Objective and subjective rapid frailty screening tools in people with HIV.

OBJECTIVES: As people with HIV (PWH) age, the prevalence of frailty increases. Rapid screening tests to identify frailty within HIV outpatient settings are required to identify at-risk individuals. We undertook a service evaluation to assess three short frailty assessments in PWH. METHODS: We assessed two objective [gait speed (GS), timed-up-and-go test (TUGT)] and one subjective [the self-reported health questionnaire (SRH)] frailty screening tools in PWH aged > 40 years attending a single HIV outpatient department. Factors associated with positive frailty screening tests (defined as GS < 0.8 m/s, TUGT ≥ 10 s and SRH score < 6) were assessed using logistic regression models. ETHICAL CONSIDERATIONS: This was a service evaluation and was approved as a service evaluation by the Imperial College Healthcare NHS trust HIV clinical research committee (February 2020). All participants were given verbal information and were able to terminate the screening tests at any time. RESULTS: Of 84 PWH approached, 80 individuals completed all screening tests (median age = 56 years, range: 40-80) with a positive frailty screening prevalence in 19%, 33% and 20% for GS, TUGT and SRH, respectively. All tests were considered acceptable to participants. Factors statistically significantly associated with frailty included age (GS and TUGT), detectable HIV RNA (TUGT), number of comorbidities (GS and TUGT), presence of polypharmacy (GS and TUGT) and total number of concomitant medication (GS and SRH). CONCLUSIONS: Rates of positive screening tests for frailty are dependent on screening tool used, with all three tools being acceptable to participants. Objective measures of frailty screening (GS and TUGT) are more closely associated with clinical parameters than is a subjective measure of frailty screening (SRH).

Effect of dietary vitamin E on rumen biohydrogenation pathways and milk fat depression in dairy cows fed high-fat diets.

Six lactating Holstein cows were assigned to a replicated Latin square design to test the effect of dietary vitamin E on milk fat depression and on the increased production of milk trans-10 C18:1 classically observed when feeding high doses of unsaturated fatty acids with low-fiber diets. Two diets (linseed diet and linseed diet + 12,000 IU of vitamin E/d) were compared during 2 periods of 21 d. The linseed diet presented a forage-to-concentrate ratio of 50:50 and contained extruded linseed (1.86 kg/d) and linseed oil (190 g/d). It was conceived to favor the "trans-11 to trans-10 shift" (low structural value and high level of unsaturated fatty acids). Milk yield and protein content were not affected by the diets. Milk of cows fed the linseed diet presented the typical symptoms of milk fat depression associated with a shift in biohydrogenation pathways: low fat content and high level of trans-10 C18:1. However, the high dose of dietary vitamin E provided significantly increased milk fat content (by 17.93%) and yield (by 15.56%) and decreased trans-10 C18:1 content (by 47.06%). In addition, it managed to significantly increase the daily yields of vaccenic (by 102.56%) and rumenic acids (by 56.67%). However, the sequence of administration of vitamin E influenced its effect, as vitamin E seemed to be more active in limiting the "trans-11 to trans-10 shift" when it was incorporated in the diet simultaneously with the fat. Once the shift had occurred, the subsequent addition of vitamin E was no longer able to completely counteract this process.

The in vitro manipulation of carbohydrate metabolism: a new strategy for deciphering the cellular defence mechanisms against nitric oxide attack.

This study was aimed at examining the effects of manipulating the carbohydrate source of the culture medium on the cellular sensitivity of epithelial cells to an oxidative attack. Our rationale was that substituting galactose for glucose in culture media would remove the protection afforded by glucose utilization in two major metabolic pathways, i.e. anaerobic glycolysis and/or the pentose phosphate pathway (PPP), which builds up cellular reducing power. Indeed, we show that the polarized human colonic epithelial cell line HT29-Cl.16E was sensitive to the deleterious effects of the NO donor PAPANONOate [3-(2-hydroxy-2-nitroso-1-propylhydrazino)-1-propanamine] only in galactose-containing medium. In such medium NO attack led to cytotoxic and apoptotic cell death, associated with formation of derivatives of NO auto-oxidation (collectively termed NOx) and peroxynitrite, leading to intracellular GSH depletion and nitrotyrosine formation. The addition of 2-deoxyglucose, a non-glycolytic substrate, to galactose-fed cells protected HT29-Cl. 16E cells from NO attack and maintained control GSH levels through its metabolic utilization in the PPP, as shown by (14)CO(2) production from 2-deoxy[1-(14)C]glucose. Therefore, increasing the availability of reducing equivalents without interfering with energy metabolism is able to prevent NO-induced cell injury. Finally, this background provides the conceptual framework for establishing nutritional manipulation of cellular metabolic pathways that could provide new means for (i) deciphering the mechanisms of cell injury by reactive nitrogen species and reactive oxygen species at the whole-cell level and (ii) establishing the hierarchy of intracellular defence mechanisms against these attacks.

Multilayer film elements for clinical analysis: general concepts.

Dry, thin films containing all necessary reagents for clinical analysis by colorimetry have been designed. Reagents in a matrix of hydrophilic polymer are coated on top of a transparent plastic base. A white isotropically porous polymer spreading layer, 80% void volume, is coated over the reagent layer(s). In the analysis, a drop (typically 10 microliter) of undiluted serum or other fluid is touched to the spreading layer. The fluid spreads rapidly and uniformly through the pore structure, filling a void volume corresponding to the drop volume. Water and low-molecular-weight components diffuse from the spreading layer into the reagent layer(s), initiating the reaction sequence. The spreading layer acts also as a white optical diffuser for reflection densitometry. Optical reflection density is linearized through use of the function developed by Williams and Clapper [J. Opt. Soc. Am. 43, 595 (1953)] to convert reflection to transmission density. A wide variety of chemical assays are compatible with this format. As an example, for the glucose film we found coefficients of variation of 1.5% in predicting glucose concentrations in control sera during 20 days. Results for glucose concentrations in several hundred patients' sera by the present method were very cose to those obtained with the Center for Disease Control's hexokinase reference method.