Intersexual Differences in the Gene Expression of Phoneutria depilata (Araneae, Ctenidae) Toxins Revealed by Venom Gland Transcriptome Analyses.

The wandering spider, Phoneutria depilata, is one of Colombia's most active nocturnal arthropod predators of vertebrates and invertebrates. Its venom has been a relevant subject of study in the last two decades. However, the scarcity of transcriptomic data for the species limits our knowledge of the distinct components present in its venom for linking the mainly neurotoxic effects of the spider venom to a particular molecular target. The transcriptome of the P. depilata venom gland was analyzed to understand the effect of different diets or sex and the impact of these variables on the composition of the venom. We sequenced venom glands obtained from ten males and ten females from three diet treatments: (i) invertebrate: Tenebrio molitor, (ii) vertebrate: Hemidactylus frenatus, and (iii) mixed (T. molitor + H. frenatus). Of 17,354 assembled transcripts from all samples, 65 transcripts relating to venom production differed between males and females. Among them, 36 were classified as neurotoxins, 14 as serine endopeptidases, 11 as other proteins related to venom production, three as metalloprotease toxins, and one as a venom potentiator. There were no differences in transcripts across the analyzed diets, but when considering the effect of diets on differences between the sexes, 59 transcripts were differentially expressed. Our findings provide essential information on toxins differentially expressed that can be related to sex and the plasticity of the diet of P. depilata and thus can be used as a reference for venomics of other wandering spider species.

Measurement of voluntary bite forces in large carnivores using a semi-automated reward-driven system.

Bite force is a key performance trait of the feeding system, but maximal in vivo bite force has been measured in few large mammals. The alternative, modelling of bite force from anatomy, cannot be validated without in vivo measurements. To overcome existing limitations of ethics, safety and animal well-being, we propose a semi-automated method to obtain voluntary maximum bite forces from large mammals using bite plates that automatically dispense a food reward if an incrementally increasing threshold force value is reached. We validated our method using two Malayan sun bears, two Andean spectacled bears and a lioness. We show that voluntary bite force measurement using positive reinforcement is a non-invasive and reliable method to record maximum voluntary bite force performance in large mammals. Our results further show that in vivo data are critical as modeling efforts from osteology have greatly underestimated bite forces in Andean spectacled bears.

Bi-nasal sectors of ganglion cells complex and visual evoked potential amplitudes as biomarkers in pituitary macroadenoma management.

The study aimed to evaluate the retinal ganglion cell structure using optical coherence tomography and the visual pathway function employing visual evoked potentials in the diagnosis and monitoring of patients with pituitary macroadenoma. A descriptive, cross-sectional, and longitudinal study (3 and 12 months follow-up) was conducted on forty-two patients. Thirty-five age-matched healthy controls were used in the cross-sectional one. Full neuro-ophthalmological evaluation (structural and functional) was carried out including global and segmented retinal nerve fiber layer/ganglion cell complex analysis and amplitude and latency of P100 component in the electrophysiology. Statistical data analysis was conducted with R version 3.6.3 and Python version 3.8. Associations were evaluated using Spearman's correlations. Amplitude sensitivities were 0.999, and bi-nasal sectors of ganglion cell complex thickness specificities were 0.999. This structural parameter had the highest diagnostic value (area under curve = 0.923). Significant associations were found between bi-nasal sectors with amplitude at 12' (rho > 0.7, p < 0.01) and median deviation of the visual field (rho > 0.5, p < 0.01) at 3 months. Pre-surgical values of bi-nasal sectors and amplitude can predict post-surgically median deviation and amplitude (Oz, 12') at 3 months with r 2 > 0.5. Bi-nasal sectors of ganglion cell complex and visual evoked potentials P100 amplitude are efficient biomarkers of visual pathway damage for pituitary macroadenoma patients' management. Pre-surgical values of the bi-nasal sector and visual evoked potentials' amplitude could help to predict the restoration of parvocellular pathway traffic after decompression.

Caracterización de las lesiones compresivas de la vía visualanterior / Characterization of Compressive Lesions of the Anterior VisualPathway

Objetivo: Determinar las características clínico-epidemiológicas de los pacientes diagnosticados con lesiones compresivas de la vía visual anterior. Métodos: Se realizó un estudio descriptivo transversal durante el período comprendido entre mayo de 2018 y marzo de 2020 con 41 pacientes con diagnóstico de síndrome compresivo de la vía visual anterior atendidos en el Servicio de Neuroftalmología del Instituto Cubano de Oftalmología "Ramón Pando Ferrer". Resultados: La mayor frecuencia en cuanto a síntomas fue la disminución progresiva de la visión central. Se encontraron lesiones de tipo tumoral en 39 pacientes para el 95,1 por ciento. Los defectos hemianópticos se detectaron en el campo visual del 45 por ciento de la muestra y el 33 por ciento presentó disminución difusa de la sensibilidad retiniana. Conclusiones: La mayoría de los pacientes fueron del sexo femenino en edades medias de la vida. Predominaron las lesiones tumorales sobre las vasculares. Los macroadenomas de hipófisis y los meningiomas fueron las etiologías más frecuentes y el sitio de compresión más encontrado fue el quiasma óptico. Se detectó disminución del grosor del complejo de células ganglionares maculares en la tomografía de coherencia óptica de la mayoría de los enfermos(AU)

Objective: To determine the clinical-epidemiological characteristics of patients diagnosed with compressive lesions of the anterior visual pathway. Methods: A cross-sectional descriptive study was conducted during the period from May 2018 to March 2020 with 41 patients diagnosed with compressive syndrome of the anterior visual pathway attended at the Neurophthalmology Service of the Cuban Institute of Ophthalmology "Ramón Pando Ferrer". Results: The most frequent symptom was the progressive decrease of central vision. Tumor type lesions were found in 39 patients for 95.1 percent. Hemianoptic defects were detected in the visual field of 45 percent of the sample and 33 percent presented diffuse decrease of retinal sensitivity. Conclusions: The majority of patients were female at middle ages of life. Tumor lesions predominated over vascular lesions. Pituitary macroadenomas and meningiomas were the most frequent etiologies and the most frequent site of compression was the optic chiasm. Decreased thickness of the macular ganglion cell complex was detected in the optical coherence tomography of most of the patients(AU)

Chagas disease reactivation after autologous stem cell transplant. Case report and literature review / Reactivación de la enfermedad de Chagas después de trasplante autólogo de progenitores hematopoyéticos. Reporte de caso y revisión de la literatura

Introduction: Chagas disease is an endemic parasitic infection in Latin America transmitted by triatomines. It is associated with risk factors such as poverty and rurality. After acute infection, a third of patients will present target organ involvement (heart, digestive tract, central nervous system). The remaining two thirds remain asymptomatic throughout their life. Pharmacological immunosuppression breaks the balance between the immune system and the parasite, favoring its reactivation. Clinical case: We present the case of a 58-year-old man from a Colombian rural area with a diagnosis of multiple myeloma refractory to the first line of treatment who required a new chemotherapy scheme and consolidation with autologous stem cell transplant. During the post-transplant period, he suffered from febrile neutropenia. Initial microbiological studies were negative but the peripheral blood smear evidenced trypomastigotes in blood. With a diagnosis of acute Chagas disease in a post-transplant patient, benznidazole was started. The evolution of the patient was satisfactory. Conclusions: Positive serology prior to transplantation makes it necessary to rule out reactivation of the pathology in the setting of febrile neutropenia. More studies are required to determine tools for estimating the probability of reactivation of the disease and defining the best cost-risk-benefit relation for the prophylactic therapy.

Introducción. La enfermedad de Chagas es una parasitosis endémica en Latinoamérica transmitida por triatominos. Está asociada a factores de riesgo como la pobreza y la ruralidad. Después de la infección aguda, un tercio de los pacientes presenta compromiso del corazón, el aparato digestivo o el sistema nervioso central, en tanto que los dos tercios restantes no presentan este tipo de compromiso secundario. La inmunosupresión farmacológica rompe el equilibrio entre el sistema inmunitario y el parásito, lo cual favorece su reactivación. Caso clínico. Se presenta el caso de un hombre de 58 años procedente de un área rural colombiana, con diagnóstico de mieloma múltiple resistente a los fármacos de primera línea de tratamiento, que requirió un nuevo esquema de quimioterapia y consolidación con trasplante autólogo de células madre. Después del trasplante, presentó neutropenia febril. Los estudios microbiológicos iniciales fueron negativos. En el frotis de sangre periférica, se demostraron tripomastigotes y se diagnosticó enfermedad de Chagas aguda posterior al trasplante. Se inició el tratamiento con benznidazol. La evolución del paciente fue satisfactoria. Conclusiones. La serología positiva para Chagas previa a un trasplante obliga a descartar la reactivación de la enfermedad en caso de neutropenia febril. Se requieren más estudios para determinar las herramientas que permitan estimar la probabilidad de reactivación de la enfermedad y decidir sobre la mejor opción de relación entre costo, riesgo y beneficio de la terapia profiláctica.

Pinching or stinging? Comparing prey capture among scorpions with contrasting morphologies.

Background: Scorpions can use their pincers and/or stingers to subdue and immobilize their prey. A scorpion can thus choose between strategies involving force or venom, or both, depending on what is required to subdue its prey. Scorpions vary greatly in the size and strength of their pincers, and in the efficacy of their venom. Whether this variability is driven by their defensive or prey incapacitation functionis unknown. In this study, we test if scorpion species with different pincer morphologies and venom efficacies use these weapons differently during prey subjugation. To that end, we observed Opisthacanthus elatus and Chactas sp. with large pincers and Centruroides edwardsii and Tityus sp. with slender pincers. Methods: The scorpion pinch force was measured, and behavioral experiments were performed with hard and soft prey (Blaptica dubia and Acheta domesticus). Stinger use, sting frequency and immobilization time were measured. Results: We found that scorpions with large pincers such as O. elatus produce more force and use the stinger less, mostly subjugating prey by crushing them with the pincers. In C. edwardsii and Tityus sp. we found they use their slender and relatively weak pincers for holding the prey, but seem to predominantly use the stinger to subjugate them. On the other hand, Chactas sp. uses both strategies although it has a high pinch force. Conclusions: Our results show that scorpionspecies with massive pincers and high pinch force as O. elatus use the stinger less for prey subjugation than scorpionspecies with slenderpincers.

Comparison of biological activities of Tityus pachyurus venom from two Colombian regions.

BACKGROUND: In the present study, we have tested whether specimens of the medically relevant scorpion Tityus pachyurus, collected from two climatically and ecologically different regions, differ in the biological activities of the venom. METHODS: Scorpions were collected in Tolima and Huila, Colombia. Chemical profiles of the crude venom were obtained from 80 scorpions for each region, using SDS-PAGE and RP-HPLC. Assays for phospholipase A2, direct and indirect hemolytic, proteolytic, neuromuscular, antibacterial, and insecticidal activities were carried out. RESULTS: The electrophoretic profiles of venom from the two regions showed similar bands of 6-14 kDa, 36-45 kDa, 65 kDa and 97 kDa. However, bands between 36 kDa and 65 kDa were observed with more intensity in venoms from Tolima, and a 95 kDa band occurred only in venoms from Huila. The chromatographic profile of the venoms showed differences in the intensity of some peaks, which could be associated with changes in the abundance of some components between both populations. Phospholipase A2 and hemolytic activities were not observable, whereas both venoms showed proteolytic activity towards casein. Insecticidal activity of the venoms from both regions showed significant variation in potency, the bactericidal activity was variable and low for both venoms. Moreover, no differences were observed in the neuromuscular activity assay. CONCLUSION: Our results reveal some variation in the activity of the venom between both populations, which could be explained by the ecological adaptations like differences in feeding, altitude and/or diverse predator exposure. However more in-depth studies are necessary to determine the drivers behind the differences in venom composition and activities.

Risk Prediction of Death in Inpatient Adults With COVID-19 from Mexico.

Background: There is substantial variation in COVID-19 lethality across countries. In addition, in countries with populations with extreme economic inequalities, such as Mexico, there are regional and local differences in risk factors for COVID-19 death. The goal of this study was to test the hypothesis that the risk of death in Mexican COVID-19 patients was associated with the time between symptom onset and hospitalization and/or with the healthcare site. Also, death prognostic models were developed. Methods: The study included two COVID-19 inpatient cohorts, one prospective and one retrospective from Chiapas, Mexico. Demographic, clinical and laboratory variables were collected, and the diagnosis of SARS-CoV-2 infection was performed using RT-qPCR in samples collected seven days since symptom onset. The 30-day mortality, since symptom onset, was the outcome, and clinical variables at the first 48 hours of hospitalization were independent factors. Multivariate logistic regression analyses were conducted. Results: Of the 392 patients included, 233 died (59.4%). The time between symptom onset and hospitalization, the healthcare site and sex were not related to the 30-day mortality. Three death prognostic models were developed (AUC between 0.726 and 0.807). Age, LDH, AST, and lymphocyte count were included in all models, OSI-WHO Classification (Non-invasive ventilation or high-flow oxygen, and mechanical ventilation with or without organ support/ECMO) and leukocyte count in two models, and diabetes and diarrhea in one model. Conclusion: The population evaluated had underlying deteriorated health before COVID-19 compared with regional and country population. The factors that determine the COVID-19 mortality risk in a relatively healthy population are sex, age and comorbidities. However, as this study shows, when populations have underlying poor health, some of these factors lose their associations with mortality risk, and others become more important.

Multidrug-resistant Raoultella ornithinolytica misidentified as Klebsiella oxytoca carrying blaOXA ß-lactamases: antimicrobial profile and genomic characterization.

Class D ß-lactamases OXA-232 and OXA-48 hydrolyze penicillin, cephalosporins and carbapenems, limiting the pharmacological therapeutics in bacteraemia. OXA producer microorganisms are considered a great emergent threat, especially in nosocomial environments. To determine the resistance profile and genomic characterization of two isolates initially identified as potential carbapenemase-producer Klebsiella oxytoca in a third level hospital. Automated platform BD Phoenix-100 System was used to identify and to biochemically characterize both isolates. Furthermore, the resistance profile was determined through CLSI methods and the whole genome sequences were obtained using Next-Generation Sequencing. Resistance genes were analyzed, and the virtual fingerprinting was determined to corroborate the similarity with related bacteria. Both strains correspond to Raoultella ornithinolytica carrying OXA 232 and OXA-48 genes, confirming the class D ß-lactamases assay results. Here, we present the genetic and phenotypic analysis of multidrug resistance R. ornithinolytica, representing the first report in Mexico.

Deciphering the diet of a wandering spider (Phoneutria boliviensis; Araneae: Ctenidae) by DNA metabarcoding of gut contents.

Arachnids are the most abundant land predators. Despite the importance of their functional roles as predators and the necessity to understand their diet for conservation, the trophic ecology of many arachnid species has not been sufficiently studied. In the case of the wandering spider, Phoneutria boliviensis F. O. Pickard-Cambridge, 1897, only field and laboratory observational studies on their diet exist. By using a DNA metabarcoding approach, we compared the prey found in the gut content of males and females from three distant Colombian populations of P. boliviensis. By DNA metabarcoding of the cytochrome c oxidase subunit I (COI), we detected and identified 234 prey items (individual captured by the spider) belonging to 96 operational taxonomic units (OTUs), as prey for this wandering predator. Our results broaden the known diet of P. boliviensis with at least 75 prey taxa not previously registered in fieldwork or laboratory experimental trials. These results suggest that P. boliviensis feeds predominantly on invertebrates (Diptera, Lepidoptera, Coleoptera, and Orthoptera) and opportunistically on small squamates. Intersex and interpopulation differences were also observed. Assuming that prey preference does not vary between populations, these differences are likely associated with a higher local prey availability. Finally, we suggest that DNA metabarcoding can be used for evaluating subtle differences in the diet of distinct populations of P. boliviensis, particularly when predation records in the field cannot be established or quantified using direct observation.

Klebsiella pneumoniae blaNDM-1 carrying a class 1 integron causing a hospital outbreak in a Mexican attention center.

INTRODUCTION: Infections acquired in hospitals are the cause of high morbidity and mortality and with the emergence of resistant bacteria, the problem is greater. The aim of this work was to determine the genetic characteristics and timeline of Klebsiella pneumoniae blaNDM-1 carrying a class 1 integron involved in an intrahospital outbreak. METHODOLOGY: Investigation was made from the first detection of K. pneumoniae blaNDM-1, strain "466", and the last clone "423". 16S rRNA gene analysis showed that 466 strain and clones were related to K. pneumoniae. Extended-spectrum ß-lactamases (ESBL) was detected according to the Clinical and Laboratory Standards Institute (CLSI) and real time-PCR. Typing of K. pneumoniae blaNDM-1 strains was carried by ERIC-PCR and sequencing the variable region of the integrons were performed. RESULTS: A cluster of six resistant isolates of K. pneumoniae blaNDM-1 was detected in intensive care unit (ICU), internal medicine (IM) and orthopedics (OT). Timeline revealed that the first bacterial identification was in ICU and the last clone in OT service. The array genetic of variable region was "IntI/aadA5-drfA17/qacEΔ1-Sul1". CONCLUSIONS: The evidences highlight the importance of the epidemiological surveillance of Extended-spectrum ß-lactamases (ESBL) strains, as well as the need for molecular epidemiological studies to identify the routes of transmission and the contamination sources within health personnel.

Aneurisma de la arteria carótida interna como lesión compresiva de la vía visual / Internal carotid artery aneurysm as a compressive lesion of the visual pathway

El diagnóstico temprano de las lesiones compresivas del nervio óptico adquiere cada vez mayor importancia. La descompresión precoz de este o del quiasma puede resultar una mejora significativa de la función visual, mientras que el diagnóstico erróneo puede ocasionar pérdida visual irreversible, disfunción neurológica o la muerte. Las causas de la compresión de la vía visual anterior son increíblemente variadas. Los meningiomas, los tumores hipofisarios y los aneurismas son las lesiones comúnmente más identificadas como causa de neuropatía óptica compresiva sin edema del disco. Presentamos una paciente femenina de 50 años de edad, quien se sometió a la cirugía de catarata congénita del ojo izquierdo, sin mejoría de la función visual, a lo que se sumó el empeoramiento inespecífico de la calidad visual. La psicofísica visual, la campimetría automatizada y la tomografía de coherencia óptica aportaron hallazgos sugestivos de compresión de la vía visual intracraneal. Se indicó imagen por resonancia magnética de cráneo y órbitas para confirmar la sospecha diagnóstica. La angiografía cerebral demostró la presencia de un aneurisma de la arteria carótida interna, que se trató por vía endovascular con resultados satisfactorios(AU)

The importance of early diagnosis of compressive lesions of the optic nerve is on the increase. Timely decompression of the optic nerve or the optic chiasm may bring about significant visual function improvement, whereas erroneous diagnosis may result in irreversible visual loss, neurological dysfunction or death. The causes of compression of the anterior visual pathway are incredibly varied. Meningiomas, pituitary tumors and aneurysms are the lesions most commonly identified as causes of compressive optic neuropathy without disc edema. A case is presented of a female 50-year-old patient undergoing congenital cataract surgery of her left eye without visual function improvement, alongside unspecific visual quality worsening. Visual psychophysical testing, automated campimetry and optical coherence tomography contributed findings suggestive of intracranial visual pathway compression. Magnetic resonance imaging of the brain and orbits was indicated to confirm the diagnostic suspicion. Cerebral angiography revealed the presence of an internal carotid artery aneurysm which was treated by endovascular procedure with satisfactory results(AU)

Comparison of biological activities of Tityus pachyurus venom from two Colombian regions

Background: In the present study, we have tested whether specimens of the medically relevant scorpion Tityus pachyurus, collected from two climatically and ecologically different regions, differ in the biological activities of the venom. Methods: Scorpions were collected in Tolima and Huila, Colombia. Chemical profiles of the crude venom were obtained from 80 scorpions for each region, using SDS-PAGE and RP-HPLC. Assays for phospholipase A2, direct and indirect hemolytic, proteolytic, neuromuscular, antibacterial, and insecticidal activities were carried out. Results: The electrophoretic profiles of venom from the two regions showed similar bands of 6-14 kDa, 36-45 kDa, 65 kDa and 97 kDa. However, bands between 36 kDa and 65 kDa were observed with more intensity in venoms from Tolima, and a 95 kDa band occurred only in venoms from Huila. The chromatographic profile of the venoms showed differences in the intensity of some peaks, which could be associated with changes in the abundance of some components between both populations. Phospholipase A2 and hemolytic activities were not observable, whereas both venoms showed proteolytic activity towards casein. Insecticidal activity of the venoms from both regions showed significant variation in potency, the bactericidal activity was variable and low for both venoms. Moreover, no differences were observed in the neuromuscular activity assay. Conclusion: Our results reveal some variation in the activity of the venom between both populations, which could be explained by the ecological adaptations like differences in feeding, altitude and/or diverse predator exposure. However more in-depth studies are necessary to determine the drivers behind the differences in venom composition and activities.(AU)

Comparison of biological activities of Tityus pachyurus venom from two Colombian regions

Abstract Background: In the present study, we have tested whether specimens of the medically relevant scorpion Tityus pachyurus, collected from two climatically and ecologically different regions, differ in the biological activities of the venom. Methods: Scorpions were collected in Tolima and Huila, Colombia. Chemical profiles of the crude venom were obtained from 80 scorpions for each region, using SDS-PAGE and RP-HPLC. Assays for phospholipase A2, direct and indirect hemolytic, proteolytic, neuromuscular, antibacterial, and insecticidal activities were carried out. Results: The electrophoretic profiles of venom from the two regions showed similar bands of 6-14 kDa, 36-45 kDa, 65 kDa and 97 kDa. However, bands between 36 kDa and 65 kDa were observed with more intensity in venoms from Tolima, and a 95 kDa band occurred only in venoms from Huila. The chromatographic profile of the venoms showed differences in the intensity of some peaks, which could be associated with changes in the abundance of some components between both populations. Phospholipase A2 and hemolytic activities were not observable, whereas both venoms showed proteolytic activity towards casein. Insecticidal activity of the venoms from both regions showed significant variation in potency, the bactericidal activity was variable and low for both venoms. Moreover, no differences were observed in the neuromuscular activity assay. Conclusion: Our results reveal some variation in the activity of the venom between both populations, which could be explained by the ecological adaptations like differences in feeding, altitude and/or diverse predator exposure. However more in-depth studies are necessary to determine the drivers behind the differences in venom composition and activities.

Hemorragia peripapilar subretinal profunda como complicación asociada a drusen de nervio óptico / Deep subretinal peripapillary bleeding as a complication associated to optic nerve drusen

RESUMEN Los drusen de nervio óptico fueron descritos por primera vez por Liebreich en el año 1868. Otros términos para designar esta entidad incluyen cuerpos hialinos y cuerpos coloides del disco óptico. Tienen una prevalencia de 1 por 500 y el 60 por ciento de los casos se encuentran profundos en la cabeza del nervio óptico. La patogenia primaria de los drusen puede ser una displasia hereditaria del canal óptico del disco óptico y su vasculatura, lo que predispone a la formación de estos. La evolución natural de los drusen es un proceso dinámico que transcurre durante toda la vida. Entre las complicaciones asociadas se presentan defectos de campo visual, pérdida de visión central (rara pero bien documentada), neuropatía óptica isquémica, oclusiones vasculares retinales, pérdidas transitorias de la visión, neovascularización subretinal peripapilar, corioretinopatia serosa central peripapilar y hemorragias pre y peripapilares. Se presenta una paciente de 64 años de edad con antecedente de haber sido operada de desprendimiento de retina del ojo izquierdo, y en el ojo derecho presentaba una hemorragia peripapilar subretinal profunda asociada a drusen(AU)

ABSTRACT Optic nerve drusens were first described by Liebreich in the year 1868. Other terms to designate this condition are optic disc hyaline bodies and colloid bodies. They have a prevalence of 1 per 500 and 60 percent of the cases occur deep in the optic nerve head. The primary pathogenesis of drusens may be an inherited dysplasia of the optic canal of the disc and its vasculature, which leads to their formation. The natural evolution of drusens is a lifelong dynamic process. Associated complications include visual field defects, central vision loss (rare but well documented), ischemic optic neuropathy, retinal vascular occlusion, transient sight loss, peripapillary subretinal neovascularization, central serous peripapillary chorioretinopathy, and pre- and peripapillary bleeding. A case is reported of a 64-year-old female patient with a history of surgery for retinal detachment of the left eye. In the right eye the patient presented deep peripapillary subretinal bleeding associated to drusen(AU)