Biomedical subjects

S B Amini

Publications and source records attributed to S B Amini.

At least 19 recordsLinked to original sources

PubMed1999

Longitudinal changes in glucose metabolism during pregnancy in obese women with normal glucose tolerance and gestational diabetes mellitus.

OBJECTIVE: This study prospectively evaluated the longitudinal changes in insulin sensitivity, insulin response, and endogenous (primarily hepatic) glucose production and suppression during insulin infusion in women with normal glucose tolerance (control) and gestational diabetes mellitus before and during a planned pregnancy. STUDY DESIGN: Eight control subjects and 7 subjects in whom gestational diabetes mellitus developed were evaluated with an oral glucose tolerance test, an intravenous glucose tolerance test, and hyperinsulinemic-euglycemic clamp with infusion of [6,6 (2)H2 ]glucose before conception and at 12 to 14 and 34 to 36 weeks' gestation. Insulin response was estimated as the area under the curve during the intravenous glucose tolerance test. Basal endogenous glucose production was estimated from isotope tracer dilution during steady state with [6,6 (2)H2 ]glucose and suppression during insulin infusion. Insulin sensitivity to glucose was defined as the glucose infusion rate required to maintain euglycemia during steady-state insulin infusion. Body composition was estimated with hydrodensitometry. Data were analyzed with 2-way analysis of variance with repeated measures for 2 groups. RESULTS: There were increases in first-phase (P =.006) and second-phase (P =. 0001) insulin responses in both groups with advancing gestation, but the increase in second-phase response was significantly greater (P =. 02) in the gestational diabetes mellitus group than in the control group. Basal glucose production increased significantly (P =.0001) with advancing gestation, and there was resistance to suppression during insulin infusion in both groups (P =.0001). There was less suppression of endogenous glucose production however, in the gestational diabetes mellitus group than in the control group (P =. 01). Insulin sensitivity decreased with advancing gestation in both groups (P =.0001), and there was lower insulin sensitivity in the gestational diabetes mellitus group than in the control group (P =. 04). Significant decreases in insulin sensitivity with time (P =. 0001) and between groups (P =.03) remained when the data were adjusted for differences in insulin concentration or residual hepatic glucose production. CONCLUSION: Obese women in whom gestational diabetes mellitus develops have a significant increase in insulin response but decreases in insulin sensitivity and suppression of hepatic glucose production during insulin infusion with advancing gestation with respect to a matched control group. These metabolic abnormalities in glucose metabolism are the hallmarks of type 2 diabetes, for which these women are at increased risk in later life.

Adult↗

PubMed1999

The sensitivity of Medicare claims data for case ascertainment of six common cancers.

BACKGROUND: Although Medicare claims data have been used to identify cases of cancer in older Americans, there are few data about their relative sensitivity. OBJECTIVES: To investigate the sensitivity of diagnostic and procedural coding for case ascertainment of breast, colorectal, endometrial, lung, pancreatic, and prostate cancer. SUBJECTS: Three hundred and eighty nine thousand and two hundred and thirty-six patients diagnosed with cancer between 1984 and 1993 resided in one of nine Surveillance Epidemiology and End Results (SEER) areas. MEASURES: The sensitivity of inpatient and Part B diagnostic and cancer-specific procedural codes for case finding were compared with SEER. RESULTS: The sensitivity of inpatient and inpatient plus Part B claims for the corresponding cancer diagnosis was 77.4% and 91.2%, respectively. The sensitivity of inpatient claims alone was highest for colorectal (86.1%) and endometrial (84.1%) cancer and lowest for prostate cancer (63.6%). However, when Part B claims were included, the sensitivity for diagnosis of breast cancer was greater than for other cancers (93.6%). Inpatient claim sensitivity was highest for earlier years of the study, and, because of more complete data and longer follow up, the highest sensitivity of combined inpatient and Part B claims was achieved in the late 1980s or early 1990s. CONCLUSIONS: Medicare claims provide reasonably high sensitivity for the detection of cancer in the elderly, especially if inpatient and Part B claims are combined. Because the study did not measure other dimensions of accuracy, such as specificity and predictive value, the potential costs of including false positive cases need to be assessed.

Aged↗

PubMed1999

The utility of Medicare claims data for measuring cancer stage.

BACKGROUND: The validity of using claims data for measuring tumor stage, one of the most important determinants of choice of therapy and long-term survival, is unknown. OBJECTIVES: To determine the relative accuracy of both inpatient and hospital Outpatient Medicare claims for measuring the stage of disease of six commonly diagnosed cancers. RESEARCH DESIGN: Analysis of a database linking Surveillance, Epidemiology, and End Results (SEER) registry data and Medicare claims in patients aged 65 years with cancer. SUBJECTS: Three hundred twenty thousand, six hundred and thirty seven cases of invasive breast, colorectal, endometrial, lung, pancreatic, and prostate cancers diagnosed between 1984 and 1993. MEASURES: Using SEER files as the "gold standard," concordance with Medicare claims, as well as sensitivity and positive predictive value of coding for each stage was measured. RESULTS: Although Medicare data correctly categorized local, regional, and distant stage tumors in 97%, 33%, and 65%, respectively, the data substantially overestimated the proportion of localized tumors and underestimated the rate of regional stage disease. The highest concordance was observed for breast and colorectal cancer. However, the sensitivity and positive predictive values were never simultaneously 80% within one stage of a specific cancer. The accuracy of coding for stage in Outpatient files was inferior to inpatient data. CONCLUSIONS: With few exceptions, Medicare claims have limited utility as a measure of cancer stage. If tumor registry data are not available, investigators should consider the trade offs in sensitivity and predictive value when considering a study that will use claims data.

Aged↗

PubMed1999

Overexpression of ornithine decarboxylase in prostate cancer and prostatic fluid in humans.

Prostate cancer (PCA), the most commonly diagnosed cancer in males in the United States, is the second leading cause of cancer-related deaths of males in this country. Because of the poor success rate in the treatment of PCA, an intervention at an early stage may reduce the progression of small carcinoma to large metastatic lesion, thereby reducing PCA-related deaths. Concerted efforts are needed to establish mechanism-based approaches to develop: (a) the markers for early detection of the disease as well as toward monitoring the efficacy of treatment(s); and (b) novel chemopreventive strategies against PCA. Using unique samples of pair-matched benign and cancer tissue obtained from the same PCA patient, we showed that ornithine decarboxylase (ODC) activity is significantly (P < 0.001) elevated in PCA (1142 +/- 100; mean +/- SE) than in paired benign tissue (427 +/- 51; mean +/- SE). The immunoblot analysis also showed a significant elevation in the protein expression of ODC in the PCA tissues as compared with the paired benign tissue. Furthermore, our data showed that the ODC activity in the prostatic fluid obtained by a digital rectal massage from the patients with PCA (3847 +/- 162; mean +/- SE) was significantly higher than in the patients with benign prostatic hyperplasia (2742 +/- 167; mean +/- SE) or normal individuals (1244 +/- 67; mean +/- SE). This observation might be of significance because the prostatic fluid could be obtained noninvasively by digital rectal massage. We suggest that ODC could serve as a target for early detection of human PCA as well as for monitoring the efficacy of treatment(s). The development of ODC as a target for novel chemopreventive strategies against PCA is an intriguing possibility.

Biomarkers↗

PubMed1998

Altered expression of RET proto-oncogene product in prostatic intraepithelial neoplasia and prostate cancer.

BACKGROUND: The RET proto-oncogene encodes a protein that belongs to the tyrosine kinase growth factor receptor family. Germline point mutations in RET are found in individuals with multiple endocrine neoplasia (MEN) syndromes, and gene rearrangements have been reported in papillary thyroid cancers. We recently identified transcripts of the RET proto-oncogene in human prostate cancer xenografts and prostate cancer cell lines by means of reverse transcription-polymerase chain reaction analyses. The purpose of this study was to investigate Ret protein expression in human prostate tissue. METHODS: Ret protein expression was evaluated immunohistochemically in formalin-fixed, paraffin-embedded whole-prostate sections. The prostate specimens were obtained from 30 patients with prostate cancer after radical prostatectomies. Ret protein expression was compared in tumor foci and benign prostatic tissue. Medullary thyroid carcinoma tissue associated with an MEN syndrome and papillary thyroid cancer tissue served as positive controls. RESULTS: Ret appeared to be overexpressed in high-grade (histopathologically advanced) prostatic intraepithelial neoplasia (PIN) and prostate cancer when compared with its expression level in benign prostatic secretory epithelium. In addition, there was an apparent increase in Ret protein expression with decreased cellular differentiation, i.e., increasing Gleason pattern. CONCLUSION: Expression of the RET proto-oncogene in benign prostatic epithelium, high-grade PIN, and histopathologically advanced prostate cancer suggests that RET may play a role in the growth of both benign and neoplastic prostate epithelial cells.

Drosophila Proteins↗

PubMed1998

Longitudinal changes in body composition and energy balance in lean women with normal and abnormal glucose tolerance during pregnancy.

OBJECTIVE: The objective of this study was to evaluate the longitudinal changes in energy expenditure and body composition in relationship to alterations in carbohydrate metabolism in women with normal and abnormal glucose metabolism. We hypothesized that women with decreased insulin sensitivity before conception would have less fat accretion and smaller increases in energy expenditure. STUDY DESIGN: Six women with normal glucose tolerance and 10 women with abnormal glucose tolerance were evaluated before conception, and in early (12 to 14 weeks) and late (34 to 36 weeks) gestation. Body composition was estimated by hydrodensitometry, resting energy expenditure, and glucose and fat metabolism by indirect calorimetry, endogenous glucose production by infusion of [6-6 2H2] glucose, and insulin sensitivity using a hyperinsulinemic-euglycemic clamp (40 mU/m2/min). RESULTS: There was a smaller increase in fat mass (1.3 kg [P = .04]) in early pregnancy in women with abnormal glucose tolerance before pregnancy. Indirect calorimetry measured gestational age-related increases in basal oxygen utilization, with or without correction for fat-free mass (VO2, P = .002), resting energy expenditure (expressed in kilocalories, P = .0001), and carbohydrate oxidation (P = .0003). The insulin-mediated elevation in VO2 increased in later gestation VO2 (P = .005), as did resting energy expenditure (P = .0001) and fat oxidation (P = 0.0001). However, there was a decrease in respiratory quotient (P = .0001), carbohydrate oxidation (P = .002), and nonoxidative carbohydrate metabolism (P = .0001) with advancing gestation during insulin infusion. In early pregnancy, changes in fat mass correlated inversely with changes in insulin sensitivity (r= -0.52, P = .04) and changes in basal VO2 correlated inversely with decreases in basal endogenous glucose production (r = -0.74, P = .01). CONCLUSION: In early gestation, the changes in maternal fat mass and basal oxygen consumption are inversely related to the changes in insulin sensitivity. This response in lean women with decreased insulin sensitivity before conception may have survival value by providing a larger amount of available substrate to meet fetoplacental needs during gestation.

Adult↗

PubMed1998

The effect of oral terbutaline on maternal glucose metabolism and energy expenditure in pregnancy.

OBJECTIVE: Terbutaline, a selective beta2-agonist, is a frequently used tocolytic known to affect maternal metabolism. The purpose of this study was to evaluate the effect of oral terbutaline on maternal glucose metabolism and energy expenditure. STUDY DESIGN: Six healthy pregnant women with normal glucose tolerance were evaluated between 30 and 34 weeks' gestation. Oral terbutaline was administered to determine the effects on hepatic glucose production with [6-6(2)H2] glucose tracer, insulin sensitivity (hyperinsulinemic-euglycemic clamp), and energy expenditure (indirect calorimetry). Terbutaline, insulin, and glucagon levels were also obtained. Subjects were randomly assigned to either oral terbutaline 5 mg every 6 hours for 24 hours or no medication. Repeat studies were conducted 1 week apart, each subject serving as her own control. RESULTS: In the basal state terbutaline was associated with a trend toward increased basal glucose levels (81.6 +/- 6.6 vs 93.7 +/- 12.0 mg/dl, p = 0.06) but no significant increase in hepatic glucose production (3.2 +/- 0.3 vs 3.6 +/- 0.4 mg/kg fat-free mass/min, p = 0.23). However, there was a significant increase in basal insulin concentration (17.6 +/- 9.2 vs 25.6 +/- 10.4 microU/ml, p = 0.02). There was a 28% decrease in insulin sensitivity as measured by the glucose infusion rate during the euglycemic clamp plus residual hepatic glucose turnover (5.78 +/- 1.91 vs 4.16 +/- 1.49 mg/kg fat-free mass/min, p = 0.005). Glucagon concentration was significantly decreased both in the basal state (163 +/- 26 vs 144 +/- 27 pg/ml, p = 0.0007) and during the clamp (144 +/- 27 vs 133 +/- 27 pg/ml, p = 0.003). Basal oxygen consumption increased 9% (270 +/- 49 vs 294 +/- 50 ml oxygen/min, p = 0.007) and caloric expenditure 14% (1.32 +/- 0.23 vs 1.50 +/- 0.31 kcal/min, p = 0.025) or 260 kcal/day with terbutaline. CONCLUSION: Decreased peripheral insulin sensitivity, and to a lesser degree increased endogenous glucose production, may represent the pathophysiology of abnormal glucose tolerance observed in many women treated with oral terbutaline. Common side effects such as tremors and tachycardia experienced by many women on a regimen of terbutaline are consistent with our finding of a significant increase in basal energy expenditure.

Adrenergic beta-Agonists↗

PubMed1998

Barriers to adequate delivery of hemodialysis.

Mortality rates among American hemodialysis patients are the highest in the industrialized world. Measures of delivered dialysis (Kt/V) correspond strongly with survival and are estimated to be inadequate in one third of patients. We sought to determine the importance of potential barriers to adequate dialysis, including patient-related and technical factors. Using a cross-sectional study design, we abstracted the charts of 721 randomly selected patients from all 22 chronic hemodialysis units in northeast Ohio. For each of 1,836 treatments provided to these patients, we assessed delivered dialysis (Kt/V) and patient-related factors (ie, hypotension, intradialytic symptoms, and treatment time missed due to noncompliance or transportation problems) and technical factors (ie, dialysis prescription, type of vascular access, clotting, and dialyzer reuse). We used hierarchical regression analysis to determine which potential barriers were independently related to delivered dialysis after adjustment for patient demographic and medical characteristics. Barriers independently related to dialysis delivery (all P values < 0.001) included patient noncompliance, present in 3% of treatments; low dialysis prescription, 14%; use of a catheter for vascular access, 11%; and clotting, 1%. The prevalence of identified barriers varied dramatically across facilities (eg, the prevalence of low dialysis prescription ranged from 0% to 37%, while the prevalence of catheter use ranged from 3% to 28%). In conclusion, patient noncompliance, low dialysis prescription, catheter use, and clotting are the most important barriers to dialysis delivery. Further work is needed to develop interventions to overcome these barriers and to determine the effect of such interventions on dialysis adequacy and patient survival.

Adult↗

PubMed1998

Race and sex differences in long-term survival rates for elderly patients with pulmonary embolism.

OBJECTIVES: The goal of this study was to provide estimates of race- and sex-specific survival rates over a 10-year period for a cohort of 49,752 Medicare patients admitted to the hospital in 1984 with a diagnosis of pulmonary embolism. METHODS: Data were derived from Medicare Provider Analysis and Review Record inpatient claims files and the National Death Index file. RESULTS: For a primary diagnosis of pulmonary embolism, median survival times among Black men and women were 2.5 years and 5.2 years, respectively; for White men and women, the median survival times were 4.3 years and 5.9 years, respectively. Median survival times for Black men and women and White men and women with a secondary diagnosis of pulmonary embolism were 0.4 years, 0.7 years, 0.8 years, and 1.4 years, respectively. Survival rates declined with advancing age. CONCLUSIONS: Overall, survival rates among Blacks were lower than those among Whites, and men had lower survival rates than women. These survival estimates provide new insights into outcomes following pulmonary embolism in hospitalized elderly people.

Aged↗

PubMed1998

Longitudinal changes in pancreatic beta-cell function and metabolic clearance rate of insulin in pregnant women with normal and abnormal glucose tolerance.

OBJECTIVE: To evaluate basal pancreatic beta-cell secretion and suppression during infused insulin and the metabolic clearance rate of insulin in women with normal and abnormal glucose tolerance prior to conception and during pregnancy. RESEARCH DESIGN AND METHODS: Seven women with normal glucose tolerance and nine women with abnormal glucose tolerance during gestation were evaluated prior to conception, in early (12-14 weeks) and late (34-36 weeks) gestation. Basal insulin and C-peptide were measured after an 11-h fast and during the last 40 min of a 2-h hyperinsulinemic-euglycemic clamp at 40 mU.m-2.m-1. Suppression of basal C-peptide was calculated as the steady-state C-peptide/basal C-peptide. The metabolic clearance rate of insulin was calculated by dividing the insulin infusion rate by the steady-state insulin concentration, which was corrected for residual beta-cell secretion. RESULTS: No significant differences were noted in the following parameters between women with normal and abnormal glucose tolerance with advancing gestation: increase in basal insulin (P = 0.20) and C-peptide (P = 0.12), ability of infused insulin to decrease basal C-peptide concentration (P = 0.22), and metabolic clearance rate of insulin (P = 0.76). There was a significant 65% increase in both basal insulin (P = 0.0005) and C-peptide (P = 0.0002) concentrations in all subjects with advancing gestation. There was a significant (P = 0.0001) decrease in the ability of the infused insulin to decrease basal C-peptide concentration. C-peptide as a percentage of the basal was 64% before conception, 74% in early pregnancy, and 108% in late pregnancy. The metabolic clearance rate of insulin significantly (P = 0.0005) increased with advancing gestation: pregravid 442 ml.m-2.min-1, early pregnancy 514 ml.m-2. min-1, and 526 ml.m-2.min-1 in late pregnancy. CONCLUSIONS: Pregnancy is accompanied by progressive alterations in insulin kinetics, which are partly responsible for the hyperinsulinemia of this condition. These alterations are more likely a homeostatic response to the increased physiological insulin resistance of pregnancy.

Adult↗

PubMed1997

Differential growth of fetal tissues during the second half of pregnancy.

OBJECTIVE: Our purpose was to examine the pattern of growth of both fetal lean body mass incorporating bone, brain, and muscle and subcutaneous fat mass during the course of normal pregnancy. We hypothesized that there are detectable differences in the accretion of fat versus lean body mass. STUDY DESIGN: To establish our method we correlated standardized cross-sectional ultrasonographic images of the fetal extremities with anthropometric assessment of neonatal body composition in 25 subjects. Subsequently 36 nonsmoking women with normal prepregnancy body mass index, normal glucose screening results, and no medical or obstetric complications were recruited. We performed 135 ultrasonographic examinations between 19 and 40 weeks' gestation (mean 3.8 scans per fetus, range 2 to 6) at 4-week intervals. Lean body mass measures included biparietal diameter, head circumference, and femur length. Fetal subcutaneous fat and lean body mass were examined both in the mid upper arm and midthigh by standardized cross-sectional images. All neonates were born between 37 and 42 weeks' gestation and had normal birth weight distribution. Stepwise regression analysis established best-fit equations for fetal measurements obtained ultrasonographically. Independent variables included gestational age, maternal age, weight gain in pregnancy, parity, fetal gender, and maternal prepregnancy weight. RESULTS: Fetal bone growth was best described by a second-order quadratic equation demonstrating deceleration with advancing gestational age (p < 0.0001, R2 0.92 to 0.96). A quadratic equation that accelerates with advancing gestation best described lean body mass accretion in the extremities (p < 0.0001, R2 = 0.85 to 0.86). Fetal fat deposition in the extremities was characterized by an accelerating quadratic equation when plotted against gestational age with maternal age and prepregnancy weight contributing significantly (p < 0.0001, R2 = 0.80 to 0.81). CONCLUSION: Consistent with our hypothesis, fetal fat and lean body mass demonstrate unique growth profiles. We speculate that, as a result of an accelerated rate of growth in late gestation, the measurement of fetal fat will provide a more sensitive and specific marker of abnormal fetal growth when compared with index values of lean body mass.

Adipose Tissue↗

PubMed1997

Longitudinal changes in the relationship between body mass index and percent body fat in pregnancy.

OBJECTIVE: To determine the longitudinal relationship between body mass index (BMI) and percent body fat in women before and during pregnancy. METHODS: Twenty-seven healthy, nonobese women were evaluated before conception, in early gestation (12-17 weeks), and in late gestation (33-36 weeks). Height and weight were measured and BMI was calculated. Percent body fat was estimated using hydrodensitometry with correction for residual lung volume. RESULTS: The correlation between BMI and percent body fat before conception was r = 0.693 (P < .005); in early gestation it was r = 0.723 (P < .005) and in late gestation r = 0.633 (P < .005). The mean pregravid BMI was 21.54 and the 95% predictive confidence interval (CI) for percent body fat was 18.2, 26.5%. For the mean BMI of 22.26 in early gestation, the predictive 95% CI for percent body fat was 20.0, 29.0%. In late gestation, the mean BMI was 26.04 with a predictive 95% CI for percent body fat 22.5, 30.8%. CONCLUSION: In nonobese women the correlation between BMI and percent body fat remains significant during pregnancy, although the 95% CI for predicting percent body fat from the mean BMI ranges widely.

Adipose Tissue↗

PubMed1997

Follicular basal cell hyperplasia overlying dermatofibroma.

Follicular basal cell hyperplasia (FBCH) overlying dermatofibroma represents aborted or impeded pilar differentiation. Historically, this hyperplasia has been misinterpreted as basal cell carcinoma. In a large series of dermatofibroma (258 cases), those that contained primitive or malformed follicular structures over the lesion (59 cases) were compared with those without such elements (199 cases). Statistical analysis of various clinicopathologic features showed that FBCH was significantly associated with younger age, trunk location, hypercellular dermatofibroma, loss of a Grenz zone, clear cell hyperplasia, and seborrheic keratosis-like change. There was an inverse correlation between epidermal atrophy, lichen simplex chronicus-like change, and lower extremity location with FBCH. Histologic features favoring a diagnosis of FBCH over basal cell carcinoma are the focal nature and superficial location of the lesion, lack of cytologic atypia and mitoses, recognizable components of hair follicle differentiation, focal condensation of mesenchymal cells around basal cell proliferation, and the association of epidermal hyperplasia. Our findings suggest that FBCH, clear cell hyperplasia, and seborrheic keratosis-like change all represent an expression of follicular differentiation overlying dermatofibroma.

Adult↗

PubMed1997

Neonatal morbidity after elective repeat cesarean section and trial of labor.

OBJECTIVE: To evaluate neonatal outcomes after an elective repeat cesarean section (ERCS) compared with a trial of labor (TOL). POPULATION AND METHOD: All mothers who underwent previous cesarean section and delivered singleton infants at term gestation were identified during a 1-year period. Neonatal outcomes were compared between infants delivered by ERCS (n = 497) and those delivered by TOL (n = 492), and between infants delivered by a successful (n = 336) and a failed (n = 156) TOL. A cohort of mothers and their term infants delivered by routine vaginal delivery were also identified. RESULTS: Infants delivered by ERCS had an increased rate of transient tachypnea compared with infants born by TOL (6% vs 3%). Compared with routine vaginal deliveries, the adjusted odds ratio of developing any respiratory problem after an ERCS was 2.3 (95% confidence interval [CI]: 1.4, 3.8), and for developing transient tachypnea was 2.6 (CI: 1.5, 4.5). In addition, two infants delivered by ERCS developed respiratory distress syndrome. Infants delivered after a TOL had increased rates of suspected and proven sepsis (5% vs 2% and 1% vs 0.1%, respectively). Compared with a successful TOL, the infants delivered by cesarean section after a failed TOL had more neonatal morbidity and had a longer hospital stay (4.8 +/- 2 vs 3.1 +/- 2 days). The odds ratio for developing any respiratory illness after a failed TOL was 2.1 (95% CI: 1.1, 4.1), for suspected sepsis was 4.8 (95% CI: 2.6, 9.0), and for proven sepsis was 19.3 (95% CI: 2.0, 187). Neonatal outcomes after a successful TOL were similar to routine vaginal births. CONCLUSION: Infants born by ERCS are at increased risk for developing respiratory problems compared with those born by TOL. However, TOL is associated with increased rates of suspected and proven sepsis. This appears to be limited to infants delivered by cesarean section after a failed TOL.

Cesarean Section, Repeat↗

PubMed1997

Identification of dysplasia in human colonic aberrant crypt foci.

Aberrant crypt foci (ACF) are grossly invisible putative premalignant lesions in the colon. As dysplasia is considered an important precursor of colon carcinoma, we wanted to determine the presence and severity of dysplasia in human ACF. Fifty ACF from 28 patients were embedded in paraffin, cut serially, and stained with hematoxylin and eosin. Multiple slides from each ACF were evaluated for dysplasia according to a defined set of criteria. Of 50 ACF, 3 (6%) contained focal areas with severe dysplasia, ie, carcinoma in situ, 4 (8%) contained focal areas with moderate dysplasia, and 20 (40%) contained focal areas with mild dysplasia. Twenty-three ACF (46%) contained no detectable dysplasia. In 15 of 27 ACF with dysplasia, less than 50% (eg, 4 of 28, 10 of 54, and 10 of 30 sections) of the sections cut and evaluated from each ACF demonstrated dysplasia. The presence of dysplasia in a large proportion of ACF supports the hypothesis that they may be precarcinomatous.

Adult↗

PubMed1996

CWR22: the first human prostate cancer xenograft with strongly androgen-dependent and relapsed strains both in vivo and in soft agar.

Most patients' prostate cancers respond to androgen deprivation but relapse after periods of several months to years. Only two prostate cancer xenografts, LNCaP and PC-346, have been reported to be responsive to androgen deprivation and to relapse subsequently. Both of these tumors shrink slightly, if at all, and relapse less than 5 weeks after androgen withdrawal. After androgen withdrawal, the human primary prostate cancer xenograft CWR22 regresses markedly, and prostate-specific antigen (PSA) falls up to 3000-fold in the blood of mice. PSA usually returns to normal. In some animals, the tumor relapses and is then designated CWR22R. In these animals, PSA starts to rise approximately 2-7 months, and tumor begins to grow 3-10 months after castration. Animals with CWR22 need to be euthanized because of large tumors 6-12 weeks after the transplantation of CWR22. Androgen withdrawal prolongs life approximately 3-4-fold.

Agar↗

PubMed1996

Births to teenagers: trends and obstetric outcomes.

OBJECTIVE: To compare the trends and obstetric outcomes of pregnancy in teenage women with those of adult women. METHODS: We analyzed a 19-year (1975-1993) computerized perinatal data base with data on 69,096 births collected prospectively from a single inner-city tertiary medical center. RESULTS: Of all the births, 1875, (2.7%) were to teenagers 12-15 years old and 17,359 (25.3%) were to teenagers 16-19 years old. Over the study period, the number and proportion of births to teenagers of both age groups declined (P < .001 in both cases). The proportions of teenagers 12-15 and 16-19 years old were highest among blacks (4.1% and 28.1%, respectively), followed by Hispanics (2.4%, 24.7%) and whites (1.6%, 23.1%). More than 95% of teenagers had no private health insurance coverage (staff), significantly higher than the 81.6% of mothers aged 20 years or older (P < .001). More than 8.1% of teenagers 12-15 years old had two or fewer prenatal care visits, significantly higher than 6.8% for teenagers 16-19 years old and 7.1% for adults (P < .001). The average gestational age and birth weight were significantly lower for teenagers 12-15 years old compared with those 16-19 years old and adults. Patients 16-19 years of age had longer gestational age and higher birth weight than the adults. The proportion of primary cesarean deliveries among teenagers 12-15 years old was 11.6%, significantly higher than 9.4% for those 16-19 years old and 10.2% for adults (P < .001). CONCLUSION: On average, females 16-19 years old had better obstetric outcomes than adults, whereas obstetric outcomes for those 12-15 years old were worse than for adults. Therefore, all teenagers should not be grouped together when their obstetric outcomes are compared with those of adults.

Adolescent↗

PubMed1996

A SAS macro for stepwise correlated binary regression.

Several regression methods have been proposed for the analysis of correlated binary data, but none deals with the selection of covariates when there exist a large number of potentially relevant covariates. We present a SAS macro based on a stepwise selection procedure for the analysis of correlated binary data. Using regression methods based on generalized estimating equations originally proposed by Liang and Zeger and extended by Prentice, we describe a score test for forward selection, a Wald's test for backward elimination, and a test for model adequacy based on generalized scores. The methodology and the accompanying computer macro program written in SAS IML are illustrated with data from a prospective study of functional decline in the activities of daily living in a group of elderly patients.

Activities of Daily Living↗