Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
1.
Parasitol Res ; 122(3): 801-814, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36683088

RESUMEN

Aedes aegypti is an important vector of several arboviruses including dengue and chikungunya viruses. Accurate identification of larval habitats of Ae. aegypti is considered an essential step in targeted control. This study determined Ae. aegypti productivity in selected larval habitats in Msambweni, Kwale County, Kenya. Three sequential larval habitat surveys were conducted. The first survey was habitat census (baseline) through which 83 representative larval habitats were identified and selected. The second and third surveys involved estimating daily productivity of the 83 selected larval habitats for 30 consecutive days during a wet and a dry season, respectively. Of 664 larval habitats examined at baseline, 144 larval habitats (21.7%) were found to be infested with Ae. aegypti larvae. At baseline, majority (71%) of the pupae were collected from two (2/6) larval habitat types, tires and pots. Multivariate analysis identified habitat type and the habitat being movable as the predictors for pupal abundance. During the 30-day daily pupal production surveys, only a few of the habitats harbored pupae persistently. Pupae were found in 28% and 12% of the larval habitats during the wet and dry seasons, respectively. In the wet season, drums, tires, and pots were identified as the key habitat types accounting for 85% of all pupae sampled. Three habitats (all drums) accounted for 80% of all the pupae collected in the dry season. Predictors for pupal productivity in the wet season were habitat type, place (whether the habitat is located at the back or front of the house), habitat purpose (use of the water in the habitat), and source of water. Although the multivariate model for habitat type did not converge, habitat type and habitat size were the only significant predictors during the dry season. Drums, pots, and tires were sources of more than 85% of Ae. aegypti pupae, reinforcing the "key container concept." Targeting these three types of habitats makes epidemiological sense, especially during the dry season.


Asunto(s)
Aedes , Dengue , Animales , Pupa , Larva , Kenia , Mosquitos Vectores , Ecosistema , Estaciones del Año , Agua
2.
Int J Oral Maxillofac Surg ; 52(6): 703-709, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36220682

RESUMEN

Facial symmetry plays an important role in facial attractiveness and is one of the major criteria used to determine attractiveness in humans. In craniomaxillofacial surgery, facial symmetry is one of the main considerations. The aim of this study was to determine anthropometric measurements quantitatively and investigate the relationship between facial symmetry and attractiveness in a local Malay population. The study included 30 photographed Malay individuals and 100 photograph assessors, all aged between 18 and 26 years. The assessors indicated their preferences regarding the more attractive face on original and manipulated (symmetrical face) photographs. None of the photographed subjects had a perfectly symmetrical face (asymmetry index (AI) of 0%); 33.3% of the photographed subjects had an AI in the range of 1.6-2.0%. The majority of assessors chose the manipulated symmetrical face as the most attractive (manipulated photograph selected in 91.2% of cases). As facial symmetry is considered a critical factor in attractiveness, it is beneficial to consider balance and symmetry prior to facial reconstruction. The AI values found in this study may be useful as guidance to determine the normal minimum balance of facial symmetry. No AI values indicating perfect symmetry were observed for the unedited facial anthropometric measurements. However, the projection of a perfectly symmetrical face does influence the perception of facial attractiveness.


Asunto(s)
Belleza , Cara , Adolescente , Adulto , Humanos , Adulto Joven
3.
Front Mol Neurosci ; 15: 891463, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35557554

RESUMEN

Primary sensory axons in adult mammals fail to regenerate after spinal cord injury (SCI), in part due to insufficient intrinsic growth potential. Robustly boosting their growth potential continues to be a challenge. Previously, we showed that constitutive activation of B-RAF (rapidly accelerated fibrosarcoma kinase) markedly promotes axon regeneration after dorsal root and optic nerve injuries. The regrowth is further augmented by supplemental deletion of PTEN (phosphatase and tensin homolog). Here, we examined whether concurrent B-RAF activation and PTEN deletion promotes dorsal column axon regeneration after SCI. Remarkably, genetically targeting B-RAF and PTEN selectively in DRG neurons of adult mice enables many DC axons to enter, cross, and grow beyond the lesion site after SCI; some axons reach ∼2 mm rostral to the lesion by 3 weeks post-injury. Co-targeting B-RAF and PTEN promotes more robust DC regeneration than a pre-conditioning lesion, which additively enhances the regeneration triggered by B-RAF/PTEN. We also found that post-injury targeting of B-RAF and PTEN enhances DC axon regeneration. These results demonstrate that co-targeting B-RAF and PTEN effectively enhances the intrinsic growth potential of DC axons after SCI and therefore may help to develop a novel strategy to promote robust long-distance regeneration of primary sensory axons.

4.
Brain Sci ; 11(12)2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34942945

RESUMEN

Microglia are major players in scar formation after an injury to the spinal cord. Microglia proliferation, differentiation, and survival are regulated by the colony-stimulating factor 1 (CSF1). Complete microglia elimination using CSF1 receptor (CSF1R) inhibitors worsens motor function recovery after spinal injury (SCI). Conversely, a 1-week oral treatment with GW2580, a CSF1R inhibitor that only inhibits microglia proliferation, promotes motor recovery. Here, we investigate whether prolonged GW2580 treatment further increases beneficial effects on locomotion after SCI. We thus assessed the effect of a 6-week GW2580 oral treatment after lateral hemisection of the spinal cord on functional recovery and its outcome on tissue and cellular responses in adult mice. Long-term depletion of microglia proliferation after SCI failed to improve motor recovery and had no effect on tissue reorganization, as revealed by ex vivo diffusion-weighted magnetic resonance imaging. Six weeks after SCI, GW2580 treatment decreased microglial reactivity and increased astrocytic reactivity. We thus demonstrate that increasing the duration of GW2580 treatment is not beneficial for motor recovery after SCI.

5.
Med J Malaysia ; 76(4): 583-584, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34305124

RESUMEN

Cutaneous sporotrichosis (CS) presents as asymptomatic lesions of varied morphology. The most common variant is the lymphocutaneous type which typically progresses from a papule to an ulcer and then forms nodules along the superficial lymphatic channels. Diagnosis CS may be challenging when the lesion presents at an uncommon site where the superficial lymphatic drainage is unfamiliar. We present here a case of sporotrichosis of the abdominal wall which was initially misdiagnosed as an abscess but later confirmed by culture and managed successfully.


Asunto(s)
Pared Abdominal , Esporotricosis , Pared Abdominal/diagnóstico por imagen , Pared Abdominal/cirugía , Humanos , Esporotricosis/diagnóstico , Esporotricosis/tratamiento farmacológico
6.
Nat Commun ; 12(1): 3845, 2021 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-34158506

RESUMEN

Atr is a serine/threonine kinase, known to sense single-stranded DNA breaks and activate the DNA damage checkpoint by phosphorylating Chek1, which inhibits Cdc25, causing cell cycle arrest. This pathway has not been implicated in neuroregeneration. We show that in Drosophila sensory neurons removing Atr or Chek1, or overexpressing Cdc25 promotes regeneration, whereas Atr or Chek1 overexpression, or Cdc25 knockdown impedes regeneration. Inhibiting the Atr-associated checkpoint complex in neurons promotes regeneration and improves synapse/behavioral recovery after CNS injury. Independent of DNA damage, Atr responds to the mechanical stimulus elicited during regeneration, via the mechanosensitive ion channel Piezo and its downstream NO signaling. Sensory neuron-specific knockout of Atr in adult mice, or pharmacological inhibition of Atr-Chek1 in mammalian neurons in vitro and in flies in vivo enhances regeneration. Our findings reveal the Piezo-Atr-Chek1-Cdc25 axis as an evolutionarily conserved inhibitory mechanism for regeneration, and identify potential therapeutic targets for treating nervous system trauma.


Asunto(s)
Axones/metabolismo , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/genética , Canales Iónicos/genética , Regeneración Nerviosa/genética , Animales , Animales Modificados Genéticamente , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1)/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Células HEK293 , Humanos , Canales Iónicos/metabolismo , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal/genética
7.
Nat Commun ; 12(1): 1233, 2021 02 23.
Artículo en Inglés | MEDLINE | ID: mdl-33623008

RESUMEN

Climate drives population dynamics through multiple mechanisms, which can lead to seemingly context-dependent effects of climate on natural populations. For climate-sensitive diseases, such as dengue, chikungunya, and Zika, climate appears to have opposing effects in different contexts. Here we show that a model, parameterized with laboratory measured climate-driven mosquito physiology, captures three key epidemic characteristics across ecologically and culturally distinct settings in Ecuador and Kenya: the number, timing, and duration of outbreaks. The model generates a range of disease dynamics consistent with observed Aedes aegypti abundances and laboratory-confirmed arboviral incidence with variable accuracy (28-85% for vectors, 44-88% for incidence). The model predicted vector dynamics better in sites with a smaller proportion of young children in the population, lower mean temperature, and homes with piped water and made of cement. Models with limited calibration that robustly capture climate-virus relationships can help guide intervention efforts and climate change disease projections.


Asunto(s)
Cambio Climático , Geografía , Enfermedades Transmitidas por Vectores/epidemiología , Enfermedades Transmitidas por Vectores/transmisión , Animales , Número Básico de Reproducción , Culicidae/fisiología , Brotes de Enfermedades , Ecuador/epidemiología , Humanos , Kenia/epidemiología , Modelos Biológicos , Dinámicas no Lineales , Factores Socioeconómicos , Análisis Espacio-Temporal , Factores de Tiempo
8.
Br J Dermatol ; 184(6): 1014-1022, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32974943

RESUMEN

Optical coherence tomography (OCT) is a noninvasive optical imaging method that can generate high-resolution en face and cross-sectional images of the skin in vivo to a maximum depth of 2 mm. While OCT holds considerable potential for noninvasive diagnosis and disease monitoring, it is poorly understood by many dermatologists. Here we aim to equip the practising dermatologist with an understanding of the principles of skin OCT and the potential clinical indications. We begin with an introduction to the technology and discuss the different modalities of OCT including angiographic (dynamic) OCT, which can image cutaneous blood vessels at high resolution. Next we review clinical applications. OCT has been most extensively investigated in the diagnosis of keratinocyte carcinomas, particularly basal cell carcinoma. To date, OCT has not proven sufficiently accurate for the robust diagnosis of malignant melanoma; however, the evaluation of abnormal vasculature with angiographic OCT is an area of active investigation. OCT, and in particular angiographic OCT, also shows promise in monitoring the response to therapy of inflammatory dermatoses, such as psoriasis and connective tissues disease. We additionally discuss a potential role for artificial intelligence in improving the accuracy of interpretation of OCT imaging data.


Asunto(s)
Dermatología , Neoplasias Cutáneas , Inteligencia Artificial , Estudios Transversales , Humanos , Neoplasias Cutáneas/diagnóstico por imagen , Tomografía de Coherencia Óptica
9.
Parasit Vectors ; 13(1): 499, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33004074

RESUMEN

BACKGROUND: Aedes aegypti is an efficient vector of several arboviruses of public health importance, including Zika and dengue. Currently vector management is the only available avenue for disease control. Development of efficient vector control strategies requires a thorough understanding of vector ecology. In this study, we identified households that are consistently productive for Ae. aegypti pupae and determined the ecological and socio-demographic factors associated with the persistence and abundance of pupae in households in rural and urban Kenya. METHODS: We collected socio-demographic, environmental and entomological data monthly from July 2014 to June 2018 from 80 households across four sites in Kenya. Pupae count data were collected via entomological surveillance of households and paired with socio-demographic and environmental data. We calculated pupal persistence within a household as the number of months of pupal presence within a year. We used spatially explicit generalized additive mixed models (GAMMs) to identify the risk factors for pupal abundance, and a logistic regression to identify the risk factors for pupal persistence in households. RESULTS: The median number of months of pupal presence observed in households was 4 and ranged from 0 to 35 months. We identified pupal persistence in 85 house-years. The strongest risk factors for high pupal abundance were the presence of bushes or tall grass in the peri-domicile area (OR: 1.60, 95% CI: 1.13-2.28), open eaves (OR: 2.57, 95% CI: 1.33-4.95) and high habitat counts (OR: 1.42, 95% CI: 1.21-1.66). The main risk factors for pupal persistence were the presence of bushes or tall grass in the peri-domicile (OR: 4.20, 95% CI: 1.42-12.46) and high number of breeding sites (OR: 2.17, 95% CI: 1.03-4.58). CONCLUSIONS: We observed Ae. aegypti pupal persistence at the household level in urban and rural and in coastal and inland Kenya. High counts of potential breeding containers, vegetation in the peri-domicile area and the presence of eaves were strongly associated with increased risk of pupal persistence and abundance. Targeting households that exhibit pupal persistence alongside the risk factors for pupal abundance in vector control interventions may result in more efficient use of limited resources.


Asunto(s)
Aedes/fisiología , Mosquitos Vectores/fisiología , Pupa/crecimiento & desarrollo , Aedes/crecimiento & desarrollo , Distribución Animal , Animales , Ecosistema , Entomología , Composición Familiar , Femenino , Humanos , Kenia , Masculino , Control de Mosquitos , Mosquitos Vectores/crecimiento & desarrollo , Pupa/fisiología , Población Rural
10.
Cell Metab ; 32(5): 767-785.e7, 2020 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-32941799

RESUMEN

Axons in the mature central nervous system (CNS) fail to regenerate after axotomy, partly due to the inhibitory environment constituted by reactive glial cells producing astrocytic scars, chondroitin sulfate proteoglycans, and myelin debris. We investigated this inhibitory milieu, showing that it is reversible and depends on glial metabolic status. We show that glia can be reprogrammed to promote morphological and functional regeneration after CNS injury in Drosophila via increased glycolysis. This enhancement is mediated by the glia derived metabolites: L-lactate and L-2-hydroxyglutarate (L-2HG). Genetically/pharmacologically increasing or reducing their bioactivity promoted or impeded CNS axon regeneration. L-lactate and L-2HG from glia acted on neuronal metabotropic GABAB receptors to boost cAMP signaling. Local application of L-lactate to injured spinal cord promoted corticospinal tract axon regeneration, leading to behavioral recovery in adult mice. Our findings revealed a metabolic switch to circumvent the inhibition of glia while amplifying their beneficial effects for treating CNS injuries.


Asunto(s)
Sistema Nervioso Central/metabolismo , Neuroglía/metabolismo , Animales , Drosophila melanogaster , Femenino , Ratones , Ratones Endogámicos C57BL , Regeneración Nerviosa
11.
Med J Malaysia ; 75(4): 439-441, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32724012

RESUMEN

Ankyloglossia is a congenital anomaly which may reduce or restrict the tongue tip mobility. The restricted mobility is caused by an unusual short, thick lingual frenum. This condition may cause various problems in infants including breastfeeding in the new-borns. This case report describes 3 cases of ankyloglossia affecting breastfeeding and highlights the experiences of the mothers and their difficulties in breastfeeding babies with it. Comprehensive feeding examination was accomplished, the primary cause of feeding issues was identified, and frenotomy intervention was provided. Post frenotomy, infants were able to breastfeed easily and this was beneficial in continuation of breastfeeding and pain reduction in mothers.


Asunto(s)
Anquiloglosia/fisiopatología , Anquiloglosia/cirugía , Lactancia Materna , Anomalías de la Boca/cirugía , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Resultado del Tratamiento
12.
PLoS Negl Trop Dis ; 14(6): e0008362, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32559197

RESUMEN

Arboviruses are among the most important emerging pathogens due to their increasing public health impact. In Kenya, continued population growth and associated urbanization are conducive to vector spread in both urban and rural environments, yet mechanisms of viral amplification in vector populations is often overlooked when assessing risks for outbreaks. Thus, the characterization of local arbovirus circulation in mosquito populations is imperative to better inform risk assessments and vector control practices. Aedes species mosquitoes were captured at varying stages of their life cycle during different seasons between January 2014 and May 2016 at four distinct sites in Kenya, and tested for chikungunya (CHIKV), dengue (DENV) and Zika (ZIKV) viruses by RT-PCR. CHIKV was detected in 45 (5.9%) and DENV in 3 (0.4%) mosquito pools. No ZIKV was detected. Significant regional variation in prevalence was observed, with greater frequency of CHIKV on the coast. DENV was detected exclusively on the coast. Both viruses were detected in immature mosquitoes of both sexes, providing evidence of transovarial transmission of these arboviruses in local mosquitoes. This phenomenon may be driving underlying viral maintenance that may largely contribute to periodic re-emergence among humans in Kenya.


Asunto(s)
Fiebre Chikungunya/transmisión , Virus Chikungunya/aislamiento & purificación , Culicidae/virología , Virus del Dengue/aislamiento & purificación , Dengue/transmisión , Aedes/fisiología , Aedes/virología , Animales , Arbovirus , Fiebre Chikungunya/epidemiología , Fiebre Chikungunya/virología , Culicidae/fisiología , Dengue/epidemiología , Dengue/virología , Femenino , Humanos , Kenia/epidemiología , Estadios del Ciclo de Vida , Masculino , Virus Zika , Infección por el Virus Zika/virología
13.
Stem Cell Reports ; 12(5): 1159-1177, 2019 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-31031189

RESUMEN

Anamniotes, rodents, and young humans maintain neural stem cells in the ependymal zone (EZ) around the central canal of the spinal cord, representing a possible endogenous source for repair in mammalian lesions. Cell diversity and genes specific for this region are ill defined. A cellular and molecular resource is provided here for the mouse and human EZ based on RNA profiling, immunostaining, and fluorescent transgenic mice. This uncovered the conserved expression of 1,200 genes including 120 transcription factors. Unexpectedly the EZ maintains an embryonic-like dorsal-ventral pattern of expression of spinal cord developmental transcription factors (ARX, FOXA2, MSX1, and PAX6). In mice, dorsal and ventral EZ cells express Vegfr3 and are derived from the embryonic roof and floor plates. The dorsal EZ expresses a high level of Bmp6 and Gdf10 genes and harbors a subpopulation of radial quiescent cells expressing MSX1 and ID4 transcription factors.


Asunto(s)
Células Madre Embrionarias/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación del Desarrollo de la Expresión Génica , ARN/genética , Médula Espinal/metabolismo , Células Madre/metabolismo , Animales , Células Madre Embrionarias/citología , Células Ependimogliales/citología , Células Ependimogliales/metabolismo , Femenino , Humanos , Factor de Transcripción MSX1/genética , Factor de Transcripción MSX1/metabolismo , Masculino , Ratones , Ratones Transgénicos , Microscopía Fluorescente , Persona de Mediana Edad , Células-Madre Neurales/citología , Células-Madre Neurales/metabolismo , ARN/metabolismo , Médula Espinal/citología , Nicho de Células Madre , Células Madre/citología , Adulto Joven
14.
J Neurotrauma ; 35(24): 2924-2940, 2018 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-29877129

RESUMEN

Spinal cord injuries (SCI) are disastrous neuropathologies causing permanent disabilities. The availability of different strains of mice is valuable for studying the pathophysiological mechanisms involved in SCI. However, strain differences have a profound effect on spontaneous functional recovery after SCI. CX3CR1+/eGFP and Aldh1l1-EGFP mice that express green fluorescent protein in microglia/monocytes and astrocytes, respectively, are particularly useful to study glial reactivity. Whereas CX3CR1+/eGFP mice have C57BL/6 background, Aldh1l1-EGFP are in Swiss Webster background. We first assessed spontaneous functional recovery in CX3CR1+/eGFP and Aldh1l1-EGFP mice over 6 weeks after lateral spinal cord hemisection. Second, we carried out a longitudinal follow-up of lesion evolution using in vivo T2-weighted magnetic resonance imaging (MRI). Finally, we performed in-depth analysis of the spinal cord tissue using ex vivo T2-weighted MRI as well as detailed histology. We demonstrate that CX3CR1+/eGFP mice have improved functional recovery and reduced anxiety after SCI compared with Aldh1l1-EGFP mice. We also found a strong correlation between in vivo MRI, ex vivo MRI, and histological analyses of the injured spinal cord in both strain of mice. All three modalities revealed no difference in lesion extension and volume between the two strains of mice. Importantly, histopathological analysis identified decreased gliosis and increased serotonergic axons in CX3CR1+/eGFP compared with Aldh1l1-EGFP mice following SCI. These results thus suggest that the strain-dependent improved functional recovery after SCI may be linked with reduced gliosis and increased serotonergic innervation.


Asunto(s)
Gliosis/patología , Recuperación de la Función/fisiología , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/fisiopatología , Animales , Estudios Longitudinales , Imagen por Resonancia Magnética , Ratones , Ratones Endogámicos C57BL
15.
Neurotherapeutics ; 15(3): 751-769, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29181770

RESUMEN

Spinal cord injuries (SCI) lead to major disabilities affecting > 2.5 million people worldwide. Major shortcomings in clinical translation result from multiple factors, including species differences, development of moderately predictive animal models, and differences in methodologies between preclinical and clinical studies. To overcome these obstacles, we first conducted a comparative neuroanatomical analysis of the spinal cord between mice, Microcebus murinus (a nonhuman primate), and humans. Next, we developed and characterized a new model of lateral spinal cord hemisection in M. murinus. Over a 3-month period after SCI, we carried out a detailed, longitudinal, behavioral follow-up associated with in vivo magnetic resonance imaging (1H-MRI) monitoring. Then, we compared lesion extension and tissue alteration using 3 methods: in vivo 1H-MRI, ex vivo 1H-MRI, and classical histology. The general organization and glial cell distribution/morphology in the spinal cord of M. murinus closely resembles that of humans. Animals assessed at different stages following lateral hemisection of the spinal cord presented specific motor deficits and spinal cord tissue alterations. We also found a close correlation between 1H-MRI signal and microglia reactivity and/or associated post-trauma phenomena. Spinal cord hemisection in M. murinus provides a reliable new nonhuman primate model that can be used to promote translational research on SCI and represents a novel and more affordable alternative to larger primates.


Asunto(s)
Modelos Animales de Enfermedad , Traumatismos de la Médula Espinal/patología , Traumatismos de la Médula Espinal/fisiopatología , Investigación Biomédica Traslacional/métodos , Animales , Proteínas de Unión al Calcio , Cheirogaleidae , Proteínas de Unión al ADN/metabolismo , Conducta Exploratoria , Femenino , Estudios de Seguimiento , Lateralidad Funcional , Proteína Ácida Fibrilar de la Glía/metabolismo , Humanos , Imagen por Resonancia Magnética , Masculino , Ratones , Proteínas de Microfilamentos , Microglía/patología , Persona de Mediana Edad , Fuerza Muscular/fisiología , Unión Neuromuscular/patología , Desempeño Psicomotor/fisiología , Especificidad de la Especie , Médula Espinal/patología , Factores de Tiempo , Tritio
16.
Front Aging Neurosci ; 9: 230, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28769787

RESUMEN

Central nervous system (CNS) injury has been observed to lead to microglia activation and monocytes infiltration at the lesion site. Ex vivo diffusion magnetic resonance imaging (diffusion MRI or DWI) allows detailed examination of CNS tissues, and recent advances in clearing procedures allow detailed imaging of fluorescent-labeled cells at high resolution. No study has yet combined ex vivo diffusion MRI and clearing procedures to establish a possible link between microglia/monocytes response and diffusion coefficient in the context of spinal cord injury (SCI). We carried out ex vivo MRI of the spinal cord at different time-points after spinal cord transection followed by tetrahydrofuran based clearing and examined the density and morphology of microglia/monocytes using two-photon microscopy. Quantitative analysis revealed an early marked increase in microglial/monocytes density that is associated with an increase in the extension of the lesion measured using diffusion MRI. Morphological examination of microglia/monocytes somata at the lesion site revealed a significant increase in their surface area and volume as early as 72 hours post-injury. Time-course analysis showed differential microglial/monocytes response rostral and caudal to the lesion site. Microglia/monocytes showed a decrease in reactivity over time caudal to the lesion site, but an increase was observed rostrally. Direct comparison of microglia/monocytes morphology, obtained through multiphoton, and the longitudinal apparent diffusion coefficient (ADC), measured with diffusion MRI, highlighted that axonal integrity does not correlate with the density of microglia/monocytes or their somata morphology. We emphasize that differential microglial/monocytes reactivity rostral and caudal to the lesion site may thus coincide, at least partially, with reported temporal differences in debris clearance. Our study demonstrates that the combination of ex vivo diffusion MRI and two-photon microscopy may be used to follow structural tissue alteration. Lesion extension coincides with microglia/monocytes density; however, a direct relationship between ADC and microglia/monocytes density and morphology was not observed. We highlighted a differential rostro-caudal microglia/monocytes reactivity that may correspond to a temporal difference in debris clearance and axonal integrity. Thus, potential therapeutic strategies targeting microglia/monocytes after SCI may need to be adjusted not only with the time after injury but also relative to the location to the lesion site.

17.
Front Aging Neurosci ; 9: 227, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28785215

RESUMEN

Over the last decade, microglia have been acknowledged to be key players in central nervous system (CNS) under both physiological and pathological conditions. They constantly survey the CNS environment and as immune cells, in pathological contexts, they provide the first host defense and orchestrate the immune response. It is well recognized that under pathological conditions microglia have both sequential and simultaneous, beneficial and detrimental effects. Cell-specific transcriptomics recently became popular in Neuroscience field allowing concurrent monitoring of the expression of numerous genes in a given cell population. Moreover, by comparing two or more conditions, these approaches permit to unbiasedly identify deregulated genes and pathways. A growing number of studies have thus investigated microglial transcriptome remodeling over the course of neuropathological conditions and highlighted the molecular diversity of microglial response to different diseases. In the present work, we restrict our review to microglia obtained directly from in vivo samples and not cell culture, and to studies using whole-genome strategies. We first critically review the different methods developed to decipher microglia transcriptome. In particular, we compare advantages and drawbacks of flow cytometry and laser microdissection to isolate pure microglia population as well as identification of deregulated microglial genes obtained via RNA sequencing (RNA-Seq) vs. microarrays approaches. Second, we summarize insights obtained from microglia transcriptomes in traumatic brain and spinal cord injuries, pain and more chronic neurological conditions including Amyotrophic lateral sclerosis (ALS), Alzheimer disease (AD) and Multiple sclerosis (MS). Transcriptomic responses of microglia in other non-neurodegenerative CNS disorders such as gliomas and sepsis are also addressed. Third, we present a comparison of the most activated pathways in each neuropathological condition using Gene ontology (GO) classification and highlight the diversity of microglia response to insults focusing on their pro- and anti-inflammatory signatures. Finally, we discuss the potential of the latest technological advances, in particular, single cell RNA-Seq to unravel the individual microglial response diversity in neuropathological contexts.

18.
Parasit Vectors ; 10(1): 331, 2017 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-28701194

RESUMEN

BACKGROUND: Aedes aegypti, the principal vector for dengue and other emerging arboviruses, breeds preferentially in various man-made and natural container habitats. In the absence of vaccine, epidemiological surveillance and vector control remain the best practices for preventing dengue outbreaks. Effective vector control depends on a good understanding of larval and adult vector ecology of which little is known in Kenya. In the current study, we sought to characterize breeding habitats and establish container productivity profiles of Ae. aegypti in rural and urban sites in western and coastal Kenya. METHODS: Twenty sentinel houses in each of four study sites (in western and coastal Kenya) were assessed for immature mosquito infestation once a month for a period of 24 months (June 2014 to May 2016). All water-holding containers in and around the households were inspected for Ae. aegypti larvae and pupae. RESULTS: Collections were made from a total of 22,144 container visits: Chulaimbo (7575) and Kisumu (8003) in the west, and from Msambweni (3199) and Ukunda (3367) on the coast. Of these, only 4-5.6% were positive for Ae. aegypti immatures. In all four sites, significantly more positive containers were located outdoors than indoors. A total of 17,537 Ae. aegypti immatures were sampled from 10 container types. The most important habitat types were buckets, drums, tires, and pots, which produced over 75% of all the pupae. Key outdoor containers in the coast were buckets, drums and tires, which accounted for 82% of the pupae, while pots and tires were the only key containers in the western region producing 70% of the pupae. Drums, buckets and pots were the key indoor containers, producing nearly all of the pupae in the coastal sites. No pupae were collected indoors in the western region. The coastal region produced significantly more Ae. aegypti immatures than the western region both inside and outside the sentinel houses. CONCLUSIONS: These results indicate that productive Ae. aegypti larval habitats are abundant outdoors and that only a few containers produce a majority of the pupae. Although the numbers were lower, productive habitats were detected within households. Targeting source reduction efforts towards these productive containers both inside and outside homes is likely to be a cost-effective way to reduce arboviral transmission in these regions.


Asunto(s)
Aedes/fisiología , Dengue/transmisión , Brotes de Enfermedades , Insectos Vectores/fisiología , Control de Mosquitos , Aedes/virología , Animales , Cruzamiento , Dengue/virología , Ecología , Ecosistema , Femenino , Insectos Vectores/virología , Kenia/epidemiología , Larva , Masculino , Pupa
19.
Front Mol Neurosci ; 10: 90, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28420963

RESUMEN

Neurons have inherent competence to regrow following injury, although not spontaneously. Spinal cord injury (SCI) induces a pronounced neuroinflammation driven by resident microglia and infiltrating peripheral macrophages. Microglia are the first reactive glial population after SCI and participate in recruitment of monocyte-derived macrophages to the lesion site. Both positive and negative influence of microglia and macrophages on axonal regeneration had been reported after SCI, raising the issue whether their response depends on time post-lesion or different lesion severity. We analyzed molecular alterations in microglia at several time-points after different SCI severities using RNA-sequencing. We demonstrate that activation of microglia is time-dependent post-injury but is independent of lesion severity. Early transcriptomic response of microglia after SCI involves proliferation and neuroprotection, which is then switched to neuroinflammation at later stages. Moreover, SCI induces an autologous microglial expression of astrocytic markers with over 6% of microglia expressing glial fibrillary acidic protein and vimentin from as early as 72 h post-lesion and up to 6 weeks after injury. We also identified the potential involvement of DNA damage and in particular tumor suppressor gene breast cancer susceptibility gene 1 (Brca1) in microglia after SCI. Finally, we established that BRCA1 protein is specifically expressed in non-human primate spinal microglia and is upregulated after SCI. Our data provide the first transcriptomic analysis of microglia at multiple stages after different SCI severities. Injury-induced microglia expression of astrocytic markers at RNA and protein levels demonstrates novel insights into microglia plasticity. Finally, increased microglia expression of BRCA1 in rodents and non-human primate model of SCI, suggests the involvement of oncogenic proteins after CNS lesion.

20.
BMJ Open ; 7(3): e010807, 2017 03 06.
Artículo en Inglés | MEDLINE | ID: mdl-28264822

RESUMEN

OBJECTIVE: To observe the influences on clinicians when discharging patients, to explore patients' perspectives concerning their discharge or follow-up decision and to identify what patients think is important for clinicians to consider when taking a discharge decision. DESIGN: Qualitative study involving observations of consultations and semistructured interviews with outpatients. SETTING: National Health Service outpatient clinics at a university hospital secondary referral centre. PARTICIPANTS: 64 consultations were observed followed by 56 interviews with patients aged over 18 years. MAIN OUTCOME MEASURE: Analysis of patients' perspectives and expectations concerning whether or not they were discharged. RESULTS: 25 types of influences were observed to be influencing the discharge decision process. All 31 discharged patients appeared to accept the clinicians' decision; however, 10 (22%) of those patients later expressed disappointment. Patients' discontent was due to perceived clinicians' uncertainty in diagnosis (patients mentioning=2), poor acceptance of the diagnosis (2), disease not 'cured' (4), differing perception on medical needs (2), lack of concern for job demands (1), felt uninvolved in the decision-making (4), feeling rushed (3), prolonged open appointment (2), pushed to seek private care due to healthcare budget constraints (2), language barrier (1) and not keen to continue follow-up with general practitioner (2). Patients were happy when there was certainty of the diagnosis (19), clear treatment plan (16), advised on treatment side effects (7), given a contact number if symptoms recurred (4), considering their travelling and job demands (3). CONCLUSIONS: This study highlights the importance of accurately perceiving patients' perspectives in ensuring the appropriateness of outpatient discharge. There was a disparity between patients' and clinicians' perception on what was an appropriate discharge. This included discrepancies concerning diagnostic certainties, private healthcare as an alternative, need for easy reaccess and choice of words surrounding discharge. Medical education should include handling these issues.


Asunto(s)
Competencia Clínica/estadística & datos numéricos , Toma de Decisiones Clínicas/métodos , Pacientes Ambulatorios/estadística & datos numéricos , Alta del Paciente/estadística & datos numéricos , Satisfacción del Paciente/estadística & datos numéricos , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Investigación Cualitativa , Derivación y Consulta , Gales
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...