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Biomedical subjects

P M Meyer

Publications and source records attributed to P M Meyer.

At least 19 recordsLinked to original sources
PubMed2006

An approach to identify dairy cows being responsive to recombinant bovine somatotropin.

Forty-eight primiparous and pregnant Holstein cows at 202 (+/-59) days in milk and average daily milk production (DMP) of 22 (+/-5.3) kg at the beginning of the trial were used to study the possibility of identifying animals that are more responsive to recombinant bovine somatotropin (rbST). Animals were housed in free-stall barns, milked three times a day and fed a total mixed ration. Animals were injected with one dose (500 mg each) of rbST every 21 days during a 105-day total period (five doses in all). Daily milk production was recorded to measure average apparent response (AAR) and peak of apparent response (PAR). Average apparent response was defined as the average increase in milk production, expressed as kilogram per cow per day, for days 0-18 after dosing, as compared to the average production calculated for days -1, -2, -3, 19, 20 and 21 after dosing. Peak of apparent response was calculated as the increase in milk production for each day from 0 to 18 days after dosing as compared to the average production for days -1, -2 and -3. There was a positive linear correlation (r = 0.608; p = 0.0001) between AAR for the first 21 days and AAR for the total 105-day period (AATR). A correlation coefficient was calculated between each individual PAR value and AATR. The highest correlation coefficient (r = 0.511; p = 0.0002) was observed for days 8, 9 and 10, and therefore these days were considered the best estimates for calculating AAR when DMP records are not available. Also, high somatic cells count had a negative impact on milk yield response to treatment (p = 0.0162).

Animals↗
PubMed2003

A population-based longitudinal study of cognitive functioning in the menopausal transition.

BACKGROUND: No longitudinal studies have tracked cognitive performance through the menopausal transition and thus the impact of the transition on cognition, independent of aging, is not known. The authors hypothesized that a decline in cognitive functioning occurs as women progress through the menopausal transition, independent of age, educational level, family income, ethnicity, and baseline self-perceived health. METHOD: The authors began a population-based, longitudinal study in January 1996 with yearly follow-up interviews. This report includes follow-up through November 2001. The authors randomly selected African American and white women from a census of two contiguous Chicago communities. After screening for eligibility (age 42 to 52 years, premenopausal or early perimenopausal, no exogenous hormone use in the past 3 months, and no hysterectomy), 868 agreed to participate. Women who became pregnant, had a hysterectomy, or began using hormones were censored from that time onward. This study reports on 803 women for whom cognitive assessments were available. The authors assessed working memory (Digit Span Backward) and perceptual speed (Symbol Digit Modalities Test). RESULTS: Contrary to the hypothesis, the authors found small but significant increases over time during the premenopausal and perimenopausal phases. This trend was not accounted for by chronological age, education, family income, ethnicity, or baseline self-perceived health. CONCLUSIONS: Transition through menopause is not accompanied by a decline in working memory and perceptual speed.

Adult↗
PubMed2001

Biopsy correlates of abnormal cervical cytology classified using the Bethesda system.

OBJECTIVE: The goal of this study was to determine the colposcopic findings underlying cytologic abnormalities classified according to the Bethesda system. METHODS: Women undergoing colposcopy for abnormal cytology at an urban teaching hospital between July 1, 1996 and December 31, 1999 had Papanicolaou smears repeated. Results were compared both with biopsy histology and with the worst histology reported after 8-26 months of follow-up. kappa statistics and Spearman's rho were calculated to determine the degree of agreement. RESULTS: Colposcopy was performed for 2263 (94%) women. Referral and repeat Pap smears were reported identically in 493 (25%) of the 1962 women with results for both. No AGUS (atypical glandular cells of uncertain significance) smears were confirmed on repeat smear, and after excluding AGUS, agreement within one grade was found in 1305 of 1854 (70%). Among the 1842 women with squamous cytologic abnormalities, biopsy revealed a lesion more severe than that suggested by referral cytology in 577 (31%) and a less severe lesion in 648 (35%); exact correspondence was found in only 646 (35%). Of 317 women with ASCUS (atypical squamous cells of uncertain significance) on referral Pap smear, a negative repeat smear, and a specific biopsy result, 95 (30%) had true negative histology, while 148 (47%) had condyloma, 56 (18%) had cervical intraepithelial neoplasia (CIN) 1, 8 (3%) had CIN 2, 10 (3%) had CIN 3, and none had cancer. Comparison of repeat smear and colposcopic biopsy yielded a kappa statistic of 0.16. CONCLUSIONS: Cytology classified according to the Bethesda system does not accurately predict histologic diagnosis.

Adolescent↗
PubMed2001

Psychologic distress and natural menopause: a multiethnic community study.

OBJECTIVES: This study examined the association between psychologic distress and natural menopause in a community sample of African American, White, Chinese, Hispanic, and Japanese women participating in a national women's health study. METHODS: A cohort of 16,065 women aged 40 to 55 years provided information on menstrual regularity in the previous year, psychosocial factors, health, and somatic-psychologic symptoms. Psychologic distress was defined as feeling tense, depressed, and irritable in the previous 2 weeks. RESULTS: Rates of psychologic distress were highest in early perimenopause (28.9%) and lowest in premenopause (20.9%) and postmenopause (22%). In comparison with premenopausal women, early perimenopausal women were at a greater risk of distress, with and without adjustment for vasomotor and sleep symptoms and covariates. Odds of distress were significantly higher for Whites than for the other racial/ethnic groups. CONCLUSIONS: Psychologic distress is associated with irregular menses in midlife. It is important to determine whether distress is linked to alterations in hormone levels and to what extent a mood-hormone relationship may be influenced by socioeconomic and cultural factors.

Adult↗
PubMed2000

Negative T waves shortly after ST-elevation acute myocardial infarction are a powerful marker for improved survival rate.

BACKGROUND: Recent studies have reported that negative T waves in the setting of acute coronary events are associated with Thrombolysis In Myocardial Infarction flow grade 3 in the infarct-related artery and with improved parameters of ventricular function rather than with ischemia. METHODS: Patients enrolled in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO-I) angiographic substudy (ie, patients with acute infarction randomly assigned to one of 4 thrombolytic regimens who then underwent coronary angiography) were included in this study if they survived at least 24 hours and had no confounding electrocardiographic factors (n = 1505). RESULTS: More patients had negative T waves develop (NT group, n = 938 [62%]) than not (PT group, n = 567 [38%]). Peak creatine kinase MB, time to thrombolysis, and randomization to accelerated alteplase were no different between the groups. Thirty days after admission, 12 patients in the NT group had died versus 25 patients in the PT group (1.3% vs. 4.4%; P <.001; odds ratio for negative T waves 0.28; 95% confidence interval 0.14-0.56). The difference persisted when only patients who survived at least 3 days were analyzed. After adjusting for relevant covariates (including presence of new Q waves in the follow-up electrocardiogram), negative T waves were an independent predictor for survival (P =. 007; odds ratio for negative T waves 0.38; 95% confidence interval 0. 18-0.78). Patients in the NT group were 35% more likely to have achieved patency of the infarct-related artery, although this difference was not statistically significant. CONCLUSIONS: Negative T waves shortly after acute myocardial infarction treated with thrombolysis were markers for improved 30-day survival rate. This finding merits prospective testing.

Adult↗
PubMed1999

Predicting compliance with follow-up recommendations after colposcopy among indigent urban women.

OBJECTIVE: To determine correlates of compliance with follow-up recommendations after colposcopy. METHODS: Between October 1, 1992, and June 30, 1997, management recommendations were made to 451 consecutive women who attended a resident colposcopy clinic. Compliance was determined after 8-12 months. Correlates of compliance were assessed by univariate and multivariate analyses. RESULTS: Recommendations included repeat cytology in 6 months for 252 women, loop excision for 114, conization for 27, repeat colposcopy for 51, other for three, and not recorded for four. Rates of ever complying were 81% for loop excision, 85% for conization, 62% for repeat colposcopy, and 36% for repeat cytology. In multivariate analysis, the only significant predictors of compliance were history of genital herpes simplex infection (odds ratio [OR] 0.20; 95% confidence interval [CI] 0.05, 0.86, P = .03) and the nature of the recommendation (OR 4.73; CI 2.51, 8.92 for loop excision; OR 8.72; CI 2.57, 29.6 for conization; and OR 2.53; CI 1.30, 4.93 for repeat colposcopy, all against observation, P<.001). CONCLUSION: After colposcopy, women were more likely to comply with earlier, more intensive interventions, although the relative effect of follow-up interval and intervention could not be distinguished.

Adolescent↗
PubMed1998

Rehabilitation staff perceptions of characteristics of geriatric rehabilitation patients.

OBJECTIVE: To determine if professionals treating older rehabilitation patients regarded them as having different characteristics than younger rehabilitation patients, to derive factors from these perceptions, and to examine the impact of the discipline of the professional and other factors on these perceptions. DESIGN: Rehabilitation professionals at a random sample of facilities accredited by the Commission on Accreditation of Rehabilitation Facilities were surveyed to determine their level of agreement with 60 items addressing characteristics of older rehabilitation patients. The items were derived from focus groups with rehabilitation staff members. PARTICIPANTS: One thousand sixty-three rehabilitation professionals from nine disciplines (nursing, occupational therapy, physiatry, physical therapy, psychology, social work, speech pathology, therapeutic recreation, and vocational counseling) responded to the questionnaire and were included in the study. RESULTS: There was a wide range of agreement levels across the 60 items (range of median agreement, 12.7% to 93.5%). Factor analysis resulted in six categories of perceptions regarding older rehabilitation patients: (1) physical limitations, (2) motivational deficits, (3) psychological distress/need for support, (4) maturity and positive coping skills, (5) need for privacy/decreased adaptability, and (6) discharge complications. Significant differences across disciplines were found for five of six factors. Nurses agreed more strongly with the negative psychological factors (2, 3, and 5) compared to physical therapists, psychologists, and social workers. Physicians scored significantly higher than two other disciplines on the physical limitations factor. These differences may be related to the distinct role each discipline plays in the rehabilitation process. Older professionals also scored higher on four factors, likely because of personal rather than professional experience with aging. CONCLUSIONS: Treating professionals recognize differences between younger and older rehabilitation patients. Many of these perceived differences can be viewed as variables that require more effort and skill on the part of the treating professional. The training of rehabilitation professionals needs to better prepare individuals from all disciplines to adapt to age-specific differences.

Activities of Daily Living↗
PubMed1997

Comparison of 49 laparoscopic myomectomies with 49 open myomectomies.

STUDY OBJECTIVES: To compare the results of open myomectomy with those of laparoscopic myomectomy, and to assess complications, surgical results, total hospital cost, and morbidity associated with each procedure. DESIGN: Retrospective chart review. SETTING: Private practice of one surgeon, and Department of Obstetrics and Gynecology, Rush Medical College, Chicago, Illinois. PATIENTS: Ninety-eight women with symptomatic uterine leiomyomata. INTERVENTIONS: Forty-nine consecutive laparoscopic myomectomies were performed between 1993 and 1995, and 49 open myomectomies were performed between 1983 and 1995. MEASUREMENTS AND MAIN RESULTS: Indications for both procedures were similar, including menometrorrhagia, pelvic pain, and enlarging myomata. Mean operating time for open myomectomies was 133 minutes versus 264 minutes for laparoscopies (p <0.0001). Mean blood loss was 340 ml and 110 ml, respectively (p <0. 001). The greatest blood loss was 1000 ml in the open group and 800 ml in the laparoscopic group. Uterine size at surgery was 12 to 14 weeks in 42.9% of the open group and 9 to 11 weeks in 51% of the laparoscopy group. The open group incurred a total of 272 hospital days versus 29 days in the laparoscopic group (maximum 25 and 3 days, respectively; mean 5.6 and 0.6 days, respectively; p <0.001). The frequency of postoperative complications was higher in the open group (17) than in the laparoscopic group (5, p = 0.0068). Of patients in whom postoperative adhesions were evaluated, the overall frequency of adhesions was lower in the laparoscopic group. Three women in the open group required postoperative transfusions, compared with none in the laparoscopic group. Seven pregnancies have thus far occurred in the laparoscopic group. Three women delivered at term by elective cesarean section, at which no evidence of uterine dehiscence was found. Estimated average cost of each procedure, expressed in April 1995 dollars using the Consumer Price Index, were $14,461 for open myomectomies and $13,814 for laparoscopies (p = 0.65). Linear regression with residual analysis was performed on costs for both groups and revealed significantly increasing time trend for open myomectomies. During the years of this study, the open procedures increased in price at a rate of $868/year. The cost of laparoscopic myomectomies showed no time trend. CONCLUSIONS: Compared with open myomectomy, laparoscopic myomectomy had lower morbidity, no identifiable trend of increasing hospital cost, minimal hospital stay, and fewer complications.

Adult↗
PubMed1997

The Big Ten Student Suicide Study: a 10-year study of suicides on midwestern university campuses.

The Big Ten Student Suicide Study was undertaken from 1980-1990 to determine the suicide rates on Big Ten University campuses. The study design attempted to address many of the statistical and epidemiological flaws identified in previous studies of campus student suicides. The 10-year study collected demographic and correlational data on 261 suicides of registered students at 12 midwestern campuses. The largest number of suicides for both males and females were in the 20-24-year-old age group (46%), and amongst graduate students (32%). The overall student suicide rate of 7.5/100,000 is one half of the computed national suicide rate (15.0/100,000) for a matched sample by age, gender, and race. Despite the overall lower suicide rate, the analyses revealed that students 25 and over have a significantly higher risk than younger students. Although women have rates roughly half those of men throughout their undergraduate years, graduate women have rates not significantly different from their male counterparts (graduate women 9.1/100,000 and graduate men 11.6/100,000).

Adolescent↗
PubMed1993

Racial differences in the incidence of cardiac arrest and subsequent survival. The CPR Chicago Project.

BACKGROUND: Differences between blacks and whites have been reported in the incidence of several forms of cardiovascular disease, including hypertension and stroke. We examined racial differences in the incidence of cardiac arrest in a large urban population and in subsequent survival. METHODS: We collected data on all nontraumatic, out-of-hospital cardiac arrests in Chicago from January 1, 1987, through December 31, 1988, and compared the incidence and survival rates for blacks and whites. We examined the association between survival and race and seven other known risk factors by logistic-regression analysis. We computed incidence rates by coupling our data with U.S. Census population data. RESULTS: Our study population comprised 6451 patients: 3207 whites, 2910 blacks, and 334 persons of other races. The incidence of cardiac arrest was significantly higher for blacks than for whites in every age group. The survival rate after cardiac arrest was 2.6 percent in whites, as compared with 0.8 percent in blacks (P < 0.001). Blacks were significantly less likely to have a witnessed cardiac arrest, bystander-initiated cardiopulmonary resuscitation, or a "favorable" initial rhythm or to be admitted to the hospital. When they were admitted, blacks were half as likely to survive. The association between race and survival persisted even when other recognized risk factors were taken into account. We did not find important differences between blacks and whites in the response times of the emergency medical services. CONCLUSIONS: The black community in our study was at higher risk for cardiac arrest and subsequent death than the white community, even after we controlled for other variables.

Adolescent↗
PubMed1986

Temporal neocortical injuries in rats impair attending but not complex visual processing.

The effects of variations of the distance between the relevant stimuli and the animals' response sites were observed upon the performances of a black-white discrimination habit for normal rats or subjects prepared with either bilateral injuries to the visual or temporal neocortex. In addition, the animals were given a strict test of visual form perception. Subjects with injuries to the visual cortex failed the test of visual form perception but performed like normals in discriminating a spatially discontiguous problem. In contrast, subjects with temporal injuries exhibited enormous performance deficits when trained on a spatially discontiguous problem but performed like normals on the test of form perception. The findings parallel the results of studies using primates and suggest that bitemporal injuries result in impairments of attending and not of complex visual processing.

Animals↗
PubMed1977

An inexpensive microphotometer system for measuring silver grain densities in autoradiographs.

An inexpensive microphotometric system is described which will facilitate reading grain-dense areas in autoradiographic material. It is reliable, easy to operate and adaptable to most light microscopes with a dark field condenser. In addition to the microscope, the components include a photodiode, an operational amplifier and a digital mV meter. Data are presented to demonstrate the sensitivity of the system and to illustrate the differential variability between the microphotometer and the counting of grains by eye.

Animals↗
PubMed1976

Effects of successive unilateral ablations of principalis cortex upon performances of delayed alternation and delayed response by monkeys.

Monkeys were trained on delayed alternation (DA), and were then subjected to serial unilateral or simultaneous bilateral ablations of the banks of the sulcus principalis of each frontal lobe. When subjects with unilateral lesions were retrained on DA, their performances were intermediate to those of normal and bilateral animals. This interoperative training failed to protect the serially operated monkeys from losses of DA following their second-stage ablations, for they then performed as poorly as one-stage subjects and subjects prepared with serial ablations that were not given practice on the task between the two operations. Additional postoperative tests of delayed responding (DR) showed that both serially and simultaneously ablated subjects also had severe impairments of performance of DR. This result confirmed, in principle, a finding that monkeys with large unilateral ablations, if reoperated after many months for the removal of the contralateral dorsolateral perfrontal cortex, will thereafter exhibit DR deficits that are both severe and endure for a period of years. It contrasted sharply with a recent observation that DR is retained by monkeys subjected to two-stage symmetrical ablations of the principalis cortex, which suggests that recoveries of frontal-lobe functions are powerfully affected by the orders in which serial extirpations are performed.

Animals↗