Biomedical subjects

J Preisser

Publications and source records attributed to J Preisser.

10 recordsLinked to original sources

PubMed2000

The rapidity of drug dose escalation influences blood pressure response and adverse effects burden in patients with hypertension: the Quinapril Titration Interval Management Evaluation (ATIME) Study. ATIME Research Group.

BACKGROUND: Antihypertensive medication doses are typically increased within several weeks after initiation of therapy because of inadequate blood pressure (BP) control and/or adverse effects. METHODS: We conducted a parallel-group clinical trial with 2935 subjects (53% women, n=1547) aged 21 to 75 years, with Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure VI stages 1 to 2 hypertension, recruited from 365 physician practices in the southeastern United States. Participants were randomized either to a fast (every 2 weeks; n=1727) or slow (every 6 weeks; n=1208) drug titration. Therapy with quinapril, an angiotensin-converting enzyme inhibitor, was initiated at 20 mg once daily. The dose was doubled at the next 2 clinic visits until the BP was lower than 140/90 mm Hg or a dose of 80 mg was reached. RESULTS: Pretreatment BP averaged 152/95 mm Hg. Patients with stage 2 hypertension reported more symptoms than those with stage 1. The BP averaged 140/86, 137/84, and 134/83 mm Hg in the slow group compared with 141/88, 137/85, and 135/84 mm Hg in the fast group at the 3 respective clinic visits. The BP control rates to lower than 140/90 mm Hg at the 3 clinic visits were (slow, fast, respectively) 41.3%, 35.7% (P<.001); 54.3%, 51.5% (P=.16); and 68%, 62.3% (P=.02). In the fast group, 10.7% of participants experienced adverse events vs 10.8% in the slow group; however, 21.0% of adverse events in the fast group were "serious" vs only 12% in the slow group. CONCLUSION: Slower dose escalation of the angiotensin-converting enzyme inhibitor quinapril provides higher BP control rates and fewer serious adverse events than more rapid drug dose escalation.

Adult↗

PubMed2000

Specialized dementia programs in residential care settings.

The authors conducted a telephone survey in 7 states to determine the prevalence of residential care specialized dementia programs (RC-SDPs) and to identify a sample of homes (n = 56) for more detailed study. The 56 homes were site visited, and data were gathered on facility administration, therapeutic environment, and characteristics of 259 randomly selected residents. Comparison data from 138 nursing home Special Care Units (NH-SCUs) and 1,340 of their residents were obtained from 4 studies conducted in the same 7 states. RC-SDPs were smaller, provided a more homelike environment, and had a higher proportion of residents paying privately, compared with NH-SCUs. Mean levels of cognitive and physical impairment among residents were higher in NH-SCUs; prevalences of psychotropic medication use and problem behaviors were similar. Among RC facilities, small homes were more homelike, provided fewer structured activities, and charged less than larger facilities. RC-SDPs include 5 types: small, independently operated homes; multiple small homes with joint administration; larger, all-dementia facilities; SDPs operated within larger, exclusively RC facilities; and RC-SDPs in multilevel facilities.

Aged↗

PubMed1999

Communication between older adults and their physicians about urinary incontinence.

BACKGROUND: Urinary incontinence (UI) is a common but undertreated condition in older adults. The study objective was to determine older patients' characteristics related to communication patterns with their physicians about UI. METHODS: Telephone surveys of a sample of patients age 60 and older who visited a primary care provider (PCP) for any reason within the past 2 months were conducted. Participating physicians included general internists and family physicians from 41 primary care practices located in the 17 counties of northwest North Carolina whose 435 incontinent and 711 continent patients completed the surveys. The main outcome measures were patients' frequency and amount of urinary leakage, being asked about incontinence, and initiating a discussion of incontinence if not asked by their PCP. RESULTS: Age and gender were significant independent predictors of incontinence. PCPs were significantly more likely to assess incontinent women than incontinent men (21% vs 10%, p = .053). The older cohorts of older adults were significantly more likely to be symptomatic for UI than their younger counterparts. However, the younger cohorts were more likely to be screened for incontinence by their physicians. CONCLUSIONS: Despite the publication of guidelines on improving the screening and management of UI, the problem remains common and underdetected in older adults. Physicians don't ask and patients don't tell. Interventions are needed to remind physicians to screen high risk patients and to encourage patients with UI to communicate with their physicians.

Age Factors↗

PubMed1998

Comparison of the efficacy of dihydropyridine calcium channel blockers in African American patients with hypertension. ISHIB Investigators Group. International Society on Hypertension in Blacks.

BACKGROUND: Hypertension is a prevalent disease among African Americans, and successful treatment rates are low. Since calcium channel blockers are well-tolerated and efficacious in African Americans, we undertook this study to compare the efficacy, safety, and tolerability of 3 commonly prescribed calcium channel blockers: amlodipine besylate (Norvasc), nifedipine coat core (CC) (Adalat CC), and nifedipine gastrointestinal therapeutic system (GITS) (Procardia XL). METHODS: One hundred ninety-two hypertensive patients across 10 study centers were randomly assigned to double-blind monotherapy with amlodipine besylate (5 mg/d), nifedipine CC (30 mg/d), or nifedipine GITS (30 mg/d) for 8 weeks. Patients not achieving therapeutic response after 4 weeks had their dose doubled for the next 4 weeks. The primary end point was a comparison of the average reduction (week 8 minus baseline) in 24-hour ambulatory diastolic blood pressure (DBP). Secondary end points included a comparison of average 24-hour ambulatory systolic blood pressure (SBP), office SBP or DBP reduction, responder rates, safety, and tolerability. RESULTS: One hundred sixty-three patients were evaluable for efficacy after 8 weeks. There was no significant difference in the average 24-hour ambulatory DBP (-8.5, -9.0, and -6.1 mm Hg, respectively) or SBP (-14.3, -15.7, and -11.8 mm Hg, respectively) reduction. Average office SBP and DBP were reduced to a comparable degree (19-22 mm Hg [P =.50] and 12-14 mm Hg [P =.51], respectively). Responder rates (DBP <90 or reduced by > or = 10 mm Hg) were similar (P = .38). Discontinuation rates and adverse event frequency were distributed similarly across the 3 treatment groups. CONCLUSION: The efficacy, safety, and tolerability of the 3 dihydropyridine calcium channel blockers are equivalent in African Americans with stages 1 and 2 hypertension.

Adult↗

PubMed1998

The quality of life of older adults with urinary incontinence: determining generic and condition-specific predictors.

Urinary incontinence (UI) is an unpleasant problem for many adults. This study determined the importance of demographic, health and incontinence variables for the generic and incontinence-specific quality of life (QoL) of older adults (age > or = 60 years). Telephone surveys of adults reporting at least weekly episodes of UI (n = 435) were conducted as part of a randomized, controlled trial. Logistic regression analyses showed that the predictors of generic and incontinence-specific QoL differed. Life satisfaction, a generic outcome, was predicted by education, the number of days in bed due to health problems, the number of days not feeling well and the amount of urine lost. Generic health was related to education, the number of days sick in the previous 30 days and the number of days health issues restricted activities. The incontinence-specific QoL outcomes were predicted by age, mobility difficulties, the amount of urine lost, the frequency of UI, and the number of daytime and night-time voids. The specific QoL measures provide a different profile of those most affected in this sample than that obtained by the generic measures. The most affected are younger persons with severe urine loss. Older persons may have other conditions impinging on QoL and may have adapted behaviourally and psychologically to urine loss.

Aged↗

PubMed1995

Predictors of fear of falling in dizzy and nondizzy elderly.

Fear of falling may constitute an independent risk factor for disability, leading older people to unnecessarily restrict their activity. Sixty older adults with chronic dizziness and 66 healthy controls were studied to help clarify the interrelationships among demographic factors, psychological status, physical health, and fear of falling. Chronic dizziness was strongly associated with fear of falling; among dizzy patients, nearly half (47%) expressed fear of falling, in comparison with 3% of controls. In participants with dizziness, 3 factors predicted fear of falling: an activity of daily living score, the revised Symptom Checklist 90 Depression (Derogatis, 1983) score, and stability when standing with feet together. These results support the concept that fear of falling is multiply determined and that psychological factors play a major role in influencing the symptoms and responses in many older patients with dizziness.

Accidental Falls↗

PubMed1993

Which primary care patients with dizziness will develop persistent impairment?

OBJECTIVE: To determine which factors identifiable during an office visit for dizziness predict chronic impairment from dizziness 3 months later. DESIGN: A prospective cohort study with 3-month telephone follow-up. SETTING: Nine primary care office practices in North Carolina. SUBJECTS: 117 adults who presented to primary care practices because of dizziness. OUTCOME MEASURES: Our outcome of interest, restriction of daily activities due to dizziness 3 months after the enrollment visit, was characterized using three different but correlated self-reported measures. Independent analytic models tested the relationship between demographic variables, health status, psychological state, and dizziness characteristics at baseline and our three measures of activity restriction due to dizziness. RESULTS: A two-stage logistic regression analysis identified the following baseline characteristics to be independent predictors in one or more models of activity-limiting dizziness at 3 months: dependency in instrumental activities of daily living (odds ratio [OR] = 11.1, P = .002); a high anxiety score (OR = 5.7, P = .003); self-rating of health as fair or poor (OR = 3.2, P = .042); the presence of three or more chronic conditions (OR = 1.9, P = .022); interference from chronic conditions (OR = 1.7, P = .012); dizziness duration of greater than 1 year (OR = 20.9, P < .001); frequent dizziness (OR = 4.3, P = .016); subjective imbalance (OR = 4.7, P = .012); and activity limitation due to dizziness (OR = 11.7, P < .001). CONCLUSION: To estimate the prognosis and clinical significance of dizziness complaints, primary care physicians should take into account not only the characteristics of the patient's dizziness but also the patient's baseline health status and psychological state.

Activities of Daily Living↗

PubMed1988

Analysis of the reaction products from incubation of sugarcane vacuoles with uridine-diphosphate-glucose: no evidence for the group translocator.

Isolated sugarcane (Saccharum spp. hybrid H50-7209) vacuoles incorporate radioactivity during incubation with labeled UDP-glucose by a mechanism which was postulated to be responsible for sucrose storage in the vacuoles (UDP-glucose group translocator). Analysis of the reaction products in the medium revealed that several enzymic processes are going on during incubation with UDP-glucose such as production of hexose phosphates, UMP, and sugars, all of which seem unrelated to the incorporation of radioactivity into vacuoles. The incorporated radioactivity was identified mainly as (1-->3)-beta-glucan (callose) of polymerization grades up to more than 20. Callose occurs as a contaminant at the surface of isolated vacuoles coming from the plasmalemma. The properties of UDP-glucose incorporation into the vacuolar preparation compared favorably with known properties of callose synthase. The low mol wt glucans that are found are probably degradation products of labeled callose due to hydrolases, which are liberated by centrifugation of vacuoles. The labeled disaccharide, which chromatographically had been formerly identified as sucrose, is laminaribiose. No sucrose (or sucrose phosphate) could be identified in the vacuole preparation after incubation with UDP-glucose. Thus, the mechanism of sucrose storage in sugarcane vacuoles is still open.

Journal Article↗

PubMed1985

Solubilization and purification of the ATPase from the tonoplast of Hevea.

The tonoplast-bound ATPase of Hevea brasiliensis (caoutchouc tree) was solubilized with dichloromethan and purified 100-fold with two ammonium sulfate precipitation steps and a G-200 gel filtration step. The resulting ATPase activity eluted according to a molecular mass of approximately 200 kDa and chromatographed at an isoelectric pH of 5.3. Subunits of molecular mass 110 kDa, 68 kDa, 24 kDa and 12 kDa appeared after treatment with 1% sodium dodecyl sulfate or spontaneously during storage of the solubilized ATPase. Dodecyl sulfate/polyacrylamide gel electrophoresis yielded four polypeptides of molecular mass 54 kDa, 66 kDa, 23 kDa and 13 kDa. From protein determination by ultraviolet absorption and Coomassie stain it appears that the 54-kDa and the 66-kDa polypeptides exist in multiple copies. No close resemblance to the membrane-bound ATPase of mitochondria, plastids, plasmalemma, chromaffin granules and synaptic vesicles is seen. No antibody cross-reaction to F1 of bacteria is observed. Therefore it is concluded that the vacuolar ATPase represents a novel type of ATPase. Many properties of the tonoplast-bound ATPase such as pH-dependence, substrate specificity, ion-dependence and inhibitor sensitivity did not change when the enzyme had been solubilized and purified. The phosphatase activity was lost during the purification procedure. The stimulation of ATP-hydrolysis in tonoplast vesicles by uncouplers and ionophores was absent in the solubilized ATPase, and also the stimulation by chloride was significantly reduced. Anion channel blockers, such as triphenyltin and 4,4'-diisothiocyano-2,2'-disulfonic acid stilbene, which are strong inhibitors of membrane-bound ATPase, fully or partly lost their inhibiting effect after solubilization of the ATPase. These results are interpreted to indicate that ionophores do not directly affect the ATPase molecule, whereas chloride might have a small direct effect on the ATPase besides its effect as a permeating anion.

Adenosine Triphosphatases↗

PubMedDate not supplied

Implementation of EPA's Worker Protection Standard training for agricultural laborers: an evaluation using North Carolina data.

The US Environmental Protection Agency has promulgated a Worker Protection Standard which requires that farmworkers receive pesticide safety training. The implementation of these regulations has not been evaluated. Using data collected through personal interviews with 270 Hispanic farmworkers recruited from 35 labor sites in an eight-county area, the authors analyzed the extent to which farmworkers received pesticide safety training, characteristics of the training, and variations in knowledge and safety behavior. Approximately a third of the farmworkers reported having ever received information or training on pesticide safety, and 25.6% reported having received training in the year in which they were interviewed. Workers with H2A visas were significantly more likely to have received training than workers without these visas. The training received varied in location, duration, and language. Most included the use of a video, as well as verbal presentation, and most included printed materials. However, few workers knew the ways in which they could be exposed to pesticides or reported using any method to protect themselves from pesticide exposure.

Adult↗