Transferable mechanisms of quinolone resistance are more frequent among enterotoxigenic Escherichia coli isolates displaying low-level quinolone resistance.

This study analysed the mechanisms of quinolone resistance among enterotoxigenic Escherichia coli (ETEC) in a periurban area of Lima, Peru. The susceptibility to nalidixic acid and ciprofloxacin, the role of Phe-Arg-b-Naphtylamyde inhibitable-(PAbN) efflux pumps, the presence of mutations in gyrA and parC as well as the presence of aac(6')Ib-cr, qepA, qnrA, qnrB, qnrC, qnrD, qnrVC and oqxAB were determined in 31 ETEC from previous case/control studies of children's diarrhoea. Discordances between disk diffusion, with all isolates showing intermediate or fully resistance to nalidixic acid, and minimal inhibitory concentration (MIC), with 7 isolates being below considered resistance breakpoint, were observed. Twenty-one isolates possessed gyrA mutations (19 S83L, 2 S83A). AAC(6') Ib-cr, QnrS, QnrB and QepA were found in 7, 6, 2 and 1 isolates respectively, with 3 isolates presenting 2 transferable mechanisms of quinolone resistance (TMQR) concomitantly. TMQR were more frequent among isolates with MIC to nalidixic acid ranging from 2 to 16 mg/L (p=0.03), while gyrA mutations were more frequent among isolates with nalidixic acid MIC >= 128 mg/L (p=0.0002). In summary, the mechanisms of quinolone resistance present in ETEC isolates in Peru have been described. Differences in the prevalence of underlying mechanisms associated with final MIC levels were observed. The results suggest two different evolutive strategies to survive in the presence of quinolones related to specific bacterial genetic background.

Transferable mechanisms of quinolone resistance are more frequent among enterotoxigenic Escherichia coli isolates displaying low-level quinolone resistance

@#This study analysed the mechanisms of quinolone resistance among enterotoxigenic Escherichia coli (ETEC) in a periurban area of Lima, Peru. The susceptibility to nalidixic acid and ciprofloxacin, the role of Phe-Arg-b-Naphtylamyde inhibitable-(PAbN) efflux pumps, the presence of mutations in gyrA and parC as well as the presence of aac(6’)Ib-cr, qepA, qnrA, qnrB, qnrC, qnrD, qnrVC and oqxAB were determined in 31 ETEC from previous case/control studies of children’s diarrhoea. Discordances between disk diffusion, with all isolates showing intermediate or fully resistance to nalidixic acid, and minimal inhibitory concentration (MIC), with 7 isolates being below considered resistance breakpoint, were observed. Twenty-one isolates possessed gyrA mutations (19 S83L, 2 S83A). AAC(6’) Ib-cr, QnrS, QnrB and QepA were found in 7, 6, 2 and 1 isolates respectively, with 3 isolates presenting 2 transferable mechanisms of quinolone resistance (TMQR) concomitantly. TMQR were more frequent among isolates with MIC to nalidixic acid ranging from 2 to 16 mg/L (p=0.03), while gyrA mutations were more frequent among isolates with nalidixic acid MIC > 128 mg/L (p=0.0002). In summary, the mechanisms of quinolone resistance present in ETEC isolates in Peru have been described. Differences in the prevalence of underlying mechanisms associated with final MIC levels were observed. The results suggest two different evolutive strategies to survive in the presence of quinolones related to specific bacterial genetic background.

The Prevalence, Correlates, Detection and Control of Diabetes among Older People in Low and Middle Income Countries. A 10/66 Dementia Research Group Population-Based Survey.

BACKGROUND: Little is known of the epidemiology of diabetes among older people in low and middle income countries. We aimed to study and compare prevalence, social patterning, correlates, detection, treatment and control of diabetes among older people in Latin America, India, China and Nigeria. METHODS: Cross-sectional surveys in 13 catchment area sites in nine countries. Diagnosed diabetes was assessed in all sites through self-reported diagnosis. Undiagnosed diabetes was assessed in seven Latin American sites through fasting blood samples (glucose > = 7 mmol/L). RESULTS: Total diabetes prevalence in catchment sites in Cuba (prevalence 24.2%, SMR 116), Puerto Rico (43.4%, 197), and urban (27.0%, 125), and rural Mexico (23.7%, 111) already exceeds that in the USA, while that in Venezuela (20.9%, 100) is similar. Diagnosed diabetes prevalence varied very widely, between low prevalences in sites in rural China (0.9%), rural India (6.6%) and Nigeria (6.0%). and 32.1% in Puerto Rico, explained mainly by access to health services. Treatment coverage varied substantially between sites. Diabetes control (40 to 61% of those diagnosed) was modest in the Latin American sites where this was studied. Diabetes was independently associated with less education, but more assets. Hypertension, central obesity and hypertriglyceridaemia, but not hypercholesterolaemia were consistently associated with total diabetes. CONCLUSIONS: Diabetes prevalence is already high in most sites. Identifying undiagnosed cases is essential to quantify population burden, particularly in least developed settings where diagnosis is uncommon. Metabolic risk factors and associated lifestyles may play an important part in aetiology, but this requires confirmation with longitudinal data. Given the high prevalence among older people, more population research is indicated to quantify the impact of diabetes, and to monitor the effect of prevention and health system strengthening on prevalence, treatment and control.

Resource Utilization and Temporal Segregation of Scarabaeinae (Coleoptera, Scarabaeidae) Community in a Caatinga Fragment.

We characterized dung beetles food preference and diel activity and examined the way such characteristics may structure a Scarabaeinae community in a dry forest. We sampled a fragment of Arboreal Caatinga in Milagres, Bahia, Brazil, during the dry and wet seasons, using baited pitfall (bovine spleen, human feces, cow dung, and rotten banana). Species were classified by activity (nocturnal and diurnal) and food preference (coprophagous, necrophagous, saprophagous, copro-necrophagous, and generalist). In total, 1,581 individuals belonging to 16 morphospecies were sampled, with six new records for Caatinga. The dung beetles were mainly from generalist and coprophagous species; seven species presented nocturnal activity, and five were diurnal. There was higher species richness during the day and greater abundance during the night. Species composition differences were influenced by functional guilds and beetle size according to temporal segregation. These factors may be related to physiological, morphological, and behavioral differences.

Short communication: Detection of Shiga toxin-producing Escherichia coli (STEC) in healthy cattle and pigs in Lima, Peru.

The aim of this study was to determine the prevalence of Shiga toxin-producing Escherichia coli (STEC) in cattle and pigs as a possible STEC reservoir in Lima, Peru. One hundred and fourteen cattle and 112 pigs from 10 and 4 farms, respectively, were studied. Five E. coli colonies per culture were studied by a multiplex real-time PCR to identify Shiga toxin-producing (stx1, stx2, eaeA), enterotoxigenic (lt, st), enteropathogenic (eaeA), enteroinvasive (ipaH), enteroaggregative (aggR), and diffusely adherent E. coli (daaD). Shiga toxin-producing E. coli were isolated from 16 cattle (14%) but none from pigs. stx1 was found in all bovine isolates, 11 of which also carried eaeA genes (69%); only 1 sample had both stx1 and stx2. Thirteen stx-positive strains were classified as Shiga-toxigenic (81%) using an enzymatic immunoassay, 2 STEC strains were from serogroup O157 (13%), and 7 were sorbitol negative (44%). Enteropathogenic E. coli were detected more frequently in cattle (18%, 20/114) than in pigs (5%, 6/112). To our knowledge, this is the first study on the prevalence of STEC in farms animals in Peru using molecular methods. Further studies are needed in a large number of farms to determine the relevance of these findings and its consequences for public health.

Genotypic and phenotypic characterization of enterotoxigenic Escherichia coli strains isolated from Peruvian children.

Enterotoxigenic Escherichia coli (ETEC) is a major cause of childhood diarrhea. The present study sought to determine the prevalence and distribution of toxin types, colonization factors (CFs), and antimicrobial susceptibility of ETEC strains isolated from Peruvian children. We analyzed ETEC strains isolated from Peruvian children between 2 and 24 months of age in a passive surveillance study. Five E. coli colonies per patient were studied by multiplex real-time PCR to identify ETEC virulence factors. ETEC-associated toxins were confirmed using a GM1-based enzyme-linked immunosorbent assay. Confirmed strains were tested for CFs by dot blot assay using 21 monoclonal antibodies. We analyzed 1,129 samples from children with diarrhea and 744 control children and found ETEC in 5.3% and 4.3%, respectively. ETEC was more frequently isolated from children >12 months of age than from children <12 months of age (P < 0.001). Fifty-two percent of ETEC isolates from children with diarrhea and 72% of isolates from controls were heat-labile enterotoxin (LT) positive and heat-stable enterotoxin (ST) negative; 25% and 19%, respectively, were LT negative and ST positive; and 23% and 9%, respectively, were LT positive and ST positive. CFs were identified in 64% of diarrheal samples and 37% of control samples (P < 0.05). The most common CFs were CS6 (14% and 7%, respectively), CS12 (12% and 4%, respectively), and CS1 (9% and 4%, respectively). ST-producing ETEC strains caused more severe diarrhea than non-ST-producing ETEC strains. The strains were most frequently resistant to ampicillin (71%) and co-trimoxazole (61%). ETEC was thus found to be more prevalent in older infants. LT was the most common toxin type; 64% of strains had an identified CF. These data are relevant in estimating the burden of disease due to ETEC and the potential coverage of children in Peru by investigational vaccines.

Study of the magnetocaloric properties of the antiferromagnetic compounds RGa2 (R = Ce, Pr, Nd, Dy, Ho and Er).

Magnetocaloric properties of antiferromagnetic RGa(2) (R = Ce, Pr, Nd, Dy, Ho and Er) compounds have been reported. These systems present an antiferromagnetic transition below 15 K and a field induced metamagnetic transition from the antiferromagnetic to ferromagnetic state. Our results show that the character of the magnetic field induced transition along the series affects the magnetocaloric properties. For the compounds with R = Ho, Dy and Er both negative and positive magnetocaloric effect (MCE) were observed above µ(0)ΔH = 2 T where the rate between negative and positive MCE contributions depends on how the magnetic transitions occur in these compounds. The evaluated values of maximum magnetocaloric properties of RGa(2) compounds are similar to other potential magnetic refrigerant materials reported in the literature.

Variable selection patterns on the labellum shape of Geoblasta pennicillata, a sexually deceptive orchid.

By mimicking shape and female mating pheromones, flowers of sexually deceptive orchids attract sexually excited males which pollinate them while trying to copulate. Although many studies have demonstrated the crucial importance of odour signals in these systems, most flowers pollinated by pseudocopulation resemble, at least superficially, an insect body and these visual cues may be important to cheat pollinators. In this 2-year study, we show that the shape of the labellum of Geoblasta pennicillata is a target of pollinator-mediated natural selection. Contrary to our expectations, plants with a labellum shape more similar to female wasps were not favoured. The strength and pattern of phenotypic selection varied between study years and sexual functions. Although selection through female success was probably associated to the fine-tuning of the mechanical fit between flower form and male wasp, shape was the target of natural selection through male success in both study years indicating that male wasps use this trait when choosing flowers. The imperfect mimicry and patterns of selection observed indicated that an exact imitation is not needed to attract and deceive the pollinators and they suggested a receiver perceptual bias towards uncommon phenotypes.

[Use of extra-hospital emergency systems in the treatment of acute stroke in the region of Murcia. Possible repercussions on the urgent care of stroke patients]. / Utilización del sistema de emergencias extrahospitalario en el tratamiento del ictus agudo en la región de Murcia. Posible repercusión en la asistencia sanitaria urgente del ictus.

AIM: To examine the use of extra-hospital emergency systems in the urgent care of stroke patients in our region and their influence on the time required to reach hospital, the time needed to perform an urgent computerised axial tomography (CAT) scan and the delay in receiving attention from the specialist. PATIENTS AND METHODS: Samples were collected from 232 stroke patients out of the total number admitted to our hospitals. Data about the stroke were collected prospectively, and included the arrival time, the time required to perform the CAT scan and the time the specialist devoted to attending the patient. Data were also gathered about the different extra-hospital transport and emergency systems. A statistical analysis was performed to determine the effect of using the extra-hospital emergency procedures on the different variables. RESULTS: A total of 53.6% of patients arrived within the first three hours. 38.7% went straight to hospital, 25% visited extra-hospital Emergency Services first, and 18.5% made a prior visit to Primary Care. 51.5% found their own way to the hospital and 46.7% arrived by ambulance. Mean time taken to perform an urgent CAT scan: 190.4 minutes; mean time required for specialist attention: 25.65 hours. The only statistically significant relation was the use of extra-hospital emergency systems and health care transport according to the type of stroke: both were more likely to be used in cases of haemorrhagic stroke. CONCLUSIONS: In hospitals in the Murcia region, the use of the extra-hospital emergency system and the means of transport utilised do not affect the time stroke patients take to reach hospital or the time needed to perform an urgent CAT scan or the delay in receiving attention from a specialist; the aetiology of the stroke does, however, influence the use of such services.

Utilización del sistema de emergencias extrahospitalario en el tratamiento del ictus agudo en la región de Murcia. Posible repercusión en la asistencia sanitaria urgente del ictus / Use of extra-hospital emergency system in the treatment of acute stroke in the region of murcia. Possible repercussions on the urgent care of stroke patients

Objetivo. Utilización en nuestra región de los sistemas de urgencias extrahospitalarias en la atención urgente del ictus y su influencia en el tiempo de llegada al hospital, el de realización de la tomografía axial computarizada (TAC) urgente y demora de la atención por el especialista. Pacientes y métodos. Se recogieron muestras de 232 pacientes con ictus del total de los ingresados en nuestros hospitales. Prospectivamente se recogieron datos sobre el ictus, con inclusión de los tiempos de llegada, tiempo de realización de la TAC y tiempo de atención por el especialista. Se recogió el uso delos distintos sistemas de urgencias y transporte extrahospitalarios. Estadísticamente se analizó la influencia del uso de los dispositivos de urgencia extrahospitalarios en las distintas variables recogidas. Resultados. 53,6% de los pacientes llegaron en las tres primeras horas. 38,7% acudieron directamente al hospital, el 25% acude primero al Servicio de Urgencias extrahospitalarias y 18,5% consulta previamente con Asistencia Primaria. El 51,5% llegaron por sus propios medios y el 46,7% en ambulancia. Tiempo medio de TAC urgente: 190,4 minutos; tiempo medio de atención por el especialista:25,65 horas. La única relación estadísticamente significativa fue el uso del sistema de urgencias extrahospitalarias y transporte sanitario según el tipo de ictus, con más tendencia a utilizarlos en los ictus hemorrágicos. Conclusiones. En los hospitales de Murcia, el uso del sistema de urgencias extrahospitalarias y el medio de transporte empleado no influyen en el tiempo de llegada del ictus al hospital, en el tiempo de realización de TAC urgente ni en la demora de atención por el especialista, y sí influye en la utilización de dichos servicios la etiología del ictus (AU)

Aim. To examine the use of extra-hospital emergency systems in the urgent care of stroke patients in our region and their influence on the time required to reach hospital, the time needed to perform an urgent computerised axial tomography(CAT) scan and the delay in receiving attention from the specialist. Patients and methods. Samples were collected from 232stroke patients out of the total number admitted to our hospitals. Data about the stroke were collected prospectively, and included the arrival time, the time required to perform the CAT scan and the time the specialist devoted to attending the patient. Data were also gathered about the different extra-hospital transport and emergency systems. A statistical analysis was performed to determine the effect of using the extra-hospital emergency procedures on the different variables. Results. A total of 53.6% of patients arrived within the first three hours. 38.7% went straight to hospital, 25% visited extra-hospital Emergency Services first, and 18.5% made a prior visit to Primary Care. 51.5% found their own way to the hospital and 46.7% arrived by ambulance. Mean time taken to perform an urgent CAT scan: 190.4 minutes; mean time required for specialist attention: 25.65hours. The only statistically significant relation was the use of extra-hospital emergency systems and health care transport according to the type of stroke: both were more likely to be used in cases of haemorrhagic stroke. Conclusions. In hospitals in the Murcia region, the use of the extra-hospital emergency system and the means of transport utilised do not affect the time stroke patients take to reach hospital or the time needed to perform an urgent CAT scan or the delay in receiving attention from a specialist; the aetiology of the stroke does, however, influence the use of such services (AU)

[Morphological characterization of annatto fruits 9bixa orellana L.) and its correspondence with protein and isoenzym patterns]. / Caracterización morfológica de frutos de onoto (Bixa orellana L.) y su correspondencia con patrones de proteínas e isoenzimas.

A group of 32 annatto genotypes collected in five Venezuelan regions (Oriente, Centro, Llanos, Andes and Amazonas) and in Brazil were used for morphological studies. The fruit variables with the greatest discriminatory power in the formation of groups were capsule size, spinosity and seed size. On the other hand, an association group among the variables spinosity, spine length, dehiscence and apex shape were formed, also a proportional association between capsule and seed size, and between dehiscent capsule and brown coloured seeds. Additionally, in order to discriminate morphological variables behaviour in respond to electrophoretic variables, a group of protein and isozyme bands associated with fruit characteristics were established. Therefore, a classification system of this species was possible using morphological studies of the capsules, even though a determined association relating morphological and molecular patterns was not found.

[Identification and genetic variability of annatto genotypes (Bixa orellana L.) by means of hydrosoluble proteins and isoenzymes]. / Identificación y variabilidad genética de genotipos de onoto (Bixa orellana L.) mediante el uso de proteínas hidrosolubles e isoenzimas.

In order to identify and to determine the genetic variability of 36 annatto genotypes (Bixa orellana L.) collected in five Venezuelan regions (Oriente, Centro, Llanos, Andes and Amazonas) and in Brazil, hydrosoluble protein patterns as well as specific isozyme patterns (alpha-esterase, beta-esterase and peroxidase) were studied using extracts of germinated annatto seeds with radicles of 10 to 15 mm long. Each electrophoretic system allowed genotype discrimination by means of unique banding patterns: both the hydrosoluble protein and the electrophoretic system of beta-esterase with nine banding patterns each; whilst alpha-esterase and peroxidase discriminated eight and three genotypes, respectively. On the other hand, a combination of all the systems permitted a greater discrimination since 34 out of 36 genotypes could be distinguished. Eight mayor groups were formed that showed high levels of genetic diversity (40 to 60%) with no association between geographic and genetic distances, probably because of human influence in the aleatory distribution of this crop. Results obtained indicated that using electrophoretic banding patterns, a classification system could be established for identification and genetic variability purposes in this species.

Delayed gastric emptying and gastroesophageal reflux: a pathophysiologic relationship.

BACKGROUND: Delayed gastric emptying (DGE) is frequent in patients with gastroesophageal reflux (GER), but its pathophysiologic role has not yet been established. To identify a relationship between DGE and GER, we assessed whether DGE increases esophageal acid exposure and the related importance of possible mechanisms. METHODS: Thirty pediatric patients with pathological GER were divided according to gastric emptying scintigraphy into a DGE group (n = 14) and normal-emptying group (n = 16). The esophageal pH-monitoring parameters of the two groups were compared with respect to the individual variation between postprandial and fasting periods. RESULTS: Patients with DGE had less total acid exposure than did those with normal emptying, but patients in both groups had a pathological fraction of time when pH was below 4 in both the postprandial (median: 18 vs. 27.6; P = 0.49) and fasting (8.5 vs. 23.9; P = 0.01) periods. Patients in the normal-emptying group had similar fraction of time when pH was below 4 in the postprandial and fasting periods. However, patients in the group with DGE had a fraction of time when pH was below 4 in the postprandial period that was almost double that presented in fasting period (postprandial to fasting ratio: 2.11:0.90; P = 0.002). The postprandial to fasting ratio for episodes per hour was similar in the two groups (1.81 vs. 1.79; P = 0.62). Patients with DGE had a significantly higher frequency of long episodes in the postprandial period than did those with normal emptying (62.5% vs. 38.2%; P = 0.04). The occurrence of the longest episode in the postprandial period was also significantly higher for patients with DGE (57.1% vs. 6.2%; P = 0.003). CONCLUSIONS: DGE seems to accentuate postprandial reflux by increasing the volume of refluxate per episode of reflux through an underlying incompetent lower esophageal sphincter.

Startle reactivity and PTSD symptoms in a community sample of women.

Exaggerated startle and PTSD symptoms have been investigated primarily in relation to acute or Type I stressors. The present study examined PTSD symptoms and startle eyeblink response in relation to chronic or Type II stressors. Type II stressors were operationally defined as high levels of childhood corporal punishment and high levels of current partner aggression. This study recruited a sample of 52 women from a metropolitan community and administered several questionnaires assessing experience of corporal punishment in childhood, current intimate partner aggression and level of PTSD symptoms. Following questionnaires, women were presented with eight auditory startle probes (white noise). Results showed that both childhood corporal punishment and intimate partner aggression were associated with women's PTSD symptom scores. However, only PTSD symptom scores were associated with reduced startle. Results are discussed in light of Type I and Type II stressors, and recent suggestions in the PTSD literature that a subgroup of individuals may experience physiological suppression rather than heightened physiological reactivity.

Síndrome serotoninérgico / Serotonin syndrome

El avance en el conocimiento del mecanismo de acción de los neurotransmisores, el descubrimiento de nuevos receptores y de sus interrelaciones permite ir aclarando la etiopatogenia de los diferentes trastornos cerebrales. El uso cada vez más frecuente de los inhibidores de la recaptación de la serotonina, y de serotoninérgicos en general, ha provocado un aumento en la incidencia de un cuadro, potencialmente mortal, denominado síndrome serotoninérgico central. Este síndrome, de incidencia desconocida, caracterizado por afectación global del estado general (alteraciones del estado mental, neuromuscular y autonómico) se confunde con otros cuadros, y es infradiagnosticado, demorándose con frecuencia su tratamiento. Presentamos una revisión de este tema a propósito de un caso (AU)

Alcohol y juventud: aspectos sociológicos / Alcohol and youth: sociological aspects

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Metastatic thyroid carcinoma arising from congenital goiter due to mutation in the thyroperoxidase gene.

A very large cervical tumor that extended to the upper mediastinum was seen in a newborn after an uneventful pregnancy. The computed axial tomography scan confirmed the presence of a solid mass with precise limits and scattered foci of calcifications situated in the anterolateral region of the neck. The infant underwent thyroidectomy on the seventh day after birth. Pathological examination revealed a follicular carcinoma of the thyroid and probable dyshormonogenetic hyperplastic goiter. At 5 months of age, whole body scans indicated the presence of lung and bone metastases, which were treated with therapeutic doses of radioiodine. Genomic DNA was obtained from the newborn, her parents, her paternal aunt, and her paternal grandparents. Denaturing gradient gel electrophoresis analysis of PCR fragments corresponding to exon 14 of the thyroid peroxidase (TPO) gene indicated the presence of a mutant TPO allele present in the propositus, her father, and her paternal grandmother. Sequencing of the TPO gene demonstrated a mutation resulting from an insertion of a single extra cytosine in a stretch of seven cytosines at positions 2505-2511. The insertion caused a frame shift and a stop signal in exon 16. This sequence would translate into a structurally modified and probably inactive TPO protein. We conclude that the aggressive thyroid metastatic carcinoma arose from a dyshormonogenetic goiter caused by a defective TPO protein.

The nuts and bolts of behavioral observation of marital and family interaction.

Despite considerable discussion in the literature about the advantages of observational research and the relative benefits of different coding systems and strategies, little is written about the actual implementation of this assessment strategy. This paper presents an overall framework as well as the essential components involved in collecting (selection of task, setting, unit of analysis, and coding system) and coding (transcribing, selecting and training coders, transforming data, and analyzing reliability) of observational data. To achieve success with observational methods, we emphasize several issues, including (a) the research question as the motivator for all decisions, (b) the interrelatedness of tasks, and (c) the implications of decisions early in the process for later stages of analysis and interpretation. Investigators are encouraged to communicate the details of their observational and coding procedures so that these methods are readily accessible for purposes of replication and comparison.