34 research outputs found
DISORDERS OF THE DIGESTIVE-SYSTEM IN THE ELDERLY
CHANGES in the anatomy and physiology of the epithelium of the digestive organs because of aging are slight.1 The functional capacity of both the secretory and absorptive cells of the gut is so great that a decrease to as little as 5 to 10 percent of normal function is required for a clinical effect to be evident. In contrast to the epithelial-cell reserve, connective-tissue changes are manifested in midlife, and age-related changes in these tissues are responsible for many digestive disorders, such as colonic vascular ectasias and diverticula of the gut.
The anatomical and physiologic changes that do occur in the elderly may be due to the vicissitudes of life (intercurrent disease or the effects of the environment, nutrition, alcohol, tobacco, or other drugs) or to specific disease rather than to aging alone. The decreased effectiveness of the immune system in the elderly2 may influence the course of diseases of the gastrointestinal tract. The number of antibodies to foreign antigens decreases with aging, whereas the number of autoantibodies increases.3 Alterations in T-cell function occur more frequently than changes in B-cell function in the elderly.3 Little is known about how such immunologic changes affect the course of specific diseases of the digestive system.
The polypharmacy that is common among the elderly4 complicates the evaluation and treatment of digestive disorders in these patients. The indiscriminate and inappropriate use of medications to treat gastrointestinal disorders should be avoided in order to prevent some of the adverse reactions, such as delirium from cimetidine, constipation from iron supplements and aluminum-containing antacids, and diarrhea from magnesium-containing antacids and prostaglandin analogues.4 , 5
This review will consider some of the age-related changes of the digestive organs and some of the diseases to which the elderly are particularly vulnerable. Neoplasms will not be discussed
Cell-free, high-density lipoprotein-specific phospholipid efflux assay predicts incident cardiovascular disease
BACKGROUND. Cellular cholesterol efflux capacity (CEC) is a better predictor of cardiovascular disease (CVD) events than HDLcholesterol (HDL-C) but is not suitable as a routine clinical assay.METHODS. We developed an HDL-specific phospholipid efflux (HDL-SPE) assay to assess HDL functionality based on whole plasma HDL apolipoprotein-mediated solubilization of fluorescent phosphatidylethanolamine from artificial lipid donor particles. We first assessed the association of HDL-SPE with prevalent coronary artery disease (CAD): study I included NIH severe-CAD (n = 50) and non-CAD (n = 50) participants, who were frequency matched for sex, BMI, type 2 diabetes mellitus, and smoking; study II included Japanese CAD (n = 70) and non-CAD (n = 154) participants. We also examined the association of HDL-SPE with incident CVD events in the Prevention of Renal and Vascular End-stage Disease (PREVEND) study comparing 340 patients with 340 controls individually matched for age, sex, smoking, and HDL-C levels.RESULTS. Receiver operating characteristic curves revealed stronger associations of HDL-SPE with prevalent CAD. The AUCs in study I were as follows: HDL-SPE, 0.68; apolipoprotein A-I (apoA-I), 0.62; HDL-C, 0.63; and CEC, 0.52. The AUCs in study II were as follows: HDL-SPE, 0.83; apoA-I, 0.64; and HDL-C, 0.53. Also longitudinally, HDL-SPE was significantly associated with incident CVD events independent of traditional risk factors with ORs below 0.2 per SD increment in the PREVEND study (P < 0.001).CONCLUSION. HDL-SPE could serve as a routine clinical assay for improving CVD risk assessment and drug discovery.</p
Cell-free, high-density lipoprotein-specific phospholipid efflux assay predicts incident cardiovascular disease
BACKGROUND. Cellular cholesterol efflux capacity (CEC) is a better predictor of cardiovascular disease (CVD) events than HDLcholesterol (HDL-C) but is not suitable as a routine clinical assay.METHODS. We developed an HDL-specific phospholipid efflux (HDL-SPE) assay to assess HDL functionality based on whole plasma HDL apolipoprotein-mediated solubilization of fluorescent phosphatidylethanolamine from artificial lipid donor particles. We first assessed the association of HDL-SPE with prevalent coronary artery disease (CAD): study I included NIH severe-CAD (n = 50) and non-CAD (n = 50) participants, who were frequency matched for sex, BMI, type 2 diabetes mellitus, and smoking; study II included Japanese CAD (n = 70) and non-CAD (n = 154) participants. We also examined the association of HDL-SPE with incident CVD events in the Prevention of Renal and Vascular End-stage Disease (PREVEND) study comparing 340 patients with 340 controls individually matched for age, sex, smoking, and HDL-C levels.RESULTS. Receiver operating characteristic curves revealed stronger associations of HDL-SPE with prevalent CAD. The AUCs in study I were as follows: HDL-SPE, 0.68; apolipoprotein A-I (apoA-I), 0.62; HDL-C, 0.63; and CEC, 0.52. The AUCs in study II were as follows: HDL-SPE, 0.83; apoA-I, 0.64; and HDL-C, 0.53. Also longitudinally, HDL-SPE was significantly associated with incident CVD events independent of traditional risk factors with ORs below 0.2 per SD increment in the PREVEND study (P < 0.001).CONCLUSION. HDL-SPE could serve as a routine clinical assay for improving CVD risk assessment and drug discovery.</p
Erratum: Corrigendum: MicroRNAs are transported in plasma and delivered to recipient cells by high-density lipoproteins
A Simple Fluorescent Cholesterol Labeling Method to Cryoprotect and Detect Plasma Lipoprotein-X
Lipoprotein-X (LpX) are abnormal nephrotoxic lipoprotein particles enriched in free cholesterol and phospholipids. LpX with distinctive lipid compositions are formed in patients afflicted with either familial LCAT deficiency (FLD) or biliary cholestasis. LpX is difficult to detect by standard lipid stains due to the absence of a neutral lipid core and because it is unstable upon storage, particularly when frozen. We have recently reported that free cholesterol-specific filipin staining after agarose gel electrophoresis sensitively detects LpX in fresh human plasma. Herein, we describe an even more simplified qualitative method to detect LpX in both fresh and frozen–thawed human FLD or cholestatic plasma. Fluorescent cholesterol complexed to fatty-acid-free BSA was used to label LpX and was added together with trehalose in order to cryopreserve plasma LpX. The fluorescent cholesterol bound to LpX was observed with high sensitivity after separation from other lipoproteins by agarose gel electrophoresis. This methodology can be readily developed into a simple assay for the clinical diagnosis of FLD and biliary liver disease and to monitor the efficacy of treatments intended to reduce plasma LpX in these disease states
Safety and Tolerability of ACP-501, a Recombinant Human Lecithin:Cholesterol Acyltransferase, in a Phase 1 Single-Dose Escalation Study
Accelerated atherosclerosis and elevated lipoprotein (a) after liver transplantation
Cumulative evidence suggests that lipoprotein(a) [Lp(a)] exerts an independent effect on the initiation and progression of atherosclerotic cardiovascular disease. The genetically mediated expression of apolipoprotein(a), which is the key structural and functional component of Lp(a), occurs in hepatocytes with subsequent extracellular Lp(a) assembly at the hepatic cell surface. Here, we describe a case of elevated Lp(a) concentrations identified after (and likely acquired by) orthotopic liver transplantation that contributed to accelerated atherosclerotic cardiovascular disease despite intensive therapeutic interventions. This case study represents an important example to include Lp(a) screening in routine lipid panel testing for all liver transplant donors and recipients; to reduce unanticipated and debilitating cardiovascular morbidity and mortality
Cardiometabolic risk factors and health behaviors in family caregivers.
The purpose of this study was to compare components of cardiometabolic risk and health behaviors of 20 family caregivers of allogeneic hematopoietic stem cell transplant patients to those of age, gender, and race/ethnicity-matched controls. A prospective, repeated measures design was used to compare cardiometabolic risk and health behaviors in caregivers and controls at three time-points: pre-transplantation, discharge, and six weeks post-discharge. Measures included components of metabolic syndrome, Reynolds Risk Score, NMR serum lipoprotein particle analyses, and the Health-Promoting Lifestyle Profile II (HPLP-II). Mixed-model repeated measure analyses were used. There were no between or within group differences in LDL cholesterol, HDL cholesterol, and triglycerides. There was a significant interaction effect between time and role in large VLDL concentration (VLDL-P) (F (2, 76) = 4.36, p = .016), with the trajectory of large VLDL-P increasing over time in caregivers while remaining stable in controls. Within caregivers, VLDL particle size (VLDL-Z) was significantly larger at time-point three compared to time-points one (p = .015) and two (p = .048), and VLDL-Z was significantly larger in caregivers than in controls at time point three (p = .012). HPLP-II scores were lower in caregivers than controls at all time-points (p < .01). These findings suggest that caregiving may have a bigger impact on triglycerides than on other lipids, and it is through this pathway that caregivers may be at increased cardiometabolic risk. More sensitive measurement methods, such as NMR lipoprotein particle analyses, may be able to detect early changes in cardiometabolic risk