Calcineurin-Dependent Homeostatic Response of C. elegans Muscle Cells upon Prolonged Activation of Acetylcholine Receptors.

Pharmacological adaptation is a common phenomenon observed during prolonged drug exposure and often leads to drug resistance. Understanding the cellular events involved in adaptation could provide new strategies to circumvent this resistance issue. We used the nematode Caenorhabditis elegans to analyze the adaptation to levamisole, an ionotropic acetylcholine receptor agonist, used for decades to treat nematode parasitic infections. Genetic screens in C. elegans identified "adapting mutants" that initially paralyze upon exposure to levamisole as the wild type (WT), but recover locomotion after a few hours whereas WT remain paralyzed. Here, we show that levamisole induces a sustained increase in cytosolic calcium concentration in the muscle cells of adapting mutants, lasting several hours and preceding a decrease in levamisole-sensitive acetylcholine receptors (L-AChR) at the muscle plasma membrane. This decrease correlated with a drop in calcium concentration, a relaxation of the animal's body and a resumption of locomotion. The decrease in calcium and L-AChR content depends on calcineurin activation in muscle cells. We also showed that levamisole adaptation triggers homeostatic mechanisms in muscle cells including mitochondria remodeling, lysosomal tubulation and an increase in autophagic activity. Levamisole adaptation thus provides a new experimental paradigm for studying how cells cope with calcium stress.

A genotype-to-phenotype approach suggests under-reporting of single nucleotide variants in nephrocystin-1 (NPHP1) related disease (UK 100,000 Genomes Project).

Autosomal recessive whole gene deletions of nephrocystin-1 (NPHP1) result in abnormal structure and function of the primary cilia. These deletions can result in a tubulointerstitial kidney disease known as nephronophthisis and retinal (Senior-Løken syndrome) and neurological (Joubert syndrome) diseases. Nephronophthisis is a common cause of end-stage kidney disease (ESKD) in children and up to 1% of adult onset ESKD. Single nucleotide variants (SNVs) and small insertions and deletions (Indels) have been less well characterised. We used a gene pathogenicity scoring system (GenePy) and a genotype-to-phenotype approach on individuals recruited to the UK Genomics England (GEL) 100,000 Genomes Project (100kGP) (n = 78,050). This approach identified all participants with NPHP1-related diseases reported by NHS Genomics Medical Centres and an additional eight participants. Extreme NPHP1 gene scores, often underpinned by clear recessive inheritance, were observed in patients from diverse recruitment categories, including cancer, suggesting the possibility of a more widespread disease than previously appreciated. In total, ten participants had homozygous CNV deletions with eight homozygous or compound heterozygous with SNVs. Our data also reveals strong in-silico evidence that approximately 44% of NPHP1 related disease may be due to SNVs with AlphaFold structural modelling evidence for a significant impact on protein structure. This study suggests historical under-reporting of SNVS in NPHP1 related diseases compared with CNVs.

Repurposing small molecules for nephronophthisis and related renal ciliopathies.

Nephronophthisis is an autosomal recessive tubulointerstitial nephropathy, belonging to the ciliopathy disorders, characterized by fibrosis and/or cysts. It is the most common genetic cause of kidney failure in children and young adults. Clinically and genetically heterogeneous, it is caused by variants in ciliary genes, resulting in either an isolated kidney disease or syndromic forms in association with other manifestations of ciliopathy disorders. No curative treatment is currently available. Over the past 2 decades, advances in understanding disease mechanisms have identified several dysregulated signaling pathways, some shared with other cystic kidney diseases. Notably, molecules previously developed to target these pathways have shown promising beneficial effects in orthologous mouse models. In addition to these knowledge-based repurposing approaches, unbiased "in cellulo" phenotypic screens of "repurposing" libraries identified small molecules able to rescue the ciliogenesis defects observed in nephronophthisis conditions. Those compounds appeared to act on relevant pathways and, when tested, showed beneficial nephronophthisis-associated kidney and/or extrarenal defects in mice. In this review, we have summarized those studies that highlight the drug repurposing strategies in the context of a rare disorders, such as nephronophthisis-related ciliopathies, with broad genetic heterogeneity and systemic manifestations but with shared disease mechanisms.

Agonists of prostaglandin E2 receptors as potential first in class treatment for nephronophthisis and related ciliopathies.

Nephronophthisis (NPH) is an autosomal recessive tubulointerstitial nephropathy belonging to the ciliopathy disorders and known as the most common cause of hereditary end-stage renal disease in children. Yet, no curative treatment is available. The major gene, NPHP1, encodes a protein playing key functions at the primary cilium and cellular junctions. Using a medium-throughput drug-screen in NPHP1 knockdown cells, we identified 51 Food and Drug Administration-approved compounds by their ability to alleviate the cellular phenotypes associated with the loss of NPHP1; 11 compounds were further selected for their physicochemical properties. Among those compounds, prostaglandin E1 (PGE1) rescued ciliogenesis defects in immortalized patient NPHP1 urine-derived renal tubular cells, and improved ciliary and kidney phenotypes in our NPH zebrafish and Nphp1 knockout mouse models. Furthermore, Taprenepag, a nonprostanoid prostaglandin E2 receptor agonist, alleviated the severe retinopathy observed in Nphp1−/− mice. Finally, comparative transcriptomics allowed identification of key signaling pathways downstream PGE1, including cell cycle progression, extracellular matrix, adhesion, or actin cytoskeleton organization. In conclusion, using in vitro and in vivo models, we showed that prostaglandin E2 receptor agonists can ameliorate several of the pleotropic phenotypes caused by the absence of NPHP1; this opens their potential as a first therapeutic option for juvenile NPH-associated ciliopathies.

Patient-Patient Similarity-Based Screening of a Clinical Data Warehouse to Support Ciliopathy Diagnosis.

A timely diagnosis is a key challenge for many rare diseases. As an expanding group of rare and severe monogenic disorders with a broad spectrum of clinical manifestations, ciliopathies, notably renal ciliopathies, suffer from important underdiagnosis issues. Our objective is to develop an approach for screening large-scale clinical data warehouses and detecting patients with similar clinical manifestations to those from diagnosed ciliopathy patients. We expect that the top-ranked similar patients will benefit from genetic testing for an early diagnosis. The dependence and relatedness between phenotypes were taken into account in our similarity model through medical concept embedding. The relevance of each phenotype to each patient was also considered by adjusted aggregation of phenotype similarity into patient similarity. A ranking model based on the best-subtype-average similarity was proposed to address the phenotypic overlapping and heterogeneity of ciliopathies. Our results showed that using less than one-tenth of learning sources, our language and center specific embedding provided comparable or better performances than other existing medical concept embeddings. Combined with the best-subtype-average ranking model, our patient-patient similarity-based screening approach was demonstrated effective in two large scale unbalanced datasets containing approximately 10,000 and 60,000 controls with kidney manifestations in the clinical data warehouse (about 2 and 0.4% of prevalence, respectively). Our approach will offer the opportunity to identify candidate patients who could go through genetic testing for ciliopathy. Earlier diagnosis, before irreversible end-stage kidney disease, will enable these patients to benefit from appropriate follow-up and novel treatments that could alleviate kidney dysfunction.

Recomendaciones y consideraciones del Comité Vascular de la Asociación Colombiana de Neurología para el manejo del ataque cerebrovascular isquémico durante la pandemia por covid-19 / Considerations and recommendations from the Stroke Committee of the Colombian Neurological Association for the management of Acute Ischemic Stroke during the pandemic for COVID-19

RESUMEN PROPÓSITO: En marzo 11 del 2020 la Organización Mundial de la Salud declara la pandemia por Covid-19. El clínico se va enfrentar a pacientes con ataque cerebrovascular (ACV) y sospecha o presencia de la infección. Miembros participantes del comité vascular de la Asociación Colombiana de Neurología basados en la experticia y la literatura amplían las primeras recomendaciones en el manejo de los pacientes con ACV isquémico agudo durante la actual pandemia. MÉTODOS: Mediante reuniones virtuales y por consenso de los participantes se escogieron tres ejes de trabajo: Tamización para Covid-19, Medidas de bioseguridad y Aspectos relevantes del ACV isquémico en época de pandemia por Covid-19. Se desarrollaron los ejes por grupos de trabajo mediante la modalidad de pregunta-respuesta pretendiendo generar en cada una de ellas recomendaciones sobre el tema. La versión final del documento conto con la revisión y el aval de todos los participantes. RESULTADOS: El documento cuenta con tres secciones correspondientes a los ejes de trabajo. En el primer eje se responden 3 preguntas y se dan recomendaciones sobre la tamización de la infección por Covid-19 en ACV agudo. En el segundo se responden 8 preguntas y se dan recomendaciones sobre las medidas de bioseguridad en la atención de pacientes con ACV durante la pandemia. En el tercero se tratan 13 aspectos relevantes del ACV durante la pandemia, según criterio de los participantes, y se dan recomendaciones pertinentes. CONCLUSIÓN: Las recomendaciones son basadas en la literatura y consenso de los participantes para el cuidado de pacientes con ACV isquémico agudo con sospecha o infección por Covid-19. No pretenden reemplazar las guías o protocolos establecidos sino ampliar las primeras recomendaciones del comité y apoyar al clínico en la atención de pacientes con ACV isquémico durante la pandemia.

SUMMARY PURPOSE: The World Health Organization declared the COVID-19 pandemic on March 11th 2020. Clinicians will face patients with stroke and confirmed or suspected infection. Members of the Stroke Committee of the Colombian Neurological Association based on their expertise and literature review extend on the first recommendations on acute ischemic stroke management during the pandemic. METHODS: Through virtual meetings and by consensus of participants three topics were selected: COVID-19 screening, biosafety measures and relevant aspects of acute ischemic stroke care during the pandemic. A question and answer format was used to develop recommendations for each topic. RESULTS: The manuscript is divided into three sections. The first includes three questions and recommendations on screening for COVID-19 in stroke patients. The second includes 8 questions and recommendations on biosafety measures on stroke patients during the pandemic. The last section includes 13 relevant stroke topics during COVID-19 pandemic, as deemed by the authors, and their recommendations. CONCLUSIONS: Recommendations on stroke care and COVID-19 are based on literature review and expert consensus. The aim of the manuscript is to extend on the first recommendations forwarded by the Committee, not to replace current guidelines, and to support the clinician caring for stroke patients during the pandemic.

Author Correction: High-throughput single-cell activity-based screening and sequencing of antibodies using droplet microfluidics.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

High-throughput single-cell activity-based screening and sequencing of antibodies using droplet microfluidics.

Mining the antibody repertoire of plasma cells and plasmablasts could enable the discovery of useful antibodies for therapeutic or research purposes1. We present a method for high-throughput, single-cell screening of IgG-secreting primary cells to characterize antibody binding to soluble and membrane-bound antigens. CelliGO is a droplet microfluidics system that combines high-throughput screening for IgG activity, using fluorescence-based in-droplet single-cell bioassays2, with sequencing of paired antibody V genes, using in-droplet single-cell barcoded reverse transcription. We analyzed IgG repertoire diversity, clonal expansion and somatic hypermutation in cells from mice immunized with a vaccine target, a multifunctional enzyme or a membrane-bound cancer target. Immunization with these antigens yielded 100-1,000 IgG sequences per mouse. We generated 77 recombinant antibodies from the identified sequences and found that 93% recognized the soluble antigen and 14% the membrane antigen. The platform also allowed recovery of ~450-900 IgG sequences from ~2,200 IgG-secreting activated human memory B cells, activated ex vivo, demonstrating its versatility.

Sex Differences Among Participants in the Latin American Stroke Registry.

Background Reports on sex differences in stroke outcome and risk factors are scarce in Latin America. Our objective was to analyze clinical and prognostic differences according to sex among participants in the LASE (Latin American Stroke Registry). Methods and Results Nineteen centers across Central and South America compiled data on demographics, vascular risk factors, clinical stroke description, ancillary tests, and functional outcomes at short-term follow-up of patients included from January 2012 to January 2017. For the present study, all these variables were analyzed according to sex at hospital discharge. We included 4788 patients with a median in-hospital stay of 8 days (interquartile range, 5-8); 2677 were male (median age, 66 years) and 2111 female (median age, 60 years). Ischemic stroke occurred in 4293: 3686 as cerebral infarction (77%) and 607 as transient ischemic attack cases (12.7%); 495 patients (10.3%) corresponded to intracerebral hemorrhage. Poor functional outcome (modified Rankin scale, 3-6) was present in 1662 (34.7%) patients and 38.2% of women (P<0.001). Mortality was present in 6.8% of the registry, with 7.8% in women compared with 6.0% in men (P=0.01). Death and poor functional outcome for all-type stroke showed a higher risk in female patients (hazard ratio, 1.3, P=0.03; and hazard ratio, 1.1, P=0.001, respectively). Conclusions A worse functional outcome and higher mortality rates occurred in women compared with men in the LASE, confirming sex differences issues at short-term follow-up.

Síndrome neuroléptico maligno con mielinolisis central pontina / Neuroleptic malignant syndrome with central pontine myelinolysis

RESUMEN El síndrome neuroléptico maligno (SNM) es una complicación severa de los antipsicóticos, en especial los de primera generación como el haloperidol, que fue el primero en el que se describió esta patología, caracterizada por fiebre, rigidez, alteración del estado de conciencia y disautonomías. Por otro lado, la mielinólisis central pontina (ahora llamada síndrome de desmielinización osmótica) resulta de las alteraciones agudas séricas del sodio, como las que ocurren en las reposiciones de hiponatremia, y podría poner en riesgo la vida al igual que el SNM. La asociación de estas dos patologías es inusual y hasta el momento no se conoce con claridad su relación causal, producto de los pocos casos reportados. Aunque se conoce la mortalidad del síndrome neuroléptico maligno, la compañía de la mielinolisis central pontina podría aumentar la morbimortalidad de esta entidad, por lo cual es necesario reconocerla rápidamente para prevenir la aparición de complicaciones, ya que no cuenta con un tratamiento específico. Presentamos el caso de un paciente joven que cursó con estas dos patologías, y consideramos que la causa de la mielinolisis central pontina fue el haloperidol, así como del SNM. A pesar de ello, este medicamento continúa siendo muy seguro en la práctica clínica ya que la aparición de estas complicaciones es una reacción idiosincrática por algún tipo de susceptibilidad genética desconocida.

SUMMARY Neuroleptic malignant syndrome (NMS) is a severe complication of antipsychotics, especially those of first generation such as haloperidol, which was the first in which this pathology was described, characterized by: fever, rigidity, alteration of the state of consciousness and dysautonomies. On the other side, central pontine myelinolysis (Now Called Osmotic Demyelination Syndrome), search results of acute sodium alterations of sodium, as those occurring in hyponatremia replenings and could put life at risk just like the NMS. The association of these two pathologies is unusual and until now, their causal relationship, the result of the few cases reported, is not clearly known. Although the relationship of the neurological syndrome may be limited, the company of central myelolysis could increase the morbidity of this entity, so it is necessary to be required quickly to prevent the onset of complications, which does not have a specific treatment. We present the case of a young patient who has these pathologies and we consider that the cause of centralized myelinolysis is haloperidol as well as NMS, despite this, this medication continues to be very safe in clinical practice since the appearance of These complications is an idiosyncratic reaction due to some type of unknown genetic susceptibility.

Single-cell deep phenotyping of IgG-secreting cells for high-resolution immune monitoring.

Studies of the dynamics of the antibody-mediated immune response have been hampered by the absence of quantitative, high-throughput systems to analyze individual antibody-secreting cells. Here we describe a simple microfluidic system, DropMap, in which single cells are compartmentalized in tens of thousands of 40-pL droplets and analyzed in two-dimensional droplet arrays using a fluorescence relocation-based immunoassay. Using DropMap, we characterized antibody-secreting cells in mice immunized with tetanus toxoid (TT) over a 7-week protocol, simultaneously analyzing the secretion rate and affinity of IgG from over 0.5 million individual cells enriched from spleen and bone marrow. Immunization resulted in dramatic increases in the range of both single-cell secretion rates and affinities, which spanned at maximum 3 and 4 logs, respectively. We observed differences over time in dynamics of secretion rate and affinity within and between anatomical compartments. This system will not only enable immune monitoring and optimization of immunization and vaccination protocols but also potentiate antibody screening.

Cefalea en el adulto mayor: experiencia de una serie de 727 pacientes en el Hospital Universitario San José Infantil de Bogotá / Headache in the elderly: experience of a series of 727 patients at Hospital Universitario San José Infantil Bogotá Colombia

RESUMEN INTRODUCCIÓN: Dentro de los estudios poblacionales el grupo de adultos mayores es el de mayor crecimiento y Colombia no está ajena a dicha tendencia, por tanto el estudio de la cefalea en el adulto mayor (>65 años) es un reto diagnóstico y terapéutico en neurología. Aunque las cefaleas primarias son las más prevalentes, es importante resaltar que hay un incremento de las causas secundarias. OBJETIVO: Determinar la etiología de la cefalea primaria y secundaria en mayores de 65 años y sus características en el Hospital Universitario San José Infantil (HUSJI) de Bogotá en el periodo comprendido entre enero de 2010 y diciembre de 2015. MATERIALES Y MÉTODOS: Se realizó un estudio descriptivo retrospectivo mediante revisión de historias clínicas, en el que se determinaron las causas de cefalea primaria y secundaria según la Clasificación Internacional de Cefalea, tercera edición (IHS) y algunas de sus características. La búsqueda de estos pacientes se realizó mediante el servicio de estadística y epidemiología del hospital así como bases propias del servicio de neurología. RESULTADOS: Se incluyeron 727 pacientes que ingresaron al servicio de urgencias y hospitalización y que fueron valorados por el servicio de neurología, la edad promedio fue de 72,4 años, con una mayor prevalencia de cefalea en mujeres (70,4 %) con respecto a hombres (29,6 %). De estos 352 (48,42 %) cumplían criterios para cefalea primaria (CP) y 375 (51,58 %) para cefalea secundaria (CS). Las causas más frecuentes de cefalea secundaria fue la cefalea atribuida a desórdenes vasculares craneales o cervicales (CADV) 30 %, cefalea atribuida a desórdenes de la homeostasis (CADH) 23 %, cefalea atribuida a desórdenes del cuello (CADC) 15, 7 %. Las causas más frecuentes de cefalea primaria fueron la migraña sin aura (MSA) 34 %, migraña con aura (MCA) 26 % y cefalea tipo tensión (CTT) 21 %. CONCLUSIÓN: En el Hospital San José infantil encontramos una alta frecuencia de cefalea secundaria. Las causas secundarias en especial las vasculares y metabólicas siempre deben ser buscadas en este grupo de pacientes.

SUMMARY INTRODUCTION: Within a population studies, the older adults in one with the greatest, and Colombia is not unaware of this trend. Therefore the study of headache in the elderly (>65 years) is a diagnostic and challenge in neurology .Although the primary headaches are the most prevalent, but it should be noted there is an increase in secondary causes. OBJECTIVE: To determine the etiology of primary and secondary headache in patients over 65 years of age. Materials and methods: Descriptive and retrospective study by reviewing medical records in which the causes of primary and secondary headache were determined according to the International Classification of Headache 3rd Edition (IHS) and some of its characteristics. The search for these patients is done through the hospital statistics and epidemiology service as well as the own bases of the neurology service. RESULTS: Were incluyed 727 patients, the average age was 72.4 years, with a predominance of headache in women (70, 4%); 352 (48.42%) met criteria for primary headache (PC) and 375 (51.58%) for secondary headache (CS). The most frequent causes of CS were Headache attributed to disorders of homeostasis (CADH) 23%, headache attributed to disorders of the neck (CADC) 15, 7%, headache attributed to cranial or cervical vascular disorders (CADV). The most frequent causes of primary headache were migraine without aura (MSA) 34%, migraine with aura (MCA) 26% and headache type tension (CTT) 21%. CONCLUSION: In our group of patients, we found a higher frequency of secondary headache in patients over 65 years of age. Secondary headaches of vascular and homeostatic origin should always be sought in people over 65 years in our hospital.

Síndrome de Melas: correlación clínica con hallazgos imagenológicos en espectroscopia y tractografía, reporte de caso / Melas syndrome: clinical correlation with imaging findings in spectroscopy and tractography, case report

El síndrome de Melas es una enfermedad de herencia mitocondrial caracterizada por encefalopatía mitocondrial, acidosis láctica y eventos similares a ataque cerebrovascular, secundaria a una mutación en los genes que codifican las proteínas transportadoras de electrones, limitando la producción energética y generando disfunción multiorgánica, que afecta principalmente el sistema músculo esquelético y el sistema nervioso, lo que está en correlación con las características clínicas que presentan los pacientes. El diagnostico se basa en la sospecha clínica, los hallazgos paraclínicos e imagenológicos y la confirmación de la mutación a través del estudio genético. No existe tratamiento específico, se basa únicamente en el manejo sintomático y requiere apoyo multidisciplinario. Presentamos el caso de un paciente con antecedente de Melas, que ingresó por evento cerebrovascular isquémico bioccipital y correlación con hallazgos en neuroimágenes (espectroscopia y tractografía).

Melas syndrome is a disease characterized by mitochondrial inheritance of mitochondrial encephalopathy, lactic acidosis and events like stroke secondary to a mutation in the gene encoding the electron transport proteins limiting energy production and generating multiorgan dysfunction being affected mainly musculoskeletal system and the nervous system which correlates with the clinical characteristics presented by patients. The diagnosis is based on clinical suspicion, laboratory, and imaging findings and confirmation of the mutation through genetic study. No specific treatment is Is available, but symptomatic treatment is needed and requires multidisciplinary support. We report a patient with a history of Melas who who had bioccipital cerebral ischemic event and correlation with findings in neuroimaging (spectroscopy and tractography).

Maternal LSD1/KDM1A is an essential regulator of chromatin and transcription landscapes during zygotic genome activation.

Upon fertilization, the highly specialised sperm and oocyte genomes are remodelled to confer totipotency. The mechanisms of the dramatic reprogramming events that occur have remained unknown, and presumed roles of histone modifying enzymes are just starting to be elucidated. Here, we explore the function of the oocyte-inherited pool of a histone H3K4 and K9 demethylase, LSD1/KDM1A during early mouse development. KDM1A deficiency results in developmental arrest by the two-cell stage, accompanied by dramatic and stepwise alterations in H3K9 and H3K4 methylation patterns. At the transcriptional level, the switch of the maternal-to-zygotic transition fails to be induced properly and LINE-1 retrotransposons are not properly silenced. We propose that KDM1A plays critical roles in establishing the correct epigenetic landscape of the zygote upon fertilization, in preserving genome integrity and in initiating new patterns of genome expression that drive early mouse development.

Crystal structures of two chiral piperidine derivatives: 1-[(1R)-2-hy-droxy-1-phenyl-eth-yl]piperidin-4-one and 8-[(1S)-1-phenyl-eth-yl]-1,4-dioxa-8-aza-spiro-[4.5]decane-7-thione.

The crystal structures of the two title piperidine derivatives show different conformations for the six-membered heterocycle. The N-substituted 4-piperidinone 1-[(1R)-2-hy-droxy-1-phenyl-eth-yl]piperidin-4-one, C13H17NO2, (I), has a chair conformation, while the piperidine substituted in position 2 with a thio-carbonyl group, 8-[(1S)-1-phenyl-eth-yl]-1,4-dioxa-8-aza-spiro-[4.5]decane-7-thione, C15H19NO2S, (II), features a half-chair conformation. Comparison of the two structures, and data retrieved from the literature, suggests that the conformational flexibility is mainly related to the hybridization state of the C atom α to the piperidinic N atom: a Csp (3) atom favours the chair conformer, while a Csp (2) atom distorts the ring towards a half-chair conformer. In the crystal structure of (I), weak C-H⋯O hydrogen bonds link the mol-ecules into supra-molecular chains propagating along the b-axis direction. In the crystal of (II), the mol-ecules are linked by weak C-H⋯S contacts into supra-molecular chains propagating along the b-axis direction.

Criptococosis cerebral: descripción de una serie de casos con presentaciones típicas y atípicas en el Hospital Universitario San José Infantil de Bogotá / Cerebral cryptococcosis: description of a series of cases of atypical clinical presentation Hospital Universitario San José Infantil de Bogotá

Introducción: la criptococosis cerebral (CC) es la infección fúngica más frecuente del sistema nervioso central; se presenta especialmente en pacientes con algún tipo de inmunodeficiencia, sin embargo también puede encontrarse en inmunocompetentes, casos que son más severos y con manifestaciones neurológicas variables. Si bien las manifestaciones típicas son las más frecuentes, existen manifestaciones atípicas especialmente en pacientes inmunocompetentes que pueden llegar a presentarse en un 60% de los casos según los estudios radiológicos, por lo cual es importante reconocerlas a fin de garantizar un diagnóstico temprano y una intervención oportuna. Objetivo: describir las características clínicas de presentaciones típicas y atípicas de la criptococosis cerebral en el Hospital Universitario San José Infantil de Bogotá. Materiales y métodos: reportamos una serie de casos entre marzo de 2013 y marzo de 2014 en el Hospital Universitario San José Infantil. Se describió un total de ocho casos de criptococosis cerebral. El diagnóstico, en todos los casos, se hizo conforme a los hallazgos histopatológicos o cultivos. Resultados: de los ocho pacientes descritos, seis son hombres (75%), la mayoría menores de 60 años (=42,25 años DE 13,25); siete pacientes (87,5%) fueron inmunosuprimidos, de los cuales cinco resultaron VIH-seropositivos (62,5%). El principal motivo de consulta fue cefalea (87,5%). La clínica resultó más severa en los pacientes VIH-seronegativos. En varios pacientes se evidenciaron trastornos neuropsiquiátricos. En cinco pacientes (62,5%) se encontraron manifestaciones atípicas: criptococoma cerebral en el 25% (n = 2), ventriculitis en el 12,5% (n = 1) y trombosis séptica de senos venosos en el 25% (n = 2). Conclusión: en nuestra población con CC se evidenciaron características clínicas similares a las reportadas en otros estudios, en los que más de la mitad presentó manifestaciones atípicas, especialmente los pacientes VIH-seronegativos. Adicionalmente, se encontraron varias manifestaciones neuropsiquiátricas. Se deben tener en cuenta los cambios neuropsiquiátricos y las presentaciones atípicas sobre todo en los pacientes VIH-seronegativos con el fin de realizar un diagnóstico rápido e iniciar un tratamiento oportuno para la CC.

Introduction: Cerebral Cryptococcosis (CC) is the most common CNS fungal infection, it is especially in patients with some type of immunodeficiency, but can also be found in immunocompetent, being more severe and with variable neurological manifestations in that cases. While the typical manifestations are the most frequently seeing, atypical manifestations especially in immunocompetent patients, may present in 60% of cases as radiological studies, so it is important to recognize in order to ensure early diagnosis and timely intervention. Objective: to describe the clinical characteristics of typical and atypical presentations of cerebral cryptococcosis in Hospital Universitario San José Infantil de Bogotá. Materials and methods: we report a series of cases between March 2013 and March 2014 at the Hospital Universitario San Jose Infantil. A total of 8 cases of cerebral cryptococcosis described. The diagnosis in all cases was done according to the histopathological findings or cultures. Results: in 8 patients described 6 were men (75%), most under 60 years ( = 13.25 = 42.25 years), 7 patients (87.5%) were immunosuppressed, of which 5 HIV-seropositive patients (62.5%). The main complaint was headache (87.5%). The clinical manifestations was more severe in HIV-seronegative patients. Several patients showed neuropsychiatric disorders. In 5 patients (62.5%) atypical manifestations were found: cryptococcoma brain in 25% (n = 2), ventriculitis in 12.5% (n = 1) and septic venous sinus thrombosis in 25% (n = 2). Conclusion: in our population CC was similar to those reported in other studies, where more than half had atypical manifestations especially HIV-seronegative. Additionally several neuropsychiatric manifestations were found. Physicians should consider neuropsychiatric changes and atypical presentations essentially in HIV-seronegative patients in order to make a quick diagnosis and initiate early treatment for CC.

Proteolytic processing of the extracellular scaffolding protein LEV-9 is required for clustering acetylcholine receptors.

Correct positioning of neurotransmitter-gated receptors at postsynapses is essential for synaptic transmission. At Caenorhabditis elegans neuromuscular junctions, clustering of levamisole-sensitive acetylcholine receptors (L-AChRs) requires the muscle-secreted scaffolding protein LEV-9, a multidomain factor containing complement control protein (CCP) modules. Here we show that LEV-9 needs to be cleaved at its C terminus to exert its function. LEV-9 cleavage is not required for trafficking nor secretion but directly controls scaffolding activity. The cleavage site is evolutionarily conserved, and post-translational cleavage ensures the structural and functional decoupling between different isoforms encoded by the lev-9 gene. Data mining indicates that most human CCP-containing factors are likely cleaved C-terminally from CCP tandems, suggesting that not only domain architectures but also cleavage location can be conserved in distant architecturally related proteins.

cAMP protein kinase phosphorylates the Mos1 transposase and regulates its activity: evidences from mass spectrometry and biochemical analyses.

Genomic plasticity mediated by transposable elements can have a dramatic impact on genome integrity. To minimize its genotoxic effects, it is tightly regulated either by intrinsic mechanisms (linked to the element itself) or by host-mediated mechanisms. Using mass spectrometry, we show here for the first time that MOS1, the transposase driving the mobility of the mariner Mos1 element, is phosphorylated. We also show that the transposition activity of MOS1 is downregulated by protein kinase AMP cyclic-dependent phosphorylation at S170, which renders the transposase unable to promote Mos1 transposition. One step in the transposition cycle, the assembly of the paired-end complex, is specifically inhibited. At the cellular level, we provide evidence that phosphorylation at S170 prevents the active transport of the transposase into the nucleus. Our data suggest that protein kinase AMP cyclic-dependent phosphorylation may play a double role in the early stages of genome invasion by mariner elements.

Disparities in stroke type and vascular risk factors between 2 Hispanic populations in Miami and Mexico city.

BACKGROUND: The heterogeneous nature and determinants of stroke among different Hispanic groups was examined by comparing hospitalized Hispanic stroke patients in Miami, where the Hispanic population is largely of Caribbean origin, to a Mestizo population in Mexico City. METHODS: Consecutive Hispanic patients who were admitted with stroke or transient ischemic attack (TIA) and included in the prospective stroke registries of 2 tertiary care teaching hospitals were studied. Demographic factors, stroke subtypes, vascular risk factors, stroke severity, and outcomes were compared. Vascular risk factor definitions were standardized. RESULTS: A total of 928 patients (520 Mexicans and 408 Miami Hispanics) were analyzed. Mexicans were younger, with a greater proportion of women. More cerebral venous thromboses (CVTs) were admitted in Mexico, while TIA and stroke mimics were more commonly admitted in Miami; cardioembolic strokes were more commonly ascertained in Miami, and more cryptogenic strokes in Mexico. Stroke severity was similar for intracerebral hemorrhages, but more severe ischemic strokes and CVTs were included in the Mexican registry. Outcome at 1 and 3 months was similar in both registries after adjusting for age and baseline stroke severity. After adjusting for age and sex, hypertension, dyslipidemia, and atrial fibrillation were more frequent, and diabetes mellitus was less frequent, among Miami Hispanics compared to Mexicans. CONCLUSIONS: We found significant differences in the frequency of hypertension, diabetes, dyslipidemia, and atrial fibrillation in Miami Hispanics and Mexican stroke patients, highlighting the heterogeneity of the Hispanic ethnic group. Future studies are needed to clarify the relative contribution of genetic and environmental disparities amongst Mexican and Caribbean Hispanic stroke patients.

Positive modulation of a Cys-loop acetylcholine receptor by an auxiliary transmembrane subunit.

Auxiliary subunits regulate the trafficking, localization or gating kinetics of voltage- and ligand-gated ion channels by associating tightly and specifically with pore-forming subunits. However, no auxiliary subunits have been identified for members of the Cys-loop receptor superfamily. Here we identify MOLO-1, a positive regulator of levamisole-sensitive acetylcholine receptors (L-AChRs) at the Caenorhabditis elegans neuromuscular junction. MOLO-1 is a one-pass transmembrane protein that contains a single extracellular globular domain-the TPM domain, found in bacteria, plants and invertebrates, including nonvertebrate chordates. Loss of MOLO-1 impairs locomotion and renders worms resistant to the anthelmintic drug levamisole. In molo-1 mutants, L-AChR-dependent synaptic transmission is reduced by half, while the number and localization of receptors at synapses remain unchanged. In a heterologous expression system, MOLO-1 physically interacts with L-AChRs and directly enhances channel gating without affecting unitary conductance. The identification of MOLO-1 expands the mechanisms for generating functional and pharmacological diversity in the Cys-loop superfamily.