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M Lane

Publications and source records attributed to M Lane.

At least 73 records · Page 4Linked to original sources
PubMed1997

The distribution of estrogen receptor-beta mRNA in forebrain regions of the estrogen receptor-alpha knockout mouse.

Neurons in the hypothalamus of estrogen receptor alpha-knockout (ER alphaKO) mice have been shown to concentrate radiolabeled estrogen and estrogen treatment regulates the expression of progesterone receptor mRNA. The purpose of the present study was to utilize in situ hybridization histochemistry to determine the anatomical distribution of ER beta mRNA in ER alphaKO mouse forebrain. The results of these studies revealed an extensive distribution of ER beta mRNA in the hypothalamic regions including medial preoptic area, suprachiasmatic nucleus, paraventricular nucleus, dorsomedial nucleus, medial tuberal nucleus, and the premammillary nuclei. Additional labeled perikarya were also detected in the glomerular layer of the olfactory bulb; tenia tecta; anterior septum; bed nucleus of the stria terminalis; medial, basolateral and cortical nuclei of the amygdala; cerebral and entorhinal cortex; the septohippocampal nucleus; Ammon's horn of the hippocampus and the dorsal raphe. The results of these in situ hybridization histochemical studies have provided novel information about the distribution of ER beta mRNA in the ER alphaKO mouse forebrain. In addition, these morphological data provides evidence that estrogen may exert its actions in the ER alphaKO mouse brain via ER beta and thereby maintain organizational and activational effects.

Animals↗
PubMed1997

Differential regulation of mouse embryo development and viability by amino acids.

The amino acid requirements of the preimplantation mouse embryo in culture changes as development proceeds from the zygote to the blastocyst stage. Eagle's non-essential amino acids and glutamine significantly increased cleavage rates during the first four cell cycles, while Eagle's essential amino acids without glutamine did not confer any benefit to embryo development before the eight-cell stage. After the eight-cell stage, non-essential amino acids and glutamine no longer stimulated cleavage rates but significantly increased blastocoel development and blastocyst hatching. In contrast, after the eight-cell stage essential amino acids increased cleavage rates as well as stimulating development of the inner cell mass of the resultant blastocysts. Fetal development after transfer of blastocysts was also significantly increased by culture with essential amino acids from the eight-cell stage. Consequently highest rates of development in vitro and viability after transfer were achieved when embryos were cultured with non-essential amino acids and glutamine to the eight-cell stage followed by development to the blastocyst stage in the presence of all 20 amino acids. Analysis of the parameters measured revealed a significant relationship between number of blastocyst cells and inner cell mass development with viability after transfer. Blastocyst formation and hatching could not be used to assess subsequent developmental potential.

Amino Acids↗
PubMed1996

Is body focus restricted to self-evaluation? Body focus in the evaluation of self and others.

OBJECTIVE: Clinicians have suggested that the core pathology of the eating disorders is an extreme body focus in self-evaluation. This study investigated whether women who focus on their own bodies place a similar focus on body shape when evaluating others and expect others to have a strong body focus in their self-evaluations. METHOD: Eighty-four undergraduate women completed the Eating Attitudes Test (EAT-26), which largely measures body focus in self-evaluation. Each was also shown a series of photographs of women and asked what aspects of the photos they first noticed and how the depicted women felt about themselves. Finally, each responded to scenarios in which they or a hypothetical woman overate or dieted. RESULTS: High EAT-26 scores were associated with an elevated number of "fat" or "thin" feelings attributed to women in the slides and a marginally greater number of body-related observations made about the slides. High EAT-26 scores were also associated with inferred negative feelings of others after overeating and positive feelings of others after dieting. In fact, the relationships between EAT-26 scores and feelings in response to hypothetical overeating and dieting situations were no stronger when applied to the self than when applied to others. However, when presented with a situation in which they overate, participants showed stronger relationships between their EAT-26 scores and their expected weight change and dieting behavior than they predicted would occur for others after an identical period of overeating. DISCUSSION: Extrapolating findings to a clinical population, women with eating disorders may focus on others' body shapes as well as their own. These women may also expect others to be as emotionally invested in their own body shapes as they are themselves, but may not expect others to be as prone to gain weight or to diet as strictly as they do. Treatment for this somewhat recalcitrant belief system is discussed, as are directions for future research.

Adolescent↗
PubMed1996

Environment of the preimplantation human embryo in vivo: metabolite analysis of oviduct and uterine fluids and metabolism of cumulus cells.

OBJECTIVE: To determine the levels of metabolites surrounding the human oocyte and embryo in vivo. DESIGN: Oviduct and uterine fluids were collected throughout the menstrual cycle. Cumulus cells were collected at oocyte retrieval and their production of metabolites was assessed. Samples were analyzed for pyruvate, lactate, and glucose by microfluorimetry. PATIENTS: Luminal fluids were collected from naturally cycling patients at the time of routine clinical investigation. Patient consent and hospital ethics approval were obtained for this study. RESULTS: Pyruvate in the oviduct did not vary with the day of cycle, the mean value was 0.24 mM. Lactate and glucose concentrations varied with the day of cycle; lactate increasing from 4.87 mM in the follicular phase to 10.50 mM at the time of ovulation, whereas glucose decreased from 3.11 mM in the follicular phase to 0.50 mM midcycle and subsequently increased to 2.32 mM in the luteal phase. The concentrations of pyruvate, lactate, and glucose in uterine fluid remained constant throughout the cycle (0.10, 5.87, and 3.15 mM, respectively). All metabolite concentrations in uterine fluid were significantly different from those in the oviduct midcycle. Cumulus cells readily consumed glucose in vitro, with lactate being the major metabolite produced. CONCLUSION: These data indicate that lactate and glucose concentrations in the oviduct change with day of cycle and that the human embryo is exposed to different metabolite concentrations as it passes along the tract. Furthermore, cumulus cells readily consume glucose, producing lactate. Therefore, the early human embryo is exposed to low glucose and high lactate levels in vivo.

Body Fluids↗
PubMed1996

Nutrient uptake and culture of Sminthopsis macroura (stripe-faced dunnart) embryos.

Glucose and pyruvate uptake by individual embryos were measured in a marsupial species (stripe-faced dunnart) and a eutherian species (mouse). At each stage of development, nutrient uptake by the dunnart embryo was around an order of magnitude greater than that of the mouse embryo. The pattern of glucose uptake by the dunnart embryo was not like that for any eutherian embryo, all of which have a low glucose uptake before the blastocyst stage. Rather, in the dunnart embryo there was a significant increase in glucose uptake after the third cleavage division, increasing from 13.6 pmol embryo h-1 at the 4-cell stage to 34.9 pmol embryo h-1 by the 8-cell stage. This increase in glucose uptake before blastocyst formation may be attributed to an increased energy demand associated with the movement of cells within the dunnart embryo. Using a new culture system, it was possible to culture 66% of dunnart embryos at the 2-4-cell stage and 80% of those at the 8-16-cell stage to the unilaminar blastocyst stage. Embryos cultured from the 2-cell to the 4-cell stage were retarded by around 12 h when they reached the blastocyst stage. Developmental retardation was also reflected in the pattern of nutrient uptake, which lagged behind that of embryos developed in vivo. The present study has shown that it is possible to culture the early marsupial embryo to the blastocyst stage in a serum-free culture system, while concomitantly quantifying embryonic nutrient requirements. Such an approach is essential for species where there is a paucity of material for study.

Animals↗
PubMed1996

Alleviation of the '2-cell block' and development to the blastocyst of CF1 mouse embryos: role of amino acids, EDTA and physical parameters.

The role of amino acids, ethylenediaminetetraacetic acid (EDTA), transferrin, oxygen, glucose, glutamine, taurine and ammonium in CF1 mouse zygote development in culture was examined. Non-essential amino acids and glutamine were shown to alleviate the 2-cell block in culture, and acted in synergy with EDTA to facilitate development to the blastocyst stage. In the presence of amino acids and EDTA, transferrin conferred no beneficial effect. Development of zygotes was significantly impaired if amino acids were removed from the collection medium, even when they were subsequently cultured in the presence of amino acids. Zygote development to the blastocyst stage was significantly improved when modular incubator chambers were used compared to using a conventional incubator, and when an oxygen concentration of 7% was used as opposed to 20%. Addition of taurine to medium containing non-essential amino acids had no effect on embryo development, whereas the removal of glutamine and/or glucose from the culture medium significantly reduced blastocyst cell number. Removal of glucose from the culture medium also resulted in a significant decrease in implantations. Ammonium, generated from the breakdown of amino acids, significantly reduced blastocyst development. EDTA was found to confer its beneficial effects during the first 48 h of culture, and indeed was inhibitory during the second 48 h, resulting in loss of subsequent viability. In summary, the data demonstrate that development of CF1 zygotes to the blastocyst stage is readily achievable. In the presence of non-essential amino acids and glutamine the removal of glucose is detrimental to CF1 mouse embryo development in culture and reduces subsequent viability. Optimal development and maintenance of viability requires more than one culture medium to support the preimplantation period.

Amino Acids↗
PubMed1996

Selection of viable mouse blastocysts prior to transfer using a metabolic criterion.

The success rate of human in-vitro fertilization (IVF) remains low, with only approximately 10% of embryos transferred resulting in a term pregnancy. A major contributor to this embryonic loss is poor embryo development in vitro. Such poor development can be attributed to both chromosomal and anatomic anomalies in oocytes after ovarian stimulation and to suboptimal embryo culture conditions. The low success rate of IVF is compounded by an inability to select those embryos most likely to implant after transfer (viable). Currently morphology is used almost exclusively as the sole criterion to decide which embryos are replaced. This procedure is not only subjective but has a poor correlation with subsequent developmental competence. Therefore, the development of techniques to quantify embryo viability prior to transfer will significantly increase pregnancy rates. We report here that the non-invasive assessment of glycolytic activity (percentage of glucose converted to lactate) in individual mouse blastocysts prior to transfer can be used successfully to identify viable embryos. Blastocysts with a low glycolytic activity, close to that of in-vivo developed blastocysts, had a significantly higher viability than those with abnormally elevated levels of glycolysis. Using glycolytic activity as a marker of viability resulted in a four fold increase in the pregnancy rate compared with embryos selected at random for transfer. We propose that the success of clinical IVF can be increased significantly by employing quantitative tests for viability.

Animals↗
PubMed1995

Removal of embryo-toxic ammonium from the culture medium by in situ enzymatic conversion to glutamate.

An enzymatic method for removing embryo-toxic ammonium from culture medium has been developed. Ammonium, produced by both embryo metabolism and spontaneous breakdown of amino acids at 37 degrees C, is transaminated by glutamate dehydrogenase to nontoxic glutamate. Initially, the individual components of the transamination reaction were titrated against mouse embryo development in vitro to determine embryo-safe levels. ADP, an allosteric activator of glutamate dehydrogenase, was found to inhibit embryo development and was therefore omitted from the final formulation (alpha-ketoglutarate, 0.44 mM; glutamate dehydrogenase, 0.375 U; NADH, 0.12 mM). It was found that 0.30 mM ammonium could be removed from the culture medium in situ in 3 h. In situ removal of ammonium significantly increases both blastocyst cell number, implantation, fetal development, and fetal weight after transfer. Removal of ammonium by the conventional method of renewing the culture medium also increased blastocyst cell number but did not affect postimplantation development. In conclusion, it is possible to alleviate the toxic effects of ammonium in vitro on pre- and postimplantation mouse embryo development by its transamination in situ, thereby facilitating the continual exposure to embryo-derived factor(s) which stimulates both pre- and postimplantation development.

Animals↗
PubMed1995

Breast cancer screening: racial/ethnic differences in behaviors and beliefs.

Racial/ethnic differences in breast cancer screening behaviors and beliefs were examined in 259 asymptomatic women, 50 years old or older, who participated in a no-cost worksite breast cancer screening program. Hispanics were more likely than African Americans to report having had mammography in the past year. Caucasians and Hispanics were more likely than African Americans to report having had a clinical breast examination in the past year. African Americans to report having had a clinical breast examination in the past year. African Americans and Hispanics were more likely to practice monthly breast self-examination than were Caucasians. African Americans were more likely to report cancer-related fears and worries as barriers to mammography, whereas Caucasians were more likely to report being too busy, inconvenience, and procrastination as barriers. African Americans also were more likely to evaluate their physicians and other health professionals positively than were Caucasians. These results suggest a need to make a special effort to address cancer-related fears as barriers to screening among African Americans, and time-related barriers to screening among Caucasians.

Black or African American↗
PubMed1995

The Gross Motor Performance Measure: validity and responsiveness of a measure of quality of movement.

BACKGROUND AND PURPOSE: This article presents the results of a study to validate a measure of gross motor performance for its capacity to detect changes in the quality of movement in children with cerebral palsy aged 0 to 12 years. SUBJECTS AND METHODS: On two occasions, 4 to 6 months apart, physical therapists from three children's treatment centers assessed 106 children with cerebral palsy, 18 children who had sustained an acute head injury, and 29 nondisabled children. Validity was demonstrated by comparing changes on the measure across diagnoses, severity, and age groups. RESULTS: Several a priori hypotheses were supported; however, relationships with parent and therapist ratings were not clearly demonstrated. CONCLUSION AND DISCUSSION: The measure was found to be differentially responsive to changes in "stable" and "responsive" groups.

Analysis of Variance↗
PubMed1995

Cerebral palsy.

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Cerebral Palsy↗
PubMed1994

Subtypes of psychosocial adjustment to breast cancer.

By means of cluster analytic techniques, four subtypes of psychosocial adjustment were identified in a sample of 122 breast cancer patients who completed the Psychosocial Adjustment to Illness Scale. Internal consistency and internal validity of the derived typology were suggested by the finding that two different hierarchical agglomerative clustering methods (average linkage between groups, Ward's) produced similar solutions. Three of the derived subtypes reported normal affect levels but different patterns of relative strengths and dysfunctions, while the fourth subtype appeared to be highly distressed and globally maladjusted. External validation was demonstrated by differentiating the subtypes on variables of negative affect, avoidance coping, and fighting spirit. The clinical and heuristic implications of these findings are discussed. The findings highlight the need for comprehensive assessment of psychosocial functioning of cancer patients. They demonstrate that even non-emotionally distressed patients can have very different profiles of adjustment and may benefit from correspondingly individually tailored psychosocial interventions.

Adaptation, Psychological↗
PubMed1994

Training users in the gross motor function measure: methodological and practical issues.

BACKGROUND AND PURPOSE: The Gross Motor Function Measure (GMFM) is a criterion-referenced observational measure for assessing change in gross motor function for children with cerebral palsy (CP). The purposes of this report are to present data on the effects of training pediatric developmental therapists to administer and score the GMFM and to discuss some practical and methodological issues associated with training. SUBJECTS AND METHODS: A weighted kappa estimate pretraining and posttraining workshop was used to determine participants' agreement of scoring a videotaped GMFM assessment against experts' scoring of the same videotaped assessment. Several children with CP, representing a spectrum of ages, severities, and levels of function, were shown on the videotape. RESULTS: There was a significant improvement in agreement from a mean kappa of .58 to .82 (t = 15.38, df = 75, P < .001) for the first group and from .81 to .92 (t = 10.91, df = 72, P < .001) for the second group following training. CONCLUSION AND DISCUSSION: Although there are a number of advantages to using videotapes to train test users and to assess scoring reliability, this method does not evaluate participants' ability to administer the measure. Further work is needed to determine whether reliability is maintained in a clinical situation in which it is necessary to both administer and score the GMFM.

Adolescent↗
PubMed1994

Enhanced rates of cleavage and development for sheep zygotes cultured to the blastocyst stage in vitro in the absence of serum and somatic cells: amino acids, vitamins, and culturing embryos in groups stimulate development.

The aim of this study was to develop a serum-free culture system that could support high levels of cleavage and blastocyst formation from sheep zygotes developed in vitro. To this end, we investigated the effects on sheep zygote development of amino acids, ammonium, vitamins, and culture of embryos in groups in Synthetic Oviduct Fluid (SOF) medium supplemented with BSA (32 mg/ml). The inclusion of amino acids in the culture medium had no effect on the percentage of embryos arrested at the 8-16-cell stage when embryos were cultured singly in the same drop of medium for 6 days (43% in SOF; 41% in SOF+amino acids). However, in medium containing all Eagle's amino acids, replacing the culture medium every 48 h to alleviate ammonium toxicity significantly decreased the number of arrested embryos (6%; p < 0.05) and significantly increased blastocyst cell number (52 cells in SOF; 105 cells in SOF+amino acids; p < 0.01) and the number of embryos developing to the blastocyst stage (29% in SOF; 67% in SOF+amino acids; p < 0.05). When the medium was renewed every 48 h, nonessential amino acids and glutamine also significantly decreased the number of arrested embryos (p < 0.05). Culturing embryos singly or in groups in SOF medium with all Eagle's amino acids that was renewed every 48 h resulted in significant increases in blastocyst hatching and mean cell number (47%, 31%, and 79%; 105, 136, and 173 cells for embryos cultured singly, in groups of 2, and in groups of 4, respectively). After culture in groups of 4, blastocyst cell numbers were equivalent to in vivo-developed controls (160 cells) and significantly greater than those developed in serum (103 cells; p < 0.01). Analysis of blastocyst metabolism, expressed on a per-cell basis, revealed that amino acids did not affect either glucose uptake or lactate production, whereas the addition of amino acids and vitamins resulted in a significant increase in both parameters (p < 0.01). A similar response was observed in serum-derived blastocysts. Ammonium production by sheep blastocysts after culture in the presence of amino acids was significantly greater than that produced by mouse blastocysts, indirect evidence that ruminant embryos utilize amino acids to a greater extent than do rodent embryos.(ABSTRACT TRUNCATED AT 400 WORDS)

Amino Acids↗