PIN-FORMED is required for shoot phototropism/gravitropism and facilitates meristem formation in Marchantia polymorpha.

PIN-FORMED auxin efflux transporters, a subclass of which is plasma membrane-localised, mediate a variety of land-plant developmental processes via their polar localisation and subsequent directional auxin transport. We provide the first characterisation of PIN proteins in liverworts using Marchantia polymorpha as a model system. Marchantia polymorpha possesses a single PIN-FORMED gene, whose protein product is predicted to be plasma membrane-localised, MpPIN1. To characterise MpPIN1, we created loss-of-function alleles and produced complementation lines in both M. polymorpha and Arabidopsis. In M. polymorpha, gene expression and protein localisation were tracked using an MpPIN1 transgene encoding a translationally fused fluorescent protein. Overexpression of MpPIN1 can partially complement loss of an orthologous gene, PIN-FORMED1, in Arabidopsis. In M. polymorpha, MpPIN1 influences development in numerous ways throughout its life cycle. Most notably, MpPIN1 is required to establish gemmaling dorsiventral polarity and for orthotropic growth of gametangiophore stalks, where MpPIN1 is basally polarised. PIN activity is largely conserved within land plants, with PIN-mediated auxin flow providing a flexible mechanism to organise growth. Specifically, PIN is fundamentally linked to orthotropism and to the establishment of de novo meristems, the latter potentially involving the formation of both auxin biosynthesis maxima and auxin-signalling minima.

Solanum lycopersicum CLASS-II KNOX genes regulate fruit anatomy via gibberellin-dependent and independent pathways.

The pericarp is the predominant tissue determining the structural characteristics of most fruits. However, the molecular and genetic mechanisms controlling pericarp development remain only partially understood. Previous studies have identified that CLASS-II KNOX genes regulate fruit size, shape, and maturation in Arabidopsis thaliana and Solanum lycopersicum. Here we characterized the roles of the S. lycopersicum CLASS-II KNOX (TKN-II) genes in pericarp development via a detailed histological, anatomical, and karyotypical analysis of TKN-II gene clade mRNA-knockdown (35S:amiR-TKN-II) fruits. We identify that 35S:amiR-TKN-II pericarps contain more cells around their equatorial perimeter and fewer cell layers than the control. In addition, the cell sizes but not the ploidy levels of these pericarps were dramatically reduced. Further, we demonstrate that fruit shape and pericarp layer number phenotypes of the 35S:amiR-TKN-II fruits can be overridden by the procera mutant, known to induce a constitutive response to the plant hormone gibberellin. However, neither the procera mutation nor exogenous gibberellin application can fully rescue the reduced pericarp width and cell size phenotype of 35S:amiR-TKN-II pericarps. Our findings establish that TKN-II genes regulate tomato fruit anatomy, acting via gibberellin to control fruit shape but utilizing a gibberellin-independent pathway to control the size of pericarp cells.

Espectro clínico de la Encefalitis Autoinmune no NMDAR en pediatría

En este trabajo se realizó una revisión narrativa de los principales hallazgos en la literatura médica sobre las manifestaciones clínicas de la encefalitis autoinmune pediátrica (EAP) no mediada por anticuerpos anti receptor del ácido N-metil-D-aspartato (NMDAR). Las EAP que se destacaron se asocian con anticuerpos específicos como el complejo de canales de potasio dependiente de voltaje, la decarboxilasa del ácido glutámico, el receptor del ácido alfa-amino-3-hidroxi-5-metil-4-isoxazolpropiónico y el receptor ácido-gamma-aminobutírico. El diagnóstico de esta patología es un desafío en pediatría debido a la complejidad de las manifestaciones psiquiátricas y neurológicas generadas por la afectación de la corteza, el sistema límbico, el tallo cerebral, los ganglios basales y el cerebelo. A su vez, la comprensión de sus síntomas permite identificar la superposición en las presentaciones clínicas entre los diferentes tipos de EAP y el diagnóstico diferencial con otras enfermedades inflamatorias del cerebro, infecciones, enfermedades metabólicas y trastornos psiquiátricos. El conocimiento biomédico y la sospecha clínica de las EAP no NMDAR establece un campo de investigación que crece en neuropsiquiatría y favorece el diagnóstico y tratamiento de las encefalitis subdiagnosticadas.

This work presents a narrative review of the main findings in the medical literature on the clinical manifestations of pediatric autoimmune encephalitis (PAE) not mediated by anti-N-methyl-Daspartate acid receptor (NMDAR) antibodies. Prominent PAEs are associated with specific antibodies, such as the voltage-gated potassium channel complex, glutamic acid decarboxylase, alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor, and alpha-amino -3-hydroxy-5. -methyl-4-isoxazolepropionic acid receptor. -gamma-aminobutyric. Diagnosis of this pathology is a challenge in pediatrics due to the complexity of psychiatric and neurological manifestations generated by involvement of cortex, limbic system, brainstem, basal ganglia and cerebellum. In turn, understanding its symptoms allows identifying the overlap in clinical presentations between the different types of PAE and the differential diagnosis with other inflammatory diseases of the brain, infections, metabolic diseases and psychiatric disorders. Biomedical knowledge and clinical suspicion of non-NMDAR PAE establishes a growing field of research in neuropsychiatry and favors the diagnosis and treatment of underdiagnosed encephalitides.

Factores asociados con el tiempo de progresión de la discapacidad en pacientes con esclerosis múltiple / Factors associated with time to disability progression in patients with multiple sclerosis

Objetivos. Determinar los factores sociodemográficos, clínicos y radiológicos asociados al tiempo de progresión de discapacidad en pacientes con esclerosis múltiple (EM). Materiales y métodos. Estudio transversal analítico, basado en registros de la historia clínica de pacientes del Instituto Neurológico de Colombia, entre el 2013 y 2021. La progresión a discapacidad de los pacientes con EM se definió como el tiempo hasta un aumento de por lo menos 0,5 puntos en el valor de la EDSS (del inglés Expanded Disability Status Scale), sostenido por al menos seis meses. Se usó un modelo de regresión de Cox para estimar la función de supervivencia y los hazard ratios (HR) con sus intervalos de confianza de 95% (IC 95%). Resultados. Se incluyeron 216 pacientes, de los cuales el 25% progresó a discapacidad, la mediana de supervivencia fue de 78 meses (RIC 95%: 70−83), las lesiones activas (HR = 1,94; IC 95%: 1,10−3,44), el sexo masculino (HR = 2,5; IC 95%: 1,32−4,73), y las enfermedades neurológicas (HR = 2,18; IC95%: 1,03−4,61) se asociaron en el modelo multivariado. Conclusiones. La mediana de tiempo de progresión hacia la discapacidad fue de 72 meses. Las lesiones activas captadas en resonancia magnética y el sexo masculino se asociaron con mayor progresión de la discapacidad, con resultados estadísticamente significativos en el modelo multivariado.

Objectives. To determine the sociodemographic, clinical and radiological factors associated with time to disability progression in patients with multiple sclerosis (MS). Materials and methods. Cross-sectional descriptive study with an analytical component, based on clinical records of patients at the Neurological Institute of Colombia, between 2013 and 2021. Progression to disability in MS patients was defined as the time to an increase of at least 0.5 points in the EDSS (Expanded Disability Status Scale) score, sustained for at least six months. A Cox regression model was used to estimate the survival function and Hazard Ratios (HR) with their 95% confidence intervals (95% CI). Results. We included 216 patients, of whom 25% progressed to disability, median survival was 78 months (95% CI: 70-83), active lesions (HR = 1.94; 95% CI: 1.10-3.44), cerebellar complications (HR = 2.03; 95% CI: 0. 99-4.16), being male (HR = 2.5; 95% CI: 1.32-4.73), and having neurological diseases (HR = 2.18; 95% CI: 1.03-4.61) were associated as risk factors. While relapsing remitting MS (HR = 0.63; 95% CI: 0.31-1.26) and age at diagnosis less than 40 years (HR = 0.96; 95% CI: 0.53-1.76) were associated as protective factors. Conclusions. Progression is affected by many factors, and there is no single independent factor.

CLASS-II KNOX genes coordinate spatial and temporal ripening in tomato.

Fruits can be divided into dry and fleshy types. Dry fruits mature through senescence and fleshy fruits through ripening. Previous studies have indicated that partially common molecular networks could govern fruit maturation in these different fruit types. However, the nature of such networks remains obscure. CLASS-II KNOX genes were shown to regulate the senescence of the Arabidopsis (Arabidopsis thaliana) dry fruits, the siliques, but their roles in fleshy-fruit development are unknown. Here, we investigated the roles of the tomato (Solanum lycopersicum) CLASS-II KNOX (TKN-II) genes in fleshy fruit ripening using knockout alleles of individual genes and an artificial microRNA line (35S:amiR-TKN-II) simultaneously targeting all genes. 35S:amiR-TKN-II plants, as well as a subset of tkn-II single and double mutants, have smaller fruits. Strikingly, the 35S:amiR-TKN-II and tknII3 tknII7/+ fruits showed early ripening of the locular domain while their pericarp ripening was stalled. Further examination of the ripening marker-gene RIPENING INHIBITOR (RIN) expression and 35S:amiR-TKN-II rin-1 mutant fruits suggested that TKN-II genes arrest RIN activity at the locular domain and promote it in the pericarp. These findings imply that CLASS-II KNOX genes redundantly coordinate maturation in both dry and fleshy fruits. In tomato, these genes also control spatial patterns of fruit ripening, utilizing differential regulation of RIN activity at different fruit domains.

Arousal elevation drives the development of oscillatory vocal output.

Adult behaviors, such as vocal production, often exhibit temporal regularity. In contrast, their immature forms are more irregular. We ask whether the coupling of motor behaviors with arousal changes gives rise to temporal regularity: Do they drive the transition from variable to regular motor output over the course of development? We used marmoset monkey vocal production to explore this putative influence of arousal on the nonlinear changes in their developing vocal output patterns. Based on a detailed analysis of vocal and arousal dynamics in marmosets, we put forth a general model incorporating arousal and auditory feedback loops for spontaneous vocal production. Using this model, we show that a stable oscillation can emerge as the baseline arousal increases, predicting the transition from stochastic to periodic oscillations observed during marmoset vocal development. We further provide a solution for how this model can explain vocal development as the joint consequence of energetic growth and social feedback. Together, we put forth a plausible mechanism for the development of arousal-mediated adaptive behavior.NEW & NOTEWORTHY The development of motor behaviors, and the influence of energetic and social factors on it, has long been of interest, yet we lack an integrated picture of how these different systems may interact. Through the lens of vocal development in infant marmosets, this study offers a solution for social behavior development by linking motor production with arousal states. Increases in arousal can drive the system out of stochastic states toward oscillatory dynamics ready for communication.

Neurodegeneration and convergent factors contributing to the deterioration of the cytoskeleton in Alzheimer's disease, cerebral ischemia and multiple sclerosis (Review).

The cytoskeleton is the main intracellular structure that determines the morphology of neurons and maintains their integrity. Therefore, disruption of its structure and function may underlie several neurodegenerative diseases. This review summarizes the current literature on the tau protein, microtubule-associated protein 2 (MAP2) and neurofilaments as common denominators in pathological conditions such as Alzheimer's disease (AD), cerebral ischemia, and multiple sclerosis (MS). Insights obtained from experimental models using biochemical and immunocytochemical techniques highlight that changes in these proteins may be potentially used as protein targets in clinical settings, which provides novel opportunities for the detection, monitoring and treatment of patients with these neurodegenerative diseases.

KANADI promotes thallus differentiation and FR-induced gametangiophore formation in the liverwort Marchantia.

In angiosperms, KANADI transcription factors have roles in the sporophyte generation regulating tissue polarity, organogenesis and shade avoidance responses, but are not required during the gametophyte generation. Whether these roles are conserved in the gametophyte-dominant bryophyte lineages is unknown, which we examined by characterising the sole KANADI ortholog, MpKAN, in the liverwort Marchantia polymorpha. In contrast to angiosperm orthologs, MpKAN functions in the gametophyte generation in Marchantia, where it regulates apical branching and tissue differentiation, but does not influence tissue polarity in either generation. MpKAN can partially rescue the sporophyte polarity defects of kanadi mutants in Arabidopsis, indicating that MpKAN has conserved biochemical activity to its angiosperm counterparts. Mpkan loss-of-function plants display defects in far-red (FR) light responses. Mpkan plants have reduced FR-induced growth tropisms, have a delayed transition to sexual reproduction and fail to correctly form gametangiophores. Our results indicate that MpKAN is a modulator of FR responses, which may reflect a conserved role for KANADI across land plants. Under FR, MpKAN negatively regulates MpDELLA expression, suggesting that MpKAN and MpDELLA act in a pathway regulating FR responses, placing MpKAN in a gene regulatory network exhibiting similarities with those of angiosperms.

Factors associated with time to disability progression in patients with multiple sclerosis. / Factores asociados con el tiempo de progresión de la discapacidad en pacientes con esclerosis múltiple.

OBJECTIVES.: Motivation for the study: multiple sclerosis (MS) is a complex disease that requires management by different disciplines. Data on Latin American patients is scarce, therefore, the usually used theoretical references are from other population groups. Main findings: sociodemographic (male), clinical (concomitant neurological diseases) and radiological (active lesions in magnetic resonance imaging) factors were found to be associated with disease progression. Implications: taking the above into account when approaching patients in daily clinical practice, it is possible to identify when their condition has greater possibilities of progression and thus eventually prevent complications. To determine the sociodemographic, clinical and radiological factors associated with time to disability progression in patients with multiple sclerosis (MS). MATERIALS AND METHODS.: Cross-sectional descriptive study with an analytical component, based on clinical records of patients at the Neurological Institute of Colombia, between 2013 and 2021. Progression to disability in MS patients was defined as the time to an increase of at least 0.5 points in the EDSS (Expanded Disability Status Scale) score, sustained for at least six months. A Cox regression model was used to estimate the survival function and Hazard Ratios (HR) with their 95% confidence intervals (95% CI). RESULTS.: We included 216 patients, of whom 25% progressed to disability, median survival was 78 months (95% CI: 70-83), active lesions (HR = 1.94; 95% CI: 1.10-3.44), cerebellar complications (HR = 2.03; 95% CI: 0. 99-4.16), being male (HR = 2.5; 95% CI: 1.32-4.73), and having neurological diseases (HR = 2.18; 95% CI: 1.03-4.61) were associated as risk factors. While relapsing remitting MS (HR = 0.63; 95% CI: 0.31-1.26) and age at diagnosis less than 40 years (HR = 0.96; 95% CI: 0.53-1.76) were associated as protective factors. CONCLUSIONS.: Progression is affected by many factors, and there is no single independent factor.

OBJETIVOS.: Motivación para realizar el estudio: la esclerosis múltiple (EM) es una enfermedad compleja que requiere manejo por diferentes disciplinas, en la literatura científica existen pocos datos de pacientes latinoamericanos, por ende, los referentes teóricos son de otros grupos poblacionales. Principales hallazgos: se encontró que factores sociodemográficos (sexo masculino), clínicos (enfermedades neurológicas concomitantes) y radiológicos (lesiones activas captadas en resonancia magnética) se asociaron con la progresión de la enfermedad. Implicancias: teniendo en cuenta lo anterior al momento de abordar los pacientes en la práctica clínica diaria, se puede clasificar su condición con mayores posibilidades de progresión y así eventualmente prevenir complicaciones. Determinar los factores sociodemográficos, clínicos y radiológicos asociados al tiempo de progresión de discapacidad en pacientes con esclerosis múltiple (EM). MATERIALES Y MÉTODOS.: Estudio transversal analítico, basado en registros de la historia clínica de pacientes del Instituto Neurológico de Colombia, entre el 2013 y 2021. La progresión a discapacidad de los pacientes con EM se definió como el tiempo hasta un aumento de por lo menos 0,5 puntos en el valor de la EDSS (del inglés Expanded Disability Status Scale), sostenido por al menos seis meses. Se usó un modelo de regresión de Cox para estimar la función de supervivencia y los hazard ratios (HR) con sus intervalos de confianza de 95% (IC 95%). RESULTADOS.: Se incluyeron 216 pacientes, de los cuales el 25% progresó a discapacidad, la mediana de supervivencia fue de 78 meses (RIC 95%: 70−83), las lesiones activas (HR = 1,94; IC 95%: 1,10−3,44), el sexo masculino (HR = 2,5; IC 95%: 1,32−4,73), y las enfermedades neurológicas (HR = 2,18; IC95%: 1,03−4,61) se asociaron en el modelo multivariado. CONCLUSIONES.: La mediana de tiempo de progresión hacia la discapacidad fue de 72 meses. Las lesiones activas captadas en resonancia magnética y el sexo masculino se asociaron con mayor progresión de la discapacidad, con resultados estadísticamente significativos en el modelo multivariado.

Circulating tumor DNA for comprehensive noninvasive monitoring of lymphoma treated with ibrutinib plus nivolumab.

To advance the use of circulating tumor DNA (ctDNA) applications, their broad clinical validity must be tested in different treatment settings, including targeted therapies. Using the prespecified longitudinal systematic collection of plasma samples in the phase 1/2a LYM1002 trial (registered on www.clinicaltrials.gov as NCT02329847), we tested the clinical validity of ctDNA for baseline mutation profiling, residual tumor load quantification, and acquisition of resistance mutations in patients with lymphoma treated with ibrutinib+nivolumab. Inclusion criterion for this ancillary biological study was the availability of blood collected at baseline and cycle 3, day 1. Overall, 172 ctDNA samples from 67 patients were analyzed by the LyV4.0 ctDNA Cancer Personalized Profiling Deep Sequencing Assay. Among baseline variants in ctDNA, only TP53 mutations (detected in 25.4% of patients) were associated with shorter progression-free survival; clones harboring baseline TP53 mutations did not disappear during treatment. Molecular response, defined as a >2-log reduction in ctDNA levels after 2 cycles of therapy (28 days), was achieved in 28.6% of patients with relapsed diffuse large B-cell lymphoma who had ≥1 baseline variant and was associated with best response and improved progression-free survival. Clonal evolution occurred frequently during treatment, and 10.3% new mutations were identified after 2 treatment cycles in nonresponders. PLCG2 was the topmost among genes that acquired new mutations. No patients acquired the C481S BTK mutation implicated in resistance to ibrutinib in CLL. Collectively, our results provide the proof of concept that ctDNA is useful for noninvasive monitoring of lymphoma treated with targeted agents in the clinical trial setting.

Biomarkers of response to ibrutinib plus nivolumab in relapsed diffuse large B-cell lymphoma, follicular lymphoma, or Richter's transformation.

We analyzed potential biomarkers of response to ibrutinib plus nivolumab in biopsies from patients with diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL), and Richter's transformation (RT) from the LYM1002 phase I/IIa study, using programmed death ligand 1 (PD-L1) immunohistochemistry, whole exome sequencing (WES), and gene expression profiling (GEP). In DLBCL, PD-L1 elevation was more frequent in responders versus nonresponders (5/8 [62.5%] vs. 3/16 [18.8%]; p = 0.065; complete response 37.5% vs. 0%; p = 0.028). Overall response rates for patients with WES and GEP data, respectively, were: DLBCL (38.5% and 29.6%); FL (46.2% and 43.5%); RT (76.5% and 81.3%). In DLBCL, WES analyses demonstrated that mutations in RNF213 (40.0% vs. 6.2%; p = 0.055), KLHL14 (30.0% vs. 0%; p = 0.046), and LRP1B (30.0% vs. 6.2%; p = 0.264) were more frequent in responders. No responders had mutations in EBF1, ADAMTS20, AKAP9, TP53, MYD88, or TNFRSF14, while the frequency of these mutations in nonresponders ranged from 12.5% to 18.8%. In FL and RT, genes with different mutation frequencies in responders versus nonresponders were: BCL2 (75.0% vs. 28.6%; p = 0.047) and ROS1 (0% vs. 50.0%; p = 0.044), respectively. Per GEP, the most upregulated genes in responders were LEF1 and BTLA (overall), and CRTAM (germinal center B-cell-like DLBCL). Enriched pathways were related to immune activation in responders and resistance-associated proliferation/replication in nonresponders. This preliminary work may help to generate hypotheses regarding genetically defined subsets of DLBCL, FL, and RT patients most likely to benefit from ibrutinib plus nivolumab.

Medicamentos modificadores en esclerosis múltiple: esquemas terapéuticos actuales / Disease-Modifying drugs in multiple sclerosis: current therapeutic schemes

La esclerosis múltiple (EM) es una enfermedad crónica, autoinmune y neurodegenerativa; que tiene como principal característica la desmielinización de los axones en el sistema nervioso. Los medicamentos modificadores de la enfermedad (MME) logran retrasar la aparición de los síntomas y modificar parcialmente el progreso de la desmielinización y daño neuronal, resultando cada vez más complejo determinar un esquema terapéutico estandarizado según la condición particular de cada paciente. En este artículo se presenta una revisión actualizada de la evidencia clínica que ha llevado al uso de los esquemas terapéuticos en EM. La mayoría de los medicamentos aprobados actualmente son utilizados para la EM remitente-recurrente y se pueden dividir de acuerdo a la eficacia y seguridad. Los medicamentos de primera línea han mostrado una baja o moderada eficacia y alta seguridad; después de usar estos fármacos sin lograr una buena respuesta o ante una enfermedad avanzada se usan medicamentos de segunda y tercera línea que tienen una alta eficacia, pero son menos seguros, presentando mayores efectos secundarios y riesgos asociados para los pacientes. El ocrelizumab es el único fármaco aceptado para la EM primaria progresiva y el siponimod fue aprobado como una alternativa para la EM secundaria progresiva. El desarrollo de nuevos medicamentos y el seguimiento clínico de los ya aprobados permitirá establecer un mejor abordaje terapéutico logrando así mejorar la calidad de vida de cada paciente.

Multiple sclerosis (MS) is a chronic, autoimmune and neurodegenerative disease; whose main characteristic is the demyelination of axons in the nervous system. Disease-modifying drugs (DMD) can delay the onset of symptoms and partially modify the progression of demyelination and neuronal damage, making it increasingly complex to determine a standardized therapeutic scheme that is individualized to each patient. This article presents an updated review on the clinical evidence that has led to the use of current therapeutic schemes in MS with focus on DMD. Current medications in treating relapsing-remitting MS can be divided according to efficacy and safety. First-line drugs have shown low or moderate efficacy and high safety. Second- and third-line drugs are used after a poor response or in cases of advanced disease. These drugs are highly effective, but less safe, presenting greater side effects and associated risks for patients. Ocrelizumab is the only accepted drug for primary progressive MS and siponimod is accepted as an alternative for secondary progressive MS. The development of new medications and the clinical follow-up of those already approved will allow establishing a better therapeutic approach, thus improving the quality of life of each patient.

Traumatismo craneoencefálico en niños. Hospital General de Medellín y Clínica Somer de Rionegro, 2010-2017 / Pediatric Traumatic Brain Injury. Hospital General of Medellin and Clínica Somer of Rionegro, 2010- 2017

RESUMEN Objetivo: describir las características sociodemográficas, aspectos clínicos y complicaciones de los niños de 0 a 10 años de edad que sufrieron traumatismo craneoencefálico, atendidos en el Hospital General de Medellín y en la Clínica Somer de Rionegro entre los años 2010 y 2017. Métodos: estudio descriptivo retrospectivo, toma como fuente de información las historias clínicas de los niños con diagnósticos relacionados con el traumatismo craneoencefálico entre 2010-2017. Se calcularon las proporciones de las variables sociodemográficas, circunstanciales, espacio-temporales y clínicas. Resultados: se encontraron 224 pacientes con traumatismo craneoencefálico, el 64,7 % de los casos fueron de sexo masculino, la edad promedio fue de 4,5 años. El trauma ocurrió con mayor frecuencia en el domicilio del paciente entre los días de la semana en las horas de la tarde. La causa principal del trauma fue caída (75 %), seguido por accidentes de tránsito (13,3 %). La gravedad del traumatismo se midió con la escala de coma de Glasgow, el 78 % fue leve, hubo un caso fatal y 7 (3 %) tuvieron complicaciones motoras durante la hospitalización. Conclusión: los hallazgos de este estudio coinciden con las principales características del traumatismo craneoencefálico de la población pediátrica en el mundo, amplía la información regional y local para el desarrollo de estrategias de prevención, diagnóstico y seguimiento a largo plazo de los pacientes.

SUMMARY Objective: To describe the demography, clinical presentation and complications associated with traumatic brain injury (TBI) in a cohort of children, ages 0-10, treated at Hospital General de Medellín and Clínica Somer between 2010-2017. Methods: Cross sectional retrospective study chart review of all children with a diagnosis of TBI between 2010 and 2017. There were systematic review and recording of demographic information, mechanism of injury, clinical presentation, and associated complications. Results: A total of 224 patients with TBI were identified. Among them, 64.7% were males and mean age was 4.5 years. Injuries most frequently occurred at the patient's home, during the afternoon hours and between Monday and Friday. The most common mechanisms of injury were falls (75%), followed by motor vehicle accidents (13.3%). Severity of injury, measured by Glasgow coma scale, found that 78% of cases were mild. Seven (3%) of cases had neuromuscular complications during hospitalization and one TBI related death was identified. Conclusion: Findings of this study are consistent with the known characteristics of pediatric TBI worldwide. This information may be used to improve prevention, diagnosis, and long term follow-up.

Identificación de Helicobacter pylori por medio de la coloración especial de Warthin-Starry en biopsias de pacientes con gastritis crónica folicular, previamente negativas en la tinción de hematoxilina-eosina / Warthin-Starry stain identification of Helicobacter pylori in biopsies of patients who previously tested negative in hematoxylin-eosin staining for follicular gastritis

Resumen Las técnicas empleadas para la detección del Helicobacter pylori (H. pylori) son no invasivas e invasivas. En estas últimas, la presencia del H. pylori se determina a partir de la tinción de hematoxilina-eosina (HE), prueba rutinaria, mientras que en pocas ocasiones se aplica la tinción de Warthin-Starry (WS) como coloración especial. Objetivo: identificar la presencia de H. pylori por medio de la coloración especial de la WS en biopsias de pacientes con gastritis crónica folicular, previamente negativas en la tinción HE. Materiales y métodos: se desarrolló un estudio de tipo descriptivo transversal, en un período de 12 meses. Se tomaron los bloques de parafina de las muestras de la mucosa gástrica de pacientes con diagnóstico de gastritis crónica e hiperplasia folicular. Además, se extrajo un corte histológico del mismo bloque, al cual se le aplicó HE y se determinó la presencia o ausencia de H. pylori. Así, de estar ausente, se tomó del mismo bloque un corte adicional y se aplicó WS. Esto se evaluó con el fin de identificar la existencia o no del bacilo. Resultados: se recolectaron 314 muestras; 209 fueron negativas y 105 fueron positivas para HE. El 45 % (94) de estas muestras fueron positivas respecto a la presencia del bacilo, al aplicar la segunda coloración, y el 55 % (115) de las muestras persistieron negativas. Conclusión: el hallazgo de H. pylori es significativamente alto al aplicar la coloración de WS a muestras cuyo estudio histológico evidenció la ausencia del bacilo en biopsias de la mucosa gástrica, especialmente en muestras con escasa cantidad de bacterias.

Abstract Non-invasive and invasive techniques can be used for detection of Helicobacter pylori. An invasive technique identifies the bacteria through routine hematoxylin-eosin staining. Warthin-Starry stain is rarely used. Objective: Our objective was to identify H. pylori by Warthin-Starry staining of patient's biopsies with chronic follicular gastritis who had previously tested negative in hematoxylin-eosin staining. Materials and methods: This is a descriptive, cross-sectional descriptive study that was carried out over a period of 12 months. The study examined paraffin blocks of samples taken from the gastric mucosa of patients diagnosed with chronic gastritis and follicular hyperplasia. A histological section was extracted from a block and tested with hematoxylin-eosin staining for the presence or absence of H. pylori. If absent, an additional cut was taken from the same block and Warthin-Starry staining was used to retest for the presence of the bacteria. Results: Of the 314 samples collected, 209 tested negative, and 105 tested positive for H. pylori when hematoxylin-eosin staining was used. Of the 209 negative samples, 45% (94) tested positive when Warthin Starry stain was used, and 55% (115) still tested negative. Conclusion: Findings of H. pylori are significantly higher when Warthin Starry stain was used to test samples whose previous histological study had evidenced an absence of the bacillus, especially in samples with a small amount of bacteria.

Corioangioma placentario: reporte de un caso en la Unidad de Patología del Hospital San Juan de Dios E.S.E. Rionegro-Antioquia / Placental chorioangioma: case report in the Pathology Unit of the San Juan de Dios E.S.E. Hospital in Rionegro-Antioquia

Dentro de las neoplasias no trofoblásticas gestacionales de tipo vascular, el corioangioma es la más común. Se caracteriza por presentar una proliferación exagerada de estructuras vasculares, con células endoteliales y vellosidades coriónicas que generan una alteración de los vasos sanguíneos tanto arteriales como venosos. Tiene una incidencia menor al 1%, con tasas de mortalidad perinatal aproximadas entre 18% a 40%. Se presenta el caso de un corioangioma placentario diagnosticado a las 26 semanas de gestación en una paciente de 21 años de edad sin controles prenatales previos, el cual generó un lóbulo accesorio de 7 cm con tinción positiva en el análisis inmunohistoquímico para anticuerpos antimúsculo liso y CD34, y negativa para Ki67. El corioangioma desencadenó complicaciones en el embarazo, con parto pretérmino, hidropesía fetal y retardo en el crecimiento intrauterino, que llevaron a la muerte fetal. La falta de control prenatal en nuestra paciente impidió que se detectaran las anomalías placentarias oportunamente, con un desenlace fatal para el feto. Un control prenatal adecuado con seguimiento ecográfico puede evitar eventos fatales como el presentado. El análisis macroscópico y microscópico de la placenta puede favorecer la identificación de los casos y el aporte a las estadísticas de incidencia y mortalidad.

Among vascular gestational nontrophoblastic tumors, chorioangioma is the most common. It is characterized by an exaggerated proliferation of vascular structures, with endothelial cells and chorionic villi that generate abnormalities of both arterial and venous blood vessels. It has an incidence of less than 1%, with perinatal mortality rates between 18% to 40%. We present the case of a 21-year-old patient without previous prenatal controls, with a placental chorioangioma diagnosed at 26 weeks of gestation that formed a 7 cm accessory lobe, with positive staining during immunohistochemical analysis for smooth anti-muscle antibodies and CD34, and negative for Ki67. The placental chorioangioma triggered complications during pregnancy, with preterm delivery, hydrops fetalis, and intrauterine growth retardation leading to fetal death. The lack of prenatal control in our patient prevented an early detection of placental abnormalities with a fatal outcome for the fetus. Adequate prenatal control with ultrasound monitoring can avoid fatal events such as the one presented. Macroscopic and microscopic analysis of the placenta can help identify cases and contribute to incidence and mortality statistics.

Sarcoma de Ewing extraóseo en la columna dorsal con compresión medular al momento del diagnóstico: Reporte de un caso / Primary extra-osseous Ewing sarcoma of the dorsal spine with spinal cord compression at diagnosis: Case report

Los tumores neuroectodérmicos primitivos a nivel extraóseo son una neoplasia muy rara, con pocas publicaciones en la literatura. Se reporta un caso de una paciente de nueve años quien se presentó con signos de compresión medular. Se estableció un grupo de diagnósticos diferenciales en el abordaje, entre los que debió incluirse la patología oncológica. En la paciente, se observó la presencia de una masa en la columna dorsal con compromiso del cordón medular, que requirió cirugía descompresiva de urgencia y, posteriormente, se diagnosticó sarcoma de Ewing. Cabe resaltar la importancia del caso debido a la baja incidencia del origen extraóseo en esta neoplasia y su rara localización en la columna dorsal, y destacar la presencia de la compresión medular como forma de presentación del cáncer en pediatría, además de la poca información que, hasta el momento, se posee referida al mejor abordaje terapéutico en esta patología, en esta localización.

Extraosseous primitive neuroectodermal tumors are very rare neoplasms. Only a few cases have been published in the literature. This report is about a 9-year-old female patient whose clinical manifestations showed spinal cord compression, so different diagnosis should be considered, including oncology disease. The patient showed a mass of the dorsal spine with spinal cord compression. She was diagnosed with Ewing Sarcoma after surgical intervention and pathology study. It is necessary to highlight the importance of the present case due to the low incidence of the extraosseous Ewing Sarcoma, and its infrequent location at the dorsal spine and the spinal cord compression as initial presentation of pediatric cancer, as well as the poor information related to the best therapeutic strategy to treat this disease at this location.