Where's the BIPOC Blueprint for Healthy Youth Development? The Role of Scientific Omissions in Our Struggle for Science Translation and Racial Equity in the United States

Prevention Science seeks to advance the prevention research and to translate scientific advances into the promotion of healthy development for all youth. Despite tremendous progress creating a robust evidence-base and set of translational tools, elaborations and expansions for equity are required. Our collective errors of omission as prevention researchers have left prevention practitioners and policy-makers without sufficient information to identify strategies that have been demonstrated to prevent behavioral health problems in young people who identify as Black, Indigenous, or other People of Color (BIPOC). We first describe the current shortcomings of available evidence, and then we call for individual and collective action to conceptualize equity-enhancing prevention, sample more inclusively, and improve analytic approaches such that we can truly promote the healthy development of all youth.

A phenomenological, intersectional understanding of coping with ageism and racism among older adults

The aim of this qualitative, phenomenological study was to understand how older adults cope with experiences of ageism and racism through an intersectional lens. Twenty adults 60+ residing in the U.S. Mountain West who identified as Black, Hispanic/Latino(a), Asian-American/Pacific Islander, Indigenous, or White participated individually in a one-hour, semi-structured interview. A team of five coders engaged in an inductive coding process through independent coding followed by critical discussion. Peer debriefing enhanced credibility. Nine themes were organized by three umbrella categories: Coping with ageism: 1) distancing via self-determination/defying stereotypes, 2) distancing by helping others; Coping with racism: 3) resistance, 4) exhaustion; Coping with both ageism and racism: 5) increased awareness through aging, 6) healthy lifestyle, 7) education, 8) acceptance/ 'let it go', and 9) avoidance. Novel findings include how older adults may cope with ageism and racism via increased awareness through aging and with ageism specifically by helping peer older adults, although instances of internalized ageism were noted and discussed. The themes exemplify problem-focused (e.g., helping others) and emotion-focused (acceptance), as well as individual (e.g., self-determination) and collective (e.g., resistance) coping strategies. This study can serve as a resource for practitioners in applying a more nuanced understanding of the ways older adults cope with ageism and racism in later life.

Identifying Root Causes: Evaluation of a Program to Engage Youth in a Social Justice Approach to Tobacco Control

Movements designed to engage youth in tobacco control have been an important part of tobacco prevention for decades. Today, young people are increasingly diverse, and their primary issues of concern are gun control, racism, mental health, and climate change. To engage today's young people, tobacco control programs need to draw connections between youth's identities, top issues, and tobacco. UpRISE is a social justice youth tobacco control movement that engages diverse youth in identifying the root causes of youth nicotine use. In 2018-2019, 21 youth-serving organizations and schools hosted youth coalitions. Coalitions engaged in a six-session workbook called "Getting to the root cause," and adults were provided training and reflective supervision. Pre/post surveys with youth participants (n = 180) and end-of-year interviews with adult facilitators (n = 22) were used to assess outcomes. The primary outcomes were supportive adult relationships, youth voice in decision-making, anti-tobacco industry attitudes and beliefs, psychological empowerment, critical consciousness, and global belief in a just world. Quantitative measures of supportive adult relationships, youth voice in decision-making, psychological empowerment, and anti-tobacco industry attitudes and beliefs all increased significantly over time (p < .0001, p < .0001, p < .0001, p = .0034, respectively). Critical consciousness and global belief in a just world did not change significantly. During interviews, adults reported learning how: to engage in youth-adult partnerships, the tobacco industry abused its power, to engage in critical reflection about power. Adults also felt empowered. UpRISE may be a promising approach to increase racially diverse youth's engagement in social justice-oriented tobacco control efforts that advance equity.

Psychological impact after treatment in patients with head and neck cancer

BACKGROUND

Cancer is the second cause of death all over the world and it causes considerable morbidity, disability, and treatment sequela, which often lead to post-treatment pain and disfigurement. This study aims to evaluate such physical sequelae, and their psychological, (cognitive and emotional), impact, in a cohort of patients treated for Head and Neck (HNC) cancer, in search for methods to help such patients deal effectively with the psychological effects of their cancer treatments adverse consequences.

MATERIAL AND METHODS

The sample consists of 56 subjects, 47 men and 9 women, ranging from 47 years to 86 years of age, who were treated for head and neck cancers at Spanish Public General Hospital in the Otolaryngology Unit, Surgery Section. Two types of questionnaires were used in the study: the Questionnaire of Sequelae after Treatment of head and neck carcinoma and the State-Trait Anxiety Inventory (STAI-E and R).

RESULTS

With respect to anxiety, the study found high levels of state anxiety which was significantly associated with the degree of perception of social stigma but was not associated with the post-treatment sequelae themselves nor with the level of discomfort that such symptomatic sequelae produced. The presence of a post-surgical stoma with cannula, increased patient's stigma (both components: external rejection and self-rejection) and state anxiety ratings, while there was no difference in state anxiety between cannulated and non-cannulated patients. There are few differences between men and women in terms of the presence of anxiety and their responses are similar in terms of the after-effects of surgery.

CONCLUSIONS

Our study confirmed that current treatments for Head and Neck carcinoma generate adverse symptomatic sequela that impose significant psychological and physical burden for these patients. We will discuss the various pathways for preventive intervention that these findings open up.

A Phenomenological Understanding of the Intersectionality of Ageism and Racism Among Older Adults: Individual-Level Experiences

OBJECTIVES

Ageism is a prevalent, insidious social justice issue which has harmful effects on the health of older adults. Preliminary literature explores the intersectionality of ageism with sexism, ableism, and ageism experienced among LGBTQ+ older adults. Yet, the intersectionality of ageism with racism remains largely absent from the literature. Therefore, this study explores the lived experience of the intersectionality of ageism and racism among older adults.

METHODS

This qualitative study applied a phenomenological approach. Twenty participants 60+ years of age (M=69) in the U.S. Mountain West identifying as Black, Latino(a), Asian-American/Pacific Islander, Indigenous, or White engaged in a one-hour interview between February and July 2021. A three-cycle coding process applied constant comparison methods. Five coders independently coded interviews, engaging in critical discussion to resolve disagreements. An audit trail, member checking, and peer debriefing enhanced credibility.

RESULTS

This study focuses on individual-level experiences exemplified by four umbrella themes and nine sub-themes. The umbrella themes are: 1) racism experienced differently based on age, 2) ageism experienced differently based on race, 3) comparing/contrasting experiences of ageism and racism, and 4) "othering" or discrimination.

DISCUSSION

The findings indicate how ageism may be racialized through stereotypes such as mental incapability. Practitioners can apply the findings to enhance support for older adults by designing interventions aimed at reducing racialized ageist stereotypes and increasing collaboration through education across anti-ageism/anti-racism initiatives. Future research should focus on the impacts of the intersectionality of ageism and racism on specific health outcomes in addition to structural-level interventions.

EXPLORING THE LIVED EXPERIENCE OF RACIALIZED AGEISM AMONG OLDER ADULTS: A PHENOMENOLOGICAL STUDY

Ageism is a prevalent, insidious social justice issue which has harmful effects on the health of older adults. Preliminary literature explores the intersectionality of ageism with sexism, ableism, classism, and ageism experienced among LGBTQ+ older adults. To our knowledge, the intersection of ageism with racism, or racialized ageism, is largely absent from the literature. This qualitative study explored the following research question from a phenomenological perspective: “What is the lived experience of racialized ageism among diverse older adults?” Twenty participants 60+ years of age (M=69) in the U.S. Mountain West identifying as Black, Latino(a), Asian-American/Pacific Islander, Indigenous, or White engaged in a one-hour interview between February and July 2021. A three-cycle coding process used constant comparison methods. Five coders independently coded interviews, engaging in critical discussion to resolve disagreements. An audit trail, member checking, and peer debriefing enhanced credibility. Six umbrella themes and 20 sub-themes were identified. In this paper, the following six sub-themes are highlighted with direct implications for practice:1) compounding oppression, 2) being avoided or categorized due to others’ discomfort, 3) increased disrespect, 4) microaggressions, 5) acts of hate, and 6) cultural values/respect for elders as a protective factor. Implications include informing how practitioners may enhance support for older adults in preventing and coping with experiences of racialized ageism. Enhanced understanding of racialized ageism should also inform existing anti-ageism initiatives at the community level. Future research should focus on the experience of racialized ageist microaggressions and the relationship between racialized ageism and specific health outcomes.

A concentration-QTc analysis of vericiguat

Introduction

Vericiguat is a soluble guanylate cyclase stimulator developed for the treatment of symptomatic chronic heart failure (HF) in patients with ejection fraction less than 45% who had a previous decompensation event. A dedicated, randomised, Phase Ib, QT study of vericiguat (NCT03504982) in 74 adult patients with stable coronary artery disease demonstrated no clinically significant prolongation of the time-matched, placebo-adjusted change from baseline in the Fridericia-corrected QT interval (QTcF) after vericiguat 10 mg once daily at steady state.

Purpose

We conducted a concentration–QTc (C-QTc) modelling analysis, on data from the QT study, to investigate the potential effect of vericiguat on QTcF and define the vericiguat plasma concentration window within which a relevant prolongation in QTcF can be excluded.

Methods

In the QT study, the effect of vericiguat once daily (2.5 mg titrated to 5 mg and then to 10 mg [treatments A, B, C] over 42±9 days) on the QT interval was investigated. The positive control was a single dose of moxifloxacin 400 mg (treatment D) on Day 8 or Day 50 (7 days before the first vericiguat dose or 7 days after the last vericiguat dose), depending on the treatment sequence (Figure 1).

Baseline electrocardiogram assessments were performed 24 h before the start of treatment (“baseline”) and at follow-up (“back-up baseline”; Figure 1). Time-matched, baseline- and placebo-adjusted QTcF (ΔΔQTc) mean values and 90% confidence intervals (CIs) were calculated. Two analytical approaches were used to calculate ΔΔQTc. The first one (“single baseline ΔΔQTc” approach) was data-driven, where ΔΔQTc was adjusted with placebo- and either “baseline” or “back-up baseline”. The second one (“modelled baseline ΔΔQTc”) accounted for individual baseline and placebo effects, such as diurnal time course, used linear mixed effects and integrated all individual baseline and placebo data. Calculated ΔΔQTc values were then related to observed vericiguat concentrations in the C-QTc modelling step, performed with linear mixed effects implemented in R (R, the R Foundation for Statistical Computing, version 3.2.5).

Results

The C-QTc modelling of ΔΔQTc calculated with the “single baseline ΔΔQTc” approach indicated a positive, but non-significant, slope (Figure 2A). The “modelled baseline ΔΔQTc” approach indicated a positive and statistically significant slope (Figure 2B). In both cases, the upper limits of the 90% CI were below the threshold of clinical relevance of 10 ms within the investigated exposure range (up to 745 μg/l).

Conclusion

Based on the presented analysis, a clinically meaningful QT prolongation was robustly excluded within the plasma concentration range associated with the recommended target dose of vericiguat 10 mg. The C-QTc analysis supports the conclusion of the primary study statistical analysis that administration of vericiguat between 2.5 and 10 mg is not associated with a clinically meaningful QTc prolongation.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Funding was provided by Bayer AG, Berlin, Germany and Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA Figure 1Figure 2

Physiologically-based pharmacokinetic (PBPK) exploration of extrinsic factors influencing vericiguat pharmacokinetics

Introduction

Vericiguat is a once daily, novel oral stimulator of soluble guanylate cyclase (sGC) that showed clinical benefit in the Phase III VICTORIA study in heart failure patients with reduced ejection fraction (HFrEF, NCT02861534). Nonclinical and clinical studies demonstrated that the primary route of elimination of vericiguat was glucuronidation to an inactive metabolite M-1 (N-glucuronide). This glucuronidation was catalyzed by uridine 5'-diphospho-glucuronosyltransferases (UGT)1A9 as well as UGT1A1, thus vericiguat may have a potential for victim drug-drug interaction (DDI) when co-administered with potent UGT inhibitors.

Purpose

In a clinical DDI study with mefenamic acid as an UGT1A9 inhibitor no clinically relevant increase in vericiguat exposure in healthy subjects was observed (EudraCT 2014–000764–17). This analysis aims to prospectively investigate as extrinsic factors the DDI potential with atazanavir as a selective UGT1A1 inhibitor via full dynamic physiologically-based pharmacokinetic (PBPK) modelling.

Methods

A PBPK model for vericiguat and M-1 in healthy adults was built with PK-Sim (PBPK platform as part of the Open Systems Pharmacology Suite) by integrating physicochemical, in vitro metabolism and transporter data as well as PK data from clinical pharmacology studies in order to assess the victim DDI potential of vericiguat when co-administered with UGT inhibitors. First, PBPK models for mefenamic acid and atazanavir were separately developed and verified using published literature data. The PBPK model for vericiguat was then verified with regard to its fraction of metabolism by UGTs by comparing simulated and observed data of the clinical mefenamic acid DDI study. Finally, the UGT1A1 DDI potential of vericiguat was prospectively predicted by simulating an in silico study between the UGT1A1 inhibitor atazanavir and vericiguat.

Results

In line with the results of the clinical DDI study with mefenamic acid, an increase in total vericiguat exposure by 14% (area under the concentration time curve ratio (AUCR) of 1.14 (geoCV 5.3%; 90% population interval: 1.06 to 1.25) and peak exposure increase by 6% (CmaxR of 1.06; geoCV 5.9%; 90% population interval: 1.01 to 1.20) was simulated using the PBPK model. A prospective prediction of a virtual DDI trial between the UGT1A1 inhibitor atazanavir yielded an AUCR of 1.12 (geoCV 2.9%; 90% population interval: 1.07 to 1.17) and a CmaxR of 1.04 (geoCV 1.1%; 90% population interval: 1.03 to 1.06). The proposed population intervals for AUCR and CmaxR for both DDI studies lie within the default no-effect boundary of 0.80 to 1.25 according to the to January 2020 FDA DDI guideline.

Conclusion(s)

Results of UGT1A9-DDI simulations were consistent with those of the clinical study-The prospective UGT1A1-DDI simulation results suggest a low potential for vericiguat to be subject to DDI when co-administered with UGT1A1 inhibitors.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Funding for this research was provided by Bayer and Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA

Vericiguat clinical pharmacology programme: biopharmaceutical properties and potential intrinsic and extrinsic factor effects

Introduction

The Phase III VICTORIA study (NCT02861534), which evaluated vericiguat vs placebo in patients with worsening chronic heart failure (WCHF) with ejection fraction &lt;45%, demonstrated a significant reduction in the primary composite endpoint of cardiovascular death and HF hospitalisation.

Purpose

A comprehensive clinical pharmacological programme of 28 Phase I trials in &gt;650 participants was performed to inform use of vericiguat.

Methods

Biopharmaceutical properties, pharmacokinetics (PK) and the potential for intrinsic factors to influence vericiguat dose administration were investigated. The PK and pharmacodynamic (PD) interaction potential of vericiguat with other drugs was assessed.

Results

Vericiguat had a mean half-life of approximately 24 h and high bioavailability when taken with food, leading to the recommendation of once daily dosing with food. Due to the multi-pathway metabolism and excretion profile of vericiguat, there was a low risk of PK drug–drug interactions (DDI; Table). No clinically relevant PD DDI were identified between vericiguat and aspirin, warfarin, sacubitril/valsartan or nitrates. There was a relatively minor influence of intrinsic factors on vericiguat PK.

Conclusion

This clinical pharmacology programme supports use of vericiguat in patients with WCHF who are characterised by multiple comorbidities and polypharmacy.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Funding for this research was provided by Bayer AG, Berlin, Germany and Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA

Multiscale Modeling of Thiol Overoxidation in Peroxiredoxins by Hydrogen Peroxide

In this work, we employ a multiscale quantum-classical mechanics (QM/MM) scheme to investigate the chemical reactivity of sulfenic acids toward hydrogen peroxide, both in aqueous solution and in the protein environment of the peroxiredoxin alkyl hydroperoxide reductase E from Mycobacterium tuberculosis (MtAhpE). The reaction of oxidation of cysteine with hydrogen peroxides, catalyzed by peroxiredoxins, is usually accelerated several orders of magnitude in comparison with the analogous reaction in solution. The resulting cysteine sulfenic acid is then reduced in other steps of the catalytic cycle, recovering the original thiol. However, under some conditions, the sulfenic acid can react with another equivalent of oxidant to form a sulfinic acid. This process is called overoxidation and has been associated with redox signaling. Herein, we employed a multiscale scheme based on density function theory calculations coupled to the classical AMBER force field, developed in our group, to establish the molecular basis of thiol overoxidation by hydrogen peroxide. Our results suggest that residues that play key catalytic roles in the oxidation of MtAhpE are not relevant in the overoxidation process. Indeed, the calculations propose that the process is unfavored by this particular enzyme microenvironment.

Sarna sarcóptica en cerdos criados en cama profunda. Reporte de caso clínico

La sarna sarcóptica en los cerdos es causada por Sarcoptes scabiei var. suis el cual se distribuye ampliamente en los cinco continentes. Los productores porcícolas en general están preocupados por las infecciones parasitarias internas e ignoran las infestaciones parasitarias externas; estas últimas, causadas por S. scabiei tienen gran importancia económica ya que causa morbilidad, mortalidad, disminución de la fertilidad y de la tasa de conversión alimenticia. Este trabajo permitió determinar la presencia de sarna sarcóptica en cerdos criados bajo sistema de producción con cama profunda de una granja en el estado Guárico (Venezuela), utilizando las técnicas parasitológicas directas de flotación-concentración y microscopía directa. Los resultados demostraron que dos de siete muestras evaluadas fueron positivas con S. scabiei var. suis. El 100% de los animales presentaron lesiones de piel compatibles con la presencia del ácaro, pero el mismo solo pudo ser detectado en el 28,6% de ellos. La técnica de flotación-concentración fue más efectiva que la de microscopía directa. En este estudio describimos la primera detección de S. scabiei var. suis en cerdos domésticos en Venezuela criados en cama profunda.

Contribution of Implanted, Genetically Modified Muscle Progenitor Cells Expressing BMP-2 to New Bone Formation in a Rat Osseous Defect

Because muscle contains osteoprogenitor cells and has a propensity to form bone, we have explored its utility in healing large osseous defects. Healing is achieved by the insertion of muscle fragments transduced with adenovirus encoding BMP-2 (Ad.BMP-2). However, it is not known whether the genetically modified muscle contributes osteoprogenitor cells to healing defects or merely serves as a local source of BMP-2. This question is part of the larger debate on the fate of progenitor cells introduced into sites of tissue damage to promote regeneration. To address this issue, we harvested fragments of muscle from rats constitutively expressing GFP, transduced them with Ad.BMP-2, and implanted them into femoral defects in wild-type rats under various conditions. GFP⁺ cells persisted within defects for the entire 8 weeks of the experiments. In the absence of bone formation, these cells presented as fibroblasts. When bone was formed, GFP⁺ cells were present as osteoblasts and osteocytes and also among the lining cells of new blood vessels. The genetically modified muscle thus contributed progenitor cells as well as BMP-2 to the healing defect, a property of great significance in light of the extensive damage to soft tissue and consequent loss of endogenous progenitors in problematic fractures.

Aroma profile of malbec red wines from La Mancha region: Chemical and sensory characterization

The aroma of La Mancha Malbec red wines over four consecutive vintages was characterized by chemical and sensory analysis. Solid phase extraction (SPE) and gas chromatography-mass spectrometry (GC-MS) were used to isolate and analyze free volatile compounds. Quantitative Descriptive Sensory Analysis (QDA) was carried out to characterize the sensory aroma profile. A total of 79 free volatile compounds were identified and quantified in the wines over these four vintages. Volatile aroma compounds were classified into seven aromatic series and their odour activity values were calculated in order to determine the aroma impact compounds in these wines. The aroma sensory profile of these wines was characterized by red fruit, fresh, prune, liquorice, clove, caramel, leather, tobacco and coffee aromas. This study provides a complete aroma characterization of La Mancha Malbec red wines and it is proposed that these wines can be considered as an alternative to wines from traditional grape varieties of this region.

Irreversible electroporation of the liver: is there a safe limit to the ablation volume?

Irreversible electroporation is a fast-growing liver ablation technique. Although safety has been well documented in small ablations, our aim is to assess its safety and feasibility when a large portion of liver is ablated. Eighty-seven mice were subjected to high voltage pulses directly delivered across parallel plate electrodes comprising around 40% of mouse liver. One group consisted in 55 athymic-nude, in which a tumor from the KM12C cell line was grown and the other thirty-two C57-Bl6 non-tumoral mice. Both groups were subsequently divided into subsets according to the delivered field strength (1000 V/cm, 2000 V/cm) and whether or not they received anti-hyperkalemia therapy. Early mortality (less than 24 hours post-IRE) in the 2000 V/cm group was observed and revealed considerably higher mean potassium levels. In contrast, the animals subjected to a 2000 V/cm field treated with the anti-hyperkalemia therapy had higher survival rates (OR = 0.1, 95%CI = 0.02–0.32, p < 0.001). Early mortality also depended on the electric field magnitude of the IRE protocol, as mice given 1000 V/cm survived longer than those given 2000 V/cm (OR = 4.7, 95%CI = 1.8–11.8, p = 0.001). Our findings suggest that ionic disturbances, mainly due to potassium alterations, should be warned and envisioned when large volume ablations are performed by IRE.

Theoretical and experimental study on RF tumor ablation with internally cooled electrodes: when does the roll-off occur?

The Cool-tip is one of the most widely employed electrodes in radiofrequency (RF) ablation (RFA) of hepatic tumors. This electrode creates reliable geometry and coagulation zones. Despite the advantages of this electrode, during the ablation is produced a phenomenon called roll-off in which impedance increases, energy deposition completely stops and the lesion size cannot be increased. Consequently, the thermal lesion size is smaller and the tumors which can be ablated are smaller too. In this research we studied theoretical and experimentally the electrical-thermal performance of the Cool-tip electrode during RFA of hepatic tissue. Mainly, we were interested in the occurrence of the roll-off and its relationship with the tissue temperatures around the electrode. The theoretical model included the vaporization of the tissue and the variation of the thermal and electrical conductivities with temperature. The model was solved numerically using COMSOL Multiphysics software. For the experimental part we conducted a study in ex vivo liver tissue. The experimental and theoretical results showed that the roll-off is totally related when temperatures around 100 °C surrounds the tissue close to the center of the Cool-tip. The knowledge of this fact brings a powerful tool to analyze alternative methods or techniques to avoid the roll-off.

A Controlled Randomized Study on the Efficacy of Short-Term Dinamic Psychotherapy in Borderline Personality Disorders (BPD). Preliminary Results

Introduction

Four psychotherapies have been recognized as effective with scientific evidence for the treatment of BPD, but are long term techniques. It is necessary to explore new time limited psychotherapies in order to be more accessible.

We have developed a specific manualized psychotherapy for BPD named Psychic Representation focused Psychotherapy (PRFP)

Objectives

To assess the efficacy of the PRFP in BPD in an outpatient care setting compared to a control group receiving psychiatric treatment “as usual” in several specific symptoms and in diminishing the disability due to the illness.

Methods

60 subjects with BPD were randomized to one of the two treatment groups. The study group has received PRFP with 20 sessions on a weekly basis; the control group has received treatment “as usual”. Both groups may receive psychopharmacological treatment. The assessment is done in four time-points: at baseline, after the psychotherapy or conventional treatment (six months), and at a six and twelve month's follow-up period.

Results

Preliminary results of the first 30 patients (control group 17, experimental group 13, without significant differences, Age 18–35 years; 70% women) assessed at the baseline and at the end of the intervention (six months). Experimental group reached a statistically significant clinical improvement over the controls in all measured variables: Scales: SCL-90; Zanarini ; MDRS; Barrat; STAI anxiety state; Rosemberg self-esteem and SASS social adaptation.

Conclusion

The preliminary results are encouraging and reveal that this method could be effective. This study state the interest in develop more studies about time limited psychotherapy for BPD.

Experimental and theoretical study of an internally cooled bipolar electrode for RF coagulation of biological tissues

Although some types of bipolar electrodes have been broadly employed in clinical practice to coagulate biological tissue by means of radiofrequency (RF) currents, there is still scanty available information about their electrical-thermal behaviour. We are focused on internally cooled bipolar electrodes. The goal of our study was to know more about the behavior of this kind of electrodes. For that, we planned an experimental and theoretical model. The experimental study was based on bovine hepatic ex vivo tissue and the theoretical model was based on the Finite Element Method (FEM). In order to check the feasibility of the theoretical model, we assessed both theoretically and experimentally the effect of the internal cooling characteristics of the bipolar electrode (flow rate and coolant temperature) on the impedance progress during RF heating and coagulation zone dimensions. The experimental and theoretical results were in good agreement, which suggests that the theoretical model could be useful to improve the design of cooled bipolar electrodes.

Serum lipid profiles and homocysteine levels in adults with stroke or myocardial infarction in the town of Gombe in northern Nigeria

While the incidence of infectious diseases has been on the decline in developing countries, the toll of cardiovascular diseases, including stroke and myocardial infarction, has been increasing. The impression of physicians in certain regions of the western Sahel, including the state of Gombe in northeastern Nigeria, is that macrovascular disease in the indigenous population is on the rise. This study was, therefore, undertaken to compare well-established risk factors for cardiovascular disease in a group of 53 men (n=34) and women (n=19) in the town of Gombe who had suffered a stroke or heart attack with the corresponding parameters in 48 age- and gender-matched healthy adults living in the same environment. The parameters of cardiovascular diseases considered were: overweight and obesity, blood pressure, lipid profiles, and homocysteine. While the male and female patients who had suffered stroke (n=48) or heart attack (n=5) were borderline hypertensive, their mean body mass index values were not different from the corresponding values of their control groups. Although the serum homocysteine levels of the patients and controls were not significantly different, 85% of the stroke patients had serum homocysteine levels greater than 10 microM. These high homocysteine levels could not be accounted for by sub-optimal folate or vitamin B 12 status. The serum levels of HDL-cholesterol and triglyceride were not significantly different between the male and female patients and their respective controls. However, the males, but not the females, with macrovascular disease had significantly higher levels of total cholesterol (161 vs 137 mg/dL, p=0.04) and LDL-cholesterol (91 vs 70 mg/dL, p=0.02). In addition, both female and male stroke/myocardial infarction patients exhibited an elevated LDL-cholesterol/HDL-cholesterol ratio. These results indicate that blood pressure and the LDL-cholesterol/HDL-cholesterol ratio are associated with stroke and myocardial infarction in adults in northern Nigeria, thereby creating potential opportunities for possible public-health interventions.

Factors influencing the anti-inflammatory effect of dexamethasone therapy in experimental pneumococcal meningitis

Dexamethasone (DXM) interferes with the production of tumour necrosis factor-alpha (TNF-alpha) and interleukin-1 (IL-1) and can thereby diminish the secondary inflammatory response that follows initiation of antibacterial therapy. A beneficial effect on the outcome of Haemophilus meningitis in children has been proven, but until recently the effect of DXM therapy in pneumococcal meningitis was uncertain. The aim of the present study was to evaluate factors that might influence the modulatory effect of DXM on the antibiotic-induced inflammatory response in a rabbit model of pneumococcal meningitis. DXM (1 mg/kg) was given intravenously 30 min before or 1 h after administration of a pneumococcal cell wall extract, or the first dose of ampicillin. In meningitis induced by cell wall extract, DXM therapy prevented the increase in cerebrospinal fluid (CSF) leucocyte and lactate concentrations, but only if given 30 min before the cell wall extract. In meningitis caused by live organisms, initiation of ampicillin therapy resulted in an increase in CSF TNF-alpha and lactate concentrations only in animals with initial CSF bacterial concentrations > or =5.6 log10 cfu/mL. In those animals, DXM therapy prevented significant elevations in CSF TNF-alpha [median change -184 pg/mL, -114 pg/mL versus +683 pg/mL with DXM (30 min before or 1 h after ampicillin) versus controls (no DXM), respectively, P=0.02] and lactate concentrations [median change -10.6 mmol/L, -1.5 mmol/L versus +14.3 mmol/L with DXM (30 min before or 1 h after ampicillin) versus controls (no DXM), respectively, P=0.01]. These effects were independent of the timing of DXM administration. In this model of experimental pneumococcal meningitis, an antibiotic-induced secondary inflammatory response in the CSF was demonstrated only in animals with high initial CSF bacterial concentrations (> or =5.6 log10 cfu/mL). These effects were modulated by DXM therapy whether it was given 30 min before or 1 h after the first dose of ampicillin.

Congenital dyserthropoietic anaemia other than type I to III with a peculiar erythroblastic morphology

Here, we report the case of a child who, since birth, showed persistent macrocytosis and elevated mean corpuscular volume of the erythrocytes. Bone marrow biopsy revealed gross disorganisation of the erythroblastic series both at the light and electron microscopic examination, with complete absence of dysplastic features in the granulocytic and megakaryocytic series. Common causes of macrocytosis were excluded. The spectrum of morphological findings were not consistent with any of the classical types of congenital dyserythropoietic anaemias (CDAs) and serological findings of CDA type II were absent. The most outstanding feature was a marked irregularity of the nuclear outline of the late erythroblasts that presented thick-ending finger-like projections. The combination of macrocytosis without anaemia and these morphologic erythroblastic changes have not been previously reported in the setting of classical and variant forms of CDAs.

Differential expression of putative cell death regulator genes in near-isogenic, resistant and susceptible barley lines during interaction with the powdery mildew fungus

We analysed pathogenesis-related expression of genes, that are assumed to be involved in ubiquitous plant defence mechanisms like the oxidative burst, the hypersensitive cell death reaction (HR) and formation of localized cell wall appositions (papillae). We carried out comparative northern blot and RT-PCR studies with near-isogenic barley (Hordeum vulgareL. cv. Pallas) lines (NILs) resistant or susceptible to the powdery mildew fungus race A6 (Blumeria graminis f.sp. hordei, BghA6). The NILs carrying one of the R-genes Mla12, Mlg or the mlo mutant allele mlo5 arrest fungal development by cell wall appositions (mlo5) or a HR (Mla12) or both (Mlg). Expression of an aspartate protease gene, an ascorbate peroxidase gene and a newly identified cysteine protease gene was up-regulated after inoculation with BghA6, whereas the constitutive expression-level of a BAS gene, that encodes an alkyl hydroperoxide reductase, was reduced. Expression of a newly identified barley homologue of a mammalian cell death regulator, Bax inhibitor 1, was enhanced after powdery mildew inoculation. An oxalate oxidase-like protein was stronger expressed in NILS expressing penetration resistance. A so far unknown gene that putatively encodes the large subunit of a superoxide generating NADPH oxidases was constitutively expressed in barley leaves and its expression pattern did not change after inoculation. A newly identified barley Rac1 homologue was expressed constitutively, such as the functionally linked NADPH oxidase gene. Gene expression patterns are discussed with regard to defence mechanisms and signal transduction.

ATP synthase is necessary for microcin H47 antibiotic action

Microcin H47 is a gene-encoded peptide antibiotic produced by a natural Escherichia coli strain isolated in Uruguay. In order to identify cellular components necessary for its antibiotic action, microcin H47-resistant mutants isolated in this work, as well as previously described mutants affected in membrane proteins, were analyzed. These studies indicated that (i) receptor outer membrane proteins for ferric-catechol siderophores would be involved in microcin-specific binding to the cell surface, (ii) the TonB pathway is needed for microcin H47 uptake, and (iii) the presence of the ATP synthase complex is necessary for microcin action. The possibility that this last structure contains the antibiotic target is discussed.

Synthesis, isolation and characterization of Plasmodium falciparum antigenic tetrabranched peptide dendrimers obtained by thiazolidine linkages

Different chemical alternatives were evaluated for obtaining immunogenic polypeptidic macromolecules which could then be used as vaccines. These were based on the ligation reaction between an unprotected immunogenic peptide and an unprotected multifunctional core peptide; polyantigens, designated dendrimers because their form resembles that of dendritic cells, were thus obtained. The antigen-core ligation alternatives, studied by indirect synthesis, were the formation of oxime, hydrazone and thiazolidine linkages, making use of the reaction between a weak base (acting as nucleophile) and an alkyl aldehyde. The other alternative was the formation of a thioether linkage between a sulfydryl and an alkyl halide. Finally, a multiple antigen peptide (MAP) was synthesized by direct synthesis. All reactions were monitored by SEC-HPLC and SDS-PAGE. Dendrimer molecular mass obtained was confirmed by MS MALDI-TOF. Dendrimer purification was first carried out by concentrating crude reaction products with CP-5000 centricons and (using SEC-HPLC) pure tetramers were then obtained. A 20-residue 9376 immunogenic sequence, from Plasmodium falciparum apical merozoite antigen protein (AMA-1), was used to study the best alternative for chemical ligation. It was observed that thiazolidine formation proceeded with greater yield and in less time than the others. A tetramer has been simultaneously synthesized via thiazolidine with the SPf-66 antimalarial vaccine 45-residue monomer, proving the technique's versatility. The 9376 peptide disulfide bound polymer and SPf-66 (as well as their tetrameric thiazolidine dendrimers) were inoculated in rabbits to evaluate their antibody response. It was observed that titers for tetrameric thiazolidine dendrimers were not just greater but were also sustained over time. Western blot for pre-immune and immune sera showed that dendrimer sera recognized specific Plasmodium falciparum proteins as well as disulfide-bound polymers.

Step-by-step uncoordination of the pyrazolyl rings of hydrotris(pyrazolyl)borate ligands in comlexes of Rh and RhIII

Compounds of rhodium(I) and rhodium(III) that contain ancillary hydrotris(pyrazolyl)borate ligands (Tp') react with monodentate and bidentate tertiary phosphanes in a step-wise manner, with incorporation of P-donor atoms and concomitant replacement of the Tp' pyrazolyl rings. Accordingly, [Rh(kappa3-TpMe2)(C2H4)(PMe3)] (1b), converts initially into [Rh(kappa2-TpMe2)-(PMe3)2] (3), and then into [Rh(kappa1-TpMe2)-(PMe3)3] (2) upon interaction with PMe3 at room temperature, in a process which can be readily reversed under appropriate experimental conditions. Full disengagement of the Tp' ligand is feasible to give Tp' salts of rhodium(I) complex cations, for example, [Rh(CO)(dppp)2]-[TpMe2,4-Cl] (5; dppp = Ph2P(CH2)3PPh2), or [Rh(dppp)2][TpMe2,4-Cl] (6). Bis(hydride) derivatives of rhodium(III) exhibit similar substitution chemistry, for instance, the neutral complex [Rh(Tp)-(H)2(PMe3)] reacts at 20 degrees C with an excess of PMe3 to give [Rh(H)2-(PMe3)4][Tp] (9b). Single-crystal X-ray studies of 9b, conducted at 143 K, demonstrate the absence of bonding interactions between the [Rh(H)2(PMe3)4]+ and Tp ions, the closest Rh...N contact being at 4.627 A.

Culture and the organization of psychiatric care

Health care systems of the 21st century confront the confluence of two important forces that conform their policies regarding culture. On the one hand, population demographics announce increasing diversity; on the other, a rising knowledge base regarding the impact of culture on mental health awaits to be incorporated into actual clinical practices nationwide. As regulators and payors incorporate this knowledge into their practices, standards and guidelines, the dream of mental health cultural parity will come somewhat closer to fulfillment. In this article, we have aimed to review how the integration of developing knowledge and evolving standards may contribute to such fulfillment.

Haloperidol blood levels in acute mania with psychosis

In this study, the authors examined the relationship between steady-state haloperidol blood levels and clinical response in patients with acute psychotic mania. Fifty-four inpatients with acute mania were randomly assigned to receive either haloperidol 25 mg/day or haloperidol 5 mg/day. Each subject also received a concomitant medication: lorazepam 4 mg/day, lithium, or placebo. The relationship between steady-state haloperidol blood levels and clinical improvement was studied using analysis of covariance. There was wide interindividual variation in the haloperidol blood level-dose ratio. Haloperidol blood levels (log-transformed) were found to significantly correlate with clinical response in acute mania. Low-dose haloperidol with concomitant lithium may produce an optimal response in acute mania. Haloperidol blood levels may be clinically useful in identifying patients who are nonresponsive because of low drug levels and, hence, in enhancing optimal haloperidol dosing for acute mania with psychosis.

Identification of novel RP2 mutations in a subset of X-linked retinitis pigmentosa families and prediction of new domains

X-linked Retinitis Pigmentosa (XLRP) shows a huge genetic heterogeneity with almost five distinct loci on the X chromosome. So far, only two XLRP genes have been identified, RPGR (or RP3) and RP2, being mutated in approximately 70% and 10% of the XLRP patients. Clinically there is no clearly significative difference between RP3 and RP2 phenotypes. In the attempt to assess the degree of involvement of the RP2 gene, we performed a complete mutation analysis in a cohort of patients and we identified five novel mutations in five different XLRP families. These mutations include three missense mutations, a splice site mutation, and a single base insertion, which, because of frameshift, anticipates a stop codon. Four mutations fall in RP2 exon 2 and one in exon 3. Evidence that such mutations are different from the 21 RP2 mutations described thus far suggests that a high mutation rate occurs at the RP2 locus, and that most mutations arise independently, without a founder effect. Our mutation analysis confirms the percentage of RP2 mutations detected so far in populations of different ethnic origin. In addition to novel mutations, we report here that a deeper sequence analysis of the RP2 product predicts, in addition to cofactor C homology domain, further putative functional domains, and that some novel mutations identify RP2 amino acid residues which are evolutionary conserved, hence possibly crucial to the RP2 function.

Determination of phenols, flavones, and lignans in virgin olive oils by solid-phase extraction and high-performance liquid chromatography with diode array ultraviolet detection

A simple analytical method for the quantitative determination of phenols, flavones, and lignans in virgin olive oils was developed. The polar fraction was isolated from small amounts of oil sample (2.5 g) by solid-phase extraction (SPE) using diol-phase cartridges, and the extract was analyzed by reversed-phase HPLC coupled with diode array UV detection. Chromatographic separation of pinoresinol, cinnamic acid, and 1-acetoxypinoresinol was achieved. Repeatability (RSD < 6.5%), recovery (> 90%), and response factors for each identified component were determined. SPE on amino-phase cartridges was used for isolating acidic phenols and as an aid for phenol identification. For the first time, 2-(4-hydroxyphenyl)ethyl acetate was detected in olive oils. The aldehydic structure of the ligstroside aglycon was confirmed by NMR spectroscopy. The colorimetric determination of total o-diphenolic compounds by reaction with molybdate was consistent with their HPLC determination. Differences between results obtained by liquid-liquid extraction and SPE were not statistically significant.

Hormonal regulation of the contractile response induced by okadaic acid in the rat uterus

The contractile effect of okadaic acid (OA), a highly selective inhibitor of protein serine/threonine phosphatases, was analyzed in the rat uterus during the estrous cycle and during the course of pregnancy. Contractile effects were related to circulating levels of estrogen and progesterone and to mRNA levels of myosin light chain kinase (MLCK) and of myosin light chain protein phosphatase catalytic (PP1-delta) and larger regulatory subunit (MYPT). Both in nonpregnant and pregnant uteri, OA (20 microM) induced a transient contraction, which after plateauing, slowly decreased. In the nonpregnant uterus, the amplitude of this contraction varied at different stages of the estrous cycle, being higher at proestrus and lower at diestrus. In the pregnant uterus, the contraction to OA increased significantly during the course of pregnancy, reaching a maximum in day 21 pregnant rats, and declined after delivery. Whatever the day of pregnancy, the amplitude of the contraction to OA was not significantly modified when obtained in Ca(2+)-free solution. The magnitude of the OA-induced contraction in spontaneously cycling and pregnant rats was positively correlated to the ratio of estrogen/progesterone serum levels. Reverse transcription-polymerase chain reaction assays on myometrial tissue demonstrated that mRNA expression of PP1-delta and MYPT was higher at early (day 3) than at late (day 21) pregnancy. MLCK mRNA levels were similar in day 3 and day 21 pregnant rats. These data suggest that changes in the expression and activity of myosin phosphatase may contribute to modulating the level of uterine contractile force during the estrous cycle, pregnancy, and labor.

Barley Mla and Rar mutants compromised in the hypersensitive cell death response against Blumeria graminis f.sp. hordei are modified in their ability to accumulate reactive oxygen intermediates at sites of fungal invasion

The pathogenesis-related accumulation of superoxide radical anions (O2*-) and hydrogen peroxide (H2O2) was comparatively analyzed in a barley line (Hordeum vulgare L. cv Sultan-5) carrying the powdery mildew (Blumeria graminis f.sp. hordei, Speer, Bgh) resistance gene Mla12, and in susceptible mutants defective in Mla12 or in genes "required for Mla12-specified disease resistance" (Rar1 and Rar2). In-situ localization of reactive oxygen intermediates was performed both by microscopic detection of azide-insensitive nitroblue tetrazolium (NBT) reduction or diaminobenzidine (DAB) polymerization, and by an NBT-DAB double-staining procedure. The Mla12-mediated hypersensitive cell death occurred either in attacked epidermal cells or adjacent mesophyll cells of wild-type plants. Whole-cell H2O2 accumulation was detected in dying cells, while O2*- emerged in adjacent cells. Importantly, all susceptible mutants lacked these reactions. An oxalate oxidase, which is known to generate H2O2 and has been implicated in barley resistance against the powdery mildew fungus, was not differentially expressed between the wild type and all mutants. The results demonstrate that the Rar1 and Rar2 gene products, which are control elements of R-gene-mediated programmed cell death, also control accumulation of reactive oxygen intermediates but not the pathogenesis-related expression of oxalate oxidase.

Mutations in Ror1 and Ror2 genes cause modification of hydrogen peroxide accumulation in mlo-barley under attack from the powdery mildew fungus

Abstract Race nonspecific resistance of barley against the barley powdery mildew fungus (Blumeria Graminis f.sp. Hordei, Speer, Bgh) is mediated by recessive mlo alleles and is controlled by at least two additional genes 'required for ml o-specified disease resistance' (Ror1 and Ror2). The pathogenesis-related accumulation of hydrogen peroxide (H(2)O(2)) was comparatively analysed in a susceptible barley line (Hordeum vulgare L. Cv Ingrid, genotype Mlo Ror1, Ror2), a resistant Ingrid backcross line carrying the mutant allele mlo5 (BCIngrid-mlo5, genotype mlo5 Ror1 Ror2), and in the moderately susceptible mutants A44 and A89 (genotypes mlo5 Ror1 ror2 and mlo5 ror1-2 Ror2, respectively). In situ localization of H(2)O(2) was performed by microscopic detection of 3,3-diaminobenzidine (DAB) polymerization. In BCIngrid-mlo5, penetration resistance against Bgh attack was closely correlated to H(2)O(2) accumulation in cytoplasmic aggregates and cell wall appositions beneath the appressorium. In contrast, H(2)O(2) accumulation was almost completely absent in susceptible Ingrid. Lines with mutations in Ror genes showed less H(2)O(2) accumulation beneath appressoria, but more interaction sites with whole cell H(2)O(2) accumulation and hypersensitive cell death response than resistant BCIngrid-mlo5. Thus, mutations in Ror1 or Ror2 genes influence the cellular pattern of H(2)O(2) accumulation in mlo plants attacked by Bgh. The data support the hypothesis that H(2)O(2) accumulation is involved in resistance to fungal penetration.

Treatment of catheter-induced thrombotic superior vena cava syndrome: a single institution's experience

Thrombosis is the most frequent benign etiology of superior vena cava syndrome among cancer patients who have a long-term central venous catheter. In this paper, six cases of thrombotic superior vena cava syndrome are discussed. There were four women and two men. One patient was treated with streptokinase and five with urokinase. The mean age was 46 years (range 22-69), and the mean time for thrombosis development after catheter insertion was 125 days (range: 53-211 days). The mean time for resolution of thrombosis was 7 days (range 2-11) in five patients. One patient had no response to fibrinolysis.

Amino terminal peptides of the ring infected erythrocyte surface antigen of Plasmodium falciparum bind specifically to erythrocytes

The Ring-Infected Erythrocyte Surface Antigen (Pf155/RESA) sequence was chemically synthesized in fifty four 20-mer sequential peptides, covering the entire protein, each of which was tested in erythrocyte binding assays. Peptides 6671 and 6673, corresponding to residues 141-160 and 181-200, respectively, presented a high specific binding activity to erythrocytes with affinity constants of 190 nM and 105 nM respectively. Their binding was sensitive to previous enzymatic treatment of erythrocytes. A region of peptide 6673 has been identified, very recently, as a B-cell epitope, target of neutralizing antibodies (Siddique AB, Iqbal J, Ahlborg N, Wâhlin FB, Perlmann P, Berzins K. Antibodies to nonrepeat sequences of antigen Pf155/RESA of Plasmodium falciparum inhibit parasite growth in vitro. Parasitol Res 1998;84:485-91). The critical residues for erythrocyte binding for peptide 6671 (MTDVNRYRYSNNYEAIPHIS) and for peptide 6673 (LGRSGGDIIKKMQTLWDEIM) were recognized. Based on these data, the presence of five functional regions of RESA is postulated.