Retrospective cohort study analyzing outcomes of the SIGN Fin Nail in adult femoral fractures using the retrograde approach.

Purpose: There is high burden of long bone fractures in low- and middle-income countries (LMICs). Given a limited availability of fluoroscopy in LMICs, the Surgical Implant Generation Network (SIGN) developed two types of intramedullary nails: the SIGN standard nail and the SIGN Fin Nail. A limited number of studies have analyzed healing outcomes with the SIGN Fin Nail and the current study is the largest one to date. The purpose of this study is to compare outcomes between the SIGN standard nail and SIGN Fin Nails in adult femoral shaft fractures treated with a retrograde approach. Method: A retrospective cohort study of adults with femoral shaft fractures was performed using the Sign Online Surgical Database (SOSD). The primary outcome was achieving full painless weight bearing and the secondary outcomes assessed were radiographic healing and infection. A propensity-score adjustment was performed for potential confounders and effect modification due to fracture location was tested using a Mantel-Haenszel test for heterogeneity. Results: Of 19,928 adults with femoral shaft fractures, 2,912 (14.7%) had the required 6-month follow-up to be included. The overall propensity score weighted relative risk between the Fin and Standard Nail for achieving painless weight-bearing was 0.99, 95% CI [0.96-1.03] and for radiographical healing was 0.99, 95%CI [0.97-1.02]. The propensity score weighted relative risk for infection was 1.30, 95% [0.85-1.97]. Use of the Fin nail was also significantly associated with shorter surgery times (p < 0.005, effect size = 24 min). Sub-group analysis based on fracture location and injury cause demonstrated no change in relative risk. Conclusion: The Fin nail showed no change in relative risk in terms of achieving full painless weightbearing or radiographic healing compared to the standard nail for retrograde nailing of femoral shaft fractures in adults. The heterogeneous nature of the cohort and large sample size allow for generalizability and add to a growing base of literature supporting use of the Fin Nail for retrograde femoral nailing. However, there are limitations as we could not correct for comminution at the fracture site or measure radiographic alignment or shortening.

Caveolae-associated cAMP/Ca2+-mediated mechano-chemical signal transduction in mouse atrial myocytes.

Caveolae are tiny invaginations in the sarcolemma that buffer extra membrane and contribute to mechanical regulation of cellular function. While the role of caveolae in membrane mechanosensation has been studied predominantly in non-cardiomyocyte cells, caveolae contribution to cardiac mechanotransduction remains elusive. Here, we studied the role of caveolae in the regulation of Ca2+ signaling in atrial cardiomyocytes. In Langendorff-perfused mouse hearts, atrial pressure/volume overload stretched atrial myocytes and decreased caveolae density. In isolated cells, caveolae were disrupted through hypotonic challenge that induced a temporal (<10 min) augmentation of Ca2+ transients and caused a rise in Ca2+ spark activity. Similar changes in Ca2+ signaling were observed after chemical (methyl-ß-cyclodextrin) and genetic ablation of caveolae in cardiac-specific conditional caveolin-3 knock-out mice. Acute disruption of caveolae, both mechanical and chemical, led to the elevation of cAMP level in the cell interior, and cAMP-mediated augmentation of protein kinase A (PKA)-phosphorylated ryanodine receptors (at Ser2030 and Ser2808). Caveolae-mediated stimulatory effects on Ca2+ signaling were abolished via inhibition of cAMP production by adenyl cyclase antagonists MDL12330 and SQ22536, or reduction of PKA activity by H-89. A compartmentalized mathematical model of mouse atrial myocytes linked the observed changes to a microdomain-specific decrease in phosphodiesterase activity, which disrupted cAMP signaling and augmented PKA activity. Our findings add a new dimension to cardiac mechanobiology and highlight caveolae-associated cAMP/PKA-mediated phosphorylation of Ca2+ handling proteins as a novel component of mechano-chemical feedback in atrial myocytes.

Allosteric modulation of ryanodine receptor RyR1 by nucleotide derivatives.

The coordinated release of Ca2+ from the sarcoplasmic reticulum (SR) is critical for excitation-contraction coupling. This release is facilitated by ryanodine receptors (RyRs) that are embedded in the SR membrane. In skeletal muscle, activity of RyR1 is regulated by metabolites such as ATP, which upon binding increase channel open probability (Po). To obtain structural insights into the mechanism of RyR1 priming by ATP, we determined several cryo-EM structures of RyR1 bound individually to ATP-γ-S, ADP, AMP, adenosine, adenine, and cAMP. We demonstrate that adenine and adenosine bind RyR1, but AMP is the smallest ATP derivative capable of inducing long-range (>170 Å) structural rearrangements associated with channel activation, establishing a structural basis for key binding site interactions that are the threshold for triggering quaternary structural changes. Our finding that cAMP also induces these structural changes and results in increased channel opening suggests its potential role as an endogenous modulator of RyR1 conductance.

Surgical stabilization of rib fractures in patients with pulmonary comorbidities.

INTRODUCTION: Prior studies have shown that the surgical stabilization of rib fractures (SSRF) for patients with multiple rib fractures is associated with improved outcomes by restoring chest wall integrity and decreasing time to return to prior functional status. It is unclear if patients with pulmonary comorbidities (PCM) would benefit from this procedure. OBJECTIVE: To compare the difference in morbidity and mortality of patients with multiple rib fractures undergoing SSRF who have underlying PCM to those who do not have PCM. METHODS: We performed a retrospective cohort study of patients with multiple rib fractures using data from the Trauma Quality Improvement Program (January 2015 to December 2018). Patients with penetrating injuries, those who died within the first 24 h, those with substantial head, spine, or abdominopelvic injuries, and those who were pregnant, were excluded. A PCM was defined as chronic lower respiratory disease, active smoking, or morbid obesity. Dichotomous outcomes were adjusted for potential confounders by creating a propensity score for PCM and applying inverse probability weighting. The propensity score accounted for multiple patient-level and hospital level covariates. Continuous outcomes were adjusted for these same covariates using multivariable quantile regression. RESULTS: Of the 4,084 patients who underwent SSRF, 3048 (75%) were males, the median age was 57 years [IQR 47, 66], and 1504 (37%) had at least one PCM. After adjusting for the propensity score, patients with PCM who underwent SSRF had no significant difference in mortality compared to those without PCM (absolute difference, 0.7% [95% CI -0.2, 1.7]). Similarly, there was no significant difference in time on the ventilator (0.6 days [-0.1, 1.4]). Patients with PCM, however, had a statistically significantly longer hospital LOS (0.8 days [0.3, 1.3]) and ICU LOS (0.6 days [0.1, 1.1]), higher risk of tracheostomy (2.7% [0.1, 4.6]) and higher probability of pulmonary complications (2.7% [1.2, 4.2]), compared to those without PCM. CONCLUSION: Among patients with multiple rib fractures who undergo SSRF, having a PCM did not result in a clinically important higher probability of dying or experiencing substantial morbidity. This factor should not exclude patients with PCM from receiving SSRF for multiple rib fractures but the small increased risk in morbidity should be discussed with patients prior to SSRF.

Antibody and Memory B-Cell Immunity in a Heterogeneously SARS-CoV-2-Infected and -Vaccinated Population.

Global population immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is accumulating through heterogeneous combinations of infection and vaccination. Vaccine distribution in low- and middle-income countries has been variable and reliant on diverse vaccine platforms. We studied B-cell immunity in Mexico, a middle-income country where five different vaccines have been deployed to populations with high SARS-CoV-2 incidences. Levels of antibodies that bound a stabilized prefusion spike trimer, neutralizing antibody titers, and memory B-cell expansion correlated with each other across vaccine platforms. Nevertheless, the vaccines elicited variable levels of B-cell immunity, and the majority of recipients had undetectable neutralizing activity against the recently emergent omicron variant. SARS-CoV-2 infection, experienced before or after vaccination, potentiated B-cell immune responses and enabled the generation of neutralizing activity against omicron and SARS-CoV for all vaccines in nearly all individuals. These findings suggest that broad population immunity to SARS-CoV-2 will eventually be achieved but by heterogeneous paths. IMPORTANCE The majority of studies on SARS-CoV-2 vaccine-elicited immunity and immune evasion have focused on single vaccines corresponding to those distributed in high-income countries. However, in low- and middle-income countries, vaccine deployment has been far less uniform. It is therefore important to determine the levels of immunity elicited by vaccines that have been deployed globally. Such data should help inform policy. Thus, this paper is very much a "real-world" study that focuses on a middle-income country, Mexico, in which five different vaccines based on mRNA, adenovirus, and inactivated-virus platforms have been extensively deployed, while (as documented in our study) SARS-CoV-2 variants with increasing degrees of immune evasiveness have propagated in the Mexican population, culminating in the recent emergence of B.1.1.529 (omicron).

After PCI and short-term DAPT, P2Y12 inhibitors alone vs. ongoing DAPT reduce major bleeding; CV events do not differ.

SOURCE CITATION: Malik AH, Yandrapalli S, Shetty SS, et al. Meta-analysis of dual antiplatelet therapy versus monotherapy with P2Y12 inhibitors in patients after percutaneous coronary intervention. Am J Cardiol. 2020;127:25-9. 32389351.

Variación estacional y características fisicoquímicas e hidrológicas que influyen en los macroinvertebrados acuáticos, en un río tropical

Introducción: La distribución de los macroinvertebrados acuáticos en los ríos puede estar determinada por el tipo del sustrato, la forma del canal del río, el régimen hidrológico y las interacciones con factores bióticos y abióticos. En Costa Rica se desconoce en gran parte de los ríos, las variaciones en la distribución de los macroinvertebrados acuáticos producto de las transiciones y consecuentes variaciones en características fisicoquímicas e hidrológicas. Objetivos : 1) Estudiar el cambio del ensamblaje de macroinvertebrados acuáticos en dos sitios dentro del cauce del Río Naranjo, durante los cuatro periodos hidrológicos del año; 2) determinar la relación entre las variables fisicoquímicas, sustrato y el caudal con el ensamblaje. Metodología: El estudio se realizó en el Río Naranjo, Costa Rica, en dos sitios de muestreo durante un año, evaluando los cuatro periodos hidrológicos del año. En cada sitio de muestreo se obtuvieron valores de velocidad y profundidad del agua, caudal, oxígeno disuelto, pH, conductividad, sulfatos, amonio, nitrato, silicatos, fosfatos y sustrato, y se obtuvo una muestra de macroinvertebrados acuáticos por cada tipo de microhábitat determinado por la velocidad del agua. Se realizó una prueba PERMANOVA de dos vías, para determinar si existe una diferencia entre la abundancia de macroinvertebrados acuáticos, por periodo y entre sitios. Se hizo un análisis de correspondencia canónica para observar la relación entre los macroinvertebrados acuáticos y los factores ambientales. Por último, se realizó una prueba de Spearman para determinar la relación positiva o negativa de las variables con los macroinvertebrados Resultados: Hubo una mayor abundancia durante la estación seca, mientras que durante la transición de la estación seca a la lluviosa se registró la menor abundancia de organismos. El ACC indicó que el primer eje presentó una relación positiva con el sustrato limo y arena, y una relación negativa para las variables velocidad de corriente y sustrato rocoso. El segundo eje presentó una relación positiva con el caudal y los nitratos, y negativa para el sustrato canto rodado. La mayoría de los organismos mostraron una respuesta negativa al aumento del flujo y los nitratos. Discusión: Conforme aumenta el caudal, aumenta la velocidad del agua y no todos los organismos registrados en el Río Naranjo cuentan con características para sobrevivir a estas condiciones. Además, la profundidad también aumenta junto con la fuerza de arrastre, provocando el movimiento de los sustratos de menor tamaño y una remoción de organismos. El aumento de nitratos puede generar una disminución de los organismos más sensibles como Plecoptera y Ephemeroptera. A pesar de las variaciones fisicoquímicas y de caudal registradas en el Río Naranjo, éstas no fueron lo suficientemente fuertes como para variar el ensamblaje de macroinvertebrados acuáticos, por lo que la cuenca por el momento no cuenta con factores estresantes que elimine organismos durante uno o varios meses del año.

Introduction: The distribution of aquatic macroinvertebrates in rivers may be determined by the type of substrate, the shape of the river channel, the hydrological regime, and interactions with biotic and abiotic factors. Variations in the distribution of aquatic macroinvertebrates due to transitions and variations in physicochemical and hydrological characteristics are unknown in most rivers. Objectives: 1) to study the change in the aquatic macroinvertebrates assemblages in two sites in Naranjo River, during the four hydrological seasons; 2) to determine the relationship between the physicochemical variables, substrate and flow with the assemblages. Methodology: The study was conducted in the Naranjo River, Costa Rica, at two sampling sites during one year, evaluating the four seasons of the year. In each station we measure, values of water velocity and depth, flow rate, dissolved oxygen, pH, conductivity, sulfates, ammonium, nitrate, silicates, phosphates, and substrate were obtained, and a sample of aquatic macroinvertebrates was obtained for each type of microhabitat determined by water velocity. Two-way PERMANOVA was made to determine if there is a difference among aquatic macroinvertebrate abundance, per period and between sites. Canonical correspondence analysis was used to observe the relationship between aquatic macroinvertebrates and environmental factors. Finally, a Spearman's rank correlation coefficient was performed to determine the positive or negative relationship of variables with macroinvertebrates. Results: There was a greater abundance during the dry season, while during the transition from dry to the rainy season, the lowest abundance of organisms was recorded. The CCA indicates that the first axis presented a positive relationship with the silt and sand substrate and a negative relationship for the current velocity and rock substrate variables. The second axis showed a positive relationship with flow and nitrates and negative for the pebble substrate. Most organisms showed a negative response to increased flow and nitrates. Discussion: As flow increases, current velocity increases, and not all organisms recorded in the Naranjo River have the characteristics to survive these conditions. In addition, the depth also increases along with the drag force, causing movement of smaller substrates and removal of organisms. Increased nitrates can lead to a decrease in more sensitive organisms, such as Plecoptera and Ephemeroptera. In spite of the physicochemical and flow variations registered in the Naranjo River, these were not strong enough to vary the assemblages of aquatic macroinvertebrates, so the basin does not have stressful factors that eliminate organisms during one or several months of the year.

Colonización de macroinvertebrados acuáticos en tres tipos de sustratos artificiales, en un río tropical

Introducción: Existen diferentes metodologías para la recolecta de macroinvertebrados acuáticos (p.e., la red D y Red Surber), sin embargo, algunas de estas no son efectivas en todos los cuerpos de agua o representa un riesgo para la persona que adquiere la muestra. Los sustratos artificiales pueden emplearse en ríos profundos, contaminados o con presencia de cocodrilos. En Costa Rica hay estudios donde se utilizó los sustratos artificiales, para determinar la riqueza y abundancia en humedales tipo lago y lagunas, no obstante se desconoce la efectividad de un tipo de sustrato sobre otro y en sistemas lóticos. El objetivo del estudio fue demostrar la efectividad de tres tipos de sustratos artificiales. Métodos: las muestras se obtuvieron de manera bimensual entre los años 2013 y 2017, en el Río Parismina, Costa Rica, en cuatro sitios a lo largo del río y se evaluó los sustratos piedra, madera y hojas. Se aplicó una prueba de Kruskal-Wallis para determinar las diferencias entre la abundancia y el tipo de sustrato, como también para determinar la diferencia entre la abundancia y el sitio de muestreo. Además, para determinar si existe una diferencia entre los sustratos por sitio, se aplicó una prueba Permanova de dos vías. Un análisis de correspondencia múltiple para determinar el grado de asociación de la comunidad con respecto al tipo de sustrato. Resultados: Un total de 1159 organismos fueron recolectados, siendo Diptera y Ephemeroptera los órdenes más abundantes. La madera y hojas fueron los sustratos con mayor biodiversidad, como también los sitios con mayor vegetación. Conclusiones: El uso en conjunto de los tres tipos de sustratos artificiales, es efectivo para obtener una mayor riqueza de organismos, ya que se observó afinidad por un sustrato según el género de macroinvertebrado acuático.

Introduction: Different methodologies exist for sampling aquatic macroinvertebrates, however, some of these (e.g., kick-net, Surber) are not well suited for deep, contaminated rivers or rivers with presence of crocodiles, which represent a risk to the person who must take the sample. One alternative is to use artificial substrates. The use of artificial substrates to evaluate the aquatic macroinvertebrate biodiversity in wetlands has been studied previously in Costa Rica, but no research has been conducted to determine which types of substrates are most effective. The present study aimed to evaluate the effectiveness of three artificial substrates (i.e., stones, leaves and wood). Methods: Samples of the three substrates were taken bi-monthly between 2013 and 2017 in four sites of the Parismina River. A Kruskal-Wallis test was applied to determine differences between the macroinvertebrate abundance among substrate type. Beside to determine if there is a difference between substrates per site, a two-way PERMANOVA test was applied and a multiple correspondence analysis was used to correlate the substrate type with the macroinvertebrate community. Results: A total of 1 159 organisms were collected, with Diptera and Ephemeroptera being the most abundant. Wood and leaves were the substrates with greatest biodiversity and abundance of organisms; in addition the two sites with greatest vegetation were the most diverse. Conclusions: Most of the organisms were registered on any of the three types of artificial substrates, thus we recommend the joint use of the three types of substrates for biomonitoring or taxa richness studies.

Disruption of Ca2+i Homeostasis and Connexin 43 Hemichannel Function in the Right Ventricle Precedes Overt Arrhythmogenic Cardiomyopathy in Plakophilin-2-Deficient Mice.

BACKGROUND: Plakophilin-2 (PKP2) is classically defined as a desmosomal protein. Mutations in PKP2 associate with most cases of gene-positive arrhythmogenic right ventricular cardiomyopathy. A better understanding of PKP2 cardiac biology can help elucidate the mechanisms underlying arrhythmic and cardiomyopathic events consequent to PKP2 deficiency. Here, we sought to capture early molecular/cellular events that can act as nascent arrhythmic/cardiomyopathic substrates. METHODS: We used multiple imaging, biochemical and high-resolution mass spectrometry methods to study functional/structural properties of cells/tissues derived from cardiomyocyte-specific, tamoxifen-activated, PKP2 knockout mice (PKP2cKO) 14 days post-tamoxifen injection, a time point preceding overt electrical or structural phenotypes. Myocytes from right or left ventricular free wall were studied separately. RESULTS: Most properties of PKP2cKO left ventricular myocytes were not different from control; in contrast, PKP2cKO right ventricular (RV) myocytes showed increased amplitude and duration of Ca2+ transients, increased Ca2+ in the cytoplasm and sarcoplasmic reticulum, increased frequency of spontaneous Ca2+ release events (sparks) even at comparable sarcoplasmic reticulum load, and dynamic Ca2+ accumulation in mitochondria. We also observed early- and delayed-after transients in RV myocytes and heightened susceptibility to arrhythmias in Langendorff-perfused hearts. In addition, ryanodine receptor 2 in PKP2cKO-RV cells presented enhanced Ca2+ sensitivity and preferential phosphorylation in a domain known to modulate Ca2+ gating. RNAseq at 14 days post-tamoxifen showed no relevant difference in transcript abundance between RV and left ventricle, neither in control nor in PKP2cKO cells. Instead, we found an RV-predominant increase in membrane permeability that can permit Ca2+ entry into the cell. Connexin 43 ablation mitigated the membrane permeability increase, accumulation of cytoplasmic Ca2+, increased frequency of sparks and early stages of RV dysfunction. Connexin 43 hemichannel block with GAP19 normalized [Ca2+]i homeostasis. Similarly, protein kinase C inhibition normalized spark frequency at comparable sarcoplasmic reticulum load levels. CONCLUSIONS: Loss of PKP2 creates an RV-predominant arrhythmogenic substrate (Ca2+ dysregulation) that precedes the cardiomyopathy; this is, at least in part, mediated by a Connexin 43-dependent membrane conduit and repressed by protein kinase C inhibitors. Given that asymmetric Ca2+ dysregulation precedes the cardiomyopathic stage, we speculate that abnormal Ca2+ handling in RV myocytes can be a trigger for gross structural changes observed at a later stage.

A Case of Acute Pancreatitis Associated with Early-Stage Adenocarcinoma of the Gallbladder.

BACKGROUND Gallstones are a common cause of acute pancreatitis. The proposed mechanism by which choledocholithiasis induces pancreatitis is mechanical obstruction of the ampulla leading to the reflux of bile into the pancreatic duct or edema resulting from a gallstone's passage. To our knowledge, there are no previously reported cases of gallbladder adenocarcinoma as a potential cause of acute pancreatitis. Herein, we describe a patient who presented with acute necrotizing pancreatitis, without other associated risk factors, who was found to have a fragmented friable polypoid gallbladder adenocarcinoma. CASE REPORT A 55-year old Hispanic female with prediabetes presented to the Emergency Department with severe epigastric abdominal pain radiating to her back. The patient's clinical presentation, laboratory tests and computed tomography imaging were suggestive of acute necrotizing pancreatitis and a gallbladder lesion concerning for neoplasm. After clinical resolution of her pancreatitis, the patient was brought to the operating room for a cholecystectomy. Final pathology revealed a stage T1aN0 gallbladder adenocarcinoma. CONCLUSIONS We have presented a patient with acute necrotizing pancreatitis in the absence of alcohol abuse, gallstones, biliary sludge, hypertriglyceridemia, hypercalcemia, or hereditary predisposition. Without evidence of other etiologies, we hypothesize that the friable tumor fragments of the gallbladder adenocarcinoma might be the underlying cause of pancreatitis in this patient.

Polimorfismos del gen Arsénico 3 Metiltransferasa (As3MT) y la eficiencia urinaria del metabolismo del arsénico en una población del norte de México / Polymorphisms of the Arsenite Methyltransferase (As3MT) gene and urinary efficiency of arsenic metabolism in a population in northern Mexico

RESUMEN El objetivo del estudio fue evaluar la relación de los polimorfismos rs11191439 y rs3740393 del gen Arsénico 3 Metiltransferasa (As3MT) con los perfiles de excreción urinaria de arsénico, en una población del norte de México. Se realizó un estudio transversal con 102 participantes de 14 a 75 años en la Comarca Lagunera, México. Se determinó la especiación de los metabolitos urinarios de arsénico y extracción de ADN, el análisis y amplificación de los polimorfismos se realizó por PCR tiempo real. Se realizó un análisis descriptivo y se evaluó las diferencias en las concentraciones de arsénico urinario por sexo y genotipo. La mediana de concentración de arsénico en el agua fue de 82 μg/L, los niveles de excreción urinaria del ácido dimetilarsínico (DMA) fueron más altos en mujeres que en los hombres. Los portadores de la variante genética CC del gen As3MT (rs3740393) presentaron concentraciones urinarias superiores de ácido monometilarsónico (p=0,01) y DMA (p=0,05).

ABSTRACT The aim of this study was to assess the relationship of the rs11191439 and rs3740393 polymorphisms of the Arsenite Methyltransferase (As3MT) gene with the arsenic urinary excretion profiles in a population in northern Mexico. A crosssectional study was conducted with 102 participants between the ages of 14 and 75 in Comarca Lagunera, Mexico. Speciation of the arsenic urinary metabolites was determined, and DNA was extracted; analysis and amplification of the polymorphisms was made by PCR in real time. A descriptive analysis was carried out and the differences in the urinary arsenic concentrations were assessed according to sex and genotype. The median concentration of arsenic in water was 82 μg/L; the levels of urinary excretion of dimethylarsinic acid (DMA) were higher in women than in the men. The carriers of the CC genetic variant of the As3MT (rs3740393) gene showed higher urinary concentrations of methylarsinic acid (p=0.01) and DMA (p=0.05).

Plakophilin-2 is required for transcription of genes that control calcium cycling and cardiac rhythm.

Plakophilin-2 (PKP2) is a component of the desmosome and known for its role in cell-cell adhesion. Mutations in human PKP2 associate with a life-threatening arrhythmogenic cardiomyopathy, often of right ventricular predominance. Here, we use a range of state-of-the-art methods and a cardiomyocyte-specific, tamoxifen-activated, PKP2 knockout mouse to demonstrate that in addition to its role in cell adhesion, PKP2 is necessary to maintain transcription of genes that control intracellular calcium cycling. Lack of PKP2 reduces expression of Ryr2 (coding for Ryanodine Receptor 2), Ank2 (coding for Ankyrin-B), Cacna1c (coding for CaV1.2) and Trdn (coding for triadin), and protein levels of calsequestrin-2 (Casq2). These factors combined lead to disruption of intracellular calcium homeostasis and isoproterenol-induced arrhythmias that are prevented by flecainide treatment. We propose a previously unrecognized arrhythmogenic mechanism related to PKP2 expression and suggest that mutations in PKP2 in humans may cause life-threatening arrhythmias even in the absence of structural disease.It is believed that mutations in desmosomal adhesion complex protein plakophilin 2 (PKP2) cause arrhythmia due to loss of cell-cell communication. Here the authors show that PKP2 controls the expression of proteins involved in calcium cycling in adult mouse hearts, and that lack of PKP2 can cause arrhythmia in a structurally normal heart.

A Participatory Action Research Intervention in a Rural Community of Mexico Concerns Report Method

For several decades, community interventions have promoted community development with strategies involving capacity building, advocacy, social change, and empowerment. Although community interventions intend to ameliorate social and economic inequalities, there is still a need to evaluate the outcomes of Participatory Action Research (PAR). PAR approaches have demonstrated to be a helpful tool to address and identify community issues and strengths and lead community members into action. The PAR approach described in this case study of "Juanacatlan Renace" (Juanacatlan Reborn)-the Concerns Report Method (CRM)-provided a process for the community to come together and identify main issues, organize, and take actions. The findings suggest multiple activities and outcomes in areas like environmental contamination, social services, and education. Participatory methodologies like the Concerns report Method provided opportunities to community members to become engaged in pursing issues and address their own needs. The implications for community psychology research and practice are discussed.

A Participatory Action Research Method in a Rural Community of Mexico / Una investigación acción participativa en una comunidad rural de México

For several decades, community interventions have promoted community development with strategies involving capacity building, advocacy, social change, and empowerment. Although community interventions intend to ameliorate social and economic inequalities, there is still a need to evaluate the outcomes of Participatory Action Research (PAR). PAR approaches have demonstrated to be a helpful tool for addressing and identifying community issues and strengths, while leading community members into action. The PAR approach described in this case study of Ciudad Renace (Town Reborn)-the Concerns Report Method (CRM)-provided a process for the community to come together and identify main issues, organize, and take actions. The findings suggest multiple activities and outcomes in areas like environmental contamination, social services, and education. Participatory methodologies like the Concerns report Method provided opportunities for community members to become engaged in pursing issues and addressing their own needs. The implications for community psychology research and practice are discussed.

Por varias décadas, las intervenciones comunitarias han promovido el desarrollo comunitario con estrategias que implican creación de capacidades, promoción, cambio social y empoderamiento. Aunque las intervenciones comunitarias tienen la intención de mejorar las desigualdades sociales y económicas, todavía hay una necesidad de evaluar los resultados de la Investigación Acción Participativa (IAP). Los enfoques IAP han demostrado ser una herramienta útil para el direccionamiento y la identificación de problemas y fortalezas de la comunidad, al mismo tiempo que alientan a los miembros de la comunidad a la acción. El enfoque IAP descrito en este estudio de caso sobre la Ciudad Renace con el Concerns Report Method (CRM) provee de un proceso que permite a la comunidad llegar a identificar en conjunto, sus principales problemas, organizarse y tomar acciones. Los hallazgos sugieren múltiples actividades y resultados en áreas como la contaminación ambiental, los servicios sociales y la educación. Las metodologias participativas como el CRM brindan oportunidades a los miembros de la comunidad para que se involucren en la búsqueda de sus propios problemas y hacer frente a sus necesidades. Se discuten las implicancias para la investigación y la práctica de la psicología comunitaria.

Edema pulmonar por presión negativa / Negative pressure pulmonary edema

El edema pulmonar por presión negativa representa el 0.1% de las complicaciones pulmonares de los pacientes post ­ quirúrgicos, y la condicionante del incremento de dicha incidencia es la existencia de algún tipo de obstrucción de la vía aérea llegando hasta un 11% de casos. Su incidencia y prevalencia no son claras ya que es una entidad con infradiagnóstico. En los reportes de casos se coincide que la mayoría de pacientes son jóvenes con evaluaciones de riesgo quirúrgico bajos previamente sanos y que desarrollan en forma súbita un cuadro de edema agudo de pulmón, casi siempre posterior a la anesthesia, encontrándose ya no orointubados...(AU)

Edema pulmonar por presión negativa. Reporte de caso / Pulmonary edema by negative pressure. Case report

El edema pulmonar por presión negativa representa el 0.1% de las complicaciones pulmonares de los pacientes post ­ quirúrgicos, y la condicionante del incremento de dicha incidencia es la existencia de algún tipo de obstrucción de la vía aérea llegando hasta un 11% de casos. Su incidencia y prevalencia no son claras ya que es una entidad con infradiagnóstico. En los reportes de casos se coincide que la mayoría de pacientes son jóvenes con evaluaciones de riesgo quirúrgico bajos previamente sanos y que desarrollan en forma súbita un cuadro de edema agudo de pulmón, casi siempre posterior a la anesthesia, encontrándose ya no orointubados. La intensa presión negativa intrapleural secundaria al esfuerzo inspiratorio genera en el intersticio pulmonar pericapilar el gradiente transmural suficiente para producir edema. La hipoxemia, hipercapnia, acidosis e hipersecreción adrenérgica se suman al escenario, determinando las características fisiopatológicas, clínicas, radiológicas y evolutivas de esta entidad.3-4. El edema pulmonar resultante puede aparecer en pocos minutos tras la obstrucción de la vía aérea o de forma diferida al cabo de varias horas. Este cuadro clínico es potencialmente grave, pero habitualmente responde bien al tratamiento con oxigenoterapia, en raros casos es necesaria la ventilación mecánica a presión positiva y diuréticos...(AU)

Pulmonary edema by negative pressure represents 0.1% of pulmonary complications in post - surgical patients, and the condition of the increase in this incidence is the existence of some type of airway obstruction reaching up to 11% of cases. Its incidence and prevalence are not clear since it is an entity with underdiagnosis. In the case reports it is agreed that the majority of patients are young with previously low risk surgical evaluations who develop suddenly a picture of acute pulmonary edema, almost always after anesthesia, and are no longer orointubed. The intense negative intrapleural pressure secondary to the inspiratory effort generates in the pericapillary pulmonary interstice the transmural gradient sufficient to produce edema. Hypoxaemia, hypercapnia, acidosis and adrenergic hypersecretion are added to the scenario, determining the physiopathological, clinical, radiological and evolutionary characteristics of this entity.3-4. The resulting pulmonary edema may appear within a few minutes after the obstruction of the airway or deferred after several hours. This clinical picture is potentially serious, but usually responds well to treatment with oxygen therapy, in rare cases it is necessary mechanical ventilation at positive pressure and diuretics ... (AU)  

Pandemic H1N1 influenza-associated hospitalizations in children in Madrid, Spain.

OBJECTIVE: To describe the epidemiological and clinical characteristics of children hospitalized with 2009 pandemic influenza (pH1N1) in Madrid, Spain. PATIENTS/METHODS: We included patients less than 14 years of age admitted to one of 18 hospitals in Madrid, Spain, between May 1 and November 30, 2009 and diagnosed with pH1N1 by polymerase chain reaction. A retrospective chart review was conducted and data were compared by age, presence of high-risk medical conditions, and pediatric intensive care unit (PICU) admission. RESULTS: A total of 517 pH1N1 cases were included for final analysis. One hundred and forty-two patients (27·5%) had predisposing underlying illnesses, with immunosuppression (36 children, 7%) and moderate persistent asthma (34, 6·6%) being the most common ones. Patients with underlying medical conditions had longer hospital stays [median 5, interquartile range (IQR) 3-8 days, versus median 4, IQR 3-6, P < 0·001] and required intensive care (20·4% versus 5·9%, P < 0·001) and mechanical ventilation more frequently than previously healthy children. Globally, intensive care was required for 51 patients (10%) and invasive mechanical ventilation for 12 (2%). Pediatric intensive care unit admission was significantly associated with abnormal initial chest X-ray [Odds Ratio (OR) 3·5, 95% confidence interval (CI) 1·5-8·5], underlying neurological condition (OR 3·1, CI 1·2-7·5) and immunosuppression (OR 2·9, 1·2-6·8). Five patients (0·9%) died; two with severe neurological disease, two with leukemia, and one with a malignant solid tumor. CONCLUSIONS: Children with underlying medical conditions experienced more severe pH1N1 disease. Risk factors for admission to the PICU included underlying neurological conditions, immunosuppression and abnormal initial chest X-ray.