Search PubMed⌕ Search

Biomedical subjects

A Kinney

Publications and source records attributed to A Kinney.

17 recordsLinked to original sources
PubMed2005

Predictors of antral follicle count during the reproductive years.

BACKGROUND: We sought to identify indicators of antral follicle count which would be serviceable to clinicians seeking to estimate the number of ovarian follicles without relying on sonographic counts. METHODS: We examined the relations of chronological age and four potential indicators of ovarian age-ovarian volume, FSH, dimeric inhibin B and estradiol-to antral follicle count in 176 recently pregnant women. We identified the regression models which best predict low antral follicle count (< or =10 follicles). RESULTS: Chronological age, ovarian volume, FSH and inhibin B were each significantly associated with antral follicle count. Fifty-three (30.1%) women had < or =10 antral follicles. In the total sample, at the cutpoint corresponding to 80% sensitivity, the positive predictive value for a regression model with all four variables was 60%. All regression models performed less well in women <35 years (13.9% with low count) than in women > or =35 years (52.0% with low count). In older women, the positive predictive value for the model with all four variables was 79%, compared with 60% for a model with chronological age alone. CONCLUSIONS: Our models provide a basis for advising women aged > or =35 years who are either trying to conceive or wish to learn whether they may postpone childbearing.

Adult↗
PubMed2004

Trisomic pregnancy and the oocyte pool.

BACKGROUND: We tested the hypothesis that trisomy risk is increased for women with fewer oocytes (older ovarian age) than other women of the same chronological age. METHODS: Our study compared three indicators of ovarian age-number of antral follicles, level of dimeric inhibin B, level of FSH-among women who had trisomic pregnancy losses (n = 54) with those among women who had other losses (24 with other chromosomally abnormal loses, 21 with chromosomally normal losses) or who had chromosomally normal births (n = 65). RESULTS: Ovarian age indicators did not differ between women with trisomic spontaneous abortions and the three comparison groups. Compared with live birth controls, adjusting for chronological age, we estimate that, on average, among trisomy cases the geometric means of 1 + follicle count, inhibin B and FSH are about 7.5% higher, 16.6% higher and 5.5% lower, respectively, with all 95% confidence intervals including zero. The sample size was sufficient to detect moderate differences (0.52 standard errors of regression) between trisomy cases and live birth controls. CONCLUSIONS: Although our data do not support our hypothesis, they leave open the possibility that changes in follicular development unrelated to the size of the oocyte pool influence abnormal chromosome segregation.

Abortion, Spontaneous↗
PubMed2000

Trisomic pregnancy and earlier age at menopause.

We tested the hypothesis that the connection between advanced maternal age and autosomal trisomy reflects the diminution of the oocyte pool with age. Because menopause occurs when the number of oocytes falls below some threshold, our hypothesis is that menopause occurs at an earlier age among women with trisomic pregnancies than it does among women with chromosomally normal pregnancies. To determine their menstrual status, we interviewed women from our previous study of karyotyped spontaneous abortions who, in 1993, were age >/=44 years. Premenopausal women completed interviews every 4-5 mo, until menopause or until the study ended in 1997. The primary analyses compare 111 women whose index pregnancy was a trisomic spontaneous abortion with two groups: women whose index pregnancy was a chromosomally normal loss (n=157) and women whose index pregnancy was a chromosomally normal birth (n=226). We used a parametric logistic survival analysis to compare median ages at menopause. The estimated median age at menopause was 0.96 years earlier (95% confidence interval -0.18 to 2.10) among women with trisomic losses than it was among women with chromosomally normal losses and chromosomally normal births combined. Results were unaltered by adjustment for education, ethnicity, and cigarette smoking. Our results support the hypothesis that trisomy risk is increased with decreased numbers of oocytes. Decreased numbers may indicate accelerated oocyte atresia or fewer oocytes formed during fetal development.

Abortion, Spontaneous↗
PubMed2000

Alzheimer's disease in the parents of women with trisomic spontaneous abortions.

We tested whether familial aggregation of Down syndrome and Alzheimer's disease (AD) is present for trisomies of other autosomes. We compared rates of Alzheimer-like dementia in the parents of women with trisomic pregnancy losses (n = 109) with those in parents of women with chromosomally normal losses (n = 151) and births (n = 216). Relative risks of Alzheimer-like dementia in parents of women with trisomic losses were 1.2 (95% CI 0.6, 2.2) and 0.9 (95% CI 0.5, 1.5) in comparison to parents of women with chromosomally normal losses and births, respectively. Associations were similar among women whose index pregnancy occurred before age 35 or later. Our data do not support an association between the occurrence of AD and trisomy of all autosomal chromosomes. They raise the possibility that familial aggregation with AD is specific to trisomy 21.

Abortion, Spontaneous↗
PubMed1997

Human exposure to PCBS: modeling and assessment of environmental concentrations on the Akwesasne reservation.

The Mohawk Nation at Akwesasne, comprised of approximately 10,000 people, is located along the St. Lawrence River in upstate New York. The Akwesasne reservation has been contaminated by local industries, which are located on the St. Lawrence River and its tributaries, and by upstream sources on the Great Lakes. The closest known source of contamination to the reservation is General Motors (GM) Foundry, which is located less than 100 feet from the reservation's border. This facility is listed on the Environmental Protection Agency's National Priority List and the New York State's Department of Environmental Conservation's (NYSDEC) inactive hazardous waste disposal site list. Contamination to the reservation arising from discharge and secondary transport mechanisms has caused concern to the Mohawk people of Akwesasne. The characterization of the environment at Akwesasne required a historical review of existing environmental data, generation of a database, review of existing data, sampling to augment existing data, data analysis, data modeling and data generation based on a chosen model for all environmental pathways of interest. The objectives this work were to: 1) assess the quality of existing data, 2) create a database which will manage the over 6000 samples recorded taken from the local area, 3) augment the existing data with additional sampling, 4) determine the degradation or attenuation of PCBs and specific congeners in various environmental media over time, and 5) create a model that estimates environmental concentrations of PCBs retro- and pro-spectively for times that sampling had not occurred. The results of this process yielded concentrations of PCBs, congener specific and total, in several environmental medium. Modeling of environmental concentrations through a thirteen-year time period was performed for a fish, wildlife and surface soil. Other media were not modeled due to limited information or non-detectable concentrations reported in past work. Additionally, the study participants activity, consumption and residential information was considered when limiting this modeling effort. The results of this work were used to estimate environmental concentrations through time and space. The results of this work were extremely valuable when determining areas of concern and provided the basis for a detailed exposure assessment of 97 women who reside at the Reservation.

Animals↗
PubMed1996

Chromosomal differences in susceptibility to meiotic aneuploidy.

A basic question concerning the origins of germ cell aneuploidy is whether the same mechanisms operate for all chromosomes, or whether there are chromosome-specific factors influencing the susceptibility to nondisjunction. Although selective loss of some trisomies in early gestation may contribute to the observed differences in trisomy frequency, data from spontaneous abortions, early embryos and gametes strongly suggest that there are real differences in the frequency with which different trisomies arise. In particular the preponderance of trisomy 16 and acrocentric trisomy appears to be present at conception. Maternal and paternal age relationships also differ among trisomies, as do the extent of maternal and paternal contributions, and the relative frequency of meiosis I and meiosis II errors. Recombination patterns associated with nondisjunction also show chromosomal differences. Chromosomal differences in length, centromere position, pericentromeric and other repetitive sequences, recombination patterns and chromatin characteristics might all be related to a differential susceptibility to aneuploidy, but no current explanation accounts for the excess of maternally derived trisomy 16. The existence of chromosome-specific factors makes extrapolation from observations on one chromosome to all aneuploidy unwise, both for investigations into the causes of aneuploidy, and for surveillance of aneuploidy frequency.

Abortion, Spontaneous↗
PubMed1995

Cigarette smoking and spontaneous abortion of known karyotype. Precise data but uncertain inferences.

Data from the first phase (1974-1979) of this New York City case-control study showed that 1) cigarette smoking during pregnancy was associated positively with chromosomally normal spontaneous abortion and 2) both past and current smoking were associated inversely with trisomic loss in women under age 30 years and positively in older women. The authors used data from two subsequent study phases (1979-1982 and 1982-1986) to test the stability of these associations over time and the homogeneity between payment groups (private vs. public). Spontaneous abortions (cases) were classified as chromosomally normal (n = 1,388), trisomic (n = 557), or other chromosomally aberrant (n = 409). Controls (n = 4,165) were women who had registered for prenatal care before 22 weeks' gestation and delivered at 28 weeks or later. For chromosomally normal loss, later data gave modest support to prior observations. In the total sample, current smoking (defined as smoking during the month of the last menstrual period) of 14 or more cigarettes per day was increased among chromosomally normal cases in comparison with controls (adjusted odds ratio (OR) = 1.3, 95% confidence interval (CI) 1.1-1.7) and in comparison with other aberrant cases (adjusted OR = 1.2, 95% CI 0.8-1.8). Stronger associations in public patients than in private patients (adjusted odds ratios of 1.4-1.5 versus 0.8-0.9, respectively) might indicate either a mediating effect of social disadvantage or a chance fluctuation. For trisomic loss, later data did not support prior observations. Associations between trisomy and past or current smoking did not vary significantly with age in either payment group; assuming no effect modification of age, adjusted odds ratios for smoking in relation to trisomy were 0.9-1.0.

Abortion, Spontaneous↗
PubMed1991

Caffeine and spontaneous abortion of known karyotype.

We tested associations of caffeine from beverages with spontaneous abortions of known karyotype. Spontaneous abortions (cases) were classified as chromosomally normal (n = 510) or chromosomally aberrant (n = 389) and, within the latter category, by type of aberration (237 trisomies, 54 monosomies X, 49 triploidies, 49 others). Controls registered for prenatal care before 22 weeks gestation and delivered at 28 weeks or later (n = 1,423). Caffeine intake in the perifertilization period did not differ among case groups and controls. For the highest category, 225+ mg/day, odds ratios (OR), adjusted for payment group and maternal age, were 1.0 for chromosomally normal cases, 0.9 for trisomies, 1.6 for monosomies X, and 0.8 for triploidies. Caffeine intake during pregnancy was tested for associations with chromosomally normal loss using the chromosomally aberrant cases to provide a robust comparison group. Although the proportion of subjects with intake of 225+ mg/day of caffeine intake in the perifertilization period does not influence the risk of chromosomally normal loss or trisomy. For monosomy X and triploidy, no strong associations were observed, but numbers were insufficient to rule out moderate effects. For caffeine intake during pregnancy, we found little evidence to support an influence on chromosomally normal loss.

Abortion, Spontaneous↗
PubMed1990

Disturbed children's and adolescents' comprehension of psychological mechanisms of defense.

This study examined the role of Piagetian logical and analytical reasoning in the comprehension of psychological defense mechanisms among 26 emotionally disturbed boys. Participants assigned to one of three Piagetian cognitive stages, listened to vignettes depicting defensive behaviors of various degrees of logical and structural complexity. Results indicated that, although both within- and between-group performances were at variance with theoretical expectations, consistent age trends in the comprehension of defense mechanisms were observed.

Adolescent↗
PubMedDate not supplied

The motor core of speech: a comparison of serial organization patterns in infants and languages.

Comparison of serial organization of infant babbling and early speech with that of 10 languages reveals four movement-related design features reflecting a deep evolutionary heritage: (1) the cyclical consonant-vowel alternation underlying the syllable, a "Frame" for speech consisting of mandibular oscillation, possibly evolving from ingestive cyclicities (e.g., chewing) via visuofacial communicative cyclicities (e.g., lipsmacks); (2) three intracyclical consonant-vowel co-occurrence preferences reflecting basic biomechanical constraints-coronal consonants-front vowels, dorsal consonants-back vowels, and labial consonants-central vowels; (3) a developmental progression from above-chance to below-chance levels of intercyclical consonant repetition; (4) an ease-related labial consonant-vowel-coronal consonant sequence preference for word initiation. These design features presumably result from self-organizational responses to selection pressures, primarily determined by motor factors. No explanation for these design features is available from Universal Grammar, and, except for feature 3, perceptual-motor learning seems to have only a limited causal role in acquisition of any design feature.

Child↗