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Biomedical subjects

S W Jordan

Publications and source records attributed to S W Jordan.

At least 19 recordsLinked to original sources
PubMed1996

Decreasing rates of cervical cancer among American Indians and Hispanics in New Mexico (United States).

Minority women in New Mexico (United States)--including American Indian and Hispanic women--have shown disproportionately high incidence rates of invasive cervical cancer during the 1960s and 1970s. Several public health programs in New Mexico were directed toward early detection of cervical cellular abnormalities, particularly targeting the state's minority women. To evaluate the effectiveness of these programs, we examined the New Mexico Surveillance, Epidemiology, and End Results (SEER) data collected from 1969-92, and calculated average annual, age-specific, and age-adjusted incidence rates by ethnic group (American Indian, Hispanic, and non-Hispanic White) for five-year time intervals. We also calculated age-adjusted mortality rates for cervical cancer in the same ethnic groups using state vital records. Age-adjusted incidence rates for invasive cervical cancer show substantial temporal decreases, especially for minority women in the state. The age-adjusted incidence rate decreased by 66 percent, from 30.3 to 10.3 per 100,000 for American Indian women, and by 61 percent, from 26.1 to 10.2 per 100,000 for Hispanic women. A stage shift to earlier stages of cervical neoplasia occurred over the study period, with a substantially higher proportion of in situ compared with invasive cancers diagnosed in the most recent cf the most remote time period. The ratio of incidence rates of in situ to invasive cancers changed dramatically for both American Indian and Hispanic women. Cervical cancer mortality rates decreased steadily among Hispanic women from 1958 to 1992; the decrease among American Indian women was less stable and fluctuated due to small numbers. Ongoing targeted screening programs should help to reduce cervical cancer incidence and mortality further in New Mexico.

Adult↗
PubMed1996

Detection of trisomy 7 in nonmalignant bronchial epithelium from lung cancer patients and individuals at risk for lung cancer.

Early identification and subsequent intervention are needed to decrease the high mortality rate associated with lung cancer. The examination of bronchial epithelium for genetic changes could be a valuable approach to identify individuals at greatest risk. The purpose of this investigation was to assay cells recovered from nonmalignant bronchial epithelium by fluorescence in situ hybridization for trisomy of chromosome 7, an alteration common in non-small cell lung cancer. Bronchial epithelium was collected during bronchoscopy from 16 cigarette smokers undergoing clinical evaluation for possible lung cancer and from seven individuals with a prior history of underground uranium mining. Normal bronchial epithelium was obtained from individuals without a prior history of smoking (never smokers). Bronchial cells were collected from a segmental bronchus in up to four different lung lobes for cytology and tissue culture. Twelve of 16 smokers were diagnosed with lung cancer. Cytological changes found in bronchial epithelium included squamous metaplasia, hyperplasia, and atypical glandular cells. These changes were present in 33, 12, and 47% of sites from lung cancer patients, smokers, and former uranium miners, respectively. Less than 10% of cells recovered from the diagnostic brush had cytological changes, and in several cases, these changes were present within different lobes from the same patient. Background frequencies for trisomy 7 were 1.4 +/- 0.3% in bronchial epithelial cells from never smokers. Eighteen of 42 bronchial sites from lung cancer patients showed significantly elevated frequencies of trisomy 7 compared to never smoker controls. Six of the sites positive for trisomy 7 also contained cytological abnormalities. Trisomy 7 was found in six of seven patients diagnosed with squamous cell carcinoma, one of one patient with adenosquamous cell carcinoma, but in only one of four patients with adenocarcinoma. A significant increase in trisomy 7 frequency was detected in cytologically normal bronchial epithelium collected from four sites in one cancer-free smoker, whereas epithelium from the other smokers did not contain this chromosome abnormality. Finally, trisomy 7 was observed in almost half of the former uranium miners; three of seven sites positive for trisomy 7 also exhibited hyperplasia. Two of the former uranium miners who were positive for trisomy 7 developed squamous cell carcinoma 2 years after collection of bronchial cells. To determine whether the increased frequency of trisomy 7 reflects generalized aneuploidy or specific chromosomal duplication, a subgroup of samples was evaluated for trisomy of chromosome 2; the frequency was not elevated in any of the cases as compared with controls. The studies described in this report are the first to detect and quantify the presence of trisomy 7 in subjects at risk for lung cancer. These results also demonstrate the ability to detect genetic changes in cytologically normal cells, suggesting that molecular analyses may enhance the power for detecting premalignant changes in bronchial epithelium in high-risk individuals.

Aged↗
PubMed1994

Sexually transmitted diseases and other risk factors for cervical dysplasia among southwestern Hispanic and non-Hispanic white women.

OBJECTIVE: To assess risk factors for high-grade cervical dysplasia among southwestern Hispanic and non-Hispanic white women. DESIGN: Clinic-based case-control study. SETTING: University-affiliated gynecology clinics. SUBJECTS: Cases were Hispanic and non-Hispanic white women with biopsy-proven high-grade cervical dysplasia (n = 201). Controls were Hispanic and non-Hispanic white women from the same clinics with normal cervical epithelium (n = 337). METHODS: Study design included interviews focused on histories of sexually transmitted diseases, sexual behavior, reproductive histories, hygienic practices, contraceptive use, cigarette smoking, and diet. Laboratory studies included bacterial and protozoal cultures of the cervix; hybridization tests to identify human papillomavirus (HPV) genome with commercial (ViraPap and ViraType) and polymerase chain reaction-based assays; and serum antibody tests for herpes simplex virus, Chlamydia trachomatis, syphilis, hepatitis B, and hepatitis C. RESULTS: For both ethnic groups combined, after adjustment for ethnicity, age, and sexual behavior, the strongest risks for cervical dysplasia were associated with cervical HPV infection as identified by ViraPap (odds ratio [OR], 12.8; 95% confidence interval [CI], 8.2 to 20.0) or with polymerase chain reaction (OR, 20.8; 95% CI, 10.8 to 40.2). Other factors associated with dysplasia included cigarette smoking at the time of diagnosis (OR, 1.8; 95% CI, 1.2 to 2.8); low income (OR, 2.2; 95% CI, 1.2 to 4.0); low educational level (OR, 6.2; 95% CI, 3.4 to 11.1); history of any sexually transmitted disease (OR, 1.9; 95% CI, 1.3 to 2.7); and seroprevalence of antibodies to hepatitis B (OR, 1.8; 95% CI, 0.9 to 3.5). For Hispanic women, HPV 16/18 identified by ViraType was strongly associated with cervical dysplasia (OR, 171.0; 95% CI, 22.8 to 1280.5). Antibodies to herpes simplex virus type 2 were not associated with dysplasia in Hispanic women but were significantly associated with dysplasia among non-Hispanic whites. Risks associated with cigarette smoking also varied by ethnic group. CONCLUSIONS: The strongest risk factor associated with high-grade cervical dysplasia among clinic attendees was HPV infection. Although most of the risk factors we examined showed similar associations for dysplasia for both ethnic groups, our data suggest that several different risk factors may be relevant to the development of cervical dysplasia in Hispanics compared with non-Hispanic whites who attend the same clinics.

Adolescent↗
PubMed1994

Contraceptive and reproductive risks for cervical dysplasia in southwestern Hispanic and non-Hispanic white women.

BACKGROUND: Various contraceptive practices and reproductive factors have been associated with cervical neoplasia in case-control studies worldwide. METHODS: To investigate contraceptive and reproductive risk factors associated with high-grade cervical dysplasia in southwestern Hispanic and non-Hispanic white women, we carried out a clinic-based case-control study among university-affiliated clinic attendees. RESULTS: Oral contraceptive use ever (odds ratio [OR] = 0.4, 95% confidence interval [CI]: 0.2-0.9) and past diaphragm use (OR = 0.3, 95% CI: 0.1-0.8) were protective for dysplasia in analyses adjusted for age, ethnicity, sexual behaviour, and for cervical papillomavirus (HPV) infection. After further adjustment for Pap smear screening interval, oral contraceptive use ever remained protective for dysplasia. Vaginal deliveries were strongly associated with dysplasia with > 2 vaginal deliveries associated with a 3.9-fold increase in risk after adjustment for age, ethnicity, sexual behaviour, and HPV infection. Using logistic regression models to simultaneously control for effects of multiple factors as potentially related to cervical dysplasia, we found low educational attainment, cervical HPV infection, cigarette smoking, history of any sexually transmitted disease, and having one or more vaginal deliveries to be associated with dysplasia; oral contraceptive use and past diaphragm use also remained protective for high-grade cervical dysplasia in these regression analyses. CONCLUSIONS: The data suggest that use of oral contraceptives (ever) and past diaphragm use are protective for high-grade cervical dysplasia among Hispanic and non-Hispanic white women in New Mexico. The clinic-based perspective of this research (versus population-based studies) may help explain some of these findings.

Case-Control Studies↗
PubMed1994

Cigarette smoking and other risk factors for cervical dysplasia in southwestern Hispanic and non-Hispanic white women.

To assess smoking-related and other risk factors for high-grade cervical dysplasia in southwestern Hispanic and non-Hispanic white women in New Mexico, we conducted a clinic-based case-control study among attendees at university-affiliated gynecology clinics. We collected data on cigarette use, sexual behavior, past and current sexually transmitted diseases, hygienic practices, contraception, and diet. For both ethnic groups combined, after adjustment for the effects of human papillomavirus, sexual behavior, and other risk factors, cigarette smoking at the time of diagnosis was associated with high-grade dysplasia (odds ratio, 1.7; 95% confidence limits, 1.0-2.8). In contrast, former smoking was not associated with cervical dysplasia (odds ratio 0.9; 95% confidence limits, 0.5-1.5). Analyses showed dose-response relationships for the amount of cigarettes smoked per day and for cumulative exposure (pack-years of use) in association with cervical dysplasia. Although our study lacked the power to show statistically significant ethnic differences in smoking-related risks for dysplasia, smoking at the time of diagnosis, high pack-years of use, and smoking at the time of menarche were associated with dysplasia only for non-Hispanic white versus Hispanic women. Our data support hypotheses that implicate cigarette use as an etiological factor in the development of high-grade cervical dysplasia and suggest ethnic differences in risks for dysplasia among women attending the same clinics.

Adolescent↗
PubMed1994

Obesity decreases hepatic glutathione concentrations and markedly potentiates allyl alcohol-induced periportal necrosis in the overfed rat.

Liver biopsies from 9 out of every 10 obese individuals exhibit pathological changes of unknown aetiology and 3 out of every 10 reflect severe injury in the form of periportal fibrosis. To examine the hypothesis that excessive fibrosis in obesity arises in part from a predisposition to injury of the liver by drugs and xenobiotics, we administered 5, 10 and 25 mg/kg doses of the model periportal hepatotoxin, allyl alcohol, to obese Sprague-Dawley rats and age-matched non-obese controls. Alanine aminotransferase activity (ALT) in plasma was ten-fold more elevated in obese animals than in non-obese animals given the 25 mg/kg dose (P < 0.05). On fitting the ALT results to a non-linear, parametric model by iterative non-linear least squares regression, we found that the slope of the log dose ALT curve was similar for obese and non-obese rats. However, the minimum dose required to produce elevated ALT (DMIN) was 50% lower for obese animals (DMIN 6.47 +/- 2.75 vs. 13.3 +/- 0.96 mg allyl alcohol; P < 0.05). In a subsequent experiment, allyl alcohol was administered to obese rats based on ideal body weight, which is defined as the mean total body weight of an age-matched non-obese animal. With this dosing normalization, the 25 mg/kg ideal body weight doses translated to administration of a fixed dose of 13.5 mg allyl alcohol to obese rats. Obese rats treated in this fashion exhibited more severe necrosis in the periportal zone (median necrosis score 2 versus 0-1, P < 0.05) and increased mortality over controls (44% versus 0%; P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

1-Propanol↗
PubMed1991

Cervical papillomavirus infection and cervical dysplasia in Hispanic, Native American, and non-Hispanic white women in New Mexico.

BACKGROUND: Human papillomavirus infections of the cervix are found with varying frequencies in different populations worldwide, and have been associated with cervical cytologic abnormalities. METHODS: We studied 1,603 randomly selected Hispanic, Native American, and non-Hispanic White women in New Mexico to determine the prevalence of cervical HPV infection in these ethnic groups, and its association with Pap smear abnormalities, using a new commercial dot-blot hybridization assay. RESULTS: Nine percent of all women screened had evidence of cervical HPV infection (13.7% of non-Hispanic White women, 9.7% of Hispanics, and 6.6% of Native American women). Prevalence was higher in younger women ages 14-19 years than in older age groups. Over half of women with cervical HPV infection (n = 145) had normal Pap smears. The proportion of infected women increased among those with more advanced cytopathologic abnormalities; 5.6 percent with normal Pap smears had cervical HPV vs 66.7 percent with moderate-severe dysplasia. CONCLUSIONS: Cervical HPV infection is common among New Mexico clinic attendees, varies in prevalence among the three major ethnic groups, and is strongly associated with cervical cytopathologic abnormalities.

Adolescent↗
PubMed1989

Quantitative morphology of late renal radiation injury.

Late radiation injury manifests itself in all morphologic compartments of the kidney, but loss of cell mass is most significant in the proximal convoluted tubules. Development of an end stage or nonfunctional kidney requires 12 or more months after single fraction X ray exposures of about 12 Gy (2, 5, 13) and is associated with marked morphologic alterations of renal tubules. Radiation induced changes were studied at 6 months after irradiation, a time interval when histological alterations appear minor, but in previous studies were shown to correlate with the later end stage alterations (5, 8, 9). Renal alterations were graded objectively based on renal weight, variation in size of tubule cell nuclei, and glomerular nuclear volume fraction. Irradiation was associated with loss of renal weight, increased variability of tubule nuclear size, and previously unappreciated changes in glomerular nuclear volume fraction. A classification index derived from a weighted combination of renal weight ratio and tubule cell nuclear variability correlates with radiation dose and with previously established subjective histologic grading of renal damage, and allows objective comparisons of various fractionation schedules.

Animals↗
PubMed1988

The cytogenetic and hepatotoxic effects of dioxin on mouse liver cells.

The cytogenetic and hepatotoxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on mouse liver cells were investigated. Male C57BL/6J strain mice, which have TCDD receptors, were given single intraperitoneal injections of 25, 37.5, 75 and 150 micrograms of TCDD/kg body weight or corn oil carrier alone. Two-thirds hepatectomies were carried out at 1 or 7 days after injection and chromosomal aberrations and mitotic indexes of the regenerating hepatocytes were scored 54 hr after hepatectomy. Liver sections from additional intact mice were studied for TCDD-hepatotoxicity at 1, 7 and 30 days after injection. The three high doses of TCDD caused hepatotoxicity with necrosis of liver cells and focal architectural collapse by 30 days after injection. No evidence was obtained of an increase in the frequency of chromosomal structural aberrations at doses that allowed sufficient mitotic activity for cytogenetic evaluation. We conclude that TCDD is not a clastogen for mouse hepatocytes, although high doses cause marked hepatocellular necrosis.

Animals↗
PubMed1988

Video-based image collection for quantitative histopathology.

Obtaining histologic images for computer-based morphometric analysis is associated with a number of standardization problems, which must be solved if reproducible data collection is expected. These problems include tissue processing, sectioning and staining, standardizing and calibrating the video camera and determining the appropriate sampling rate (pixels/micron). Suggested solutions for these problems are presented for a specific image analysis system, but are applicable to other systems with similar capabilities. Biologic variability is not eliminated by computer-assisted analysis, so it is important to minimize data-collection artifacts by parallel processing of experimental and control material, as in other investigative work.

Animals↗
PubMed1985

Hepatotoxic doses of dioxin do not damage mouse bone marrow chromosomes.

We report on a study of the cytogenetic and hepatotoxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Mice of the C57B1/6J (with high-affinity TCDD receptor) or DBA/2J (with low-affinity TCDD receptor) strains were given single intraperitoneal injections of 50, 100 or 150 micrograms of TCDD/kg body weight. At various times (8-48 h) after injection, we examined bone marrow cells for cytogenetic effects by performing structural aberration, sister-chromatid exchange, and micronucleus tests. 1 month after exposure, liver sections were studied for hepatotoxic effects. We found no evidence of chromosome damage by TCDD given in doses that cause liver damage in both strains of mice.

Animals↗
PubMed1985

Fraction size, dose and time dependence of X ray induced late renal injury.

Histologic quantitation of renal radiation injury based on an intact mouse model correlates well with loss of renal mass, as measured by the ratio of right to left renal weight, radiation dose, and time after irradiation. Use of the radiation dose at which 50% of animals show renal tubular changes of a specified grade (ED50), allows comparison of 1, 5 and 15 fraction exposures. The X-ray dose necessary to effect significant injury (Grade 3 change) by six months after irradiation (ED50) was 11.6, 25.7, and 44.0 Gy for single, 5, and 15 fractions, respectively. Isoeffect plots of total radiation dose as a function of fraction number are linear on logarithmic coordinates, indicating that this relationship followed a power function. When plotted as inverse total dose versus dose per fraction, the six month post-irradiation data were linear, but the 12 month data were not. Lack of linearity is not in agreement with the multi-fraction isoeffect linear quadratic model.

Animals↗
PubMed1984

Meningeal carcinomatosis from an ovarian primary: a clinicopathologic study.

Meningeal carcinomatosis due to primary ovarian carcinoma is an uncommon metastasis that presents difficult problems in diagnosis and management of patients known to have this disease. There is evidence that extended survival due to advances in treatment of ovarian carcinoma has improved our ability to diagnose meningeal carcinomatosis of this tumor more often. Herein the first case of meningeal metastasis of primary ovarian cancer with cytologic and postmortem examination is discussed.

Adenocarcinoma↗
PubMed1982

The pathogenesis of radiation injury in complex tissues: an overview of problems and probes.

The evaluation of radiation injury in complex organs has tended to lag behind comparable areas of investigative interest. This observation is somewhat surprising in view of the increased use of radiotherapy as a primary or adjuvant mode of therapy for malignant disease. In part, this problem appears to relate to the difficulty of identifying and quantifying the morphologic consequences of radiation injury in complex organs, in which the various component tissues exhibit a broad spectrum of radiosensitivities. Two approaches have been employed to address this problem: (1) utilization of sophisticated probes to evaluate the functional and morphologic sequelae of radiation injury and (2) segmentation of complex tissues into their component parts, which are then evaluated individually. Both approaches are illustrated in the papers presented in this issue. The purpose of this overview is to call attention to some of the attendant difficulties of the former approach, as seen in an ongoing investigative program concerned with radiation injury of the kidney.

Animals↗