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C Crump

Publications and source records attributed to C Crump.

14 recordsLinked to original sources
PubMed2006

Locating and linking to medical care HIV-positive persons without a history of care: findings from the California Bridge Project.

The California Bridge Project was developed to actively locate out-of-treatment HIV-positive persons and link them to HIV care and treatment services. Three hundred and twenty five clients had never received HIV medical care. Among these clients the average time from HIV diagnosis to contact with project staff was one-and-a-half years. Nearly three-fourth of clients were persons of color and almost half were men who have sex with men (MSM). The project was effective in linking 29.2% of clients to medical care. First contact to linkage required an average of 15.4 client contacts. During these encounters project staff assessed clients' risk behaviors and physical and mental health status and addressed real or perceived barriers to care. Latinos were over two times (adjusted OR = 2.33, p=0.034) and African Americans over three times (adjusted OR = 3.69, p=0.002) more likely than whites to be linked to medical care. Success in linking persons of color to medical care may have been because the majority of project staff were persons of color who were purposely hired with characteristics similar to those of the target population. The Bridge Project demonstrates the challenges faced in attempting to link HIV-positive persons from underserved and marginalized populations to medical care.

Adult↗
PubMed2003

Lung cancer mortality among chromate production workers.

AIMS: To assess mortality in 1997 among 493 former workers of a US chromate production plant employed for at least one year between 1940 and 1972. METHODS: Cohort members were followed for mortality to 31 December 1997. Standardised mortality ratios (SMRs) were calculated for selected cause specific categories of death including lung cancer. Lung cancer mortality was investigated further by calculation of SMRs stratified by year of hire, duration of employment, time since hire, and categories of cumulative exposure to Cr(VI). RESULTS: Including 51 deaths due to lung cancer, 303 deaths occurred. SMRs were significantly increased for all causes combined (SMR = 129), all cancers combined (SMR = 155), and lung cancer (SMR = 241). A trend test showed a strong relation between lung cancer mortality and cumulative hexavalent exposure. Lung cancer mortality was increased for the highest cumulative exposure categories (> or =1.05 to <2.70 mg/m(3)-years, SMR = 365; > or =2.70 to 23 mg/m(3)-years, SMR = 463), but not for the first three exposure groups. Significantly increased SMRs were also found for year of hire before 1960, 20 or more years of exposed employment, and latency of 20 or more years. CONCLUSIONS: The finding of an increased risk of lung cancer mortality associated with Cr(VI) exposure is consistent with previous reports. Stratified analysis of lung cancer mortality by cumulative exposure suggests a possible threshold effect, as risk is significantly increased only at exposure levels over 1.05 mg/m(3)-years. Though a threshold is consistent with published toxicological evidence, this finding must be interpreted cautiously because the data are also consistent with a linear dose response.

Adolescent↗
PubMed2000

Does perchlorate in drinking water affect thyroid function in newborns or school-age children?

Perchlorate is known to suppress thyroid function by inhibiting uptake of iodide by the human thyroid at doses of 200 mg/day or greater. A study was conducted to investigate the potential effects of perchlorate in drinking water on thyroid function in newborns and school-age children. A total of 162 school-age children and 9784 newborns were studied in three proximate cities in northern Chile that have different concentrations of perchlorate in drinking water: Taltal (100 to 120 micrograms/L), Chañaral (5 to 7 micrograms/L), and Antofagasta (non-detectable: < 4 micrograms/L). Among schoolchildren, no difference was found in thyroid-stimulating hormone levels or goiter prevalence among lifelong residents of Taltal or Chañaral compared with those of Antofagasta, after adjusting for age, sex, and urinary iodine. No presumptive cases of congenital hypothyroidism were detected in Taltal or Chañaral; seven cases were detected in Antofagasta. Neonatal thyroid-stimulating hormone levels were significantly lower in Taltal compared with Antofagasta; this is opposite to the known pharmacological effect of perchlorate, and the magnitude of difference did not seem to be clinically significant. These findings do not support the hypothesis that perchlorate in drinking water at concentrations as high as 100 to 120 micrograms/L suppresses thyroid function in newborns or school-age children.

Age Distribution↗
PubMed2000

Glutathione S-transferase theta 1 gene deletion and risk of acute myeloid leukemia.

Individuals with a homozygous deletion of the glutathione S-transferase theta 1 (GSTT1) gene lack GSTT1 enzymatic detoxification of environmental carcinogens by conjugation with glutathione. The GSTT1 gene deletion has been associated with carcinogen-induced chromosomal changes in lymphocytes, and some but not all epidemiological evidence has suggested that the GSTT1 gene deletion may increase susceptibility to myelodysplasia. We conducted a case-control study to test whether individuals with an inherited homozygous deletion of the GSTT1 gene are at increased risk of acute myeloid leukemia (AML). The GSTT1 and GST mu 1 (GSTM1) genotypes were determined by PCR using lymphocyte or bone marrow DNA from 297 AML patients and 152 controls. AML patients were selected from Southwest Oncology Group clinical studies, and controls were identified by random digit dialing in Washington state. No association was observed between the GSTT1 gene deletion and AML [race-adjusted odds ratio (OR), 0.94; 95% confidence interval (CI), 0.55-1.60] or between the GSTM1 gene deletion and AML (race-adjusted OR, 1.26; 95% CI, 0.85-1.88). Patients with secondary AML had a slightly higher prevalence of the GSTT1 and GSTM1 gene deletions compared with de novo AML patients or controls, but this was consistent with chance. Exploratory analyses of AML cytogenetics suggested a few associations, i.e., between the GSTT1 gene deletion and trisomy 8, and between the GSTM1 gene deletion and non-8 trisomies or inv(16). These results do not support the hypothesis that the GSTT1 gene deletion is related to the incidence of AML.

Acute Disease↗
PubMed2000

Ovarian cancer tumor marker behavior in asymptomatic healthy women: implications for screening.

Ovarian cancer screening protocols generally have been limited by inadequate recognition of the normal behavior of tumor markers in women at risk of ovarian cancer. We have characterized the behavior of five serum tumor markers in a large cohort of healthy women and examined the implications for screening. Serial measurements of CA125, HER-2/neu, urinary gonadotropin peptide, lipid-associated sialic acid, and Dianon marker 70/K were obtained during 6 years of follow-up of 1257 healthy women at high risk of ovarian cancer. We analyzed individual-specific tumor marker behavior and explored methods that can exploit this information to develop individual-specific screening rules. These five tumor markers behaved approximately independently. Substantial heterogeneity was observed among women in the behavior of each tumor marker, particularly CA125. Intraclass correlation (ICC), or the proportion of total variability that occurs between individuals, was approximately 0.6 for log-transformed CA125 and urinary gonadotropin peptide, and less than 0.4 for the other markers. This degree of tumor marker heterogeneity among healthy women, and the relative independence of these markers, has important implications for screening and diagnostic tests. Independence of markers results in the clinically useful fact that the combined false positive rate from screening with multiple markers may be estimated by the sum of individual false positive rates. Heterogeneity of tumor marker patterns in healthy women implies that a fixed screening cutoff level is suboptimal to a degree that depends strongly on ICC. Using information on longitudinal measurements and ICC, individual-specific screening rules may be developed with the potential to improve early detection of ovarian cancer.

Adult↗
PubMed1997

A coccidioidomycosis outbreak following the Northridge, Calif, earthquake.

OBJECTIVE: To describe a coccidioidomycosis outbreak in Ventura County following the January 1994 earthquake, centered in Northridge, Calif, and to identify factors that increased the risk for acquiring acute coccidioidomycosis infection. DESIGN: Epidemic investigation, population-based skin test survey, and case-control study. SETTING: Ventura County, California. RESULTS: In Ventura County, between January 24 and March 15, 1994, 203 outbreak-associated coccidioidomycosis cases, including 3 fatalities, were identified (attack rate [AR], 30 cases per 100,000 population). The majority of cases (56%) and the highest AR (114 per 100,000 population) occurred in the town of Simi Valley, a community located at the base of a mountain range that experienced numerous landslides associated with the earthquake. Disease onset for cases peaked 2 weeks after the earthquake. The AR was 2.8 times greater for persons 40 years of age and older than for younger persons (relative risk, 2.8; 95% confidence interval [CI], 2.1-3.7; P<.001). Environmental data indicated that large dust clouds, generated by landslides following the earthquake and strong aftershocks in the Santa Susana Mountains north of Simi Valley, were dispersed into nearby valleys by northeast winds. Simi Valley case-control study data indicated that physically being in a dust cloud (odds ratio, 3.0; 95% CI, 1.6-5.4; P<.001) and time spent in a dust cloud (P<.001) significantly increased the risk for being diagnosed with acute coccidioidomycosis. CONCLUSIONS: Both the location and timing of cases strongly suggest that the coccidioidomycosis outbreak in Ventura County was caused when arthrospores were spread in dust clouds generated by the earthquake. This is the first report of a coccidioidomycosis outbreak following an earthquake. Public and physician awareness, especially in endemic areas following similar dust cloud-generating events, may result in prevention and early recognition of acute coccidioidomycosis.

Acute Disease↗
PubMed1996

Mercury exposure in high school chemistry teachers.

To assess whether high school chemistry teachers had higher urinary mercury concentrations than other high school teachers, 24 high school teachers from nine schools in northeastern Ohio were studied. First morning voided urine samples and air samples from the teachers' classrooms were analyzed for total mercury content by cold vapor atomic absorption. The median adjusted urinary mercury concentration in the 12 chemistry teachers was 4.6 microg/g creatinine (range 2.2-8.2 microg/g creatinine) and it was 6.3 microg/g creatinine in the 12 non-chemistry teachers. All classroom air samples contained mercury levels below detection limits. No evidence was provided that high school chemistry teachers are at increased risk of chronic mercury exposure from their teaching activities compared to other high school teachers.

Adult↗
PubMed1996

The immunogenicity of influenza virus vaccine in solid organ transplant recipients.

We monitored the responses of solid organ transplant recipients (SOTs) to influenza vaccine during consecutive influenza seasons. Standard 1993-1994 trivalent influenza vaccine was given to 68 SOTs and 29 healthy young adults, and hemagglutination-inhibition (HI) antibody titers were determined pre- and post-immunization. Significant rises in geometric mean antibody titers occurred post-immunization for all three antigens in both groups. However, the magnitude of the rise was lower in SOTs (1.5-2.3-fold vs. 8.7-10.4-fold, depending on the antigen) (P < .05), and significantly fewer SOTs had protective HI titers (> or = 1:40) for B/Panama/45/90 antigens (50% of SOTs vs. 76% of healthy subjects) and for A/Texas/36/91 (H1N1) antigens (60% vs. 90%). After exclusion of persons with high preimmunization titers, SOTs had significantly reduced frequencies of > or = 4-fold antibody responses compared with those of healthy subjects (23%-38% vs. 86%-100%) (P < .05 for each antigen). When a series of two injections of standard 1994-1995 vaccine was given to 23 SOTs, there was no significant improvement in vaccine response with the second dose. Some SOTs have deficient responses to inactivated influenza vaccines.

Adult↗
PubMed1990

Employee fitness and wellness programs in the workplace.

Worksite fitness and health promotion programs have grown exponentially in the past 15 years. To examine the impact of these programs, the literature through 1988 was reviewed. In general, fitness and wellness programs result in increased levels of fitness and a reduction in the risk factors for coronary heart disease. Recent research using control groups has found relations between reduction in health care costs, absenteeism, and turnover and implementation of comprehensive health promotion programs. Issues related to participation rates, program implementation, and evaluation are also addressed.

Accidents, Occupational↗
PubMed1988

Percutaneous access devices in calves receiving an artificial heart.

Vegetative endocarditis and thromboembolism are the two leading pathologic findings and causes of death in calves receiving total artificial hearts (TAH). Percutaneous access devices (PAD) for the pneumatic drive lines often become infected and may serve as the nidus of infection of the vegetative lesions. Observations of 80 calves living with TAHs revealed that most infections began at the dorsal surface of the PAD. Chronic skin ulceration or acute, traumatic avulsion can result in PAD separation from the skin and bacterial implantation. Evaluation of 58 necropsy specimens from calves with TAHs demonstrated improper flange positioning in 76% of the PAD and gross infection in 57%. A new implantation technique and design of PAD have resulted in better flange position and less irritation at the skin/device interface. Necropsies of 11 animals with the new PAD have shown a reduction in superficial infections.

Animals↗
PubMed1985

Comparative hematological data from animals implanted with a total artificial heart containing different valves.

A review of animals receiving a TAH with 4 mechanical valves suggests that the least damage to the blood cell components is associated with the BS valve when compared with the MH valve at similar heart rates. Clinical anemia in varying stages was observed in most animals in this study. However, most calves compensated for the increased rate of hemolysis and none required blood transfusions. The BS valve would appear to combine minimal turbulence and mechanical crushing in a physiological setting.

Animals↗
PubMedDate not supplied

Adverse birth outcomes among Mexican-Americans: are US-born women at greater risk than Mexico-born women?

OBJECTIVE: We examined adverse birth outcomes among Mexican-Americans to determine the effect of country of maternal birth, a measure of acculturation. DESIGN: We conducted a retrospective cohort analysis of birth outcomes among 4800 Mexico-born and 4800 US-born Mexican-American women using Washington State birth certificate data from 1989 to 1994. Length of residence at current address was used to help refine our measure of acculturation. RESULTS: US-born women had a slightly increased risk of preterm birth relative to Mexico-born women [relative risk (RR) 1.18, 95% confidence interval (CI) 1.04-1.33]. Among Mexico-born women, the risk of preterm birth increased with greater duration of current residence. CONCLUSIONS: US-born Mexican-American women had a slightly increased risk of preterm birth despite having more adequate prenatal care, more education, and higher socioeconomic indicators. This may be due to acculturation factors, such as earlier pregnancy, loss of social support systems, and increased smoking or alcohol use. Reducing this risk depends on recognition among health care workers and policy-makers of the potential influence of acculturation on health in this population.

Acculturation↗
PubMedDate not supplied

Characteristics of health promotion programs in Federal worksites: findings from the Federal Employee Worksite Project.

PURPOSE: To describe how well-established health promotion programs at selected federal worksites were designed, organized, and implemented and to identify factors related to employee participation. DESIGN: This descriptive study related characteristics of the health promotion program, worksites, and workforce to employee participation and perceptions of program impacts. SETTING: The study was conducted at 10 established federal worksite health promotion programs in various regions of the country. SUBJECTS: A total of 3403 of 5757 federal employees (59%) sampled completed employee surveys. MEASURES: Study data were collected from on-site observations, interviews, focus groups, and employee surveys. RESULTS: Overall, program participation rates were high, and employees reported positive impacts on their health and attitudes toward the agency. Participation in health screening, perceived program convenience, and perceived support by management and others were important determinants of participation and of perceived work-related outcomes. CONCLUSIONS: Although site selection and response rate limit generalizability, the sites evaluated represent a broad cross-section of different types and sizes of agencies. The findings should be relevant in many other settings. Study programs compare favorably with private sector programs. Employees viewed the programs very positively. The most cogent challenge in justifying these, and perhaps other, worksite programs is that most participants already or simultaneously engage in health promotion activities elsewhere "on their own."

Female↗