Micrococcin cysteine-to-thiazole conversion through transient interactions between the scaffolding protein TclI and the modification enzymes TclJ and TclN.

Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a broad group of compounds mediating microbial competition in nature. Azole/azoline heterocycle formation in the peptide backbone is a key step in the biosynthesis of many RiPPs. Heterocycle formation in RiPP precursors is often carried out by a scaffold protein, an ATP-dependent cyclodehydratase, and an FMN-dependent dehydrogenase. It has generally been assumed that the orchestration of these modifications is carried out by a stable complex including the scaffold, cyclodehydratase, and dehydrogenase. The antimicrobial RiPP micrococcin begins as a precursor peptide (TclE) with a 35-amino acid N-terminal leader and a 14-amino acid C-terminal core containing six Cys residues that are converted to thiazoles. The putative scaffold protein (TclI) presumably presents the TclE substrate to a cyclodehydratase (TclJ) and a dehydrogenase (TclN) to accomplish the two-step installation of the six thiazoles. In this study, we identify a minimal TclE leader region required for thiazole formation, demonstrate complex formation between TclI, TclJ, and TclN, and further define regions of these proteins required for complex formation. Our results point to a mechanism of thiazole installation in which TclI associates with the two enzymes in a mutually exclusive fashion, such that each enzyme competes for access to the peptide substrate in a dynamic equilibrium, thus ensuring complete modification of each Cys residue in the TclE core. IMPORTANCE: Thiopeptides are a family of antimicrobial peptides characterized for having sulfur-containing heterocycles and for being highly post-translationally modified. Numerous thiopeptides have been identified; almost all of which inhibit protein synthesis in gram-positive bacteria. These intrinsic antimicrobial properties make thiopeptides promising candidates for the development of new antibiotics. The thiopeptide micrococcin is synthesized by the ribosome and undergoes several post-translational modifications to acquire its bioactivity. In this study, we identify key interactions within the enzymatic complex that carries out cysteine to thiazole conversion in the biosynthesis of micrococcin.

Micrococcin cysteine-to-thiazole conversion through transient interactions between a scaffolding protein and two modification enzymes.

Ribosomally synthesized and post-translationally modified peptides (RiPPs) are a broad group of compounds mediating microbial competition in nature. Azole/azoline heterocycle formation in the peptide backbone is a key step in the biosynthesis of many RiPPs. Heterocycle formation in RiPP precursors is often carried out by a scaffold protein, an ATP-dependent cyclodehydratase, and an FMN-dependent dehydrogenase. It has generally been assumed that the orchestration of these modifications is carried out by a stable complex including the scaffold, cyclodehydratase and dehydrogenase. The antimicrobial RiPP micrococcin begins as a precursor peptide (TclE) with a 35-amino acid N-terminal leader and a 14-amino acid C-terminal core containing six Cys residues that are converted to thiazoles. The putative scaffold protein (TclI) presumably presents the TclE substrate to a cyclodehydratase (TclJ) and a dehydrogenase (TclN) to accomplish the two-step installation of the six thiazoles. In this study, we identify a minimal TclE leader region required for thiazole formation, we demonstrate complex formation between TclI, TclJ and TclN, and further define regions of these proteins required for complex formation. Our results point to a mechanism of thiazole installation in which TclI associates with the two enzymes in a mutually exclusive fashion, such that each enzyme competes for access to the peptide substrate in a dynamic equilibrium, thus ensuring complete modification of each Cys residue in the TclE core.

Jargonaphasia in logopenic variant primary progressive aphasia.

BACKGROUND: Logopenic variant primary progressive aphasia (lvPPA), which is most commonly an early onset variant of Alzheimer's disease (AD), is a progressive impairment in word retrieval and language expression. Clinicians often misdiagnose these patients when they present with severely unintelligible speech consistent with jargonaphasia. METHODS: We reviewed all patients presenting to a behavioral neurology program over a 23-year period who met criteria for lvPPA after completion of an evaluation extending to positron emission tomography (PET) of the brain. Among these lvPPA patients, we additionally identified and characterized those whose presentation involved incomprehensible yet fluent verbal output. RESULTS: Out of 95 patients with lvPPA, 9 (9.47%) had jargonaphasia on presentation. These patients differed from the remaining 86 patients in lacking awareness or concern for their impaired communication, having worse mental status scale scores, greater auditory comprehension difficulty, and more bilateral temporo-parietal hypometabolism. In addition, 44.4% of those with jargonaphasia, compared to 14% of those without, were bi/multilingual. CONCLUSION: Nearly 1 in 10 patients with lvPPA present with severely unintelligible speech. These patients have disease extending to bilateral temporoparietal areas affecting language comprehension and disease awareness. Jargonaphasia can be a confusing presentation of AD and must be differentiated from other progressive aphasias, Wernicke's aphasia, and the word salad of "schizoaphasia".

Three genes controlling streptomycin susceptibility in Agrobacterium fabrum.

Streptomycin (Sm) is a commonly used antibiotic for its efficacy against diverse bacteria. The plant pathogen Agrobacterium fabrum is a model for studying pathogenesis and interkingdom gene transfer. Streptomycin-resistant variants of A. fabrum are commonly employed in genetic analyses, yet mechanisms of resistance and susceptibility to streptomycin in this organism have not previously been investigated. We observe that resistance to a high concentration of streptomycin arises at high frequency in A. fabrum, and we attribute this trait to the presence of a chromosomal gene (strB) encoding a putative aminoglycoside phosphotransferase. We show how strB, along with rpsL (encoding ribosomal protein S12) and rsmG (encoding a 16S rRNA methyltransferase), modulates streptomycin sensitivity in A. fabrum. IMPORTANCE The plant pathogen Agrobacterium fabrum is a widely used model bacterium for studying biofilms, bacterial motility, pathogenesis, and gene transfer from bacteria to plants. Streptomycin (Sm) is an aminoglycoside antibiotic known for its broad efficacy against gram-negative bacteria. A. fabrum exhibits endogenous resistance to somewhat high levels of streptomycin, but the mechanism underlying this resistance has not been elucidated. Here, we demonstrate that this resistance is caused by a chromosomally encoded streptomycin-inactivating enzyme, StrB, that has not been previously characterized in A. fabrum. Furthermore, we show how the genes rsmG, rpsL, and strB jointly modulate streptomycin susceptibility in A. fabrum.

A large-scale genetic screen identifies genes essential for motility in Agrobacterium fabrum.

The genetic and molecular basis of flagellar motility has been investigated for several decades, with innovative research strategies propelling advances at a steady pace. Furthermore, as the phenomenon is examined in diverse bacteria, new taxon-specific regulatory and structural features are being elucidated. Motility is also a straightforward bacterial phenotype that can allow undergraduate researchers to explore the palette of molecular genetic tools available to microbiologists. This study, driven primarily by undergraduate researchers, evaluated hundreds of flagellar motility mutants in the Gram-negative plant-associated bacterium Agrobacterium fabrum. The nearly saturating screen implicates a total of 37 genes in flagellar biosynthesis, including genes of previously unknown function.

Toxicological effect and enzymatic disorder of non-studied emerging contaminants in Artemia salina model.

Emerging contaminants such as sunscreens, hair dyes and flame retardants have been found at important concentrations in surface water (river, lake, ocean), but their negative impact on different aquatic species is not fully known. This study evaluated the effect of benzophenone (BZ), 2,5-diaminotoluene sulfate (PTD), p-phenylenediamine (PPD) and tetrabromobisphenol A (TBPA) on survival (LC50) and the impact of sublethal concentrations (LC25) on the activity of enzymes linked to stress oxidative process in brine shrimp under two temperature conditions (22 °C and 28 °C) for 24 h and 48 h of exposure time. LC50 values obtained for each chemical substance and the activity of GST, AChE and LDH were significantly affected by the temperature conditions and exposure time. In contrast, GPx was only altered by the tested compound. TBBPA (LC50 from 17.05 up to 28.55 µg/L) and BZ (LC50 from 14.86 up to 24.49 mg/L) resulted in the most toxic substances for A. salina. The impact of dyes, such as PTD and PPD, on aquatic organisms is limited. These are the first results that show that not only dyes, but their respective by-products induce harmful effects in brine shrimp (LC50 for PTD and PPD were 23.6-396.3 and 52.0-164.9 mg/L respectively). Although this study model was very useful to evaluate the ecotoxicity of the different ECs, additional research is needed to increase available information related to the effects of dyes and other non-studied micropollutants on aquatic systems in general.

Neurological Involvement in Pediatric Patients with Acute Leukemia: A Retrospective Cohort.

Acute leukemia (AL) is an important cause of morbidity and mortality in children, and neurological manifestations (NM) are frequent. The objective of this study was to analyze neurological manifestations in children with acute leukemia from cases attended in the last five years at the Centro Médico Nacional "20 de Noviembre". METHODS: Conducting a retrospective and analytical study from 1 January 2015 to 31 December 2020 in children with AL classified according to sex, age range and AL type. Participants were grouped according the presence of NM. RESULTS: We analyzed 607 patients: 54.85% boys and 44.14% girls, with a mean age of 7.27 ± 4.54 years. When comparing groups, the NM group was significantly older (p = 0.01), and the highest prevalence was between 6 and 12 years old. ALL was predominant over the other lineages (p ≤ 0.01). The most frequent NM was CNS infiltration, seizures, headache and neuropathy. Death outcomes occurred in 18.7% of children with AML, 11.8% with ALL and 50% with MPAL (p ≤ 0.002). The NM group was associated with higher mortality during a follow-up time of 77.9 ± 49 months (44.4% vs. 8.9% deaths, NM vs. non-NM, respectively; OR = 3.3; 95% CI 2.4 to 4.6; p ≤ 0.0001). CONCLUSIONS: ALL was the most prevalent leukemia type. CNS infiltration, seizures, headache, neuropathy and PRES were the most frequent symptoms in the NM group. NM was associated with a higher mortality rate.

Association of Alzheimer Disease With Life Expectancy in People With Down Syndrome.

Importance: People with Down syndrome have a high risk of developing Alzheimer disease dementia. However, penetrance and age at onset are considered variable, and the association of this disease with life expectancy remains unclear because of underreporting in death certificates. Objective: To assess whether the variability in symptom onset of Alzheimer disease in Down syndrome is similar to autosomal dominant Alzheimer disease and to assess its association with mortality. Design, Setting, and Participants: This study combines a meta-analysis with the assessment of mortality data from US death certificates (n = 77 347 case records with a International Classification of Diseases code for Down syndrome between 1968 to 2019; 37 900 [49%] female) and from a longitudinal cohort study (n = 889 individuals; 46% female; 3.2 [2.1] years of follow-up) from the Down Alzheimer Barcelona Neuroimaging Initiative (DABNI). Main Outcomes and Measures: A meta-analysis was conducted to investigate the age at onset, age at death, and duration of Alzheimer disease dementia in Down syndrome. PubMed/Medline, Embase, Web of Science, and CINAHL were searched for research reports, and OpenGray was used for gray literature. Studies with data about the age at onset or diagnosis, age at death, and disease duration were included. Pooled estimates with corresponding 95% CIs were calculated using random-effects meta-analysis. The variability in disease onset was compared with that of autosomal dominant Alzheimer disease. Based on these estimates, a hypothetical distribution of age at death was constructed, assuming fully penetrant Alzheimer disease. These results were compared with real-world mortality data. Results: In this meta-analysis, the estimate of age at onset was 53.8 years (95% CI, 53.1-54.5 years; n = 2695); the estimate of age at death, 58.4 years (95% CI, 57.2-59.7 years; n = 324); and the estimate of disease duration, 4.6 years (95% CI, 3.7-5.5 years; n = 226). Coefficients of variation and 95% prediction intervals of age at onset were comparable with those reported in autosomal dominant Alzheimer disease. US mortality data revealed an increase in life expectancy in Down syndrome (median [IQR], 1 [0.3-16] years in 1968 to 57 [49-61] years in 2019), but with clear ceiling effects in the highest percentiles of age at death in the last decades (90th percentile: 1990, age 63 years; 2019, age 65 years). The mortality data matched the limits projected by a distribution assuming fully penetrant Alzheimer disease in up to 80% of deaths (corresponding to the highest percentiles). This contrasts with dementia mentioned in 30% of death certificates but is in agreement with the mortality data in DABNI (78.9%). Important racial disparities persisted in 2019, being more pronounced in the lower percentiles (10th percentile: Black individuals, 1 year; White individuals, 30 years) than in the higher percentiles (90th percentile: Black individuals, 64 years; White individuals, 66 years). Conclusions and Relevance: These findings suggest that the mortality data and the consistent age at onset were compatible with fully penetrant Alzheimer disease. Lifespan in persons with Down syndrome will not increase until disease-modifying treatments for Alzheimer disease are available.

Neurological Manifestations in Pediatric Patients Hospitalized for COVID-19: Experiences of the National Medical Center "20 de Noviembre" in Mexico City.

COVID-19 has affected millions of children and, while it was previously considered as a respiratory disease, neurologic involvement has also been documented. The objective of this study was to identify the neurological manifestations (NMs) and the outcomes of children with COVID-19 who attended the National Medical Center "20 de Noviembre". METHODS: A retrospective cohort study of children hospitalized for COVID-19 from April 2020 to March 2021 was conducted. Clinical-demographic data were registered. Neurologic manifestations were defined as any clinical neurological expression of the central and/or peripheral nervous system that occurred during admission or hospitalization. RESULTS: In total, 46 children with a confirmed COVID-19 result, 26 (56.5%) boys and 20 (43.5%) girls with a median age of 8.9 ± 4.6 years, constituted the study population. Half of the children showed some NMs, and this group of patients concomitantly showed acute lymphoblastic leukemia (ALL, 56%), obesity (17.3%), or acute myeloblastic leukemia (AML, 4.3%). The most frequently described NMs were headache (13, 56%), encephalopathy (10, 43.47%), and epilepsy (4, 17.39%). The mortality rate in children with NMs was 21.7% and they had a higher mortality rate when compared to those without NM p ≤ 0.025. CONCLUSIONS: NMs occurred predominantly in male children aged 6 to 12 years; ALL was the most frequent comorbidity. Headache prevailed and hypoxemia, hypocalcemia, elevated ferritin, and C-reactive protein were associated with NM. Finally, NMs were a risk factor for mortality.

Engineering efficient termination of bacteriophage T7 RNA polymerase transcription.

The bacteriophage T7 expression system is one of the most prominent transcription systems used in biotechnology and molecular-level research. However, T7 RNA polymerase is prone to read-through transcription due to its high processivity. As a consequence, enforcing efficient transcriptional termination is difficult. The termination hairpin found natively in the T7 genome is adapted to be inefficient, exhibiting 62% termination efficiency in vivo and even lower efficiency in vitro. In this study, we engineered a series of sequences that outperform the efficiency of the native terminator hairpin. By embedding a previously discovered 8-nucleotide T7 polymerase pause sequence within a synthetic hairpin sequence, we observed in vivo termination efficiency of 91%; by joining 2 short sequences into a tandem 2-hairpin structure, termination efficiency was increased to 98% in vivo and 91% in vitro. This study also tests the ability of these engineered sequences to terminate transcription of the Escherichia coli RNA polymerase. Two out of 3 of the most successful T7 polymerase terminators also facilitated termination of the bacterial polymerase with around 99% efficiency.

Invasive Subacute Pulmonary Aspergillosis After Puerperal Sepsis: Case Report.

Subacute invasive aspergillosis is an infection that locally destroys lung parenchyma, and it affects patients with mild immunocompromise. The diagnosis is made by clinical symptoms, imaging, and laboratory results related to the infection. Early diagnosis and treatment is imperative for a favorable patient outcome. In this article, we present the case of a 19-year-old woman who was admitted to the intensive care unit for puerperal sepsis where a hysterectomy was performed. During her hospitalization, she presented atelectasis of the left lung and hemodynamic instability. Chest X-ray and chest computed tomography scan were performed and showed round opacities. It was decided to perform flexible bronchoscopy with bronchoalveolar lavage. An unusual subacute form of implementation of aspergillosis was confirmed by a bronchoalveolar lavage culture that showed the presence of Aspergillus. Images taken during bronchoscopy revealed Aspergillus implantation in the lung and serum galactomannan antigen test was positive. Voriconazole was introduced, 200 mg daily. The patient showed clinical improvement and was discharged from our hospital. We conclude that subacute invasive aspergillosis is a serious infection that can lead to high mortality. Bronchoscopy with bronchoalveolar lavage allows access and effective visualization of the airway as well as sampling for Aspergillus identification.

Estrategias para promover la salud oral en gestantes durante pandemia por COVID-19 / Strategies to promote oral health in pregnant women during the COVID-19 pandemic

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Síndrome de burnout y dependencia al alcohol en estudiantes de medicina

RESUMEN Introducción: el síndrome de Burnout es una enfermedad mental causada por el estrés laboral, situación ampliamente asociada con los médicos y otros profesionales de salud, asimismo, el abuso de sustancias y la depresión también son problemas psiquiátricos que están relacionados con este ámbito. Objetivo: identificar la frecuencia de estudiantes de medicina del área clínica de la Universidad Nacional de Asunción con sospecha de Síndrome de Burnout y trastorno de abuso de alcohol. Metodología: estudio observacional, descriptivo, de corte transversal en estudiantes de medicina del área clínica de la Universidad Nacional de Asunción de Paraguay. Se utilizaron encuestas con la prueba de identificación de desórdenes de uso del alcohol (AUDIT-C), el inventario de Maslach y el screening de depresión PHQ-2. Resultados: de las 157 encuestas, el 43,9% cumplió con los criterios de Síndrome de Burnout, el 49% cumplió los criterios de abuso/dependencia de alcohol y el 38,9% tuvo criterios de alta probabilidad de trastorno depresivo mayor, de ellos la mayoría presentó ideación suicida en los últimos 12 meses. Conclusión: los resultados fueron parecidos a los hallados en la literatura, sin embargo, ciertos aspectos fueron mayores en este estudio, como el porcentaje que cumple los criterios de Síndrome de Burnout, abuso de sustancias e ideación suicida. El Síndrome de Burnout y la dependencia al alcohol son frecuentes en estudiantes de medicina y se asocian comúnmente a trastornos depresivos.

ABSTRACT Introduction: Burnout Syndrome is a mental disorder caused by occupational stress, a situation widely prevalent in doctors and other health professionals. Substance abuse and depression are also psychiatric problems that are related to this area. Objective: To identify the frequency of Burnout Syndrome and its association with Alcohol misuse in medical students in their clinical years at the National University of Asunción. Methodology: Observational, descriptive, cross-sectional study in medical students from the clinical area of the National University of Asunción, Paraguay. Surveys were used with the alcohol use disorder identification test (AUDIT-C), the Maslach inventory and the PHQ-2 depression screening. Results: Of the 157 surveys, 43.9% met the criteria for Burnout Syndrome, 49% met the criteria for alcohol misuse / dependence and 38.9% had high probability crite-ria for major depressive disorder. Most of them presented suicidal ideation in the last 12 months. Conclusion: The results were similar to those found in the literature, however, certain aspects were greater in this study, such as the percentage that meets the criteria for Burnout Syndrome, alcohol misuse and suicidal ideation. Burnout Syndrome and alcohol misuse are frequent in medical students and are commonly associated with depressive disorders.

Multiple calcifying hyperplastic dental follicles: a major diagnostic consideration in multiple pericoronal lesions - report of two cases.

BACKGROUND: Pericoronal radiolucent lesions are a common radiographic finding, but it is rare that they occur in multiple forms. Multiple calcifying hyperplastic dental follicles (MCHDF) are entities with few cases described to date; nevertheless, they appear to have a very particular phenotypic pattern. CASES PRESENTATION: Case 1: A 10-year-old male was evaluated radiographically, revealing four impacted canines, each accompanied by unilocular pericoronal radiolucency. Case 2: A 16-year-old male was planning orthodontic treatment; following his radiological evaluation all third molars were found to be accompanied with pericoronal radiolucencies. Enucleation, and third molar removal along with the pericoronal tissue were the respective treatments. Microscopically, in both cases, the specimens shown odontogenic epithelium, and type I and II calcifications in the hyperplastic follicles, all these characteristics were consistent with MCHDF. CONCLUSION: Although MCHDF are a rare entity, they must be considered in the differential diagnosis of multiple pericoronal lesions. Under the light of the current evidence, the histological findings may be relatively heterogeneous, but their integration with both the clinical data, which are apparently particular, and with the radiographic characteristics, can lead to a definitive diagnosis.

Clinical Features of Late-onset Semantic Dementia.

BACKGROUND: Semantic dementia (SD) is characterized by progressive semantic anomia extending to a multimodal loss of semantic knowledge. Although often considered an early-onset dementia, SD also occurs in later life, when it may be misdiagnosed as Alzheimer disease (AD). OBJECTIVE: To evaluate late-onset SD in comparison to early-onset SD and to AD. METHODS: We identified 74 individuals with SD and then compared those with late-onset SD (≥65 years of age) to those with early-onset SD (<65) on demographic and clinical features. We also compared a subgroup of 23 of the late-onset SD individuals with an equal number of individuals with clinically probable AD. RESULTS: Twenty-six (35.1%) of the SD individuals were late onset, and 48 (64.9%) were early onset. There were no differences between the two groups on clinical measures, although greater asymmetry of temporal involvement trended to significance in the late-onset SD group. Compared to the 23 AD individuals, the subgroup of 23 late-onset SD individuals had worse performance on confrontational naming, irregular word reading, and face recognition; however, this subgroup displayed better verbal delayed recall and constructions. The late-onset SD individuals also experienced early personality changes at a time when most individuals with AD had not yet developed behavioral changes. CONCLUSIONS: Approximately one-third of SD individuals may be late onset, and the differentiation of late-onset SD from AD can lead to better disease management, education, and prognosis. SD may be distinguished by screening for disproportionate changes in reading, face recognition, and personality.

Discrimination of radiosensitive and radioresistant murine lymphoma cells by Raman spectroscopy and SERS.

Intrinsic radiosensitivity is a biological parameter known to influence the response to radiation therapy in cancer treatment. In this study, Raman spectroscopy and surface enhanced Raman spectroscopy (SERS) were successfully used in conjunction with principal component analysis (PCA) to discriminate between radioresistant (LY-R) and radiosensitive (LY-S) murine lymphoma sublines (L5178Y). PCA results for normal Raman analysis showed a differentiation between the radioresistant and radiosensitive cell lines based on their specific spectral fingerprint. In the case of SERS with gold nanoparticles (AuNPs), greater spectral enhancements were observed in the radioresistant subline in comparison to its radiosensitive counterpart, suggesting that each subline displays different interaction with AuNPs. Our results indicate that spectroscopic and chemometric techniques could be used as complementary tools for the prediction of intrinsic radiosensitivity of lymphoma samples.

Riesgo suicida en pacientes con epilepsia de lóbulo temporal mesial farmacorresistente de la clínica de epilepsia entre Mayo de 2019 a Octubre 2019 / Suicidal risk in patients with drug-resistant mesial temporal lobe epilepsy from the epilepsy clinic from May 2019 to October 2019

La presente investigación se realizó en la Clínica de Epilepsia del Instituto Salvadoreño del Seguro Social con el fin de identificar el riesgo suicida que existe en los pacientes con epilepsia de lóbulo temporal Farmacorresistente; identificar las características sociodemográficas de los mismos y determinar según el tiempo de evolución de los síntomas, el inicio de tratamiento farmacológico y la frecuencia de crisis al mes el riesgo suicida de cada paciente. Para esta investigación se utilizó una muestra de 166 pacientes que asistieron a su cita en la clínica de epilepsia a quienes voluntariamente se les aplicó la Escala de Tendencias Suicidas de Pöldinger para medir el riesgo suicida de cada uno. Del total de encuestados hubo una predominancia del sexo femenino correspondiendo a 107 pacientes (64.5%), mientras que del sexo masculino fueron 59 pacientes (35.5%). En esta investigación se observó un porcentaje de 18.7% de pacientes (31), clasificados en las categorías de tendencia y riesgo suicida. A pesar del aparecimiento de las crisis en la infancia temprana y hasta los 18 años (50.6%) de los pacientes, no representó significancia estadística para el riesgo suicida. La única variable con asociación estadística significativa para el riesgo suicida fue el tiempo existente entre el inicio de los síntomas y el inicio de tratamiento farmacológico el cual puede impactar negativamente en el neurodesarrollo. Por tanto, dentro de la población estudiada se detectó un 18.7% de pacientes con tendencia o riesgo suicida, porcentaje que supera el reportado por algunos estudios realizados en población general. La predominancia de sexo femenino, la edad, el estado civil y factores laborales y académicos en la población estudiada no mostraron tener asociación o diferencias estadísticamente significativas con respecto a la tendencia o riesgo suicida al igual que el tiempo de evolución de la enfermedad y la frecuencia de crisis al mes, mientras que el tiempo de inicio del tratamiento farmacológico sí se asoció estadísticamente a tendencia y riesgo suicida.

Oxidation of Flame Retardant Tetrabromobisphenol A by a Biocatalytic Nanofiber of Chloroperoxidase.

BACKGROUND: Tetrabromobisphenol (TBBPA), a flame retardant compound, is considered a ubiquitous pollutant, with potential impact on the environment and human health. Several technologies have been applied to accelerate its degradation and minimize environmental impacts. Due to its aromaticity character, peroxidase enzymes may be employed to carry out its transformation in mild conditions. Therefore, the purpose of this work was to determine the capacity of the enzyme chloroperoxidase (CPO) to oxidize TBBPA in several water samples. METHODS: The oxidation capacity of CPO was evaluated in catalytic conditions using water samples from surface and groundwater, as well as effluents from wastewater treatment plants. The biocatalytic performance of CPO was improved due to its immobilization on nanofibers composed of polyvinyl alcohol and chitosan (PVA/chitosan). RESULTS: Free and immobilized CPO were able to transform more than 80% in short reaction times (60 min); producing more biodegradable and less toxic products. Particularly, the immobilized enzyme was catalytically active in a wider range of pH than the free enzyme with the possibility of reusing it up to five times. CONCLUSIONS: The biocatalytic oxidation of TBBPA under environmental conditions is highly efficient, even in complex media such as treated effluents of wastewater treatment plants.

El autocuidado del sistema genitourinario en jóvenes estudiantes universitarios / Self-care of the genitourinary system in young university students

RESUMEN Fundamento: las infecciones del sistema genitourinario se han identificado entre las más frecuentes en las consultas de la atención primaria de salud; existe un porciento significativo de estudiantes universitarios que las padecen, lo cual repercute en su calidad de vida. Objetivo: elaborar un sistema de actividades para promover el autocuidado del sistema genitourinario en los estudiantes universitarios. Métodos: se realizó una investigación de desarrollo en 2015, en la Facultad de Tecnología de la Salud. Se utilizaron métodos teóricos: histórico-lógico, analítico-sintético e inductivo-deductivo; del nivel empírico: análisis de documentos, observación, cuestionarios y entrevistas a los jóvenes y profesores, y el criterio de especialistas para valorar la propuesta. Resultados: se constató poca percepción de riesgo de los factores que provocan afectaciones en el sistema genitourinario por los jóvenes estudiantes, no habían concientizado el valor del autocuidado para la preservación de su salud y no lo asumían como influyente en la calidad de vida; omitían la responsabilidad individual en la prevención y control de las causas que ejercen influencias negativas en su organismo, por lo que se elaboró un sistema de actividades que fue valorado por criterios de especialistas. Conclusiones: el sistema elaborado promueve el autocuidado del sistema genitourinario a través de la articulación de actividades curriculares y extracurriculares que fomentan actitudes positivas hacia el cuidado del cuerpo y el mejoramiento de la calidad de vida; fue valorado como pertinente y adecuado a los propósitos para los que fue creado.

ABSTRACT Background: the genitourinary system infections have been identified among the most frequent in primary health care consultations; there is a significant percentage of university students who suffer from them, which affect their quality of life. Objective: to develop a system of activities to promote self-care of the genitourinary system in university students. Methods: a development research was carried out in 2015, at the Faculty of Health Technology. Theoretical methods were used: historical-logical, analytic-synthetic and inductive-deductive; empirical ones: analysis of documents, observation, questionnaires and interviews with young people and teachers, and the criteria of specialists to assess the proposal. Results: there was little risk perception of the factors that cause affectations in the genitourinary system of young students, they had not been aware of the self-care value for the preservation of their health and they did not assume it as influencing in life quality; they omitted the individual responsibility in the prevention and control of the causes that exert negative influences in their organism, so a system of activities was elaborated that was valued by criteria of specialists. Conclusions: the elaborated system promotes the self-care of the genitourinary system through the articulation of curricular and extracurricular activities that promote positive attitudes towards the care of the body and the improvement of quality life; it was assessed as relevant and adequate to the purposes for which it was created.

Neuropsychological Similarities and Differences Between Amnestic Alzheimer's Disease and its Non-Amnestic Variants.

BACKGROUND: The neuropsychological recognition of early-onset Alzheimer's disease (AD) can be difficult because of non-amnestic variants such as logopenic variant primary progressive aphasia (lvPPA) and posterior cortical atrophy (PCA). OBJECTIVE: This study evaluated the similarities and differences between typical amnestic AD (tAD) and lvPPA and PCA on a screening neuropsychological battery. METHODS: We enrolled 51 patients meeting NIA-AA criteria for biomarker-supported AD (amnestic or non-amnestic) and having an age of onset of <65 years of age. Based on additional recommended clinical criteria for lvPPA and PCA, the early-onset AD patients were divided into three groups (28 tAD, 9 lvPPA, 14 PCA) of comparable age and dementia severity. We then analyzed their profiles on a focused, screening neuropsychological battery for early-onset AD. RESULTS: In addition to greater variance on the Mini-Mental State Examination, the lvPPA and PCA variants had episodic memory impairment that did not significantly differ from the memory impairment in the tAD patients. Despite differences on language and visuospatial tasks, they did not significantly distinguish the lvPPA and PCA from tAD. The lvPPA group, however, was distinguishable by worse performance on measures reflecting working memory (digit span forward, memory registration). CONCLUSIONS: On neuropsychological screening, all clinical early-onset AD subtypes may have memory impairments. Screening batteries for early-onset AD should also include measures of working memory, which is disproportionately decreased in lvPPA.