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PubMed2002

The financial experience of hospitals with HMO contracts: evidence from Florida.

In this paper, we report results from the first study to systematically examine trends in the financial experience of hospitals with health maintenance organization (HMO) contracts. The longitudinal analysis (1990 through 1997) focused on hospitals in Florida. Hospital operating margins for HMO contracts grew tighter toward the end of the study period when the median margin was less than 1%. Teaching hospitals had operating margins that on average were below that of their nonteaching counterparts. The continued growth of HMOs and other managed care entities may have important implications for the future financial viability of U.S. hospitals.

Catchment Area, Health↗
PubMed1998

Evaluation of the AMPLICOR cytomegalovirus test with specimens from human immunodeficiency virus-infected subjects.

The AMPLICOR cytomegalovirus (CMV) test, a new qualitative assay for the detection of CMV DNA in plasma, was compared to conventional methods and quantitative PCR (Q-PCR) assays by using leukocytes and plasma from 179 blood samples from subjects with AIDS. For the diagnosis of CMV disease, cell-based assays such as a Q-PCR with polymorphonuclear leukocytes (Q-PCR-PMNL) and a pp65 antigenemia assay had the highest sensitivities but suffered from a lack of specificity. The best agreement between the results of the Q-PCR-PMNL assay and those of the AMPLICOR test was found when a threshold diagnostic value of 690 copies per 10(5) cells was selected for the Q-PCR-PMNL assay. In that context, the AMPLICOR CMV test had a sensitivity of 96.4% and a specificity of 95.3% when results were compared to results of the cell-based PCR assay. This threshold was close to the one described as associated with the best sensitivity and specificity for the diagnosis of CMV disease in a recently published study (4). Blood samples that tested positive by the Q-PCR-PMNL assay but negative by the AMPLICOR CMV test were associated with viral loads (mean, 785 copies, median, 96 copies per 10(5) leukocytes) lower than the viral loads of blood samples that tested positive by both assays (mean, 21,452 copies; median, 9,784 copies per 10(5) leukocytes) (P = 0.003). The AMPLICOR CMV test gave positive results at least 48 days before the development of symptomatic CMV disease in a longitudinal analysis of a limited subset of patients (n = 6) from whom sequential specimens were available for testing. In conclusion, the AMPLICOR CMV test is a very convenient assay combining rapidity, simplicity, and the possibility of batch testing. A positive result by this test seems particularly important since this implies, in most instances, the presence or the imminence of CMV disease, although a negative test result does not rule out disease.

AIDS-Related Opportunistic Infections↗
PubMedDate not supplied

Effects of chronic exposure to diisocyanates.

The pulmonary effects of chronic exposure to isocyanates (mainly MDI) at low levels (less than 0.02 ppm) were studied in a five year longitudinal survey of workers from two factories producing polyurethane foam. A respiratory questionnaire, flow volume curves and a single breath CO diffusion test were done at the beginning of the survey and repeated five years later; 318 workers (214 men, 104 women) of whom 83 (group I) were unexposed, 117 indirectly exposed (group II) and 118 directly exposed to isocyanates (group III) were examined. Five years later, half of the initial cohort only was still active and re-examined. The longitudinal analysis distinguished unexposed workers at both examinations (group A), indirectly at both examinations (group. B), directly exposed at both examinations (group. C) and workers exposed directly at first examination and retired from risk at the second (group. D). The decline of VC and FEV1 was not significantly different between exposed and unexposed. On the contrary, DLCO declined significantly in group C compared to the others. The results indicate that even at 'safe levels', chronic exposure to isocyanates involved a respiratory risk.

Air Pollutants, Occupational↗
PubMed2005

Early childhood development interventions and cognitive development of young children in rural Vietnam.

Little is known about the long-term benefits of interventions that aim to promote early childhood development programs. The goal of this research was to determine whether an early childhood development intervention added to a nutrition intervention during preschool ages had lasting effects on the cognitive development of school-age children in communes of Thanh Hoa province in rural Vietnam. The study focused on a total of 313 children aged 6.5-8.5 y (grades 1 and 2 in primary school) in 2 communes that were exposed to nutrition intervention or nutrition and early childhood development (ECD) intervention from 1999 to 2003. Measurements of height and cognitive test scores (Raven's Progressive Matrices Test) were collected from the children; household characteristics were determined by interviews with mothers. Longitudinal analysis was performed by integrating the data with that collected from the same children in past surveys. Significant effects of the ECD intervention compared with the nutrition intervention were detected. The beneficial effect of ECD intervention on the cognitive test scores was large for the most nutritionally challenged children whose height-for-age Z-scores declined or remained in the stunted range. The findings help provide useful insights into the development of an effective integrated model of ECD and nutrition intervention for children in rural Vietnam.

Body Height↗
PubMed2002

Hepatocyte growth factor in human breast milk acts as a trophic factor.

To evaluate the significance of hepatocyte growth factor (HGF) in milk in the perinatal period, we examined immunoreactive HGF levels and bioactivity in human milk. Human milk samples were obtained from women at various postpartum ages, and the levels of HGF were measured by ELISA. In the cross sectional study, the concentration of milk HGF from term deliveries showed a significant inverse correlation with progress of lactation, whereas in cases of preterm delivery concentrations, levels remained high after a long period of lactation. In the longitudinal analysis, the contents of HGF in colostrum, transitional, and mature milk from preterm deliveries were significantly be higher than those from term deliveries. Although mature milk from term and preterm deliveries contained significantly lower levels of HGF than colostrum, high levels of HGF persisted in mature milk from preterm deliveries. After partial purification, immunoblotting analysis showed the presence of both alpha- and beta-chains of HGF. HGF in milk stimulated proliferation of rat hepatocytes in primary culture, which was inhibited by supplementation with anti-HGF antibody. Thus, a high concentration of bioactive HGF is present in human milk in the postpartum period. Our results suggest that HGF in milk acts as a trophic factor for the gastrointestinal tract in neonates.

Adult↗
PubMed2004

Depression after stroke: a prospective epidemiological study.

OBJECTIVES: To elucidate the relationship between stroke and depressive symptoms and to determine whether disability or cerebrovascular risk factors mediate that relationship. DESIGN: A prospective longitudinal epidemiological survey. SETTING: The mid-Monongahela Valley, a rural, nonfarm, low-socioeconomic-status community. PARTICIPANTS: Random sample of 1,134 subjects aged 65 and older. MEASUREMENTS: The dependent variable was clinically significant depressive symptoms, as defined by five or more symptoms on the modified Center for Epidemiological Studies Depression scale. The independent variables were demographics (age, sex, education), stroke, number of impaired instrumental activities of daily living (IADLs), diabetes mellitus, hypertension, atherosclerotic heart disease, and smoking. Logistic regression analyses were conducted for cross-sectional and longitudinal models examining whether stroke was associated with or predicted depressive symptoms, with other associated factors included as covariates. RESULTS: Clinically significant depressive symptoms were cross-sectionally associated with stroke (odds ratio (OR)=3.5, 95% confidence interval (CI)=1.4-8.3), diabetes mellitus (OR=2.8, 95% CI=1.7-4.6; P</=.05), and IADL impairment (OR=1.6, 95% CI=1.4-1.8; P<.05). Longitudinal analysis demonstrated that stroke (OR=6.3, 95% CI=1.7-23.2) and depressive symptoms at baseline (OR=15, 95% CI=7.7-29.5) predicted subsequent clinically significant depressive symptoms measured 2 years later, whereas education was protective (OR=0.4, 95% CI=0.2-0.8). CONCLUSION: Stroke survivors have a greatly elevated risk for clinically significant depressive symptoms even 2 or more years after index stroke, independent of functional disability, cerebrovascular risk factors, and previous depressive symptoms.

Activities of Daily Living↗
PubMed1995

Change in job and marital experiences and change in psychological distress: a longitudinal study of dual-earner couples.

Are changes in job quality more closely linked to changes in distress for men than for women? Conversely, are changes in marital quality more closely linked to changes in distress for women than for men? These questions were addressed in a longitudinal analysis of a random sample of 210 full-time employed dual-earner couples. Change over time in job role quality was significantly associated with change over time in distress, and the magnitude of the relationship differed little, if at all, by gender. In contrast, change over time in marital role quality was also associated with change in distress, but the magnitude of the association depended on gender. Among full-time employed married women, change in marital experience was more closely linked to change in distress than among their husbands.

Adult↗
PubMed1995

[Health appraisal for work adjustment of freshmen employees--information on health checkup just after entering the corporation and condition in the next fiscal year].

In 1990, 365 (males: 197, females: 168) freshmen employees at the headquarters of a large corporation were examined just after being hired in order to observe their health status. We collected (1) data of physical examinations and questionnaires for symptoms as an ordinary health checkup, (2) information on work adjustment, life patterns, and personal characteristics through interviews conducted by ten public health nurses, and (3) personal records, e.g. birth year. Statistical analyses revealed some notable findings as follows: (1) subjects with higher blood pressure had higher scores of extrovert personality among males, (2) female subjects with greater body mass index had higher scores in such manifestations of personal characteristics such as aggression and discontent with superiors, (3) higher scores of personal characteristics were noted among female subjects working in technical sections, (4) positive correlation between the scores of work adjustment and personal characteristics, (5) higher scores of undesirable life patterns among males and of work maladjustment among elder females, (6) unbalanced meal quality of subjects from rural areas, (7) higher mental tension among younger males from rural areas, and (8) higher scores of dependency and lower morale among younger female subjects. Information on health problems was collected over the 1.5 yrs that followed. More problems were detected among females than among males and among younger females than among elder females. Longitudinal analysis was carried out from just after entry into the company for approximately 1.5 yrs. Health problems in females could be predicted by the data on personal characteristics and work adjustment just after entry. Risk of health problems in male freshmen employees with hobbies and unhealthy drinking habits over the 1.5 yrs that followed was higher than in others. It was concluded that a health interview for freshmen employees by public health nurses is valuable for health care, obtaining information regarding work adjustment, life patterns, and personal characteristics.

Adult↗
PubMed2003

The effectiveness of autologous chondrocyte implantation for treatment of full-thickness articular cartilage lesions in workers' compensation patients.

This prospective longitudinal analysis evaluated the effectiveness of autologous chondrocyte implantation in 24 workers' compensation patients with articular cartilage injuries >2 cm2. Mean lesion size was 4.7 cm2, (range: 2-10 cm2). Nineteen lesions were on the distal femur and 5 were on the patella. Clinical assessment scores improved from a mean of 3.2 at baseline to 6.8 one year postoperatively, with 78% rated good or excellent. Among patients with > or = 1-year follow-up, 63% returned to unrestricted work status at a mean of 7 months; an additional 22% returned to modified work.

Adult↗
PubMed1986

Air conditioning and television as protective factors in arboviral encephalitis risk.

In California, the advent of television and air conditioned housing has coincided with a general decrease in mosquito-borne viral encephalitis cases in humans in the past 25 years. During this same period, levels of vector populations, virus activity in vectors, birds, and horses has been high at times. Air conditioning and television encourage persons to remain indoors during summer evenings, the primary time when infected Culex tarsalis transmit western equine encephalomyelitis and St. Louis encephalitis viruses. The attack rates for these 2 diseases in 33 counties in the central valley of California, 1945-1982, were compared with the prevalence of household air conditioning and television. Encephalitis rates were negatively associated with television ownership in both cross-sectional and longitudinal analysis. Moreover, individual counties which experienced the most rapid increase in household television ownership had the greatest decline in encephalitis rates. A telephone survey conducted in Kern County revealed that air conditioner and television utilization times corresponded closely to the feeding times of Cx. tarsalis, and respondents indicated a preference to remain indoors during this time because of these appliances. It is concluded that changed behavioral patterns may protect from vector-borne diseases and be complementary to vector control programs.

Air Conditioning↗
PubMed1999

Recombination of hepatitis D virus RNA sequences and its implications.

Recombination between RNA sequences plays a role in the fast evolution of a few viruses. There has been no report on hepatitis D virus (HDV) recombination. In this study, we analyzed genetic recombination of HDV and its possible impact on evolution and clinical course. The aligned HDV sequences allowed us to construct a phylogenetic tree which supported the notion of distinct lineages of HDV. The tree was also used in the analysis of recombination using partial likelihoods assessed through optimization. Nine segments of the HDV genome with significant levels of genetic recombination were detected. Five segments were in the hypervariable region, and four were in the delta-antigen- coding region. None could be found in the well-conserved autocleavage region that is essential for replication. Recombination occurred both between and within types. The results of this study indicated that the remarkable variation in HDV genomic sequences, particularly in the hypervariable region, among different genotypes may at least partly result from multiple episodes of genetic recombination during evolution. Genetic recombination may play a significant role in increasing genetic diversity. Importantly, a genetic recombination (nt 1082-1093) occurred in one of the immunogenic domains of hepatitis delta virus antigen recognized by human and woodchuck antibodies (amino acids 174-195). Genetic recombination also occurred at another segment between nt 1517 and 1535, which was close to one of the predicted T-cell epitopes (amino acids 26-41). In longitudinal analysis of HDV genomes at different time points during chronic infection, novel dominant HDV strains with amino acid changes at these epitopes usually emerged after severe hepatitis attacks. In the comparison of HDV clones during or shortly after flare-up of liver disease, Ka/Ks ratios of > 1 were frequently found, suggesting Darwinian positive selection. Therefore, recombination in these two segments may play an important role for HDV in the evasion of immunity.

Amino Acid Sequence↗
PubMed2001

Changes in left ventricular mass in children and adolescents during chronic dialysis.

Left ventricular hypertrophy (LVH) is an independent risk factor for cardiac mortality in adults with end-stage renal disease (ESRD). It is prevalent in pediatric patients on chronic dialysis. The objectives of this study were to evaluate left ventricular mass (LVM) in children and adolescents at the initiation of dialysis and to assess its changes during chronic dialysis therapy. In this longitudinal analysis, 29 patients aged 4-18 years had an echocardiographic evaluation within 90 days of starting dialysis therapy and a follow-up study at least 6 months later. LVH was defined as LVM index (g/m2.7) > 95th percentile for normal children and adolescents. On the initial echocardiogram 20 of 29 (69%) patients had LVH and 24 patients (83%) had abnormal LV geometry (38% eccentric LVH, 31% concentric LVH, and 14% concentric remodelling). Patients with LVH were more likely to be on antihypertensive medications (16/20) than patients without LVH (3/9) (P = 0.005). Repeat echocardiogram, performed after 10 +/- 3 months on chronic dialysis, showed no significant difference in the mean LVM index (49.6 +/- 17.5 g/m2.7 and 49.7 +/- 16.1 g/m2.7, respectively) or in the prevalence of LVH or LV geometric pattern. However, 14 of 29 patients had a progressive increase in LVM index and 15 patients had regression. Multiple regression analysis showed that baseline LVM index (P = 0.005) and interval change in indexed systolic blood pressure (P = 0.027) were independent predictors for LVM index changes. In summary, LVH and abnormal LV geometry are already prevalent in children and adolescents with renal failure at the time of initiation of dialysis therapy, indicating that LVH develops during the pre-ESRD course. Early intervention to control blood pressure may be an important factor to improve and prevent progression of LVH in pediatric patients with ESRD.

Adolescent↗
PubMed1993

Changes in condom use by gay men.

Cross sectional and longitudinal data on condom use among homosexually active men is presented. Data pertain to two waves of interviewing (1987/8 and 1991) from Project SIGMA, a large longitudinal study of male homosexual behaviour in the light of HIV. Aggregate changes across the time-period indicate an increase in condom use for both insertive and receptive anal intercourse, particularly with casual partners. Condom use is still much more prevalent with casual rather than regular partners. Longitudinal analysis show considerable changes at the individual level, with almost a third of men changing their practices. Half of those decreased their risk behaviours, whilst the other half increased them. Less than 1% used condoms for fellatio in the year preceding the 1991 interview, but 8.3% had used other barriers during sex, primarily for hygiene and fun reasons, rather than as disease prophylaxis. Some implications are drawn for condom promotion and HIV prevention.

Adolescent↗
PubMed2000

Oxygen saturation during the first 24 hours of life.

AIM: To determine normative data for arterial oxygen saturation, measured by pulse oximetry (SpO2), in healthy full term infants throughout their first 24 hours of life. METHODS: Long term recordings of SpO2, pulse waveform, and breathing movements were made on 90 infants. Recordings were analysed for baseline SpO(2), episodes of desaturation (SpO2 </= 80%), apnoeic pauses of >/= four seconds, and periodic apnoea (>/= three apnoeic pauses, each separated by </= 19 breaths). RESULTS: Median baseline SpO(2) was 98. 3% (range 88.7-100). Longitudinal analysis at four hour intervals showed that SpO2 remained stable until 20-24 hours of age, when it became significantly lower (p < 0.03). Episodic desaturations were identified in 23 recordings. Nine prolonged desaturations (SpO2 </= 80% for >/= 20 seconds) were identified in six recordings. Four desaturations fell to </= 60%. Periodic apnoea was identified in 60% of recordings. CONCLUSION: The range of SpO2 during the first 24 hours of life is similar to that found previously during the first month of life. The clinical significance of the prolonged episodes of desaturation observed justifies further investigation.

Apnea↗
PubMed1992

The changing status of hospital libraries 1984 to 1989: characteristics and services in Region 7 of the National Network of Libraries of Medicine.

Economic and political factors have had far-reaching effects on hospital libraries in the last decade, but quantitative evidence of these changes is not readily available. Through periodic evaluation surveys within its multistate region, the Pacific Southwest Regional Medical Library Service, the Regional Medical Library for Region 7 of the National Network of Libraries of Medicine (formerly the Regional Medical Library Network) has monitored hospital library changes over the years. This paper compares data from a 1989 survey with similar information gathered in 1984. Longitudinal analysis was performed on responses from 188 hospitals that responded to both the 1984 and the 1989 survey, as was cross-sectional analysis of all responses from both surveys. Results showed a small decrease in the number of hospitals with separate library collections. Staffing patterns had changed considerably, with a drop of approximately one entire full-time salaried equivalent per library and a decrease in libraries managed by a librarian with an M.L.S. The libraries that provide all of a set of predefined core services and resources decreased from 61% in 1984 to 44% in 1989. Libraries with M.L.S. staff were more likely to have core services than those without professional staff.

Cross-Sectional Studies↗
PubMed1990

Longitudinal study of human papillomavirus infection of the female urogenital tract by in situ hybridization.

The recurrence and/or persistence of human papillomavirus (HPV)-associated lesions constitute a well-recognized clinical problem; yet, few studies have demonstrated and typed the HPV within these recurrence lesions. A patient with a 17-year history of anogenital condylomata presented with an unusual bladder tumor that had histologic features of HPV infection. This prompted a longitudinal analysis of HPV DNA in archival material from these urogenital lesions. Colorimetric in situ hybridization was used to assay for HPV types 6, 11, 16, and 18. Human papillomavirus types 6 and 11 were present throughout the period of follow-up in all the condylomatous lesions, including those identified in the bladder, suggesting a common source of infection and spread. By contrast, HPV type 16 was associated only with the vaginal intraepithelial neoplasia that was identified midway through the period of follow-up, and it was apparently cured by excision of the lesion.

Adult↗
PubMed2000

A longitudinal study of the health impacts of a petroleum refinery.

Emissions from a petroleum refinery in Oakville, Ont., have been the source of longstanding health concerns among residents in the surrounding community. Between 1992 and 1997, the refinery implemented extensive odour reduction measures through improvements in waste water treatment, in sulphur recovery and combustion. In this paper, we present the main findings of a recent longitudinal analysis using data from community health surveys conducted in 1992 and 1997, before and after implementation of the odour reduction plan. The results show a decline in the frequency of odour perception and annoyance by residents whereas the reporting of cardinal and general symptoms among adults and children was virtually unchanged. Odour perception and annoyance were strongly related to symptom reporting in both years supporting the hypothesis that the effect of refinery emissions on residents' health is odour mediated. The findings extend our understanding of the psychosocial basis of symptom reporting in the vicinity of refineries.

Adult↗
PubMed2006

Longitudinal studies of clonally expanded CD8 T cells reveal a repertoire shrinkage predicting mortality and an increased number of dysfunctional cytomegalovirus-specific T cells in the very elderly.

The age-associated decrease in functionality of the human immune system is thought to have a negative impact on the capacity to provide protection against infection, in turn leading to increased incidence of mortality. In a previous longitudinal study of octogenarians, we identified an immune risk phenotype (IRP) in the very elderly defined by an inverted CD4/CD8 ratio, which was associated with increased mortality and persistent CMV infection. In this study, we analyzed the CD8 clonal composition of nonagenarians and middle-aged individuals. An increased number of CD8 T cell clones was observed in the nonagenarians, and was associated with CMV-seropositivity. Surprisingly, CMV-seropositive nonagenarians with the IRP had a significantly lower number of clones compared with non-IRP individuals. The decrease in clone numbers in IRP individuals was associated with shorter survival time. MHC/peptide multimer staining indicated that the frequency of CMV-specific T cells was higher in nonagenarians than in the middle-aged, but the ratio of functionally intact cells was significantly lower. The lowest ratio of functional CMV-specific T cells was found in an IRP individual. A thorough longitudinal analysis of the CMV-specific T cells in nonagenarians showed a stable pattern with respect to frequency, phenotype, and clonal composition. We hypothesize that the number of different CD8 T cell clonal expansions increases as the individual ages, possibly, as a compensatory mechanism to control latent infections, e.g., CMV, but eventually a point is reached where clonal exhaustion leads to shrinkage of the CD8 clonal repertoire, associated with decreased survival.

Aged, 80 and over↗