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J C Scott

Publications and source records attributed to J C Scott.

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

Molecular genetic analysis of human cystic hydatid cases from Poland: identification of a new genotypic group (G9) of Echinococcus granulosus.

We have used nuclear (ribosomal ITS1) and mitochondrial (ND1) sequences to characterize human and pig isolates of Echinococcus granulosus collected by fine needle aspiration biopsy (FNAB) in Poland. The data indicate clearly that the Polish patients were not infected with the common sheep strain (G1 genotype) of E. granulosus, normally associated with human cystic hydatid infection. Instead, the hydatid parasite infecting the Polish patients shares very similar ND1 sequence with the previously characterized pig (G7) genotype but it also exhibits some clear differences. In particular, E. granulosus DNA from the Polish patients amplified a single ITS1 fragment in PCR and distinct ITS1-RFLP patterns were obtained after restriction digestion. The form of hydatid isolated from the Polish patients appears, therefore, to represent a distinct, previously undescribed genotype (designated G9) of E. granulosus.

Adult↗
PubMed1996

Association of estrogen replacement therapy with the risk of osteoarthritis of the hip in elderly white women. Study of Osteoporotic Fractures Research Group.

OBJECTIVE: To determine whether postmenopausal estrogen replacement therapy is associated with a reduced risk of radiographic findings of osteoarthritis (OA) of the hip. DESIGN: Cross-sectional study. SUBJECTS: White women (N = 4366; age, > or = 65 years) who were participants in a cohort study of osteoporotic fractures. MEASUREMENTS AND METHODS: Radiographs of the pelvis that were obtained in all subjects were assessed for radiographic features of OA of the hip on a summary scale of 0 (none) to 4 (severe OA). Postmenopausal estrogen use was assessed by interview. The association of current and past oral estrogen use with OA of the hip was analyzed by using logistic regression, adjusting for potential confounding variables (eg, indicators of osteoporosis and correlates of estrogen use). RESULTS: Five hundred thirty-nine women (12.3%) had mild or greater radiographic findings of OA of the hip in at least 1 hip, and 214 women (4.9%) had moderate to severe findings; 17% and 24% of the women were current and past users of oral estrogen, respectively. Women who were currently using oral estrogen had a significantly reduced risk of any OA of the hip (adjusted odds ratio [OR], 0.62; 95% confidence interval [CI], 0.49-0.86) and moderate to severe manifestation of disease (OR, 0.54; 95% CI, 0.33-0.88). Current users who had taken estrogen for 10 years or longer had a greater reduction in the risk of any OA of the hip (OR, 0.57; 95% CI, 0.40-0.82) compared with that of users for less than 10 years (OR, 0.75; 95% CI, 0.47-1.24). Current estrogen use for 10 years or longer was associated with a nonsignificant trend for a reduced risk of moderate to severe symptomatic disease (OR, 0.59; 95% CI, 0.28-1.29). CONCLUSION: Postmenopausal estrogen replacement therapy may protect against OA of the hip in elderly white women.

Aged↗
PubMed1996

Smoking and mortality among older women: the study of osteoporotic fractures.

BACKGROUND: Relatively few studies have been focused on the effect of smoking among older individuals. The goal of this study is to investigate the relationship between smoking status and cause-and age-specific mortality among elderly women. METHODS: Women aged 65 years and older and living in four geographical areas (Baltimore, Md, Minneapolis, Minn, Pittsburgh, Pa, and Portland, Ore) were recruited from various population-based listings for participation in the multicenter Study of Osteoporotic Fractures between September 1986 and October 1988 (N=9704). During a mean follow-up of 4.9 years (<99% complete), 751 deaths occurred. The date and cause of death were ascertained, and the relationship between mortality and current and past smoking status was analyzed using Cox proportional hazards modeling techniques. RESULTS: Compared with nonsmokers, women smokers aged 65 to 74 years have a more than twofold increase in mortality attributable to increases in both cardiovascular and cancer mortality; death from smoking-related cancers increased eight- to 10-fold. Women 75 years and older who smoke have a small overall increased relative risk (RR) of mortality (RR=1.4; 95% confidence interval [CI], 0.9 to 2.3), but more than five-fold increased risk of dying from a smoking-related cancer (RR=5.2; 95% CI, 1.6 to 16.8). All-cause and cardiovascular death rates approach those of nonsmokers within 10 years after a woman quits smoking; morality from smoking-related cancers remains elevated for at least 23 years. CONCLUSIONS: The harmful effects of continuing to smoke are apparent even among women aged 75 years and older.

Aged↗
PubMed1996

Telemedicine in Micronesia.

Distance and isolation profoundly affect the delivery of health care in the islands of Micronesia. The lack of specialty services on most of the islands has led to a costly off-island referral system that strains health care budgets. Care providers there have incorporated advances in telecommunications to create a telemedicine network amongst themselves and with a tertiary care hospital in Hawaii. They developed an interactive video conferencing system, a still-image transmission network, and a data transfer network for use principally in patient care and continuing education. Patients now receive earlier evaluation by off-island specialists as part of an effort to improve the appropriateness of off-island referrals. Regularly scheduled medical lectures are broadcast from Pohnpei, a main island, to physicians in several more remote locations. Transmission costs are kept low by using, when possible, preexisting public-service satellites, such as the PEACESAT system that serves the entire Pacific basin. The telemedicine system is evolving, and its success depends greatly on the cooperative relationships among the partners.

Education, Medical↗
PubMed1996

Kaiser Colorado's Cooperative Health Care Clinic: a group approach to patient care.

A Kaiser Permanente pilot project demonstrates that managing health status with patients on a group basis versus one-on-one office visits can improve health care delivery services and reduce unnecessary resource utilization. Kaiser's Cooperative Health Care Clinic (CHCC) in Denver, Colorado, uses a multidisciplinary team to successfully provide care to elderly members with chronic conditions.

Activities of Daily Living↗
PubMed1996

Validity of self-reported rheumatoid arthritis in elderly women.

OBJECTIVE: To determine the validity of a self-reported physician diagnosis of rheumatoid arthritis (RA) in elderly women. METHODS: Women with self-reported RA were contacted and permission requested to contact their physician. Physicians were mailed a questionnaire requesting information on the subject's arthritic condition. Hand radiographs obtained at study entry were read for changes of RA. RESULTS: The self-reported diagnosis of RA could be confirmed in 26 (21%) individuals. CONCLUSION: The positive predictive value of self-reported RA was low in this cohort. Caution needs to be exercised in the use and interpretation of self-report data concerning arthritic conditions in epidemiologic studies.

Aged↗
PubMed1995

Radiographic osteoarthritis of the hip and bone mineral density. The Study of Osteoporotic Fractures Research Group.

OBJECTIVE: To examine the cross-sectional association between radiographic features of hip osteoarthritis (OA) and bone mineral density (BMD) of the hip, spine, and appendicular skeleton among Caucasian women ages 65 and older who were participating in the Study of Osteoporotic Fractures. METHODS: Pelvis radiographs of 4,855 subjects were assessed for individual radiographic features of hip OA: osteophytes, joint space narrowing, subchondral sclerosis, cysts, and femoral head deformity. Hips were graded on a summary scale of 0 (no OA) to 4 (severe OA) based on the number of radiographic features present. Appendicular BMD was measured in all subjects, and hip and spine BMD in 84% of the group. We used linear regression to examine the association of BMD with hip OA, and to adjust for age, weight, and other determinants of bone mass. RESULTS: Three hundred fifty-one women (7.2%) had mild (grade 2) and 228 (4.7%) had moderate to severe (grade 3-4) radiographic evidence of hip OA. Women with grade 3-4 hip OA had a higher age-adjusted BMD at the femoral neck and Ward's triangle (9-10%; P < 0.0001), trochanter (4%; P < 0.01), lumbar spine (8%; P < 0.0001), and distal radius and calcaneus (5%; P < 0.0001 [for each comparison]) compared with those with grade 0-1 OA in the worse hip. Elevations in BMD were greatest in the femoral neck of hips with OA, in women with bilateral hip OA, and in women with hip osteophytes. These findings were essentially unchanged by adjustment for determinants of bone mass. CONCLUSION: Elderly Caucasian women with moderate to severe radiographic hip OA had higher BMD in the hip, spine, and appendicular skeleton than did women without hip OA. Our findings are consistent with a role of elevated BMD in the pathogenesis of hip OA.

Aged↗
PubMed1995

Survey of global telemedicine.

The number and scope of telemedicine projects and applications world-wide are growing rapidly along with exponential expansions in national and international information infrastructures and computer capabilities to support them. To track these rapid changes, the Center for Public Service Communications (CPSC) of Arlington, VA, developed the Telemedicine and Information Technologies in Health Care: Project Tracking Document for the National Aeronautics and Space Administration (NASA). This document is maintained by CPSC and frequently updated. It tracks the following areas in telemedicine and health care informatics: (1) major existing Federal grant and other assistance programs and activities; (2) legislation effecting policy in these areas; (3) projects using various technologies throughout the US; and (4) telemedicine projects/interests in other nations. This paper is a survey of international (global) telemedicine activities that are outlined in that document.

Australia↗
PubMed1995

Gene cloning and complete nucleotide sequence of philippine Schistosoma japonicum paramyosin.

The development of an effective vaccine is recognised as a necessary adjunct to the control of schistosomiasis japonica, a disease affecting several million people in China and the Philippines. Currently, recombinant Schistosoma japonicum molecules are considered most suitable for large scale vaccine production and a number of genes encoding vaccine candidate polypeptides have been cloned and expressed (see Waine et al., 1993a). One of the molecules providing most promise as a vaccine target is paramyosin (Butterworth, 1992), a major structural protein of thick filaments in the muscle of most invertebrates; paramyosin genes have now been cloned from a range of parasitic helminths, including schistosomes (Limberger and McReynolds, 1990; Laclette et al., 1991; Dahmen et al., 1993; Landa et al., 1993; Mühlschlegel et al., 1993, Nara et al., 1994). The cloning and nucleotide sequence of S. Japonicum paramyosin is described.

Animals↗
PubMed1995

The association of radiographic changes of osteoarthritis of the hand and hip in elderly women.

OBJECTIVE: To examine the association of radiographic features of hand and hip osteoarthritis (OA) in elderly women. METHODS: Hand and hip radiographs were read for changes of OA from a sample of 1422 women aged 65 and above who were participants in the Study of Osteoporotic Fractures. Definite hip OA required the presence of 2 or more of the following: moderate or large osteophytes, moderate or severe joint space narrowing, subchondral sclerosis, cysts, and femoral head deformity. Definite hand OA required moderate or large osteophytes at 2 or more of the following 6 sites: 2nd and 3rd distal and proximal interphalangeal joints and 1st interphalangeal and carpometacarpal joints. Data were analyzed using multiple logistic regression adjusting for age, weight at age 50, and current height. RESULTS: Overall, 147 (10.4%) women had radiographic changes of definite hip OA and 68 (4.8%) had severe hip OA; 56 had bilateral and 87 had unilateral disease. Definite hand OA was present in 732 (51.4%) women. Hand OA was significantly associated with definite hip OA [odds ratio (OR) = 3.25, 95% confidence intervals (CI) 2.19, 4.84], and severe hip OA (OR = 3.23, 95% CI 1.82, 5.73). Hand OA was significantly associated with bilateral hip OA (OR = 3.54, 95% CI 1.87, 6.73) as well as unilateral hip OA (OR = 3.06, 95% CI 1.84, 5.08). CONCLUSION: These data are consistent with the inclusion of radiographically defined hip OA in the construct of generalized OA, particularly in elderly women.

Aged↗
PubMed1994

Smoking, alcohol, and neuromuscular and physical function of older women. Study of Osteoporotic Fractures Research Group.

OBJECTIVE: To determine the associations of current and lifetime smoking and alcohol use with physical function in an older population. DESIGN: Survey. SETTING: Four clinic centers in the United States. PARTICIPANTS: A total of 9704 community-dwelling, ambulatory white women 65 years or older recruited from four areas of the United States. MAIN OUTCOME MEASURES: Twelve performance tests of muscle strength, agility and coordination, gait and balance, and self-reported functional status. RESULTS: Compared with women who never smoked, current smokers had significantly poorer function on all of the performance measures except grip strength after adjusting for age, history of stroke, body mass index, clinic site, physical activity, and alcohol use (P < .05). This decrease in function was 50% to 100% as great as that associated with a 5-year increase in age, and most measures worsened with increasing numbers of pack-years. Compared with current moderate drinkers, nondrinkers had significantly poorer function on all of the performance measures except tandem walk (P < .05). Evaluation of a dose effect with alcohol was limited by the small number of heavy drinkers in the study. CONCLUSIONS: In this population, women who currently smoke are weaker and have poorer balance and poorer performance on measures of integrated physical function than nonsmokers. Smoking is associated with a decline in physical function. Current moderate drinkers have better physical function compared with nondrinkers, but associations of function with heavy drinkers could not be assessed.

Activities of Daily Living↗
PubMed1994

Purification of a recombinant Schistosoma japonicum antigen homologous to the 22-kDa membrane-associated antigen of S. mansoni, a putative vaccine candidate against schistosomiasis.

We describe the cDNA cloning, overproduction and purification of a 22.6-kDa antigen from the human blood fluke Schistosoma japonicum. A 777-bp cDNA (C32) was isolated from a S. japonicum lambda ZAPII cDNA expression library immuno-screened with hyperimmune rabbit serum (HRS) raised against soluble adult S. japonicum proteins. The open reading frame of C32 encodes a protein of 191 amino acids (aa) which exhibits 71% identity to a 22.6-kDa membrane-associated antigen of S. mansoni, a putative vaccine candidate for schistosomiasis. We have identified a sequence motif known as an EF-hand calcium-binding domain in both the S. japonicum and S. mansoni aa sequences, suggesting that the 22.6-kDa antigens are able to bind Ca2+. Further, we have, for the first time, obtained the 22.6-kDa antigen in purified, non-denatured, recombinant form, and in sufficient quantity to assess the protective value of the molecule in vaccination/challenge experiments. This was achieved by synthesizing the schistosome antigen with a short polyhistidine tag fused to the N-terminus which was then used for subsequent affinity purification. The recombinant protein was purified under non-denaturing conditions using nickel-chelate affinity chromatography.

Amino Acid Sequence↗
PubMed1994

Deficient expression of co-stimulatory molecules on Leishmania-infected macrophages.

Co-stimulatory signals are necessary for the full activation of T cells for growth and effector function. As co-stimulatory molecules are normally regulated in their expression, it has been suggested that microorganisms enhance their expression on host antigen-presenting cells (APC), thus allowing efficient generation of anti-microbial immunity. We here describe experiments which demonstrate that infection of macrophages, both in vitro and in vivo, by the protozoan parasite Leishmania donovani fails to trigger expression of co-stimulatory molecules B7-1 and heat-stable antigen on these APC. Furthermore, infection with this parasite inhibits the macrophage response to normal regulatory signals, such as bacterial lipopolysaccharide. These changes in the cell surface are mirrored in functional studies of co-stimulation in vitro. Together, these data suggest a further facet of parasite interference in host immunity, but also indicate a potential new target for immunotherapy.

Animals↗
PubMed1994

Diminished brain glucose metabolism is a significant determinant for falling rates of systemic glucose utilization during sleep in normal humans.

Systemic glucose utilization declines during sleep in man. We tested the hypothesis that this decline in utilization is largely accounted for by reduced brain glucose metabolism. 10 normal subjects underwent internal jugular and radial artery cannulation to determine cerebral blood flow by N2O equilibrium technique and to quantitate cross-brain glucose and oxygen differences before and every 3 h during sleep. Sleep stage was graded by continuous electroencephalogram, and systemic glucose turnover was estimated by isotope dilution. Brain glucose metabolism fell from 33.6 +/- 2.2 mumol/100 g per min (mean +/- SE) before sleep (2300 h) to a mean nadir of 24.3 +/- 1.1 mumol/100 g per min at 0300 h during sleep (P = 0.001). Corresponding rates of systemic glucose utilization fell from 13.2 +/- 0.8 to 11.0 +/- 0.5 mumol/kg per min (P = 0.003). Diminished brain glucose metabolism was the product of a reduced arteriovenous glucose difference, 0.643 +/- 0.024 to 0.546 +/- 0.020 mmol/liter (P = 0.002), and cerebral blood flow, 50.3 +/- 2.8 to 44.6 +/- 1.4 cc/100 g per min (P = 0.021). Brain oxygen metabolism fell commensurately from 153.4 +/- 11.8 to 128.0 +/- 8.4 mumol/100 g per min (P = 0.045). The observed reduction in brain metabolism occurred independent of stage of central nervous system electrical activity (electroencephalographic data), and was more closely linked to duration of sleep. We conclude that a decline in brain glucose metabolism is a significant determinant of falling rates of systemic glucose utilization during sleep.

Activity Cycles↗
PubMed1994

The random amplification of polymorphic DNA can discriminate species and strains of Echinococcus.

The random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR), also called arbitrary priming PCR (AP-PCR), is a DNA polymorphism assay based on the amplification of genomic DNA using a single oligonucleotide primer of arbitrary nucleotide sequence. Using carefully controlled conditions, the random amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR) proved useful for distinguishing Echinococcus species and genetically distinct strains of Echinococcus granulosus. Amongst twenty random 10 mer oligonucleotide primers tested, 4 (5'-GGGAATTCGG-3', 5'-GGCTGCAGAA-3', 5'-GGAGTACTGG-3', 5'-CCTCTAGACC-3') were most suitable for producing complex but characteristic patterns for discrimination purposes. Although the method amplifies vertebrate DNA, the resulting patterns do not interfere with the identification of Echinococcus isolates. Consequently, the technique can still be used effectively to distinguish Echinococcus species and strains even if host contamination occurs during the course of parasite collection. The approach complements several other methods, based on direct DNA examination, recently developed in our laboratory, which also allow unambiguous discrimination of Echinococcus genotypes.

Animals↗
PubMed1993

Factors associated with appendicular bone mass in older women. The Study of Osteoporotic Fractures Research Group.

OBJECTIVE: To determine the factors associated with appendicular bone mass in older women. DESIGN: Cross-sectional analysis of baseline data collected for a multicenter, prospective study of osteoporotic fractures. SETTING: Four clinical centers in Baltimore, Maryland; Minneapolis, Minnesota; Portland, Oregon; and the Monongahela valley, Pennsylvania. PATIENTS: A total of 9704 ambulatory, nonblack women, ages 65 years or older, recruited from population-based listings. MEASUREMENTS: Demographic and historical information and anthropometric measurements were obtained from a baseline questionnaire, interview, and examination. Single-photon absorptiometry scans were obtained at three sites: the distal radius, midradius, and calcaneus. Multivariate associations with bone mass were first examined in a randomly selected half of the cohort (training group) and were then tested on the other half of the cohort (validation group). RESULTS: In order of decreasing strength of association, estrogen use, non-insulin-dependent diabetes, thiazide use, increased weight, greater muscle strength, later age at menopause, and greater height were independently associated with higher bone mass. Gastric surgery, age, history of maternal fracture, smoking, and caffeine intake were associated with lower bone mass (all P < 0.05). For example, we found that 2 or more years of estrogen use was associated with a 7.2% increase in distal radius bone mass, whereas gastrectomy was associated with an 8.2% decrease in bone mass. The associations between bone mass and dietary calcium intake and rheumatoid arthritis were inconsistent. Alcohol use, physical activity, use of calcium supplements, pregnancy, breast-feeding, parental nationality, and hair color were among the many variables not associated with bone mass. Multivariate models accounted for 20% to 35% of the total variance of bone mass. CONCLUSIONS: A large number of factors influence the bone mass of elderly women; however, age, weight, muscle strength, and estrogen use are the most important factors.

Aged↗
PubMed1993

Reproductive correlates of bone mass in elderly women. Study of Osteoporotic Fractures Research Group.

Results from previous studies of reproductive factors and bone density have been conflicting; some demonstrate a beneficial effect, but others show a detrimental effect on bone density. The present study investigates the association of parity, lactation, and menstruation with radial bone density in 2230 white women, 65 years of age and older. Bone density was assessed by single-photon absorptiometry. Linear multiple regression was utilized to determine if reproductive factors were associated with radial bone density. The number of births, duration of menstrual bleeding, age at menarche, and years menstruating were significant independent predictors of postmenopausal bone density of the radius. A 1.4% increase in distal radius bone density was observed with each additional birth. Women who began menstruation at age 9 had 6.3% higher bone density than women who began at age 16. Women who menstruated for 3 days during each menstrual cycle had 2.8% less distal radius bone density than women who bled for 7 days. Each decade of menstruation was associated with a 2% greater distal radius bone density. No difference in bone density was demonstrated for women who breast-fed and women who did not. Length of the menstrual cycle, amount of menstrual flow, and irregularity of the menstrual cycle were not significantly associated with radial bone mineral density. In conclusion, pregnancy and menstruation are associated with postmenopausal bone density of the radius.

Abortion, Induced↗