 up to X 40); two were embedded in celloidin and sectioned at 100mugm; two were embedded in paraffin and sectioned one 50mugm and the other at 75 mugm. Section were stained by the axan and the resorcin-fuchsin methods. Unstained sections were examined under polarized light.The ligamentum arteriosum may be considered as a small smooth muscle, whose origin is in the arteria pulmonalis sinistra and the insertion in the arcus aortae. Therefore, the ligamentum arterisum may be considered as a myoelastic system, included in a collagenous stroma. Muscle, elastic and collagen fibers present a cross-spiral disposition. Being a myoelastic system with a collagen component, the ligamentum arteriosum cannot be considered as a simple arcus aortae support; it must play some functional role in controlling the arcus aortae curvature during the several different steps of the cardiac cycle.     

Elastase in the different primary granules of the human neutrophil

Elastase in the human neutrophil is associated with various subpopulations of primary granules of different density. The proportion of this enzyme that is extracted with acetate pH 4.2 and cetyltrimethylammonium bromide varies in the different subpopulations. Nevertheless, the electrophoretic mobility and relative proportions of elastase isoenzymes is the same in both extracts from the different subpopulations. On stimulation of neutrophils with N-formylmethionylleucylphenylalanine, elastase is not released from the least dense subpopulation, whereas other two subpopulations do undergo degranulation to approximately the same extent. However, the release of elastase from these two denser granules differs after they are isolated and treated with calcium.     

Obesity in Older Adults: Technical Review and Position Statement of the American Society for Nutrition and NAASO,The Obesity Society

Obesity causes serious medical complications and impairs quality of life. Moreover, in older persons, obesity can exacerbate the age‐related decline in physical function and lead to frailty. However, appropriate treatment for obesity in older persons is controversial because of the reduction in relative health risks associated with increasing body mass index and the concern that weight loss could have potential harmful effects in the older population. This joint position statement from the American Society for Nutrition and NAASO, The Obesity Society reviews the clinical issues related to obesity in older persons and provides health professionals with appropriate weight‐management guidelines for obese older patients. The current data show that weight‐loss therapy improves physical function, quality of life, and the medical complications associated with obesity in older persons. Therefore, weight‐loss therapy that minimizes muscle and bone losses is recommended for older persons who are obese and who have functional impairments or medical complications that can benefit from weight loss.     

The binding of folyl polyglutamates by hemoglobin

Pteroyl polyglutamates bind to hemoglobin with an affinity which leaves only a minor fraction of red cell folate in the free state. This could serve as a regulating mechanism for protein synthesis in the differentiating erythroblast.     

EVIDENCE FOR A MOSAIC HYBRID ZONE IN THE GRASS SHRIMP PALAEMONETES KADIAKENSIS (PALAEMONIDAE) AS REVEALED BY MULTIPLE GENETIC MARKERS

Molecular techniques provide powerful tools for studying the geographic structure of hybrid zones and the dynamics of gene exchange between incipient species. We examined allozyme variation at five loci (PGM, GPI, MDH-1, MDH-2, and LDH) for 27 populations of Palaemonetes kadiakensis from the central, coastal, and eastern regions of Texas. Central Texas populations of P. kadiakensis exhibited highly significant linkage disequilibrium and departures from Hardy-Weinberg genotype proportions. In populations with linkage disequilibrium, allelic differences at GPI defined two types of P. kadiakensis, designated A and B. Both types existed in central Texas with little or no evidence of interbreeding, whereas the populations from all other localities showed complete introgression of type B alleles into the type A gene pool. We also examined ribosomal DNA (rDNA) and mitochondrial DNA (mtDNA) variation in a subset of populations, chosen to cover a range of geographic locations and levels of linkage disequilibrium. Two groups of mtDNA haplotypes and two restriction fragment patterns for the rDNA corresponded to allozyme type A and B individuals in populations exhibiting linkage disequilibrium. In populations with ongoing hybridization, all hybrid animals (N= 15) exhibited type A mtDNA. Exhibition of type A mtDNA indicated that type A females had mated successfully with type B males, but type B females had not mated successfully with type A males. Genotype distributions suggest reduced reproduction by hybrid offspring in central Texas populations. These patterns are consistent with a mosaic model of hybrid zone dynamics.     

Short- and long-term effects of proallatotoxin (ethoxyprecocene II) on Rhodnius prolixus females

Oogenesis and oviposition can be inhibited in female of Rhodnius prolixus by means of short-term experiment (first reproductive cycle) of a single dose of ethoxyprecocene II given by ingestion. The inhibition is dose-dependent as measured by oocyte growth, egg maturation and egg deposition. In a long-term experiment (second and third reproductive cycles) egg production and oogenesis can be partially or totally re-established by subsequent blood meals without ethoxyprecocene II. These findings suggest that in female R. prolixus, damage caused to corpus allatum by ethoxyprecocene II, in certain cases, is not irreversible.     

Specific binding of atrial natriuretic factor to renal glomeruli in Doca- and Doca-salt-treated rats correlation with atrial and plasma levels

Since volume expansion and high blood pressure (BP) are known stimuli of atrial natriuretic factor (ANF) release, and since this peptide may be involved in mineralocorticoid escape, we investigated the effects of chronic deoxycorticosterone (DOCA) and DOCA-NaC1 treatment on renal glomerular ANF receptor density and affinity in relation to atrial and plasma ANF levels. An increase in plasma immunoreactive ANF (IR-ANF) was observed both after two and four weeks of treatment. IR-ANF concentrations were elevated in the left atrium only in four-week DOCA treated rats. Administration of the mineralocorticoid alone resulted in a decreased density of glomerular ANF receptors in both time periods investigated. DOCA-NaC1-treated animals presented an increased receptor density during the pre-hypertensive stage (2 weeks) and a reduced density in the later hypertensive period (4 weeks). Receptor affinity in both groups was identical to that in the controls after 2 weeks and was augmented after 4 weeks of treatment. Our data suggest that the down-regulation of renal glomerular ANF receptors during chronic DOCA-NaC1 administration may play a role in the maintenance of high BP in this model of volume-expanded hypertension.