Gene expression profiling of the putative RTX proteins from the marine macroalgal pathogen Nautella italica R11

Nautela italica R11, a member of Roseobacter clade, has been described as a member of the epiphytic community of the temperate red alga Delisea pulchra. Under laboratory conditions, N. italica R11 causes a temperature induced bleaching disease in D. pulchra similar to what is observed in the field, yet little is understood regarding the mechanisms of virulence in this pathogen. Analysis of the N. italica R11 genome has identified a number of genes potentially involved in virulence including those encoding surface adhesion factors, oxidative stress resistance, proteolytic enzymes and toxins. Of particular interest are the genes encoding for repeats in toxin (RTX) proteins which are common to many bacterial pathogens and have a wide range of biological and biochemical activities. Moreover a recent proteomics study found that a set of predicted RTX proteins were overrepresented in N. italica R11 cells grown at disease inducing temperatures. Therefore the aims for this study were to begin to determine the biological function of the rtx genes by describing their expression under different conditions likely to be encountered by the pathogen N. italica R11 on the surface of D. pulchra. Quantitative real time PCR (qPCR) was performed on three putative RTX genes (RR11_486, RR11_392 and RR11_222) under different conditions (elevated temperature (25°C), presence of D. pulchra crude extracts and oxidative stress). For the purpose of this investigation, combinations of molecular and classical microbiological techniques were utilized. Differential expression was observed for the three RTX genes under the experimental conditions tested. The putative RTX proteins RR11_222 and RR11_486 present the same patterns of increased gene expression in presence of D. pulchra crude extract suggesting that these two proteins may have similar function. In contrast the putative RTX protein RR11_392 present an opposite pattern of expression being expressed at the higher temperature and decreased in the presence of D. pulchra crude extract. These expression patterns are supported by the sequence analysis, which also places these proteins into different functional groups in the RTX protein family. Furthermore the sequences analysis reveals N. italica R11 RTX proteins share the characteristics of known virulence factors. The observation that rtx gene expression increases in presence of D. pulchra chemical extract and at the disease inducing temperatures suggest a possible role for the three putative RTX proteins in the process of disease in D. pulchra

Menopausa, estrogênios e disfunção endotelial: aspectos atuais

Menopause is defined as the permanent cessation of menses. Cardiovascular disease is the leading cause of death among postmenopausal women in developed countries. The disparity between the incidence of cardiovascular disease among women in pre- and postmenopause has been ascribed to the actions of endogenous estrogen on the cardiovascular system and, particularly, on the vascular endothelium. The endothelium plays an important role in cardiovascular homeostasis, either through the vascular tonus and its regulation, or through coagulation and the inflammatory response. Endothelial dysfunction is implicated in the genesis of atherosclerosis and other chronic disorders, such as diabetes mellitus and hypertension. The pharmacological use of estrogen exerts influence on the circulating levels of markers of vascular tonus, and inflammation, as well as prothrombotic, and fibrinolytic markers, but the impact of these changes on the atherosclerotic disease is still uncertain.A menopausa é definida como a cessação permanente das menstruações. A doença cardiovascular é a principal causa de mortalidade em mulheres na pós- menopausa, em países desenvolvidos. A disparidade entre a incidência de doença cardiovascular entre mulheres na pré e pós menopausa tem sido atribuída a ações do estrogênio endógeno sobre o sistema cardiovascular e, em especial, sobre a função do endotélio vascular. O endotélio tem importante papel na homestase cardiovascular, seja no controle do tônus e permeabilidade vascular, ou da coagulação e resposta inflamatória. A disfunção endotelial está implicada na gênese da aterosclerose e de outras doenças crônicas, como diabete melito e hipertensão arterial. O uso farmacológico de estrogênio exerce influência sobre concentrações circulantes de marcadores do tônus vascular, inflamatórios, pró-trombóticos e fibrinolíticos, porém o impacto destas alterações sobre a doença aterosclerótica ainda não está determinado

Distribution of the genus Boeckella (Crustacea, Copepoda, Calanoida, Centropagidae)at high latitudes in South America and the main Antarctic biogeographic regions

Copepods are present in numerous aquatic environments, playing key roles in food webs, and are thought to be useful indicators of environmental change. Boeckella is a calanoid copepod genus distributed mainly in the Southern Hemisphere, with 14 species reported at higher southern latitudes in South America and Antarctica. We present an updated database of these 14 species of Boeckella generated from a combination of three sources: 1) new field sampling data, 2) published records, and 3) Global Biodiversity Information Facility (GBIF), to provide a comprehensive description of the geographic distribution of the genus south of latitude 40°S in southern South America and the three main terrestrial biogeographic regions of Antarctica. The database includes 380 records, 62 from field sampling, 278 from the literature and 40 from GBIF. Southern South America, including the Falkland/Malvinas Islands, had the highest species richness and number of records (14 and 297, respectively), followed by the sub-Antarctic islands (5 and 34), South Orkney Islands (2 and 14), South Shetland Islands (1 and 23), Antarctic Peninsula (1 and 10) and finally continental Antarctica (1 and 2). Boeckella poppei Mrázek, 1901 is the only representative of the genus, and more widely the only terrestrial/freshwater invertebrate, currently reported from all three main biogeographic regions in Antarctica (sub-Antarctic islands, maritime and continental Antarctic). Future development of molecular systematic studies in this group should contribute to assessing the correspondence between morphological taxonomy and molecular evolutionary radiation

Association between serum dopamine and serum total cholesterol in dogs

Se investigó la relación entre el colesterol total (Colt) y la dopamina (DA) a fin de disponer de un examen accesible en consulta como es la medición del colesterol total (Colt) de manera de proyectar el comportamiento de la DA sérica. Se determinó el Colt a 50 caninos y con base a los resultados se formaron tres grupos estudio, Grupo I: 6 pacientes con Colt entre 77 y 200 mg/dl; Grupo II: 6 pacientes entre 250 y 300 mg/dl; Grupo III: 6 pacientes entre 400 y 470 mg/dl. A los 18 pacientes se les midió la DA sérica a través de HPLC acoplado a un detector electroquímico. Se encontró una amplia distribución de datos respecto de la determinación de Colt (291.8 ± 62.0 mg/ dl) y DA (68.8 ± 17.8 μg/ml) con una baja correlación entre ellos. El análisis por grupo de estudio muestra una mayor correlación de DA para bajas concentraciones de colesterol sérico, y el análisis de pendientes muestra que la variación en la concentración de DA es mayor ante pequeñas variaciones de colesterol en el grupo II.The relationship between total cholesterol (Colt) and dopamine (DA) was investigated for the possibility of having an accessible exam in consultation such as the measurement of total cholesterol (Colt) to project the behavior of serum DA. The Colt was determined in 50 dogs and based on the results three study groups were formed, Group I: 6 patients with Colt between 77 and 200 mg/dl; Group II: 6 patients between 250 and 300 mg/dl; Group III: 6 patients between 400 and 470 mg/dl. Serum DA was measured in the 18 patients through HPLC coupled to an electrochemical detector. It was found a wide distribution of data regarding the determination of Colt (291.8 ± 62.0 mg/dl) and DA (68.8 ± 17.8 μg/ml) with a low correlation between them. The analysis by study group shows a greater correlation of DA for low concentrations of serum cholesterol, and the analysis of slopes shows that the variation in the concentration of DA is greater in cases of small variations of cholesterol in group II

Salivary gland dysfunction markers in type 2 diabetes mellitus patients

Background: Diabetes mellitus (DM) is a chronic disease of the carbohydrate metabolism that, when not rigorously controlled, compromises systemic and organ integrity, thereby causing renal diseases, blindness, neuropathy, arteriosclerosis, infections, and glandular dysfunction, including the salivary glands. The aim of this study was to determine the relationship between the qualitative and quantitative parameters of salivary alteration, which are indicators of salivary gland dysfunction, and the level of metabolic control of type 2 diabetes patients. Material and Methods: A convenience sample of 74 voluntary patients with type 2 DM was selected, each of whom donated a sample of unstimulated saliva. Salivary parameters such as salivary flow rate, protein concentration, pH, and xerostomia were studied. Results: There is a positive relationship between the level of metabolic control measured with HbA1 and the protein concentration in saliva (Spearman rho = 0.329 and p = 0.004). The same assay showed an inverse correlation between HbA1 and pH (Spearman rho = -0.225 and p = 0.05). Conclusions: The protein concentration in saliva and, to a lesser extent, the pH may be useful as glandular dysfunction indicators in DM2 patients

Evaluación cuantitativa y cualitativa de la satisfacción en la enseñanza de la Patología en estudiantes de medicina en una universidad compleja chilena

The subjects of General Pathology and Anatomical Pathology are taught during the fifth and sixth semester of the Medicine program at the University of Concepción. In these subjects, a flipped classroom teaching style is used, and a practical activity called "Design of Clinical-Pathological Cases" (DCPC) is carried out. This activity is initiated in the surgical pathology room, where students experience in a real way the work of the pathologist in groups of 3 to 4 people. They perform tasks ranging from macroscopic dictation to microscopic diagnosis, culminating in a final presentation of the case to students and teachers. An observational analytical cross-sectional study was conducted on a sample of 87 students who took both subjects. A quantitative descriptive analysis and a qualitative content analysis method were performed, coding and classifying the responses from 2 instruments. The overall satisfaction with the DCPC activity was 82.4%, being perceived as innovative and useful for the development of practical skills and theoretical learning in pathology, that better prepares students to face real-world challenges as healthcare professionals. The study highlights the importance of considering students' preferences and needs when designing teaching strategies. The qualitative evaluation of the DCPC activity and subjects provided valuable information for continuous improvement, reinforcing the importance of incorporating them into teaching evaluations. It is concluded that the practical DCPC activity helps medical students better understand the macroscopic and microscopic aspects of Pathological Anatomy, surpassing even the flipped classroom approach. The combination of student-centered approaches, real-world work environments, adequate teaching support, and quality study materials can lead to a more effective and satisfying learning experience for students in these disciplines.Las asignaturas de Patología general y Anatomía patológica son impartidas durante el quinto y sexto semestre de la carrera de Medicina de la Universidad de Concepción. En estas se utiliza un estilo de enseñanza tipo aula invertida y se realiza una actividad práctica de “Diseño de Casos Clínico-Patológicos” (DCCP), iniciada en sala de patología quirúrgica, donde los estudiantes vivencian en forma real el trabajo del anatomopatólogo en grupos de 3 a 4 personas, realizando desde el dictado macroscópico hasta el diagnóstico microscópico, con una presentación final del caso a estudiantes y docentes. Se realizó un estudio observacional analítico transversal a una muestra de 87 estudiantes que cursaron ambas asignaturas. Se efectuó un análisis descriptivo cuantitativo y un método cualitativo de análisis de contenido, codificándose y clasificándose las respuestas de 2 instrumentos. La satisfacción general de la actividad DCCP fue de 82,4%, siendo percibida como innovadora y útil para el desarrollo de habilidades y aprendizajes teóricos de patología, que prepara a los alumnos de mejor manera para enfrentar los desafíos del mundo real como profesionales de la salud. No se debe olvidar la importancia de considerar las preferencias y necesidades de los estudiantes al diseñar estrategias de enseñanza. La evaluación cualitativa de la actividad DCCP y de las asignaturas entregó valiosa información para un mejoramiento continuo; reafirmando la importancia de incorporar éstas en las evaluaciones de prácticas docentes. Se concluye que la actividad práctica DCCP ayuda de mejor forma a los estudiantes de medicina a entender los aspectos macroscópicos y microscópicos de la Anatomía Patológica; superando incluso al aula invertida. La combinación de enfoques centrados en el alumno, trabajo en entornos reales, un apoyo docente adecuado y material de estudio de calidad puede conducir a una experiencia de aprendizaje más efectiva y satisfactoria para los estudiantes en estas disciplinas

Laevilacunaria (Mollusca, Gastropoda) in the Southern Ocean: A comprehensive occurrence dataset

The present dataset is a compilation of georeferenced occurrences of the littorinid genus Laevilacunaria Powell, 1951 (Mollusca, Gastropoda) in the Southern Ocean. Occurrence data were obtained from field expeditions (Antarctic and sub-Antarctic sampling) between 2015 and 2022, together with a review of published literature including records from 1887 to 2022. Three Laevilacunaria species have been recorded from the Southern Ocean: Laevilacunaria bennetti, L. antarctica and L. pumilio.The present dataset includes 75 occurrences, representing the most exhaustive database of this Antarctic and sub-Antarctic littorinid genus. The publication of this data paper was funded by the Belgian Science Policy Office (BELSPO, contract n°FR/36/AN1/AntaBIS) in the Framework of EU-Lifewatch as a contribution to the SCAR Antarctic biodiversity portal (biodiversity.aq)

Survivors and colonizers: Contrasting biogeographic histories reconciled in the Antarctic freshwater copepod Boeckella poppei

Two main hypotheses have been proposed to explain the contemporary distribution of Antarctic terrestrial biota. We assess whether the current distribution of maritime Antarctic populations of the freshwater copepod Boeckella poppei is the result of (1) a post-Last Glacial Maximum (LGM) colonization, or whether (2) the species survived in regional glacial refugia throughout the LGM and earlier glaciations. Using 438 specimens from 34 different sampling sites across Southern South America, South Georgia, South Orkney Islands, South Shetland Islands and the Antarctic Peninsula, we analysed mitochondrial and nuclear sequences to uncover patterns of genetic diversity and population structure. We also performed median-joining haplotype network, phylogenetic reconstruction and divergence time analyses. Finally, we evaluated past demographic changes and historical scenarios using the Approximate Bayesian Computation (ABC) method. Our data support the existence of two clades with different and contrasting biogeographic histories. The first clade has been present in maritime Antarctica since at least the mid-Pleistocene, with the South Orkney Islands the most likely refugial area. The second clade has a broader distribution including southern South America, South Georgia, South Shetland Islands and the Antarctic Peninsula. The ABC method identified long-distance dispersal (LDD) colonization event(s) from southern South America to South Georgia and the maritime Antarctic after the LGM deglaciation, supporting more recent colonization of Antarctic locations. The current Antarctic and sub-Antarctic distribution of B. poppei is likely derived from two independent biogeographic events. The combination of both (1) post-LGM colonization from southern South America and (2) longer-term persistence in in situ regional refugia throughout glacial periods challenges current understanding of the biogeographic history of Antarctic freshwater biota. Re-colonization of ice-impacted Antarctic areas would have occurred following a LDD and Establishment model, pointing to the existence of possible post-dispersal barriers, despite widely assumed high passive dispersal capacity in freshwater invertebrates