An EMG-Based Objective Function for Human-in-the-Loop Optimization.

Advancements in wearable robots aim to improve the users' motion, performance, and comfort by optimizing, mainly, energetic cost (EC). However, EC is a noisy measurement with a physiological delayed response that requires long evaluation periods and wearing an uncomfortable mask. This study aims to estimate and minimize an EMG-based objective function that describes the natural energetic expenditure of individuals walking. This objective is assessed by combining multiple electromyography (EMG) variables from the EMG intensity and muscle synergies. To evaluate this objective function simply and repeatedly, we prescribed step frequency (SF) via a metronome and optimized this frequency to minimize muscle activity demands. Further, a linear mixed-effects model was fitted for EC, with the EMG variables as fixed-effects and a random intercept that varies by participant. After the model was fitted to the data, a cubic polynomial was used to identify the optimal SF that reduces the overall EMG-based objective function. Our analysis outlines that the proposed objective function is comparable to the EC during walking, the primary objective function used in human-in-the-loop optimization. Thus, this EMG-based objective function could be potentially used to optimize wearable robots and improve human-robot interaction.

Factors associated with suicidal intent in economically active patients diagnosed with major depression.

INTRODUCTION: Every 40s, one person in the world commits suicide. As such, suicide is considered a public health problem, and prior suicide attempt is one of the risk factors associated with completed suicide. Despite the strategies implemented and the studies carried out, in Colombia suicide figures are on the rise, more markedly in the economically active population. OBJECTIVE: To identify the sociodemographic, family, personal, economic and religious factors associated with suicide attempt in patients of productive age (18-62 years old) in a mental health institution in Bogota, Colombia. METHODS: An analytical prevalence study was conducted at the Nuestra Señora de la Paz mental health clinic in Bogota. To explore the relationship between the factors described and suicide attempt, a review of 350 medical records of the selected population was carried out. RESULTS: In total, 37.7% of the sample presented a suicide attempt. Associations were found between the suicide attempt and higher education than primary school (PR=0.47 [0.23-0.97]), no economic income (PR=1.72 [1.13-2.61]), no partner (PR=2.10 [1.33-3.32]), alcohol consumption (P=.045), hallucinogen use (PR=2.39 [0.97-3.43]) and the presence of personality disorder (PR=1.93 [1.11-3.34]). CONCLUSIONS: The results of the study are similar to those previously described in other studies around the world. There is a need to recognise and address various factors associated with suicide attempt in depressed patients in order to implement promotion and prevention actions, early identification and specific interventions that have an impact on the numbers of completed suicide in the country.

Factores asociados con intento suicida en pacientes económicamente activos con diagnóstico de depresión mayor

Introducción: En el mundo, cada 40 segundos una persona se quita la vida; el suicidio se considera un problema de salud pública, y el intento de suicidio previo es uno de los factores de riesgo relacionados con suicidio consumado. A pesar de las estrategias implementadas y los estudios realizados, en Colombia las cifras de suicidio van en ascenso, de manera más marcada en la población económicamente activa. Objetivo: Identificar los factores sociodemográficos, familiares, personales, económicos y religiosos asociados con el intento suicida en pacientes con trastorno depresivo en edad productiva (18-62 arios), en una institución de salud mental en Bogotá, Colombia. Métodos: Se realizó un estudio de prevalencia analítica en la Clínica de Nuestra Señora de la Paz, de Bogotá; para explorar la relación entre los factores descritos y el intento suicida, se realizó una revisión de 350 historias clínicas de la población seleccionada. Resultados: El 37,7% de la muestra presentó intento de suicidio. Se encontraron asociaciones entre el intento de suicidio y la formación superior a primaria (RP = 0,47 [0,23-0,97]), no recibir ingresos (RP = 1,72 [1,13-2,61]), no tener pareja (RP = 2,10 [1,33-3,32]), el consumo de alcohol (p = 0,045), el consumo de alucinógenos (RP = 2,39 [0,97-3,43]) y la presencia de trastorno de personalidad (RP = 1,93 [1,11-3,34]). Conclusiones: Los resultados del estudio son similares a los descritos previamente en el mundo. Es necesario reconocer y abordar diversos factores asociados con el intento de suicidio en pacientes depresivos para desplegar acciones de promoción y prevención, identificación temprana e intervenciones específicas que impacten en las cifras de suicidio consumado en el país.

Introduction: Every 40 seconds, one person in the world commits suicide. As such, suicide is considered a public health problem, and prior suicide attempt is one of the risk factors associated with completed suicide. Despite the strategies implemented and the studies carried out, in Colombia suicide figures are on the rise, more markedly in the economically active population. Objective: To identify the sociodemographic, family, personal, economic and religious factors associated with suicide attempt in patients of productive age (18-62 years old) in a mental health institution in Bogota, Colombia. Methods: An analytical prevalence study was conducted at the Nuestra Señora de la Paz mental health clinic in Bogota. To explore the relationship between the factors described and suicide attempt, a review of 350 medical records of the selected population was carried out. Results: In total, 37.7% of the sample presented a suicide attempt. Associations were found between the suicide attempt and higher education than primary school (PR = 0.47 [0.23-0.97]), no economic income (PR = 1.72 [1.13-2.61]), no partner (PR = 2.10 [1.33-3.32]), alcohol consumption (p = 0.045), hallucinogen use (PR = 2.39 [0.97-3.43]) and the presence of personality disorder (PR= 1.93 [1.11-3.34]). Conclusions: The results of the study are similar to those previously described in other studies around the world. There is a need to recognize and address various factors associated with suicide attempt in depressed patients in order to implement promotion and prevention actions, early identification and specific interventions that have an impact on the numbers of completed suicide in the country.

Human-in-the-Loop Optimization of Wearable Robotic Devices to Improve Human-Robot Interaction: A Systematic Review.

This article presents a systematic review on wearable robotic devices that use human-in-the-loop optimization (HILO) strategies to improve human-robot interaction. A total of 46 HILO studies were identified and divided into upper and lower limb robotic devices. The main aspects from HILO were identified, reviewed, and classified in four areas: 1) human-machine systems; 2) optimization methods; 3) control strategies; and 4) experimental protocols. A variety of objective functions (physiological, biomechanical, and subjective), optimization strategies, and optimized control parameters configurations used in different control strategies are presented and analyzed. An overview of experimental protocols is provided, including metrics, tasks, and conditions tested. Moreover, the relevance given to training or adaptation periods was explored. We outline an HILO framework that includes current wearable robots, optimization strategies, objective functions, control strategies, and experimental protocols. We conclude by highlighting current research gaps and defining future directions to improve the development of advanced HILO strategies in upper and lower limb wearable robots.

Therapeutic benefits of lower limb prostheses: a systematic review.

BACKGROUND: Enhancing the quality of life of people with a lower limb amputation is critical in prosthetic development and rehabilitation. Yet, no overview is available concerning the impact of passive, quasi-passive and active ankle-foot prostheses on quality of life. OBJECTIVE: To systematically review the therapeutic benefits of performing daily activities with passive, quasi-passive and active ankle-foot prostheses in people with a lower limb amputation. METHODS: We searched the Pubmed, Web of Science, Scopus and Pedro databases, and backward citations until November 3, 2021. Only English-written randomised controlled trials, cross-sectional, cross-over and cohort studies were included when the population comprised individuals with a unilateral transfemoral or transtibial amputation, wearing passive, quasi-passive or active ankle-foot prostheses. The intervention and outcome measures had to include any aspect of quality of life assessed while performing daily activities. We synthesised the participants' characteristics, type of prosthesis, intervention, outcome and main results, and conducted risk of bias assessment using the Cochrane risk of bias tool. This study is registered on PROSPERO, number CRD42021290189. RESULTS: We identified 4281 records and included 34 studies in total. Results indicate that quasi-passive and active prostheses are favoured over passive prostheses based on biomechanical, physiological, performance and subjective measures in the short-term. All studies had a moderate or high risk of bias. CONCLUSION: Compared to passive ankle-foot prostheses, quasi-passive and active prostheses significantly enhance the quality of life. Future research should investigate the long-term therapeutic benefits of prosthetics devices.

Characterizing fall risk factors in Belgian older adults through machine learning: a data-driven approach.

BACKGROUND: Falls are a major problem associated with ageing. Yet, fall-risk classification models identifying older adults at risk are lacking. Current screening tools show limited predictive validity to differentiate between a low- and high-risk of falling. OBJECTIVE: This study aims at identifying risk factors associated with higher risk of falling by means of a quality-of-life questionnaire incorporating biological, behavioural, environmental and socio-economic factors. These insights can aid the development of a fall-risk classification algorithm identifying community-dwelling older adults at risk of falling. METHODS: The questionnaire was developed by the Belgian Ageing Studies research group of the Vrije Universiteit Brussel and administered to 82,580 older adults for a detailed analysis of risk factors linked to the fall incidence data. Based on previously known risk factors, 139 questions were selected from the questionnaire to include in this study. Included questions were encoded, missing values were dropped, and multicollinearity was assessed. A random forest classifier that learns to predict falls was trained to investigate the importance of each individual feature. RESULTS: Twenty-four questions were included in the classification-model. Based on the output of the model all factors were associated with the risk of falling of which two were biological risk factors, eight behavioural, 11 socioeconomic and three environmental risk factors. Each of these variables contributed between 4.5 and 6.5% to explaining the risk of falling. CONCLUSION: The present study identified 24 fall risk factors using machine learning techniques to identify older adults at high risk of falling. Maintaining a mental, physical and socially active lifestyle, reducing vulnerability and feeling satisfied with the living situation contributes to reducing the risk of falling. Further research is warranted to establish an easy-to-use screening tool to be applied in daily practice.

Evaluation of an articulated passive ankle-foot prosthesis.

BACKGROUND: Current ankle prostheses for people with unilateral transtibial amputation (TTA) or transfemoral amputation (TFA) are unable to mimic able-bodied performance during daily activities. A new mechanical ankle-foot prosthesis was developed to further optimise the gait of people with a lower-limb amputation. This study aimed to evaluate the Talaris Demonstrator (TD) during daily activities by means of performance-related, physiological and subjective outcome measures. MATERIALS AND METHODS: Forty-two participants completed a protocol assessing performance and functional mobility with their current prosthesis and the TD. The protocol comprised the L-test, 2 min of stair climbing, 2 min of inclined treadmill walking, 6 min of treadmill walking at 3 different speeds in consecutive blocks of 2 min, and a 3-m Backward Walk test (3mBWT). Heart rate was measured during each task, and oxygen uptake was collected during all tasks except for the L-test and 3mBWT. Time of execution was recorded on the L-test and 3mBWT, and the rate of perceived exertion (score = 6-20), fatigue and comfort (score = 0-100) were assessed after each task. Paired sample t-tests and Wilcoxon Signed-rank tests were performed to compare outcomes between prosthetic devices. Benjamini-Hochberg corrections were applied to control for multiple comparisons with a level of significance set at α = 0.05. RESULTS: Subjects with a TTA (N = 28) were faster with their current prosthesis compared to the TD on the L-test and 3mBWT (p = 0.005). In participants with a TFA (N = 14), we observed a tendency towards a higher heart rate during the L-test and towards increased comfort during inclined walking, with the TD compared to the participants' current prosthetic device (0.05 < p < 0.10). Further, no significant results were observed. CONCLUSION: The Talaris Demonstrator is a novel state-of-the-art passive ankle-foot prosthesis for both people with a TTA and TFA. Subjective measures indicate the added value of this device, while overall task performance and intensity of effort do not differ between the Talaris Demonstrator and the current prosthesis. Further investigations unravelling both acute and more prolonged adaptations will be conducted to evaluate the TD more thoroughly.

Factors Associated with Suicidal Intent in Economically Active Patients Diagnosed with Major Depression. / Factores asociados con intento suicida en pacientes económicamente activos con diagnóstico de depresión mayor.

INTRODUCTION: Every 40seconds, one person in the world commits suicide. As such, suicide is considered a public health problem, and prior suicide attempt is one of the risk factors associated with completed suicide. Despite the strategies implemented and the studies carried out, in Colombia suicide figures are on the rise, more markedly in the economically active population. OBJECTIVE: To identify the sociodemographic, family, personal, economic and religious factors associated with suicide attempt in patients of productive age (18-62 years old) in a mental health institution in Bogota, Colombia. METHODS: An analytical prevalence study was conducted at the Nuestra Señora de la Paz mental health clinic in Bogota. To explore the relationship between the factors described and suicide attempt, a review of 350 medical records of the selected population was carried out. RESULTS: In total, 37.7% of the sample presented a suicide attempt. Associations were found between the suicide attempt and higher education than primary school (PR=0.47 [0.23-0.97]), no economic income (PR=1.72 [1.13-2.61]), no partner (PR=2.10 [1.33-3.32]), alcohol consumption (p=0.045), hallucinogen use (PR=2.39 [0.97-3.43]) and the presence of personality disorder (PR=1.93 [1.11-3.34]). CONCLUSIONS: The results of the study are similar to those previously described in other studies around the world. There is a need to recognise and address various factors associated with suicide attempt in depressed patients in order to implement promotion and prevention actions, early identification and specific interventions that have an impact on the numbers of completed suicide in the country.

Venezuela: la joya de la corona entre la pandemia y la amenaza de guerra / Venezuela: the jewel in the crown between the pandemic and the threat of war

El conjunto de ensayos que componen este libro han sido hechos en plena pandemia y procuran aportar a la memoria histórica latinoamericana y caribeña, además de ser un documento elaborado únicamente por mujeres, cuya sensibilidad y capacidad intelectual se unen con el fin de alertar a las lectoras y los lectores acerca de la peligrosidad del asedio contra la Revolución bolivariana, que pone en riesgo, sin duda alguna, la paz de toda la humanidad(AU)

Climatic influence on the risk of abdominal aortic aneurysm rupture.

Our aim is to examine the effects of climatic conditions on the incidence of ruptured abdominal aortic aneurysms (rAAA) in Catalonia, Spain. We combined clinical data from the Public Health official registries in Catalonia, Spain (HD-MBDS) of all rAAA with local climatic data obtained from the closest meteorological station (69 stations, National Meteorological Service: MeteoCat) from 2008 to 2017. We analyzed the median, maximum, minimum, and variability of atmospheric pressure (hPa) and air temperature (°C), solar irradiation (MJ/m2), humidity (%), accumulated precipitation (mm), median wind, and maximum flaw direction and velocity (°, m/s), recorded on the days of events, the previous day, and mean results for 3, 7, and 30 days before, as well as seasonality. Seventy-five control days were randomly selected in a 1-year period around every rAAA day at the same meteorological station, and compared. A total of 717 days and locations with rAAA were identified, and 53,775 controls were randomly selected. For the rAAA days, there were significantly lower temperatures, lower solar global irradiation, and higher mean humidity levels in all time periods (p < 0.001, p < 0.001, p < 0.05); higher atmospheric pressure variability during 1 week and 1 month before (p = 0.011, p = 0.007); and they often occurred during autumn/winter (57.6%, p < 0.001). Logistic regression identified low mean temperatures on the days of ruptures and high mean humidity the week before as independent rupture predictors. In conclusion, low median temperatures the same day and high humidity during 1 week before were identified as independent predictors of rAAA occurrence. The role of climate on pathophysiologic mechanisms may require further investigation.

Influence of On-Call Vascular Surgery Team and Off-Hour Effect on Survival after Ruptured Abdominal Aortic Aneurysm.

BACKGROUND: Ruptured abdominal aortic aneurysms (rAAAs) represent a life-threatening emergency and carry a high community and in-hospital mortality, despite treatment and protocol advances. Identifying prognostic factors like the presence of on-call vascular surgery teams at first hospital admissions or times of hospital admissions can modify hospital protocols and mechanisms to ameliorate general outcomes. The aim of this study is to analyze the influence of on-call vascular surgery teams and off-hour admissions on survival after rAAAs in Catalonia, Spain. METHODS: We used data from public health official registries (based on registration of the minimum basic data set) to collect diagnosed cases of rAAAs (ICD-9-CM [International Classification of Diseases, Ninth Revision, Clinical Modification] 441.3) between January 2008 and December 2017. Variables included patient comorbidities, aneurysm treatment and type (endovascular treatment: ICD-9-CM 39.7 or open surgery: ICD-9-CM 398.44 and 39.25), in-hospital mortality, initial hospital admissions and transfers, days and times of admission, and final treatment received. We compared intervention rates and mortalities in all samples and operated cases, in patients initially admitted into tertiary vascular centers (with on-call vascular surgery teams) and community centers (without on-call vascular surgery teams), and the "off-hour effect" (night [22:00 hr to 8:00 hr] or weekend admissions [Friday to Sunday]) in mortality and type of surgery (open or endovascular repair). RESULTS: Of 717 patients with rAAAs (92% men), 561 (78.2%) were initially admitted into tertiary vascular centers and 156 (21.8%) into community centers. The rate of operated cases and global mortality was higher when cases were initially admitted into tertiary vascular centers (388, 69.2% vs. 46, 29.5%; P < 0.001 and 63.6% vs. 88.5%, P < 0.001, respectively), but when surgery was performed (excluding palliative nonoperated cases), the postoperative mortality in both groups was comparable (47.4% vs. 60.9%, P = 0.085), in both univariate and multivariate analysis. On the other hand, patients admitted during night hours (210, 29.3%) did not reveal noteworthy differences in the overall mortality (68.6% vs. 69.2%, P = 0.860) or postoperative mortality compared to those admitted during day hours (61.0% vs. 60.4%, P = 0.880). Weekend admissions neither showed worse results (280, 39.1%, admitted during weekend: overall mortality 70.4% vs. 68.2%, P = 0.541 and postoperative mortality 51.2% vs. 47.3%, P = 0.436). No significant dissimilarities were seen either in the use of endovascular or open repair at night (42.2% vs. 46.1%, P = 0.457) or weekend (41.8% vs. 47%, P = 0.287). CONCLUSIONS: Patients with rAAAs initially admitted into tertiary vascular centers have better overall survival rates than those initially admitted into community centers, mainly because of higher rates of rejected cases in community centers. No differences were seen in terms of mortality or type of surgery in the off-hour admitted cases (night hours or during weekends).

Susceptibilidad del género aspergillus a los antifúngicos por el método de microdilución en caldo / Susceptibility of the aspergillus genus to antifungal agents by the broth microdilution method

La aspergilosis es una micosis ocasionada por el género Aspergillus que afecta tanto a pacientes inmunocompetentes como inmunosuprimidos. La presentación clínica depende del estado inmune del hospedero y de los factores de riesgo asociados; en la medida en que progrese la inmunosupresión habrá mayor probabilidad de adquirir la enfermedad invasora que se asocia a una elevada morbimortalidad. El objetivo de este trabajo fue Establecer la susceptibilidad del género Aspergillus a diferentes antifúngicos por el método de Microdilución en caldo según el documento M38-A2, con el fin de conocer los patrones de susceptibilidad de los aislados clínicos de Aspergillus spp. Se utilizaron 76 cepas clínicas que se encuentran en resguardo en la micoteca del Departamento de Micología del Instituto Nacional de Higiene "Rafael Rangel". Se utilizaron cepas controles A. fumigatus ATCC 204305, A. flavus ATCC 204304, C. parapsilosis ATCC 22019 y C. krusei ATCC 6258. Obteniendo como resultado que las CMI más elevadas in vitro frente a las 4 especies de Aspergillus fueron Voriconazol y AmB. Itraconazol y Caspofungina reportaron las CMI más bajas y por consiguiente los PCE obtenidos se encontraron entre más o menos 2 CMI comparadas con otras investigaciones. Este estudio aportó información importante sobre el comportamiento del género Aspergillus frente a los antifúngicos más utilizados en el tratamiento de la aspergilosis en nuestro país como a nivel mundial.

Aspergillosis is a mycosis caused by the genus Aspergillus that affects both immunocompetent and immunosuppressed patients. The clinical presentation depends on the host's immune status and the associated risk factors; As immunosuppression progresses, there is a greater probability of acquiring the invasive disease that is associated with high morbidity and mortality. The objective of this work was to establish the susceptibility of the genus Aspergillus to different antifungals by the method of Microdilution in broth according to document M38-A2, in order to know the susceptibility patterns of the clinical isolates of Aspergillus spp. Seventy-six clinical strains were used in the mycology department of the National Institute of Hygiene "Rafael Rangel". Control strains A. fumigatus ATCC 204305, A. flavus ATCC 204304, C. parapsilosis ATCC 22019 and C. krusei ATCC 6258 were used. As a result, the highest MICs in vitro against the 4 Aspergillus species were Voriconazole and AmB. Itraconazole and Caspofungin reported lower MICs and therefore the PCEs obtained were found between plus or minus 2 MICs compared to other investigations. This study provided important information about the behavior of the genus Aspergillus against the most commonly used antifungals in the treatment of aspergillosis in our country as a worldwide.

Inteligencias múltiples para propiciar prácticas de higiene bucal en dos grupos de escolares de primaria. Chiclayo, Perú / Multiple intelligences to promote oral hygiene practices in two groups of primary schoolchildren of Chiclayo, Peru

Objetivo. Determinar si la aplicación de sesiones educativas de salud bucal basadas en el enfoque de inteligencias múltiples logra mejorar las prácticas de higiene bucal en escolares de dos instituciones educativas de Chiclayo, Perú. Materiales y métodos. Se realizó un estudio de intervención comunitaria, con diseño cuasiexperimental orientado a evaluar las prácticas de higiene bucal de 87 escolares de las instituciones educativas Santa Julia y San José, evaluándolos antes y después de aplicar sesiones educativas de salud bucal, 42 de ellos participaron de sesiones con enfoque de inteligencias múltiples y 45 asistieron a sesiones tradicionales.Resultados. Las sesiones educativas que utilizaron enfoque de inteligencias múltiples contribuyeron a que 17 escolares de ambos colegios incrementen sus prácticas de higiene bucal y que 15 mejoren su índice de higiene oral, mientras que con el modelo tradicional solo lograron mejorar 4 y 3 escolares respectivamente, determinando significancia con la prueba de Mc Nemar (p < 0,001).Conclusiones. Con el modelo de sesión educativa con enfoque de inteligencias múltiples se consiguieron mayores y mejores prácticas de higiene bucal en los escolares, que con las sesiones tradicionales de salud bucal.

Objective. To determinate if the application of educational sessions about oral health based on multiple Intelligences approach will improve the oral hygiene practices in schoolchildren of two educational institutions from Chiclayo, Peru. Materials and methods. A community intervention study was made with quasiexperimental design oriented to assess the oral hygiene practices of 87 schoolchildren from Santa Julia and San Jose educational Institutions, evaluating them before and after applying the oral health education sessions, 42 of them participated in sessions focused on multiple intelligences approach and approximately 45 assisted to traditionalsessions. Results. The educational sessions that used multiple intelligences approach contributed with17 students of both schools to increase their oral hygiene practices and 15 to improve their oral hygiene indicator, while traditional model only improved 4 and 3 students oral hygiene respectively, determining significance difference with the Mc Nemar test (p < 0.001). Conclusions. With the educational session model focused on multiple intelligences approach, better and more oral hygiene practices in schoolchildren were reached than using traditional oral health sessions.

The Genboree Microbiome Toolset and the analysis of 16S rRNA microbial sequences.

BACKGROUND: Microbial metagenomic analyses rely on an increasing number of publicly available tools. Installation, integration, and maintenance of the tools poses significant burden on many researchers and creates a barrier to adoption of microbiome analysis, particularly in translational settings. METHODS: To address this need we have integrated a rich collection of microbiome analysis tools into the Genboree Microbiome Toolset and exposed them to the scientific community using the Software-as-a-Service model via the Genboree Workbench. The Genboree Microbiome Toolset provides an interactive environment for users at all bioinformatic experience levels in which to conduct microbiome analysis. The Toolset drives hypothesis generation by providing a wide range of analyses including alpha diversity and beta diversity, phylogenetic profiling, supervised machine learning, and feature selection. RESULTS: We validate the Toolset in two studies of the gut microbiota, one involving obese and lean twins, and the other involving children suffering from the irritable bowel syndrome. CONCLUSIONS: By lowering the barrier to performing a comprehensive set of microbiome analyses, the Toolset empowers investigators to translate high-volume sequencing data into valuable biomedical discoveries.

Probiotics and prebiotics to combat enteric infections and HIV in the developing world: a consensus report.

Infectious disease in the developing world continues to represent one of the greatest challenges facing humanity. Every year over a million children suffer and die from the sequela of enteric infections, while in 2008 it is estimated almost 2.7 million (UNAIDS 2009 update) adults and children became infected with human immunodeficiency virus (HIV). While oral rehydration therapy for diarrhea, and antiretrovirals (ARV) for HIV are critical, there is a place for adjunctive therapies to improve quality of life. The importance of the human microbiota in retaining health is now recognized, as is the concept of replenishing beneficial microbes through probiotic treatments. Studies have shown that probiotics can reduce the duration of diarrhea, improve gut barrier function, help prevent bacterial vaginosis (BV), and enhance immunity even in HIV-infected subjects. However, many issues remain before the extent of probiotic benefits can be verified, and their application to the developing world realised. This consensus report outlines the potential probiotic, and to a lesser extent prebiotic, applications in resource disadvantages settings, and recommends steps that could bring tangible relief to millions of people. The challenges to both efficacy and effectiveness studies in these settings include a lack of infrastructure and funding for scientists, students and research projects in developing countries; making available clinically proven probiotic and prebiotic products at affordable prices; and undertaking appropriately designed clinical trials. We present a roadmap on how efficacy studies may be conducted in a resource disadvantages setting among persons with chronic diarrhea and HIV. These examples and the translation of efficacy into effectiveness are described.

Gastrointestinal microbiome signatures of pediatric patients with irritable bowel syndrome.

BACKGROUND & AIMS: The intestinal microbiomes of healthy children and pediatric patients with irritable bowel syndrome (IBS) are not well defined. Studies in adults have indicated that the gastrointestinal microbiota could be involved in IBS. METHODS: We analyzed 71 samples from 22 children with IBS (pediatric Rome III criteria) and 22 healthy children, ages 7-12 years, by 16S ribosomal RNA gene sequencing, with an average of 54,287 reads/stool sample (average 454 read length = 503 bases). Data were analyzed using phylogenetic-based clustering (Unifrac), or an operational taxonomic unit (OTU) approach using a supervised machine learning tool (randomForest). Most samples were also hybridized to a microarray that can detect 8741 bacterial taxa (16S rRNA PhyloChip). RESULTS: Microbiomes associated with pediatric IBS were characterized by a significantly greater percentage of the class γ-proteobacteria (0.07% vs 0.89% of total bacteria, respectively; P < .05); 1 prominent component of this group was Haemophilus parainfluenzae. Differences highlighted by 454 sequencing were confirmed by high-resolution PhyloChip analysis. Using supervised learning techniques, we were able to classify different subtypes of IBS with a success rate of 98.5%, using limited sets of discriminant bacterial species. A novel Ruminococcus-like microbe was associated with IBS, indicating the potential utility of microbe discovery for gastrointestinal disorders. A greater frequency of pain correlated with an increased abundance of several bacterial taxa from the genus Alistipes. CONCLUSIONS: Using 16S metagenomics by PhyloChip DNA hybridization and deep 454 pyrosequencing, we associated specific microbiome signatures with pediatric IBS. These findings indicate the important association between gastrointestinal microbes and IBS in children; these approaches might be used in diagnosis of functional bowel disorders in pediatric patients.

Plasmid-mediated high-level gentamicin resistance among enteric bacteria isolated from pet turtles in Louisiana.

The sale of small turtles is banned by the Food and Drug Administration from the U.S. market due to concerns about their excretion of Salmonella spp. To produce a safe pet for the export market, the Louisiana pet turtle industry uses gentamicin sulfate baths (1,000 microg/ml) to eradicate Salmonella spp. from turtle eggs. In 1999, we analyzed bacterial samples recovered from turtle farms and found that strains of Salmonella enterica subsp. arizonae and other bacteria, such as Enterobacter cloacae, Citrobacter freundii, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia, were resistant to high concentrations of gentamicin (>2,000 microg/ml) and to other aminoglycosides. The goal of this study was to identify the gene(s) which contributes to the high-level gentamicin resistance phenotype observed in bacteria from environmental samples with turtle farming activity, particularly the salmonellae, and to estimate the incidence of such genes in these bacteria. R plasmids from gentamicin-resistant strains were transferred by conjugation and transformation to naive Escherichia coli cells. Cloning and sequencing of the gentamicin resistance determinants on these plasmids revealed the presence of the aminoglycoside acetyltransferase genes aac(3)-IIa and aac(3)-VIa; the latter was present as a gene cassette of a class 1 integron. Multiplex PCR assays showed that every gentamicin-resistant isolate carried one of these acetyltransferase genes. Pulsed-field gel electrophoresis and restriction enzyme digestion analysis of R plasmids carrying these genes revealed different restriction profiles and sizes, indicating a dissemination of the gentamicin resistance genes through mobile molecular elements. The data presented highlight the need to develop an alternate method for the eradication of Salmonella spp. from turtle eggs.