Do Subjective Alcohol Screening Tools Correlate with Biomarkers Among High-Risk Transgender Women and Men Who Have Sex with Men in Lima, Peru?

Alcohol abuse can influence sexual risk behavior; however, its measurement is not straightforward. This study compared self-reported alcohol use, via the AUDIT and CAGE, with levels of phosphatidylethanol (Peth), a phospholipid biomarker that forms with chronic, heavy drinking, among high-risk MSM and TW in Lima, Peru. Chi square, Fisher's exact, Wilcoxon ranksum tests compared the instruments. Receiver operating curves determined sensitivity and specificity of the self-reported measures. Among 69 MSM and 17 TW, PEth was positive for 86% (95% CI 77-93%) of participants, while 67% reported binge-drinking in the last 2 weeks. The AUDIT classified 25% as hazardous drinkers while CAGE identified 6% as problem drinkers. Self-reported binge drinking was more sensitive than the AUDIT for PEth positivity (71% vs. 27%, p = 0.022). Among high-risk MSM and TW in Lima, validated, self-report measures of alcohol abuse underestimated biological measures. Further research correlating bio-markers and self-reported alcohol abuse measures is needed.

Co-delivery of HIV pre-exposure prophylaxis (PrEP) and HIV testing among publicly insured adolescents and young adults (AYA) receiving medication for opioid use disorder (MOUD).

BACKGROUND: Low rates of HIV pre-exposure prophylaxis (PrEP) prescribing contribute to the disproportionate burden of HIV in the United States. Among adolescent and young adults (AYA) with opioid use disorder, HIV testing and PrEP co-prescription rates are poorly characterized. METHODS: We performed a retrospective analysis involving deidentified data from Philadelphia's Medicaid beneficiaries ages 16-29 years who were prescribed medication for opioid use disorder (MOUD) from 2015 to 2020 and continuously Medicaid-enrolled for ≥6 months prior to that prescription. After identifying the presence of a qualifying diagnosis signifying a PrEP indication, we examined the outcome of appropriate PrEP co-prescriptions and HIV testing using generalized estimating equations (GEE) modeling. RESULTS: We identified 795 AYA Medicaid beneficiaries with 1269 qualified treatment episodes. We calculated a PrEP prescribing rate of 29.47 per 1000 person-years among AYA receiving MOUD. The HIV testing rate was 63.47 per 1000 person-years among AYA receiving MOUD. GEE modeling revealed that individuals receiving methadone were more likely (aOR=2.62, 95% CI=1.06-6.49) to receive HIV testing within 6 months after a PrEP-qualifying diagnosis compared to those receiving other MOUD medications. Those who only saw outpatient behavioral health providers were less likely (aOR=0.48, 95% CI=0.24-0.99) to have received an HIV test within 6 months after the PrEP-qualifying diagnosis compared to those receiving inpatient behavioral health services. CONCLUSIONS: Co-prescription of PrEP and HIV testing among AYA receiving MOUD was rare in this large urban publicly insured population. Interventions are needed to increase HIV prevention services for this key population of AYA at risk for HIV infection.

Vascular Parameters for Ambulatory Monitoring of Congestive Heart Failure Patients: Proof of Concept.

PURPOSE: Prompt detection of congestion is an essential target in order to prevent heart failure (HF) related hospitalization, being ambulatory monitoring a promising strategy to do so. A successful non-invasive ambulatory monitoring system requires automatic devices for physiological data recording; these data must give information about HF deterioration early enough to predict HF-related adverse events. This work aims to evaluate seven vascular parameters for the ambulatory monitoring of congestive heart failure patients. METHODS: Seven vascular parameters are proposed as indicators of HF deterioration. These parameters are obtained using venous occlusion plethysmography; a technique that uses hardware able of being miniaturized and easily integrated into wearables for ambulatory monitoring. The ability of the proposed vascular parameters to detect congestion is evaluated in eight healthy volunteers and ten congestive heart failure patients with different congestion levels-mild, moderate and severe. RESULTS: Most parameters distinguish between healthy volunteers and heart failure patients, and some of them present significant differences between volunteers and low levels of congestion-mild or moderate. CONCLUSION: Home monitoring of some of the proposed parameters could detect HF deterioration on its onset and alert to health personnel.

Impact of alcohol use on sexual behavior among men who have sex with men and transgender women in Lima, Peru.

BACKGROUND: Alcohol use disorders (AUDs) may enhance the likelihood of risky sexual behaviors and the acquisition of sexually transmitted infections (STIs). Associations between AUDs with condomless anal intercourse (CAI) and STI/HIV prevalence were assessed among men who have sex with men (MSM) and transgender women (TW) in Lima, Peru. METHODS: MSM and TW were eligible to participate based on a set of inclusion criteria which characterized them as high-risk. Participants completed a bio-behavioral survey. An AUDIT score ≥8 determined AUD presence. Recent STI diagnosis included rectal gonorrhea/chlamydia, syphilis, and/or new HIV infection within 6 months. Prevalence ratios (PR) were calculated using Poisson regression. RESULTS: Among 312 MSM and 89 TW, 45% (181/401) had an AUD. Among those with an AUD, 164 (91%) were hazardous/harmful drinkers, and 17 (9%) had alcohol dependence. Higher CAI was reported by participants with an AUD vs. without, (82% vs. 72% albeit not significant). Reporting anal sex in two or more risky venues was associated with screening AUD positive vs. not (24% vs. 15%, p=0.001). There was no difference in recent STI/HIV prevalence by AUD status (32% overall). In multivariable analysis, screening AUD positive was not associated with CAI or recent STI/HIV infection. CONCLUSIONS: In our sample AUDs were not associated with CAI or new HIV infection/recent STI. However higher prevalence of CAI, alcohol use at last sex, and anal sex in risky venues among those with AUDs suggests that interventions to reduce the harms of alcohol should be aimed toward specific contexts.

Ultrasound-assisted extraction of phenolic compounds from strawberries prior to liquid chromatographic separation and photodiode array ultraviolet detection.

Ultrasound-assisted extraction was used for the determination of phenolic compounds present in strawberries. The optimization study of the extraction was carried out using spiked samples (100 mg/kg). The sample immersed in an aqueous solution containing hydrochloric acid (0.4 M) was sonicated for 2 min (duty cycle 0.2 s, output amplitude 20% of the nominal amplitude of the converter, applied power 100 W with the probe placed 1cm from the bottom of the water bath and 5 cm from the walls of the precipitate glass). Subsequent separation was carried out by liquid chromatography (LC) with photodiode array UV detection. Calibration curves using the standard addition in green strawberries typically gave linear dynamic ranges of 2-300 mg/l for all analytes; R(2) values exceeded 0.996 in all cases. The method was applied to two types of strawberries to demonstrate the applicability of the proposed method, which is much faster and produces less analyte degradation than methods as solid-liquid, subcritical water and microwave-assisted extraction.

[Recommendations for the prevention of respiratory syncytial virus infection]. / Recomendaciones para la prevención de la infección por virus respiratorio sincitial.

Premature babies < or = 35 weeks gestation, with or without chronic lung disease (CLD), and infants affected by severe congenital heart disease should be considered high risk population for RSV infection and hospitalization. Hygienic measures and RSV monoclonal antibodies (palivizumab) have been found useful in decreasing rates of RSV hospitalization in these patients. Guidelines for their administration include: a) strongly recommended use in premature babies < or = 28 weeks gestation, or born between 29-32 weeks gestation and less than 6 months at start of RSV station or discharged along it, or affected by CLD in treatment during last 6 months or by severe congenital heart disease. Last two groups could be prophylaxed for two RSV seasons. b) Recommended use among premature babies between 32-35 weeks gestation and less than 6 months of age and presenting two or more risk factors: chronologic age < 10 weeks at start of RSV station, breastfeeding < or = 2 months (physician prescription), sibling < 14 years old, day-care assistance, family history of wheezing, > or = 4 adults at home, airways malformation or neuromuscular disease.

Design, fabrication and metrological evaluation of wearable pressure sensors.

Pressure sensors are valuable transducers that are necessary in a huge number of medical application. However, the state of the art of compact and lightweight pressure sensors with the capability of measuring the contact pressure between two surfaces (contact pressure sensors) is very poor. In this work, several types of wearable contact pressure sensors are fabricated using different conductive textile materials and piezo-resistive films. The fabricated sensors differ in size, the textile conductor used and/or the number of layers of the sandwiched piezo-resistive film. The intention is to study, through the obtaining of their calibration curves, their metrological properties (repeatability, sensitivity and range) and determine which physical characteristics improve their ability for measuring contact pressures. It has been found that it is possible to obtain wearable contact pressure sensors through the proposed fabrication process with satisfactory repeatability, range and sensitivity; and that some of these properties can be improved by the physical characteristics of the sensors.

Enzyme inhibition-based biosensors and biosensing systems: questionable analytical devices.

An overview of methods based on enzyme inhibition is presented. Both biosensors and biosensing systems (implemented in continuous and discontinuous approaches) are considered. The aim of the overview is to alert users on the use of these devices which, despite they can involve selective biocatalysts, the inhibition effect is not selective. Tables and examples illustrate this assertion.

Study of the feasibility of focused microwave-assisted soxhlet extraction of N-methylcarbamates from soil.

A study of the feasibility of a focused microwave-assisted Soxhlet device for the extraction of N-methylcarbamates from soil has been performed. The main factors contributing to the extraction efficiency-namely microwave power, irradiation time and number of cycles--were optimized by means of a two-level full factorial design. The extracts were analysed by HPLC-post-column fluorescence derivatization-detection at excitation wavelength 340 nm and emission wavelength 445 nm. The method has allowed the extraction of carbamate pesticides from contaminated soil with quantitative recoveries, similar to those provided by the US Environmental Protection Agency method 8318, without degradation of the target compounds during the extraction and using less organic solvent, as 75-80% of the extractant was recycled.

Comparison of the effects of bischolylglycinatechloro-platinum(II) versus cisplatin on liver regeneration after partial hepatectomy.

BACKGROUND: Regional chemotherapy by intraportal administration has been envisaged as a useful strategy to prevent the high rate of recurrence after surgical removal of single liver tumors, even though it may inhibit liver regeneration. New cytostatic drugs, such as Bamet-H2-Na[Pt(cholylglycinate-O,N) (cholylglycinate-O) Cl]- have been developed to enhance the liver organotropism of antiproliferative agents. The aim of the present study was to compare the effects of Bamet-H2 and cisplatin on liver regeneration. MATERIALS AND METHODS: The ability of both drugs to inhibit liver cell proliferation was investigated using rat hepatocytes in primary culture. Two-thirds partially hepatectomized mice were used to measure the effects of glycocholic acid, cisplatin and Bamet-H2 on DNA synthesis by the regenerating liver in vivo. RESULTS: Up to 300 microM glycocholic acid, no effect on the growth of rat hepatocytes in primary culture was observed. By contrast, similar dose-dependent in vitro cytostatic effects of cisplatin and Bamet-H2 were found. No effect on mouse liver regeneration was found in animals receiving glycocholic acid. By contrast, both cisplatin and Bamet-H2 were found to induce a significant inhibition of DNA synthesis and slower recovery of liver mass. The effect of cisplatin was significantly stronger than that induced by Bamet-H2. Differences between these two compounds were also observed regarding the content of the drug in several tissues at short- and mid-term. Both drugs were highly concentrated in the liver and kidney, with minor distribution in other tissues at 8 hours after the last injection of the drug. However, Bamet-H2 was more efficiently eliminated from the body in 5 days. Moreover, higher toxicity and lower survival were observed in the group of animals treated with cisplatin as compared to Bamet-H2. CONCLUSIONS: Our results indicate that in agreement with the previously reported effects on several tumor cells lines, cisplatin and Bamet-H2 are similarly efficient as cytostatic drugs in liver cells when these are continuously exposed to the compounds in vitro. However, in the in vivo situation Bamet-H2 is better tolerated by the animals and induces less inhibition of liver regeneration than cisplatin. This is probably due to the enhanced biliary elimination of Bamet-H2.

In vitro cytostatic activity and DNA-interaction of the new liver organotropic complex chloro-bis-cholylglycinate-platinum (II).

BACKGROUND: The liver organotropic properties of the new bioinorganic complex of platinum (II) and glycocholic acid, Bamet-H2 have been reported previously. The aim of this work was to investigate the in vitro cytostatic activity of this compound. MATERIALS AND METHODS: The inhibition of cell growth and DNA synthesis by mouse leukemia L-1210 (mL), mouse hepatoma Hepa 1-6 (mH), rat hepatoma McA-RH7777 (rH) and human colon adenocarcinoma LS-174T (hCC) cells were measured. The effects on the electrophoretic mobility of the pUC18 plasmid, the DNA denaturation temperature and ethidium bromide (EthBr) binding to DNA were studied. RESULTS: A significant antiproliferative effect for Bamet-H2 was found (mH approximately hCC > mL approximately rH). DNA synthesis was also markedly inhibited (mH approximately hCC approximately mL approximately rH). Bamet-H2-induced a change in the electrophoretic mobility of pUC18 and the increase in DNA denaturation temperature suggested the existence of DNA-Bamet-H2 interactions. Scatchard plots obtained from EthBr displacement assays revealed that Bamet-H2 induces a reduction in both the number of DNA sites available and their ability to bind EthBr. CONCLUSION: Bamet H2 is able to interact with DNA, inhibit DNA synthesis, and hence reduce cell proliferation.

Parallel conductance estimation by hypertonic dilution method with conductance catheter: effects of the bolus concentration and temperature.

The conductance catheter has gained momentum since its introduction in cardiovascular dynamics back in 1980. However, measuring errors are still blurring its clinical acceptance. The main objective here was to study the effects of the injected saline concentration and temperature on the evaluation of the parallel conductance, Gp, and thus, on the correction volume Vp. That conductance, Gp, and its associated volume, Vp, were computed using 167 saline dilution curves obtained with boluses at different concentrations and temperatures, injected in seven anesthetized closed-chest dogs. The excursion of the total conductance relative to the steady-state value during a saline maneuver showed good correlation with the injected concentration at both studied temperatures. The reference parallel volume (one reference per dog) was defined as the average value obtained with three successive maneuvers, at 6-M concentration and at body temperature; therefore, the method acted as its own reference. The variation of Vp relative to the reference value was clearly dependent on the injected concentration and on its temperature; dispersion was greater at 22 degrees C than at 40 degrees C. The variability would recognize also other causes, such as uncertainty of the extrapolation procedure and the thoracic redistribution of electrical field lines. As conclusion, it is recommended to characterize each maneuver by its concentration and temperature. Body temperature and 6-M concentration appear as the most recommendable combination for the injectate in most animals. Finally, these results intend to characterize the Vp estimation procedure in order to minimize errors. The variability of Vp, in different experimental conditions, demonstrated that both concentration and temperature are additional parameters that may modify the Gp estimate.

Parallel conductance determination in cardiac volumetry using dilution manoeuvres: theoretical analysis and practical implications.

Left ventricular volume calibration based on the conductance catheter depends on the correct determination of the parallel conductance (Gp). Baan's saline manoeuvre procedure leads to Gp by finding the end-systolic (Ges) and end-diastolic (Ged) conductances, for each beat of the dilution curve rising limb. After plotting such values in an xy-system, their linear regression is back-projected to intersect the identity line, so yielding an estimated Gp. The objective is to theoretically analyse all possible lines, Ges = aGed + b (Baan's line) and, based on experimental results, to establish their limitations. This was attained by calculating the regression lines using, first Ged = f1(Ges) and thereafter, Ges = f2(Ged), which led to two values, Gp2 and Gp1, for the parallel conductance. The morphology of the saline curve was also modified to assess its effect on the extrapolation. Multiple dilutions were recorded in eight experimental dogs injecting different concentrations. Each curve was classified according to the maximum change (VAR) reached by the total average conductance. Over 138 manoeuvres, 276 regressions were processed yielding correlations higher than 0.65. Of this total, 92.4% gave positive parallel conductances. The rest produced negative values and, thus, were neglected. If the two (Ged, Ges) statistical relationships were ideal, they should yield Gp = Gp1 = Gp2; however, there were differences which, when Gp1 was studied against Gp2, led to: Gp1 = 0.97 Gp2 + 0.055, with r = 0.9476, and n = 85. The remaining 53 were discarded because either some Gp values were negative, or the correlation of Ges which Ged (or vice versa) was < 0.85, and/or VAR < 15%; the two latter conditions were found necessary for reliable calibration. Baan's line high correlation is not a unique condition to ensure the accuracy and precision of Gp determination because the slope a depends on VAR and, thus, different intersections with the identity line may be obtained. Its recommended that manoeuvres be used with at least eight data points, with VAR > 15% and, finally, with (Ges, Ged) correlation better than 0.85. Theoretical analysis of Baan's line offers a reference frame, which contains only a limited number of practical possibilities.

Electrical characterization of conductive textile materials and its evaluation as electrodes for venous occlusion plethysmography.

The ambulatory monitoring of biosignals involves the use of sensors, electrodes, actuators, processing tools and wireless communication modules. When a garment includes these elements with the purpose of recording vital signs and responding to specific situations it is call a 'Smart Wearable System'. Over the last years several authors have suggested that conductive textile material (e-textiles) could perform as electrode for these systems. This work aims at implementing an electrical characterization of e-textiles and an evaluation of their ability to act as textile electrodes for lower extremity venous occlusion plethysmography (LEVOP). The e-textile electrical characterization is carried out using two experimental set-ups (in vitro evaluation). Besides, LEVOP records are obtained from healthy volunteers (in vivo evaluation). Standard Ag/AgCl electrodes are used for comparison in all tests. Results shown that the proposed e-textiles are suitable for LEVOP recording and a good agreement between evaluations (in vivo and in vitro) is found.

Careers in biomedical engineering.

Although biomedical engineering was started in Argentina about 35 years ago, it has had a sustained growth for the last 25 years in human resources, with the emergence of new undergraduate and postgraduate careers, as well as in research, knowledge, technological development, and health care.