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.     

Proteoglycan metabolism associated with mouse metanephric development: morphologic and biochemical effects of beta-D-xyloside

Morphology and de novo incorporation of [35S]sulfate into proteoglycans were studied in fetal mouse kidneys at the onset of organogenesis. Branching morphogenesis and nephron development in organ culture and in vivo were associated with de novo synthesis of chondroitin-SO4 and heparan-SO4 proteoglycans. The role of proteoglycan metabolism in metanephrogenesis was then studied by analysis of the effects of p-nitrophenyl-beta-D-xylopyranoside (beta-D-xyloside) on renal development and proteoglycan metabolism. Incubation of fetal kidneys in beta-D-xyloside at concentrations of 1.0 and 0.5 mM, but not at 0.1 mM, caused inhibition of ureteric branching and markedly diminished synthesis of a large Mr 2.0 X 10(6) Da chondroitin-SO4 proteoglycan. Incorporation of [35S]sulfate was stimulated at all beta-D-xyloside concentrations, reflecting synthesis of xyloside initiated dermatan-35SO4 chains. In contrast to dramatic effects on chondroitin-SO4 synthesis and ureteric branching, beta-D-xyloside had no effect on heparan-SO4 synthesis or on development of the glomerulus and glomerular basement membrane. We thus characterize the proteoglycans synthesized early in the course of renal organogenesis and describe observations which suggest an association between metabolism of chondroitin-SO4 proteoglycan and development of the ureter.     

Phosphatidylinositol Phosphodiesterase (Phospholipase C) Activity in the Pineal Gland: Characterization and Photoneural Regulation

Phosphatidylinositol phosphodiesterase (PL-C) appears to be a key element in the adrenergic regulation of pineal cyclic AMP levels. In the present study, the rat pineal enzyme was characterized using exogenous [3H]phosphatidylinositol (0.5 mM) as substrate. Half the enzyme activity was found in the cytosolic fraction, but the highest specific concentration was associated with the membrane fraction. Two pH optima (5.5 and 7.5) of enzyme activity were observed for the membrane fraction but only one in the cytosol fraction (pH 5.5). Enzyme activity in both fractions was Ca2+ dependent. In the case of the membrane protein in pH 7.5, the enzyme activity was sensitive to changes in Ca2+ in the 10-100 nM range. Addition of an equimolar concentration of phosphatidylinositol 4-phosphate nearly completely inhibited the hydrolysis of [3H]phosphatidylinositol; other phospholipids (1.0 mM) were less potent. This may reflect our present finding that [3H]phosphatidylinositol 4-phosphate is a better substrate than [3H]phosphatidylinositol for the enzyme. Stimulus deprivation (2 weeks of constant light or superior cervical ganglionectomy) reduced the cytosolic activity by 30% and had no effect on the membrane-associated enzyme.     

Ecology of muskoxen in Jameson Land, northeast Greenland

Muskoxen Ovibos moschatus in Jameson Land exist at a density of somewhat more than 1 km⁻² of useable habitat and select moist meadows and snow bed vegetation for summer grazing and wind-exposed, dry dwarf shrub heath vegetation in winter. Graminoids dominate the winter diet and willows are the main component of the summer diet. Quality of the winter diet, as measured by the protein to fiber ratio is about one fourth that of the summer diet. During summer muskoxen supplement dietary sodium by using mineral licks. Muskoxen, especially females, retain considerable unused fat reserves through the winter and these are drawn upon during the post-calving period of lactation. Alternate year breeding is a common occurrence. Calves are frequently not weaned before the end of their first winter. Mean calf mortality is relatively low in the absence of significant predation and annual removal by hunting Inuits approaches the annual increment.     

Ethanol inhibits dual receptor stimulation of pineal cAMP and cGMP by vasoactive intestinal peptide and phenylephrine

Concurrent activation of vasoactive intestinal peptide and alpha 1-adrenergic receptor resulted in greater than 20-fold increases in pineal cAMP and cGMP accumulation. We now find that an intoxicating level of ethanol (0.2%, 34 mM) inhibits greater than 50% the large increases in pineal cAMP and cGMP produced by concurrent treatment with vasoactive intestinal peptide and phenylephrine. The potency of the various alcohols tested was directly related to their chain length. This inhibition appears to be specific since a five-fold higher concentration of ethanol does not inhibit the stimulation of cAMP and cGMP accumulation produced by concurrent treatment with isoproterenol and phenylephrine. Accordingly, it seems that one mechanism of action of ethanol on neural function may be its ability to selectively inhibit ethanol-sensitive integrative mechanisms which regulate cyclic nucleotides.     

The rat MIS1/Pvt-1 locus is syntenic with MYC on chromosome 7

Mouse Pvt-1 and rat MIS1 are frequent proviral integration sites in retrovirally induced lymphomas. The Pvt-1 locus is also involved in mouse plasmacytoma (6;15) and in the variant Burkitt lymphoma (2;8) translocations. We show that the Pvt-1/MIS1 locus is syntenic with MYC on rat chromosome 7. This is consistent with a postulate of close linkage and, possibly, a functional relationship between the MYC protooncogene and the MIS1/Pvt-1 locus.     

Metallothionein induction by nonsteroidal antiinflammatory drugs

In the present study we report on the effects of commonly used nonsteroidal antiinflammatory drugs on metallothionein (MT) and MT-I mRNA levels. A single dose of chloroquine (100 mg/kg), diclofenac (100 mg/kg), indomethacin (10 mg/kg), or piroxicam (100 mg/kg) was administered ip to C57B1 mice. After 18 h, MT levels were determined with a Cd-saturation radioassay. MT-I mRNA levels were measured by Northern Blot analyses using a probe containing the mouse MT-I gene. All drugs tested caused an increase in the MT content of the liver but not of the kidneys and lung. The lowest and highest effects were observed with chloroquine (8 times the control value) and diclofenac (18 times), respectively. In accordance with the stimulation of MT synthesis, increased accumulation of hepatic MT-I mRNA could be demonstrated. These results indicate that elevated MT levels may contribute to the effectiveness of nonsteroidal antiinflammatory drugs in the treatment of rheumatoid arthritis (RA).     

Anchorage-independent growth of RSV-transformed rat (GCA, W 12 and XC) cells

Three RSV-transformed rat cell lines: GCA, W12 and XC were characterized as to their ability to anchorage-independent growth in comparison to normal rat kidney (NRK-49F) cells. Differences in the threshold density (TD) and colony forming efficiency (CFE) of the investigated cells are described. The ability of virally transformed cells to stimulation of soft agar colony formation of NRK cells in coculture assay was presented. The production of TGFs-like factors by GCA, W12 and XC cells was suggested.     

Continuous microbial desulfurization of coal--application of a multistage slurry reactor and analysis of the interactions of microbial and chemical kinetics

Microbial desulfurization of coal by pyrite oxidizing bacterial enrichment cultures has been studied in air-agitated slurry reactors of 4- and 20-L volumes. Batch experiments showed that inoculation with an active bacterial culture is essential to minimize the lag phase, although a considerable number of pyrite oxidizing bacteria was found on the coal prior to desulfurization. For detailed investigations of kinetics, energy requirements, and technical applicability, a bioreactor equipment consisting of a cascade of eight stages was developed and operated continuously. Microbial desulfurization of coal-monitored by measuring the axial profile of dissolved iron concentration, real and maximum oxygen consumption rates, and cell concentration-at pulp densities to 30% was performed over a period of 200 days without any disturbances concerning the aeration system, fluidization, transport of solids and microbial growth. At a pulp density of 20%, a pyrite conversion of 68% was achieved after the third reactor stage at a total residence time of five days in the first three stages. The kinetics of pyrite degradation were found to be well described by a rate equation of first order in pyrite surface area concentration if the pyrite is directly accessible for microbial attack. Rate constants were determined to 0.48 mg pyrite/(cm(2) day) in the first and to 0.24 mg pyrite/(cm(2) day) in the following reactor stages. Kinetic models taking into account adsorption/desorption as well as growth kinetics failed to describe the observed reaction rates. However, a model treating pyrite degradation and microbial growth kinetics formalistically seems to be applicable when backmixing between the reactor stages can be avoided. The advantage of a multistage reactor in comparison to single-stage equipment was shown by calculation. To obtain a pyrite conversion of 68%, a three-stage reactor would require only 58% of the volume of single-stage equipment.Measurement of oxygen consumption rates proved to provide quickly and easily measurable parameters to observe microbial coal desulfurization in technical scale: the real oxygen consumption rate is correlated to the pyrite oxidation rate and the maximum oxygen consumption rate is correlated to the concentration of viable cells. The Y(o/s) coefficient for the amount of oxygen consumed per mass unit of pyrite oxygen was determined to approximately 0.33 in comparison to 1.0 which can be calculated from stoichiornetry. This could yet not be explained. Chemical leaching experiments as well as sulfur analyses of desulfurized coal samples showed that the microorganisms play the main role in degradation of pyrite from coal and that pyrite oxidation by ferric iron can be neglected.