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L Rhodes

Publications and source records attributed to L Rhodes.

At least 19 recordsLinked to original sources

A potent, nonpeptidyl 1H-quinolone antagonist for the gonadotropin-releasing hormone receptor.

Extensive development of the structure-activity relationships of a screening lead determined three important pharmacophores for gonadotropin-releasing hormone (GnRH) receptor antagonist activity. Incorporation of the 3,4,5-trimethylphenyl group at the 3-position, 2-(2(S)-azetidinyl)ethoxy group at the 4-position, and N-4-pyrimidinylcarboxamide at the 6-position of the quinolone core resulted in the identification of 4-(2-(azetidin-2(S)-yl)ethoxy)-7-chloro-2-oxo-3-(3,4,5-trimethylphenyl)-1,2-dihydroquinoline-6-carboxylic acid pyrimidin-4-ylamide (1) as a potent antagonist of the GnRH receptor. A 10(4)-fold increase in in vitro binding affinity is observed for the GnRH receptor as compared to the initial screening lead. Compound 1 exhibits nanomolar binding activity and functional antagonism at the human receptor and is 7-fold less active at the rhesus receptor. Intravenous administration of compound 1 to rhesus monkeys results in a significant decrease of the serum levels of downstream hormones, luteinizing hormone (79% decrease in area under the curve) and testosterone (92% decrease in area under the curve), at a dose of 3 mg/kg. Quinolone 1 is a potent nonpeptidyl antagonist for the human GnRH receptor that is efficacious for the suppression of luteinizing hormone and testosterone in primates.

Animals↗

Altered serotonin 2A receptor activity in women who have recovered from bulimia nervosa.

OBJECTIVE: The authors' goal was to confirm that brain serotonin (5-HT) alterations are present in patients who have recovered from bulimia nervosa. Positron emission tomography imaging with [(18)F]altanserin was used to characterize binding of the 5-HT(2A) receptor, which might contribute to altered feeding, mood, or impulse control. METHOD: Nine women who had recovered from bulimia nervosa (they had no episodes of binge eating or purging, were at normal weight, and had regular menstrual cycles for more than 1 year) were compared with 12 female volunteers who had never had bulimia. RESULTS: The healthy volunteers, but not the women who had recovered from bulimia nervosa, had an age-related decline in 5-HT(2A) binding. Women who had recovered from bulimia nervosa had a reduction of medial orbital frontal cortex 5-HT(2A) binding. CONCLUSIONS: The lack of age-related changes in 5-HT activity is further evidence of 5-HT alterations in subjects who have recovered from bulimia nervosa. In addition, vulnerabilities for eating disorders, impulse dyscontrol, and mood disturbances may involve 5-HT and frontal lobe activity.

Adolescent↗

State- and sex-specific prevalence of selected characteristics--Behavioral Risk Factor Surveillance System, 1996 and 1997.

PROBLEM/CONDITION: High-risk behaviors (e.g., physical inactivity, cigarette smoking, and drinking and driving) and lack of preventive health care (e.g., screening for cancer) are associated with morbidity and mortality from chronic disease and injury. The Behavioral Risk Factor Surveillance System (BRFSS) collects state-specific information to determine the prevalence of such behaviors and preventive practices. By using the BRFSS, states can gain a better understanding of the factors that have a major affect on the health of their adult populations. The BRFSS is also used to monitor progress toward national health objectives. REPORTING PERIOD COVERED: 1996 and 1997. DESCRIPTION OF SYSTEM: The BRFSS is a state-based telephone survey of the civilian, noninstitutionalized, adult (i.e., persons aged 18 years) population. In both 1996 and 1997, 50 states, the District of Columbia, and the Commonwealth of Puerto Rico participated in the BRFSS. RESULTS: As in previous years, state- and sex-specific variations occurred in the prevalence of high-risk behaviors, awareness of certain medical conditions, use of preventive health services, and health-care coverage. For example, in 1997, the percentage of adults who reported being current cigarette smokers ranged from 13.8% to 30.7% among states (median: 23.2%), and the percentage of adults who reported driving after drinking too much alcohol ranged from 0.6% to 5.3% (median: 1.9%). Binge drinking varied substantially not only by state (range: 6.3%-23.3%; median: 14.5%) but also by sex (men: 22.3%; women: 6.7%). Similarly, the prevalence of overweight varied considerably by sex: 62.2% of men and 44.5% of women were overweight in 1997. INTERPRETATION: The 1996 and 1997 BRFSS data demonstrate that U.S. adults engage in behaviors that are detrimental to their health. The data also demonstrate that many adults are making efforts to prevent chronic disease and injury. The prevalence of certain behaviors and health practices differs between states and between men and women. The reasons for these differences by state and sex are subjects for further analysis, but only through continued surveillance can the areas that need further study be identified. PUBLIC HEALTH ACTIONS: Data from the BRFSS are useful in developing and guiding public health programs and policies. For many states, the BRFSS is the only source of state-level data on behaviors and practices related to chronic disease and injury; therefore, BRFSS data are vital for effective decision-making at the local level. States will continue to use these data to help prevent premature morbidity and mortality among their adult population and to assess progress toward national health objectives.

Adult↗

Estradiol causes a dose-dependent stimulation of prostate growth in castrated beagle dogs.

BACKGROUND: Previous studies have shown that chronic treatment of castrate dogs with androgen and estrogen results in significant prostate growth. Estrogen treatment of castrate dogs in the absence of androgen has resulted in conflicting data as reported by several authors. The purpose of this experiment was to evaluate the effect of a physiological dose of estradiol on prostate growth in dogs, using ultrasound to study size changes over time. METHODS: Dogs (n = 25) were randomly divided into groups (n = 5) and treated as follows: castration alone (CC), castration plus low dose estradiol (E(2) low), castration plus high estradiol (E(2) high), castration plus estradiol and androstanediol (E(2)A), or no treatment (normal controls, NC). Silastic implants containing 5alpha-androstan-3alpha-17beta-diol (3alphadiol), and/or 17beta-estradiol were used for continous delivery of steroids. Prostate volume was measured by transrectal ultrasonography, and blood was drawn for hormone and sex hormone binding globulin (SHBG) determinations. RESULTS: Results show that serum estradiol and SHBG levels were fairly constant over 12 weeks in all groups. Estradiol-treated groups had mean serum estradiol values of approximately 40 and 60 pg/ml, respectively. Initially, all groups had similar prostate volumes. Over 12 weeks the castrate dogs had a decline in prostate volume, whereas the intact dogs and those treated with E(2) and 3alpha-diol maintained a constant prostate volume. Estradiol treatment caused a large, late onset (week 7), dose-dependent increase in prostate volume relative to the intact group (P < 0.01). At 12 weeks, animals were euthanized and prostates weighed. The mean prostate weights in each group were: NC 14.8 +/- 2. 9, CC 2.4 +/- 0.5, E(2)A 9.7 +/- 2.0, E(2) low 21.7 +/- 4.3, and E(2) high 63.6 +/- 12.6 g (geometric mean +/- SEM). Histologically, prostates of estrogen-treated dogs showed metaplastic squamous epithelium. CONCLUSIONS: These results demonstrate that estradiol causes marked dose-dependent stimulation of prostate growth in the castrate dog.

Anabolic Agents↗

State-specific prevalence of selected health behaviors, by race and ethnicity--Behavioral Risk Factor Surveillance System, 1997.

PROBLEM/CONDITION: In the United States, disparities in risks for chronic disease (e.g., diabetes, cardiovascular disease, and cancer) and injury exist among racial and ethnic groups. This report summarizes findings from the 1997 Behavioral Risk Factor Surveillance System (BRFSS) of the distribution of access to health care, health-status indicators, health-risk behaviors, and use of clinical preventive services across five racial and ethnic groups (i.e., whites, blacks, Hispanics, American Indians or Alaska Natives, and Asians or Pacific Islanders) and by state. REPORTING PERIOD COVERED: 1997. DESCRIPTION OF SYSTEM: The BRFSS is a state-based telephone survey of the civilian, noninstitutionalized, adult (i.e., persons aged > or = 18 years) population. In 1997, all 50 states, the District of Columbia, and Puerto Rico participated in the BRFSS. RESULTS: Variations in risk for chronic disease and injury among racial and ethnic groups exist both within states and across states. For example, in Arizona, 11.0% of whites, 26.2% of Hispanics, and 50.5% of American Indians or Alaska Natives reported having no health insurance. Across states, the median percentage of adults who reported not having this insurance ranged from 10.8% for whites to 24.5% for American Indians or Alaska Natives. Other findings are as follows. Blacks, Hispanics, American Indians or Alaska Natives, and Asians or Pacific Islanders were more likely than whites to report poor access to health care (i.e., no health-care coverage and cost as a barrier to obtaining health care). Blacks, Hispanics, and American Indians or Alaska Natives were more likely than whites and Asians or Pacific Islanders to report fair or poor health status, obesity, diabetes, and no leisure-time physical activity. Blacks were substantially more likely than other racial or ethnic groups to report high blood pressure. Among all groups, American Indians or Alaska Natives were the most likely to report cigarette smoking. Except for Asians or Pacific Islanders, the median percentage of adults who reported not always wearing a safety belt while driving or riding in a car was > or = 30%. The Papanicolaou test was the most commonly reported screening measure: > or = 81% of white, black, and Hispanic women with an intact uterine cervix reported having had one in the past 3 years. Among white, black, and Hispanic women aged > or = 50 years, > or = 63% reported having had a mammogram in the past 2 years. Approximately two thirds of white, black, and Hispanic women aged > or = 50 years reported having had both a mammogram and a clinical breast examination in the past 2 years; this behavior was least common among Hispanics and most common among blacks. Screening for colorectal cancer was low among whites, blacks, and Hispanics aged > or = 50 years: in each racial or ethnic group, < or = 20% reported having used a home-kit blood stool test in the past year, and < or = 30% reported having had a sigmoidoscopy within the last 5 years. INTERPRETATION: Differences in median percentages between racial and ethnic groups, as well as between states within each racial and ethnic group, are likely mediated by various factors. According to published literature, socioeconomic factors (e.g., age distribution, educational attainment, employment status, and poverty), lifestyle behaviors (e.g., lack of physical activity, alcohol intake, and cigarette smoking), aspects of the social environment (e.g., educational and economic opportunities, neighborhood and work conditions, and state and local laws enacted to discourage high-risk behaviors), and factors affecting the health-care system (e.g., access to health care, and cost and availability of screening for diseases and health-risk factors) may be associated with these differences. ACTION TAKEN: States will continue to use the BRFSS to collect information about health-risk behaviors among various racial and ethnic groups. (ABSTRACT TRUNCATED)

Black or African American↗

Surveillance for use of preventive health-care services by older adults, 1995-1997.

PROBLEM/CONDITION: In 1995, a total of 55 million persons aged > or =55 years lived in the United States. The members of this large and growing segment of the population are major consumers of health care. Their access to medical and dental preventive services contributes to their likelihood of healthy later years and influences their long-term impact on the health-care delivery system. REPORTING PERIOD: 1995-1997. DESCRIPTION OF SYSTEMS: This report summarizes data from the National Health Interview Survey (NHIS), the state-based Behavioral Risk Factor Surveillance System (BRFSS), and the Medicare Current Beneficiary Study (MCBS) to describe national, regional, and state-specific patterns of access to and use of preventive services among persons aged > or =55 years. RESULTS: During 1995-1997, approximately 90% of persons aged > or =55 years living in the United States reported having a regular source of health-care services. However, only 75%-80% reported receiving a routine checkup during the preceding 2 years. The estimated percentage of persons who reported not being able to receive medical care because of cost was highest for those aged 55-64 years. Within this age group, the percentage was highest among Hispanics (4%) and persons without a high school diploma. Approximately 11% of Medicare beneficiaries reported delaying care be cause of cost or because they had no particular source of care. Percentage estimates varied according to age, race/ethnicity, and sociodemographic status. Approximately 95% of persons aged > or =55 years reported having their blood pressure checked during the preceding 2 years, but only 85%-88% had received a cholesterol evaluation during the preceding 5 years. The percentage of women receiving breast and cervical cancer screening decreased with increasing age, and the percentage of persons aged > or =55 years who had received some form of screening for colorectal cancer was low approximately 25% for fecal occult blood testing (FOBT) and 45% for endoscopy. State-specific rates of compliance with vaccination recommendations among persons aged > or =65 years were higher for influenza vaccine (range: 54%-74%) than for pneumococcal vaccine (range: 32%-59%), and compliance increased with advancing age. State-specific estimates of the percentage of annual dental visits varied 40%-75%, and 41%-88% of persons aged > or =65 years reported not having dental insurance. INTERPRETATION: Access to medical services among adults living in the United States is greater for persons aged > or =65 years, compared with those aged <65 years, presumably because of Medicare coverage. In contrast, use of dental services decreased, despite increased need for preventive and restorative dental care. Although Medicare covers many medical services for older adults, financial, personal, and physical barriers to both medical and dental care create racial, regional, and sociodemographic disparities in health status and use of health services in the United States. PUBLIC HEALTH ACTION: Continued surveillance of access to and use of health services among older adults (i.e., persons aged > or =65 years), as well as among persons aged 55-64 years, will help health-care providers target underserved groups, make Medicare coverage decisions, and develop public health programs to ensure equitable access to services and improve the health of older adults.

Aged↗

Spectrum of activity of lamotrigine in treatment-refractory bipolar disorder.

OBJECTIVE: New mood stabilizers are needed that possess efficacy for all phases of bipolar disorder. This study was designed to provide preliminary evidence for the safety and efficacy of a new anticonvulsant, lamotrigine, in adult patients with bipolar disorder who had been inadequately responsive to or intolerant of prior pharmacotherapy. METHOD: A 48-week, open-label, prospective trial was conducted in 75 patients with bipolar I or bipolar II disorder. Lamotrigine was used as adjunctive therapy (N = 60) or monotherapy (N = 15) in patients presenting in depressed, hypomanic, manic, or mixed states. RESULTS: Of the 40 depressed patients included in the efficacy analysis, 48% exhibited a marked response and 20% a moderate response as measured by reductions in 17-item Hamilton Depression Rating Scale scores. Of the 31 with a hypomanic, manic, or mixed state, 81% displayed a marked response and 3% a moderate response on the Mania Rating Scale. From baseline to endpoint, the depressed patients exhibited a 42% decrease in Hamilton depression scale scores, and the patients presenting with hypomania, mania, or a mixed state exhibited a 74% decrease in Mania Rating Scale scores. The most common drug-related adverse events were dizziness, tremor, somnolence, headache, nausea, and rash. Rash was the most common adverse event resulting in drug discontinuation (9% of patients); one patient developed a serious rash and required hospitalization. CONCLUSIONS: These open-label data provide preliminary evidence that lamotrigine may be an effective treatment option for patients with refractory bipolar disorder; however, potential benefits must be weighed against potential side effects, including rash.

Adult↗

Morphological and hormonal changes in the ventral and dorsolateral prostatic lobes of rats treated with finasteride, a 5-alpha reductase inhibitor.

BACKGROUND: In rats, the prostate is divided into three distinct lobes, and the lobes are dependent on androgens [testosterone (T) and dihydrotestosterone (DHT)] as trophic hormones. However, the reasons for the difference in the incidence of proliferative changes reported are not well-understood. Administration of finasteride, a 5-alpha reductase (5alphaR) inhibitor which selectively inhibits the conversion of T to DHT, results in elevated intraprostatic T levels. However, long-term (2 years) administration of finasteride results in no increase in proliferative changes in the ventral lobes of the rat prostate. Therefore, studies were designed to determine the differences in intraprostatic hormonal levels, morphology, and 5alphaR activity in different lobes of the rat prostate. METHODS: Sexually mature male Sprague-Dawley rats were used in all studies. Finasteride was administered orally to rats. The methodology included determination of intraprostatic T and DHT levels by radioimmunoassay, qualitative and quantitative evaluation of prostatic morphology, and in vitro determination of 5alphaR activities in rat prostatic lobes. RESULTS: A significant amount of 5alphaR activity was observed in the dorsal, ventral, and lateral lobes of the rat prostate. Both 5alphaR isozymes (types 1 and 2) were present in all lobes, based on 5alphaR activities observed at both acidic and neutral pH. Oral administration of finasteride (160 mg/kg/day) for 15 days resulted in significant (P < or = 0.001) decreases in intraprostatic DHT levels and increases in T levels; when compared to controls, the mean decrease in DHT levels in the ventral and the dorsolateral lobes was 86% and 94%, respectively, and the mean increase in T levels in the ventral and the dorsolateral lobes was approximately 3 times and 20 times, respectively, higher than in controls. Chronic administration of finasteride (80 mg/kg/day) for 6 months resulted in significant (P < or = 0.001) decreases in the weights of the prostatic lobes, which correlated with significant (P < or = 0.001) decreases in the total number of epithelial and stromal cells per gland in both the ventral and dorsolateral lobes of the prostate. There were no qualitative differences in prostatic morphology between the control and finasteride-treated groups. A short-term study in control rats exposed to bromodeoxyuridine (Brdu) showed that the number of Brdu-labeled cells in the dorsolateral lobe was significantly (P < or = 0.05) greater than in the ventral lobe. CONCLUSIONS: This first comparative study has highlighted some of the similarities and differences among the prostatic lobes of the rat. Inhibition of conversion of T to DHT with finasteride resulted in a significant increase in intraprostatic T levels and a significant decrease in DHT levels in rats; despite a significant increase in intraprostatic T levels, the prostate remained atrophic, indicating that DHT alone has a trophic effect on the prostate.

Animals↗

Peripheral radial incisions to treat inferior contact lens edge lift after penetrating keratoplasty for keratoconus.

A patient with marked corneal astigmatism and inferior contact edge lift after penetrating keratoplasty for keratoconus had corneal relaxing incisions (CRIs) on the donor button and radial incisions on the host cornea. Results were evaluated by computerized videokeratography and by refitting the contact lens. Two pairs of CRIs decreased astigmatism from 11.00 to 4.25 diopters but did not alleviate the contact lens edge lift, which was caused by excessive steepness in the keratoconic host cornea. After 6 radial incisions were made to flatten the inferior host cornea, the peripheral cornea flattened and the patient was successfully refitted with a contact lens.

Astigmatism↗

Sex hormone-binding globulin mediates prostate androgen receptor action via a novel signaling pathway.

Estradiol (E2) and 5alpha-androstan-3alpha,17beta-diol (3alpha-diol) have been implicated in prostate hyperplasia in man and dogs, but neither of these steroids bind to androgen receptors (ARs). Recently, we reported that E2 and 3alpha-diol stimulated generation of intracellular cAMP via binding to a complex of sex hormone-binding globulin (SHBG) and its receptor (R(SHBG)) on prostate cells. We speculated that this pathway, involving steroids normally found in the prostate, was involved in the indirect activation of ARs. Using the dog as a model to test this hypothesis in normal prostate, we investigated whether E2, 3alpha-diol, and SHBG stimulated the production of the androgen-responsive protein, arginine esterase (AE), the canine equivalent of human prostate-specific antigen. In cultured dog prostate tissue preincubated with SHBG, E2 and 3alpha-diol stimulated AE activity. These effects were blocked by hydroxyflutamide, an AR antagonist, and by 2-methoxyestradiol, a competitive inhibitor of E2 and 3alpha-diol binding to SHBG. In the absence of exogenous steroids and SHBG, AE also was significantly increased by treatment with forskolin or 8-Bromoadenosine-cAMP. These observations support the hypothesis that in normal prostate, E2 and 3alpha-diol can amplify or substitute for androgens, with regard to activation of the AR via the R(SHBG) by a signal transduction pathway involving cAMP. Because both E2 and 3alpha-diol are involved in the pathogenesis of benign prostatic hyperplasia in dogs and implicated in benign prostatic hyperplasia in man, antagonism of the prostatic SHBG pathway may offer a novel and attractive therapeutic target.

Animals↗

Pseudo-nitzschia in New Zealand and the role of DNA probes and immunoassays in refining marine biotoxin monitoring programmes.

Domoic acid (DA) was first detected in shellfish in New Zealand after the implementation of a comprehensive biotoxin monitoring programme for amnesic, paralytic, diarrhetic and neurotoxic shellfish toxins, following a suspected neurotoxic shellfish poisoning (NSP) event in early 1993. Both phytoplankton monitoring and shellfish flesh testing programmes have led to an extensive database which has helped link species of Pseudo-nitzschia to specific DA outbreaks. In 1994, P. pungens and P. turgidula were associated with DA contamination of shellfish, and cultured isolates of these species proved to be toxin producers. During 1996 the use of species-specific ribosomal RNA (rRNA)-targeted oligonucleotide probes and DA immunoassays led to the discovery of toxin production by P. fraudulenta, and showed the nontoxic P. heimii to be a major bloom former. Pseudo-nitzschia delicatissima, P. pseudodelicatissima and P. multiseries, also identified using rRNA-targeted probes, have been linked to DA contamination of New Zealand shellfish; P. australis is the main cause of DA in scallops. The relative amnesic shellfish poisoning (ASP) risk associated with different species, largely determined by DA immunoassays of cultured isolates, is now used by some regulators to refine risk assessments. Species identification is therefore vital so that shellfish growers, and health and industry officials, can make safe and economically sound harvesting decisions. The development and field trialling of DNA probes is proving invaluable in this context.

Animals↗

Effects of topical antiandrogen and 5-alpha-reductase inhibitors on sebaceous glands in male fuzzy rats.

The fuzzy rat, a genetic mutant between hairless and hairy albino rats, expresses androgen-dependent hypersecretion of sebum and hyperplastic sebaceous glands. Using this model for human acne, we examined the effects of inhibitors of human steroid 5 alpha-reductase isozymes, type I (MK 386) and type II (finasteride), and an androgen receptor blocker (RU58841) on regression of glandular and ductal hyperplasia. The above three agents, 1% weight volume, were dissolved into the vehicle (propylene glycol, alcohol and water) and applied on the backs of peripubertal male rats for 2 months. Control and castrate groups received vehicle alone. At 8 weeks, we examined the size the sebaceous glandular lobules and ducts in split epidermal preparations as well as in frozen sections of skin stained with osmium-potassium dichromate solution. The number of bromodeoxyuridine (BrdU)-positive cells was counted in the glandular lobes in split-skin tissues stained with BrdU immunochemistry. The results revealed that the sizes of both lobes and ducts in castrates were 40-60% smaller than in controls. RU58841 induced glandular and ductal regression equivalent to that in castrates. Finasteride induced a moderate degree of lobular and ductal reduction, whereas MK386 caused only ductal regression. Reduction of BrdU-positive cells in the sebaceous lobes was found in the skin treated with finasteride and RU58841. Serum concentrations of testosterone and dihydrotestosterone showed no significant changes in all drug-treated rats. The weight of the prostatic lobes was reduced significantly in rats treated with finasteride but not by the other two agents. RU58841 effectively counteracted endogenous androgens resulting in a suppression of growth of the sebaceous glands but not the prostate. This rodent model for androgen-dependent hyperplasia of the sebaceous glands is useful for the study of many pharmacological aspects comprising the rate of percutaneous absorption, stability and affinity to target organs of the testing compounds, and selection of adequate vehicle for topical application.

5-alpha Reductase Inhibitors↗

Effects of administration of testosterone, dihydrotestosterone, oestrogen and fadrozole, an aromatase inhibitor, on sex skin colour in intact male rhesus macaques.

For defining the mechanism of control of sex skin colour in male rhesus macaques (Macaca mulatta) by hormones, a spectrocolorimeter was used to monitor skin redness after administration of testosterone, dihydrotestosterone (a non-aromatizable androgen), oestradiol or fadrozole (an aromatase inhibitor that blocks the conversion of testosterone to oestrogen). Skin blood flow was measured by laser doppler. Eight 9-14 kg, 5-9 year old intact male rhesus macaques were given hormone, fadrozole or vehicle treatments in a cross-over experimental design. Baseline blood flow and colour measurements were taken in four paired tattoo defined areas on the back and legs of each animal (one pair in non-sex skin, three pairs in sex skin). Colour and blood flow measurements were taken 3-4 days after the first dose and, thereafter, once a week for 3-6 weeks. Measurements taken after treatments were compared with baseline and intra-animal comparisons were made between treatment and vehicle for each animal. In all animals after administration of 4 mg testosterone kg-1 (long-acting), redness in the sex skin areas increased (P = 0.032) by day 3 and returned to baseline values by day 7. Administration of 1 mg oestradiol kg-1 day-1 for 4 days caused increased redness in all animals (P = 0.007) similar in magnitude to that caused by testosterone. Administration of 0.1 mg dihydrotestosterone kg-1 day-1 for 4 days resulted in a nonsignificant decrease in redness (P = 0.09) on days 3-7. Treatment with fadrozole (0.25-0.5 mg kg-1 day-1) for 3 weeks caused sex skin to become significantly less red during treatment (P = 0.014). There was no significant change in redness in non-sex skin areas during any treatment. Sex skin blood flow increased in animals treated with testosterone, correlating with increased redness (R = 0.906), while blood flow in non-sex skin was unchanged. Increased redness after treatment with testosterone and oestrogen, no change in redness with treatment with dihydrotestosterone and a decrease in redness after treatment with fadrozole support the conclusion that oestrogen controls sex skin redness, and testosterone acts indirectly through conversion to oestrogen to cause increased sex skin redness in male rhesus macaques.

Animals↗

Behavioral risk factor surveillance of aged Medicare beneficiaries, 1995.

The Behavioral Risk Factor Surveillance System (BRFSS) is an ongoing State-based telephone survey of adults, administered through State health departments. The survey estimates health status and the prevalence of various risk factors among respondents, who include both fee-for-service and managed care Medicare beneficiaries. In this article the authors present an overview of the BRFSS and report 1995 regional results among respondents who were 65 years of age or over and who had health insurance. The advantages and disadvantages of using the BRFSS as a tool to monitor beneficiary health status and risk factors are also discussed.

Aged↗

Comparative sperm chromatin structure assay measurements on epiillumination and orthogonal axes flow cytometers.

The sperm chromatin structure assay (SCSA) measures the susceptibility of sperm nuclear DNA to acid-induced denaturation in situ, and was developed on two Ortho flow cytometers, an FC200 [Becton Dickinson Immunocytometry Systems (BDIS), Westwood, MA] and a Cytofluorograf 30 (BDIS), both having orthogonal axes of fluorochrome excitation, emission, and sample flow. Sperm cells are first treated with a pH 1.4 buffer to denature DNA in situ and then stained with the metachromatic dye acridine orange (AO). The metachromatic fluorescence measured reflects relative amounts of denatured (red fluorescence) and native (green fluorescence) DNA present per cell. The extent of DNA denaturation is quantified by the calculated parameter alpha t [alpha t = red/(red+green) fluorescence]. Alpha t variables important for correlations with fertility and toxicant-induced chromatin damage include mean (X alpha t), standard deviation (SD alpha t), and cells outside the main population (COMP alpha t). Mean green fluorescence intensity is an important measure for DNA content and/or degree of sperm chromatin condensation. This study showed that the SCSA can be successfully run on two epiillumination-type instruments, an Ortho ICP22A (BDIS, San Jose, CA) and Skatron Argus (Tranby, Norway), and two additional orthogonal axes instruments, a Becton Dickinson FACScan (BDIS) and a Coulter Elite (Coulter Corporation, Hialeah, FL). Epiillumination instruments produced a different fluorescence distribution than orthogonal instruments, but the resulting alpha t values showed strong conformity and interpretation of results was the same. SCSA values obtained on the Coulter Elite were most similar to the Cytofluorograf 30; the FACScan green fluorescence distribution was narrower and allowed resolution of cell doublets.(ABSTRACT TRUNCATED AT 250 WORDS)

Acridine Orange↗