An Improved Model for Circular RNA Overexpression: Using the Actin Intron Reveals High Circularization Efficiency.

Traditionally, the group 1 intron of the T4 td gene is used to generate a foreign circular sequence. However, the T4 system has been shown to be fairly inefficient in expressing circular RNA (circRNA). Here, a new method is developed to express circular sequences with high circularization efficiency to strengthen the confidence for future circRNA functional studies. CircRNA expression plasmids, constructed with different lengths derived from the actin intron (15-nt, 30-nt, 60-nt, 100-nt, 180-nt) and T4 intron, are introduced into human and mouse cell lines 293T and B16. Junction detection and sequencing are used to determine successful circularization of introns and their expression efficiencies. An actin intron with a medium length (60-nt-100-nt) shows significantly increased efficiency of circularization, whereas intron-100-nt shows the best efficiency in most conditions. RNA pull-down assays are designed to precipitate the splicing factors that are bound to the introns and intron/exon junction. The precipitated proteins are analyzed by mass spectrometry (MS), aiming to identify the possible underlying mechanism behind the high circularization efficiency. This expression system has been validated using different circRNAs, and such method shows potential in contributing to the expanding field of circRNA studies.

Mercury intoxication and ophthalmic involvement: An update review.

Human intoxication after mercury exposure is a rare condition that can cause severe damage to the central nervous, respiratory, cardiovascular, renal, gastrointestinal, skin, and visual systems and represents a major public health concern. Ophthalmic involvement includes impaired function of the extraocular muscles and the eyelids, as well as structural changes in the ocular surface, lens, retina, and optic nerve causing a potential irreversible damage to the visual system. Although, there are many pathways for poisoning depending on the mercury form, it has been suggested that tissue distribution does not differ in experimental animals when administered as mercury vapor, organic mercury, or inorganic mercury. Additionally, visual function alterations regarding central visual acuity, color discrimination, contrast sensitivity, visual field and electroretinogram responses have also been described widely. Nevertheless, there is still controversy about whether visual manifestations occur secondary to brain damage or as a direct affectation, and which ocular structure is primarily affected. Despite the use of some imaging techniques such as in vivo confocal microscopy of the cornea, optical coherence tomography (OCT) of the retina and optic nerve, and functional tests such as electroretinography has helped to solve in part this debate, further studies incorporating other imaging modalities such as autofluorescence, OCT angiography or adaptive optics retinal imaging are needed. This review aims to summarize the published structural and functional alterations found in the visual system of patients suffering from mercury intoxication.

Dolor lumbar: revisión y evidencia de tratamiento / Low back pain: review and evidence of treatment

El dolor lumbar corresponde a uno de los síntomas más prevalentes en la humanidad, siendo la segunda causa más frecuente de atención médica a nivel mundial. Existen diversos enfoques de diagnóstico y tratamiento para dolor lumbar, entre ellos la temporalidad del síntoma, el trabajo de diagnóstico sindromático, los síntomas de alarma, también llamados "banderas rojas", que pueden hacer sospechar patologías de mayor gravedad o urgencia. El estudio etiológico puede ser necesario en casos agudos con estas banderas rojas y en casos crónicos. Este estudio se realiza principalmente con imágenes (radiografías, tomografía computada, resonancia magnética, SPECT/CT) y ocasionalmente con exámenes de laboratorio. La mayor parte de los tratamientos están enfocados en el manejo conservador, principalmente el ejercicio físico guiado y asociado a fármacos analgésicos. Existen terapias alternativas tales como la acupuntura, el tai-chi, entre otros, algunas de ellas han mostrado ser un buen complemento al manejo del dolor lumbar. El enfoque multidisciplinario es la tendencia más actual de manejo, esto incluye el trabajo e intervención de diversos profesionales abordando el problema de forma integral, incluyendo el manejo psicoterapéutico. Intervenciones como las infiltraciones de columna han demostrado reducir el dolor por tiempos cortos, siendo útiles como puente para realizar un tratamiento apropiado. La cirugía solo se reserva para casos refractarios, siendo controversiales los resultados existentes en la literatura.

Low back pain is one of the most prevalent symptoms in humanity, being the second most common cause of medical attention worldwide. There are various approaches to diagnosis and treatment for low back pain, including the temporality of the symptom, the work of syndromatic diagnosis, the alarm symptoms, also called "red flags", that can make suspect pathologies of greater severity or emergency. The etiological study may be necessary in acute cases with these "red flags" and in chronic cases. This study is mainly done with images (X-rays, CT scan, MRI, SPECT/CT) and occasionally with laboratory tests. Most of the treatments are focused on conservative management, mainly guided physical exercise associated with analgesic drugs. There are alternative therapies such as acupuncture, tai-chi, among others, some of them have proven to be a good complement to the management of low back pain. The multidisciplinary approach is the most current management trend, this includes the work and intervention of various professionals addressing the problem in an integral way, including psychotherapeutic management. Interventions such as spinal infiltrations have been shown to reduce pain for short times, being useful as a bridge for proper treatment. Surgery is only reserved for refractory cases, the results existing in the literature being controversial.

Escala de autoeficacia general: reevaluación de su evidencia de confiabilidad y validez en Chile

Background: Self-efficacy is a psychological variable closely related to healthy behaviors. One of the most widely used instruments to measure this variable is the general self-efficacy scale (GSES). In Chile, the only psychometric study of this scale has important analytical limitations. Aim: To assess reliability and validity of GSES in a large Chilean sample. Material and Methods: The GSES and a self-esteem scale were applied to 2995 participants aged 11 to 76 years (60% women). Results: The scale showed optimal levels of homogeneity and internal consistency. The exploratory factor analysis and the parallel analysis suggested a one-dimensional internal structure. However, this model showed a mediocre fit in the confirmatory factor analysis due to the residual correlation between a pair of items with high semantic similarity. A one-dimensional model specifying this residual correlation attained an acceptable fit in a new confirmatory factor analysis. The new model reached strict invariance according to sex, and partial strict invariance according to age. The latent factor of the GSES showed a positive association with the latent factor of a self-esteem scale. Conclusions: The GSES is an adequate scale to measure general self-efficacy in the Chilean population and allows unbiased comparisons based on sex or age.

[The general self-efficacy scale (GSES): Reevaluation of its reliability and validity evidence in Chile]. / Escala de autoeficacia general: reevaluación de su evidencia de confiabilidad y validez en Chile.

BACKGROUND: Self-efficacy is a psychological variable closely related to healthy behaviors. One of the most widely used instruments to measure this variable is the general self-efficacy scale (GSES). In Chile, the only psychometric study of this scale has important analytical limitations. AIM: To assess reliability and validity of GSES in a large Chilean sample. MATERIAL AND METHODS: The GSES and a self-esteem scale were applied to 2995 participants aged 11 to 76 years (60% women). RESULTS: The scale showed optimal levels of homogeneity and internal consistency. The exploratory factor analysis and the parallel analysis suggested a one-dimensional internal structure. However, this model showed a mediocre fit in the confirmatory factor analysis due to the residual correlation between a pair of items with high semantic similarity. A one-dimensional model specifying this residual correlation attained an acceptable fit in a new confirmatory factor analysis. The new model reached strict invariance according to sex, and partial strict invariance according to age. The latent factor of the GSES showed a positive association with the latent factor of a self-esteem scale. CONCLUSIONS: The GSES is an adequate scale to measure general self-efficacy in the Chilean population and allows unbiased comparisons based on sex or age.

Plastid genomes reveal support for deep phylogenetic relationships and extensive rate variation among palms and other commelinid monocots.

Despite progress based on multilocus, phylogenetic studies of the palms (order Arecales, family Arecaceae), uncertainty remains in resolution/support among major clades and for the placement of the palms among the commelinid monocots. Palms and related commelinids represent a classic case of substitution rate heterogeneity that has not been investigated in the genomic era. To address questions of relationships, support and rate variation among palms and commelinid relatives, 39 plastomes representing the palms and related family Dasypogonaceae were generated via genome skimming and integrated within a monocot-wide matrix for phylogenetic and molecular evolutionary analyses. Support was strong for 'deep' relationships among the commelinid orders, among the five palm subfamilies, and among tribes of the subfamily Coryphoideae. Additionally, there was extreme heterogeneity in the plastid substitution rates across the commelinid orders indicated by model based analyses, with c. 22 rate shifts, and significant departure from a global clock. To date, this study represents the most comprehensively sampled matrix of plastomes assembled for monocot angiosperms, providing genome-scale support for phylogenetic relationships of monocot angiosperms, and lays the phylogenetic groundwork for comparative analyses of the drivers and correlates of such drastic differences in substitution rates across a diverse and significant clade.

Investigating the path of plastid genome degradation in an early-transitional clade of heterotrophic orchids, and implications for heterotrophic angiosperms.

Parasitic organisms exemplify morphological and genomic reduction. Some heterotrophic, parasitic plants harbor drastically reduced and degraded plastid genomes resulting from relaxed selective pressure on photosynthetic function. However, few studies have addressed the initial stages of plastome degradation in groups containing both photosynthetic and nonphotosynthetic species. Corallorhiza is a genus of leafless, heterotrophic orchids that contains both green, photosynthetic species and nongreen, putatively nonphotosynthetic species, and represents an ideal system in which to assess the beginning of the transition to a "minimal plastome." Complete plastomes were generated for nine taxa of Corallorhiza using Illumina paired-end sequencing of genomic DNA to assess the degree of degradation among taxa, and for comparison with a general model of degradation among angiosperms. Quantification of total chlorophyll suggests that nongreen Corallorhiza still produce chlorophyll, but at 10-fold lower concentrations than green congeners. Complete plastomes and partial nuclear rDNA cistrons yielded a fully resolved tree for Corallorhiza, with at least two independent losses of photosynthesis, evidenced by gene deletions and pseudogenes in Co. striata and nongreen Co. maculata. All Corallorhiza show some evidence of degradation in genes of the NAD(P)H dehydrogenase complex. Among genes with open reading frames, photosynthesis-related genes displayed evidence of neutral evolution in nongreen Corallorhiza, whereas genes of the ATP synthase complex displayed some evidence of positive selection in these same groups, though for reasons unknown. Corallorhiza spans the early stages of a general model of plastome degradation and has added critical insight for understanding the process of plastome evolution in heterotrophic angiosperms.

An experimental model for the transplantation of fetal central nervous system cells to the injured spinal cord in rats

INTRODUCTION: Traumatic spinal cord injury is one of the most disabling conditions occurring in man and thus stimulates a strong interest in its histopathological, biochemical, and functional changes, primarily as we search for preventive and therapeutic methods. PURPOSE: To develop an experimental model for transplantation of cells from the fetal rat central nervous system to the site of an injured spinal cord of an adult rat in which the transplanted cells survive and become integrated. This experimental model will facilitate investigations of factors that promote regeneration and functional recovery after spinal cord trauma. MATERIAL AND METHODS: Fifteen adult Wistar rats underwent laminectomy, and an spinal cord lesion was made with microdissection. Fetal spinal cord tissue was then transplanted to the site of the injury. The rats were monitored over a 48-hour period, and then their vertebral column was completely removed for histological analysis. RESULTS: In 60 percent of transplanted rats, the fetal tissue at the injured site remained viable in the site of the lesion

An experimental model for the transplantation of fetal central nervous system cells to the injured spinal cord in rats.

INTRODUCTION: Traumatic spinal cord injury is one of the most disabling conditions occurring in man and thus stimulates a strong interest in its histopathological, biochemical, and functional changes, primarily as we search for preventive and therapeutic methods. PURPOSE: To develop an experimental model for transplantation of cells from the fetal rat central nervous system to the site of an injured spinal cord of an adult rat in which the transplanted cells survive and become integrated. This experimental model will facilitate investigations of factors that promote regeneration and functional recovery after spinal cord trauma. MATERIAL AND METHODS: Fifteen adult Wistar rats underwent laminectomy, and an spinal cord lesion was made with microdissection. Fetal spinal cord tissue was then transplanted to the site of the injury. The rats were monitored over a 48-hour period, and then their vertebral column was completely removed for histological analysis. RESULTS: In 60% of transplanted rats, the fetal tissue at the injured site remained viable in the site of the lesion.

Tromboembolismo pulmonar: estudo de sua incidencia e seus fatores de risco baseado em revisao de laudos de necropsias / Pulmonary thromboembolism: incidence study and risk factors based in necropsy award reviews

Dada a relevancia que o tromboembolismo pulmonar (TEP) vem adquirindo nos ultimos tempos, realizamos um estudo epidemiologico retrospectivo (caso-controle) embasado na analise de 1290 laudos de necropsias consecutivas realizadas em 1993 e 1994, no HCFMUSP, com posterior analise estatistica dos dados obtidos atraves dos programas Multlr e SPSS for Windows. Notamos que a incidencia de TEP foi de 12 por cento e que alguns fatores de risco como TVP (O.R.=13,98), trombose mural (O.R.=10,23), cirurgia ortopedica (O.R.=2,71), cirurgia neurologica (O.R.=4,16), doenca arterial obstrutiva periferica (O.R.=3,12) e ICC (O.R.=2,43) contribuem para o seu desenvolvimento. A insuficiencia hepatica apareceu como fator protetor (O.R.=0,77). Desta forma, achamos que a profilaxia nestes casos e necessaria para prevenir o TEP