View clinical trials related to Healthy.
Filter by:The goal of this research study is to identify biologic and lifestyle factors that may increase a person's risk of developing certain types of cancer.
Syncope is a syndrome consisting of a relatively short period of temporary and self-limited loss of consciousness caused by transient diminution of blood flow to the brain (most often the result of systemic hypotension). The objective of this study was to evaluate the effect of salt supplementation in vasovagal syncope prophylaxis.
The purpose of this study is to attempt to determine why estrogen levels are increased in African-American women as compared to Caucasian women by evaluating estrogen feedback on the brain. African-American women have increased bone mineral density, higher rates of twins, greater incidence of fibroids, and increased incidence of breast cancer below 40 years of age as compared to Caucasian women. These traits or illnesses are all believed to be estrogen-dependent. In fact, previous research has demonstrated increased estrogen levels in African-American women as compared to Caucasian women. However, the reason for these differences in estrogen levels has not been studied in humans. One possibility is that estrogen feedback on the brain differs between African-American and Caucasian women. Two small glands in the brain (hypothalamus and pituitary) respond to estrogen. The hypothalamus secretes GnRH (Gonadotropin-Releasing Hormone) that signals the pituitary to secrete the reproductive hormones, LH (Luteinizing Hormone) and FSH (Follicle Stimulating Hormone). These hormones act on the ovaries and signal the ovaries to produce estrogen and progesterone. Estrogen in the bloodstream then acts on the brain to stop this system when the blood has enough estrogen levels. This is called estrogen feedback. This study will determine whether there are differences in estrogen feedback between African-American and Caucasian women.
The purpose of this study is to study the effects of aging and estrogen on the brain. Specifically, this study will examine how the hypothalamus signals the pituitary gland to secrete reproductive hormones and how that changes with aging.
According to the National Institute of Mental Health, depressive disorders afflict over six million U.S. men annually. Most cases of moderate or severe depression are treated with antidepressants, including monoamine oxidase inhibitors, tricyclic antidepressants, and, more recently, selective serotonin reuptake inhibitors (SSRIs) and antidepressants with modest serotonin and norepinephrine reuptake inhibition but unknown mechanism-of-action. Over the past two years, prescribing data show a steady increase in antidepressant dispensing rates (especially including serotonin reuptake inhibitors) for adults. SSRIs are known to have an effect on ejaculatory function and are therapeutically used for treatment of premature (rapid) ejaculation. However, few studies have evaluated the potential impact of antidepressant medications on male fertility, and no studies have been published with respect to the impact of newer antidepressants, such as SSRIs, on male fertility. In the high-volume male infertility practice at New York Hospital-Cornell Medical Center, several patients have presented who have had a clear temporal association between SSRI use and impairment in sperm motility and/or sperm transport (emission). These men have shown improvement in sperm counts and motility after discontinuation of antidepressant medications. We propose a crossover pilot study of normal healthy males to ascertain possible effects of SSRIs on semen parameters. After initial screening semen analyses, subjects will take the SSRI paroxetine for five weeks. Serial semen analyses will be obtained while on medication and one month after discontinuation of medication. Comparisons between semen parameters on and off medication will be used to evaluate the frequency and significance of semen analysis changes during SSRI treatment.
The purpose of the study is to understand how the ovarian follicle (the fluid filled structure in the ovary that contains the egg) makes estrogen and other hormones during normal aging, in women with different ethnic backgrounds, and in Fragile X premutation carriers. During reproductive aging, estradiol levels are increased, a phenomenon that may be related to increased aromatase activity. The investigators' own preliminary data suggest that estradiol is increased in African-American women compared to Caucasian women, which may also be related to aromatase activity. In addition, the investigators have examined female fragile X premutation carriers who still have regular menstrual cycles and have demonstrated evidence of early ovarian aging compared to age-matched controls. **WE ARE RECRUITING ONLY WOMEN WITH FRAGILE-X PREMUTATION**
Patients will use the Conception Kit in their home and fill out a 22 question questionnaire in order to demonstrate their knowledge of the method of usage as described in the instructions and on the website: www.conceptionkit.com.
The conceptual framework underlying the TEACH Research Program is based on a specific theoretical approach designed to influence adolescent career choice, in this case towards a career in clinical research. The factors responsible for influencing career choice that form the foundation for our investigation are: 1) the importance of role models in career choice; 2) acquisition of knowledge in order to align ambitions; and 3) the participation of students in activities that actively challenge and engage them. These three factors are addressed by the following three components of the TEACH Research Intervention: 1) participation in a research team consisting of a multi-tiered structure of mentors; 2) classroom instruction of clinical research knowledge and career strategies; and 3) a hands-on clinical research experience through an internship on the Hospitalist Project. The evaluation of TEACH Research (Teaching Early Achievers for Careers in Health) aims to rigorously evaluate a precollege enrichment program in clinical research targeting high school students particularly underrepresented minorities, in order to increase the entry and success of these students into careers in clinical research. Through these measures, the TEACH Research Program will educate high achieving minority students and in turn hopefully encourage and promote these students to think about a career in clinical research.
The purpose of this study is to determine whether asthmatics have different adenosine receptor expression profiles than healthy controls. We hypothesize that asthmatics will have increased adenosine receptor expression versus control subjects. We also want to study the effects of allergen inhalation on adenosine receptor expression in asthmatics. We believe that adenosine receptor expression will be upregulated after allergen inhalation. Both hypotheses are being tested in sputum and peripheral blood.
The proposed research is an observational study designed to compare estrogen and progesterone serum levels with knee and ankle joint laxity, and muscle reaction time as a measure of neuromuscular function. Three groups of women athletes with differing estrogen and progesterone profiles (normal menstrual cycles, amenorrheic, and exogenous estrogen supplementation) and one control group (male collegiate athletes) will be used to compare differences in joint laxity and neuromuscular function. Blood levels of estrogen and progesterone will be measured at four time points across the menstrual cycle. Joint laxity and muscle reaction time will also be measured at each of these points. The investigator hypothesizes that knee and ankle joint laxity and muscle reaction time will significantly increase with increasing estrogen and progesterone levels.