Inorganic Polyphosphate Affects Biofilm Assembly, Capsule Formation, and Virulence of Hypervirulent ST23 Klebsiella pneumoniae.

The emergence of hypervirulent Klebsiella pneumoniae (hvKP) strains poses a significant threat to public health due to high mortality rates and propensity to cause severe community-acquired infections in healthy individuals. The ability to form biofilms and produce a protective capsule contributes to its enhanced virulence and is a significant challenge to effective antibiotic treatment. Polyphosphate kinase 1 (PPK1) is an enzyme responsible for inorganic polyphosphate synthesis and plays a vital role in regulating various physiological processes in bacteria. In this study, we investigated the impact of polyP metabolism on the biofilm and capsule formation and virulence traits in hvKP using Dictyostelium discoideum amoeba as a model host. We found that the PPK1 null mutant was impaired in biofilm and capsule formation and showed attenuated virulence in D. discoideum compared to the wild-type strain. We performed a proteomic analysis to gain further insights into the underlying molecular mechanism. The results revealed that the PPK1 mutant had a differential expression of proteins involved in capsule synthesis (Wzi-Ugd), biofilm formation (MrkC-D-H), synthesis of the colibactin genotoxin precursor (ClbB), as well as proteins associated with the synthesis and modification of lipid A (ArnB-LpxC-PagP). These proteomic findings corroborate the phenotypic observations and indicate that the PPK1 mutation is associated with impaired biofilm and capsule formation and attenuated virulence in hvKP. Overall, our study highlights the importance of polyP synthesis in regulating extracellular biomolecules and virulence in K. pneumoniae and provides insights into potential therapeutic targets for treating K. pneumoniae infections.

Tétanos: una enfermedad inmunoprevenible / Tetanus: an immunopreventable disease

Resumen El tétanos es causado por el Clostridium tetani, una bacteria ubicua que frente a condiciones de anaerobio sis puede sintetizar y liberar sus toxinas, responsables del cuadro clínico. Dado que es una bacteria que se encuentra en el suelo y en el tracto gastrointestinal de muchas especies, se trata de una enfermedad no erra dicable pero si controlable a través de la inmunización para la prevención. Las tasas de inmunización han disminuido en los últimos años, evento que se ha acentuado durante la COVID-19. Se presentan a continuación dos casos clínicos in gresados durante el año 2022. El primero es un hombre de 39 años cuya puerta de entrada fue una herida de arma de fuego conevolución favorable y el segundo caso se trata de una mujer de 83 años sin puerta de entrada clara quien falleció durante su internación en terapia intensiva. La importancia de esta presentación es mos trar la gravedad de la enfermedad, cuyavaloración es principalmente clínica y no debe escapar al algoritmo de diagnósticos diferenciales, acentuando que se debe instaurar el tratamiento de forma precoz o frente a la duda consultar con un centro especializado. Asímismo, es importante revisar las tasas de inmuni zación en nuestro país y los cambios que se presentaron durante la pandemia, teniendo en cuenta, como se ha expuesto previamente, se trata de una enfermedad in munoprevenible.

Abstract Tetanus is an infectious disease caused by a ubiqui tous bacterium Clostridium tetani, that synthesizes and releasesa potent neurotoxin under anaerobic conditions, which is responsible for the clinical manifestations. As it is found in soil contaminated with animal and human excreta, it is difficult to eradicate but it may be prevented by immunization. Immunization rate has decreased in the last years, especially during the COVID-19 pandemic. We report two cases of tetanus, attended during 2022. A 39-year-old man whose entry route was a gunshot wound and he was discharged from the intensive care unit (ICU) and a second case of an 83-year-old woman with unknown entry point, who died during her ICU stay. The cases reported highlight that it is a life-threatening disease, its diagnosis is mainly clinical and it should be in the algorithm of differential diagnoses. We emphasize about the prompt treatment administration or consulta tion to a specialized healthcare center. The importance of this presentation is to show the severity of the dis ease, whose assessment is mainly clinical and should not escape the algorithm of differential diagnoses, em phasizing that treatment should be instituted early or when in doubt consult a specialized center. In addition to this, it is important to check theimmunization rate in our country, especially during thepandemic, becauseit is a vaccine-pre ventable disease.

Community health worker navigation to improve allostatic load: The Integrated Population Health (IPOP) study.

Background: Social determinants of health (SDOH) and cumulative stress contribute to chronic disease development. The physiological response to repeated stressors typical of lower-income environments can be measured through allostatic load - a composite measure of cardiovascular, metabolic, and immune variables. Healthcare systems have employed patient navigation for social and medical needs to improve SDOH that has demonstrated limited impact on chronic disease outcomes. This study evaluates a novel community health worker navigation intervention developed using behavioral theories to improve access to social and medical services and provide social support for poverty stressed adults. Methods: The Integrated Population Health Study (IPOP) study is a randomized, parallel two arm study evaluating community health worker navigation in addition to an existing integrated population health program (IPOP CHW) as compared to Usual Care (population health program only, IPOP) on allostatic load and chronic disease risk factors. IPOP CHW participants receive a 10-month navigation intervention. Results: From 381 screened individuals, a total of 202 participants (age 58.15 ± 12.03 years, 74.75 % female, 79.21 % Black/African American, 17.33 % Hispanic) were enrolled and randomized to IPOP CHW (n = 100) or IPOP Only (n = 102). Conclusion: This study will evaluate whether CHW navigation, using a structured intervention based on health behavior theories, can effectively guide poverty stressed individuals to address social and medical needs to improve allostatic load-a composite of cumulative stress and physiological responses. Healthcare systems, nonprofit organizations, and governmental entities are interested in addressing SDOH to improve health, thus developing evidence-based interventions could have broad clinical and policy implications.

[Tetanus: an immunopreventable disease]. / Tétanos: una enfermedad inmunoprevenible.

Tetanus is an infectious disease caused by a ubiquitous bacterium Clostridium tetani, that synthesizes and releasesa potent neurotoxin under anaerobic conditions, which is responsible for the clinical manifestations. As it is found in soil contaminated with animal and human excreta, it is difficult to eradicate but it may be prevented by immunization. Immunization rate has decreased in the last years, especially during the COVID-19 pandemic. We report two cases of tetanus, attended during 2022. A 39-year-old man whose entry route was a gunshot wound and he was discharged from the intensive care unit (ICU) and a second case of an 83-year-old woman with unknown entry point, who died during her ICU stay. The cases reported highlight that it is a life-threatening disease, its diagnosis is mainly clinical and it should be in the algorithm of differential diagnoses. We emphasize about the prompt treatment administration or consultation to a specialized healthcare center. The importance of this presentation is to show the severity of the disease, whose assessment is mainly clinical and should not escape the algorithm of differential diagnoses, emphasizing that treatment should be instituted early or when in doubt consult a specialized center. In addition to this, it is important to check theimmunization rate in our country, especially during thepandemic, becauseit is a vaccine-preventable disease.

El tétanos es causado por el Clostridium tetani, una bacteria ubicua que frente a condiciones de anaerobiosis puede sintetizar y liberar sus toxinas, responsables del cuadro clínico. Dado que es una bacteria que se encuentra en el suelo y en el tracto gastrointestinal de muchas especies, se trata de una enfermedad no erradicable pero si controlable a través de la inmunización para la prevención. Las tasas de inmunización han disminuido en los últimos años, evento que se ha acentuado durante la COVID-19. Se presentan a continuación dos casos clínicos ingresados durante el año 2022. El primero es un hombre de 39 años cuya puerta de entrada fue una herida de arma de fuego conevolución favorable y el segundo caso se trata de una mujer de 83 años sin puerta de entrada clara quien falleció durante su internación en terapia intensiva. La importancia de esta presentación es mostrar la gravedad de la enfermedad, cuyavaloración es principalmente clínica y no debe escapar al algoritmo de diagnósticos diferenciales, acentuando que se debe instaurar el tratamiento de forma precoz o frente a la duda consultar con un centro especializado. Asímismo, es importante revisar las tasas de inmunización en nuestro país y los cambios que se presentaron durante la pandemia, teniendo en cuenta, como se ha expuesto previamente, se trata de una enfermedad inmunoprevenible.

Clinical and pulmonary function analysis in long-COVID revealed that long-term pulmonary dysfunction is associated with vascular inflammation pathways and metabolic syndrome.

Introduction: Long-term pulmonary dysfunction (L-TPD) is one of the most critical manifestations of long-COVID. This lung affection has been associated with disease severity during the acute phase and the presence of previous comorbidities, however, the clinical manifestations, the concomitant consequences and the molecular pathways supporting this clinical condition remain unknown. The aim of this study was to identify and characterize L-TPD in patients with long-COVID and elucidate the main pathways and long-term consequences attributed to this condition by analyzing clinical parameters and functional tests supported by machine learning and serum proteome profiling. Methods: Patients with L-TPD were classified according to the results of their computer-tomography (CT) scan and diffusing capacity of the lungs for carbon monoxide adjusted for hemoglobin (DLCOc) tests at 4 and 12-months post-infection. Results: Regarding the acute phase, our data showed that L-TPD was favored in elderly patients with hypertension or insulin resistance, supported by pathways associated with vascular inflammation and chemotaxis of phagocytes, according to computer proteomics. Then, at 4-months post-infection, clinical and functional tests revealed that L-TPD patients exhibited a restrictive lung condition, impaired aerobic capacity and reduced muscular strength. At this time point, high circulating levels of platelets and CXCL9, and an inhibited FCgamma-receptor-mediated-phagocytosis due to reduced FcγRIII (CD16) expression in CD14+ monocytes was observed in patients with L-TPD. Finally, 1-year post infection, patients with L-TPD worsened metabolic syndrome and augmented body mass index in comparison with other patient groups. Discussion: Overall, our data demonstrated that CT scan and DLCOc identified patients with L-TPD after COVID-19. This condition was associated with vascular inflammation and impair phagocytosis of virus-antibody immune complexes by reduced FcγRIII expression. In addition, we conclude that COVID-19 survivors required a personalized follow-up and adequate intervention to reduce long-term sequelae and the appearance of further metabolic diseases.

Proteomic and toxicological analysis of the response of dinoflagellate Alexandrium catenella to changes in NaNO3 concentration.

Dinoflagellates of the genus Alexandrium cause Harmful Algal Blooms (HABs) in coastal waters worldwide, damaging marine environments, aquaculture, and human health. They synthesize potent neurotoxic alkaloids known as PSTs (i.e., Paralytic Shellfish Toxins), the etiological agents of PSP (i.e., Paralytic Shellfish Poisoning). In recent decades, the eutrophication of coastal waters with inorganic nitrogen (e.g., nitrate, nitrite, and ammonia) has increased the frequency and scale of HABs. PSTs concentrations within Alexandrium cells can increase by up to 76% after a nitrogen enrichment event; however, the mechanisms that underlie their biosynthesis in dinoflagellates remains unclear. This study combines mass spectrometry, bioinformatics, and toxicology and investigates the expression profiles of PSTs in Alexandrium catenella grown in 0.4, 0.9 and 1.3 mM NaNO3. Pathway analysis of protein expression revealed that tRNA amino acylation, glycolysis, TCA cycle and pigment biosynthesis were upregulated in 0.4 mM and downregulated in 1.3 mM NaNO3 compared to those grown in 0.9 mM NaNO3. Conversely, ATP synthesis, photosynthesis and arginine biosynthesis were downregulated in 0.4 mM and upregulated in 1.3 mM NaNO3. Additionally, the expression of proteins involved in PST biosynthesis (sxtA, sxtG, sxtV, sxtW and sxtZ) and overall PST production like STX, NEO, C1, C2, GTX1-6 and dcGTX2 was higher at lower nitrate concentrations. Therefore, increased nitrogen concentrations increase protein synthesis, photosynthesis, and energy metabolism and decrease enzyme expression in PST biosynthesis and production. This research provides new clues about how the changes in the nitrate concentration can modulate different metabolic pathways and the expression of PST biosynthesis in toxigenic dinoflagellates.

Coinfección COVID-19 y tuberculosis: experiencia de una terapia intensiva durante el periodo enero 2020-junio 2022 / COVID-19 and tuberculosis co-infection: experience of an intensive care unit during the period of January-june 2022

Antecedentes: Se ha demostrado que la coinfección tu-berculosis y COVID-19 presenta peor evolución clínica. La inmunidad protectora se debilita frente a esta situación, generando fallo en el control de ambas infecciones, reac-tivación de formas latentes de tuberculosis y progresión exacerbada de los casos activos. Asimismo, la terapia con corticoides utilizada dentro del tratamiento de infecciones graves por COVID-19 puede generar inmunosupresión y precipitar la progresión de la tuberculosis.Objetivos: Describir las características clínicas, presenta-ción y evolución de los pacientes críticos con coinfección COVID-19 y tuberculosis. Evaluar la incidencia y letalidad de la asociación COVID-19 y tuberculosis en cuidados in-tensivos. Materiales y métodos: Se realizó un estudio retrospectivo, descriptivo. Se revisaron 12 historias clínicas de pacientes con coinfección COVID-19-tuberculosis sobre 1014 histo-rias clínicas de pacientes ingresados con diagnóstico de COVID-19, durante el periodo comprendido enero 2020 y junio 2022. Se utilizó estadística descriptiva. Resultados y discusión: Sobre un total de 1014 historias clínicas, se encontraron 12 pacientes con coinfección (in-cidencia de 0,011). La letalidad global en cuidados inten-sivos fue del 75%, a los 45 días fue del 83,3%, duplicando la letalidad general de los pacientes COVID-19 no coinfec-tados ingresados durante el mismo periodo (75% versus 37%). Los pacientes que requirieron ingreso a ventilación RESUMENARTÍCULO ORIGINALmecánica tuvieron una letalidad del 100% y aquellos que tenían infección por virus de inmunodeficiencia adquirida presentaron una letalidad de 100%. Resulta importante describir los hallazgos y alertar sobre la evolución desfavorable de aquellos pacientes que pre-sentan esta asociación a fin de optimizar el manejo y espe-cialmente recomendar la búsqueda de coinfección cuando el criterio clínico lo requiera

Background: Coinfection with tuberculosis and COVID-19 has been shown to have a worse clinical course. Protective immunity is weakened in this situation, leading to failure to control both infections, reactivation of latent forms of TB and exacerbated progression of active cases. Furthermore, corticosteroid therapy used in the treatment of severe COVID-19 infections can lead to immunosuppression and precipitate TB progression.Objectives: To describe the clinical characteristics, presentation and evolution of critically ill patients with COVID-19 and tuberculosis co-infection.To evaluate the incidence and lethality of COVID-19 and tuberculosis association in intensive care.Materials and methods: A retrospective, descriptive study was conducted. Twelve medical records of patients aged 18 years or older admitted to intensive care with a diagnosis of COVID-19 during the period January 2020 to July 2022 were reviewed. Descriptive statistics were used.Results and discussion: Out of a total of 1014 medical records, 12 patients were found with co-infection (incidence 0.011). The global intensive care case fatality was 75%, at 45 days it was 83.3%. This was twice the overall case fatality of non-co-infected COVID-19 patients admitted during the same period (75% versus 37%). Patients requiring admission to mechanical ventilation had a 100% case fatality and those with acquired immunodeficiency virus infection had a 100% case fatality.It is important to describe the findings and to alert to the worse evolution of those patients presenting with this association, in order to improve management and recommend searching for co-infection when clinical criteria require it

Differential gene expression analysis in the scallop Argopecten purpuratus exposed to altered pH and temperature conditions in an upwelling-influenced farming area.

Increased carbon dioxide in the atmosphere and its absorption across the ocean surface will alter natural variations in pH and temperature levels, occurring in coastal upwelling ecosystems. The scallop Argopecten purpuratus, one of the most economically important species farmed in northern Chile, has been shown to be vulnerable to these environmental drivers. However, the regulatory responses at the gene-level of scallops to these climate stressors remain almost unknown. Consequently, we used an orthogonal experimental design and RNAseq approach to analyze the acute effects of variability in pH and temperature on gene expression in the muscle tissue of A. purpuratus. In respect to control conditions (pH ~ 8.0/ 14 °C), the influence of low pH (~ 7.7) and temperature (14 °C) induced the activation of several genes associated with apoptotic signaling pathways and protein localization to plasma membrane. Elevated temperature (18 °C) and pH (~8.0) conditions increased the expression of transcripts associated with the activation of muscle contraction, regulation, and sarcomere organization effects on muscle tissue. In scallops exposed to low pH and elevated temperature, the genes expressed were differentially associated with the oxidation-reduction process, signal translation, and positive regulation of GTPase activity. These results indicated that the differentially expressed genes under the experimental conditions tested are mainly related to the mitigation of cellular damage and homeostasis control. Our results add knowledge about the function of the adductor muscle in response to stressors in scallops. Furthermore, these results could help in the identification of molecular biomarkers of stress necessary to be integrated into the aquaculture programs for the mitigation of climate change.

Long term environmental variability modulates the epigenetics of maternal traits of kelp crabs in the coast of Chile.

The methylation of DNA is an environmentally inducible epigenetic mechanism reflecting the short-term ecological and environmental background of populations. Marine invertebrate populations, which spread along a latitudinal cline, are particularly suitable for profiling DNA methylation, due to the heterogenous environmental conditions experienced. We used the MSAP (Methylation Sensitive Amplified Polymorphism) technique to investigate the natural variation in DNA methylation of different female's tissues (muscle, gonads, and gills) and early-stage eggs from five populations of the kelp crab Taliepus dentatus, distributed along a latitudinal cline in the coast of Chile. We assessed whether, (1) the distribution of DNA methylation profiles can be associated with the temporal variability of long term (18 years) climatologies (sea surface temperature, turbidity and productivity) and (2) the epigenetic diversity of eggs is related to the population-level phenotypic variability of several maternal investment traits (egg volume, egg weight, egg lipids and fecundity). The DNA methylation of eggs correlated positively and negatively with the long term variability in productivity and sea surface temperature, respectively. Furthermore, the diversity of DNA methylation of eggs correlated positively with the population-level phenotypic variability of several maternal investment traits, suggesting a key role of epigenetic mechanisms in generating phenotypic variability at population level for this species. We provide evidence of a strong link between the temporal variability of long term climatologies with the epigenetic profiles of key early ontogenetic traits associated with the maternal investment of kelp crabs. These modulating mechanisms can hence contribute early to phenotypic variability at population levels in response to local and past environmental fluctuation.

Neuropsychological aspects of bipolar disorder.

Bipolar disorder (BD) is a chronic condition with serious consequences on the health and functionality of patients who suffer from it, with a high heritability and segregation, and aprevalence of between 1% and 2%. Neuropsychological deficits have been implicated as a very important issue related to BD prognosis, so a review was conducted of these deficits, the related factors and their functional consequences. It has been determined that the presence of neuropsychological deficits can vary in patients with BD according to their mood state, with a great influence of depressive symptoms on the cognitive variability of patients with respect to the general population and differences with respect to patients in the manic phase. In euthymic patients, the most affected cognitive domains are those of memory, attention, and executive function, associated with a more severe disease, sociodemographic vulnerability factors, and stable over time. A relationship has been found between poor cognitive performance, especially executive dysfunction, and objective functional deficit. Furthermore, cognitive differences have been outlined between BD and other serious mental illnesses that are described in this review.

Proteogenomic analysis in an early onset diffuse gastric cancer patient revealed alterations in PIK3R1, TP53, SMAD4 and a potential role of the PI3K-AKT and EGFR pathways: a case report.

Background: Early-onset gastric cancers (EOGC) are poor prognosis hard-to treat malignancies that affect young individuals (<45 years old). Case Description: Herein we describe the case of a 26-year-old female EOGC patient that initially displayed stable disease after first-line CAPOX plus immunotherapy. However, patient eventually developed progressive disease and was consecutively switched to paclitaxel plus ramucirumab, and palliative irinotecan. In search for therapeutic alternatives a proteo-genomic analysis was performed in a tissue biopsy taken after the first progression. Our analyses found a total of 18 somatic mutations, including TP53 and PIK3R1, and a previously unreported germline alteration in the tumor suppressor SMAD4. Also, our proteomic analysis found 62 proteins previously documented as "enriched in stomach cancer" and AKT/mTOR and EGFR as pathways with therapeutic potential. Unfortunately, the clinical utility of AKT/mTOR inhibitors or EGFR targeted therapies could not be assessed. Conclusions: As explained above EOGC is a growing health concern that affects young individuals. Furthermore, the reported case displayed a poor response to standard therapy including checkpoint inhibitors and chemotherapy despite the presence of biomarkers that predict a favorable outcome. Future studies should adopt alternative approaches to find novel, more effective therapies.

Aspectos neuropsicológicos del trastorno afectivo bipolar / Neuropsychological Aspects of Bipolar Disorder

RESUMEN El trastorno afectivo bipolar (TAB) es una entidad crónica con graves efectos para la salud y la funcionalidad de los pacientes que la sufren, con una alta carga de heredabilidad y segregabilidad y una prevalencia que oscila entre el 1 y el 2%. Las alteraciones neuropsicológicas son características importantes relacionadas con su pronóstico, por lo cual se hizo una revisión narrativa sobre estas alteraciones, los factores asociados y sus consecuencias funcionales. Se ha determinado que la presencia de alteraciones neuropsicológicas puede variar en los pacientes con TAB según la fase anímica en que se encuentren, con una gran influencia de los síntomas depresivos en la variabilidad cognitiva de los pacientes respecto a la población general y diferencias respecto a los pacientes en fase maniaca. En pacientes eutímicos, los dominios cognitivos más afectados son los de memoria, atención y función ejecutiva, asociados con una enfermedad más grave, factores sociodemográficos de vulne rabilidad y sin interacción con el tiempo de evolución. Se ha encontrado una relación entre el mal rendimiento cognitivo, especialmente la disfunción ejecutiva y el déficit funcional objetivo; además, se han perfilado diferencias cognitivas entre el TAB y otras enfermedades mentales graves que se describen en la revisión.

ABSTRACT Bipolar disorder (BD) is a chronic condition with serious consequences on the health and functionality of patients who suffer from it, with a high heritability and segregation, and a prevalence of between 1% and 2%. Neuropsychological deficits have been implicated as a very important issue related to BD prognosis, so a review was conducted of these deficits, the related factors and their functional consequences. It has been determined that the presence of neuropsychological deficits can vary in patients with BD according to their mood state, with a great influence of depressive symptoms on the cognitive variability of patients with respect to the general population and differences with respect to patients in the manic phase. In euthymic patients, the most affected cognitive domains are those of memory, attention, and executive function, associated with a more severe disease, sociodemographic vulnerability factors, and stable over time. A relationship has been found between poor cognitive performance, especially executive dysfunction, and objective functional deficit. Furthermore, cognitive differences have been outlined between BD and other serious mental illnesses that are described in the review.

Physical-chemical factors influencing the vertical distribution of phototrophic pico-nanoplankton in the Oxygen Minimum Zone (OMZ) off Northern Chile: The relative influence of low pH/low O2 conditions.

The vertical distribution of phytoplankton is of fundamental importance in the structure, dynamic, and biogeochemical pathways in marine ecosystems. Nevertheless, what are the main factors determining this distribution remains as an open question. Here, we evaluated the relative influence of environmental factors that might control the coexistence and vertical distribution of pico-nanoplankton associated with the OMZ off northern Chile. Our results showed that in the upper layer Synechococcus-like cells were numerically important at all sampling stations. Pico-nano eukaryotes and phototrophic nanoflagellates (PNF) also showed high abundances in the upper layer decreasing in abundance down to the upper oxycline, while only Prochlorococcus showed high abundances under oxycline and within the oxygen-depleted layer. Statistical analyses evidenced that temperature, oxygen, and carbonate chemistry parameters (pH and dissolved inorganic carbon, DIC) influenced significantly the vertical distribution of phototrophic pico-nanoplankton. Additionally, we experimentally-evaluated the combined effect of low pH/low O2 conditions on a nanophytoplankton species, the haptophyte Imantonia sp. Under control conditions (pH = 8.1; O2 = 287.5 µM, light = 169.6 µEm-2s-1), Imantonia sp. in vivo fluorescence increased over fifty times, inducing supersaturated O2 conditions (900 µM) and an increasing pH (8.5), whereas upon an experimental treatment mimicking OMZ conditions (pH = 7.5; O2 = 55.6 µM; light = 169.6 µEm-2s-1), in vivo fluorescence declined dramatically, suggesting that Imantonia sp. did not survive. Although preliminary, our study provides evidence about the role of low pH/low O2 conditions on the vertical distribution of nanophytoplankton, which deserve future attention through both fieldwork and more extended experimental experiences.

Resting-state functional nuclear magnetic resonance imaging in patients with bipolar disorder: Beyond euthymia.

INTRODUCTION: Functional nuclear magnetic resonance imaging in the resting state (R-fMRI) allows the identification of complete functional connectivity networks and the possible neuronal correlations of psychiatric disorders. The literature on R-fMRI and bipolar disorder (BD) will be reviewed, emphasising the findings in the phases of mania, hypomania and depression. METHODS: It is a narrative review of the literature in which articles were searched in PubMed and Embase, with the key words in English "bipolar disorder" AND "resting state", without limit on the date of publication. RESULTS: The studies of BD patients in the mania and hypomania phases who underwent R-fMRI show concordant results in terms of decreased functional cerebral connectivity between the amygdala and some cortical regions, which indicates that this functional connection would have some implication in the normal affect regulation. Patients in the depressive phase show a decrease in functional brain connectivity, but as there are several anatomical structures involved and neural networks reported in the studies, it is not possible to compare them. CONCLUSIONS: There is a decrease in functional connectivity in patients with BD, but current evidence does not allow establishing specific changes in specific functional brain connectivity networks. However, there are already some findings that show correlation with the patients' symptoms.

Structural neuroimaging and predominant polarity in patients with type 1 bipolar disorder from Antioquia.

INTRODUCTION: Predominant polarity (PP) has been proposed as a specifier of bipolar disorder (BD) due to its relationship with clinical and prognostic variables. It is possible that this is due to a different underlying neurobiology, in such a way that the changes found by structural nuclear magnetic resonance imaging (sMRI) in BD are different and specific. OBJECTIVES: To explore findings of structural neuroimaging in patients with BD type I (BD-I) according to PP. METHODS: Cross-sectional study that evaluated 77 patients with BD-I using the DIGS interview. PP was established using the operative definition of two-thirds of all affective episodes throughout life to classify PP as manic (MPP), depressive (DPP) or indeterminate (IPP). MRI was performed during the euthymia phase to measure intracranial structures. The data obtained was analysed using a linear regression model adjusted for confounding variables (drug use, alcohol use, psychoactive substance use) and were compared between the three groups finding the standardised mean difference (SMD). RESULTS: Differences with adequate effect size were found in three brain structures after adjusting for confounding variables, specifically in the right fusiform gyrus and the left lingual gyrus, which were greater in the DPP group than in the MPP group (SMD = 0.92; 95% CI = 0.34-1.49 and SMD = 0.78; 95% CI = 0.21-1.35). Likewise, in the right thalamus, it was shown to be greater in the IPP group compared to MPP group (SMD 0.89, 95% CI = 0.31-1.46). CONCLUSIONS: A reduction in the thickness of the right fusiform gyrus and the left lingual gyrus, as well as the right thalamic volume was observed in patients with BD-I with PPM, which supports the hypothesis that PP has a plausible neurobiological correlate and could have potential utility as a BD specifier.

Neuroimagen estructural y polaridad predominante en pacientes con trastorno afectivo bipolar tipo I de Antioquia / Structural Neuroimaging and Predominant Polarity in Patients with Type 1 Bipolar Disorder from Antioquia

RESUMEN Introducción: La polaridad predominante (PP) se ha propuesto como un especificador del trastorno afectivo bipolar (TAB) por su relación con variables clínicas y pronósticas. Es posible que esto se deba a una neurobiología subyacente distinta, de tal manera que los cambios encontrados por resonancia magnética estructural (RMe) en el TAB sean diferentes y específicos. Objetivos: Explorar hallazgos de neuroimagen estructural en pacientes con TAB I de acuerdo con la PP. Métodos: Estudio de corte transversal que evaluó a 77 pacientes con TAB I usando la entrevista DIGS. Se estableció la PP utilizando la definición operativa de los 2 tercios de todos los episodios afectivos a lo largo de la vida para clasificar la PP en maniaca (PPM), depresiva (PPD) o indeterminada (PPI). Se les realizó RMe durante la fase de eutimia para medir estructuras intracraneales. Los datos obtenidos se analizaron mediante un modelo de regresión lineal ajustado por variables de confusión (consumo de medicamentos, consumo de alcohol, consumo de sustancias psicoactivas) y se compararon entre los 3 grupos para hallar la diferencia de medias estandarizada (DME). Resultados: Se encontraron diferencias con adecuado tamaño de efecto en 3 estructuras cerebrales tras ajustar por variables de confusión, específicamente en el giro fusiforme derecho y el giro lingual izquierdo, que fueron mayores en el grupo de PPD que en el de PPM (DME = 0,92; IC95%, 0,34-1,49; DME = 0,78; IC95%, 0,21-1,35). Así mismo en el tálamo derecho, que se mostró mayor en el grupo de PPI frente al de PPM (DME = 0,89; IC95%, 0,31-1,46). Conclusiones: Se observó una reducción del espesor del giro fusiforme derecho y el giro lingual izquierdo, así como del volumen talámico derecho en pacientes con TAB I con PPM, lo que respalda la hipótesis de que la PP cuenta con un correlato neurobiológico plausible y podría tener potencial utilidad como especificador del TAB.

ABSTRACT Introduction: Predominant polarity (PP) has been proposed as a specifier of bipolar disorder (BD) due to its relationship with clinical and prognostic variables. It is possible that this is due to a different underlying neurobiology, in such a way that the changes found by structural nuclear magnetic resonance imaging (sMRI) in BD are different and specific. Objectives: To explore findings of structural neuroimaging in patients with BD type I (BD-I) according to PP. Methods: Cross-sectional study that evaluated 77 patients with BD-I using the DIGS interview. PP was established using the operative definition of two-thirds of all affective episodes throughout life to classify PP as manic (MPP), depressive (DPP) or indeterminate (IPP). MRI-was performed during the euthymia phase to measure intracranial structures. The data obtained was analyzed using a linear regression model adjusted for confounding variables (drug use, alcohol use, psychoactive substance use) and were compared between the three groups finding the standardized mean difference (SMD). Results: Differences with adequate effect size were found in three brain structures after adjusting for confounding variables, specifically in the right fusiform gyrus and the left lingual gyrus, which were greater in the DPP group than in the MPP group (SMD = 0.92; 95% CI = 0.34 to 1.49 and SMD = 0.78; 95% CI = 0.21 to 1.35). Likewise, in the right thalamus, it was shown to be greater in the IPP group compared to MPP group (SMD 0.89, 95% CI = 0.31 to 1.46). Conclusions: A reduction in the thickness of the right fusiform gyrus and the left lingual gyrus, as well as the right thalamic volume was observed in patients with BD-I with PPM, which supports the hypothesis that PP has a plausible neurobiological correlate and could have potential utility as a BD specifier.

Resonancia magnética nuclear funcional en estado de reposo en pacientes con trastorno bipolar: más allá de la eutimia / Resting-state functional nuclear magnetic resonance imaging in patients with bipolar disorder: beyond euthymia

Resumen Introducción: La resonancia magnética funcional en estado de reposo (RMf-ER) permite identificar redes de conectividad funcional completas y los posibles correlatos neuronales de trastornos psiquiátricos. Se revisa la literatura sobre RMf-ER y trastorno bipolar (TB) haciendo énfasis en los hallazgos en las fases de manía, hipomanía y depresión. Métodos: Es una revisión narrativa de la literatura en la que se buscaron artículos en PubMed y EMBASE con las palabras clave en inglés "bipolar disorder" AND "resting state", sin límite en la fecha de publicación. Resultados: Los estudios de pacientes con TB en fases de manía e hipomanía sometidos a RMf-ER muestran resultados concordantes en cuanto a la disminución de la conectividad funcional cerebral entre la amígdala y algunas regiones corticales, lo cual indica que esta conexión funcional tendría alguna implicación en la regulación normal del afecto. Los pacientes en fase depresiva muestran disminución en la conectividad funcional cerebral, pero como son varias las estructuras anatómicas implicadas y las redes neuronales reportadas en los estudios, no es posible compararlos. Conclusiones: Hay disminución en la conectividad funcional en los pacientes con TB, pero la evidencia actual no permite establecer cambios específicos en redes de conectividad funcional cerebral puntuales. Sin embargo, ya hay algunos hallazgos que muestran correlación con la clínica de los pacientes.

ABSTRACT Introduction: imaging in the resting state (R-fMRI) Functional nuclear magnetic allows the identification of complete functional connectivity networks and the possible resonance neuronal correlations of psychiatric disorders. The literature on R-fMRI and bipolar disorder (BD) will be reviewed, emphasising the findings in the phases of mania, hypomania and depression. Methods: It is a narrative review of the literature in which articles were searched in PubMed and Embase, with the key words in English "bipolar disorder" AND "resting state", without limit on the date of publication. Results: The studies of BD patients in the mania and hypomania phases who underwent R-fMRI show concordant results in terms of decreased functional cerebral connectivity between the amygdala and some cortical regions, which indicates that this functional connection would have some implication in the normal affect regulation. Patients in the depressive phase show a decrease in functional brain connectivity, but as there are seve-ral anatomical structures involved and neural networks reported in the studies, it is not possible to compare them. Conclusions: There is a decrease in functional connectivity in patients with BD, but current evidence does not allow establishing specific changes in specific functional brain connectivity networks. However, there are already some findings that show correlation with the patients' symptoms.