Resistance training and bone mineral density in adolescent females.

OBJECTIVE: To examine the effects of 15 months of resistance training on bone mineral density (BMD) in female adolescents (aged 14 to 17 years). STUDY DESIGN: Participants were randomly assigned to either a training (n = 46) or control group (n = 21). BMD and body composition were measured by using dual-energy x-ray absorptiometry. Strength was assessed by means of one-repetition maximums for the leg press and bench press. The exercise group trained 30 to 45 minutes a day, 3 days per week, using 15 different resistance exercises. Control participants remained sedentary (<2 hours of exercise per week). RESULTS: Leg strength increased significantly (40%) in the exercise group, but there were no changes in the control group. Femoral neck BMD increased significantly in the training group (1.035 to 1.073 g/cm(2), P <.01) but not in the control group (1.034 to 1.048 g/cm(2)). No significant changes were seen in either group in lumbar spine BMD (1.113 to 1.142 g/cm(2) and 1.158 to 1.190 g/cm(2), respectively) or total body BMD (1.103 to 1.134 g/cm(2) and 1.111 to 1.129 g/cm(2), respectively). CONCLUSION: Resistance training is a potential method for increasing bone density in adolescents, although such a program would be best done as part of the school curriculum.

Effect of exercise on postprandial insulin responses in Mexican American and non-Hispanic women.

Postprandial insulin responses (integrated area under the curve) to an oral glucose load after a period of aerobic exercise and no exercise (control) were compared in sedentary normoglycemic Mexican American and non-Hispanic women pair-matched (n = 9) on total body fat mass (21.8 +/- 3.5 kg). The age (27.4 +/- 3.0 years), body mass index (BMI) (23.6 +/- 1.4 kg/m2), waist to hip ratio (WHR) (0.85 +/- .02), waist circumference (83.5 +/- 4.5 cm), lean mass (36.2 +/- 1.5 kg), and maximal O2 consumption ([VO2 max] 32.9 +/- 1.6 mL x kg(-1) x min(-1)) were similar, although the centrality index (subscapular/triceps skinfolds) was significantly greater in Mexican Americans (0.88 +/- 0.06 v 0.70 +/- 0.05, P < .01). Exercise (treadmill walking for 50 minutes at 70% VO2 max) and control trials were performed 4 weeks apart and 5 to 12 days after the onset of menstruation. A 75-g oral glucose load was administered 15 hours after the completion of each trial, with the subjects 12 hours postprandial. Blood samples were drawn prior to glucose ingestion (fasting, 0 minutes) and at minutes 15, 30, 60, 90, 120, and 150 postingestion. The postprandial insulin response was calculated using a trapezoidal method. In Mexican Americans, significant (P < .02) reductions in the postprandial insulin response (exercise v control, 6.5 +/- 1.0 v 8.5 +/- 1.4 pmol/L x min x 10(4)) and fasting insulin (exercise v control, 77.4 +/- 7.0 v 88.5 +/- 10.3 pmol/L) occurred after exercise compared with the control condition. In non-Hispanics, neither the postprandial insulin response (exercise v control, 7.2 +/- 1.0 v 6.2 +/- 0.9 pmol/L x min x 10(4)) nor fasting insulin (exercise v control, 77.0 +/- 8.2 v 82.9 +/- 8.9 pmol/L) were significantly different between trials. The postprandial insulin response in the control trial was significantly correlated with the change in the insulin response (control minus exercise) in the 18 women (r = .56, P = .01). No trial or group differences were found for postprandial glucose and C-peptide responses. Mexican American women have a high risk of developing type 2 diabetes, and aerobic exercise may be valuable in the prevention or delay of onset of diabetes by reducing peripheral insulin resistance.

Effects of 5-HT-releasing agents on the extracellullar hippocampal 5-HT of rats. Implications for the development of novel antidepressants with a short onset of action.

The effects of two selective 5-HT-releasing agents, 4-methylthioamphetamine (MTA) and 5-methoxy-6-methyl-2-aminoindan (MMAI), on the extracellular 5-HT concentration in the dorsal hippocampus was determined by microdialysis in anesthetized rats. After i.p. administration of 1 or 5 mg/kg of either compound, a rapid and significant increase of 5-HT basal release was observed. MTA (5 mg/kg) induced a maximal increase of about 2000% over the basal value 40 min after injection, which declined slowly, whereas MMAI (5 mg/kg) induced a maximal response of about 1350% which showed a rapid decline. Monoamine oxidase-A inhibitory properties of MTA, and MMAI's lack of similar properties might account for the difference between the two compounds. In agreement with previous information, a much lower increase in hippocampal 5-HT was observed in response to systemic fluoxetine. This difference in the magnitude of the response after MTA or MMAI and fluoxetine indicates that different mechanisms of action are operating. Based on evidence showing that an acute enhancement of 5-HT neurotransmission might result in the rapid appearance of therapeutic effects of serotonergic antidepressants, we suggest that MTA and MMAI might serve as leads for a novel family of compounds with a short onset of action useful for treating depression.

Neoplasia in snakes at the National Zoological Park, Washington, DC (1978-1997).

Of 291 juvenile and adult snakes examined post mortem over a 20-year period (1978-1997) at the National Zoological Park (NZP) in Washington, DC, 36 (24 females and 12 males) had neoplasms. Two snakes had tumours of two or three different types, but the other 34 snakes had only one type. All affected animals were adults and their average time on exhibit at the NZP was 108-9 months. Malignant neoplasms (79.5%) outnumbered benign neoplasms (20.5%). Of the malignant tumours, 19 (61.3%) were considered to have arisen in mesenchymal tissues, 11 (35.5%) were of epithelial origin, and one (3.2%) was derived from neuroectodermal tissues. All the benign neoplasms were of epithelial origin. Neoplasms of the lymphoid and haematopoietic tissues were the most common (12 cases), followed by tumours of the liver and biliary tract (seven cases) and the gastrointestinal tract (four cases).

Molecular modeling study of tubulosine and other related ipecac alkaloids.

A molecular modeling study of two alkaloids, tubulosine and psychotrine, isolated from the sap of Pogonopus speciosus, and other related ipecac alkaloids, showed that these flexible alkaloids favor a nonplanar structure. The biologically active compounds had conformations with a similar angle between aromatic ring A, the nitrogen in ring B, and ring D. This angle was related to the biological activity reported for these compounds. Our results support the hypothesis of two different types of receptor interactions, one for the nonplanar compounds and another for the planar compounds.

Knowledge, behavior, and fears concerning breast and cervical cancer among older low-income Mexican-American women.

INTRODUCTION: Although recent studies have documented the low participation level of Hispanic women in cancer screening, few have examined their predisposing knowledge and attitudes concerning cancer. We documented the knowledge and fears concerning cancer of an older population of Mexican-American women and how these factors relate to screening behavior and sociodemographic characteristics. METHODS: The data are from baseline surveys conducted before the start of a community cancer awareness and prevention program. Nine hundred twenty-three Mexican-American women were interviewed in-person about their knowledge, attitudes, and Pap smear and mammogram screening practices. RESULTS: Knowledge and attitude about cancer varied with age, education, type of health insurance, ability to speak English, and place of birth. Women 65 years of age and older were least knowledgeable of cancer-detection methods and screening guidelines. Those with only Medicare or Medicaid knew far less even compared to uninsured women. Women who did not speak English well were more likely not to know the cancer signs and symptoms, risk factors, and screening guidelines. Women who had knowledge of guidelines and detection methods were more likely to have had a recent screening. Older Mexican-American women with more fatalistic and fearful attitudes toward cancer were less likely to have had a recent Pap smear. CONCLUSIONS: The low screening participation among Mexican-American women may be due to their limited awareness and knowledge about breast and cervical cancer screening examinations. Our study highlights the need for wide-scale cancer screening interventions consistent with Mexican-American beliefs.

[Molecular modeling of N-isopropyl lisergamides analogous to LSD using molecular mechanics and quantum mechanical calculations]. / Modelado molecular de N-isopropil lisergamidas analogas al LSD, utilizando cálculos de mecánica molecular y mecánica cuántica.

Molecular mechanics and quantum mechanics were used to study the preferred conformations, electron densities and frontier orbitals of d-LSD and their analogs with the isopropyl amide group, compounds with reported activity over the serotonin receptor. Electron densities and frontier orbitals for isopropyl analogs were similar to d-LSD, so these properties can not be related with the changes in biological activity previously reported. It was found that isopropyl analogs have preferred conformations similar to d-LSD with small variation in the alkylamide group. The variation in the alkylamide group causes small variations in the orientation of the carbonyl amide group, our study suggests that this variation could affect the binding with the hydrophobic region of the receptor.

(+/-)-1-(2,5-Dimethoxy-4-ethylthiophenyl)-2-aminopropane (ALEPH-2), a novel putative anxiolytic agent lacking affinity for benzodiazepine sites and serotonin-1A receptors.

Serotonergic behavioral responses, effects on motor activity and core temperature, and binding properties of the novel putative anxiolytic amphetamine derivative (+/-)1-(2,5-dimethoxy-4-ethylthio-phenyl)-2-aminopropane (ALEPH-2), were examined in rodents in order to elucidate the mechanism underlying its anxiolytic-like effect. After peripheral administration in rats, ALEPH-2 induced some symptoms of the serotonergic syndrome, e.g. forepaw treading and flat body posture. Additionally, a decrease in motor activity was observed. No significant effects on the number of head shakes were observed after injection, although high inter-subject variability was noted. Higher doses of ALEPH-2, in the range exhibiting anxiolytic properties (4mg/kg), elicited significant hypothermia in mice. The affinity of the drug for 5-HT2A/2C receptors ([3H]ketanserin sites) was in the nanomolar range (Ki = 173 nM), whereas for 5-HT1A, benzodiazepine sites, and GABAA receptors, the affinity was micromolar of lower. Based on these results the mechanism of action and the anxiolytic-like properties of ALEPH-2 are discussed.

Prevalence of exercise-induced asthma in schoolchildren in Kingston, St. Andrew and St. Catherine, Jamaica.

A cross-sectional study was done, focusing on the prevalence of exercise-induced asthma in Jamaica and variables that may account for this rate. No previous study of this nature had been undertaken, and the investigators contend that there is a need to identify children who suffer from this condition but are unaware of it. A sample of 214 students from primary and secondary schools in the Corporate Area were chosen and given questionnaires to complete. Eighty-four of the children reported a history consistent with that of exercise-induced asthma and were further subjected to stress testing for a definitive diagnosis of this condition. A prevalence of 20.8% [C.I. +/- 5.35] was identified which reflected a rate comparable to that recorded in North America. There was a significantly higher prevalence in children of primary school ages, but all other variables considered for significance testing to determine associations between these and the prevalence of EIA proved not significant. A recommendation has been made for opportunity screening by medical practitioners.

Prevalence of exercise-induced asthma in schoolchildren in Kingston, St. Andrew and St. Catherine, Jamaica

A cross-sectional study was done, focusing on the prevalence of exercise-induced asthma in Jamaica and variables that may account for this rate. No previous study of this nature had been undertaken, and the investigators contend that there is a need to identify children who suffer from this condition but are unaware of it. A sample of 214 students from primary and secondary schools in the corporate area were chosen and given questionnaires to complete. Eighty-four of the children reported a history consistent with that of exercise-induced asthma and were further subjected to stress testing for a definitive diagnosis of this condition. A prevalence of 20.8 per cent [C.I ñ 5.35] was identified which reflected a rate comparable to that recorded in North America. There was a significantly higher prevalence in children of primary school ages, but all other variables considered for significance testing to determine associations between these and the prevalence of EIA proved not significant. A recomendation has been made for opportunity screening by medical practitioners

Use of peer role models to increase Pap smear and mammogram screening in Mexican-American and black women.

We evaluated the use of a community-based intervention model to increase Pap smear and mammogram screening in minority women. The community programs were based on the A Su Salud (To Your Health) model, which includes the presentation of positive role models in the media and positive social reinforcement by community volunteers. Mexican-American women 40-70 years of age in Corpus Christi, Texas, and black women 40-70 years of age in Galveston, Texas, were targeted. Role models from the target community told their personal stories about cancer screening through local media (television, radio, and newspapers). Volunteers reinforced media messages among the target audience by distributing newsletters. Preintervention and postintervention cross-sectional surveys among the target group measured relative increases in knowledge, attitude, and practice. Pap smear use (past two years) was not substantially improved. Mammogram use (past two years) increased 57% among Mexican-American women (prevalence rate ratio [PRR] = 1.57; 90% confidence interval [CI] = 1.19, 2.08) and 30% among black women (PRR = 1.30; 90% CI = 1.04, 1.63). We demonstrated the feasibility of implementing a peer role model intervention at the local health department level. The improvement in mammogram use among high-risk women is encouraging, but further controlled research is needed to test the effectiveness and cost-efficiency of this approach.

Perceptions and practices relating to condom use among urban men in Haiti.

This report is based on a survey conducted in 1986-87 of sexually active adult male residents in a low-income community of Port-au-Prince, Haiti. The objectives were to investigate knowledge of and attitudes toward condoms; to evaluate the effectiveness of the existing condom distribution program; and to obtain information that can be used in the design of strategies to increase condom acceptance and use among men throughout Haiti. A final sample of 706 sexually active adult male residents in stable unions, including a specially drawn sample of male partners of condom acceptors, were interviewed in their homes. Although condoms are almost universally known, they are rarely used. The majority felt that the responsibility for family planning should be borne by the woman. Whereas condoms may be of limited popularity for family planning purposes in Haiti, it should be determined whether they might be more acceptable as an effective means of controlling the spread of AIDS and other STDs.

PIP: Attitudes toward condom use and the effectiveness of a condom distribution program were investigated in a survey of 706 sexually active men residing in a low-income community in Port-au-prince, Haiti, in 1986-87. All respondents were in a stable sexual relationship at the time of the survey; 554 had received condoms (or their female partner had) from the Cite Soleil Family Planning Center, while the remaining respondents were recruited through a community sampling survey. The average age of study subjects was 33 years. 20% were married; the remaining men had been in a stable union for 8 years in the case of respondents recruited from the family planning center for 6 years in the case of men identified through the community survey. 25% of men in the former group and 15% of those in the latter group reported having had sexual relations with a person other than their regular partner in the 3 months preceding the interview. Although 99% of men in the community survey had heard of condoms, none had ever used this method; ever-use of any form of contraception was only 3% in this subsample. In contrast, 43% of men recruited from the family planning center had used condoms at some point and 5% were current users (contributing 13% of all current contraceptive use). 96% of ever-users of condoms reported that their female partner had obtained the method; however, only 10% states that their partner was influential in their decision to use condoms and only 2% agreed that the husband should take responsibility for pregnancy prevention. The low prevalence of condom use in this sample does not reflect opposition to family planning (93% supported the concept), concerns about efficacy (90% trusted the method), a perception that condoms are for casual sexual encounters (only 1% stated this opinion), or supply constraints. These findings indicate the need for an IEC campaign to promote more widespread condom use and male responsibility for family planning.

Eosinophilic meningoencephalitis due to Angiostrongylus cantonensis as the cause of death in captive non-human primates.

Fatal eosinophilic meningoencephalitis due to Angiostrongylus cantonensis is reported in captive non-human primates. A howler monkey (Alouatta caraya) at the Audubon Park and Zoological Gardens, New Orleans, LA, died 21 days after initial clinical symptoms. A white-handed gibbon (Hylobates lar) died at the Ardastra Gardens and Zoo, Nassau, Bahamas, 17 days after onset of symptoms. Both had access to free-ranging gastropods within the zoos. These are the first reported cases of natural infection by A. cantonensis in non-human primates in the western hemisphere.

Cactus alkaloids. XLVII. N alpha-dimethylhistamine, a hypotensive component of Echinocereus triglochidiatus.

Echinocereus triglochidiatus Engelm. var. neomexicanus (Standley) Standley ex W. T. Marshall is believed to cause psychotropic effects when consumed by the Mexican Tarahumara Indians. A phytochemical study was initiated with E. triglochidiatus Engelm. var. paucispinus Engelm. ex W. T. Marshall, which is more abundant in Texas. In the fractionated extracts three compounds, detected by thin-layer chromatography, were positive to Ehrlich's reagent, indicating the possible presence of indole alkaloids; however, a non-Erhlich positive alkaloid was crystallized as the dihydrochloride and subsequently identified (spectrometrically and via synthesis as N alpha, N alpha-dimethylhistamine dihydrochloride. The same compound was then detected chromatographically in the neomexicanus variety. This compound has peripheral hypotensive effects similar to histamine, and this action may help to explain the alleged psychotrophic effects of the cactus.

Cactus alkaloids XXXIII: beta-phenethylamines from the Guatemalan cactus Pilosocereus maxonii.

TLC analysis of extracts of Pilosocereus maxonii (Rose) Byles and Rowley detected six identifiable alkaloids. Preparative TLC aided in the crystallization of the hydrochlorides of N-methyl-3,4-dimethoxyphenethylamine, N-methyl-3-methoxytyramine, and N,N-dimethyl-3-methoxytyramine. Traces of 3,4-dimethoxyphenethylamine (TLC and mass spectrometry), tyramine (TLC), and N-methyltyramine (TLC) were identified. While all of these compounds were isolated and/or detected previously in other cactus species, this study is the first reported crystallization of N-methyl- and N,N-dimethyl-3-methoxytyramine from a natural source.