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Development of effective human immunodeficiency virus 1 (HIV-1) vaccines requires synergy between innate and adaptive immune cells. Here we show that induction of the transcription factor CREB1 and its target genes by the recombinant canarypox vector ALVAC + Alum augments immunogenicity in non-human primates (NHPs) and predicts reduced HIV-1 acquisition in the RV144 trial. These target genes include those encoding cytokines/chemokines associated with heightened protection from simian immunodeficiency virus challenge in NHPs. Expression of CREB1 target genes probably results from direct cGAMP (STING agonist)-modulated p-CREB1 activity that drives the recruitment of CD4+ T cells and B cells to the site of antigen presentation. Importantly, unlike NHPs immunized with ALVAC + Alum, those immunized with ALVAC + MF59, the regimen in the HVTN702 trial that showed no protection from HIV infection, exhibited significantly reduced CREB1 target gene expression. Our integrated systems biology approach has validated CREB1 as a critical driver of vaccine efficacy and highlights that adjuvants that trigger CREB1 signaling may be critical for efficacious HIV-1 vaccines.
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Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/imunologia , Infecções por HIV/imunologia , HIV-1/imunologia , Imunogenicidade da Vacina/imunologia , Vacinas Virais/imunologia , Vacinas contra a AIDS/imunologia , Adjuvantes Imunológicos/farmacologia , Animais , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Expressão Gênica/imunologia , Vetores Genéticos/imunologia , Anticorpos Anti-HIV/imunologia , Infecções por HIV/virologia , Humanos , Imunização/métodos , Primatas/imunologia , Primatas/virologia , Vacinação/métodosRESUMO
In cancer cells, endogenous or therapy-induced DNA damage leads to the abnormal presence of DNA in the cytoplasm, which triggers the activation of cGAS (cyclic GMP-AMP synthase) and STING (stimulator of interferon genes). STAT2 suppresses the cGAMP-induced expression of IRF3-dependent genes by binding to STING, blocking its intracellular trafficking, which is essential for the full response to STING activation. STAT2 reshapes STING signaling by inhibiting the induction of IRF3-dependent, but not NF-κB-dependent genes. This noncanonical activity of STAT2 is regulated independently of its tyrosine phosphorylation but does depend on the phosphorylation of threonine 404, which promotes the formation of a STAT2:STING complex that keeps STING bound to the endoplasmic reticulum (ER) and increases resistance to DNA damage. We conclude that STAT2 is a key negative intracellular regulator of STING, a function that is quite distinct from its function as a transcription factor.
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Proteínas de Membrana , Nucleotidiltransferases , Proteínas Serina-Treonina Quinases , Fator de Transcrição STAT2 , DNA/metabolismo , Dano ao DNA , Nucleotidiltransferases/metabolismo , Fosforilação , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Fator de Transcrição STAT2/metabolismo , Proteínas de Membrana/metabolismoRESUMO
Pre-mRNA splicing is a significant step for post-transcriptional modifications and functions in a wide range of physiological processes in plants. Human NHP2L binds to U4 snRNA during spliceosome assembly; it is involved in RNA splicing and mediates the development of human tumors. However, no ortholog has yet been identified in plants. Therefore, we report At4g12600 encoding the ortholog NHP2L protein, and AtSNU13 associates with the component of the spliceosome complex; the atsnu13 mutant showed compromised resistance in disease resistance, indicating that AtSNU13 is a positive regulator of plant immunity. Compared to wild-type plants, the atsnu13 mutation resulted in altered splicing patterns for defense-related genes and decreased expression of defense-related genes, such as RBOHD and ALD1. Further investigation shows that AtSNU13 promotes the interaction between U4/U6.U5 tri-snRNP-specific 27 K and the motif in target mRNAs to regulate the RNA splicing. Our study highlights the role of AtSNU13 in regulating plant immunity by affecting the pre-mRNA splicing of defense-related genes.
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Proteínas de Arabidopsis , Arabidopsis , Imunidade Vegetal , Precursores de RNA , Splicing de RNA , Arabidopsis/genética , Arabidopsis/imunologia , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Imunidade Vegetal/genética , Precursores de RNA/genética , Precursores de RNA/metabolismo , Spliceossomos/metabolismo , Spliceossomos/genéticaRESUMO
RNA silencing is an innate immune mechanism of plants against invasion by viral pathogens. Artificial microRNA (amiRNA) can be engineered to specifically induce RNA silencing against viruses in transgenic plants and has great potential for disease control. Here, we describe the development and application of amiRNA-based technology to induce resistance to soybean mosaic virus (SMV), a plant virus with a positive-sense single-stranded RNA genome. We have shown that the amiRNA targeting the SMV P1 coding region has the highest antiviral activity than those targeting other SMV genes in a transient amiRNA expression assay. We transformed the gene encoding the P1-targeting amiRNA and obtained stable transgenic Nicotiana benthamiana lines (amiR-P1-3-1-2-1 and amiR-P1-4-1-2-1). Our results have demonstrated the efficient suppression of SMV infection in the P1-targeting amiRNA transgenic plants in an expression level-dependent manner. In particular, the amiR-P1-3-1-2-1 transgenic plant showed high expression of amiR-P1 and low SMV accumulation after being challenged with SMV. Thus, a transgenic approach utilizing the amiRNA technology appears to be effective in generating resistance to SMV.
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Resistência à Doença , MicroRNAs , Nicotiana , Doenças das Plantas , Plantas Geneticamente Modificadas , Potyvirus , MicroRNAs/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/virologia , Plantas Geneticamente Modificadas/imunologia , Nicotiana/genética , Nicotiana/virologia , Nicotiana/imunologia , Doenças das Plantas/virologia , Doenças das Plantas/genética , Doenças das Plantas/imunologia , Resistência à Doença/genética , Potyvirus/patogenicidade , Potyvirus/genética , Interferência de RNA , Glycine max/genética , Glycine max/virologia , Glycine max/imunologiaRESUMO
Melanoma is the deadliest of skin cancers and has a high tendency to metastasize to distant organs. Calcium and metabolic signals contribute to melanoma invasiveness; however, the underlying molecular details are elusive. The MCU complex is a major route for calcium into the mitochondrial matrix but whether MCU affects melanoma pathobiology was not understood. Here, we show that MCUA expression correlates with melanoma patient survival and is decreased in BRAF kinase inhibitor-resistant melanomas. Knockdown (KD) of MCUA suppresses melanoma cell growth and stimulates migration and invasion. In melanoma xenografts, MCUA_KD reduces tumor volumes but promotes lung metastases. Proteomic analyses and protein microarrays identify pathways that link MCUA and melanoma cell phenotype and suggest a major role for redox regulation. Antioxidants enhance melanoma cell migration, while prooxidants diminish the MCUA_KD -induced invasive phenotype. Furthermore, MCUA_KD increases melanoma cell resistance to immunotherapies and ferroptosis. Collectively, we demonstrate that MCUA controls melanoma aggressive behavior and therapeutic sensitivity. Manipulations of mitochondrial calcium and redox homeostasis, in combination with current therapies, should be considered in treating advanced melanoma.
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Cálcio , Melanoma , Humanos , Cálcio/metabolismo , Proteômica , Melanoma/genética , Melanoma/metabolismo , Oxirredução , Fenótipo , Linhagem Celular TumoralRESUMO
Economy of Pakistan is heavily dependent upon agriculture and extensive use of pesticide is quiet common to enhance the crop yield. Imidacloprid is among the first choice pesticides in Pakistan and it has been reported that through run off along with water it ends up in water bodies affecting non target aquatic fauna. Through the present investigation, we are reporting the effects of Imidacloprid on the fatty acids composition of a non-target, commercially important carp: Labeo rohita. Fish were exposed to sub lethal concentration of Imidacloprid (120 mgL1) for 2, 4 and 8 days (short term) as well as for 16, 32 and 64 days (long term experimental conditions). Pesticide untreated controls were also maintained for each treatment. Following the specific Imidacloprid exposure, fatty acid composition (%) was determined in the muscle of all experimental groups by using gas chromatography. Fish exposed to Imidacloprid for 8 days had reduced Palmitic acid (p = 0.02) and elevated muscle Arachidic acid (p < 0.001) than control group. Labeo rohita exposed to the pesticide for 32 days had elevated muscle Oleic (p = 0.02) and Linoleic acid (p = 0.02) while fish exposed to Imidacloprid to 64 days had reduced muscle Palmitic (p = 0.04) and Oleic acid (p = 0.03). In conclusion, we are reporting that the exposure to sub lethal concentration of Imidacloprid disturb the muscle fatty acid composition of Labeo rohita that may affect its food quality. The effects were more pronounced under long term experimental conditions and were probably due to potentiating lipid peroxidation and disturbed fish metabolism upon Imidacloprid exposure.
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Cyprinidae , Neonicotinoides , Nitrocompostos , Praguicidas , Animais , Ácidos Graxos , Praguicidas/metabolismo , Músculos , Água Doce , Água/metabolismoRESUMO
Background Pre-liver transplant (LT) sarcopenia is associated with poor survival. Methods exist for measuring body composition with use of CT scans; however, it is unclear which components best predict post-LT outcomes. Purpose To quantify the association between abdominal CT-based body composition measurements and post-LT mortality in a large North American cohort. Materials and Methods This was a retrospective cohort of adult first-time deceased-donor LT recipients from 2009 to 2018 who underwent pre-LT abdominal CT scans, including at the L3 vertebral level, at Johns Hopkins Hospital. Measurements included sarcopenia (skeletal muscle index [SMI] <50 in men and <39 in women), sarcopenic obesity, myosteatosis (skeletal muscle CT attenuation <41 mean HU for body mass index [BMI] <25 and <33 mean HU for BMI ≥25), visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and VAT/SAT ratio. Covariates in the adjusted models were selected with use of least absolute shrinkage and selection operator regression with lambda chosen by means of 10-fold cross-validation. Cox proportional hazards models were used to quantify associations with post-LT mortality. Model discrimination was quantified using the Harrell C-statistic. Results A total of 454 recipients (median age, 57 years [IQR, 50-62 years]; 294 men) were evaluated. In the adjusted model, pre-LT sarcopenia was associated with a higher hazard ratio (HR) of post-LT mortality (HR, 1.6 [95% CI: 1.1, 2.4]; C-statistic, 0.64; P = .02). SMI was significantly negatively associated with survival after adjustment for covariates. There was no evidence that myosteatosis was associated with mortality (HR, 1.3 [95% CI: 0.86, 2.1]; C-statistic, 0.64; P = .21). There was no evidence that BMI (HR, 1.2 [95% CI: 0.95, 1.4]), VAT (HR, 1.0 [95% CI: 0.98, 1.1]), SAT (HR, 1.0 [95% CI: 0.97, 1.0]), and VAT/SAT ratio (HR, 1.1 [95% CI: 0.90, 1.4]) were associated with mortality (P = .15-.77). Conclusions Sarcopenia, as assessed on routine pre-liver transplant (LT) abdominal CT scans, was the only factor significantly associated with post-LT mortality. © RSNA, 2022 See also the editorial by Ruehm in this issue.
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Transplante de Fígado , Sarcopenia , Adulto , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Sarcopenia/complicações , Sarcopenia/diagnóstico por imagem , Estudos Retrospectivos , Doadores Vivos , Composição Corporal , Músculo Esquelético , Tomografia Computadorizada por Raios X/métodosRESUMO
BACKGROUND. Endovascular embolization of pulmonary arteriovenous malformations (PAVMs) was historically performed with embolic coils. The Amplatzer Vascular Plug device (AVP) was introduced for this purpose in 2007 and the Micro Vascular Plug device (MVP) in 2013. OBJECTIVE. The purpose of this study was to compare coils, AVPs, and MVPs in terms of risk of persistence after PAVM embolization by use of propensity score weighting to account for biases in device selection. METHODS. This retrospective study included 112 patients (78 women and girls, 34 men and boys; mean age, 45 years) who underwent embolization of 393 PAVMs with a single device type (coil, MVP, or AVP) from January 2003 to January 2020. Persistence was defined as less than 70% reduction in PAVM sac size or contrast enhancement of the sac on follow-up pulmonary CTA. A Cox proportional hazards regression model was used to assess associations between embolic device selection and PAVM persistence. Inverse propensity score weighting was used to account for differences in embolic device selection based on patient and PAVM characteristics. RESULTS. The median postembolization follow-up period was 1.5 years (IQR, 0.3-5.6 years). Persistence was found in 10% (41/393) of PAVMs, including 16% (34/207) of those treated with coils, 8% (7/88) of those treated with AVPs, and 0% (0/98) of those treated with MVPs. Variables associated with embolization device (p < .25) were age, sex, pediatric versus adult status, smoking status, PAVM complexity, PAVM laterality, number of feeding arteries, and feeding artery diameter. The Cox regression model incorporated inverse propensity score weighting to account for the differences between treatment groups in these variables and incorporated feeding artery diameter because of imbalance remaining after weighting. With coils as the referent, MVPs had a hazard ratio for persistence of less than 0.01 (95% CI, < 0.01 to < 0.01; p < .001), and AVPs had a hazard ratio of 0.37 (95% CI, 0.16-0.90; p = .03). CONCLUSION. The risk of persistence after PAVM embolization was significantly lower for MVPs alone than for coils or AVPs alone. In addition, the risk of persistence was lower for AVPs than for coils. CLINICAL IMPACT. The findings support the clinical use of MVPs as the preferred device for PAVM embolization over coils and polytetrafluoroethylene-covered plugs.
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Malformações Arteriovenosas , Embolização Terapêutica , Veias Pulmonares , Adulto , Masculino , Humanos , Feminino , Criança , Pessoa de Meia-Idade , Estudos Retrospectivos , Pontuação de Propensão , Resultado do Tratamento , Malformações Arteriovenosas/diagnóstico por imagem , Malformações Arteriovenosas/terapia , Artéria Pulmonar/diagnóstico por imagem , Artéria Pulmonar/anormalidades , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/anormalidades , Embolização Terapêutica/métodosRESUMO
BACKGROUNDS: Acne vulgaris is a chronic inflammatory skin disease of the pilosebaceous unit affecting most teenagers and numerous adults throughout the world. The present study was designed to assess the association of the presence or absence of GSTM1, GSTT1, and single nucleotide polymorphisms rs1695 in GSTP1 and rs1042522 in TP53 gene with acne vulgaris. METHODS: The cross-sectional case-control study was conducted at the Institute of Zoology from May 2020 to March 2021 and included acne vulgaris patients (N = 100) and controls (N = 100) enrolled in Dera Ghazi Khan district, Pakistan. Multiplex and tetra-primer amplification refractory mutation system-polymerase chain reactions were applied to investigate the genotype in analyzed genes. The association of rs1695 and rs1042522 with acne vulgaris was studied either individually or in various combinations with GATM1 and T1. RESULTS: A significant association of absence of GSTT1 and mutant genotype at rs1695 (GG) and at rs1042522 (CC) in GSTP1 and TP53, respectively, was found to be associated with acne vulgaris in enrolled subjects. Subjects aged 10-25 years and smokers were more susceptible to acne vulgaris. CONCLUSION: Our results suggest that genotypes of glutathione S-transferases (GSTs) and TP53 are involved in protection against oxidative stress and may influence disease progression in acne vulgaris.
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Acne Vulgar , Predisposição Genética para Doença , Adulto , Adolescente , Humanos , Incidência , Estudos de Casos e Controles , Estudos Transversais , Predisposição Genética para Doença/genética , Fatores de Risco , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Acne Vulgar/epidemiologia , Acne Vulgar/genética , Proteína Supressora de Tumor p53/genética , Glutationa S-Transferase pi/genéticaRESUMO
Type II diabetes mellitus and its related complications are growing public health problems. Many natural products present in our diet, including polyphenols, can be used in treating and managing type II diabetes mellitus and different diseases, owing to their numerous biological properties. Anthocyanins, flavonols, stilbenes, curcuminoids, hesperidin, hesperetin, naringenin, and phenolic acids are common polyphenols found in blueberries, chokeberries, sea-buckthorn, mulberries, turmeric, citrus fruits, and cereals. These compounds exhibit antidiabetic effects through different pathways. Accordingly, this review presents an overview of the most recent developments in using food polyphenols for managing and treating type II diabetes mellitus, along with various mechanisms. In addition, the present work summarizes the literature about the anti-diabetic effect of food polyphenols and evaluates their potential as complementary or alternative medicines to treat type II diabetes mellitus. Results obtained from this survey show that anthocyanins, flavonols, stilbenes, curcuminoids, and phenolic acids can manage diabetes mellitus by protecting pancreatic ß-cells against glucose toxicity, promoting ß-cell proliferation, reducing ß-cell apoptosis, and inhibiting α-glucosidases or α-amylase. In addition, these phenolic compounds exhibit antioxidant anti-inflammatory activities, modulate carbohydrate and lipid metabolism, optimize oxidative stress, reduce insulin resistance, and stimulate the pancreas to secrete insulin. They also activate insulin signaling and inhibit digestive enzymes, regulate intestinal microbiota, improve adipose tissue metabolism, inhibit glucose absorption, and inhibit the formation of advanced glycation end products. However, insufficient data are available on the effective mechanisms necessary to manage diabetes.
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Diabetes Mellitus Tipo 2 , Estilbenos , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Antocianinas/farmacologia , Hipoglicemiantes/farmacologia , Hipoglicemiantes/uso terapêutico , Glucose/metabolismo , Insulina/metabolismo , Antioxidantes/farmacologia , Flavonóis , Diarileptanoides/uso terapêutico , Estilbenos/uso terapêuticoRESUMO
Fruits, vegetables, and other food items contain phytochemicals or secondary metabolites which may be considered non-essential nutrients but have medicinal importance. These dietary phytochemicals exhibit chemopreventive and therapeutic effects against numerous diseases. Polyphenols are secondary metabolites found in vegetables, fruits, and grains. These compounds exhibit several health benefits such as immune modulators, vasodilators, and antioxidants. This review focuses on recent studies on using dietary polyphenols to treat cardiovascular disorders, atherosclerosis, and vascular endothelium deficits. We focus on exploring the safety of highly effective polyphenols to ensure their maximum impact on cardiac abnormalities and discuss recent epidemiological evidence and intervention trials related to these properties. Kaempferol, quercetin, and resveratrol prevent oxidative stress by regulating proteins that induce oxidation in heart tissues. In addition, polyphenols modulate the tone of the endothelium of vessels by releasing nitric oxide (NO) and reducing low-density lipoprotein (LDL) oxidation to prevent atherosclerosis. In cardiomyocytes, polyphenols suppress the expression of inflammatory markers and inhibit the production of inflammation markers to exert an anti-inflammatory response. Consequently, heart diseases such as strokes, hypertension, heart failure, and ischemic heart disease could be prevented by dietary polyphenols.
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Aterosclerose , Insuficiência Cardíaca , Polifenóis/farmacologia , Polifenóis/uso terapêutico , Verduras , Endotélio VascularRESUMO
The present study was designed to evaluate the in vitro and in silico potential of the Schiff bases (Z)-4-ethoxy-N-((5-nitrothiophen-2-yl)methylene)benzenamine (1) and (Z)-2,4-diiodo-6-((2-methyl-3-nitrophenylimino)methyl)phenol (2). These Schiff bases were synthesized according to a reported method using ethanol as a solvent, and each reaction was monitored on a TLC until completion of the reaction. The structures of both compounds were elucidated using spectroscopic techniques such as UV-Vis, FTIR, 1H NMR and 13C NMR. Molecular structure was determined using single-crystal XRD, which revealed that compounds 1 and 2 were monoclinic and triclinic, respectively. Hirshfeld surface analysis (HS) and 2D fingerprint plots were used to determine the intermolecular interactions along the contact contribution in the crystalline molecules. The structures of both compounds were optimized through a hybrid functional method B3LYP using the 6-31G(d,p) basis set, and various structural parameters were studied. The experimental and theoretical parameters (bond angle and bond length) of the compounds were compared with each other and are in close agreement. The in vitro esterase potential of the synthesized compounds was checked using a spectrophotometric model, while in silico molecular docking studies were performed with AutoDock against two enzymes of the esterase family. The docking studies and the in vitro assessment predicted that such molecules could be used as enzyme inhibitors against the tested enzymes: acetylcholine esterase (AChE) and butyrylcholine esterase (BChE).
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Inibidores Enzimáticos , Bases de Schiff , Simulação de Acoplamento Molecular , Cristalografia por Raios X , Bases de Schiff/química , Espectroscopia de Ressonância Magnética , EsterasesRESUMO
BACKGROUND: Suicide is a social relevant issue and a leading cause of deaths in the world; it has been reported that COVID-19 has significantly increased the rate of suicide worldwide. This study aimed to review media reporting on suicide cases occurred in Pakistan during the COVID-19 lockdown. SUBJECTS AND METHODS: A content analysis has been performed considering the electronic version of the daily Kawish newspaper reporting suicide cases from March to August 2020 in Pakistan. RESULTS: A total of 213 news regarding suicide in Pakistan during the lockdown period were identified. Suicide committers reported age ranging 19-30 years old, and the majority of them were males (74%). Suicide methods ranged as following: harmful practices (79%) > hanging (37%) > self-poisoning (28%). Factors associated to the risk of suicide were: familial discords (36%), poverty (21%) and joblessness (14%). CONCLUSION: Findings of this study have shown that pandemic lockdown in Pakistan have increased the number of factors, such as family issues, unemployment and poverty, leading to suicide especially in young males. The report of suicides may have an impact on the public general opinion and a responsible news-reporting is needed by press agencies and media.
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COVID-19 , Suicídio , Adulto , Feminino , Humanos , Masculino , Adulto Jovem , Controle de Doenças Transmissíveis , Paquistão/epidemiologia , Opinião PúblicaRESUMO
Background: This study was aimed to observe newspaper reports about non-fatal suicide attempts in Pakistan during the COVID-19 lockdown. Methods: We performed content analysis of news reports about incomplete suicides from four vernacular newspapers of Pakistan between March and August 2020. Results: A total of 87 news reports about suicide attempts were examined; the vast majority of the suicide attempters was Muslims (78%), males (64%), females (36%) with (33%) mentions of age, ranging from 19-30 years, and married were (76%). However, occupation was largely missing from (93%) of the news. Self-poisoning was the commonly reported method in (65%) of suicide attempts, whereas familial discord was the leading risk factor for (72%) of suicide attempts. Conclusions: Although psychological intervention is crucial to reduce familial discords as risk factors, monitoring the mental health conditions of people vulnerable to suicide and the figures on attempted suicides should be maintained and collected nationally and regionally.
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Though considerable research has been reported on COVID-19-related distance education, some dimensions of remote foreign language teaching experiences during the pandemic crisis remain to be explored. The study reported in this paper investigated Saudi university foreign language teachers' accumulated experiences and reflective beliefs of emergency remote instruction. The study focused specifically on: a) the general educational challenges the teachers encountered and their attempts to overcome them; b) the teachers' perceived difficulties in remotely teaching and assessing foreign language areas and their strategies for coping with them; and c) their reflective evaluation of remote foreign language teaching after doing it for three academic terms. Questionnaire data was collected from 112 teachers of Arabic and English as foreign languages, and semi-structured interviews were conducted with 14 teachers. The analysis of both data types showed that the participants had a number of general educational and language-teaching-specific challenges in their COVID-19-related remote teaching. The teachers generally viewed the remote assessment of language areas is a more challenging task than teaching them. Reading was rated as the least difficult language area to teach and assess remotely, whereas writing was the most difficult one. The teachers reported using various coping strategies to overcome the educational and language teaching-specific challenges. They perceived their remote teaching experiences positively, but reported their needs for further training in developing better online assessment methods, using different teaching platforms and technological tools, and managing classroom interactions. The paper ends by discussing the results of the study and their implications.
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OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) can persist in the stage of simple hepatic steatosis or progress to steatohepatitis (NASH) with an increased risk for cirrhosis and cancer. We examined the mechanisms controlling the progression to severe NASH in order to develop future treatment strategies for this disease. DESIGN: NFATc1 activation and regulation was examined in livers from patients with NAFLD, cultured and primary hepatocytes and in transgenic mice with differential hepatocyte-specific expression of the transcription factor (Alb-cre, NFATc1c.a . and NFATc1Δ/Δ ). Animals were fed with high-fat western diet (WD) alone or in combination with tauroursodeoxycholic acid (TUDCA), a candidate drug for NAFLD treatment. NFATc1-dependent ER stress-responses, NLRP3 inflammasome activation and disease progression were assessed both in vitro and in vivo. RESULTS: NFATc1 expression was weak in healthy livers but strongly induced in advanced NAFLD stages, where it correlates with liver enzyme values as well as hepatic inflammation and fibrosis. Moreover, high-fat WD increased NFATc1 expression, nuclear localisation and activation to promote NAFLD progression, whereas hepatocyte-specific depletion of the transcription factor can prevent mice from disease acceleration. Mechanistically, NFATc1 drives liver cell damage and inflammation through ER stress sensing and activation of the PERK-CHOP unfolded protein response (UPR). Finally, NFATc1-induced disease progression towards NASH can be blocked by TUDCA administration. CONCLUSION: NFATc1 stimulates NAFLD progression through chronic ER stress sensing and subsequent activation of terminal UPR signalling in hepatocytes. Interfering with ER stress-responses, for example, by TUDCA, protects fatty livers from progression towards manifest NASH.
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Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/metabolismo , Fígado/metabolismo , Hepatócitos/metabolismo , Fatores de Transcrição/metabolismo , Inflamação/metabolismo , Camundongos Transgênicos , Progressão da Doença , Camundongos Endogâmicos C57BL , Fatores de Transcrição NFATC/metabolismoRESUMO
Genetic counseling is an important means of identifying a patient's genetic risk of hereditary hemorrhagic telangiectasia (HHT) and assisting patients in making informed decisions about their health. With an increase in understanding of the genetic mechanisms underlying HHT over the last decade, genetic counseling is increasingly being incorporated into the care of patients affected by HHT. In addition to refining the diagnosis of symptomatic patients, genetic testing can help to distinguish asymptomatic, at-risk patients from those who are unaffected by HHT. The purpose of this review article is to summarize the current knowledge regarding the role of genetic counseling and genetic testing in identifying and managing HHT in at-risk populations. This article also reviews the guidelines, outcomes, risks, and challenges of genetic counseling and testing for HHT in various patient populations, and provides an algorithm for the use of genetic counseling in symptomatic and asymptomatic patients.
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Telangiectasia Hemorrágica Hereditária , Aconselhamento Genético , Testes Genéticos , Humanos , Fatores de Risco , Telangiectasia Hemorrágica Hereditária/diagnóstico , Telangiectasia Hemorrágica Hereditária/genéticaRESUMO
Mitochondrial protein synthesis requires three elongation factors including EF-Tu (TUFM; OMIM 602389), EF-Ts (TSFM; OMIM 604723), and EF-G1 (GFM1; OMIM 606639). Pathogenic variants in any of these three members result in defective mitochondrial translation which can impart an oxidative phosphorylation (OXPHOS) deficiency. In this study, we investigated a consanguineous Pakhtun Pakistani family. There were four affected siblings at the time of this study and one affected girl had died in infancy. The index patient had severe intellectual disability, global developmental delay, dystonia, no speech development, feeding difficulties, and nystagmus. MRI brain presented thinning of corpus callosum and polymicrogyria. Whole exome sequencing revealed a novel compound heterozygous variant in GFM1 located on chromosome 3q25.32. Sanger sequencing confirmed recessive segregation of the maternal (NM_001308164.1:c.409G > A; p.Val137Met) and paternal (NM_001308164.1:c.1880G > A; p.Arg627Gln) variants in all the four affected siblings. These variants are classified as "likely-pathogenic" according to the recommendation of ACMG/AMP guideline. GFM1 alterations mostly lead to severe phenotypes and the patients may die in early neonatal life; however, four of the affected siblings had survived till the ages of 10-17 years, without developing any life-threatening conditions. Mostly, in cousin marriages, the pathogenic variants are identical-by-descent, and affected siblings born to such parents are homozygous. Three homozygous variants were shortlisted in the analysis of the WES data, but Sanger sequencing did not confirm their segregation with the disease phenotype. This is the first report from Pakistan expanding pathogenicity of GFM1 gene.
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Distonia , Distúrbios Distônicos , Deficiência Intelectual , Polimicrogiria , Distonia/genética , Exoma/genética , Humanos , Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Proteínas Mitocondriais/genética , Mutação , Linhagem , Fator G para Elongação de Peptídeos/genética , Fatores de Alongamento de Peptídeos/genética , Polimicrogiria/genética , Sequenciamento do ExomaRESUMO
An autonomous driving environment poses a very stringent requirement for the timely delivery of safety messages in vehicular ad hoc networks (VANETs). Time division multiple access (TDMA)-based medium access control (MAC) protocols are considered a promising solution because of their time-bound message delivery. However, in the event of mobility-caused packet collisions, they may experience an unpredicted and extended delay in delivering messages, which can cause catastrophic accidents. To solve this problem, a distributed TDMA-based MAC protocol with mobility-caused collision mitigation (MCCM-MAC) is presented in this paper. The protocol uses a novel mechanism to detect merging collisions and mitigates them by avoiding subsequent access collisions. One vehicle in the merging collisions retains the time slot, and the others release the slot. The common neighboring vehicles can timely suggest a suitable new time slot for the vacating vehicles, which can avoid access collisions between their packet transmissions. A tie-breakup mechanism is employed to avoid further access collisions. Simulation results show that the proposed protocol reduces packet loss more than the existing methods. Consequently, the average delay between the successfully delivered periodic messages is also reduced.
RESUMO
Rheumatoid arthritis is primarily associated with inflammation and increased level of proinflammatory cytokines which are released by immune cells, macrophages or activation of arachidonic acid metabolism. The expression of these cytokines, oxidative free radicals and the activation of COX-2 enzymes are crucial targets for chronic inflammation. On the basis of established anti-inflammatory efficacy of nerolidol, the primary study was further appraised to determine its approach against Freund's complete adjuvant (CFA) rheumatoid model. Arthritis was induced by inoculation of 0.1 mL CFA injection into the left hind footpad of rats. Anti-arthritic potential of nerolidol (at 200, 400 and 800 mg/kg doses) was assessed by measuring the paw volume, body weight, serum analysis, histopathological and radiographs of ankle joints. Expressions of cytokine's panels such as IL-10, IL-4, COX-2, NF-kB, TNF-α, IL-6, PGE-2 and IL-1ß were determined by real-time qPCR. Antioxidant enzyme analyses were conducted by measuring the SOD, POD and catalase activity from serum and equated with arthritic control group. Nerolidol prevented body weight loss, stabilized biochemical and haematological homeostasis and significantly reduced the paw volume. Furthermore, X-ray and histopathological assessment of ankle joints showed an improvement in the joint structure of rats treated with nerolidol. Besides that, overexpression of gene pointers like TNF-α, IL-1ß, IL-6, NF-kB, PGE-2 and COX-2 in CFA-treated control rats were also reversed with nerolidol. This anti-arthritic mechanism was further supported by the increased level of IL-10, IL-4 and serum antioxidant activity. The present findings demonstrate that nerolidol reduced adjuvant arthritis by downregulating the proinflammatory cytokines and upregulating the aforementioned anti-inflammatory cytokines and may be used as a therapeutic substance for the management of human rheumatoid arthritis.