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P Gann

Publications and source records attributed to P Gann.

12 recordsLinked to original sources
PubMed1997

Mitogenic growth factors in breast fluid obtained from healthy women: evaluation of biological and extraneous sources of variability.

Peptide growth factors (GFs), including epidermal GF (EGF) and transforming GF-alpha (TGF-alpha), are presumed to play an important role in the local regulation of breast cell proliferation. Breast fluid collected by nipple aspiration provides a potential means to assess the concentration of these factors in contact with the ductal epithelium. Although identification of immunoreactive EGF-like GFs in breast fluid has been reported previously, we performed this study to evaluate the sensitivity and reliability of newer RIA methods and to characterize the sources and amounts of both intra- and intersubject variability. We also evaluated the relationship of breast fluid EGF and TGF-alpha levels to each other and to plasma levels of estradiol and progesterone. Breast fluid and plasma samples were obtained two to four times at weekly intervals from 18 healthy, premenopausal women. EGF and TGF-alpha were measured by competitive binding RIA. Both GFs were detected with good precision in all breast fluid samples analyzed, using dilutions as low as 1:100 for EGF (1 microliter) and 1:25 for TGF-alpha (4 microliters). The correlations between the right and left breasts, sampled concurrently, were r = 0.78 (P = 0.003) for EGF and r = 0.89 (P = 0.0001) for TGF-alpha. For both GFs, the variation between women was substantially greater than the variation between breasts or over time in an individual woman, particularly for EGF, for which there were 100-fold differences between women in mean levels. When samples from multiple women were analyzed together, we found no apparent relationships between EGF and TGF-alpha levels or between either GF level and menstrual cycle phase or plasma hormone concentrations. However, in random effects analyses, EGF levels within an individual were significantly associated overall with both TGF-alpha (P = 0.02) and plasma estradiol levels (P = 0.01). These data, which are the first comprehensive results on the feasibility of measuring mitogenic GFs in breast fluid, support the conclusion that women secrete consistent and individually distinct levels of EGF and TGF-alpha and that, in at least some women, EGF secretion in vivo covaries with both TGF-alpha in breast fluid and circulating estradiol.

Adult↗
PubMed1996

Hormone receptor status of breast tumors in black, Hispanic, and non-Hispanic white women. An analysis of 13,239 cases.

BACKGROUND: It has been postulated that different biologic characteristics of a tumor might account for at least a portion of the disparity in breast cancer survival for patients across racial and ethnic groups. The hormone receptor status of breast tumors is one characteristic with prognostic significance. Results of several studies indicate a higher proportion of estrogen receptor negative (ER-) breast tumors among black or Hispanic women compared with non-Hispanic whites. We investigated whether the association between race and ethnicity and the joint combination of ER and progesterone receptor (PR) status was independent of age and other tumor characteristics at diagnosis. METHODS: Relevant data were obtained from 13,239 breast cancer cases identified as part of the 1990 Patient Care Evaluation Study of Breast Cancer. RESULTS: In univariate analysis, the proportions of ER+PR+, ER+PR-, ER-PR+, and ER-PR- tumors among non-Hispanics whites were 59%, 15%, 6%, and 20%, respectively; among Hispanics the proportions were 58%, 12%, 8%, and 22%, respectively; and among blacks the proportions were 44%, 14%, 7%, and 35%, respectively. After controlling for age, tumor size, and histology, using polychotomous logistic regression, these was no difference in hormone-receptor status between Hispanic and non-Hispanic white women. However, ER-PR- tumors were more likely to occur in blacks than in non-Hispanic whites (odds ratio = 1.8, 95% confidence interval = 1.6, 2.1) CONCLUSIONS: The results of this study corroborate differences in hormone-receptor status between non-Hispanic white and black women, but not between Hispanics. Future studies of breast cancer should examine differences in epidemiologic risk factors between blacks and whites stratified on ER/PR status.

Adult↗
PubMed1994

Does maternal prenatal care use predict infant immunization delay?

BACKGROUND: The proportion of infants in the United States adequately immunized with DTP (Diphtheria, Tetanus and Pertussis) vaccine is below other industrialized nations and lowest among infants living in urban areas. At present, predictors of poor immunization are not well developed. In particular, the relationship between prenatal care utilization and childhood vaccination is not clearly defined. METHODS: Using medical record data, we measured associations between prenatal variables and adequacy of immunization (three DTP vaccines by age 10 months) in 163 mother-infant pairs who received prenatal and child care at a neighborhood community health center. RESULTS: At the end of 10 months' follow-up, 29.4% of infants had not received three DTP immunizations. Logistic regression identified the following independent risk factors for immunization delay: multiparity, being an English-speaking Hispanic mother, and failing to attend scheduled prenatal care appointments. In the regression model, interactions also existed between having a high proportion of missed visits to total prenatal visits scheduled (> or = 25%) and receiving social services, with the highest risk existing for women with a high proportion of missed appointments who also received social services, and the lowest for those with < 25% missed appointments who received social services. CONCLUSIONS: Maternal demographics and health care utilization predict infant immunization rates. Use of these variables may permit early identification and case management of mothers of infants at high risk for immunization delay.

Adolescent↗
PubMed1993

Characteristics of primary care office systems as predictors of mammography utilization.

OBJECTIVE: To evaluate the association between primary care office systems and mammography utilization by women older than 50 years. DESIGN: Cross-sectional. SETTING: An independent-practice association health maintenance organization (HMO) in Massachusetts. PARTICIPANTS: One hundred thirty-two primary care practices, representing 321 physicians and 4378 women with at least 12 months of recent, continuous assignment to a practice participating in the HMO. MEASUREMENTS: Practice characteristics and procedures for mammography referral and follow-up were ascertained by interviews of office managers. For each practice, the proportion of women older than 50 years who received a mammogram during their most recent 12-month period of assignment to the practice was calculated. MAIN RESULTS: Forty-five percent of eligible women received a mammogram during their most recent year of assignment to an HMO practice. In a regression model, use of one particular urban mammography center, group practice, and low percentage of Medicaid patients in the practice were each associated with 9% to 12% higher mammography utilization; use of flowsheets and the scheduling of mammograms by the patients themselves were associated with 7% to 9% higher utilization. Smaller, nonsignificant increases were associated with the use of reminders to patients (5%) and the presence of only internists on staff (5%). The model accounted for 51% of the variation in mammography utilization among practices. CONCLUSIONS: Mammography utilization among women older than 50 years, in a population in which cost was not a barrier, was related to specific office characteristics. Features of the mammography center, the process for scheduling mammograms, the use of flowsheets to prompt physicians, and the use of reminders to patients are important.

Aged↗
PubMed1993

Office systems for promoting screening mammography. A survey of primary care practices.

BACKGROUND: Office tracking, scheduling, and reminder systems have been shown to improve utilization of screening mammography, but little is known about the use of these systems by primary care physicians. METHODS: We surveyed 132 primary care and obstetrics and gynecology practices affiliated with an independent practice association model health maintenance organization in central Massachusetts to determine their use of reminder, scheduling, and follow-up systems, and education and counseling services aimed at increasing screening mammography rates. RESULTS: The use of chart flags to remind physicians of a patient's need for mammography screening was reported by 30% of practices. Thirty-one percent reported the use of flow sheets, and 27% reported the use of mail or telephone patient reminders. At least one of these three systems was used by 57% of the practices, whereas 43% reported having none of these three systems. Variations in the use of these office systems were related to specialty type, physician number, and clinical staffing. The majority of practices (77%) reported using written educational materials, and 42% offered prevention counseling with nonphysician staff. Very few offices (8%) reported using mail or telephone reminders for previously scheduled appointments. CONCLUSIONS: Despite the proven effectiveness of reminder systems for screening mammography, many practices do not have a system in place. Promotion of reminder systems in primary care practices could have a substantial impact on mammography utilization.

Ambulatory Care Information Systems↗
PubMed1993

Provider confidence in breast examination.

Many physicians have reported interest in further training in clinical breast examination, and it has been speculated that health care providers may lack confidence in their breast examination skills. At a multisite family practice residency, we surveyed a group of physicians and nurse practitioners about confidence in clinical breast examination. Forty-three percent of respondents reported impairment of the clinical breast examination by lack of confidence in skills, and 50% reported feeling only "somewhat" or "moderately" confident in their clinical breast examination skills. Residents often reported encountering few patients with breast lumps; experience with breast lumps was associated with reported confidence in the clinical breast examination. To improve and maintain breast palpation confidence and skills, residents and practicing physicians need longitudinal educational programs.

Breast Neoplasms↗
PubMed1989

Pregnancy characteristics and outcomes of Cambodian refugees.

This study describes the perinatal characteristics of Cambodian refugees in Massachusetts. Data were abstracted from the records of 452 consecutive pregnancies among Cambodian women and 110 low-income Whites receiving obstetrical services at the same clinic and hospital in Lowell, Massachusetts. Pregnancies of Cambodian women were marked by a higher proportion of older mothers, grand multiparas, previous adverse birth outcomes, and short interpregnancy intervals. We identified maternal anemia (29.9 percent with hemoglobin less than 110 g/L) and inadequate utilization of prenatal care (32.3 percent with first visit in the 3rd trimester) as possible risk factors for the Cambodians. The prevalence of primary cesarean birth was only 6.3 percent in the Cambodians, compared to 15.6 percent in the comparison group, largely due to the infrequent occurrence of prolonged labor among multiparas. Despite the prominence of several risk factors for adverse birth outcomes in this population, major pregnancy complications were less common and the prevalence of low birthweight (6.4 percent) was close to the state average. Logistic regression analysis of risk factors for low birthweight identified young maternal age and short stature as the strongest factors operative in this community. Many of our findings are consistent with a strong cultural emphasis on managing the size of the baby to avoid a difficult labor and delivery.

Adult↗
PubMedDate not supplied

Identification of an in vivo chrysene diol epoxide adduct in human hemoglobin.

Human blood samples were analyzed by fluorescence and mass spectrometry for the presence of polycyclic aromatic hydrocarbon metabolites covalently bound to hemoglobin. Globin was prepared by HCl-acetone precipitation and enzymatically digested. The polycyclic aromatic alcohols generated from ester adducts during digestion were concentrated by monoclonal antibody immunoaffinity chromatography and separated by C-18 HPLC. Analysis of collected fractions by room temperature fluorescence spectroscopy revealed the presence of the anti-tetrahydrotetrols of benzo[a]pyrene and another component possessing a phenanthrene chromophore. Gas chromatographic-mass spectral analysis of the HPLC fractions revealed that the latter compound was r-1,t-2,t-3,c-4-tetrahydroxy-1,2,3,4-tetrahydrochrysene, arising from a hemoglobin-chrysene diol epoxide adduct.

Chromatography, High Pressure Liquid↗
PubMedDate not supplied

Congenital anosmia: detection thresholds for seven odorant classes in hypogonadal and eugonadal patients.

Detection thresholds for a representative from each of seven odorant classes (putrid, pepperminty, ethereal, camphoraceous, pungent, musky, floral) were determined by double-blind smell testing of seven normal males, six normal females, 6 patients with uncomplicated congenital anosmia and 13 patients with the syndrome of congenital anosmia and hypogonadotropic hypogonadism (the Kallmann syndrome, olfactogenital dysplasia). The median detection thresholds did not differ significantly between hypogonadal and eugonadal anosmics for any of the odorants, suggesting that the endocrine deficit does not result from inadequate rhinencephalic input to brain centers controlling gonadotropin release. Phenylethylmethylethylcarbinol (PEMEC), a stable chemical of the floral class, was detecred at very low concentrations (10(-6) to 10(-8) M in water) by all normals tested. Since no patient with congenital anosmia was able to distinguish even undiluted PEMEC from water, we suggest that this compound is the material of choice for convenient, rapid and objective testing of the sense of smell (cranial nerve I).

Adolescent↗