Las imágenes sobre enlace químico usadas en los libros de texto de educación secundaria : análisis desde los resultados de la investigación educativa

En este artículo se analizan las imágenes o ilustraciones contenidas en libros de texto en relación con el enlace químico. El objetivo ha sido desvelar si estas imágenes se adecuan a los fundamentos teóricos hallados en la bibliografía sobre el tema. Se han analizado 12 libros de texto pertenecientes a los niveles argentinos de EGB 3 (12-14 años) y Polimodal (15-17 años). Esto ha supuesto un total de 16 imágenes de EGB 3 y de 62 imágenes de Polimodal. Los resultados, a pesar de ser muy heterogéneos, muestran una relación escasa texto-imagen, y un predominio del tipo de texto expositivo. Además, en EGB 3, el 70%[ de las imágenes son modelos de bajo nivel (sin configuración electrónica), frente al 30% que son de alto nivel, mientras que en Polimodal ocurre prácticamente lo contrario.In this article, the images or illustrations contained in textbooks related to chemical bonds are analyzed. The objective was to reveal whether or not these images are adapted to the previous theoretic outcomes. 12 Argentina junior high school (12-14 years old) and senior high school (15-17 years old) textbooks were analyzed. A total of 16 junior high school images and 62 senior high school images were studied. Despite the fact that they are very heterogeneous, the results show a very scarce text-image relationship, and a prevalence for expositive types of text. In addition, in junior high school, 70% of the images are low level models (without electronical configuration), as opposed to the 30% that are high level whereas in senior high school, practically the opposite occurs

High-yield production of short GpppA- and (7Me)GpppA-capped RNAs and HPLC-monitoring of methyltransfer reactions at the guanine-N7 and adenosine-2′O positions

Many eukaryotic and viral mRNAs, in which the first transcribed nucleotide is an adenosine, are decorated with a cap-1 structure, (7Me)G(5′)-ppp(5′)-A(2′OMe). The positive-sense RNA genomes of flaviviruses (Dengue, West Nile virus) for example show strict conservation of the adenosine. We set out to produce GpppA- and (7Me)GpppA-capped RNA oligonucleotides for non-radioactive mRNA cap methyltransferase assays and, in perspective, for studies of enzyme specificity in relation to substrate length as well as for co-crystallization studies. This study reports the use of a bacteriophage T7 DNA primase fragment to synthesize GpppAC(n) and (7Me)GpppAC(n) (1 ≤ n ≤ 9) in a one-step enzymatic reaction, followed by direct on-line cleaning HPLC purification. Optimization studies show that yields could be modulated by DNA template, enzyme and substrate concentration adjustments and longer reaction times. Large-scale synthesis rendered pure (in average 99%) products (1 ≤ n ≤ 7) in quantities of up to 100 nmol starting from 200 nmol cap analog. The capped RNA oligonucleotides were efficient substrates of Dengue virus (nucleoside-2′-O-)-methyltransferase, and human (guanine-N7)-methyltransferase. Methyltransfer reactions were monitored by a non-radioactive, quantitative HPLC assay. Additionally, the produced capped RNAs may serve in biochemical, inhibition and structural studies involving a variety of eukaryotic and viral methyltransferases and guanylyltransferases

Dysphagia in multiple system atrophy consensus statement on diagnosis, prognosis and treatment.

Multiple system atrophy (MSA) is a neurodegenerative disorder characterized by a combination of autonomic failure plus cerebellar syndrome and/or parkinsonism. Dysphagia is a frequent and disabling symptom in MSA and its occurrence within 5 years of motor onset is an additional diagnostic feature. Dysphagia can lead to aspiration pneumonia, a recognized cause of death in MSA. Guidelines for diagnosis and management of dysphagia in MSA are lacking. An International Consensus Conference among experts with methodological support was convened in Bologna to reach consensus statements for the diagnosis, prognosis, and treatment of dysphagia in MSA. Abnormalities of the oral and pharyngeal phases of swallowing, esophageal dysfunction and aspiration occur in MSA and worsen as the disease progresses. According to the consensus, dysphagia should be investigated through available screening questionnaires and clinical and instrumental assessment (videofluoroscopic study or fiberoptic endoscopic evaluation of swallowing and manometry) at the time of MSA diagnosis and periodically thereafter. There is evidence that dysphagia is associated with poor survival in MSA, however effective treatments for dysphagia are lacking. Compensatory strategies like diet modification, swallowing maneuvers and head postures should be applied and botulinum toxin injection may be effective in specific conditions. Percutaneous endoscopic gastrostomy may be performed when there is a severe risk of malnutrition and pulmonary complications, but its impact on survival is undetermined. Several research gaps and unmet needs for research involving diagnosis, prognosis, and treatment were identified

Dysphagia in multiple system atrophy consensus statement on diagnosis, prognosis and treatment

Multiple system atrophy (MSA) is a neurodegenerative disorder characterized by a combination of autonomic failure plus cerebellar syndrome and/or parkinsonism. Dysphagia is a frequent and disabling symptom in MSA and its occurrence within 5 years of motor onset is an additional diagnostic feature. Dysphagia can lead to aspiration pneumonia, a recognized cause of death in MSA. Guidelines for diagnosis and management of dysphagia in MSA are lacking. An International Consensus Conference among experts with methodological support was convened in Bologna to reach consensus statements for the diagnosis, prognosis, and treatment of dysphagia in MSA. Abnormalities of the oral and pharyngeal phases of swallowing, esophageal dysfunction and aspiration occur in MSA and worsen as the disease progresses. According to the consensus, dysphagia should be investigated through available screening questionnaires and clinical and instrumental assessment (videofluoroscopic study or fiberoptic endoscopic evaluation of swallowing and manometry) at the time of MSA diagnosis and periodically thereafter. There is evidence that dysphagia is associated with poor survival in MSA, however effective treatments for dysphagia are lacking. Compensatory strategies like diet modification, swallowing maneuvers and head postures should be applied and botulinum toxin injection may be effective in specific conditions. Percutaneous endoscopic gastrostomy may be performed when there is a severe risk of malnutrition and pulmonary complications, but its impact on survival is undetermined. Several research gaps and unmet needs for research involving diagnosis, prognosis, and treatment were identified

A multinational consensus on dysphagia in Parkinson's disease: screening, diagnosis and prognostic value

Background: Parkinson’s disease (PD) is a neurodegenerative disorder characterized by a combination of motor and non-motor dysfunction. Dysphagia is a common symptom in PD, though it is still too frequently underdiagnosed. Consensus is lacking on screening, diagnosis, and prognosis of dysphagia in PD. Objective: To systematically review the literature and to define consensus statements on the screening and the diagnosis of dysphagia in PD, as well as on the impact of dysphagia on the prognosis and quality of life (QoL) of PD patients. Methods: A multinational group of experts in the field of neurogenic dysphagia and/or PD conducted a systematic revision of the literature published since January 1990 to February 2021 and reported the results according to PRISMA guidelines. The output of the research was then analyzed and discussed in a consensus conference convened in Pavia, Italy, where the consensus statements were drafted. The final version of statements was subsequently achieved by e-mail consensus. Results: Eighty-five papers were used to inform the Panel’s statements even though most of them were of Class IV quality. The statements tackled four main areas: (1) screening of dysphagia: timing and tools; (2) diagnosis of dysphagia: clinical and instrumental detection, severity assessment; (3) dysphagia and QoL: impact and assessment; (4) prognostic value of dysphagia; impact on the outcome and role of associated conditions. Conclusions: The statements elaborated by the Consensus Panel provide a framework to guide the neurologist in the timely detection and accurate diagnosis of dysphagia in PD

Consensus on the treatment of dysphagia in Parkinson's disease

BACKGROUND: Dysphagia is common in Parkinson's disease (PD). The effects of antiparkinsonian drugs on dysphagia are controversial. Several treatments for dysphagia are available but there is no consensus on their efficacy in PD. OBJECTIVE: To conduct a systematic review of the literature and to define consensus statements on the treatment of dysphagia in PD and related nutritional management. METHODS: A multinational group of experts in the field of neurogenic dysphagia and/or Parkinson's disease conducted a systematic evaluation of the literature and reported the results according to PRISMA guidelines. The evidence from the retrieved studies was analyzed and discussed in a consensus conference organized in Pavia, Italy, and the consensus statements were drafted. The final version of statements was subsequently achieved by e-mail consensus. RESULTS: The literature review retrieved 64 papers on treatment and nutrition of patients with PD and dysphagia, mainly of Class IV quality. Based on the literature and expert opinion in cases where the evidence was limited or lacking, 26 statements were developed. CONCLUSIONS: The statements developed by the Consensus panel provide a guidance for a multi-disciplinary treatment of dysphagia in patients with PD, involving neurologists, otorhinolaryngologists, gastroenterologists, phoniatricians, speech-language pathologists, dieticians, and clinical nutritionists

Ceruloplasmin Protects Against Rotenone-Induced Oxidative Stress and Neurotoxicity

To clarify the neuroprotective property of ceruloplasmin and the pathogenesis of aceruloplasminemia, we generated ceruloplasmin-deficient (CP−/−) mice on the C57BL/10 genetic background and further treated them with a mitochondrial complex I inhibitor, rotenone. There was no iron accumulation in the brains of CP−/− mice at least up to 60 weeks of age. Without rotenone treatment, CP−/− mice showed slight motor dysfunction compared with CP+/+ mice, but there were no detectable differences in the levels of oxidative stress markers between these two groups. A low dose of rotenone did not affect the mitochondrial complex I activity in our mice, however, it caused a significant change in motor behavior, neuropathology, or the levels of oxidative stress markers in CP−/− mice, but not in CP+/+ mice. Our data support that ceruloplasmin protects against rotenone-induced oxidative stress and neurotoxicity, probably through its antioxidant properties independently of its function of iron metabolism

The Central Clock Neurons Regulate Lipid Storage in Drosophila

A proper balance of lipid breakdown and synthesis is essential for achieving energy homeostasis as alterations in either of these processes can lead to pathological states such as obesity. The regulation of lipid metabolism is quite complex with multiple signals integrated to control overall triglyceride levels in metabolic tissues. Based upon studies demonstrating effects of the circadian clock on metabolism, we sought to determine if the central clock cells in the Drosophila brain contribute to lipid levels in the fat body, the main nutrient storage organ of the fly. Here, we show that altering the function of the Drosophila central clock neurons leads to an increase in fat body triglycerides. We also show that although triglyceride levels are not affected by age, they are increased by expression of the amyloid-beta protein in central clock neurons. The effect on lipid storage seems to be independent of circadian clock output as changes in triglycerides are not always observed in genetic manipulations that result in altered locomotor rhythms. These data demonstrate that the activity of the central clock neurons is necessary for proper lipid storage

Scoliosis in patients with Prader Willi Syndrome – comparisons of conservative and surgical treatment

In children with Prader Willi syndrome (PWS), besides growth hormone (GH) therapy, control of the food environment and regular exercise, surgical treatment of scoliosis deformities seems the treatment of choice, even though the risks of spinal surgery in this specific population is very high. Therefore the question arises as to whether the risks of spinal surgery outweigh the benefits in a condition, which bears significant risks per se. The purpose of this systematic review of the Pub Med literature was to find mid or long-term results of spinal fusion surgery in patients with PWS, and to present the conservative treatment in a case study of nine patients with this condition