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1.
Emerg Infect Dis ; 30(1): 180-182, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38063085

ABSTRACT

We estimated the incubation period for mpox during an outbreak in Pereira, Colombia, using data from 11 confirmed cases. Mean incubation period was 7.1 (95% CI 4.9-9.9) days, consistent with previous outbreaks. Accurately estimating the incubation period provides insights into transmission dynamics, informing public health interventions and surveillance strategies.


Subject(s)
Mpox (monkeypox) , Male , Humans , Colombia/epidemiology , Infectious Disease Incubation Period , Disease Outbreaks , Public Health , Homosexuality, Male
2.
J Cell Biol ; 222(11)2023 11 06.
Article in English | MEDLINE | ID: mdl-37707499

ABSTRACT

Astrocytes control the formation of specific synaptic circuits via cell adhesion and secreted molecules. Astrocyte synaptogenic functions are dependent on the establishment of their complex morphology. However, it is unknown if distinct neuronal cues differentially regulate astrocyte morphogenesis. δ-Catenin was previously thought to be a neuron-specific protein that regulates dendrite morphology. We found δ-catenin is also highly expressed by astrocytes and required both in astrocytes and neurons for astrocyte morphogenesis. δ-Catenin is hypothesized to mediate transcellular interactions through the cadherin family of cell adhesion proteins. We used structural modeling and biochemical analyses to reveal that δ-catenin interacts with the N-cadherin juxtamembrane domain to promote N-cadherin surface expression. An autism-linked δ-catenin point mutation impaired N-cadherin cell surface expression and reduced astrocyte complexity. In the developing mouse cortex, only lower-layer cortical neurons express N-cadherin. Remarkably, when we silenced astrocytic N-cadherin throughout the cortex, only lower-layer astrocyte morphology was disrupted. These findings show that δ-catenin controls astrocyte-neuron cadherin interactions that regulate layer-specific astrocyte morphogenesis.


Subject(s)
Astrocytes , Cadherins , Delta Catenin , Morphogenesis , Animals , Mice , Cadherins/genetics , Delta Catenin/genetics , Neurons
3.
J Anim Ecol ; 92(2): 324-337, 2023 02.
Article in English | MEDLINE | ID: mdl-36059124

ABSTRACT

Studying species interactions in nature often requires elaborated logistics and intense fieldwork. The difficulties in such task might hinder our ability to answer questions on how biotic interactions change with the environment. Fortunately, a workaround to this problem lies within scientific collections. For some animals, the inspection of preserved specimens can reveal the scars of past antagonistic encounters, such as predation attempts. A common defensive behaviour that leaves scars on animals is autotomy, the loss of a body appendage to escape predation. By knowing the collection site of preserved specimens, it is possible to assess the influence of organismal biology and the surrounding environment in the occurrence of autotomy. We gathered data on tail loss for 8189 preserved specimens of 33 snake and 11 amphisbaenian species to investigate biological and environmental correlates of autotomy in reptiles. We applied generalized linear mixed effect models to evaluate whether body size, sex, life-stage, habitat use, activity pattern, biome, tropicality, temperature and precipitation affect the probability of tail loss in limbless reptiles. We observed autotomy in 23.6% of examined specimens, with 18.7% of amphisbaenian and 33.4% of snake specimens showing tail loss. The probability of tail loss did not differ between snakes and amphisbaenians, but it was higher among large-sized specimens, particularly in adults and females. Chance of tail loss was higher for diurnal and arboreal species, and among specimens collected in warmer regions, but it was unaffected by biome, precipitation, and tropicality. Autotomy in limbless reptiles was affected by size-dependent factors that interplay with ontogeny and sexual dimorphism, although size-independent effects of life-stage and sex also shaped behavioural responses to predators. The increase in probability of tail loss with verticality and diurnality suggests a risk-balance mechanism between species habitat use and activity pattern. Although autotomy is more likely in warmer regions, it seems unrelated to seasonal differences in snakes and amphisbaenians activity. Our findings reveal several processes related to predator-prey interactions involving limbless reptiles, demonstrating the importance of scientific collections to unveil ecological mechanisms at different spatio-temporal scales.


Subject(s)
Lizards , Female , Animals , Lizards/physiology , Tail/physiology , Predatory Behavior , Cicatrix , Ecosystem
4.
JCI Insight ; 7(23)2022 12 08.
Article in English | MEDLINE | ID: mdl-36256481

ABSTRACT

High endothelial venule protein/SPARC-like 1 (hevin/Sparcl1) is an astrocyte-secreted protein that regulates synapse formation in the brain. Here we show that astrocytic hevin signaling plays a critical role in maintaining chronic pain. Compared with WT mice, hevin-null mice exhibited normal mechanical and heat sensitivity but reduced inflammatory pain. Interestingly, hevin-null mice have faster recovery than WT mice from neuropathic pain after nerve injury. Intrathecal injection of WT hevin was sufficient to induce persistent mechanical allodynia in naive mice. In hevin-null mice with nerve injury, adeno-associated-virus-mediated (AAV-mediated) re-expression of hevin in glial fibrillary acidic protein-expressing (GFAP-expressing) spinal cord astrocytes could reinstate neuropathic pain. Mechanistically, hevin is crucial for spinal cord NMDA receptor (NMDAR) signaling. Hevin-potentiated N-Methyl-D-aspartic acid (NMDA) currents are mediated by GluN2B-containing NMDARs. Furthermore, intrathecal injection of a neutralizing Ab against hevin alleviated acute and persistent inflammatory pain, postoperative pain, and neuropathic pain. Secreted hevin that was detected in mouse cerebrospinal fluid (CSF) and nerve injury significantly increased CSF hevin abundance. Finally, neurosurgery caused rapid and substantial increases in SPARCL1/HEVIN levels in human CSF. Collectively, our findings support a critical role of hevin and astrocytes in the maintenance of chronic pain. Neutralizing of secreted hevin with monoclonal Ab may provide a new therapeutic strategy for treating acute and chronic pain and NMDAR-medicated neurodegeneration.


Subject(s)
Chronic Pain , Neuralgia , Humans , Mice , Animals , Receptors, N-Methyl-D-Aspartate , Spinal Cord , Calcium-Binding Proteins , Extracellular Matrix Proteins
5.
Med. UIS ; 35(1): 71-79, ene,-abr. 2022. tab
Article in Spanish | LILACS | ID: biblio-1394434

ABSTRACT

Resumen Introducción: la hipovitaminosis D es un problema prevalente en la población general y muy frecuente en niños; relacionado a diferentes patologías o factores como el uso de medicamento antiepilépticos (MAEs), principalmente aquellos inductores enzimáticos del citocromo P450, ampliamente relacionados con la salud ósea. Razón por la que este estudio busca determinar la distribución de insuficiencia de Vitamina D en niños tratados farmacológicamente para la epilepsia, así como establecer factores asociados basándose en características sociodemográficas, clínicas y terapéuticas. Metodología: estudio descriptivo, transversal, retrospectivo con 103 pacientes con epilepsia en manejo con MAEs, asistentes a la consulta de neuropediatría en un hospital de tercer nivel, se tomó información de las historias clínicas de niños entre 0 y 18 años durante enero del 2016 y junio del 2019. Se construyó un modelo multivariado en relación a la presencia de insuficiencia de vitamina D y valores normales de esta. Resultados: el 44,7% presentaron insuficiencia de vitamina D, mientras 6,8% de pacientes presentó deficiencia, de los cuales 4 tenían historia de fracturas. Se encontró asociación estadísticamente significativa con la insuficiencia en pacientes que residen en área rural (ORa=4,2 (IC95=1,3-13,4) p=0,013), pertenecen a nivel socio económico bajo (Ora=2,9 (IC95%=1,1-77) p=0,030) y padecen epilepsia refractaria (Ora=3,1 (IC95%=1-8,7) p=0,033). Conclusiones: la hipovitaminosis D es frecuente en paciente con epilepsia en manejo farmacológico con MAE. La insuficiencia se asoció con epilepsia refractaria, nivel socioeconómico bajo y provenir de área rural, por lo que se recomienda vigilancia rutinaria de los niveles de vitamina D y suplementación en aquellos pacientes con déficit. MÉD.UIS.2022;35(1): 71-9


Abstract Hypovitaminosis D is a prevalent problem in the general population and very common in children; related to different pathologies or factors such as the use of antiepileptic drugs (MAEs), mainly those enzymatic inducers of cytochrome P450, broadly related with bone health. Reason why this study seeks to determine the distribution of vitamin D insufficiency in children with epilepsy in pharmacological treatment and to establish associated factors based on sociodemographic, clinical, and therapeutic characteristics. Methodology: descriptive, cross- sectional, retrospective study with 103 patients with epilepsy in management with MAEs, attending the neuropaediatric consultation in a third-level hospital, information was taken from the medical records of children between 0 and 18 years of age during January 2016 and June 2019. A multivariate model was built in relation to the presence of vitamin D insufficiency and its normal values. Results: 44.7% of patients had vitamin D insufficiency, while 6.8% had deficiency, of which 4 had a history of fractures. A statistically significant association with insufficiency was found in patients residing in rural areas (ORa=4.2 (IC95=1.3-13.4) p=0.013), they belong to a low socio-economic level (Ora=2.9 (95% CI=1.1-77) p=0.030) and suffering from refractory epilepsy (Ora=3.1 (95% CI=1-8.7) p=0.033). Conclusions: hypovitaminosis D is frequent in a patient with epilepsy under pharmacological management with MAE. Insufficiency was associated with refractory epilepsy, low socioeconomic status and coming from rural areas, so routine monitoring of vitamin D levels is recommended in those patients with deficits. MÉD.UIS.2022;35(1): 71-9


Subject(s)
Humans , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Vitamin D Deficiency , Epilepsy , Fractures, Bone , Anticonvulsants
6.
Structure ; 29(7): 635-637, 2021 07 01.
Article in English | MEDLINE | ID: mdl-34214438

ABSTRACT

Astrocyte-secreted Hevin induces synapse formation by bridging the trans-synaptic organizers, neuroligins and neurexins. In this issue of Structure, Fan et al. (2021) elucidate the structural basis of Hevin's interaction with these molecules and reveal the competitive interplay between Hevin, SPARC, and MDGAs.


Subject(s)
Cell Adhesion Molecules, Neuronal , Synapses , Cell Adhesion Molecules, Neuronal/genetics
7.
PeerJ ; 8: e9901, 2020.
Article in English | MEDLINE | ID: mdl-33024630

ABSTRACT

BACKGROUND: Pandi's mushroom-tongue salamander (Bolitoglossa pandi) is one of the threatened amphibians in South America, as well as a flagship species for the Colombian conservation agenda. This species is endemic to the Andean cloud forests of the western slope of the Cordillera Oriental of Colombia, occurring only in the department of Cundinamarca within a narrow elevational range. At night, B. pandi can be seen perching on the upper side of leaves at heights ranging from ground level to 2.5 m. During the day, it can be found under leaf litter or cover objects. Few studies have provided relevant information that can help the Colombian government to formulate lines of action for the conservation of this species; consequently, its threat assessments so far have been based on very limited information. METHODS: We conducted surveys for salamanders in four municipalities of Cundinamarca, Colombia, using two approaches: visual encounter surveys (Guaduas and Villeta) and the basic sampling protocol for single-species occupancy modeling (Supatá and Venecia). Multivariate analyses were employed to explore the correlation between habitat structure and natural history traits, abundance, and detection/non-detection of B. pandi. We evaluated the B. pandi activity pattern through kernel density curves for each sampling occasion and explored the variability of salamander abundance during their activity period by performing a nested ANOVA. RESULTS: We report the discovery of two new populations of B. pandi, which represent the most northwestern records known. A significant correlation between body length, body mass, and habitat structure was observed. Multivariate analyses indicated that leaf litter depth, mean temperature, percent vegetation cover, and altitude were the habitat variables that together explained 60.3% of the B. pandi abundance variability, as well as the main determinants of its optimal habitat. Bolitoglossa pandi exhibits an activity pattern characterized by two main activity peaks, in which niche time-partitioning was observed. Across the surveyed area, we found a healthy, stable, highly dense population of B. pandi (>1,300 individuals), with seasonal variability between development stages. DISCUSSION: Given the high habitat specificity of B. pandi, the species is highly vulnerable to local changes. Thus, we recommend that B. pandi be retained as Endangered (EN) on the IUCN Red List, based on the IUCN Criterion B, given its restricted extent of occurrence (ca. 2,500 km2) and the ongoing threats from agriculture, cattle ranching, logging, and urban development, which continue to reduce its suitable habitat.

8.
Gac Med Mex ; 156(2): 132-137, 2020.
Article in English | MEDLINE | ID: mdl-32285862

ABSTRACT

On December 31, 2019, the Chinese health authorities informed the international community, through the mechanisms established by the World Health Organization (WHO), of a pneumonia epidemic of unknown etiology in Wuhan, Hubei Province. The first cases were reported early in that month and were linked to a history of having visited a market where food and live animals are sold. On January 7, 2020, isolation and identification of the culprit pathogen was achieved using next-generation sequencing, while the number of affected subjects continued to rise. The publication of full-genomes of the newly identified coronavirus (initially called 2019-nCoV, now called SARS-CoV2) in public and private databases, of standardized diagnostic protocols and of the clinical-epidemiological information generated will allow addressing the Public Health Emergency of International Concern (PHEIC), declared on January 30 by the WHO. With this document, we intend to contribute to the characterization of the pneumonia epidemic, now designated coronavirus disease (Covid-19) review the strengths Mexico has in the global health concert and invite health professionals to join the preparedness and response activities in the face of this emergency.


El 31 de diciembre de 2019, las autoridades chinas de salud informaron a la comunidad internacional, a través de los mecanismos establecidos por la Organización Mundial de la Salud (OMS), de una epidemia de neumonía con etiología desconocida en Wuhan, provincia de Hubei. Los primeros casos se notificaron a inicios de ese mes y se vincularon al antecedente de visitar un mercado de comida y animales vivos. El 7 de enero de 2020 se logró el aislamiento y reconocimiento del patógeno responsable mediante secuenciación de siguiente generación, mientras el número de afectados continuaba en ascenso. La publicación de genomas completos del nuevo coronavirus identificado (inicialmente denominado 2019-nCoV, ahora designado SARS-CoV2) en bases de datos públicas y privadas, de protocolos diagnósticos estandarizados y de la información clínica epidemiológica generada permitirá atender la Emergencia de Salud Pública de Importancia Internacional (ESPII) declarada el 30 de enero por la OMS. Con este documento pretendemos aportar a la caracterización de la epidemia de neumonía, ahora llamada enfermedad por coronavirus (Covid-19), revisar las fortalezas que tiene México en el concierto de la salud global e invitar a los profesionales de la salud a incorporarse a las actividades de preparación y respuesta ante esta emergencia.


Subject(s)
Betacoronavirus , Coronavirus Infections/epidemiology , Disease Outbreaks , Pneumonia, Viral/epidemiology , COVID-19 , Global Health , Humans , Mexico , Pandemics , Public Health , SARS-CoV-2 , World Health Organization
9.
Gac. méd. Méx ; 156(2): 133-138, mar.-abr. 2020. graf
Article in English, Spanish | LILACS | ID: biblio-1249883

ABSTRACT

Resumen El 31 de diciembre de 2019, las autoridades chinas de salud informaron a la comunidad internacional, a través de los mecanismos establecidos por la Organización Mundial de la Salud (OMS), de una epidemia de neumonía con etiología desconocida en Wuhan, provincia de Hubei. Los primeros casos se notificaron a inicios de ese mes y se vincularon al antecedente de visitar un mercado de comida y animales vivos. El 7 de enero de 2020 se logró el aislamiento y reconocimiento del patógeno responsable mediante secuenciación de siguiente generación, mientras el número de afectados continuaba en ascenso. La publicación de genomas completos del nuevo coronavirus identificado (inicialmente denominado 2019-nCoV, ahora designado SARS-CoV2) en bases de datos públicas y privadas, de protocolos diagnósticos estandarizados y de la información clínica epidemiológica generada permitirá atender la Emergencia de Salud Pública de Importancia Internacional (ESPII) declarada el 30 de enero por la OMS. Con este documento pretendemos aportar a la caracterización de la epidemia de neumonía, ahora llamada enfermedad por coronavirus (Covid-19), revisar las fortalezas que tiene México en el concierto de la salud global e invitar a los profesionales de la salud a incorporarse a las actividades de preparación y respuesta ante esta emergencia.


Abstract On December 31, 2019, the Chinese health authorities informed the international community, through the mechanisms established by the World Health Organization (WHO), of a pneumonia epidemic of unknown etiology in Wuhan, Hubei Province. The first cases were reported early in that month and were linked to a history of having visited a market where food and live animals are sold. On January 7, 2020, isolation and identification of the culprit pathogen was achieved using next-generation sequencing, while the number of affected subjects continued to rise. The publication of full-genomes of the newly identified coronavirus (initially called 2019-nCoV, now designated SARS-CoV2) in public and private databases, of standardized diagnostic protocols and of the clinical-epidemiological information generated will allow addressing the Public Health Emergency of International Concern (PHEIC), declared on January 30 by the WHO. With this document, we intend to contribute to the characterization of the pneumonia epidemic, now called Corona virus disease (Covid-19) review the strengths Mexico has in the global health concert and invite health professionals to join the preparedness and response activities in the face of this emergency.


Subject(s)
Humans , Pneumonia, Viral/epidemiology , Disease Outbreaks , Coronavirus Infections/epidemiology , Betacoronavirus , World Health Organization , Public Health , Global Health , Pandemics , SARS-CoV-2 , COVID-19 , Mexico
10.
Rev. salud pública ; 22(2): e214, mar.-abr. 2020. graf
Article in Spanish | LILACS | ID: biblio-1139443

ABSTRACT

RESUMEN Objetivo Estimar el intervalo serial y el número básico de reproducción de COVID-19 entre casos importados durante la fase de contención en Pereira, Colombia, 2020. Método Se realizó un estudio cuantitativo para determinar algunos aspectos de la dinámica de transmisión de la COVID-19. Se utilizaron las entrevistas epidemiológicas de campo en los que se incluyeron 12 casos confirmados por laboratorio con PCR-RT para SARS-CoV-2 importados y sus correspondientes casos secundarios confirmados, entre los que estaban contactos familiares y sociales. Resultados Los intervalos seriales en la COVID-19 se ajustan a una distribución Gamma, con una media del intervalo serial de 3,8 días (± 2,7) y un R0 de 1,7 (IC 95% 1,06-2,7) inferior a lo encontrado en otras poblaciones con inicio del brote. Conclusiones Un intervalo serial inferior al periodo de incubación como el que se estimó en este estudio sugiere un periodo de transmisión presintomático que, según otras investigaciones, alcanza un pico promedio a los 3,8 días, hecho que sugiere que durante la investigación epidemiológica de campo la búsqueda de contactos estrechos se realice desde al menos 2 días antes del inicio de síntomas del caso inicial.(AU)


ABSTRACT Objective To estimate the serial interval and the basic reproduction number of COVID-19 between imported cases during the containment phase in Pereira-Colombia, 2020. Method A quantitative study was carried out to determine the transmission dynamics for COVID-19. Field epidemiological data were used, which included 12 laboratory-confirmed cases with RT-PCR for imported SARS-CoV-2 and their corresponding confirmed secondary cases, including family and social contacts. Results The serial intervals in COVID-19 fit a Gamma distribution, with a mean of the serial interval of 3.8 days (2.7) and an R0 of 1.7 (95% CI 1.06-2.7) lower than that found in other populations with onset of the outbreak. Conclusions A serial interval lower than the incubation period such as that estimated in this study, suggests a presymptomatic transmission period that according to other investigations reaches an average peak at 3.8 days, suggesting that during the field epidemiological investigation the search for contacts Narrowing is performed from at least 2 days before the onset of symptoms of the initial case.(AU)


Subject(s)
Humans , Coronavirus Infections/transmission , Basic Reproduction Number , Betacoronavirus , Cross-Sectional Studies/instrumentation , Colombia/epidemiology
11.
Rev Salud Publica (Bogota) ; 22(2): 194-197, 2020 03 01.
Article in Spanish | MEDLINE | ID: mdl-36753110

ABSTRACT

OBJECTIVE: To estimate the serial interval and the basic reproduction number of COVID-19 between imported cases during the containment phase in Pereira-Colombia, 2020. METHOD: A quantitative study was carried out to determine the transmission dynamics for COVID-19. Field epidemiological data were used, which included 12 laboratory-confirmed cases with RT-PCR for imported SARS-CoV-2 and their corresponding confirmed secondary cases, including family and social contacts. RESULTS: The serial intervals in COVID-19 fit a Gamma distribution, with a mean of the serial interval of 3.8 days (2.7) and an R0 of 1.7 (95% CI 1.06-2.7) lower than that found in other populations with onset of the outbreak. CONCLUSIONS: A serial interval lower than the incubation period such as that estimated in this study, suggests a presymptomatic transmission period that according to other investigations reaches an average peak at 3.8 days, suggesting that during the field epidemiological investigation the search for contacts Narrowing is performed from at least 2 days before the onset of symptoms of the initial case.


Subject(s)
COVID-19 , Humans , COVID-19/epidemiology , SARS-CoV-2 , Basic Reproduction Number , Disease Outbreaks , Colombia
12.
Arch Med Res ; 41(6): 478-82, 2010 Aug.
Article in English | MEDLINE | ID: mdl-21044753

ABSTRACT

An expandable vertebral body prosthesis with dual cage-and-plate function in a single device (JR prosthesis) was designed to test the hypothesis that this modular system can provide the biomechanical requirements for immediate and durable spine stabilization after corpectomy. Cadaver assays were performed with a stainless steal device to test fixation and adequacy to the human spine anatomy. Then, 14 patients with vertebral tumors (eight metastatic) underwent corpectomy and vertebral body replacement with a titanium-made JR prosthesis. All patients had neurological deficit, severe pain and spine instability prior to surgery. Mean pain score before surgery on a visual analog scale decreased from 7.6-3.0 points after operation (p = 0.002). All patients achieved at least one grade of improvement in the Frankel score (p = 0.003), excepting the three patients with Frankel grade A before surgery. Two patients with renal cell carcinoma died during the following 4 days after surgery. The remaining patients attained a painless and stable spine immediately, which was maintained for long periods (mean follow-up: 25.4 months). No significant infections or implant failures were registered. A nonfatal case of inferior vena cava surgical injury was observed (repaired during surgery without further complications). In conclusion, the JR prosthesis stabilizes the spine immediately after surgery and for the rest of the patients' life. To our knowledge, this is the first report on the clinical experience of any expandable vertebral body prosthesis with dual cage-and-plate function in a single device.


Subject(s)
Prostheses and Implants , Spinal Neoplasms/surgery , Adult , Aged , Child , Female , Humans , Lumbar Vertebrae/surgery , Male , Middle Aged , Prosthesis Design , Spinal Neoplasms/secondary , Thoracic Vertebrae/surgery , Titanium , Young Adult
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