Nitrogen loss in coastal sediments driven by anaerobic ammonium oxidation coupled to microbial reduction of Mn(IV)-oxide.

Coastal sediments play a central role in regulating the amount of land-derived reactive nitrogen (Nr) entering the ocean, and their importance becomes crucial in vulnerable ecosystems threatened by anthropogenic activities. Sedimentary denitrification has been identified as the main sink of Nr in marine environments, while anaerobic ammonium oxidation with nitrite (anammox) has also been pointed out as a key player in controlling the nitrogen pool in these locations. Collected evidence in the present work indicates that the microbial biota in coastal sediments from Baja California (northwestern Mexico) has the potential to drive anaerobic ammonium oxidation linked to Mn(IV) reduction (manganammox). Unamended sediment showed ammonification, but addition of vernadite (δMnO2 with nano-crystal size ∼15 Å) as terminal electron acceptor fueled simultaneous ammonium oxidation (up to ∼400 µM of ammonium removed) and production of Mn(II) with a ratio ∆[Mn(II)]/∆[NH4+] of 1.8, which is very close to the stoichiometric value of manganammox (1.5). Additional incubations spiked with external ammonium also showed concomitant ammonium oxidation and Mn(II) production, accounting for ∼30 % of the oxidized ammonium. Tracer analysis revealed that the nitrogen loss associated with manganammox was 4.2 ± 0.4 µg 30N2/g-day, which is 17-fold higher than that related to the feammox process (anaerobic ammonium oxidation linked to Fe(III) reduction, 0.24 ± 0.02 µg 30N2/g-day). Taxonomic characterization based on 16S rRNA gene sequencing revealed the existence of several clades belonging to Desulfobacterota as potential microorganisms catalyzing the manganammox process. These findings suggest that manganammox has the potential to be an additional Nr sink in coastal environments, whose contribution to total Nr losses remains to be evaluated.

Ammonium loss microbiologically mediated by Fe(III) and Mn(IV) reduction along a coastal lagoon system.

Anaerobic ammonium oxidation, associated with both iron (Feammox) and manganese (Mnammox) reduction, is a microbial nitrogen (N) removal mechanism recently identified in natural ecosystems. Nevertheless, the spatial distributions of these non-canonical Anammox (NC-Anammox) pathways and their environmental drivers in subtidal coastal sediments are still unknown. Here, we determined the potential NC-Anammox rates and abundance of dissimilatory metal-reducing bacteria (Acidomicrobiaceae A6 and Geobacteraceae) at different horizons (0-20 cm at 5 cm intervals) of subtidal coastal sediments using the 15N isotope-tracing technique and molecular analyses. Sediments were collected across three sectors (inlet, transition, and inner) in a coastal lagoon system (Bahia de San Quintin, Mexico) dominated by seagrass meadows. The positive relationship between 30N2 production rates and dissimilatory Fe and Mn reduction provided evidence for Feammox's and Mnammox's co-occurrence. N loss through NC-Anammox was detected in subtidal sediments, with potential rates of 0.07-0.62 µg N g-1 day-1. NC-Anammox process in vegetated sediments tended to be higher than those in adjacent unvegetated ones. NC-Anammox rates showed a subsurface peak (between 5 and 15 cm) in the vegetated sediments but decreased consistently with depth in the adjacent bare bottoms. Thus, the presence/absence of seagrasses and sediment characteristics, particularly the availability of organic carbon and microbiologically reducible Fe(III) and Mn(IV), affected the abundance of dissimilatory metal-reducing bacteria, which mediated NC-Anammox activity and the associated N removal. An annual loss of 32.31 ± 3.57 t N was estimated to be associated with Feammox and Mnammox within the investigated area, accounting for 2.8-4.7% of the gross total import of reactive N from the ocean into the Bahia de San Quintin. Taken as a whole, this study reveals the distribution patterns and controlling factors of the NC-Anammox pathways along a coastal lagoon system. It improves our understanding of the coupling between N and trace metal cycles in coastal environments.

Marine heatwaves can limit the role of surfgrasses as biofilters for wastewaters.

Marine heatwaves (MHWs) can have detrimental effects on seagrasses, but knowledge about the impacts on their ecosystem services remains scarce. This work evaluated Phyllospadix scouleri (surgrass) as a biofilter for wastewater discharges, and how warming associated with MHW may affect this ecological function. The nitrogen uptake kinetics and assimilation abilities for ammonium, nitrate, and urea were examined under two different warming scenarios (single and repeated events) simulated in a mesocosm. N-uptake kinetics were related to urban sewage discharges close to surfgrass meadows. Our results revealed that surfgrasses can serve as effective biofilters because of their high nitrogen uptake rates and above-average canopy biomass. Nonetheless, exposure to both experimental warmings resulted in a significant decline in their ability to incorporate and assimilate nitrogen. Consequently, MHWs may reduce the capacity of surfgrasses to function as nitrogen sinks and green filters for sewage waters, jeopardizing their role as Blue Nitrogen systems.

Allergen exposure boosts peripheral Th9 responses in patients with local allergic rhinitis.

KEY POINTS: Intranasal allergen exposure increases peripheral total Th2 and Th9 cells in patients with local allergic rhinitis (LAR). Peripheral T-cell response seems dominated by Th9 cells in patients with LAR, whereas Th2 responses prevail in patients with allergic rhinitis. Our results identify Th9 cells as potential therapeutic targets for patients with LAR.

Predictors of Mechanical Ventilation in Guillain-Barré Syndrome with Axonal Subtypes.

BACKGROUND: The early clinical predictors of respiratory failure in Latin Americans with Guillain-Barré syndrome (GBS) have scarcely been studied. This is of particular importance since Latin America has a high frequency of axonal GBS variants that may imply a worse prognosis. METHODS: We studied 86 Mexican patients with GBS admitted to the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, a referral center of Mexico City, to describe predictors of invasive mechanical ventilation (IMV). RESULTS: The median age was 40 years (interquartile range: 26-53.5), with 60.5% men (male-to-female ratio: 1.53). Most patients (65%) had an infectious antecedent (40.6% gastrointestinal). At admission, 38% of patients had a Medical Research Council (MRC) sum score <30. Axonal subtypes predominated (60.5%), with acute motor axonal neuropathy being the most prevalent (34.9%), followed by acute inflammatory demyelinating polyneuropathy (32.6%), acute motor sensory axonal neuropathy (AMSAN) (25.6%), and Fisher syndrome (7%). Notably, 15.1% had onset in upper limbs, 75.6% dysautonomia, and 73.3% pain. In all, 86% received either IVIg (9.3%) or plasma exchange (74.4%). IMV was required in 39.5% patients (72.7% in AMSAN). A multivariate model without including published prognostic scores yielded the time since onset to admission <15 days, axonal variants, MRC sum score <30, and bulbar weakness as independent predictors of IMV. The model including grading scales yielded lower limbs onset, Erasmus GBS respiratory insufficiency score (EGRIS) >4, and dysautonomia as predictors. CONCLUSION: These results suggest that EGRIS is a good prognosticator of IMV in GBS patients with a predominance of axonal electrophysiological subtypes, but other early clinical data should also be considered.

The Utility of Nasal Challenges to Phenotype Asthma Patients.

Asthma is a heterogeneous disease in terms of both phenotype and response to therapy. Therefore, there is a great need for clinically applicable tools allowing for improved patient classification, and selection for specific management approaches. Some interventions are highly helpful in selected patients (e.g., allergen immunotherapy or aspirin desensitization), but they are costly and/or difficult to implement. Currently available biomarkers measurable in peripheral blood or exhaled air display many limitations for asthma phenotyping and cannot identify properly the specific triggers of the disease (e.g., aeroallergens or NSAID). The united airway concept illustrates the relevant epidemiological and pathophysiological links between the upper and lower airways. This concept has been largely applied to patient management and treatment, but its diagnostic implications have been less often explored. Of note, a recent document by the European Academy of Allergy and Clinical Immunology proposes the use of nasal allergen challenge to confirm the diagnosis of allergic asthma. Similarly, the nasal challenge with lysine acetylsalicylate (L-ASA) can be used to identify aspirin-sensitive asthma patients. In this review, we will summarize the main features of allergic asthma and aspirin-exacerbated respiratory disease and will discuss the methodology of nasal allergen and L-ASA challenges with a focus on their capacity to phenotype the inflammatory disease affecting both the upper and lower airways.

Tratamiento endoscópico de fístula broncopericárdica en paciente con cáncer de pulmón / Endoscopic Treatment of Bronchopericardial Fistula in Lung Cancer Patient

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[Translated article] Endoscopic Treatment of Bronchopericardial Fistula in Lung Cancer Patient / Tratamiento endoscópico de fístula broncopericárdica en paciente con cáncer de pulmón

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Neurologic manifestations in hospitalized patients with COVID-19 in Mexico City.

BACKGROUND: The coronavirus disease 2019 (COVID-19) is a systemic entity that frequently implies neurologic features at presentation and complications during the disease course. We aimed to describe the characteristics and predictors for developing in-hospital neurologic manifestations in a large cohort of hospitalized patients with COVID-19 in Mexico City. METHODS: We analyzed records from consecutive adult patients hospitalized from March 15 to June 30, 2020, with moderate to severe COVID-19 confirmed by reverse transcription real-time polymerase chain reaction (rtRT-PCR) for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Neurologic syndromes were actively searched by a standardized structured questionnaire and physical examination, confirmed by neuroimaging, neurophysiology of laboratory analyses, as applicable. RESULTS: We studied 1,072 cases (65% men, mean age 53.2±13 years), 71 patients had pre-existing neurologic diseases (diabetic neuropathy: 17, epilepsy: 15, history of ischemic stroke: eight, migraine: six, multiple sclerosis: one, Parkinson disease: one), and 163 (15.2%) developed a new neurologic complication. Headache (41.7%), myalgia (38.5%), dysgeusia (8%), and anosmia (7%) were the most common neurologic symptoms at hospital presentation. Delirium (13.1%), objective limb weakness (5.1%), and delayed recovery of mental status after sedation withdrawal (2.5%), were the most common new neurologic syndromes. Age, headache at presentation, preexisting neurologic disease, invasive mechanical ventilation, and neutrophil/lymphocyte ratio ≥9 were independent predictors of new in-hospital neurologic complications. CONCLUSIONS: Even after excluding initial clinical features and pre-existing comorbidities, new neurologic complications in hospitalized patients with COVID-19 are frequent and can be predicted from clinical information at hospital admission.

Clinical and neurophysiological description of patients with POEMS syndrome.

INTRODUCTION: POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) is a monoclonal gammopathy with polyneuropathy as a mandatory criterion. OBJECTIVE: To describe potential associations between clinical expression and electrodiagnostic patterns in POEMS syndrome. METHOD: Observational, retrospective, cross-sectional study of cases cared for in a referral center, diagnosed with POEMS syndrome from 2009 to 2019. RESULTS: Eleven patients (8 men) were analyzed. Median age at diagnosis was 40 years (range: 31-51; mean: 37.19 ± 15.67 years). Mean latency at diagnosis was 9.7 ± 8.37 months. In all subjects, initial clinical manifestation was polyneuropathy. Most patients had an axonal pattern (n = 5), followed by demyelinating (n = 4) and mixed patterns (n = 2). Monoclonal gammopathy was observed in all (6 l and 5 k cases; immunoglobulin [Ig] G: 72 %; IgA: 18 %; IgM: 9 %). Medical Research Council sum score was lower in the axonal pattern (median: 37.00 vs. 45.5; p = 0.024). There were no differences in systemic involvement between electrophysiological patterns. CONCLUSION: Electrophysiological patterns are unlikely to have a clear extra-neurological clinical correspondence; however, this will have to be definitively proven with a larger sample size.

INTRODUCCIÓN: El síndrome POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal protein, skin changes) es una gammapatía monoclonal con polineuropatía como criterio obligatorio. OBJETIVO: Describir las potenciales asociaciones entre la expresión clínica y los patrones de electrodiagnóstico en el síndrome POEMS. MÉTODO: Estudio observacional, retrospectivo y transversal de los casos atendidos en un centro de referencia con diagnóstico de síndrome de POEMS de 2009 a 2019. RESULTADOS: Se analizó a 11 pacientes (8 hombres). La mediana de la edad al diagnóstico fue de 40 años (rango: 31-51, media: 37.19 ± 15.67 años). La latencia media al diagnóstico fue de 9.7 ± 8.37 meses. En todos la manifestación clínica inicial fue la polineuropatía. La mayoría de los pacientes presentaron un patrón axonal (n = 5), seguido del desmielinizante (n = 4) y mixto (n = 2). La gammapatía monoclonal se observó en todos (6 casos l y 5 k, inmunoglobulina [Ig] G: 72%, IgA: 18%, IgM: 9%). El Medical Research Council sum score fue menor en el patrón axonal (medianas: 37.00 vs. 45.5, p = 0.024). No se presentaron diferencias en la afección sistémica entre patrones electrofisiológicos. CONCLUSIÓN: Es poco probable que los patrones electrofisiológicos tengan una correspondencia clínica extraneurológica clara, sin embargo, esto deberá probarse de forma definitiva con un mayor tamaño de muestra.

Testosterone dependent territorial aggression is modulated by cohabitation with a female in male Mongolian gerbils (Meriones unguiculatus).

Most mammal studies on the neuroendocrine mechanisms of territorial aggression have demonstrated that testosterone (T) is required for the display of territorial aggression. However, the relationship between T and aggression is more complex and may be modulated by social factor. The aim of this study was to determine the role of T in territorial aggression in the Mongolian gerbil (Meriones unguiculatus), and the effect of social factors on the modulation of this behavior. The relationship between T and territorial aggression was analyzed using castration and T replacement in two social contexts: male-male and male-female cohabitation. Plasma T concentrations in males of all groups were quantified by radioimmunoassay (RIA). T concentrations were compared using two-way ANOVA. Only sham-castrated and castrated males with T replacement in male-female cohabitation showed aggression, whereas castrated gerbils in the same condition were not aggressive. This indicates that T is the hormone that maintains territorial aggression, but mating is a modulator stimulus. The modulator effect of mating in territorial aggression was associated with an increase in T, but it seems that other mechanisms are involved in the regulation of this behavior, since castrated males with T replacement in the male-male cohabitation did not exhibit aggression, although they had T concentrations as high as these males that received the same treatment, but that cohabited with a female. These results suggest that T is involved in the mechanisms that regulate territorial aggression in the male Mongolian gerbil, and that the cohabitation with a female modulates this behavior.

Enfermedad carotídea aterosclerosa y enfermedad de sustancia blanca en sujetos sin historia de infarto cerebral o isquemia cerebral transitoria.

INTRODUCTION: Atherosclerotic carotid artery disease (CAD) is a major risk factor for cerebrovascular disease. OBJECTIVE: To analyze the association of major vascular risk factors with atherosclerotic CAD and white matter disease (WMD) in patients without a history of ischemic stroke. METHOD: Risk factors were assessed with carotid examination using Doppler duplex ultrasound. Cases with a history cerebral infarction or transient ischemic attack were not included. Subjects had brain magnetic resonance imaging scans available and those with large-artery ischemic lesions were excluded. Multivariate models were constructed for the prediction of atherosclerotic CAD, significant carotid stenosis, atheroma burden and WMD. RESULTS: One-hundred and forty-five subjects were assessed (60.7% were females, mean age was 73 years). Atherosclerotic CAD was documented in 54.5%, carotid stenosis ≥ 50% in 9.0%, > 6 atheroma plaques in 7.6%, and periventricular or subcortical WMD in 28.3% (20.6% had atherosclerotic CAD and WMD concurrently). Risk factors independently associated with atherosclerotic CAD were age and hypertension; hypertension was associated with ≥ 50% carotid stenosis; age was associated with > 6 atheroma plaques; and age, diabetes and hypertension were associated with WMD. Obesity was not associated with any of the analyzed independent variables. CONCLUSIONS: In asymptomatic subjects without a history of ischemic stroke, age and hypertension were the most important risk factors for macrovascular disease. Diabetes mellitus was associated with microvascular disease. Obesity alone was not a major determinant of CAD or WMD.

INTRODUCCIÓN: La enfermedad carotídea aterosclerosa (ECA) es un factor de riesgo importante para enfermedad vascular cerebral. OBJETIVO: Analizar la asociación entre factores de riesgo vascular mayores con ECA y leucopatía cerebral en pacientes sin historia de ictus isquémico. MÉTODO: Se evaluaron factores de riesgo en sujetos con exploración de carótidas mediante ultrasonografía Doppler dúplex. No se incluyeron casos con historia de infarto cerebral o ataque isquémico transitorio. Los sujetos contaron con resonancia magnética cerebral y se excluyeron aquellos con lesiones isquémicas de grandes vasos. Se construyeron modelos multivariable para la predicción de ECA, estenosis carotídea significativa, carga de ateromas y leucopatía cerebral. RESULTADOS: Se estudiaron 145 sujetos (60.7 % mujeres, edad de 73 años). Se documentó ECA en 54.5 %, estenosis carotídea ≥ 50 % en 9 %, carga de placas de ateroma > 6 en 7.6 % y leucopatía periventricular o subcortical en 28.3 % (20.6 % tenían concurrentemente ECA y leucopatía). Los factores asociados independientemente con ECA fueron edad e hipertensión; con estenosis ≥ 50 %, hipertensión; con cargas de ateromas > 6 placas, edad; con leucopatía, edad, diabetes e hipertensión. La obesidad no se asoció con las variables independientes analizadas. CONCLUSIONES: En los sujetos asintomáticos sin historia de ictus isquémico, la edad y la hipertensión fueron los factores de riesgo más importantes para enfermedad macrovascular. La diabetes mellitus se asoció con enfermedad microvascular. La obesidad por sí sola no fue un determinante mayor de ECA o leucopatía cerebral.

Enfermedad carotídea aterosclerosa y enfermedad de sustancia blanca en sujetos sin historia de infarto cerebral o isquemia cerebral transitoria / Atherosclerotic Carotid Disease and White Matter Disease in Subjects Without a History of Cerebral Infarction or Transient Cerebral Ischemia

Resumen Introducción: La enfermedad carotídea aterosclerosa (ECA) es un factor de riesgo importante para enfermedad vascular cerebral. Objetivo: Analizar la asociación entre factores de riesgo vascular mayores con ECA y leucopatía cerebral en pacientes sin historia de ictus isquémico. Método: Se evaluaron factores de riesgo en sujetos con exploración de carótidas mediante ultrasonografía Doppler dúplex. No se incluyeron casos con historia de infarto cerebral o ataque isquémico transitorio. Los sujetos contaron con resonancia magnética cerebral y se excluyeron aquellos con lesiones isquémicas de grandes vasos. Se construyeron modelos multivariable para la predicción de ECA, estenosis carotídea significativa, carga de ateromas y leucopatía cerebral. Resultados: Se estudiaron 145 sujetos (60.7 % mujeres, edad de 73 años). Se documentó ECA en 54.5 %, estenosis carotídea ≥ 50 % en 9 %, carga de placas de ateroma > 6 en 7.6 % y leucopatía periventricular o subcortical en 28.3 % (20.6 % tenían concurrentemente ECA y leucopatía). Los factores asociados independientemente con ECA fueron edad e hipertensión; con estenosis ≥ 50 %, hipertensión; con cargas de ateromas > 6 placas, edad; con leucopatía, edad, diabetes e hipertensión. La obesidad no se asoció con las variables independientes analizadas. Conclusiones: En los sujetos asintomáticos sin historia de ictus isquémico, la edad y la hipertensión fueron los factores de riesgo más importantes para enfermedad macrovascular. La diabetes mellitus se asoció con enfermedad microvascular. La obesidad por sí sola no fue un determinante mayor de ECA o leucopatía cerebral.

Abstract Introduction: Atherosclerotic carotid artery disease (CAD) is a major risk factor for cerebrovascular disease. Objective: To analyze the association of major vascular risk factors with atherosclerotic CAD and white matter disease (WMD) in patients without a history of ischemic stroke. Method: Risk factors were assessed with carotid examination using Doppler duplex ultrasound. Cases with a history cerebral infarction or transient ischemic attack were not included. Subjects had brain magnetic resonance imaging scans available and those with large-artery ischemic lesions were excluded. Multivariate models were constructed for the prediction of atherosclerotic CAD, significant carotid stenosis, atheroma burden and WMD. Results: One-hundred and forty-five subjects were assessed (60.7% were females, mean age was 73 years). Atherosclerotic CAD was documented in 54.5%, carotid stenosis ≥ 50% in 9.0%, > 6 atheroma plaques in 7.6%, and periventricular or subcortical WMD in 28.3% (20.6% had atherosclerotic CAD and WMD concurrently). Risk factors independently associated with atherosclerotic CAD were age and hypertension; hypertension was associated with ≥ 50% carotid stenosis; age was associated with > 6 atheroma plaques; and age, diabetes and hypertension were associated with WMD. Obesity was not associated with any of the analyzed independent variables. Conclusions: In asymptomatic subjects without a history of ischemic stroke, age and hypertension were the most important risk factors for macrovascular disease. Diabetes mellitus was associated with microvascular disease. Obesity alone was not a major determinant of CAD or WMD.

Zwitterionic codeine-derived methacrylate monoliths for enantioselective capillary electrochromatography of chiral acids and chiral bases.

Thiol-ene click reaction of N-acetyl-L-cysteine methyl ester to codeine, followed by reaction with allyl isocyanate and hydrolysis to the corresponding zwitterionic chiral selector and its subsequent bonding to the surface of a methacrylate monolith provided a new chiral capillary column for enantiomer separation of chiral acids and chiral bases. First, the epoxy groups of a poly(glycidyl methacrylate-co-ethylene dimethacrylate) monolith were converted into amine residues, followed by reaction with allylglycidyl ether. In this way, a spacer arm was bonded to the surface before coating and cross-linking poly(3-mercaptopropyl methylsiloxane) (PMPMS) via radical addition (thiol-ene click reaction) to the surface. In order to improve the performance of the monolithic chiral stationary phase, thio ether and residual thiol groups were oxidized to sulfonyl and sulphonate groups, respectively. This novel chiral stationary phase (CSP) was evaluated by capillary electrochromatography (CEC) using two chiral model compounds, namely N-3,5-dinitrobenzoyl-R,S-leucine (retained by anion-exchange mechanism) and mefloquine (by cation-exchange process). The ion-exchange retention mechanism on the CSP was characterized for these two counterionic model solutes by varying the mobile phase composition, including the nature of solvents, the concentration of counter-ions and co-ions, and the acid-to-base ratio. A series of chiral ß-blockers and amino acid derivatives was used to further check the performance of the modified monolith under the optimal conditions. Several enantiomers were baseline resolved with reasonable peak efficiencies (up to 60,000 theoretical plates per meter for the second eluted enantiomer).

Effectiveness of Intra-Articular Injections of Sodium Hyaluronate or Corticosteroids for Intracapsular Temporomandibular Disorders: A Systematic Review and Meta-Analysis.

AIMS: To assess the effectiveness of intra-articular injections of sodium hyaluronate (NaH) or corticosteroids (CS) for treatment of intracapsular temporomandibular disorders (TMD). METHODS: Single- or double-blinded randomized controlled trials (RCTs) on the effectiveness of NaH or CS injections, compared to each other or to placebo, for the treatment of intracapsular TMD due to osteoarthritis and/or internal joint derangement were analyzed in this systematic review and meta-analysis. Electronic searches of MEDLINE through the PubMed, Web of Science, and Cochrane Library databases were conducted on March 17, 2015, and an updated search was conducted on June 7, 2017. Three reviewers independently extracted the data and assessed the risk of bias of included studies. RESULTS: An initial search yielded 245 studies, and 5 additional studies were identified through cross referencing. A total of 22 studies were identified as relevant based on the abstracts, but only 7 RCTs met the inclusion criteria. Six of the included studies had unclear risk of bias, and one had high risk of bias. Four studies were eligible for meta-analysis. Pooled results showed no significant difference in short- or long-term pain improvement with NaH compared to CS. The number of responders to NaH was significantly more than placebo in one study, but not significantly higher than CS in another study. CONCLUSION: Although there was no significant difference between the effectiveness of NaH and CS intra-articular injections, there was some evidence that NaH was better than placebo. Further research is needed to determine the minimum effective dose and long-term side effects of both injections.

Testosterone induces paternal behavior in sexually inexperienced males of Neotomodon alstoni (Rodentia: Muridae) / La testosterona induce conducta paterna en machos sin experiencia sexual del ratón Mexicano de los volcanes Neotomodon alstoni (Rodentia: Muridae)

Abstract The inhibition of infanticide can be considered a prerequisite for the onset of paternal behavior. Thus, hormones such as testosterone (T) would be expected to mediate the inhibition of aggression toward pups and the onset of paternal care. However, the effect of T in onset of this behaviorseems to depend of sexual experience. The aim of this study was to determine whether T induces paternal behavior in sexually inexperienced males of the Mexican volcano mouse (Neotomodon alstoni). For this, 33 non-paternal males were selected based on paternal behavior tests. These non-paternal mice were organized in three groups: 10 males were castrated, 10 subjected to sham procedure, and 13 underwent castration and T replacement. After of these treatments, the males were again evaluated by a second paternal behavior test, and blood samples were obtained to measure plasma T levels by radioimmunoassay. Castrated males with T replacement changed their behavior; 46.2 % of these males displayed paternal behavior despite 92.3 % of these males having previously displayed aggressive behavior in the selection test. An increase in T facilitates the onset of paternal behavior in sexually inexperienced males of Mexican volcano mouse, as occurs in sexual experience males. These results support the hypothesis that an increase in T levels would be involved in the neuroendocrine mechanisms that suppress infanticide and promote the onset of parental behavior in Mexican volcano mice males. Future studies in this mouse will investigate whether T regulates the onset of paternal behavior via conversion to estradiol or whether both T metabolites are involved in its onset.

Resumen La inhibición del infanticidio es necesaria en el inicio de la conducta paterna, así hormonas como la testosterona (T) pueden mediar la transición de machos agresivos a paternales. Sin embargo, el efecto de la T en el inicio de la conducta paterna parece depender de la experiencia sexual. El objetivo de este estudio fue determinar si T induce la conducta paterna en machos sin experiencia sexual del ratón Neotomodon alstoni. A través de pruebas de conducta paterna fueron seleccionados 33 machos no paternales; 23 fueron castrados bilateralmente, de los cuales a 13 se les colocó implante de T y 10 no recibieron ningún tratamiento. Otros 10 machos fueron sometidos a simulación del procedimiento. Después de los tratamientos, se realizaron nuevamente pruebas de conducta paterna para determinar cambios en la conducta de los machos hacia las crías. Enseguida se extrajeron muestras sanguíneas, para cuantificar los niveles de T en plasma, por radioinmuensayo. El 46.2 % de los machos castrados que recibieron implantes de T exhibieron conducta paterna, a pesar de que antes de la administración de esta hormona, el 92.3 % fueron agresivos con las crías. Los machos que transitaron a paternales tuvieron concentraciones de T significativamente más altas que los machos con castración simulada. Un incremento en T facilita el inicio de la conducta paterna en machos sexualmente inexpertos del ratón Neotomodon alstoni.Estos resultados apoyan la hipótesis que un incremento en T está involucrado en los mecanismos neuroendócrinos que inhiben la agresión hacia las crías y facilitan el inicio de la conducta paterna. Investigaciones futuras deben enfocarse a establecer la función de ambos metabolitos de la T en la regulación de la conducta paterna de este ratón.

Application of Organic Monolithic Materials to Enantioseparation in Capillary Separation Techniques.

This review article is primarily focused on the state-of-the-art of enantioseparations on organic monolithic materials. The article gives an overview of the chiral stationary phases and its application in capillary electrochromatography (CEC), and capillary- and nano-liquid chromatography (cLC and nLC). Since thousands of publications have been emerged from 2000's and citing all these papers would extend the scope of this review; then, recent developments from last 10 years (2006 to 2016) will be mentioned. Mostly, stationary phases based on copolymers obtained from chiral functional monomers and surface modifications of organic monoliths with chiral ligands will be discussed. The effective application of these chiral separation methodologies in several analysis areas will be also included.

Randomized Trial of Thymectomy in Myasthenia Gravis.

BACKGROUND: Thymectomy has been a mainstay in the treatment of myasthenia gravis, but there is no conclusive evidence of its benefit. We conducted a multicenter, randomized trial comparing thymectomy plus prednisone with prednisone alone. METHODS: We compared extended transsternal thymectomy plus alternate-day prednisone with alternate-day prednisone alone. Patients 18 to 65 years of age who had generalized nonthymomatous myasthenia gravis with a disease duration of less than 5 years were included if they had Myasthenia Gravis Foundation of America clinical class II to IV disease (on a scale from I to V, with higher classes indicating more severe disease) and elevated circulating concentrations of acetylcholine-receptor antibody. The primary outcomes were the time-weighted average Quantitative Myasthenia Gravis score (on a scale from 0 to 39, with higher scores indicating more severe disease) over a 3-year period, as assessed by means of blinded rating, and the time-weighted average required dose of prednisone over a 3-year period. RESULTS: A total of 126 patients underwent randomization between 2006 and 2012 at 36 sites. Patients who underwent thymectomy had a lower time-weighted average Quantitative Myasthenia Gravis score over a 3-year period than those who received prednisone alone (6.15 vs. 8.99, P<0.001); patients in the thymectomy group also had a lower average requirement for alternate-day prednisone (44 mg vs. 60 mg, P<0.001). Fewer patients in the thymectomy group than in the prednisone-only group required immunosuppression with azathioprine (17% vs. 48%, P<0.001) or were hospitalized for exacerbations (9% vs. 37%, P<0.001). The number of patients with treatment-associated complications did not differ significantly between groups (P=0.73), but patients in the thymectomy group had fewer treatment-associated symptoms related to immunosuppressive medications (P<0.001) and lower distress levels related to symptoms (P=0.003). CONCLUSIONS: Thymectomy improved clinical outcomes over a 3-year period in patients with nonthymomatous myasthenia gravis. (Funded by the National Institute of Neurological Disorders and Stroke and others; MGTX ClinicalTrials.gov number, NCT00294658.).