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This study explores copyrolysis of soybean straw (SS) with hydrogen-rich tire waste (TW) to enhance pyrolytic product quality and reduce pollutant emissions. Addition of TW increased SS biomass conversion from 67.19 to 72.46% and decreased coke/residue formation from 32.81 to 27.54%. The activation energy dropped to 121.84 kJ/mol from 160.73 kJ/mol (as calculated by the Kissinger-Akahira-Sunose method) and 122.78 kJ/mol from 159.76 kJ/mol (as calculated by the Ozawa-Flynn-Wall method). Thermogravimetric analysis coupled with Fourier-transform infrared spectroscopy (TG-FTIR) showed lowered CO2, NO2, and SO2 emissions (5.58, 5.72, 3.38) compared to conventional SS pyrolysis (18.38, 11.55, 12.37). Yields of value-added chemicals (phenols, olefins, aromatics) increased (32.38, 22.17, 30.18%) versus conventional SS pyrolysis (23.56, 13.78, 20.36%). Pyrolysis gas chromatography-mass spectrometry (Py/GC-MS) analysis reveals that the addition of TW leads to a decrease in the production of oxygenates and polycyclic aromatic hydrocarbons, reducing their yields to 8.96 and 7.67%, respectively, down from 19.37 and 14.37%. Simultaneously, it enhances the yields of olefins, aromatics, phenols, and aliphatic hydrocarbons to 23.38, 26.78, 26.17, and 25.78%, respectively, compared to 15.37%, 15.29, 18.36, and 17.25%, respectively, in the absence of TW. In summary, copyrolysis of TW with SS improves product quality and reduces pollutant emissions, marking a significant research contribution.
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Congregate Nutrition Services have long been a pillar of public health assistance, championing the independence and community engagement of older Americans. The advent of COVID-19, however, restricted access to these services due to the closure of physical locations. In response, Lanakila Meals on Wheels initiated a virtual congregate meal program, Kupuna U, in collaboration with community partners in Honolulu County. The program combined grab-and-go or home-delivered meals with virtual and in-person classes to improve both nutrition and socialization for older adults. This study aimed to capture participant feedback to assess and enhance the Kupuna U program, developing it as a flexible and scalable congregate meal solution applicable nationwide. Five focus group discussions were conducted with program participants (n = 34). The majority of participants were female (74%), Asian (73%), and living alone (56%). Participants found the program beneficial, enhancing their nutrition, social engagement, and learning experiences on various topics tailored for older adults. Supportive staff played a crucial role in motivating participants to stay engaged. Participants also identified potential enhancements to the program, including more activities and courses, expanded hours, additional in-person options at various locations, and culturally tailored meals.
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COVID-19 , Grupos Focales , Servicios de Alimentación , Humanos , Femenino , Anciano , Masculino , COVID-19/prevención & control , SARS-CoV-2 , Anciano de 80 o más Años , Comidas , Hawaii , Evaluación de Programas y Proyectos de Salud/métodosRESUMEN
Hepcidin is upregulated by increased body iron stores and inflammatory cytokines. It is associated with cardiovascular events, arterial stiffness, and increased iron accumulation in human atheroma with hemorrhage. However, it is unknown whether the expression of hepcidin in human carotid plaques is related to plaque severity and whether hepcidin expression differs between men and women. Carotid samples from 58 patients (38 males and 20 females) were immunostained with hepcidin, macrophages, ferritin, and transferrin receptor. Immunocytochemistry of hepcidin was performed on THP-1 macrophages exposed to iron or 7betahydroxycholesterol. Hepcidin expression significantly increases with the progression of human atherosclerotic plaques. Plaques of male patients have significantly higher levels of hepcidin. Expressions of hepcidin are significantly correlated with the accumulation of CD68-positive macrophages and transferrin receptor 1 (TfR1) and apoptosis. In vitro, hepcidin is significantly increased in macrophages exposed to iron and moderately increased following 7-oxysterol treatment. In the cultured cells, suppression of hepcidin protected against macrophage cell death, lysosomal membrane permeabilization, and oxidative stress. Hepcidin may play a crucial role in the development and progression of atherosclerosis. The differential expression of hepcidin in male and female patients and its significant correlations with plaque severity, highlight the potential of hepcidin as a biomarker for risk stratification and therapeutic targeting in atherosclerosis.
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Aterosclerosis , Placa Aterosclerótica , Femenino , Humanos , Masculino , Aterosclerosis/metabolismo , Hepcidinas/genética , Hepcidinas/metabolismo , Hierro/metabolismo , Placa Aterosclerótica/genética , Placa Aterosclerótica/metabolismo , Receptores de Transferrina/genética , Caracteres SexualesRESUMEN
Imidacloprid (IMI), a neonicotinoid insecticide, has potential cytotoxic and genotoxic effects on human and experimental models, respectively. While being an emerging environmental contaminant, occupational exposure and related cellular mechanisms are unknown. Herein, we were motivated by a specific patient case where occupational exposure to an IMI-containing plant protection product was associated with the diagnosis of Bell's palsy. The aim was to investigate the toxic effects and cellular mechanisms of IMI exposure on glial cells (D384 human astrocytes) and on human fibroblasts (AG01518). IMI-treated astrocytes showed a reduction in cell number and dose-dependent cytotoxicity at 24 h. Lower doses of IMI induced reactive oxygen species (ROS) and lysosomal membrane permeabilisation (LMP), causing apoptosis and autophagic dysfunction, while high doses caused significant necrotic cell death. Using normal fibroblasts, we found that IMI-induced autophagic dysfunction and lysosomal damage, activated lysophagy, and resulted in a compensatory increase in lysosomes. In conclusion, the observed IMI-induced effects on human glial cells and fibroblasts provide a possible link between IMI cytotoxicity and neurological complications observed clinically in the patient exposed to this neonicotinoid insecticide.
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Insecticidas , Humanos , Insecticidas/toxicidad , Astrocitos , Estrés Oxidativo , Neonicotinoides/toxicidad , Neonicotinoides/metabolismo , Apoptosis , Lisosomas/metabolismo , FibroblastosRESUMEN
Ocean acidification is caused mainly by atmospheric carbon dioxide stored in the ocean. Ocean acidification is considered a major threat to aquatic life, and how it influences the abundance of marine fish larvae is still unclear. This research was designed to measure the current ocean acidification scenario of the Cox's Bazar coast of the Bay of Bengal, Bangladesh, and its probable influence on the abundance of fish larvae. Three research stations were selected: Bakkhali river estuary, Naf river estuary, and Rezu Khal. Monthly sampling was done, and larvae sample was collected from the surface water column (depth: 0.5 m) using a bongo net. Water parameters such as temperature, salinity, total alkalinity, and pH were determined using laboratory protocol. The seacarb package of the R programming language was used to determine ocean acidification factors. The Bakkhali river estuary showed the highest partial carbon dioxide (143.99 ± 102.27 µatm) and the lowest pH (8.27 ± 0.21). A total of 19 larvae families were identified, and the highest larval count was found in Rezu Khal (390 larvae/1000 m3), while the lowest was found in the Bakkhali river (3 larvae/1000 m3). Clupeidae, Myctophidae, and Engraulidae comprised more than 50% of the identified larvae. Blenniidae, Carangidae, Clupeidae, Engraulidae, and Gobiidae were found in all three seasons. Most of the larvae families showed the highest mean abundance under less pCO2. A negative correlation was observed between larvae and acidification factors such as pCO2, HCO3-, and dissolved inorganic carbon (DIC). The study revealed that acidification parameters of the Cox's Bazar coast were not in an acute state for the aquatic organisms' survival, but fish larvae abundance could be declined with raises in the partial carbon dioxide. The results of this study may aid in developing a management plan for conserving Bangladesh's marine and coastal fish.
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The experiment was conducted to clarify sumithion induced hematoxicity in silver barb (Barbonymus gonionotus) through in vivo exposures (25 % and 50 % of LC50 of sumithion) and subsequent recovery patterns using normal and probiotic treated feed were also assessed. Three treatments each incorporating three replications were used in the experiment for different days (1, 7, 14, 21, and 28). Treatment T1 was control (0 mg/L), and two concentrations, such as 2.61 mg/L (25 % of 96 h LC50), 5.21 mg/L (50 % of 96 h LC50) were used as Treatment T2 and T3, respectively. After 28 days of exposure to pesticide half of the fishes of T2 and T3 were reared in sumithion free water with normal (T2N, T3N) and probiotic treated feed (T2P, T3P). The median lethal concentration (50 %) for 96 h was 10.42 mg/L. In pesticide-treated groups, values of each hematological parameter (blood glucose, red blood cell, hematocrit, and hemoglobin) decreased but prevalence and severity of micronucleus and white blood cells increased significantly (p< 0.05) with concentration and time duration. Other blood indices including mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH) and mean corpuscular hemoglobin concentration (MCHC) were correspondingly changed in comparison to the control. In the recovery experiment, the silver barb recovered spontaneously, but the recovery rate was significantly higher in probiotic treated groups than normally treated groups in time and duration reliant fashion. In conclusion, persistent sublethal dosages of sumithion caused hematological abnormalities in silver barb. Probiotic supplement can recover the damage but only 28 days of recovery is not enough to recover the total alterations.
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The aim of this study was to investigate whether CD74 levels in atherosclerotic lesions are associated with inflammation, apoptosis, plaque severity, and clinical symptoms among patients with carotid atherosclerosis. We further studied whether CD74 expression is associated with apoptosis in macrophages induced by 7ketocholesterol (7keto). Sixty-one carotid samples (39 males and 22 females) were immunostained with macrophages, smooth muscle cells, CD74, ferritin, TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labeling), and thrombin receptors. Double immunocytochemistry of CD74 and caspase 3 or CD74 and Annexin V was performed on THP-1 macrophages exposed to 7keto. In human carotid plaques, CD74 expression is lesion-dependently increased and is associated with necrotic core formation and plaque rupture, clinical symptoms, macrophage apoptosis, ferritin, and thrombin receptors. CD74 levels were inversely correlated to high-density lipoproteins and statin treatment, and positively correlated to triglycerides. In THP-1 macrophages, 7keto induced a significant increase in levels of CD74, ferritin, and apoptotic cell death. This study suggests that CD74 in apoptotic macrophages is linked to inflammation and thrombosis in progression of human atherosclerotic plaques, lipid metabolism, and clinical manifestation in atherosclerosis. Surface CD74 in apoptotic macrophages and ferritin production induced by oxidized lipids may contribute to inflammation and plaque vulnerability in atherosclerosis.
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As the world tries to cope with the devastating effects of the COVID-19 pandemic and emerging variants of the virus, COVID-19 vaccination has become an even more critical tool toward normalcy. The effectiveness of the vaccination program and specifically vaccine uptake and coverage, however, is a function of an individual's knowledge and individual opinion about the disease and available vaccines. This study investigated the knowledge, attitudes, and resulting community practice(s) associated with the new COVID-19 variants and vaccines in Bangladesh, Colombia, India, Malaysia, Zimbabwe, and the USA. A cross-sectional web-based Knowledge, Attitudes, and Practices (KAP) survey was administered to respondents living in six different countries using a structured and multi-item questionnaire. Survey questions were translated into English, Spanish, and Malay to accommodate the local language in each country. Associations between KAP and a range of explanatory variables were assessed using univariate and multiple logistic regression. A total of 781 responses were included in the final analysis. The Knowledge score mean was 24 (out of 46), Attitude score 28.9 (out of 55), and Practice score 7.3 (out of 11). Almost 65% of the respondents reported being knowledgeable about COVID-19 variants and vaccination, 55% reported a positive attitude toward available COVID-19 vaccines, and 85% reported engaging in practices that supported COVID-19 vaccination. From the multiple logistic models, we found post-graduate education (AOR = 1.83, 95% CI: 1.23-2.74) and an age range 45-54 years (AOR = 5.81, 95% CI: 2.30-14.69) to be significantly associated with reported COVID-19 knowledge. In addition, positive Attitude scores were associated with respondents living in Zimbabwe (AOR = 4.49, 95% CI: 2.04-9.90) and positive Practice scores were found to be associated with people from India (AOR = 3.68, 95% CI: 1.15-11.74) and high school education (AOR = 2.16, 95% CI: 1.07-4.38). This study contributes to the identification of socio-demographic factors associated with poor knowledge, attitudes, and practices relating to COVID-19 variants and vaccines. It presents an opportunity for collaboration with diverse communities to address COVID-19 misinformation and common sources of vaccine hesitancy (i.e., knowledge, attitudes, and practices).
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BACKGROUND: Nutrition is an important predictor of an athlete's performance. It is more important for particularly those athletes who are in the growing stage (adolescents). This study aimed to assess their current level of knowledge, attitude, and practices (KAP) of nutrition and to predict potential factors impacting their level of these KAP. METHODS: A cross-sectional study was conducted among adolescent trainee athletes selected conveniently from 11 sports departments (e.g. cricket, football, hockey, etc.) of Bangladesh Krira Shikkha Protishtan (BKSP). A semi-structured interviewer-administered questionnaire was used for data collection. Anthropometric measurements (e.g. height, weight, BMI, BF %) were taken using appropriate methods. The data were analyzed using R (v3.6.1) and Python Jupyter Notebook. Descriptive statistics, t-test, analysis of variance (ANOVA), and logistic regression were used to determine the relationship between dependent and independent variables. RESULTS: A total number of 260 participants were enrolled in this study, most of them (86%) were male. Their mean age was 15.50 ± 1.83 ranging from 12-19 years. More than half of the participants had good nutrition knowledge (n = 149, 57.3%). Fifty-seven percent of participants had a positive attitude (n = 146) and 57.69% (n = 150) had a good level of practices regarding nutrition. Age (p = 0.007), gender (p = 0.004), department of training (p = 0.0034), and duration of sports training (p = 0.004) of participants were significantly associated with knowledge, while only age and BMI were significantly associated with practices. Athletes with less body fat were more likely to have good nutrition practice behavior (AOR 0.895; 95% CI 0.83, 0.96; p < 0.05) and nutrition knowledge was positively associated with nutrition practice (AOR 2.335; 95% CI 1.405, 3.88; p = 0.001). CONCLUSION: Knowledge, attitude, and practices level observed among many of our participants was satisfactory. Previous nutrition training was found as a potentially modifiable factor of good nutrition knowledge and good nutrition knowledge was found to be a predictor of good practice score. Thus, it is necessary to provide appropriate nutrition information to adolescent athletes through proper educational training and intervention on a regular basis.
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Recent concerns with pandemic outbreaks of human disease and their origins in animal populations have ignited concerns regarding connections between Emerging Infectious Diseases (EID) and development. As disasters, health, and infectious disease become part of planning concern (Matthew & McDonald, 2007), greater focus on household infrastructure and EID disease outbreaks among poultry is warranted. Following Spencer (2013), this study examines the relationship between the mix of household-scale water supplies, sanitation systems, and construction materials, and Highly Pathogenic Avian Influenza (HPAI) among poultry in a developing country: Vietnam. Findings of our multivariate logistic regressions suggest that a non-linear, Kuznets-shaped urban transition (Spencer, 2013) has an independent effect on the outbreak of HPAI, especially as it relates to household-level sanitation infrastructure. We conclude that the Kuznets-shape development of household infrastructure characteristics in Vietnam play a significant role in explaining where poultry outbreaks occur. Using secondary data from the Census of Population and Housing, and the Agricultural Census at the District and Commune levels for the country of Vietnam, we performed logistic regression to test the relationship between outbreaks of HPAI in poultry and newly-developed "coherence indices" (Spencer, 2013) of household water supply, sanitation, and construction materials that measure nonlinear, transitional development. Results show that district-scale coherence indices are negatively and independently correlated with HPAI outbreaks, especially for sanitation. Findings also suggest that community-scale coherence of urban infrastructures is a powerful tool for predicting where HPAI poultry outbreaks are likely to occur, thereby providing health planners new tools for efficient surveillance.
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Globally, reproductive health research among female sex workers (FSWs) often focuses on pregnancy prevention, but many women who sell sex aspire to have children in the future. In Bangladesh, where early marriage and parenthood is the norm, we examine reproductive histories and childbearing desires of young women who sell sex in brothels. We interviewed 1061 FSWs aged 18 to 24 in eight brothels in three Bangladesh divisions. Interviewers elicited information on sociodemographic characteristics, contraceptive use, pregnancy history, and childbearing desire. Bivariate and multivariate analyses were conducted to examine correlates of wanting to have a child within 24 months.
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Salud Reproductiva/normas , Trabajadores Sexuales/psicología , Adolescente , Bangladesh/epidemiología , Servicios de Planificación Familiar/normas , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Factores Socioeconómicos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Nymphoides is an aquatic genus consisting about 50 species,of which few were accepted as traditional medicinal plants in Asia.The literature review revealed that Nymphoides species are widely used in Ayurvedic medicine as a popular drug,i.e.Tagara.They are also utilized by the traditional local healers of different Asian countries to treat various diseases,like convulsion,jaundice,fever,headache,etc.According to thein vivo and in vitro pharmacological studies,Nymphoides species have been claimed to possess major biological activities like anticonvulsant,antioxidant,hepatoprotective,cytotoxic,antitumor,etc.Biochemical profiling of different aquatic plants of this genus revealed the presence of some important phytoehemicals as polyphenolic component,flavonoids,triterpenes,carbohydrates,glycosides,etc.Several valuable bioactive compounds including ephedrine,coumarin,secoiridoid glucosides,methyl quercetin,ferulic acid,follamenthoic acid,etc.were also known to be isolated and identified from different Nymphoides species.The aim of this review is to analyze the published report based on the medicinal values of different Asian Nymphoides species,to provide the updlated information about the ethnomedicinal,pharmacological as well as the phytochemical properties for the first time.
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Pursuing the strategy of developing potent AChE inhibitors, we attempted to carry out the N1-substitution of 2,3-dihydroquinazolin-4(1H)-one core. A set of 32 N-alkylated/benzylated quinazoline derivatives were synthesized, characterized and evaluated for their inhibition against cholinesterases. N-alkylation of the series of the compounds reported previously (N-unsubstituted) resulted in improved activity. All the compounds showed inhibition of both enzymes in the micromolar to submicromolar range. Structure activity relationship (SAR) of the 32 derivatives showed that N-benzylated compounds possess good activity than N-alkylated compounds. N-benzylated compounds 2ad and 2af were found very active with their IC50 values toward AChE in submicromolar range (0.8µM and 0.6µM respectively). Binding modes of the synthesized compounds were explored by using GOLD (Genetic Optimization for Ligand Docking) suit v5.4.1. Computational predictions of ADMET studies reveal that all the compounds have good pharmacokinetic properties with no AMES toxicity and carcinogenicity. Moreover, all the compounds are predicted to be absorbed in human intestine and also have the ability to cross blood brain barrier. Overall, the synthesized compounds have established a structural foundation for the design of new inhibitors of cholinesterase.
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Inhibidores de la Colinesterasa/farmacología , Colinesterasas/metabolismo , Quinazolinonas/farmacología , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Cristalografía por Rayos X , Relación Dosis-Respuesta a Droga , Humanos , Modelos Moleculares , Estructura Molecular , Quinazolinonas/síntesis química , Quinazolinonas/química , Relación Estructura-ActividadRESUMEN
PURPOSE: Dhaka City is home to thousands of migrants from Bangladesh's rural areas who often live in the streets. Prior studies examine street youth's practice of selling sex as a survival mechanism. We assess their less-studied practice of paying for sex and its association with sexual risk behaviors and outcomes. METHODS: As part of the global Link Up project, trained interviewers recruited 447 young men who live on the streets, ages 15-24, from seven Dhaka City "hotspots" to participate in a survey about sexual health. Among those who ever had sex, we examined frequencies and conducted bivariate analyses of sociodemographic characteristics by paying for sex status. We then conducted bivariate and multivariate logistic regression analyses of paying for sex in the last 12 months and sexual health behaviors and outcomes. RESULTS: Median participant age was 18 years. Among those who ever had sex (N = 321), 80% reported paying for sex in the last 12 months and 15% reported selling sex in the last 12 months. In multivariate analyses, those who paid for sex had significantly increased odds of reporting sexually transmitted infection-related symptoms in the last six months (adjusted odds ratio = 1.76, 95% confidence interval [CI] = 1.17-2.64) and engaging in unprotected last sex with a nonprimary partner (adjusted odds ratio = 2.19, CI = 1.58-3.03). CONCLUSIONS: The adverse factors associated with paying for sex among young men who live on the streets in Dhaka City highlight the need for programs to educate on HIV/sexually transmitted infection prevention and promote condom use, STI screening/treatment, and HIV testing in this population.
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Jóvenes sin Hogar/estadística & datos numéricos , Trabajo Sexual/estadística & datos numéricos , Sexo Inseguro/estadística & datos numéricos , Poblaciones Vulnerables , Adolescente , Adulto , Bangladesh , Estudios Transversales , Infecciones por VIH/prevención & control , Humanos , Modelos Logísticos , Masculino , Factores de Riesgo , Enfermedades de Transmisión Sexual/prevención & control , Encuestas y Cuestionarios , Migrantes/estadística & datos numéricos , Adulto JovenRESUMEN
PURPOSE: Working with health providers to reduce HIV stigma in the healthcare setting is an important strategy to improve service utilization and quality of care, especially for young people who are sexually active before marriage, are sexual minorities, or who sell sex. A stigma reduction training program for health providers in Bangladesh was evaluated. METHODS: A cohort of 300 healthcare providers were given a self-administered questionnaire, then attended a 2-day HIV and sexual and reproductive health and rights training (including a 90-minute session on stigma issues). Six months later, the cohort repeated the survey and participated in a 1-day supplemental training on stigma, which included reflection on personal values and negative impacts of stigma. A third survey was administered 6 months later. A cross-sectional survey of clients age 15-24 years was implemented before and after the second stigma training to assess client satisfaction with services. RESULTS: Provider agreement that people living with HIV should be ashamed of themselves decreased substantially (35.3%-19.7%-16.3%; p < .001), as did agreement that sexually active young people (50.3%-36.0%-21.7%; p < .001) and men who have sex with men (49.3%-38.0%-24.0%; p < .001) engage in "immoral behavior." Young clients reported improvement in overall satisfaction with services after the stigma trainings (63.5%-97.6%; p < .001). CONCLUSIONS: This study indicates that a targeted stigma reduction intervention can rapidly improve provider attitudes and increase service satisfaction among young people. More funding to scale up these interventions is needed.
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Actitud del Personal de Salud , Satisfacción del Paciente , Derechos Sexuales y Reproductivos/educación , Estigma Social , Estereotipo , Adolescente , Adulto , Bangladesh , Estudios Transversales , Femenino , Infecciones por VIH/psicología , Humanos , Masculino , Trabajo Sexual/estadística & datos numéricos , Conducta Sexual/psicología , Encuestas y Cuestionarios , Adulto JovenRESUMEN
In search of potent inhibitors of cholinesterases, we have synthesized and evaluate a number of 2,3-dihydroquinazolin-4(1H)-one derivatives. The synthetic approach provided an efficient synthesis of the target molecules with excellent yield. All the tested compounds showed activity against both the enzymes in micromolar range. In many case, the inhibition of both enzymes are higher than or comparable to the standard drug galatamine. With the selectivity index of 2.3 for AChE, compound 5f can be considered as a potential lead compound with a feature of dual AChE/BChE inhibition with IC50=1.6±0.10µM (AChE) and 3.7±0.18µM (BChE). Binding modes of the synthesized compounds were explored by using GOLD (Genetic Optimization for Ligand Docking) suit v5.4.1. The computed binding modes of these compounds in the active site of AChE and BChE provide an insight into the mechanism of inhibition of these two enzyme.
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Inhibidores de la Colinesterasa/química , Inhibidores de la Colinesterasa/farmacología , Quinazolinonas/química , Quinazolinonas/farmacología , Acetilcolinesterasa/metabolismo , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/enzimología , Animales , Butirilcolinesterasa/metabolismo , Inhibidores de la Colinesterasa/síntesis química , Electrophorus , Caballos , Humanos , Simulación del Acoplamiento Molecular , Quinazolinonas/síntesis química , Relación Estructura-ActividadRESUMEN
Autophagy dysfunction in mouse atherosclerosis models has been associated with increased lipid accumulation, apoptosis and inflammation. Expression of cystatin C (CysC) is decreased in human atheroma, and CysC deficiency enhances atherosclerosis in mice. Here, we first investigated the association of autophagy and CysC expression levels with atheroma plaque severity in human atherosclerotic lesions. We found that autophagy proteins Atg5 and LC3ß in advanced human carotid atherosclerotic lesions are decreased, while markers of dysfunctional autophagy p62/SQSTM1 and ubiquitin are increased together with elevated levels of lipid accumulation and apoptosis. The expressions of LC3ß and Atg5 were positively associated with CysC expression. Second, we investigated whether CysC expression is involved in autophagy in atherosclerotic apoE-deficient mice, demonstrating that CysC deficiency (CysC(-/-) ) in these mice results in reduction of Atg5 and LC3ß levels and induction of apoptosis. Third, macrophages isolated from CysC(-/-) mice displayed increased levels of p62/SQSTM1 and higher sensitivity to 7-oxysterol-mediated lysosomal membrane destabilization and apoptosis. Finally, CysC treatment minimized oxysterol-mediated cellular lipid accumulation. We conclude that autophagy dysfunction is a characteristic of advanced human atherosclerotic lesions and is associated with reduced levels of CysC. The deficiency of CysC causes autophagy dysfunction and apoptosis in macrophages and apoE-deficient mice. The results indicate that CysC plays an important regulatory role in combating cell death via the autophagic pathway in atherosclerosis.
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Aterosclerosis/metabolismo , Aterosclerosis/patología , Autofagia , Cistatina C/metabolismo , Macrófagos/metabolismo , Macrófagos/patología , Anciano , Animales , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Línea Celular , Cistatina C/deficiencia , Progresión de la Enfermedad , Humanos , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Lisosomas/efectos de los fármacos , Lisosomas/metabolismo , Macrófagos/efectos de los fármacos , Ratones , Permeabilidad , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/patología , Proteínas Recombinantes/farmacologíaRESUMEN
7-Oxysterols are major toxic components in oxidized low-density lipoprotein and human atheroma lesions, which cause lysosomal membrane permeabilization (LMP) and cell death. Autophagy may function as a survival mechanism in this process. Here, we investigated whether 7-oxysterols mixed in an atheroma-relevant proportion induce autophagy, whether autophagy induction influences 7-oxysterol-mediated cell death, and the underlying mechanisms, by focusing on cellular lipid levels, oxidative stress, and LMP in 7-oxysterol-treated macrophages. We found that 7-oxysterols induced cellular lipid accumulation, autophagy dysfunction, and cell death in the form of both apoptosis and necrosis. Exposure to 7-oxysterols induced autophagic vacuole synthesis in the form of increased autophagy marker microtubule-associated protein 1A/1B-light chain 3 (LC3) and LC3-phosphatidylethanolamine conjugate (LC3-II) and autophagic vacuole formation. This led to an accumulation of p62, indicating a reduction in autophagic vacuole degradation. Importantly, autophagy induction significantly reduced 7-oxysterol-mediated cell death by diminishing LMP and oxidative stress. Moreover, autophagy induction minimized cellular lipid accumulation induced by 7-oxysterols. These findings highlight the importance of autophagy in combating cellular stress, LMP, and cell death in atherosclerosis. Therefore, activation of the autophagy pathway may be a potential therapeutic strategy for prevention of necrotic core formation in atherosclerotic lesions.
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The reaction of cyclobutane-1,2-dione with hydroxide was studied by a variety of ab initio (MP2, SCS-MP2, CCSD(T), CEPA/1) and density functional (M06-2X) methods. Three possible reaction paths of the initially formed tetrahedral adduct leading to either 1-hydroxycyclopropane-1-carboxylate (benzilic acid type rearrangement, path A), α-oxobutanoate (path B) or γ-oxobutanoate (path C) were considered. Although the latter two products show similar or even more negative Gibbs free energies of reaction than calculated for the benzilic acid type rearrangement, the Gibbs free energies of activation are substantially higher. According to the calculations, the only feasible reaction appears to be the formation of 1-hydroxycyclopropane-1-carboxylate, which is corroborated by previous experimental observations.
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Oxysterol accumulation and p53 expression mainly in macrophages have been associated with cell death and necrotic core formation in human atheroma progression. Oxidative stress and lysosomal membrane permeabilization (LMP) in macrophages are important causes of macrophage apoptosis. However, it is not understood how p53 and oxysterols interact in the process. We show here that 7-oxysterols induce endogenous full-length p53 and phospho-p53 (p53-Ser15) in both nucleus and cytoplasm of THP1 and J774 cells, which is followed by cellular oxidative stress and apoptotic cell death. The role of p53 in 7-oxysterol-mediated cell death is further investigated in temperature sensitive p53-transfected (M1-t-p53) and in p53-deficient (M1) cells. These results reveal that 7-oxysterols induce induction and nuclear translocation of p53 in M1-t-p53 cells, which in turn enhances LMP, mitochondrial translocation of Bax, mitochondrial membrane permeabilization, cytosolic release of cytochrome c, and cell death. Most importantly, the above effects of 7-oxysterols were not observed in p53-deficient M1 cells. The findings reveal that 7-oxysterol-induced cell death occurs via p53-dependent pathways. Subsequent p53 nuclear translocation and induction of wild-type and phosphorylated p53 are early steps in oxysterol-induced lysosomal-mitochondrial pathways involved in cell death.