The consequences of perinatal asphyxia (PA) include alterations which may manifest as schizophrenia. Characteristic features of this disease include a decrease in specific subpopulations of GABAergic ...cells and deterioration of social interaction. The purpose of this study is to assess if a deep and short‐hypothermic treatment can ameliorate this damage in a model of PA. Rats offsprings were exposed to 19 min of asphyxia by immersing the uterus horns in water at 37 °C followed by 30 min in air at 10 °C that resulted in 15 °C body temperature. At postnatal day 36–38, the rats were tested in the open field and social interaction paradigms and processed for immunostaining of calbindin and reelin. A brief exposure to deep hypothermia reversed the deterioration produced by PA in play soliciting. PA decreased the density of calbindin neurons in layer II of the Anterior Insular Cortex, while deep hypothermia reversed this effect. Paradoxically, in AIC, there was a significant increase in the number of reelin‐secreting neurons in layers II and III generated by PA and this increase was reversed by hypothermia. This suggests a compensatory mechanism, where reelin neurons trend to compensate for the loss of calbindin neurons, at least within Anterior Insular Cortex. Finally, the deep hypothermic shock might represent a valuable therapeutic alternative to treat PA.
At birth, there are calbindin+ cells in the cortex but no reelin+ cells besides cajal retzius neurons. Perinatal asphyxia (PA) seems to decrease the density of calbindin+ neurons while therapeutic hypothermia (Hyp) prevents this damage. GABAergic‐reelin+ neurons that appear in the cortex after birth seem to compensate the loss of calbindin+ neurons in the AIC.
Obstetrical complications of perinatal asphyxia (PA) can often induce lesions that, in the long-term, manifest as schizophrenia. A deterioration of the medial prefrontal cortex (mPFC) and a reduction ...in the number of GABAergic neurons are commonly observed in the pathophysiology of schizophrenia. In this study, we investigated the link between PA, reelin and calbindin diminution and psychiatric diseases that involve social interaction deficits. This was achieved by observing the effect of 19 min of asphyxia on both subpopulations of GABAergic neurons. PA was produced by water immersion of fetus-containing uterus horns removed by cesarean section from ready-to-deliver rats. PA generated a significant and specific decrease in the number of reelin-secreting neurons in mPFC layer VI F(2, 6) = 8.716, p = 0.016; PA vs. vaginal controls (VC), p = 0.03, and PA vs. cesarean controls (CC), p = 0.022. This reduction reached approximately 60% on average. Changes in the percentage of reelin neurons including all the cortex layers did not achieve a significant outcome but a trend: CC % 10.61 ± 1.34; PA % 8.64 ± 1.71 F(2, 6) = 1.299, p = 0.33. In the case of calbindin, there was a significant decrease in cell density in the PA group 2-way repeated-measures ANOVA, F(1, 4) = 13.03, p = 0.0226. The multiple-comparisons test showed significant differences in the superficial aspect of layer II (Sidak test for multiple comparisons CC vs. PA at 200 µm: p = 0.003). A small, but significant difference could be seen when the distance from the pia mater to the start of layer VI was analyzed (CC mean ± SEM = 768.9 ± 8.382; PA mean ± SEM = 669.3 ± 17.75; p = 0.036). Rats exposed to PA showed deterioration in social interactions, which manifested as a decrease in play soliciting. In this model, which involved severe/moderate asphyxia, we did not find significant changes in locomotive activity or anxiety indicators in the open field task. The loss of reelin neurons could be conducive to the shrinkage of the prelimbic cortex through the reduction in neuropil and the deterioration of the function of this structure.
Purpose To compare the perception of the quality of life (QOL) of community-dwelling older adults with the phenotype of frailty. Methods Cross-sectional analysis of baseline data of the "Cohort of ...Obesity, Sarcopenia and Frailty of Mexican Older Adults" (COSFOMA). Operationalization of frailty was carried out using the phenotype as follows: weight loss, self-report of exhaustion, low physical activity, slow gait, and weakness. QOL was measured using two scales: World Health Organization Quality of Life of Older Adults (WHOQOL-OLD), which is a specific instrument for the elderly population, and Short Form-36 Health Survey (SF-36), a generic instrument to evaluate the QOL related to health. One-way analyses of variance were conducted to assess the differences among the three phenotypes of frailty and QOL perception. Results There were 1252 older adult participants who were analyzed; 11.2% (n = 140) had frailty, 50.3% (n = 630) pre-frailty and 38.5% (n = 482) were not frail. The mean (±SD) total score of the WHOQOL-OLD according to the phenotype of frailty was 60.3 (13.9) for those with frailty, 67.4 (12.7) pre-frailty and 72.4 (11.2) not frail (ANOVA, p < 0.001). The mean (±SD) of the SF-36 of the physical and mental component measures the sum, 38.9 (9.9) and 41.9 (11.3) with frailty, 45.7 (9.1) and 46.6 (9.8) prefrailty, and 49.6 (7.3) and 49.4 (7.9) not frail, respectively (ANOVA, p < 0.001). Conclusions Frailty is observed in 1/10 community-dwelling older adults. Those with frailty and pre-frailty had a lower perception of QOL compared with those who were not frail.
Screening of industrial enzymes for deproteinization of shrimp head for chitin recovery Valdez-Pena, Angel U., Coyotefoods Biopolymer and Biotechnology Co., Coahuila State, Mexico; Espinoza-Perez, Judith D., Coyotefoods Biopolymer and Biotechnology Co., Coahuila State, Mexico; Sandoval-Fabian, Georgina C., Centro de Investigacion y Asistencia en Tecnologia Diseno del Estado de Jalisco A.C., Jalisco State, Mexico ...
Food science and biotechnology,
04/2010, Letnik:
19, Številka:
2
Journal Article
Recenzirano
Food grade proteolytic enzymes were examined for deproteinization of shrimp head. Shrimp head was easily deproteinized by Alcalase∨_ and trypsin at a pH of 8.0. Alcalase was chosen as the most ...efficient commercial enzyme for deproteinization of shrimp head. Alcalase treatment of shrimp head recorded 61% of weight loss on dry basis and a residual protein of 275 mg/g dried shrimp head. The enzymatically deproteinized shrimp head was later demineralized with lactic acid using microwave radiation at 400W. The combination of enzymatic and physicochemical treatments promoted the chitin recovery from dried shrimp head under eco-friendly conditions.
La generación e implementación de estrategias para disminuir la transmisión de SARS-CoV-2 son un reto imperante para el país. Las estrategias deben ser dinámicas y específicas para cada región ...buscando equilibrar el impacto en la salud y en la economía. Esta tarea debe abordarse desde un enfoque interdisciplinario con el fin de estudiar la problemática de manera holística. En el presente artículo se presentan algunos hallazgos y revisiones realizadas en el marco del proyecto SISCOVID, en el cual se utilizan modelos sistémicos de simulación computacional para apoyar la toma de decisiones para el control y mitigación de la pandemia en Colombia. El proyecto está conformado por investigadores de la Universidad de Los Andes, el Centro Nacional de Consultoría (CNC) y la Universidad de Ibagué, en alianza con universidades internacionales y empresas. El proyecto ha logrado apoyar a los tomadores de decisiones en formular estrategias para disminuir la transmisión de SARS-CoV-2 en contextos urbanos en las ciudades de Barranquilla, Bogotá, Cali, Cartagena y Medellín. Palabras clave: SARS-CoV-2, Epidemiología, Prevención, Modelos sistémicos, Sistemas Complejos The development and implementation of strategies to reduce SARS-CoV2 transmission is a prevailing challenge for Colombia. These strategies ought to be dynamic and specific to each region, seeking to balance health and economic impacts. This task calls for an interdisciplinary approach to ensure a holistic view of the problem. This article presents findings and results obtained from the SISCOVID project, which used simulated systemic models to support decision making and efforts to mitigate the pandemic in Colombia. The project included researchers from Universidad de Los Andes, the Centro Nacional de Consultoría (CNC) and Universidad de Ibagué, in alliance with several international universities and companies. SISCOVID helped decision makers design strategies to reduce SARS-CoV-2 transmission in urban contexts for the cities of Barranquilla, Bogotá, Cali, Cartagena, and Medellín. Key words: SARS-CoV-2, Epidemiology, Prevention, Systemic Models, Complex Systems
The need for the conformal deposition of TiO2 thin films in device fabrication has motivated a search for thermally robust titania precursors with noncorrosive byproducts. Alkylamido-cyclopentadienyl ...precursors are attractive because they are readily oxidized, yet stable, and afford environmentally mild byproducts. We have explored the deposition of TiO2 films on OH-terminated SiO2 surfaces by in situ Fourier transform infrared spectroscopy using a novel titanium precursor (EtCp)Ti(NMe2)3 (1), Et = CH2CH3 with either ozone or water. This precursor initially reacts with surface hydroxyl groups at ≥150 °C through the loss of its NMe2 groups. However, once the precursor is chemisorbed, its subsequent reactivities toward ozone and water are very different. There is a clear reaction with ozone, characterized by the formation of monodentate formate and/or chelate bidentate carbonate surface species; in contrast, there is no detectable reaction with water. For the ozone-based ALD process, the surface formate/carbonate species react with the NMe2 groups during the subsequent pulse of 1, forming TiOTi bonds. Ligand exchange is observed within the 250–300 °C ALD window. X-ray photoelectron spectroscopy confirms the deposition of stoichiometric TiO2 films with no detectable impurities. For the water-based process, ligand exchange is not observed. Once 1 is adsorbed, there is no spectroscopic evidence for further reaction. However, there is still TiO2 deposition under typical ALD conditions. Co-adsorption experiments with controlled vapor pressures of water and 1 indicate that deposition arises solely from 1/water gas-phase reactions. This striking lack of reactivity between chemisorbed 1 and water is attributed to the electronic and steric effects of the EtCp group and facilitates the observation of gas-phase reactions.
Despite the success of plasma-enhanced atomic layer deposition (PEALD) in depositing quality silicon nitride films, a fundamental understanding of the growth mechanism has been difficult to obtain ...because of lack of in situ characterization to probe the surface reactions noninvasively and the complexity of reactions induced/enhanced by the plasma. These challenges have hindered the direct observation of intermediate species formed during the reactions. We address this challenge by examining the interaction of Ar plasma using atomically flat, monohydride-terminated Si(111) as a well-defined model surface and focusing on the initial PEALD with aminosilanes. In situ infrared and X-ray photoelectron spectroscopy reveals that an Ar plasma induces desorption of H atoms from H–Si(111) surfaces, leaving Si dangling bonds, and that the reaction of di-sec-butylaminosilane (DSBAS) with Ar plasma-treated surfaces requires the presence of both active sites (Si dangling bonds) and Si–H; there is no reaction on fully H-terminated or activated surfaces. By contrast, high-quality hydrofluoric acid-etched Si3N4 surfaces readily react with DSBAS, resulting in the formation of O–SiH3. However, the presence of back-bonded oxygen in O–SiH3 inhibits H desorption by Ar or N2 plasma, presumably because of stabilization of H against ion-induced desorption. Consequently, there is no reaction of adsorbed aminosilanes even after extensive Ar or N2 plasma treatments; a thermal process is necessary to partially remove H, thereby promoting the formation of active sites. These observations are consistent with a mechanism requiring the presence of both undercoordinated nitrogen and/or dangling bonds and unreacted surface hydrogen. Because active sites are involved, the PEALD process is found to be sensitive to the duration of the plasma exposure treatment and the purge time, during which passivation of these sites can occur.
Alzheimer's disease (AD) is characterized by cognitive impairment and the presence of neurofibrillary tangles and senile plaques in the brain. Neurofibrillary tangles are composed of ...hyperphosphorylated tau, while senile plaques are formed by amyloid-β (Aβ) peptide. The amyloid hypothesis proposes that Aβ accumulation is primarily responsible for the neurotoxicity in AD. Multiple Aβ-mediated toxicity mechanisms have been proposed including mitochondrial dysfunction. However, it is unclear if it precedes Aβ accumulation or if is a consequence of it. Aβ promotes mitochondrial failure. However, amyloid β precursor protein (AβPP) could be cleaved in the mitochondria producing Aβ peptide. Mitochondrial-produced Aβ could interact with newly formed ones or with Aβ that enter the mitochondria, which may induce its oligomerization and contribute to further mitochondrial alterations, resulting in a vicious cycle. Another explanation for AD is the tau hypothesis, in which modified tau trigger toxic effects in neurons. Tau induces mitochondrial dysfunction by indirect and apparently by direct mechanisms. In neurons mitochondria are classified as non-synaptic or synaptic according to their localization, where synaptic mitochondrial function is fundamental supporting neurotransmission and hippocampal memory formation. Here, we focus on synaptic mitochondria as a primary target for Aβ toxicity and/or formation, generating toxicity at the synapse and contributing to synaptic and memory impairment in AD. We also hypothesize that phospho-tau accumulates in mitochondria and triggers dysfunction. Finally, we discuss that synaptic mitochondrial dysfunction occur in aging and correlates with age-related memory loss. Therefore, synaptic mitochondrial dysfunction could be a predisposing factor for AD or an early marker of its onset.
Food grade proteolytic enzymes were examined for deproteinization of shrimp head. Shrimp head was easily deproteinized by $Alcalase^{(R)}$ and trypsin at a pH of 8.0. Alcalase was chosen as the most ...efficient commercial enzyme for deproteinization of shrimp head. Alcalase treatment of shrimp head recorded 61% of weight loss on dry basis and a residual protein of 275 mg/g dried shrimp head. The enzymatically deproteinized shrimp head was later demineralized with lactic acid using microwave radiation at 400 W. The combination of enzymatic and physicochemical treatments promoted the chitin recovery from dried shrimp head under eco-friendly conditions.
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