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Biomedical subjects

R Tucker

Publications and source records attributed to R Tucker.

At least 37 records · Page 2Linked to original sources
PubMed1997

Penciclovir cream for the treatment of herpes simplex labialis. A randomized, multicenter, double-blind, placebo-controlled trial. Topical Penciclovir Collaborative Study Group.

OBJECTIVE: To compare the safety and efficacy of topical 1% penciclovir cream with vehicle control cream (placebo) for the treatment of a recurrent episode of herpes simplex labialis (cold sores) in immunocompetent patients. DESIGN: Randomized, double-blind, placebo-controlled, patient-initiated, 2-armed, parallel clinical trial. Patients were prospectively dispensed study medication, and treatment was self-initiated by the patient within 1 hour of the first sign or symptom of a recurrence. SETTING: A total of 31 ambulatory clinics in the United States in a variety of settings, including private practices, public health facilities, and universities. PATIENTS: Otherwise healthy individuals with a history of frequent episodes of herpes simplex labialis. A total of 2209 patients were enrolled and given study medication, and 1573 initiated treatment for a recurrence. INTERVENTIONS: Topical 1% penciclovir cream or vehicle control cream. Subjects applied treatment every 2 hours while awake for 4 consecutive days. MAIN OUTCOME MEASURES: Lesion healing was the primary efficacy variable. Secondary end points included time to loss of lesion pain and time to cessation of viral shedding. RESULTS: Healing of classical lesions (vesicles, ulcers, and/or crusts) was 0.7 day faster for penciclovir-treated patients compared with those who received vehicle control cream (median, 4.8 days vs 5.5 days; hazard ratio [HR], 1.33; 95% confidence interval [CI], 1.18-1.49; P<.001). Pain (median, 3.5 days vs 4.1 days; HR, 1.22; 95% CI, 1.09-1.36; P<.001) and lesion virus shedding (median, 3 days vs 3 days; HR, 1.35; 95% CI, 1.10-1.64; P=.003) also resolved more quickly for penciclovir-treated patients compared with patients who applied the vehicle control. The efficacy of penciclovir cream was apparent when therapy was initiated early (prodrome or erythema lesion stage) and when initiated late (papule or vesicle stage). The incidence of adverse events was comparable between penciclovir and placebo groups. CONCLUSIONS: Penciclovir cream is the first treatment to clearly demonstrate an impact on the course of recurrent herpes labialis in immunocompetent patients. Efficacy was seen in all clinical and laboratory measures of the disease (lesion healing, pain resolution, and cessation of viral shedding). Faster healing and pain resolution occurred both among patients who first applied penciclovir cream in the prodrome and erythema stages and among those who started treatment in the papule and vesicle lesion stages.

Acyclovir↗
PubMed1996

Group and single-subject evaluation of a programme to promote self-care in elderly nursing home residents.

Residents and staff of a nursing home in a metropolitan area were randomly assigned to three conditions to: (a) test whether staff's use of operant behavioural management strategies (Condition 1) would cause a greater increase in residents' self-care behaviour than staff's use of mutual goal setting (Condition 2) or routine nursing care (Condition 3), and (b) examine how useful group scores were, compared to individual scores, in determining change in individual residents' behaviour due to treatment. In-service training was provided to staff in Conditions 1 and 2 but not in Condition 3. Over a period of 22 weeks, nursing staff encouraged subjects to perform targeted self-care tasks independently. Data analysis indicated significantly greater change in self-care behaviours for subjects in Condition 1 than for subjects in Conditions 2 and 3. However, visual inspection of data for each case revealed that individual scores were more useful than averages and differences between groups for determining the effectiveness of the clinical interventions.

Aged↗
PubMed1995

Factors precluding patients' discharge to the community. A geropsychiatric hospital survey.

Study subjects were the 206 inpatients at a 210-bed university-affiliated, state-operated geropsychiatric hospital in July 1993. Staff psychiatrists, using the behavioral component of the Agitation Behavior Mapping Instrument (ABMI) and a nonbehavioral component added by the authors, determined reasons why their patients could not return to the community at the time of the study. Aggression, nonbehavioral problems, and inability to care for self accounted for three-quarters of the primary reasons precluding immediate community placement. Of these three reasons, aggressive behavior was both the most common and the most correctable factor keeping subjects in the hospital. Aggressive behavior occurred most commonly among psychotic patients, intermediate among demented patients and least commonly among patients with mood disorders. The authors suggest the need to better define those aggressive behaviors and to develop effective treatments that can be transported with patients as they return to the community.

Activities of Daily Living↗
PubMed1994

Bipolar versus monopolar sphincterotomy: a prospective trial.

OBJECTIVES: To determine the frequency of complications, specifically pancreatitis, associated with endoscopic sphincterotomy, comparing the standard, monopolar electrocautery current to the bipolar system. METHODS: One-hundred consecutive patients requiring ERCP and sphincterotomy, 50 patients in each group, were randomized to receive a sphincterotomy using either the bipolar system (Bitome) or the standard monopolar system. Cannulation with the selected sphincterotome was successful in 92 patients, but crossover to the other system was necessary in eight patients, five bipolar and three monopolar. The performance of sphincterotomy was conducted similarly and by the same investigator. Excessive manipulation of the papilla during difficult cannulation was avoided, and no pre-cut, needle knife, or wire-guided assisted cannulation techniques were used in either group. RESULTS: Complications were assessed during follow-up review of charts and telephone interviews. Pancreatitis did not occur in the bipolar group; however, six patients in the monopolar group developed clinical and biochemical evidence of pancreatitis (p < 0.047). CONCLUSIONS: Sphincterotomy using bipolar technology appears to reduce the frequency of pancreatitis when compared to monopolar technology in a prospective, randomized fashion. Because bipolar electrocautery current is localized to the accessory tip, radiofrequency does not encounter impedance through the patient's body mass, and tissue injury is reduced. This fact may account for the decreased incidence of pancreatitis in the bipolar group. Larger studies are called for to support this conclusion.

Cholangiopancreatography, Endoscopic Retrograde↗
PubMed1993

Function of B cells expressing a human immunoglobulin M rheumatoid factor autoantibody in transgenic mice.

We have generated transgenic mice that express the immunoglobulin (Ig)M heavy chain and kappa light chain genes coding for a human IgM rheumatoid factor (RF), Les. Transgenic B cells expressing human IgM RF show striking similarities to their counterparts in normal humans. They comprise a significant proportion of the adult B cell population, but secrete only low levels of RF into the serum. The RF transgene-expressing B cells localize to primary B cell follicles and the mantle zone regions of secondary follicles in the spleen. Using these mice we have been able to show that one of the central functions of normal RF-expressing B cells may be to act as highly efficient antigen-presenting cells for low concentrations of immune-complexed antigen. High levels of secretion of IgM RF can not be induced under normal circumstances, although RF-expressing B cells proliferate well in vitro to both aggregated human IgG and anti-human IgM antibodies. However, these mice are not intrinsically secretion deficient. By crossing the RF transgenic mice with the autoimmune MRL/lpr background, we find a dramatic increase, > 200-fold, in levels of serum RF. The results strongly suggest that a major function of normal resting RF B cells is unrelated to antibody secretion. Rather, the RF B cells in the follicles may play a role in antigen presentation and regulation of immune responses to antibody-bound nonself-, and possibly self-antigens. This physiologic role of RF B cells may be disrupted in RF-associated autoimmune disease.

Animals↗
PubMed1992

The human carotid atherosclerotic plaque stimulates angiogenesis on the chick chorioallantoic membrane.

The chick chorioallantoic membrane was used to determine whether the carotid atherosclerotic plaque stimulates angiogenesis. Carotid endarterectomy specimens (1 mm3) with fibromuscular plaque (n = 8) and complicated plaque (n = 11) were implanted on the membrane on day nine of incubation and the response evaluated on day 11. Following fixation in situ with 10% formalin the angiogenic response was evaluated by: (1) examining whole membrane mounts, (2) quantitatively from a vascular density index and (3) from a histological study. Unmanipulated chorioallantoic membrane (n = 11) and plaque boiled prior to implantation (n = 6) served as controls. The vascularity of whole mounts of both fibromuscular and complicated plaque was greater than the controls. Vessel density of the membrane was estimated by counting the number of vessels intersecting four concentric circles (144.5 mm total circumference) placed on the formalin fixed membrane. The vascular density index due to the fibromuscular plaque (390.6 +/- 8.3) and complicated plaque (391.0 +/- 14.9) were similar (P greater than 0.9) but were significantly greater (P less than 0.001) than the unmanipulated membrane (327.9 +/- 5.6) or after treatment with the boiled plaque (283.8 +/- 15.6). Transforming growth factor beta 1 confirmed the validity of the experimental model to study angiogenesis. The histology of the chorioallantoic membrane due to either type of plaque was similar. Numerous vessels surrounded the plaque, and intraplaque vessels containing nucleated chick erythrocytes were observed. Although scattered vessels surrounded the boiled plaque, intraplaque vessels were not observed. This study demonstrates that the atherosclerotic plaque has angiogenic properties that may account for the increase in vasa vasorum that is associated with the plaque.

Allantois↗
PubMed1991

The effect of PDGF on the healing of full thickness wounds in hairless guinea pigs.

1. Platelet-derived growth factor (PDGF), administered daily for 5 days and every other day for 9 additional days or the day of wounding and the following day, caused dose dependent (0.2, 1.0 or 5.0 micrograms PDGF/wound) increased granulation tissue. 2. The two day 5.0 micrograms treatment resulted in a 73% increase and the multi-day treatment resulted in a 52% increase of alkaline phosphatase activity three days after wounding. 3. Multi-day treatment resulted in significant increases in protein synthesis (132%), vimentin content (160%) and excised wound weight (76%) three days after wounding. 4. These results indicate that limited administration of PDGF alters wound healing although multiple applications provoke a more dramatic response.

Alkaline Phosphatase↗
PubMed1990

Autoantibody production by severe combined immunodeficient mice reconstituted with synovial cells from rheumatoid arthritis patients.

In an attempt to characterize the heterogeneity of the human autoantibody response, mice with severe combined immunodeficiency were reconstituted with synovial or blood lymphocytes from patients with rheumatoid arthritis (RA). Mononuclear cells extracted from synovial fluid or tissue (SMC) were a greatly enriched source of IgM rheumatoid factor (RF)-producing cells compared to the peripheral blood mononuclear cells (PBMC) of rheumatoid arthritis patients or normal donors. Six to nine weeks after reconstitution of mice with synovial mononuclear cells, 0%-39.3% (mean = 11.4%) of total IgM consisted of IgM RF compared to 0%-0.15% (mean = 0.02%) in mice given RA PBMC and 0%-1.2% (mean = 0.34%) in mice given normal PBMC. Detectable levels of IgM RF were maintained in some mice for as long as 20 weeks after transfer. Mice reconstituted with synovial membrane or synovial fluid lymphocytes produced a heterogeneous mixture of immunoglobulins. These included other autoantibodies, such as anti-nuclear and anti-cytoplasmic antibodies, and antibodies to exogenous antigens such as the Epstein-Barr virus nuclear antigen-1 (EBNA-1). This heterogeneity is further illustrated by the demonstration that the sera from mice given synovial cells also contained IgG antibodies possessing all three major VH families (VH1, VH3 and VH4) and the four major V kappa families (V kappa 1 to V kappa 4). Autoantibody production gradually decreased with time even under circumstances where total immunoglobulin levels increased, and elevated production could not be induced by antigenic stimulation. These findings describe a new model for the analysis of human autoantibody production.

Animals↗
PubMed1990

Nursing care of the patient with non-Hodgkin's lymphoma. A case study.

A patient's significant life events, such as the diagnosis of cancer, coupled with critical developmental milestones provide particular challenges to nurses caring for young adults. A case study format is used to identify nursing care priorities throughout the diagnosis and treatment of a young adult male with non-Hodgkin's lymphoma. Diagnosis and treatment protocols are discussed to provide a background for nursing assessment and interventions. Nursing implications related to the treatment protocol are incorporated as are implications based on the physical and psychological impact of the disease and necessary life-style changes. Stressors created by the disease and treatments are identified, and the support of patient coping strategies and continued achievement of developmental tasks are addressed.

Adult↗
PubMed1990

Regional hyperthermia combined with high energy shock wave treatment on Dunning prostate tumors.

Male Copenhagen rats implanted with Dunning R3327 prostate carcinoma were treated with regional hyperthermia and high energy shock waves (HESW). Twenty-four rats were divided into four equal groups. All rats in one group were matched with the corresponding rats in the other three groups according to tumor size. Hyperthermia was created by the resistive heating of a 22-gauge 1.5-cm needle; HESW were generated by the Dornier XL-1 experimental lithotripter. In two hyperthermia treatments administered 48 hours apart, the tumor was heated to 46.5 degrees C for 2 hours; HESW treatment involved 1,600 shocks at 18 kV. Twenty-nine days after initiation of this study, animals were sacrificed and tumor growth calculated. Tumor growth in group 1 (combined hyperthermia and HESW) was significantly delayed between the 7th and 29th day (p = 0.05). In group 2 (HESW alone), tumor growth was significantly delayed between the 7th and 22nd day (p = 0.01), while tumor growth in group 3 (hyperthermia alone) was delayed between the 3rd and 22nd day (p = 0.02). On day 22, mean percent change in tumor growth in the control group exceeded that of group 1 by 449% (p = 0.015) as well as that of groups 2 and 3, by 350% (p = 0.034) and by 268% (p = 0.049), respectively. As previous reports demonstrate the efficacy of hyperthermia in combination with irradiation or chemotherapy for the treatment of prostate carcinoma, our results indicate hyperthermia in combination with HESW may also be a useful treatment modality.

Animals↗
PubMed1990

Non-Hodgkin's lymphoma. Understanding the disease.

An overview providing current knowledge about non-Hodgkin's lymphoma (NHL) is presented. The pathophysiology, epidemiology, clinical signs and symptoms, and the classification system of NHL are outlined. In addition, the staging of NHL, diagnostic procedures, treatment options, and recommendations related to follow-up care and managing recurrent disease are presented.

Adult↗
PubMed1989

Sulfation pharmacogenetics: correlation of human platelet and small intestinal phenol sulfotransferase.

Phenol sulfotransferase (PST) catalyzes the sulfate conjugation of phenolic drugs. All human tissues studied contain a thermostable (TS) form of PST, which catalyzes the sulfate conjugation of "simple" phenols such as p-nitrophenol, and a thermolabile (TL) form, which catalyzes the sulfation of dopamine and other monoamines. In the present study we tested the hypothesis that genetically controlled levels of TS and TL PST activity in the platelet, as well as inherited variations in the thermal stability of platelet TS PST, might reflect those same characteristics of the enzyme in the less accessible tissue, human small intestinal mucosa. Platelet TS and TL PST activities and TS PST thermal stability were measured in blood samples from 45 randomly selected healthy subjects, and 14 of those subjects were selected to have intestinal biopsies performed. There was a significant correlation between levels of platelet and jejunal mucosal TS PST activity (rs = 0.574, p less than 0.030), but there was not a significant correlation between levels of TL PST activity in the two tissues (rs = 0.265, p = 0.368). There was also a significant correlation between the trait of TS PST thermal stability in the two tissues (rs = 0.828, p less than 0.0001). These observations suggest that inherited variations in TS PST activity and thermal stability in an easily obtained tissue, the platelet, might be used to predict individual differences of those properties of the enzyme in the human small intestine, an organ that plays an important role in drug metabolism.

Adult↗
PubMed1989

An examination of loneliness among elderly Canadian seasonal residents in Florida.

As part of a larger study focusing on different facets of the lives of 2,731 older Canadians who seasonally reside in Florida, we investigated primarily the extent of family and friendship contacts and the loneliness expressed by these older Canadians. The data were collected using a questionnaire that was distributed and returned by mail. The sample was taken from the subscription list of a newspaper in Florida that was a subsidiary of a large Canadian newspaper. The results show a population that was relatively young, married, in generally good health, and with rather extensive contacts with family and friends while residing in Florida. Nevertheless, more than a fifth indicated they were at least somewhat lonely. Results, using discriminate function analysis, showed that those more lonely were younger, female, less educated, not married, in poorer physical health, had fewer Florida friends, and had more children who lived near them in Canada, but fewer children who lived near them in the United States. Implications of the results are discussed.

Age Factors↗
PubMed1989

Health care utilization of Canadian snowbirds: an example of strategic planning.

Older English-speaking Canadian seasonal migrants to Florida (N = 2046) were surveyed during the winter of 1986. They are users of two health care systems and are generally in good health. When they do need to use health care resources, however, they show a distinct preference for the Canadian system. There is a sensitivity to health concerns, especially among the older of the migrants. This sensitivity generates considerable precautionary behavior including pretravel visits to their Canadian family doctors, stocking up on drugs before the trip, and taking out health insurance for Canadians traveling abroad. The behavior is strategic in that it is both intentional and oriented to contingencies. Cost of health care may be a motivating factor because such strategic behavior is inversely related to income in this relatively affluent migrating population. The flock of Canadian snowbirds is not likely to place exorbitant demands on the U.S. health care system.

Aged↗