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An accurate estimation of photovoltaic (PV) power production is crucial for organizing and regulating solar PV power plants. The suitable prediction is often affected by the variable nature of solar resources, system location and some internal/external disturbances, such as system effectiveness, climatic factors, etc. This paper develops a novel strategy for applying a predictive control technique to PV power forecasting applications in a smart grid environment. The strategy develops the model predictive control (MPC) under demand response (DR) and some data-driven methods. It has been found that it is challenging to model an MPC for solar power forecasting regardless of its robustness and ability to handle constraints and disturbance. Thus, an optimal quadratic performance index-based MPC scheme is formulated to model a forecasting method for a PV power prediction. This strategy is then compared with some machine learning approaches. The developed strategies solve the problem of accurately estimating the direct current (DC) power yielded from the PV plant in a real-world implementation. The study also considers external disturbances to evaluate the significance of the developed methods for a suitable forecast. Therefore, this study optimally demonstrates that an accurate solar PV DC power prediction can relatively be estimated with an appropriate strategy, such as MPC and MLs, considering the system disturbances. This study also offers promising results for intelligent and real-time energy resource estimation that assist in developing the solar power sector.

Photovoltaic (PV) systems are popular for their reliability and zero fuel costs. However, only around 20 % of solar energy is converted into electricity, while the remainder is dissipated as waste heat. Excessive waste heat affects the lifespan of PV systems, leading to abnormal operating temperatures. In this notion, Photovoltaic-thermal (PV/T) systems are introduced to extract waste heat through various cooling techniques to harness electrical and thermal energies, demonstrating their capabilities through experimental and modeling techniques. Researchers have sought to develop optimized modeling techniques based on empirical, semi-empirical, and AI-based modeling for efficient execution of PV/T systems. This study reviews the current optimization developments in the PV/T systems, focusing on multiple numerical and experimental designs. Various cooling methods, including air, water, and phase change materials (PCM) with nanofluids, are examined for their promising contributions to electrical and thermal efficiency enhancement. Additionally, optimization methods have been investigated by incorporating automated processes into PV/T systems employing self-automation techniques. These processes aim to reduce the overall cost and establish a self-sustaining performance. Finally, the challenges and recommendations for future research for PV/T enhancement are highlighted.

The objective was to characterize a herd of 73 Nellore heifers, identifying resistant, resilient, and susceptible animals to gastrointestinal helminths, relating the global methylation of the DNA of these animals with the degree of helminthiasis and factors that interfere with performance. Individual count of eggs per gram of feces (EPG), fecal culture for gender identification, weighing and blood sampling were carried out to determine PCV, STP, EOS, IgG, followed by DNA extraction and methylation analysis. The results were: 47% resistant animals, 34% resilient, and 19% susceptible to gastrointestinal helminth infections, with EPG counts of 53, 216, and 841, respectively, showing a statistical difference between all groups. The quantification of DNA methylation was 0.311, 0.245 and 0.178, respectively, for resistant, resilient, and susceptible animals, with a correlation being found between resistance to gastrointestinal helminths and overall DNA methylation. For weight gain, resistant and resilient animals showed higher values than susceptible ones, with a correlation between weight gain and EPG. The same was observed for VG; however, there was no statistical difference to the EOS, PPT, and IgG values. A significant correlation was found between PCV and EPG; quantifications of PCV and methylated DNA, STP and EPG; VG and STP. Therefore, the methodologies used made it possible to identify the animals regarding the degree of infection by gastrointestinal nematodes, making it possible to correlate the resistance of cattle to helminths with the amount of global DNA methylation and its performance.

Introduction Cochlear implantation has been considered as the best treatment in patients with severe to profound hearing loss unaidable with hearing aids. The main value of endoscope-assisted cochlear implantation is improved visibility of the RW

Abstract Background Mucormycosis is a serious life-threatening fungal infection that recently made severe sudden and devastating surge during the second wave of the COVID-19 epidemic with a mortality rate of up to 50%. Although the causality link between COVID-19 and rhino-orbito-cerebral mucormycosis (ROCM) remains unclear, many factors including poor diabetes control, high doses of steroids, viral-induced lymphopenia, and cytokine storm have been attributed to ROCM in patients with COVID-19. Orienting to risk factors and early recognition of this potentially fatal opportunistic infection is the key to optimal management and improved outcomes. In these contexts, we conducted a prospective study for 33 patients admitted to our tertiary hospital to determine the risk factors for ROCM in patients with COVID-19 and the cumulative mortality rates. Results This study found a statistically significant relation between the fate of death in COVID-MUCOR patients who had presented fever, ophthalmoplegia, facial skin necrosis, and visual loss with those who received dose of steroid to control their respiratory symptoms P < 0.001. Death from COVID-MUCOR was statistically significant related to the prolonged interval from the onset of the symptoms to start of treatment and intervention. Also, it was found that there was a significant decrease in duration between COVID-19 infection and the start of mucormycosis (days) with incidence of DKA on admission. Nineteen (57.6%) of the patients had uncontrolled diabetes mellitus (hemoglobin A1C (HbA1c) of > 7.0%). Conclusion Mucormycosis epidemic was precipitated by a unique confluence of risk factors: diabetes mellitus, widespread use of steroids, and perhaps SARS-CoV-2 infection itself. Restricting steroid use in patients with severe COVID-19 requiring oxygen therapy, and screening for and optimally controlling hyperglycemia, can prevent COVID-MUCOR in a large majority.

Abstract Background The introduction of sialendoscopy has been a major step forward in providing an accurate means of diagnosing and locating submandibular sialolithiasis, also in permitting minimally invasive surgical treatment that can successfully manage those stones aiming for gland preservation. Methods We conducted a systemic review to assess the efficacy and safety of combined sialendoscopic assisted surgery in the management of submandibular sialolithiasis. This study included published medical articles from 2000 till 2022 concerning the efficacy and safety of combined sialendoscopic-assisted surgery in management of submandibular sialolithiasis searching Medline database (PubMed), Web of Science, Springer, Cochrane library, EMBASE. Fifteen articles met the inclusion criteria and were reviewed and analyzed. Results The success rate of combined sialendoscopic assisted surgery in management of submandibular sialolithiasis is 0.955% with 95% CI: (91.4% to 98.5). The overall percentage of sialadenectomy cases in the included studies is 2%. The overall percentage of complications in the included studies is 8%. Conclusion Combined sialendoscopic-assisted surgery is efficient and safe in management of submandibular sialolithiasis.

Solar PV technology’s growth is fast and widespread in the United Arab Emirates (UAE), even though UAE has harsh climate conditions, ambient temperature, irradiance, and humidity are very high during most of the year. These conditions affect the performance and lifespan of the PV systems installed in the UAE. The current work aims to comprehensively assess the performance of a PV system installed in Sharjah city in UAE in different year seasons. A complete experimental setup for a 2.88 kW PV grid-connected system under the terrestrial conditions of Sharjah city is established. Exergy analysis procedure are performed based on the second law of thermodynamics which presents a different and informative means of evaluating and comparing PV systems reasonably and implicitly. Exergy analysis yields efficiencies that show how nearly actual performance methods recognize more clearly than energy analysis the causes and locations of thermodynamic losses. The results show that January has the highest efficiency while July has the lowest efficiency due to the highest ambient temperature in July. Furthermore, the lowest PV module temperature and highest electrical efficiency obtain at low and high ambient temperatures and highest wind speed. At the same time, the highest electrical power exists at low ambient temperature and the high irradiance value. The highest average PV exergy of 15.34% and lowest average PV exergy of 11.80% were detected in January and July, respectively. The low ambient temperatures in January courses reduced low thermal losses and kept the PV model temperature. However, the low solar radiation limited the conversion yield of the PV system.

Researchers are becoming more interested in renewable energies as a viable answer for today’s energy needs due to the rising demand for energy and climate changes brought on by the use of fossil fuel resources. One of the most significant sources of renewable energy is solar energy. Photovoltaic systems are used to convert the received solar radiation to electricity. Low overall performance throughout the operational time caused by raising the solar cells’ temperature is one of the most significant problems with the use of photovoltaic systems. In this experimental work, the influence of optical filters on the performance of photovoltaic panels was studied under Sharjah meteorological conditions. In this study, a 50 W solar PV module’s outdoor performance characteristics were analyzed. This case study employed a Plexiglas sheet, a box filled with air and water, and affixed it directly to the top surface of the PV panel to demonstrate the impact of the Plexiglas as an optical filter on the electrical productivity of the PV panel in relation to the variation in temperature caused by the filters. By imposing optical filters, and therefore lowering the temperature of the system, this work shows promising results in boosting the performance of the PV module. Module current drops dramatically as solar irradiance is blocked, yet panel voltage rises for filter-covered panels compared to the reference panel. In terms of fill factor and electrical efficiency, there has been a noticeable improvement. The voltage at maximum power, electrical efficiency, and maximum output power increased significantly. The average efficiencies of a reference PV module, a plexiglass-sheet-covered PV module, and a plexiglass-air-box-covered PV module are 7.02%, 7.5%, and 8.12%, respectively. In comparison to the reference module’s average efficiency of 6.66%, the covered PV module with plexiglass water box averages 6.74%

Solar PV technology is rapidly and widely expanding throughout the world, particularly in the United Arab Emirates (UAE). The UAE has harsh climate conditions, with high ambient temperature, irradiance, and humidity for most of the year. In this study, three-dimensional numerical simulations were run for a 2.88 kW PV grid-connected system in Sharjah, UAE, under actual conditions. The experimental and mathematical results for PV module temperature and electrical power are compared. The parametric study looks at how weather conditions affect system temperature, electrical efficiency, and power. Furthermore, the current research determined the cooling requirements for such PV systems in a variety of terrestrial conditions. To determine how ambient temperature and wind speed affect PV module temperature, electrical efficiency, and electrical output under various irradiance levels, a parametric study was conducted. The findings demonstrate that at low irradiance, low and high ambient temperatures and wind speeds, respectively, yield the lowest PV module temperature and maximum electrical efficiency. High irradiance values have no effect on wind speed, but low ambient temperatures have the most electrical power. Back cooling must be at least 200 W/m2 K to maintain an electrical efficiency of roughly 14.75%. The reduction of the highest temperature at the center of the cell of the 2.88 kW PV grid-connected system by using back cooling reduces by 26 °C for the worse case season where the highest temperature occurs.

Recently, the Modular Multilevel Converter (MMC) has drawn significant attention due to its diverse merits and its applicability to a wide range of medium to high-power applications. The growing interest in the MMC can be attributed to its attractive features such as modularity, reliability, and high voltage capability. Significant research has been conducted on the MMC over the last few years to develop its operation and control in various applications. However, the application of MMCs in microgrids remains a largely unexplored topic. Therefore, this paper aims to address this research gap by offering an in-depth review of the latest developments concerning circuit topologies, control schemes, and fault-tolerance strategies of MMC within microgrid applications. This comprehensive review not only provides a synthesized overview of the current state of the art but also paves the way for future investigations in this promising field. The outcomes from this study are expected to stimulate further advancements in MMC applications in microgrid systems, thus contributing to the continuous improvement and evolution of microgrids.

The prevalence of helminths in horses may vary, depending on climatic factors and host susceptibility. The objective of this study was to evaluate the seasonal dynamics of helminth infection in grazing horses, from October 2015 to September 2016. In total, 104 crossbred horses of different age groups, males and females in a single herd, participated in this study. Individual fecal samples were collected every 28 days for counting of eggs per gram of feces (EPG) and fecal cultures. The horses were evaluated individually for weight, body condition score (BCS) and clinical status. Climatic information relating to the farm was also collected. The categories most affected by helminths were foals and senior horses, with EPG averages of 1271.9 and 1186.5, respectively. The EPG averages for all animal categories together, in the four seasons were: 1042.1 spring; 1508.9 summer; 817.8 autumn; and 571.1 winter. Through the body condition evaluation, it was seen that senior animals presented the lowest BCS in all seasons. It was concluded that the season in which these animals were most affected by helminth infections was the summer and that the most susceptible categories were foals and senior horses.

Abstract Background The prevalence of olfactory/gustatory dysfunctions among hospitalized SARS-CoV-2-infected patients is highly variable between different studies, ranging from 5.6% in the Asian population to 86% in the European population. The study aimed to detect the prevalence and the recovery of olfactory/gustatory dysfunctions in hospitalized SARS-CoV-2-infected patients in an Egyptian tertiary care center. A total of 579 hospitalized patients were enrolled. Demographic data as well as upper respiratory tract symptoms including olfactory/gustatory dysfunctions and other risk factors were documented. Then the recovery of olfactory/gustatory dysfunctions after 6 months was followed up. Results 50.6% had olfactory/gustatory dysfunctions (24.2% had a total smell and taste loss). A logistic regression analysis revealed a statistical significance between olfactory/gustatory dysfunctions and female gender and presence. Most patients (88.4%) reported partial or complete recovery during the 6 months (28.0% and 60.4%, respectively), while 11.6% of patients did not recover. The median time to start recovery was 3 days, and the median time to the best recovery was 22 days. Conclusions Olfactory/gustatory dysfunctions should be recognized for early detection of COVID-19 infection. Most recovery of olfactory/gustatory dysfunction in COVID-19 infection starts within 3 days and reaches the best recovery within 19 to 24 days. Female gender and the presence of general symptoms are associated with olfactory/gustatory dysfunctions in the hospitalized COVID-19 patients.

Abstract Background Breast cancer is one of the most common types of cancer. Ribonucleotide reductase (RNR) is a heterodimeric tetramer consisting of two Ribonucleoside-diphosphate reductase large subunits (RRM1) and two Ribonucleoside-diphosphate reductase small subunits (RRM2). RRM2 is the building subunit of RNR that is important for synthesis of Deoxynucleoside triphosphate (dNTP) during S phase of cell cycle during DNA replication. RRM2 is associated with poor prognosis in lung and colorectal cancer. In breast cancer, increased RRM2 protein level is strongly correlated with large tumour size, positive lymph node and relapse. In this study, we aimed to study expression of RRM2 in breast cancer and to correlate it with different clinicopathological parameters in Egyptian women. Material and methods This study was performed by investigating RRM2 protein expression in breast cancer and correlating the results with other clinicopathological variables using immunohistochemistry and tissue microarrays. Results About 77% of cases were RRM2 positive. High Ki67 was observed in cases with high RRM2 score. The majority of non-luminal cases expressed RRM2, however this was statistically insignificant. In ER positive group, RRM2 expression was associated with shorter disease free survival with borderline significance. Conclusion RRM2 protein expression can help in evaluating outcome of breast cancer patients and could be a potential therapeutic target.

Introduction Our primary aim was to document our interactions with patients subjected to mechanical ventilation (MV) in the Critical Care Department focusing on epidemiological characteristics; the initial modes of ventilation used, and initial settings. Our secondary aim was to document final clinical outcomes of MV, including length of stay, weaning, complications, and hospital mortality. Patients and methods Patients’ data were collected retrospectively from January 2010 to December 2014 (5 years) through reviewing an electronic database (Medica Plus). Results We enrolled a total of 1081 patients. The duration of ventilation was 6±10 days, and length of ICU stay was 13±15 days. The predominant indications of ventilation were cardiac diseases followed by respiratory diseases, neurological diseases, sepsis, and septic shock. Volume controlled ventilation was the most common initial mode of ventilation followed by Non Invasive Continuous Positive Airway Pressure – Pressure Support (NICPAP-PS) and pressure controlled ventilation. Noninvasive ventilation was associated with shorter duration on MV and ICU stay. Pressure Support – Continuous Positive Airway Pressure (PS-CPAP) was the most common weaning mode used followed by unplanned extubation, Non Invasive Continuous Positive Airway Pressure (NICPAP), T-piece, and sencronized intermittent mandatory ventilation. Highest rate of successful weaning was in patients with central nervous system diseases followed by respiratory diseases, cardiac diseases, and least in patients with sepsis and septic shock. Mortality rate in mechanically ventilated patients was 64%. Mortality rate was higher in patients with cardiac diseases followed by respiratory diseases, central nervous system diseases, and septic shock. Mortality was higher with higher levels of tidal volumes, higher FiO2 levels, and lower positive end-expiratory pressure levels. Mortality was higher in invasive ventilation than noninvasive ventilation. Patients with failed weaning had higher mortality. Conclusions We have demonstrated the magnitude of MV use in our ICU, the epidemiology and initial ventilation modes used, and their association with complications and in-hospital mortality.

Three cases of influenza A(H10N8) virus infection in humans have been reported; 2 of these infected persons died. Characterization of the receptor binding pattern of H10 hemagglutinin from avian and human isolates showed that both interact weakly with human-like receptors and maintain strong affinity for avian-like receptors.

The increasing demand of cycle life performance of Pb-acid batteries requires the improvement of the negative Pb electrode’s charge capacity. Electrochemical investigations were performed on Pb electrode and Pb+Carbon (Carbon black and Graphite) electrodes to evaluate the ability of the additives to enhance the electrochemical faradaic reactions that occur during the cycle of Pb-acid battery negative electrode. The electrodes were characterized through Cyclic Voltammetry (CV), Potentiodynamic Polarization (PP), and Electrochemical Impedance Spectroscopy (EIS). CV revealed that the addition of carbon on the Pb electrode increased anodic and cathodicreactions by tenfold. The kinetics of PbSO4 passivation measured through PPrevealed that the addition of Carbon on the Pb electrode accelerated the oxide formation by tenfold magnitude. The Nyquist plot measured through EIS suggest that the electrochemical mechanism and reaction kinetics is under charge-transfer. From the equivalent circuit and physical model, Pb+CB1 electrode has the lowest EIS parameters while Pb+G has the highest which is attributed to faster faradaic reaction.The Nyquist plot of the passivated Pb+CB1 electrode showed double semicircular shape. The first layer represents to the bulk passive PbSO4 layer and the second layer represents the Carbon+PbSO4 layer. The enhancements upon addition of carbon on the Pb electrode were attributed to the additive’s electrical conductivity and total surface area. The electrochemical active sites for the PbSO4 to nucleate and spread increases upon addition of electrical conductive and high surface area carbon additives.

Stainless steels may be classified according to alloy microstructure – ferritic, austenitic, martensitic, duplex, and precipitation hardening grades. Among these, austenitic grade has the largest contribution to market due to the alloy’s numerous industrial and domestic applications. In this study, the corrosion behavior of low-Nickel stainless steel in citric acid was investigated using potentiodynamic polarization techniques and Electrochemical Impedance Spectroscopy (EIS). The corrosion current density which is directly related to corrosion rate was extracted from the generated anodic polarization curve. Increasing the temperature of the citric acid resulted to increased corrosion current densities indicating higher corrosion rates at initial corrosion condition. EIS was performed to generate Nyquist plots whose shape and size depicts the corrosion mechanism and corrosion resistance of the alloy in citric acid, respectively. All the generated Nyquist plots have depressed semi-circle shapes implying that corrosion process takes place with charge-transfer as the rate-determining step. Based from the extracted values of polarization resistance (Rp), the temperature of the solution has negative correlation with the corrosion resistance of the studied alloy.

The layered transition-metal oxide Nax CoO2 has been studied extensively both for its correlated electronic properties as well as for potential battery applications. It was discovered that high-temperature Na ion vacancy order and dynamics can be very useful to tailor low-temperature properties of members of this compound family. We have studied the Na-ion dynamics on the atomic length-scale in the Na0.7 CoO2 compound by neutron spectroscopy. The temperature dependence of both the elastic and the inelastic intensities show steps at TA ≈ 290 K and TB ≈ 400 K. At TA the step is shown to be connected to low energy phonons, while at TB the Na ion diffusion suddenly gets fast enough, and the characteristic signal of quasielastic scattering appears. The current results further elucidate the subtle changes in the Na ion dynamics that have been revealed in our previous neutron diffraction studies [1], intimately connecting structural transformations at TA and TB with the opening-up of 1D and 2D Na-ion diffusion paths. Finally, the estimated diffusion coefficient above TB was found to differ from the one measured by muon-spin relaxation (μ+SR) [2] by about four orders of magnitude. However it might be that the present QENS data rather describe a fast localized prozess than a long range translational diffusion. Within this model the corresponding time scale (ℏ/E) would be in the order of 50 ps.

Chronic thrombo-embolic pulmonary hypertension (CTEPH) is a potentially curable form of pulmonary hypertension (PH) that develops in up to 3% of patients after pulmonary embolism (PE). In these patients, PE does not resolve, leading to organized fibrotic clots, with the development of precapillary PH as a result of the proximal obstruction of the pulmonary arteries. In addition, a distal microvasculopathy may also develop, contributing to the increase of pulmonary vascular resistance. Transthoracic echocardiography is the diagnostic tool that allows to establish the suspicion of PH. Ventilation-perfusion lung scintigraphy is the fundamental tool in the study of patients with suspected CTEPH; if it is normal, virtually rules out the diagnosis. Right heart catheterization is mandatory for the diagnosis of these patients. CTEPH is defined as the existence of symptoms, residual perfusion defects and precapillary PH after a minimum period of three months of anticoagulation. Pulmonary angiography helps determine the extent and surgical accessibility of thromboembolic lesions. CTEPH patients are candidates for long-term anticoagulation. Pulmonary endarterectomy is the treatment of choice, resulting in significant clinical and hemodynamic improvement. About 25% of patients have residual PH post-endarterectomy. Balloon pulmonary angioplasty is an endovascular technique that targets more distal lesions, being potentially useful for patients with inoperable CTEPH or persistent/recurrent PH post-endarterectomy. Both types of patients may also benefit from pharmacological treatment for PH. These three therapies are the cornerstone of CTEPH treatment, which has evolved towards a multimodal approach., (Copyright © 2023 The Authors. Published by Elsevier España, S.L.U. All rights reserved.)

Background: There is great interest in developing simple, user-friendly, and inexpensive tools for the quantification and elucidation of motor deficits in patients with Parkinson's disease (PD). These systems could help to monitor the clinical status of patients with PD, to develop better treatments, and to identify individuals who have subtle motor signs that might pass unnoticed in the conventional neurological examination., Methods: Mememtum, a smartphone application that allows for the quantification of several parameters of movement, such as regularity, rhythm, and changes in the number of taps while taping with a single finger and with alternating fingers, was developed and then tested in a pilot study in Madrid and in an extensive study in Quito, Ecuador., Results: Almost all patients could successfully perform single-finger tapping, but approximately 10% of patients with severe parkinsonism had problems taping with alternating fingers. The results revealed changes in the regularity of the pressure applied while tapping and a reduction in the number of taps on the device screen when alternating tapping among patients who had idiopathic PD and vascular parkinsonism compared with controls and individuals who had prediagnostic motor abnormalities of PD., Conclusion: Applications available in smartphones could be used for investigation and treatment of patients with PD, but much research is needed to optimize the ideal parameters to be investigated and the potential usefulness of this technique for patients with PD in different stages of the disease.

The pathological hallmark of Huntington disease (HD) is the intracellular aggregation of mutant huntingtin (mHTT) in striatal neurons and glia associated with the selective loss of striatal medium-sized spiny neurons. Up to the present, the role of glia in HD is poorly understood and has been classically considered secondary to neuronal disorder. Trehalose is a disaccharide known to possess many pharmacological properties, acting as an antioxidant, a chemical chaperone, and an inducer of autophagy. In this study, we analyzed at an early postnatal development stage the abnormalities observed in striatal glial cell cultures of postnatal R6/1 mice (HD glia), under baseline and stressing conditions and the protective effects of trehalose. Our data demonstrate that glial HD alterations already occur at early stages of postnatal development. After 20 postnatal days in vitro, striatal HD glia cultures showed more reactive astrocytes with increased expression of glial fibrillary acidic protein (GFAP) but with less replication capacity, less A2B5(+) glial progenitors and more microglia than wild-type (WT) cultures. HD glia had lower levels of intracellular glutathione (GSH) and was more susceptible to H2O2 and epoxomicin insults. The amount of expressed GDNF and secreted mature-BDNF by HD astrocytes were much lower than by WT astrocytes. In addition, HD glial cultures showed a deregulation of the major proteolytic systems, the ubiquitin-proteasomal system (UPS), and the autophagic pathway. This produces a defective protein quality control, indicated by the elevated levels of ubiquitination and p62 protein. Interestingly, we show that trehalose, through its capacity to induce autophagy, inhibited p62/SQSTM1 accumulation and facilitated the degradation of cytoplasmic aggregates from mHTT and α-synuclein proteins. Trehalose also reduced microglia activation and reversed the disrupted cytoskeleton of astrocytes accompanied with an increase in the replication capacity. In addition, trehalose up-regulated mature-BDNF neurotrophic factor expression and secretion, probably mediating cytoskeletal organization and helping in vesicular BDNF transport. Together, these findings indicate that glia suffers functional early changes in the disease process, changes that may contribute to HD neurodegeneration. Trehalose could be a very promising compound for treatment of HD and other diseases with abnormal protein aggregates. Furthermore our study identifies glial cells as a novel target for trehalose to induce neurotrophic and neuroprotective actions in HD., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Huntington's disease is a neurodegenerative disorder caused by an expansion of CAG repeats in the huntingtin gene which produces widespread neuronal and glial pathology. We here investigated the possible therapeutic role of glia or glial products in Huntington's disease using striatal glial conditioned medium (GCM) from fetus mice (E16) continuously infused for 15 and 30 days with osmotic minipumps into the left striatum of R6/1 mice. Animals infused with GCM had significantly less huntingtin inclusions in the ipsilateral cerebral cortex and in the ipsilateral and contralateral striata than mice infused with cerebrospinal fluid. The numbers of DARPP-32 and TH positive neurons were also greater in the ipsilateral but not contralateral striata and substantia nigra, respectively, suggesting a neuroprotective effect of GCM on efferent striatal and nigro-striatal dopamine neurons. GCM increases activity of the autophagic pathway, as shown by the reduction of autophagic substrate, p-62, and the augmentation of LC3 II, Beclin-1 and LAMP-2 protein levels, direct markers of autophagy, in GCM infused mice. GCM also increases BDNF levels. These results suggest that CGM should be further explored as a putative neuroprotective agent in Huntington's disease.

Background: Parkinson's disease (PD) is characterized by dopaminergic neurodegeneration in the substantia nigra (SN). Transforming growth factor-β1 (TGF-β1) levels increase in patients with PD, although the effects of this increment remain unclear. We have examined the mesostriatal system in adult mice deficient in Smad3, a molecule involved in the intracellular TGF-β1 signalling cascade., Results: Striatal monoamine oxidase (MAO)-mediated dopamine (DA) catabolism to 3,4-dihydroxyphenylacetic acid (DOPAC) is strongly increased, promoting oxidative stress that is reflected by an increase in glutathione levels. Fewer astrocytes are detected in the ventral midbrain (VM) and striatal matrix, suggesting decreased trophic support to dopaminergic neurons. The SN of these mice has dopaminergic neuronal degeneration in its rostral portion, and the pro-survival Erk1/2 signalling is diminished in nigra dopaminergic neurons, not associated with alterations to p-JNK or p-p38. Furthermore, inclusions of α-synuclein are evident in selected brain areas, both in the perikaryon (SN and paralemniscal nucleus) or neurites (motor and cingulate cortices, striatum and spinal cord). Interestingly, these α-synuclein deposits are detected with ubiquitin and P(S129)-α-synuclein in a core/halo cellular distribution, which resemble those observed in human Lewy bodies (LB)., Conclusions: Smad3 deficiency promotes strong catabolism of DA in the striatum (ST), decrease trophic and astrocytic support to dopaminergic neurons and may induce α-synuclein aggregation, which may be related to early parkinsonism. These data underline a role for Smad3 in α-synuclein and DA homeostasis, and suggest that modulatory molecules of this signalling pathway should be evaluated as possible neuroprotective agents.

Recent clinical studies have suggested that there is an increased risk of Alzheimer's disease (AD) in patients undergoing surgical interventions, but it is unknown whether this effect is related to anesthesia, cardiovascular complications of surgery, or associated conditions such as hypothermia. In addition, many patients, especially the elderly, present persistent post-operative cognitive deterioration after anesthesia, without clear complications during surgery. Experimental studies in animals may be helpful to dissect the pathogenic role of the different factors involved in surgery. Here, we review studies on the effects of anesthesia on neuronal function performed in tissue culture and in experimental animals. Several studies have shown that a small inhalation of anesthetics induces activation of caspases and cell toxicity on glioma and pheochromocitoma cells in culture, which is prevented by treatment with the metal chelating agent clioquinol. Exposure of old rodents to anesthesia produced memory deficits and increased levels of amyloid-β (Aβ) peptide and phosphorylated tau in brain. The effects of long term or short term repetitive exposure to small molecular weight anesthetics are more severe in transgenic AβPPswe than in wild type mice. In the former, low molecular weight increased the number of TUNEL(+) apoptotic cells and the ratio of pro-apoptotic proteins in hippocampus; reduced astroglial and increased microglial responses; increased Aβ aggregates and high molecular weight peptides; abnormal chaperone responses and reduced autophagy. In conclusion, anesthetic gases induce changes which may reproduce AD pathology in mice with mutations which produced AD. It would be interesting to know whether anesthetics are risky for subjects with special genetic risk factors.