The 18S rRNA Methyltransferase DIMT-1 Regulates Lifespan in the Germline Later in Life.

Ribosome heterogeneity has emerged as an important regulatory control feature for determining which proteins are synthesized, however, the influence of age on ribosome heterogeneity is not fully understood. Whether mRNA transcripts are selectively translated in young versus old cells and whether dysregulation of this process drives organismal aging is unknown. Here we examined the role of ribosomal RNA (rRNA) methylation in maintaining appropriate translation as organisms age. In a directed RNAi screen, we identified the 18S rRNA N6'-dimethyl adenosine (m 6,2 A) methyltransferase, dimt-1, as a regulator of C. elegans lifespan and stress resistance. Lifespan extension induced by dimt-1 deficiency required a functional germline and was dependent on the known regulator of protein translation, the Rag GTPase, raga- 1, which links amino acid sensing to the mechanistic target of rapamycin complex (mTORC)1. Using an auxin-inducible degron tagged version of dimt-1, we demonstrate that DIMT-1 functions in the germline after mid-life to regulate lifespan. We further found that knock-down of dimt-1 leads to selective translation of transcripts important for stress resistance and lifespan regulation in the C. elegans germline in mid-life including the cytochrome P450 daf-9, which synthesizes a steroid that signals from the germline to the soma to regulate lifespan. We found that dimt-1 induced lifespan extension was dependent on the daf-9 signaling pathway. This finding reveals a new layer of proteome dysfunction, beyond protein synthesis and degradation, as an important regulator of aging. Our findings highlight a new role for ribosome heterogeneity, and specific rRNA modifications, in maintaining appropriate translation later in life to promote healthy aging.

Chatbot for communicating with university students in emergency situation.

Chatbots have arrived in higher education, and professors are trying to make the most of them. Typically, chatbots are used to help students learn academic subjects. In times of crisis, such as the COVID-19 pandemic, students who were not living with their families during the course, especially international students, were isolated and in critical situations. The student services offices were in constant contact with these students to solve problems, advise them and support them during their stay, within the constraints of confinement and the guidelines dictated by the country at the time. The student services offices were overwhelmed trying to help these students because, although the students' problems were very recurrent, the government guidelines changed from one day to the next. This article proposes the use of a chatbot to provide initial support to students during crisis situations, and facilitate communication between them and the university. The chatbot was tested by more than 160 students and student services staff. The findings support the use of chatbots as a potential tool to facilitate communication with students in emerging emergency situations, and encourage universities to adopt these types of smart tools to be prepared to respond quickly and efficiently to students in times of crisis.

Soil microbiome dataset from Guanica dry forest in Puerto Rico generated by shotgun sequencing.

Guanica dry forest (GDF), located in the southwest area or region of Puerto Rico, is among the most preserved subtropical dry forests in the world [1]. To describe the taxonomic diversity and functional profiles of this environment, metagenomic DNA was extracted from a metagenomic library generated from the GDF. The DNA was shotgun-sequenced using Illumina and analyzed using the MG-RAST server. The diversity profile revealed that the most abundant domain was Bacteria (97.8%) followed by Archaea (1.12%), Eukaryota (1.02%) and Viruses (0.03%). Out of the 50 phyla present, the most abundant was Proteobacteria (41.6%) followed by Actinobacteria (18.7%) and Acidobacteria (7.06%). Moreover, a total of 213 orders, 384 families and 791 genus were identified. The functional profile showed abundance of genes related to Carbohydrates (13.16%), Clustering-based subsystems (13.0%), Amino Acids and Derivatives (9.9%) and Protein Metabolism (8.24%). Furthermore, more specific grouping showed that NULL (21.5%) was the most abundant function group, followed by Plant-Prokaryote DOE project (6.05%), Protein biosynthesis (4.82%), Central carbohydrate metabolism (3.98%), DNA repair (2.72%) and Resistance to antibiotics and toxic compounds (2.66%). This dataset is useful in bioprospecting studies with application in biomedical sciences, biotechnology and microbial, population and applied ecology fields.

Antihyperalgesic Effects of Indomethacin, Ketorolac, and Metamizole in Rats: Effects of Metformin.

Preclinical Research Metformin-dependent mechanisms have been implicated in the antinociceptive effect of some non-steroidal anti-inflammatory drugs (NSAIDs). In this study, the effect of local peripheral or systemic administration of metformin on the local peripheral or systemic antinociception induced by indomethacin, ketorolac and metamizole was assessed in the rat carrageenan-induced thermal hyperalgesia model. Rats were injected with carrageenan (1%, 50 µl) into the right hindpaw which reduced paw withdrawal latency, a measure of thermal hyperalgesia. Local peripheral or systemic administration of indomethacin, ketorolac or metamizole dose-dependently reduced carrageenan-induced thermal hyperalgesia. Local peripheral pre-treatment with metformin (800 µg/paw) partially inhibited the anti-hyperalgesic effect of indomethacin (200 µg/paw) and metamizole (200 µg/paw), but not that of ketorolac (200 µg/paw). In contrast, systemic pre-treatment with metformin (200 mg/kg) attenuated the antihyperalgesic effect of metamizole (10 mg/kg), but not that observed with either indomethacin (10 mg/kg) or ketorolac (10 mg/kg). These findings suggest that some but not all NSAIDs have effects mediated by metformin-dependent mechanisms. Drug Dev Res 78 : 98-104, 2017. ©2017 Wiley Periodicals, Inc.

Ganglio centinela en cáncer de la cavidad oral / Sentinel node in oral-cavity cancer

Introducción: el cáncer de la cavidad oral es una localización oncológica relativamente rara, siendo el carcinoma escamocelular el tipo histológico más frecuente. El tamaño del tumor primario y la extensión a ganglios regionales han sido clásicamente los factores pronósticos más importantes. El manejo terapéutico de los ganglios regionales clínicamente negativos ha sido una disección ganglionar electiva según el riesgo de enfermedad ganglionar cervical. La utilización de la biopsia del ganglio centinela (BGC) ha aparecido como una alternativa para indicar una disección ganglionar complementaria solamente en caso de positividad de dicho ganglio. Materiales y métodos: revisamos retrospectivamente 10 casos de carcinoma escamocelular, T1 a T3, tratados inicial y simultáneamente mediante cirugía tanto del tumor primario como de los ganglios regionales. Uno o más ganglios centinelas fueron extirpados luego de inyectar azul patente en 10 casos y además, tecnecio en 8. Una disección supraomohioidea complementaria (DSOHC) fue realizada en 8 de los 10 pacientes. Resultados: el nivel IIA fue aquel en el que se encontró más frecuentemente el ganglio centinela. Hubo un falso negativo. Se obtuvo control regional de la enfermedad en 8 de los 10 pacientes (80%) pero 2 sucumbieron con enfermedad regional: una con BGC pN+ y DSOHC pN+ y otra con BGC pN- y DSOHC no realizada. Conclusiones: en el presente estudio hemos revisado nuestra experiencia inicial en el uso de la BGC en cáncer de la cavidad oral, especialmente, los aspectos técnicos de la BGC en el cuello que anatómicamente es más compleja que en otras áreas ganglionares. Debería realizarse una BGC y DSOH de manera sistemática en tumores T1 y T1 de lengua y piso de boca y optativamente para lesiones más avanzadas para mejorar la curva de aprendizaje hasta que ensayos internacionales recomienden la realización confiable de una DSOH solo en casos de BGC positiva.

Introduction: oral cavity neoplasia is rare with squamous cell carcinoma being one of the most common histological type. The most important prognostic factors are size of the primary tumor and lymph node invasion. Elective neck dissection has been considered only in cases with clinically negative neck nodes, according to risk factors for neck disease. Sentinel node biopsy (SNB) has appeared to be an alternative to complementary neck dissection, only in cases of positive SNB. Materials and methods: the clinical records of 10 patients with T1 to T3 squamous cell carcinomas were reviewed retrospectively. Al of them underwent surgical treatment of the primary lesion and neck lymph nodes at the same time. Patent blue was used to identify the sentinel node in the neck in 10 cases and technetium-99 colloid in 8. A supraomohyoid neck dissection (SOHND) was performed in 8 of the 10 patients. Results: most sentinel nodes were found at level IIA. There was one false negative result. Regional control was obtained in 8 of the patients (80%) but 2 patients died with regional disease: one with a pN+ SNB and SOHND and another with pN- SNB without SOHND. Conclusions: we have reviewed our initial experience on SNB in cancer of the oral cavity, and particularly technical aspects of the SNB in the neck, a well-known more complex anatomical region. SNB should be performed systematically in T1 and T2 lesions of the tongue and foor of the mouth and eventually, for more advanced tumors in order to improve the learning curve until international trials results recommend a complementary neck dissection only in case of positive SNB.

Manifestaciones clínicas cutáneas en pacientes con diabetes mellitus en el Hospital Nacional Dos de Mayo. Enero a diciembre del 2012 / Cutaneous clinical manifestations in patients with diabetes mellitus at the National Hospital Dos de Mayo. January to December 2012

Objetivos: Determinar las manifestaciones clínicas cutáneas en pacientes con diabetes mellitus tipo II atendidos en el servicio de Medicina Interna del Hospital Nacional Dos de Mayo. Material y métodos: El presente estudio se realizó en el servicio de medicina interna del Hospital Nacional Dos de Mayo en el periodo comprendido enero a diciembre del 2012. El estudio fue de tipo descriptivo, prospectivo, transversal. Para este estudio, el tamaño de la muestra quedó conformado por 178 casos de pacientes con diagnóstico de diabetes mellitus tipo 2, de los cuales, 174 presentaron alguna manifestación o lesión cutánea. Resultados: La edad promedio fue de 62 ± 8.15 años con extremos entre 36 a 85 años; donde la edad más frecuente lo conformaron los adultos mayores entre 61-90 años (62.35 por ciento). El sexo predominante fue el masculino en una relación de 1.37/1. De los 178 pacientes con diabetes Mellitus tipo 2, 174 casos presentaron alguna manifestación cutánea. Con una prevalencia de 97.75 por ciento. El tiempo de diabetes Mellitus 2 promedio fue de 6 ± 3.15 años, el tiempo de enfermedad más frecuente fue más de 5 años (60.10 por ciento). El 78.10 por ciento utiliza drogas orales hipoglicemiantes y el 21.90 por ciento insulina. La dermopatía diabética prevaleció en 84 pacientes (47.19 por ciento). Las infecciones cutáneas fúngicas prevalecieron en 119 diabéticos (66.81 por ciento), notándose una mayor presencia de pacientes con tiña unguium (26.4 por ciento); vulvovaginitis candidiásico (11.23 por ciento); intertrigo candidiásico (6.74 por ciento) y con tiña corporis (7.86 por ciento). Las manifestaciones vasculares de la diabetes Mellitus prevalecieron en 115 pacientes (64.6 por ciento); notándose con mayor presencia casos con microangiopatía funcional (47.19 por ciento), en relación a pacientes con macroangiopatías (17.41 por ciento). Las manifestaciones cutáneas de la neuropatía diabética prevalecieron en 41 casos (23.03 por ciento); notándose, que 05 casos...

Objectives: Determine clinical cutaneous manifestations in patients with type II diabetes mellitus treated at the department of Internal Medicine of the National Hospital Dos de Mayo. Material and methods: This study was conducted in the internal medicine department of Hospital Nacional Dos de Mayo in the period January to December 2012. The study was descriptive, prospective, and transversal. For this study, the size of the sample was comprised of 178 cases of patients diagnosed with type 2 diabetes mellitus, of which 174 presented any representation or skin lesion. Results: The average age was 62 ± 8.15 years with extremes from 36 to 85 years; where the most frequent age was conformed older adults between 61-90 years (62.35 per cent). The dominant males were in a ratio of 1.37/1. Of the 178 patients with diabetes mellitus type 2, 174 cases had a skin manifestation. With a prevalence of 97.75 per cent. Time average 2 diabetes mellitus was 6 ± 3.15 years, the time of most frequent disease was 5 years (60.10 per cent). The 78.10 per cent used oral hypoglycemic drugs and insulin 21.90 per cent. Diabetic dermopathy prevailed in 84 patients (47.19 per cent) Fungal skin infections prevailed in 119 diabetics (66.81 per cent) and noted an increased presence of tinea unguium patients (26.4 per cent); candidal vulvovaginitis (11.23 per cent); candidal intertrigo (6.74 per cent) and tinea corporis (7.86 per cent). Vascular manifestations of diabetes mellitus prevailed in 115 patients (64.6 per cent): noticing more microangiopathy presence practical cases (47.19 per cent) compared to patients with macroangiopathies (17.41 per cent). Cutaneous manifestations of diabetic neuropathy prevailed in 41 cases (23.03 per cent); noticing that 05 cases had diabetic foot (2.90 per cent). Prevalence of skin reactions related to the treatment of diabetes mellitus with oral hypoglycemic agents was observed in 03 cases (1.7 per cent). Conclusions: The study shows a high prevalence of...