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In a previous study, we revealed a new way to modify multi-walled carbon nanotubes (MWCNTs) with 3,5-dinitrobenzoic acid (35DNB). Furthermore, we proved that a 35DNB-MWCNTGC electrode efficiently catalysed the oxidation of NADH. In this paper, with the aim of obtaining a stronger bond of the electrocatalytic mediator 35DNB with the MWCNTs, we have synthesized a modified compound of 35DNB. The modification consisted of adding a 4-(piren-1-yl)butyl terminal to 35DNB to form 4-(pyren-1-yl)butyl 3,5-dinitrobenzoate (35DNBpy). The synthesis of 35DNBpy was obtained with a yield of 78.3% (mp = 202–204 °C). With this change, we improved the electrocatalytic activity by several oxidation cycles, conferring electrocatalytic stability. The preparation and modification of electrodes with carbon nanotubes and 35DNBpy is fast and simple. The electrochemical study was performed by cyclic voltammetry in 3 mM NADH solutions. Oxidation of NADH occurs at 0.1 (V vs Ag/AgCl) in aqueous media at pH 7 and the same electrode can be used for up to 50 min. In this work, the electrocatalytic activity of new modified electrodes with MWCNTs and 35DNBpy is reported. The electrocatalytic activity was evaluated by cyclic voltammetry. The electrocatalytic capacity of the electrode and the heterogeneous electron transfer rate constant were calculated. Sensitivity of the modified electrode 35DNBpy/MWCNT/GCE is measured by voltammetric method which showed linear variation with NADH concentration with limit of detection (LOD) and sensitivity of 0.885 μM (3S/N) and 0.33 μA/μM, respectively.

In the scope of our studies tending to find new nanostructured electrodic platforms containing nitroaromatic compounds (NACs) capable of generating in situ electrocatalytic redox couples, we synthesized and electrochemically studied three related 4-(pyren-1-yl)-butyl-substituted nitrobenzoates (2-NBPy, 3-NBPy and 4-NBPy). The design of the compounds is based on a combination of a) an adsorptive tail (-butyl-pyrene) capable of interacting via π–π stacking with the MWCNT nanostructured electrodes and b) nitroaromatic compounds (NACs) capable of electrochemically activating to form a RNHOH/NO redox couple trapped on the nanostructured electrodic platform. Morphological and structural analyses of the nanostructured interfaces were performed by SEM and WAXS/SAXS analysis. All of the NBPy compounds trapped on the nanostructured electrodic platform were susceptible to reduction, generating the corresponding hydroxylamine derivative. The order of ease of reduction for the nitrocompounds is 4-NBPy > 2-NBPy > 3-NBPy. After electrochemical activation, all compounds generated an RNHOH/NO redox mediator couple with the following order of stability of the mediator couple: 2-NBPy > 3-NBPy > 4-NBPy. For the 2-NBPy and 3-NBPy derivatives, excellent stability of the couple was observed, and a decrease in the peak current of 6% was observed after 60 min.

In a conventional voltammetric experiment, the electroactive species is dissolved in solution, and then diffuses from the solution phase to the electrode phase. In our proposed non-conventional voltammetric experiment, the electroactive species is trapped in the electrode phase instead of being dissolved in solution. A non-aqueous solvent was first used to trap the organic species in a porous surface layer and the modified electrode then transferred to an aqueous buffer to conduct voltammetry measurements.We tested the non-conventional voltammetric mode using a modified multi-walled carbon nanotube electrode containing mono-, di- and tri-nitroaromatic compounds trapped in the porous three-dimensional network of the CNTs. From these experiments, we conclude that the non-conventional mode produces higher peak currents and displacement of the peak potentials, yielding lower overpotentials. Furthermore, it is possible to obtain more selective voltammograms in the non-conventional mode, showing peaks that could not be resolved in the conventional mode.These results are due to a change in the mass transport regime, with thin layer diffusion being the main transport method in the non-conventional mode, compared to semi-infinite diffusion in the conventional mode.The proposed approach is an excellent alternative for performing voltammetric studies on insoluble or slightly soluble organic compounds. Keywords: Non-conventional voltammetry, Nitrocompounds, Trapped nitrocompounds electrode, Thin layer diffusion, MWCNT

A novel type of multiwalled carbon nanotube-modified glassy carbon electrode with an entrapped nimesulide drug was constructed. The new electrode surface was characterized by scanning electrochemical microscopy and scanning electron microscopy. Additionally, using cyclic voltammetry, the electrochemical behaviour of nimesulide on the modified electrode was studied in detail, and this material was used as a sensor for the drug. The analytical parameters of this sensor were adequate, with a recovery value of 98.4% and detection and quantification limits of 1.6 nM and 5.5 nM, respectively. Finally, the developed sensor was applied successfully to determine the drug in commercial tablets. The method developed herein represents an unconventional way to perform voltammetry, where the electroactive species (nimesulide) is trapped in the electrode phase instead of dissolved in solution. This method is especially recommended for drugs that have low solubility in water.

In this work, we have both synthesized and studied 4-phenylbutyl-3,5-dinitrobenzoate (3,5-DNBPh) as a potential precursor of an electrocatalytic mediator for the oxidation of NADH, with the di-nitro compound immobilized in a three-dimensional network of glassy carbon electrodes modified with MWCNTs. This di-nitro compound is activated electrochemically to selectively generate one nitroso-hydroxylamine redox pair, which ultimately acts as a redox mediator of NADH oxidation. Thus, NADH electrocatalysis displaces the oxidation potential of NADH with the formation of a single voltammetric peak, the displacement occurs from Ep = + 0.374 V in GCE/MWCNT to + 0.001 V in GCE/MWCNT/3,5-DNBPh (very close to 0 V, ΔEp = 0.373 V). The 4-phenylbutyl-3,5-dinitrobenzoate mediator is sensitive to NADH concentration, and a linear regression between 0.1 and 0.6 mM NADH (r2 = 0.99) was obtained, with a detection limit of 22.3 μM (S/N = 3) and a quantification limit of 74.2 μM (S/N = 10). The developed modified electrode presents low NADH electrocatalytic oxidation potentials, and an interesting and novel advantage is that the preparation of the electrodes is fast, clean and effective, allowing biosensors to be obtained in a few steps.

We report that glassy carbon electrode (GCE) modified with multiwalled carbon nanotubes (MWCNTs) can encapsulate or entrap 3,5-dinitrobenzoic acid (35DNB) generating a 35DNB-MWCNTGC electrode. After electrochemical reduction in situ of only one nitro group of 35DNB, it turns into the hydroxylamine derivative (R-NHOH), which can be further oxidized to the nitroso derivative (R-NO). Then, R-NO/R-NHOH redox couple was electrogenerated in situ by cycling the potential between 0.20 and −0.20 V vs Ag/AgCl. The very well-defined and persistent redox couple was characterized with a formal potential, E o ’ = −28 mV vs Ag/AgCl at a scan rate of 20 mV s−1. Using the Laviron’s plot, a transfer coefficient, α = 0.45, and an electron transfer rate constant, k s = 10.5 s−1, for the electron transfer of the couple R-NO/R-NHOH, were calculated. This redox reaction results to be a very efficient mediator for electrocatalytic NADH oxidation. The 35DNB-MWCNTGC electrode efficiently catalyzes the oxidation of NADH with a decrease of more than 0.60 V vs Ag/AgCl in the overpotential compared to the bare GCE and a difference of 0.25 V vs Ag/AgCl with respect to the situation without mediator. The preparation of the electrode is very easy and not time-consuming.

OBJECTIVES/SPECIFIC AIMS: The Title V Cooperative Project between the University of Puerto Rico- Medical Sciences Campus (UPR-MSC) and Universidad Central del Caribe (UCC) has trained US, GS and F (participants) of HSPs to engage them in CTR. METHODS/STUDY POPULATION: First stage of the training sessions (TS) dealt with the theory of CTR. After TS and responding to their research interests, as answered in a questionnaire, the participants formed a CTMT, under the mentorship of a well-established CT researcher. This, as a prelude to their hands-on experiences in Intensive Development and Experiences in Advancement of Research and Increased Opportunities (IDEARIO), for which a research proposal is needed. RESULTS/ANTICIPATED RESULTS: Five (5) CTMTs were formed in different research areas – cardio, neuro, liver, renal, Zika–, as submitted in their research concept papers.Eight (8) CT researchers are currently mentoring 2 US, 7 GS and 6 F of HSPs through the CTMTs. They have submitted a research proposal, as a bridge between the theory in the TS and the practice in IDEARIO. Five (5) proposals were received and 2 of them approved, while the other 3 are in the evaluation process. We will present the composition, research topics, development of research and the feedback of participants in IDEARIO and CTMTs. DISCUSSION/SIGNIFICANCE OF IMPACT: The CTMTs and their respective proposals are effective strategies for the mentoring of US, GS and F in CTR.

One of the main challenges associated with the handling of carbon nanotubes (CNTs) for modifying electrodes is the production of adequate dispersions. We report the first example in which 1,3-dioxolane was used to produce dispersions of multiwalled carbon nanotubes (MWCNTs) to modify glassy carbon electrodes (GCE). The films of MWCNTs obtained after evaporation were characterised by scanning electron microscopy (SEM) and adsorptive stripping voltammetry (ASV). 1,3-Dioxolane, a green solvent that is nontoxic, odourless and environmentally friendly, produces nanotube dispersions that leaves no residue on the resulting electrode when it evaporates. Keywords: MWCNT, MWCNT dispersion, 1,3-Dioxolane, Modified electrode

OBJECTIVES/SPECIFIC AIMS: The Title V Cooperative Project of the UPR-MSC and UCC has demonstrated that educational interventions in CTR are very effective in fulfilling the objective of promoting awareness, stimulate interest and increase the knowledge, skills and opportunities, to US, GS and F (participants) in CTR. METHODS/STUDY POPULATION: The training sessions (TS) offered through the Title V initiative have become an engine for the involvement in CTR for participants from higher education institutions island-wide. TS consisted of cycles –level 1 and 2–: Research Education Towards Opportunities (RETO,I,II) and Mentorship Offering Training Opportunities for Research (MOTOR,I,II), ending in the formation of the Clinical and Translational Mentoring Teams (CTMT)s, in which participants, paired by their research interests, were mentored by a well-established CT researchers in their research project, to be developed in the Intensive Development and Experiences in Advancement of Research and Increased Opportunities (IDEARIO). RESULTS/ANTICIPATED RESULTS: Up to date, 4 TS-level 1 and 2 TS-level 2 were offered. Eighty (80) participants completed level 1, distributed: 42 (52.5%) US in RETO, 21 (26.25%) GS and 17 (21.25%) F in MOTOR and 17 participants completed level 2, distributed: 4 (23.52%) US in RETO, 6 (25.29%) GS and 7 (41.17%) F in MOTOR. From which, 15, with 8 CT researchers, formed 5 CTMTs in different research areas – cardio, neuro, liver, renal, Zika–. DISCUSSION/SIGNIFICANCE OF IMPACT: US, GS and F were integrated in the active process throughout educational levels for their development in CTR.

The cyclic voltammetric behavior of 3,5-dinitrobenzoic acid (3,5-DNB) in 0.1 M PBS of pH 7 was examined at a glassy carbon electrode (GCE). 3,5-DNB was found to produce two irreversible reduction peaks corresponds to the reduction of each nitro group in the 3,5-DNB molecule. Our results contradict previous studies (P.Gopal et al. Journal of Molecular Liquids 178 (2013) 168-174) wherein the same peaks are assigned as, the first, to the reduction of the nitro group to hydroxylamine and the second, to the subsequent reduction to amine derivative. Also we report that GCE modified with multiwalled carbon nanotubes (MWCNTs) can be derivatized with 3,5-DNB. The derivatization procedure involves simple immersion of the MWCNT-modified electrode in a solution containing 3,5-DNB. SEM images reveals that the network of nanotubes form a homogeneous, twisted, densely packed, three-dimensional array that remains attached to the GCE surface. Both electrochemical and SEM measurements indicate that 3,5-DNB is encapsulated on the electrode, most probably by being trapped within the pockets of the mentioned three-dimensional array, without formation of covalent bonding.

Cyclic voltammetry (CV) is a very useful electrochemical tool used to study reaction systems that include chemical steps that are coupled to electron transfers. This type of system generally involves the chemical reaction of an electrochemically generated free radical. Published methods exist that are used to determine the kinetics of electrochemically initiated chemical reactions from the measurements of the peak current ratio ( i pa / i pc ) of a cyclic voltammogram. The published method requires working curves to relate a kinetic parameter to the peak current ratio. In the presented work, a digital simulation package was used to obtain improved working curves for specific working conditions. The curves were compared with the published results for the first- and second-order chemical reactions following the charge transfer step mechanisms. According to the presented results, the previously published working curve is reliable for a mechanism with a first-order chemical reaction; however, a change in the switching potential requires a recalculation of the curve. In the case of mechanisms with a second-order step (dimerisation and disproportionation), several different views exist on how the second-order chemical term should be expressed so that different values of the constant are obtained. Parameters such as electrode type, electrode area, electroactive species concentration, switching potential, scan rate and method for peak current ratio calculation modify the working curves and must always be specified. We propose a standardised method to obtain the most reliable kinetic constant values. The results of this work will permit researchers who handle simulation software to construct their own working curves. Additionally, those who do not have the simulation software could use the working curves described here. The revelations of the presented experiments may be useful to a broad chemistry audience because this study presents a simple and low-cost procedure for the study of free radicals that otherwise should be studied with more sophisticated and expensive techniques, such as ESR or pulse radiolysis.

BACKGROUND: To assess the need for cultural tailoring of an effective sexual health middle school curriculum, “It's Your Game: Keep It Real” (IYG), prior to implementation in Puerto Rican (PR) middle schools. METHODS: Seventy-three seventh-grade bilingual students participated in IYG curriculum activities (both group-based and computer-based) in two 2-hour testing sessions in spring 2008. Rating scales of acceptability, understandability, credibility, ease of use, and motivational appeal and qualitative feedback via open-ended responses and group process provided insight into needed surface and deep structure cultural tailoring. RESULTS: Students rated IYG highly on cultural tailoring and motivational parameters and were highly engaged by the lesson content. School personnel rated IYG as a feasible strategy for use in PR middle schools. While surface cultural elements (eg, characters, attire, body language) were identified as important foci for adaptation, content related to deeper cultural elements such as core behaviors, risky situations, attitudes, and specific skills were considered as relevant to PR youth as to their US counterparts. CONCLUSION: Effective human immunodeficiency virus, sexually transmitted disease, and pregnancy skills training prevention programs such as IYG that are developed for minority US youth may offer a feasible option for international implementation when extensive cultural adaptation is not a viable option.

OBJECTIVES/SPECIFIC AIMS: The University of Puerto Rico-Medical Sciences Campus and Universidad Central del Caribe, through the Title V Cooperative Project, devised a clinical and translational research (CTR) platform to pipeline students/faculty of undergraduate health sciences programs into CTR. Educational interventions in CTR—introductory intervention (II) and Annual Symposium (AS)—were designed to promote awareness, stimulate interest of students and faculty in CTR. METHODS/STUDY POPULATION: In the II the participants (n=159) were surveyed before and after a presentation and panel discussion about CTR. In addition, after the sessions—plenary, panel, and workshop—about CTR, the participants of AS (n=42) were surveyed for satisfaction and learning experience in CTR. RESULTS/ANTICIPATED RESULTS: Most participants of the II, 134 (84.3%) were students. In total, 58 (58, 36.5%) completed the post II survey. Of these, 53.4% satisfactorily defined the CTR concept Versus only 31.0% that could define CTR in the pre survey, 47 (81.7%) were unable to identify a CTR researcher and 45 (78.3 %) expressed interest in learning about CTR. In total, 28 (28, 66.7%) participants of the AS completed the satisfaction survey, out of which 17 (60.6%) were students. One hundred percent (100%) agreed that the AS served as a vehicle to increase their knowledge in CTR. DISCUSSION/SIGNIFICANCE OF IMPACT: The educational interventions demonstrated to be an effective strategy to promote awareness and stimulate interest of students and faculty in CTR. In addition, the results obtained, provided valuable baseline information for the planning—development of training cycles in CTR.

OBJECTIVES/SPECIFIC AIMS: Responding to the need and interest of students and faculty of the UHSP in learning about CTR, the Title V Cooperative Project between UPR-MSC and UCC, developed and offered a training cycle (TC) in CTR. METHODS/STUDY POPULATION: Undergraduate students (US), undergraduate faculty (UF), and graduate students (GS) were invited to register in: Research Education Towards Opportunities (RETO) and Mentorship Offering Training Opportunities for Research (MOTOR), which consisted of 20 hours of training in CTR, with interdisciplinary sessions in: Introduction and preparation of a presentation in CTR; Identify, interview and share a presentation of a CT researcher; participation in conferences and a summer camp in CTR. At the end of the TC, surveys—satisfaction and needs assessment—for training in CTR were administered. RESULTS/ANTICIPATED RESULTS: Thirty-three (33) registered in the TC, distributed: 13 (39.39%) US in RETO, 12 (36.36%) GS and 8 (24.24%) UF in MOTOR. Of these, 25 (75.75%) answered and submitted the on-line surveys and received a completion certificate. All (100%) were satisfied with the TC, and for 96% of the respondents, their expectations were fulfilled, and will continue in the TC. They selected critical review, scientific communication, and cultural diversity as thematic areas of interest. In addition, 60% of them selected neuroscience, cancer and medical imaging as main research areas of interest. DISCUSSION/SIGNIFICANCE OF IMPACT: The TC demonstrated to be an effective strategy to provide new knowledge, experiences, and interest in CTR. It also established a pathway for future engagement in CTR.

The objective of this study was to determine the association between binge drinking and violence in a representative sample of secondary-school students in Puerto Rico.Consulta Juvenil VII (a biennial survey of school-aged youths in Puerto Rico) has a representative sample of adolescent students in Puerto Rico. A multi-stage stratified cluster sampling design was used. The sampling frame of Consulta Juvenil VII includes all the public and private schools registered with the Department of Education and the Council of General Education in Puerto Rico. The study utilizes a self-administered questionnaire that was translated and adapted from the "Student Survey of Risk and Protective Factors and Prevalence of Alcohol, Tobacco, and Other Drug Use". "Binge drinking" was defined as having 5 or more alcoholic drinks in a row during the 30 days preceding the survey.Almost 20% of the sample members reported that at least 1 instance of binge drinking had taken place during the 2 weeks prior to the survey (17.7%). After controlling for gender, age, school level, the type of system, and the parents' educational levels, the odds of a given binge drinker reporting violent behaviors were 5 times greater than the odds among non-binge drinkers (OR: 5.6; 95% CI: 4.7-6.7).The study shows an association between binge drinking and violence in Puerto Rican adolescents, indicating that Hispanic youths who abuse alcohol may be at increased risk of violence. These findings suggest that violence prevention programs should be integrated with substance use prevention programs. [PR Health

South American camelids are dribble ejaculators, and urethral contractions occur throughout copulation, which may last 25 min. The urethral contractions and their association with semen characteristics during copulation were determined in llamas and alpacas. A transrectal probe was held in the rectum of the male while copulating an artificial vagina, which was accessed underneath the dummy through a hole. The semen-collecting tube was changed every 5 min. Semen characteristics, color, volume, consistency, motility, concentration, and percentage of live sperm were determined at 5-min intervals. Urethral contractions were evenly distributed during copulation: 40 in alpacas and 63 in llamas (p.05), with a general range of 11 to 132. Semen color was milky in 63%, and translucent in 36.5% for alpacas; and creamy (9.9%), milky (47%), and translucent (42%) for llamas. The mean volume of ejaculate was 0.3, 0.4, 0.6, 0.7, 0.6, 0.8, 0.3, and 3.0 mL for 5, 10, 15, 20, 25, and 30 min, respectively. Semen consistency was variable: viscous (65%) and semiviscous (34%) in alpacas; and viscous (57%) and semiviscous (42%) in llamas. Spermatic motility varied between 60 and 80% for the llama, and 40 and 80% for the alpaca. Spermatic concentration varied between 60 and 188 x 10(3)/mm3 in llamas, and 30 and 170 x 10(3)/mm3 in alpacas. Percentage of live sperm varied the least: 81 to 90% in llamas and 65 to 90% in alpacas. The ejaculate of llamas and alpacas is not fractionated, urethral contractions are evenly distributed, during copulation, and semen characteristics are present throughout the copulatory period.

We report a voltammetric study of several nitroaromatic compounds such as the drugs: Nifedipine, Nitrendipine, Furnidipine and Nisoldipine in multiwalled carbon nanotubes (MWCNT) modified electrodes. All the compounds are strongly encapsulated in the three dimensional structure of the MWCNT and then reduced to the corresponding hydroxylamine derivatives. In the case of the modified electrode with MWCNT the answer in current are remarkably increased (approximately 40 times). This current multiplier effect is due to the nitro compounds are not only superficially adsorbed but this really encapsulated in the nanotube network covering the GCE. The nitro reduction peak was linearly dependent with the concentration of the nitroaromatic compound with detection limit (LOD) of 1.2·0-8 mol•L-1 and a quantification limits (LOQ) of 3.9•10-8 mol•L-1 for the case of Nitrendipine. All the studied nitrocompounds followed equivalents behaviours. Obviously from this result it is possible to postulate this technology as a very useful tool to develop analytical methods to determine these nitroaromatic drugs in real samples such as biological fluids. From the obtained results it is possible to conclude that for the studied 1,4-dihydropyridine-4-nitrobenzene substituted compounds a greater difficulty of reduction implies a greater ability to encapsulation.

Item does not contain fulltext BACKGROUND: The effect of intensified platelet inhibition for patients with unstable angina or myocardial infarction without ST-segment elevation who do not undergo revascularization has not been delineated. METHODS: In this double-blind, randomized trial, in a primary analysis involving 7243 patients under the age of 75 years receiving aspirin, we evaluated up to 30 months of treatment with prasugrel (10 mg daily) versus clopidogrel (75 mg daily). In a secondary analysis involving 2083 patients 75 years of age or older, we evaluated 5 mg of prasugrel versus 75 mg of clopidogrel. RESULTS: At a median follow-up of 17 months, the primary end point of death from cardiovascular causes, myocardial infarction, or stroke among patients under the age of 75 years occurred in 13.9% of the prasugrel group and 16.0% of the clopidogrel group (hazard ratio in the prasugrel group, 0.91; 95% confidence interval [CI], 0.79 to 1.05; P=0.21). Similar results were observed in the overall population. The prespecified analysis of multiple recurrent ischemic events (all components of the primary end point) suggested a lower risk for prasugrel among patients under the age of 75 years (hazard ratio, 0.85; 95% CI, 0.72 to 1.00; P=0.04). Rates of severe and intracranial bleeding were similar in the two groups in all age groups. There was no significant between-group difference in the frequency of nonhemorrhagic serious adverse events, except for a higher frequency of heart failure in the clopidogrel group. CONCLUSIONS: Among patients with unstable angina or myocardial infarction without ST-segment elevation, prasugrel did not significantly reduce the frequency of the primary end point, as compared with clopidogrel, and similar risks of bleeding were observed. (Funded by Eli Lilly and Daiichi Sankyo; TRILOGY ACS ClinicalTrials.gov number, NCT00699998.).

We report that GCE modified with MWCNTs can be derivatized by the nitroaromatic drug nitrendipine (NTD) ((RS)-ethyl methyl 2,6-dimethyl-4-(3-nitrophenyl)-1,4-dihydropyridine-3,5-dicarboxylate) simply by dipping the electrode in a solution of 0.1 M Britton–Robinson buffer containing 0.1 mM NTD (pH 2) for 4 min at open circuit. The derivatized electrode is thus reduced, producing the corresponding hydroxylamine derivative-modified electrode, which can be further oxidized to the nitroso derivative. A stable nitroso/hydroxylamine derivative couple appears if the modified electrode is conveniently cycled. With proper selection of the adequate potential, the derivatized electrode can be modified as nitroso or hydroxylamine derivatives. Keywords: Nitroaromatic modified electrode, MWCNT, Nitrendipine, Derivatization

The electrochemistry of 2,2-dimethyl-(3H)-3-(N-3'-nitrophenylamino)naphtho[1,2- b]furan-4,5-dione ([Q]-PhNO2), on mercury was investigated. The first peak is consistent with a quasi-reversible one-electron reduction of the ortho-quinone, forming [Q•-]-PhNO2, while the second one, bielectronic, corresponds to the simultaneous reduction of the latter radical to a dianion and the nitro group to a nitro radical anion. The second order rate constant, k disp, for the decay of [Q•-]-PhNO2 is 15.188 x 10³ ± 827 mol"1 L s"1 and the t1/2 equals 0.06 s. E¹7Ic values for [Q]-PhNO2 and its precursor, nor-β-lapachone, are similar. The ease of semiquinone generation and its stability are parameters statistically relevant in the correlation biochemical/theoretical aspects.

To describe the services delivered by the Family Medicine Physicians at a Community Health Center.All information from patient visits during the natural year 1996 were registered using a commercialized computer program. The information was gathered by different means: initial interview, physician's report, records, and personal interviews.A total of 13,203 visits were registered; this represent a total of 4,493 patients. Most of the patients were women, and with a mean age of 38. As expected, most of the patients have Medicaid. The most common conditions seen were hypertension, diabetes, and respiratory diseases. The mean number of visits during the year for almost all conditions was three. Most of the children and adolescents visit the Center due to respiratory conditions, while adults come due to hypertension, diabetes, and musculoskeletal conditions.

Identify several HIV risk behaviors among adolescent students.The sample (n = 3,648) was selected using a two-staged stratified cluster sampling design, and weighted to represent all junior high and high school students.About 28.8% of the students reported ever having sexual activity. Less than half of the sexually active (44.5%) used condoms during their last sexual activity; 27.6% used them always. Only 54.7% knew correctly75% of the HIV knowledge questions. A HIV risk scale was constructed using five risk factors. About 15.9% of the students did not have any risk factor, 36.2% had one, 47.9% had two or more. Males and high school students had significantly more risk factors. Half of the students will abstain from having sex next year because they don't want to get HIV/AIDS.It is important to implement effective HIV prevention programs for adolescents in order to change their attitudes and behaviors.

The electrochemical reduction of l-methyl-4-nitro-2-carboxyimidazole (RNO 2 COOH) in a nonaqueous medium produced two reduction signals, which were influenced by the dissociation of the compound. The first reduction signal was caused by the reduction of the acidic species, and the second signal was a quasi-reversible couple caused by the reduction of the conjugate base to the radical dianion. According to the theory developed by Nicholson for the study of the electrode reaction kinetics, we have obtained the heterogeneous rate constant, k° = (9.74 ± 0.052) X 10 -3 cm s -1 , for the reduction of the conjugate base to the radical dianion. The voltammetric behavior of RNO 2 COOH and its comparison with the behavior of another related compound such as 1-methyl-4-nitro-2-hydroxymethylimidazole is a good example to show the applicability of the general theory about the mechanism of self-protonation reactions in organic electrochemical processes to the specific case of nitroimidazole derivatives. According to the presented results, the presence of acidic hydrogen as a substituent in the nitroimidazole moiety would permit the modulation of the nitro radical anion stability, thus affecting its potential biological activity.

The distribution and character of Tertiary magmatism in the non-volcanic region of shallow subduction between 28°S and 33°S in the Andes correlates with other geological and geophysical evidence suggesting that the subduction zone in this region has shallowed over the last 18 Ma with a major change occurring between 11 and 8 Ma. Geologic and geochemical data suggest that the magmatic source region under the Chilean Cordillera (29.0–30.5°S) changed at 16–18 Ma from garnet-poor to garnet-rich coincident with cooling due to shallowing of the subduction zone and thickening of the crust. Magmas older than 16–18 Ma appear to have fractionated at shallower crustal levels and interacted less with the pre-existing crust than have younger magmas. Except for small silicic ignimbrites, volcanism ended in the Cordillera at about 11 Ma. Magmatic activity spread to east to the Calingasta Valley and Precordillera in Argentina between 18 and 7 Ma (exact ages uncertain) as the subduction zone shallowed. The chemistry of the andesitic to rhyolitic composition rocks in this region are consistent with derivation from a thickened crust over a shallowing subduction zone. After 8 Ma, the principal magmatic activity migrated far to the east to the Pocho (7.8-4.9 Ma) and San Luis regions in the Sierras Pampeanas. The volcanic rocks (54–70% SiO2) in this area are geochemically distinct from recent volcanic rocks in other parts of the Andes, but are consistent with eruption over a deep segment of the seismic zone. Present-day volcanism in the “flat slab” region is lacking in the west due to insufficient heat for melting in the mantle above the slab, and in the east because the slab has already lost the components to flux melting in the mantle above the slab by the time temperatures are high enough to produce melting.

In the mid-late Tertiary (27–6 m.y. ago), volcanism diminished, then ceased in the main Andean Cordillera in Chile between 29° and 30°30′S. Over the same time span the subduction angle shallowed under this region, which today lies in the modern shallowly dipping, nonvolcanic segment of the south central Andes (28°–33°S). The trace and major element chemistry and mineralogy of the volcanic rocks in this region record the detailed pattern of lithospheric cooling and crustal thickening that accompany this major tectonic transition. Volcanic changes include, in addition to a decreased rate of volcanism, a decrease in the range of compositions from basaltic andesites to rhyolites in the oldest rocks to only rhyolite in the youngest rocks, a change in source and fractionating mineralogy with an increased role for amphibole and garnet in the younger rocks, and an increase in crustal assimilation. These volcanic changes also correlate in time with deformational events that help to account for crustal thickening and the space-time pattern of deformation and volcanism in the foreland region. Although the model stands alone, support for the tectonic setting and magmatic source region of these Tertiary volcanic rocks can be found in comparisons with recent volcanic rocks erupting over more steeply dipping modern Andean segments. The older Dona Ana Formation (27–18 m.y.) is similar to volcanic rocks in the Southern Volcanic Zone, while the younger Cerro de las Tortolas (14–10 m.y.) and Vallecito (6 m.y.) formations are similar to volcanic rocks over regions of thicker crust in the Central Volcanic Zone and the northern part of the Southern Volcanic Zone.

AIMS: This report describes the baseline characteristics of patients in the Reduction of Events with Darbepoetin alfa in Heart Failure trial (RED-HF) which is testing the hypothesis that anaemia correction with darbepoetin alfa will reduce the composite endpoint of death from any cause or hospital admission for worsening heart failure, and improve other outcomes. METHODS AND RESULTS: Key demographic, clinical, and laboratory findings, along with baseline treatment, are reported and compared with those of patients in other recent clinical trials in heart failure. Compared with other recent trials, RED-HF enrolled more elderly [mean age 70 (SD 11.4) years], female (41%), and black (9%) patients. RED-HF patients more often had diabetes (46%) and renal impairment (72% had an estimated glomerular filtration rate < 60 mL/min/1.73 m2). Patients in RED-HF had heart failure of longer duration [5.3 (5.4) years], worse NYHA class (35% II, 63% III, and 2% IV), and more signs of congestion. Mean EF was 30% (6.8%). RED-HF patients were well treated at randomization, and pharmacological therapy at baseline was broadly similar to that of other recent trials, taking account of study-specific inclusion/exclusion criteria. Median (interquartile range) haemoglobin at baseline was 112 (106-117) g/L. CONCLUSION: The anaemic patients enrolled in RED-HF were older, moderately to markedly symptomatic, and had extensive co-morbidity. Fil: McMurray, John J. V.. University of Glasgow; Reino Unido Fil: Anand, Inder S.. University of Minnesota; Estados Unidos Fil: Diaz, Rafael. Estudios Clínicos Latinoamérica; Argentina Fil: Maggioni, Aldo P.. Associazione Nazionale Medici Cardiologi Ospedalieri; Italia Fil: O'Connor, Christopher. University of Duke; Estados Unidos Fil: Pfeffer, Marc A.. Brigham and Women’s Hospita; Estados Unidos Fil: Solomon, Scott D.. Brigham and Women’s Hospital; Estados Unidos Fil: Tendera, Micha. Medical University of Silesia; Polonia Fil: van Veldhuisen, Dirk J.. University of Groningen; Países Bajos Fil: Moetaz, Albizem. Amgen Inc.; Estados Unidos Fil: Cheng, Sunfa. Amgen Inc.; Estados Unidos Fil: Scarlata, Debra. Amgen Inc.; Estados Unidos Fil: Swedberg, Karl. University of Gothenburg; Suecia Fil: Young, James B.. Cleveland Clinic. Endocrinology and Metabolism Institute; Estados Unidos Fil: Toblli, Jorge Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: RED-HF Committees Investigators. No especifíca