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Abstract The main aim of the paper is to assess whether vitamin C, vitamin D, and natural honey can be administered in the course of the COVID-19 pandemic for promising in line methods with recent evidence. Both systematic literature and clinical trial identification were conducted by searching various databases. A total 58 articles and 29 clinical trials were selected wherein 11 for vitamin C, 16 for vitamin D, and 2 for natural honey were identified for analysis. The high doses of vitamin C (i.e. '200 mg/kg body weight/day, divided into 4 doses') has been found to reduce COVID-19 lung damage, various flu infections. Additionally, the high doses of vitamin C can shorten around 7.8% stay in the intensive care unit. At the same time, vitamin D can effectively protect from lung injury and acute respiratory infections whereas vitamin D deficiency severely affects 75% of the institutionalized people (serum 25(OH) D < 25 nmol/L). Meanwhile, natural honey which contains proteins (0.1-0.4%); ash (0.2%); water (15-17%) has potential antiviral effects and the ability to improve immunity. Therefore, the administration of vitamins and honey is the promising evidence-based approach for reducing fatalities, saving lives, and bringing the COVID-19 pandemic to a rapid end. It is believed that the utilization of vitamin C, vitamin D, and natural honey with the current treatment may be effective in treating COVID-19-caused fatal complications such as pneumonia. Therefore, high-level clinical studies are required on COVID-19 to administrate the effects of vitamins and natural honey
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Vitaminas/efectos adversos , Tratamiento Farmacológico de COVID-19/clasificación , Miel/efectos adversos , Antivirales/administración & dosificación , Neumonía/complicaciones , Ácido Ascórbico/efectos adversos , Vitamina D/efectos adversos , COVID-19/prevención & controlRESUMEN
New wireless network paradigms will demand higher spectrum use and availability to cope with emerging data-hungry devices. Traditional static spectrum allocation policies cause spectrum scarcity, and new paradigms such as Cognitive Radio (CR) and new protocols and techniques need to be developed in order to have efficient spectrum usage. Medium Access Control (MAC) protocols are accountable for recognizing free spectrum, scheduling available resources and coordinating the coexistence of heterogeneous systems and users. This paper provides an ample review of the state-of-the-art MAC protocols, which mainly focuses on Cognitive Radio Ad Hoc Networks (CRAHN). First, a description of the cognitive radio fundamental functions is presented. Next, MAC protocols are divided into three groups, which are based on their channel access mechanism, namely time-slotted protocol, random access protocol and hybrid protocol. In each group, a detailed and comprehensive explanation of the latest MAC protocols is presented, as well as the pros and cons of each protocol. A discussion on future challenges for CRAHN MAC protocols is included with a comparison of the protocols from a functional perspective.
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The objective of this study was to investigate the mechanism of heat shock protein 90 alpha (Hsp90α) protection against heart damage resulting from heat stress by detecting Hsp90α mRNA, Hsp90α protein, protein localization, and cell damage in primary myocardial cells of neonatal rats in response to heat stress in vitro. The cells were heat-stressed at 42°C in an incubator with 95% air and 5% CO2 for different periods. Levels of Hsp90α, protein localization, enzymes, and cytopathological lesions were detected using Western blot, immunocytochemistry enzymatic assays, and cytopathological techniques. Aspartate aminotransferase, lactate dehydrogenase, and creatine kinase enzyme levels were elevated during heat stress, and acute cellular lesions that were characterized by vacuolar degeneration and necrosis were observed. Hsp90α levels decreased between 10 and 60 min of heat stress and increased after 360 and 480 min, while Hsp90α mRNA decreased after 360 min. These results indicate that heat stress might induce irreversible damage in certain myocardial cells. The elevated Hsp90α level at the end of heat stress and its positive signal in the cytoplasm of myocardial cells after heat stress could be associated with its protective role. Additionally, the consumption of Hsp90α exceeded its production in the first period of treatment.
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Regulación del Desarrollo de la Expresión Génica , Proteínas HSP90 de Choque Térmico/biosíntesis , Respuesta al Choque Térmico/genética , Miocitos Cardíacos/metabolismo , Animales , Proteínas HSP90 de Choque Térmico/genética , Calor , Técnicas In Vitro , Miocardio/citología , Miocitos Cardíacos/citología , ARN Mensajero/biosíntesis , RatasRESUMEN
OBJECTIVE: To improve gait and balance in patients with Parkinson's disease by combining anodal transcranial direct current stimulation with physical training. DESIGN: In a double-blind design, one group (physical training; n = 8) underwent gait and balance training during transcranial direct current stimulation (tDCS; real/sham). Real stimulation consisted of 15 minutes of 2 mA transcranial direct current stimulation over primary motor and premotor cortex. For sham, the current was switched off after 30 seconds. Patients received the opposite stimulation (sham/real) with physical training one week later; the second group (No physical training; n = 8) received stimulation (real/sham) but no training, and also repeated a sequential transcranial direct current stimulation session one week later (sham/real). SETTING: Hospital Srio Libanes, Buenos Aires, Argentina. SUBJECTS: Sixteen community-dwelling patients with Parkinson's disease. INTERVENTIONS: Transcranial direct current stimulation with and without concomitant physical training. MAIN MEASURES: Gait velocity (primary gait outcome), stride length, timed 6-minute walk test, Timed Up and Go Test (secondary outcomes), and performance on the pull test (primary balance outcome). RESULTS: Transcranial direct current stimulation with physical training increased gait velocity (mean = 29.5%, SD = 13; p < 0.01) and improved balance (pull test: mean = 50.9%, SD = 37; p = 0.01) compared with transcranial direct current stimulation alone. There was no isolated benefit of transcranial direct current stimulation alone. Although physical training improved gait velocity (mean = 15.5%, SD = 12.3; p = 0.03), these effects were comparatively less than with combined tDCS + physical therapy (p < 0.025). Greater stimulation-related improvements were seen in patients with more advanced disease. CONCLUSIONS: Anodal transcranial direct current stimulation during physical training improves gait and balance in patients with Parkinson's disease. Power calculations revealed that 14 patients per treatment arm (α = 0.05; power = 0.8) are required for a definitive trial.
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Terapia por Ejercicio/métodos , Trastornos Neurológicos de la Marcha/rehabilitación , Enfermedad de Parkinson/rehabilitación , Equilibrio Postural/fisiología , Estimulación Transcraneal de Corriente Directa/métodos , Anciano , Terapia Combinada , Método Doble Ciego , Femenino , Estudios de Seguimiento , Marcha/fisiología , Trastornos Neurológicos de la Marcha/etiología , Trastornos Neurológicos de la Marcha/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico , Proyectos Piloto , Recuperación de la Función , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
To understand the mechanism underlying the sudden animal death caused by acute heart failure during heat stress, the relationships among the heat-induced pathological changes and apoptosis and the variations in the levels of protective Hsp90α and its mRNA in the heat-stressed primary myocardial cells of neonatal rats in vitro were studied by cytopathological observation, immunoblotting, RT-PCR, and analysis of the related enzymes. After a period of adaptive cell culture, the myocardial cells were immediately exposed to heat stress at 42°C for 10, 20, 40, 60, 120, 240, 360, and 480 min. Levels of creatine kinase increased from the beginning of heat stress, and the cells exposed to heat stress showed acute cellular lesions characterized by vacuolar degeneration and necrosis after 40 min of heat stress, suggesting that the myocardial cells in vitro were obviously stressed and damaged by higher temperature. The levels of cleaved caspase-3 and cytochrome C, which were related to apoptosis, increased significantly after 40 min of heat stress while the Hsp90α protein level significantly decreased. In contrast, after 6 h of exposure to heat stress, the levels of cleaved caspase-3 and cytochrome C decreased while those of Hsp90α significantly increased, suggesting that early depletion of Hsp90α coincides with a high rate of necrosis and apoptosis in heat-stressed myocardial cells, while the Hsp90α level in surviving cells increases again with significantly less apoptosis after 6 h of heat stress. These findings also indicate that apoptosis of myocardial cells occurs through the activation of the cytochrome C and caspase-3 pathway. The cell repair capacity of Hsp90α is overstrained in the early phase of heat treatment and needs some hours to stabilize. As a result, in the primary myocardial cells in vitro, Hsp90α shows protective activity against damage at the end period of the heat exposure.
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Apoptosis , Proteínas HSP90 de Choque Térmico/fisiología , Respuesta al Choque Térmico , Miocitos Cardíacos/fisiología , Animales , Animales Recién Nacidos , Caspasa 3/metabolismo , Tamaño de la Célula , Supervivencia Celular , Células Cultivadas , Creatina Quinasa/metabolismo , Citocromos c/metabolismo , Expresión Génica , Cultivo Primario de Células , RatasRESUMEN
As a prerequisite for area-wide application of the sterile insect technique in an area encompassing northern Argentina and southern Brazil, prezygotic and postzygotic reproductive compatibility among three geographically distant populations in the area was tested. In field cages, sexually mature adults of each population were found to be sexually compatible, mating duration was not affected by fly origin and there was no clear evidence of spatial partition of mating location. In the laboratory, homotypic and heterotypic crosses for all possible combinations displayed similar levels of fertility and yielded F1 adults without distortion of the sex ratio. Finally, F1 hybrid and parental adults produced equally viable F2 eggs. Put together, our results and those from earlier studies suggest that a large area, ranging from Buenos Aires to the surroundings of São Paulo, could be managed using a single A. fraterculus mass-reared strain. At the northern margin of this area, two A. fraterculus morphotypes appear to coexist in sympatry. We delineate future research to further delimit the distribution of the aff1 morphotype (Argentina-southern Brazil) and to gain insight into evolutionary patterns producing divergence and radiation of tropical fruit fly species.
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Reproducción/fisiología , Tephritidae/fisiología , Distribución Animal , Animales , Argentina , Brasil , Femenino , Masculino , Control Biológico de Vectores/métodos , Reproducción/genética , Conducta Sexual Animal , Tephritidae/genéticaRESUMEN
We investigated and described the kinetics of heat shock protein (Hsp) 110 expression and distribution in rat primary myocardial cells exposed to heat stress in vitro. After incubation at 37°C for 72 h, myocardial cells were heat stressed at 42°C for 0, 10, 20, 40, 60, 120, 240, 360, and 480 min. Significant increases in aspartate transaminase, lactate dehydrogenase, and creatine kinase enzymatic activities in the myocardial cell culture media were observed during heat stress, suggesting that the integrity of the myocardial cells was altered. Immunocytochemical analysis revealed that the expressed Hsp110 was constitutively localized in the cytoplasm and in the nuclei in small amounts characterized by a granular pattern. Nuclear Hsp110 levels increased significantly after 240 min of heat stress compared with levels in the control. The overall levels of Hsp110 expression increased significantly after 20 min. After 240 min, Hsp110 levels were approximately 1.2-fold higher than those in the control. Increasing levels of hsp110 messenger RNA detected using real-time quantitative polymerase chain reaction were observed after 20 min of heat stress, and the levels peaked with a 10-fold increase after 240 min of heat stress. These results indicate that the expression of Hsp110 in primary myocardial cells in vitro is sensitive to hyperthermic stress and that Hsp110 is involved in the potential acquisition of thermotolerance after heat stress. Therefore, Hsp110 might play a fundamental role in opposing and alleviating heat-induced damage caused by hyperthermic stress in primary myocardial cells.
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Regulación de la Expresión Génica , Proteínas del Choque Térmico HSP110/metabolismo , Miocitos Cardíacos/metabolismo , Animales , Aspartato Aminotransferasas/metabolismo , Células Cultivadas , Creatina Quinasa/metabolismo , Medios de Cultivo Condicionados , Expresión Génica , Proteínas del Choque Térmico HSP110/genética , Respuesta al Choque Térmico , Cinética , L-Lactato Deshidrogenasa/metabolismo , Cultivo Primario de Células , ARN Mensajero/genética , ARN Mensajero/metabolismo , RatasRESUMEN
Recent fears of terrorism have provoked an increase in delays and denials of transboundary shipments of radioisotopes. This represents a serious constraint to sterile insect technique (SIT) programs around the world as they rely on the use of ionizing radiation from radioisotopes for insect sterilization. To validate a novel X ray irradiator, a series of studies on Ceratitis capitata (Wiedemann) and Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae) were carried out, comparing the relative biological effectiveness (RBE) between X rays and traditional gamma radiation from 60Co. Male C. capitata pupae and pupae of both sexes of A. fraterculus, both 24-48 h before adult emergence, were irradiated with doses ranging from 15 to 120 Gy and 10-70 Gy, respectively. Estimated mean doses of 91.2 Gy of X and 124.9 Gy of gamma radiation induced 99% sterility in C. capitata males. Irradiated A. fraterculus were 99% sterile at approximately 40-60 Gy for both radiation treatments. Standard quality control parameters and mating indices were not significantly affected by the two types of radiation. The RBE did not differ significantly between the tested X and gamma radiation, and X rays are as biologically effective for SIT purposes as gamma rays are. This work confirms the suitability of this new generation of X ray irradiators for pest control programs that integrate the SIT.
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Ceratitis capitata/efectos de la radiación , Control Biológico de Vectores/métodos , Tephritidae/efectos de la radiación , Animales , Relación Dosis-Respuesta en la Radiación , Masculino , Rayos XRESUMEN
Se adiestró a consejeras en materia de lactancia materna para que dieran asesoramiento a las madres de lactantes parcialmente amamantados y hospitalizados por diarrea, con el fin de lograr que las madres iniciaran la lactancia materna exclusiva durante su permanencia en el hospital. Se asignó de forma aleatoria a lactantes (n = 250) de 12 meses de edad o menos a un grupo de intervención y a un grupo testigo. Las madres del grupo de intervención fueron asesoradas individualmente por las consejeras, mientras que las madres del grupo testigo recibieron solo la educación sanitaria impartida en grupo rutinariamente. Durante el seguimiento que hicieron las consejeras en el hogar una semana más tarde, solo las madres del grupo de intervención fueron asesoradas. A las 2 semanas de su egreso, todas las madres fueron evaluadas en términos de sus prácticas de amamantamiento en el hogar. En cuanto a los 125 pares de madres e hijos que había en cada grupo, 60% de las madres del grupo de intervención alimentaban a sus hijos al pecho exclusivamente en el momento del egreso, en comparación con solo 6% de las madres del grupo testigo (P < 0,001); 2 semanas más tarde, estos porcentajes subieron a 75 y 8 en el grupo de intervención y en el grupo testigo, respectivamente (P < 0,001). Sin embargo, 49% de las madres del grupo testigo volvieron a alimentar a sus hijos con biberón, en comparación con 12% de las madres del grupo de intervención (P < 0,001). Por consiguiente, la orientación individual tuvo un efecto favorable en las madres, ya que hizo que iniciaran la lactancia materna exclusiva durante la hospitalización y que la siguieran practicando en el hogar. Los centros de salud maternoinfantil deben incluir la orientación sobre lactancia materna como parte integral de sus programas para mejorar las prácticas de alimentación de los lactantes.
Lactation counsellors were trained to advise mothers of partially breast-fed infants who were admitted to hospital because of diarrhoea, so that they could start exclusive breast-feeding during their hospital stay. Infants (n = 250) up to 12 weeks of age were randomized to intervention and control groups. Mothers in the intervention group were individually advised by the counsellors while mothers in the control group received only routine group health education. During follow-up at home by the counsellors a week later, only the mothers in the intervention group were counselled. All the mothers were evaluated for infant feeding practices at home two weeks after discharge. Among the 125 motherinfant pairs in each group, 60% of mothers in the intervention group were breast-feeding exclusively at discharge compared with only 6% in the control group (P < 0.001); two weeks later, these rates rose to 75% and 8% in the intervention and control groups, respectively (P < 0.001). However, 49% of mothers in the control group reverted back to bottle-feeding compared with 12% in the intervention group (P < 0.001). Thus, individual counselling had a positive impact on mothers to start exclusive breast-feeding during hospitalization and to continue the practice at home. Maternal and child health facilities should include lactation counselling as an integral part of their programmes to improve infant feeding practices.
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Humanos , Femenino , Recién Nacido , Lactante , Lactancia Materna , Diarrea/dietoterapia , Leche Humana/fisiología , Madres/educación , Evaluación de Procesos y Resultados en Atención de Salud , Recolección de Datos/métodosAsunto(s)
Diarrea/sangre , Vitamina A/sangre , Enfermedad Aguda , Administración Oral , Niño , Preescolar , Diarrea/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Humanos , Prealbúmina/análisis , Proteínas de Unión al Retinol/sangre , Vitamina A/administración & dosificación , Vitamina A/uso terapéuticoRESUMEN
Giardia lamblia infection in an endemic area was investigated by following a cohort of 33 lactating mothers and their infants in a semiurban community of Bangladesh for one year. Eighty-two percent of mothers and 42% of infants excreted Giardia at least once during the study period. Infants became infected as early as 3 months of age, and 86% of the infected infants had diarrhea, suggesting that the first exposure to the parasite results in disease. Only one of the infected mothers had diarrhea, indicating that with repeated exposure to Giardia, mothers in an endemic area may develop partial immunity that protects against disease but not infection. An interrelationship between maternal and infant colonization was not found. Local and systemic immune responses to Giardia correlated poorly with infection, but milk antibodies were a better reflection of infection than serum antibodies were. Infection with G. lamblia was significantly lower in infants younger than 6 months (9%), an age when many are totally breast-fed. However, we were unable to establish clear-cut protection related to human milk antibodies, and suggest that the lower infection rate in younger infants results mainly from decreased exposure to Giardia cysts.
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Anticuerpos/análisis , Giardiasis/inmunología , Adolescente , Adulto , Bangladesh , Femenino , Estudios de Seguimiento , Giardiasis/genética , Giardiasis/parasitología , Humanos , Lactante , Recién Nacido , Masculino , Leche Humana/inmunología , Saliva/inmunologíaRESUMEN
We performed a double-blind trial comparing sucrose electrolyte oral solution with glucose electrolyte oral solution in children less than 5 years of age with severe cholera-like diarrhea. Of 111 patients studied (102 with bacteriologically confirmed cholera), 55 received sucrose solution and 56 received glucose solution. The success rates, as defined by the absence of the need to give unscheduled intravenous therapy, were similar in the two groups (73% and 77% in the sucrose and glucose groups, respectively). There was no difference in purging rates between the two groups. The primary determinant of success for oral fluid regardless of the sugar was the purging rate. Sucrose malabsorption was responsible for oral therapy failure in one child. This study demonstrates that sucrose is an effective alternative to glucose in the oral therapy solution, but either must be used in conjunction with intravenous solution when treating severe dehydrating diarrhea.
PIP: This study compared, in children with cholera-like severe diarrhea, an oral glucose-electrolyte solution with an oral sucrose-electrolyte solution in equimolar amounts (WHO formula) in a double-blind manner. Of 111 patients, 55 were given sucrose and 56 glucose solutions. An absence of the need to use unscheduled intravenous therapy defined the success rate, which was similar in both groups: 73 and 77%, respectively, in the sucrose and glucose groups. Purgation rates also showed no difference between groups. The main determinant of success for oral fluid regardless of the sugar used was the purging rate. 1 failure of therapy in the sucrose group was attributed to sucrose malabsorption. It is concluded that sucrose is an effective alternative to glucose for oral rehydration therapy, but if the diarrhea has caused severe dehydration before the start of treatment, intravenous supplementation must also be used.