Martini 3 Coarse-Grained Model for the Cofactors Involved in Photosynthesis.

As a critical step in advancing the simulation of photosynthetic complexes, we present the Martini 3 coarse-grained (CG) models of key cofactors associated with light harvesting (LHCII) proteins and the photosystem II (PSII) core complex. Our work focuses on the parametrization of beta-carotene, plastoquinone/quinol, violaxanthin, lutein, neoxanthin, chlorophyll A, chlorophyll B, and heme. We derived the CG parameters to match the all-atom reference simulations, while structural and thermodynamic properties of the cofactors were compared to experimental values when available. To further assess the reliability of the parameterization, we tested the behavior of these cofactors within their physiological environments, specifically in a lipid bilayer and bound to photosynthetic complexes. The results demonstrate that our CG models maintain the essential features required for realistic simulations. This work lays the groundwork for detailed simulations of the PSII-LHCII super-complex, providing a robust parameter set for future studies.

pH-Dependent Conformational Switch Impacts Stability of the PsbS Dimer.

The photosystem II PsbS protein triggers the photoprotective mechanism of plants by sensing the acidification of the thylakoid lumen. Despite the mechanism of action of PsbS would require a pH-dependent monomerization of the dimeric form, a clear connection between the pH-induced structural changes and the dimer stability is missing. Here, by applying constant pH coarse-grained and all-atom molecular dynamics simulations, we investigate the pH-dependent structural response of the PsbS dimer. We find that the pH variation leads to structural changes in the lumen-exposed helices, located at the dimeric interface, providing an effective switch between PsbS inactive and active form. Moreover, the monomerization free energies reveal that in the neutral pH conformation, where the network of H-bond interactions at the dimeric interface is destroyed, the protein-protein interaction is weaker. Our results show how the pH-dependent conformations of PsbS affect their dimerization propensity, which is at the basis of the photoprotective mechanism.

Unlocking Andean sigmodontine diversity: five new species of Chilomys (Rodentia: Cricetidae) from the montane forests of Ecuador.

The Andean cloud forests of Ecuador are home to several endemic mammals. Members of the Thomasomyini rodents are well represented in the Andes, with Thomasomys being the largest genus (47 species) of the subfamily Sigmodontinae. Within this tribe, however, there are genera that have escaped a taxonomic revision, and Chilomys Thomas, 1897, constitutes a paradigmatic example of these "forgotten" Andean cricetids. Described more than a century ago, current knowledge of this externally unmistakable montane rodent is very limited, and doubts persist as to whether or not it is monotypic. After several years of field efforts in Ecuador, a considerable quantity of specimens of Chilomys were collected from various localities representing both Andean chains. Based on an extensive genetic survey of the obtained material, we can demonstrate that what is currently treated as C. instans in Ecuador is a complex comprising at least five new species which are described in this paper. In addition, based on these noteworthy new evidence, we amend the generic diagnosis in detail, adding several key craniodental traits such as incisor procumbency and microdonty. These results indicate that Chilomys probably has a hidden additional diversity in large parts of the Colombian and Peruvian territories, inviting a necessary revision of the entire genus.

Follow-up to the baby friendly hospital initiative in two hospitals of the Mexican Social Security Institute / Seguimiento de la iniciativa hospital amigo del niño y la niña en dos hospitales del Instituto Mexicano del Seguro Social

Abstract Background: The Baby Friendly Hospital Initiative has proven to be effective to increase exclusive and prolonged breastfeeding. Material and methods: Longitudinal study, in two hospitals of second level, in the period from 2015 to 2018. A percentage above 85% in each step was considered acceptable. The statistical analysis was descriptive using student's t test to compare the mean between the two hospitals and ANOVA to compare the mean throughout time in SPSS v.25. Results: Steps 1 and 7 were different between the hospitals with p = 0.010 and p = 0.023, respectively. In the follow-up, General Zone Hospital No. 5 kept steps 1, 2, 3, 7, 8, and 9 above 85%, while those who did not were steps 4, 5, 6, and 10, p = 0.37. Steps of General Hospital No. 15 that remained over 85% were 1, 3, 7, and 9; those that oscillated over time with a <85% rating were steps 2, 4, 5, 6, 8, and 10, p = 0.003. Conclusion: Monitoring child-friendly hospitals allow us to observe areas of opportunity to strengthen training for both clinical and non-clinical staff, pregnant women, the general population, and to improve exclusive and prolonged breastfeeding.

Resumen Introducción: La Iniciativa Hospital Amigo del Niño y la Niña ha probado ser efectiva para mejorar la lactancia materna exclusiva y prolongada. Material y métodos: Estudio longitudinal, en dos hospitales de segundo nivel, en el periodo de 2015 a 2018. Un porcentaje superior al 85% en cada paso se consideró aceptable. El análisis estadístico fue descriptivo, utilizando la prueba t de Student para comparar las medias entre los dos hospitales y el análisis de la varianza para compararlas a lo largo del tiempo empleando el programa SPSS v.25. Resultados: Los pasos 1 y 7 variaron entre los hospitales (con p = 0.010 y p = 0.023, respectivamente). En el seguimiento, el Hospital General de Zona (HGZ) 5 mantuvo los pasos 1, 2, 3, 7, 8 y 9 por encima del 85%, y < 85% los pasos 4, 5, 6 y 10 (p = 0.37). Las medidas del HGZ 15 que se mantuvieron > 85% fueron 1, 3, 7 y 9; aquellos que oscilaron a lo largo del tiempo con una calificación < 85% fueron los pasos 2, 4, 5, 6, 8 y 10 (p = 0.003). Conclusión: Estos seguimientos permiten observar áreas de oportunidad para reforzar la capacitación al personal clínico y no clínico como a las mujeres embarazadas, a la población en general y para mejorar la lactancia materna exclusiva y prolongada.

Functionalization of silicene and silicane with benzaldehyde.

Organic functionalization of nanomaterials offers exceptional flexibility in materials design, and applications in molecular sensors and molecular electronics are expected. However, more studies should be conducted to understand the interaction between nanomaterials and organic molecules. In this work, we studied the functionalization of silicene and silicane with benzaldehyde, performing nudged elastic band calculations within density functional theory. We calculated the structural changes of the adsorption process, electronic properties of the main states, and the energetics. In silicene, the adsorption of benzaldehyde on the top site was found to be the most stable, with an adsorption energy of -0.55 eV. For silicane, the functionalization proceeds through a self-propagating reaction on a highly reactive dangling bond generated by a hydrogen atom vacancy. Benzaldehyde adsorbed on this site depicts an adsorption energy of -1.39 eV, which is larger than in bare silicene. Upon attaching, the double C=O bond breaks down turning the molecule into a highly reactive radical, which in this case, abstracts a neighboring H atom of the sheet. This process is highly achievable since the energy barrier to abstract the H atoms is 0.81 eV, whereas the one needed to desorb the molecule is 1.39 eV. After H abstraction, a new dangling bond is generated at the substrate, making a chain reaction possible to potentially form benzaldehyde monolayers. Organic functionalization is an excellent tool to engineer properties of 2D systems, and having a deeper understanding of the adsorption processes is the first step toward the development of new generation devices. Graphical abstract Benzaldehyde adsorbed on silicene and silicane.

The Relationship Between Body Mass Index and Sexual Function in Endometrial Cancer
.

OBJECTIVES: To explore the association between pretreatment body mass index (BMI) and post-treatment sexual function in women treated for endometrial cancer. 
. SAMPLE & SETTING: 28 postmenopausal women treated with vaginal brachytherapy (VBT) took part in this multisite exploratory secondary analysis at the University of Pennsylvania and Northwestern University. 
. METHODS & VARIABLES: Secondary data analysis was used to determine if pretreatment BMI is associated with post-VBT sexual function in postmenopausal women treated for endometrial cancer at baseline and at six months post-treatment. Because of small sample size, participants were dichotomized according to enrollment BMI. RESULTS: Both groups had poor sexual function at baseline. Although improved function was observed with time, neither group reached a score indicating healthy sexual function.
. IMPLICATIONS FOR NURSING: Understanding factors that influence sexual health in patients with gynecologic cancer can improve post-treatment quality of life. 
.

Two-dimensional echo Doppler findings in juvenile and adult onset ankylosing spondylitis with long-term disease.

The authors' objective was to determine by 2-dimensional echo Doppler (2DECHO) the cardiac abnormalities in juvenile onset ankylosing spondylitis (JOAS) and adult onset ankylosing spondylitis (AOAS) in male patients with long-term disease. Twenty patients with JOAS, 31 with AOAS, and 20 healthy controls of the same age and gender without cardiopulmonary symptoms were studied. Using 2DECHO, the heart dimensions were determined according to American Society of Echocardiography guidelines. The left ventricle ejection fraction (LVEF) was calculated by Teichholz's formula. Cardiomyopathy was established when 2DECHO had diminished LVEF. Statistics used were the Student t and Fisher test, chi2, and ANOVA. Ninety percent of JOAS and 51% of AOAS patients were B27+ (p=0.005). The disease duration was 19.3 +/- 8.8 years in JOAS and 14.8 +/- 12.8 years in AOAS (p=NS). Age at the time of the study was 30.7 +/- 9.9 years in JOAS vs 40.3 +/- 12.7 in AOAS (p=0.003), and vs 40.2 +/- 17 years in controls (p=NS). There was a higher frequency of cardiomyopathy in AOAS (32.2%) than in JOAS (25%) and the controls (0%) (p=0.01). Patients with JOAS had a higher mitral valve gradient (25%) than AOAS patients (19%, p=NS) and controls (0%, p=0.04). Abnormal aortic ring reflectance was shown in 19% of AOAS vs 0% abnormalities in JOAS and controls (p=0.01). The aortic root diameter was increased in 58% of AOAS, 30% of JOAS, and 0% of controls (p=0.001). The frequency of 2DECHO abnormalities was increased in cardiopulmonary asymptomatic spondylitis patients. Despite the high frequency of B27+, JOAS had a lower frequency of aortic abnormalities than AOAS. Mitral valve gradient was found in JOAS and in AOAS that could contribute to a decreased ejection fraction and to left ventricular dysfunction.

Infarto del miocardio provocado por ingesta de bebida fría inmediatamente después de ejercicio físico intenso / Myocardial infarction after ingestion of cold beverage and strenous physical exercise

Se describe el caso de un paciente del sexo masculino de 36 años de edad, con sólo sexo masculino como factor mayor de riesgo coronario, quien presentó infarto agudo del miocardio asociado a ingestión de bebida fría inmediatamente después de ejercicio físico intenso. El estudio coronariográfico postinfarto mostró una lesión mínima de la DA. Se concluye que el espasmo coronario más ateroesclerosis es la causa más probable del infarto del miocardio en este caso. Se hace una revisión de la literatura sobre el tema.

Visceral adipose tissue is an independent correlate of glucose disposal in older obese postmenopausal women.

Older obese postmenopausal women have an increased risk for type 2 diabetes and cardiovascular disease. Increased abdominal obesity may contribute to these comorbidities. There is considerable controversy, however, regarding the effects of visceral adipose tissue as a singular predictor of insulin resistance compared to the other constituents of adiposity. To address this issue, we examined the independent association of regional adiposity and total fat mass with glucose disposal in obese older postmenopausal women. A secondary objective examined the association between glucose disposal with markers of skeletal muscle fat content (muscle attenuation) and physical activity levels. We studied 44 healthy obese postmenopausal women between 50 and 71 yr of age (mean +/- SD, 56.5 +/- 5.3 yr). The rate of glucose disposal was measured using the euglycemic/hyperinsulinemic clamp technique. Visceral and sc adipose tissue areas and midthigh muscle attenuation were measured from computed tomography. Fat mass and lean body mass were estimated from dual energy x-ray absorptiometry. Peak VO2 was measured from a treadmill test to volitional fatigue. Physical activity energy expenditure was measured from indirect calorimetry and doubly labeled water. Pearson correlations indicated that glucose disposal was inversely related to visceral adipose tissue area (r = -0.40; P < 0.01), but not to sc adipose tissue area (r = 0.17), total fat mass (r = 0.05), midthigh muscle attenuation (r = 0.01), peak VO2 (r = -0.22), or physical activity energy expenditure (r = -0.01). The significant association persisted after adjusting visceral adipose tissue for fat mass and abdominal sc adipose tissue levels (r = -0.45; P < 0.005; in both cases). Additional analyses matched two groups of women for fat mass, but with different visceral adipose tissue levels. Results showed that obese women with high visceral adipose tissue levels (283 +/- 59 vs. 137 +/- 24 cm2; P < 0.0001) had a lower glucose disposal per kg lean body mass compared to those with low visceral adipose tissue levels (0.44 +/- 0.14 vs. 0.66 +/- 0.28 mmol/kg x min; P < 0.05). Visceral adipose tissue is an important and independent predictor of glucose disposal, whereas markers of skeletal muscle fat content or physical activity exhibit little association in obese postmenopausal women.

[Myocardial infarction caused by cold beverage drinking after strenuous physical exercise]. / Infarto del miocardio provocado por ingesta de bebida fría inmediatamente después de ejercicio físico intenso.

A case of acute myocardial infarction in a 36 years old patient is presented. Maleness was male, as the only mayor coronary risk factor. He had myocardial infarction associated with ingestion of cold beverage after strenuous physical exercise. A coronariographic study was done postmyocardial infarction, which showed a mild obstruction of the LAD. The most likely cause of the coronary event in this case is coronary spasm and atherosclerosis. A review of the literature on this subject is made.

Type 2 diabetes: one disease, multiple cardiovascular risk factors.

Type 2 diabetes mellitus is a major independent risk factor for coronary artery disease. Atherosclerosis accounts for about 80% of all deaths from type 2 diabetes, of which roughly 75% are attributable to coronary artery disease and the remainder to cerebrovascular or peripheral vascular events [1]. The earlier onset and accelerated course of atherosclerosis in individuals with type 2 diabetes mellitus is multifactorial. Type 2 diabetes is associated with abnormalities in lipoprotein metabolism and increased propensity for oxidative damage. The hyperglycemia of patients with type 2 diabetes, in itself, may accelerate vascular damage. Type 2 diabetes is a hypercoagulable state attributable to enhanced coagulation and decreased fibrinolysis, as well as platelet hyperaggregability and endothelial dysfunction. Hypertension is common in individuals with type 2 diabetes and has a major impact in the accelerated atherosclerosis of this disease. This review provides an overview of selected aspects of these alterations.

Insulin resistance and type 2 diabetes mellitus: its relationship with the beta 3-adrenergic receptor.

The beta 3 subtype of adrenaline and noradrenaline receptors has been extensively characterized at structural and functional levels. Ligand binding and adenyl cyclase activation studies have helped to define their unique beta-adrenergic profile. Humans, other larger mammals, and rodents share most of the characteristic beta 3-adrenergic receptor properties, although obvious species-specific differences have been identified. Most studies in animal models have shown a distinct beta 3-adrenergic receptor activity that results in an increase in energy expenditure, decrease of fat mass (especially of intra-abdominal fat), and increased glucose disposal efficiency. It is of interest that mild weight increase was shown to develop in female but not male mice, in whom the beta 3-adrenergic receptor gene was disrupted. Recently, the incidence of a naturally occurring variant of the human beta 3-adrenergic receptor was shown to correlate with hereditary obesity in Pima Indians and Japanese individuals. In Western obese patients, this phenotype increased the capacity to gain weight and develop type 2 diabetes mellitus. Studies of humans with the Trp64Arg variant have shown controversial results. Many studies have failed to show any effect in heterozygous male subjects, and only modest effects in homozygous male subjects. In women, several studies have shown modest-to-significant effects regarding weight gain, intra-abdominal fat, and decreased insulin sensitivity in heterozygous and homozygous women. Other studies have failed to show any effect in heterozygous females. Disruptions in the activity of the beta 3-adrenergic receptor in the homozygous male and the heterozygous or homozygous female appear to have a profound effect in animal models, but a limited consequence in human physiology. Association with obesity or diabetes in humans is still controversial. This difference between animal and human models may be explained by the different quantity and distribution of metabolically active brown adipose tissue in the two.

Trp64Arg variant of the beta3-adrenoceptor and insulin resistance in obese postmenopausal women.

There is controversy regarding the role of the Trp64Arg variant of the beta3-adrenergic receptor (beta3AR) gene in the pathogenesis of insulin resistance. The modest effect of the variant as well as differences in study design, gender, age, and genetic background may contribute to divergent results among investigations. Insulin sensitivity (euglycemic clamp and tracers) was measured in 13 obese women (57 +/- 6 yr old) heterozygous for the beta3AR variant and in 14 women (57 +/- 4 yr old) homozygous for the normal gene. Groups were matched for age, body composition, intraabdominal fat, sc abdominal fat, physical activity level, and aerobic capacity. Exogenous glucose infusion during the clamp was significantly lower (P = 0.03) in beta3AR heterozygotes (241 +/- 135 mg/min) vs. normal homozygotes (379 +/- 172 mg/min). Basal endogenous glucose production was not different (P = 0.20) between heterozygotes (175 +/- 27 mg/min) and normal homozygotes (164 +/- 14 mg/min). Endogenous glucose production during hyperinsulinemia was also not different (P = 0.22) between heterozygotes (77 +/- 57 mg/min) and normal homozygotes (56 +/- 16 mg/min). Total glucose disposal adjusted for residual endogenous glucose production was lower (P = 0.049) for heterozygotes (320 +/- 111 mg/min) than for normal homozygotes (441 +/- 183 mg/min). Our results suggest that obese postmenopausal women who are heterozygous for the Trp64Arg variant in the beta3AR gene have greater insulin resistance than age-, body composition-, and physical activity-matched women homozygous for the normal gene.

Enfermedad renal poliquística / Polycystic kidney disease

La enfermedad renal poliquística es un padecimiento de causa desconocida que se ha relacionado con transmisión autosómica dominante en 30 por ciento de los pacientes. Se caracteriza por múltiples quistes distribuidos en la médula y en la corteza renal. Entre las manifestaciones clínicas hay dolor en ambos flancos, hematuria macro y microscópica, infecciones de las vías urinarias de repetición y proteinuria. A nivel extrarrenal se encuentran quistes en varios órganos. Entre 18 y 27 por ciento de los pacientes sufren alteraciones cardiovasculares, como prolapso de la válvula mitral, insuficiencias valvulares, hipertrofia del septum y del ventrículo izquierdo. Se recomienda la realización de ecocardiograma en los pacientes con sospecha de estas anormalidades. En el tratamiento es necesaria la educación de pacientes y familiares, el tratamiento de procesos infecciosos relacionados y el control adecuado de la presión arterial. El trasplante renal ha resultado tan efectivo como en aquellos pacientes en los que se ha realizado secundario a otra enfermedad renal

Lipolysis in elderly postmenopausal women.

The rate of fat oxidation at rest decreases with age in women. The mechanisms for this decrease are not clear. Theoretically, a decrease in the availability of fatty acids could explain the decline in fat oxidation. In consequence, the in vivo rate of production of fatty acids as a proxy for lipolysis was measured in 21 healthy women. Eleven of the volunteers were elderly (> 65 years) and 10 were young (< 24 years), and all were characterized for body composition. The nonadjusted rate of delivery of fatty acids into the systemic circulation was similar among elderly and young individuals (609 +/- 80.3 v 597 +/- 69.9 mumol/min, respectively, P > .1). When lipolysis was adjusted for the differences in fat-free mass using analysis of covariance (ANCOVA), rates were slightly increased in the elderly group (626 +/- 80 mumol/min) and decreased in the young group (578 +/- 84 mumol/min), but remained nonstatistically significant. It is concluded that mechanisms other than lipolysis must explain the decrease of fat oxidation in aging women, i.e., a decrease in the capacity of muscle to oxidize fat and/or a decrease in its capacity for transport of long-chain fatty acids.

Papel de la ecocardiografía transtorácica en el manejo multidisciplinario del embolislmo sistémico / Role of the transthoracic echocardiography in the multidisciplinary management of systemic embolism

Se presenta la experiencia del Servicio de Cardiología del Hospital de Especialidades ®Bernardo Sepúlveda¼ y se revisa la literatura internacional con respecto a la utilidad del estudio ecocardiográfico transtorácico en el manejo multidisciplinario de la embolia sistémica. Se analizan en forma suscinta los resultados obtenidos mediante el uso de este método diagnóstico en 38 pacientes y se analizan los resultados obtenidos mediante el uso de este método diagnóstico en 38 pacientes y se analizan los resultados obtenidos en diferentes centros ecocardiográficos internacionales y del país. Se concluye que el método ecocardiográfico transtorácico es el primer paso obligado en el estudio de pacientes en quienes se sospecha embolia arterial de orgien central tanto con fines diagnósticos como una herramienta para indicar tratamiento médico o quirúrgico en estos casos e incluso como guía en la evolución de estos pacientes

Utilidad de la ecocardiografía transtorácica en la embolia sistémica / Usefulness of transthoracic echocardiography in systemic embolism

Se presenta la experiencia del Departamento de Cardiología del Hospital de Especialidades "Bernardo Sepúlveda", Centro Médico Nacional Siglo XXI, y se revisa la literatura internacional con respecto a la utilidad del estudio ecocardiográfico transtorácico en la embolia sistémica. Se analizan en forma suscinta los resultados obtenidos mediante el uso de este método diagnóstico en 38 pacientes y los obtenidos en diferentes centros ecocardiográficos internacionales y del oaís. Se concluye que el método ecocardiográfico transtorácio es el primer paso obligado en el estudio de pacientes en quienes se sospecha embolia arterial de origen central, a pesar de que actualmente se cuenta con la ecocardiografía transesofágica; este último método debe ser usado en caso de que el estudio transtorácico sea negativo, dudoso de calidad inadecuada para el diagnóstico, o bien, que no pueda llevarse a cabo por condiciones desfavorables del paciente

Torsade de pointes en mixedema. Informe de un caso y revisión de la literatura / Torsade de pointes in myxedema. Report of a case and review of the literature

Se informa el caso de una mujer de 57 años de edad en quien se documentaron episodios de taquicardia ventricular incluyendo un episodio de torsade de pointes. La paciente era portadora de hipotiroidismo con mixedema secundario a Síndrome de Sheehan. Con el tratamiento sustitutivo de hormonas tiroideas no se presentó recurrencia de la arritmia y no hubo necesidad de administrar tratamiento antiarrítmico específico.

[Torsade de pointes in myxedema. Report of a case and review of the literature]. / Torsade de pointes en mixedema. Informe de un caso y revisión de la literatura.

A 57 years old female suffered from recurrent attacks of ventricular tachycardia including one episode of torsade de pointes, she had hypothyroidism with myxedema secondary to Sheehan Syndrome, following thyroid replacement therapy the tachyarrhythmia did not relapse and there was no need to give specific antiarrhythmic therapy.

Embolia arterial. Detección de fuente embolígena central mediante ecocardiografía transtorácica: estudio de 38 casos / Arterial embolism. detection of cardiac source of emboli by means of transthoracic echocardiogram

Se estudiaron en forma prospectiva 38 casos de pacientes con embolia sistémica con el objeto de determinar la existencia de una fuente embolígena central. Se excluyeron pacientes con sintomatología neurológica previa y con historia de claudicación intermitentes. Se incluyeron en el estudio sólo pacientes con ecocardiogramas de calidad adecuada para diagnóstico. Como objetivo secundario se valoró la utilidad del estudio como guía para indicar tratamiento médico o quirúrgico en estos casos, para evitar recidivas del fenómeno embólico. Se encontraron fuentes embolígenas centrales en 9 casos (24 por ciento): 5 con trombo en aurícula izq, 2 con trombos intraventriculares, 1 caso de mixoma en aurícula izq. y 1 caso de vegetación marántica en válvula mitral. En 2 casos, se resecó la masa intracardíaca responsable y 4 pacientes se sometieron a corrección de causa predisponente (3 casos de lesión mitral y 1 caso con aneurisma ventricular). Se concluye que la ecocardiografía transtóracica es un método de gran utilidad tanto para la detección de fuentes embolígenas centrales para el manejo racional de estos casos, aunque en la actualidad se utiliza el eco transesofágico