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In this study, we have demonstrated, for the first time, the muscular protective effects of Piranhea trifoliata bark extract against Paraquat (PQ)-induced oxidative stress in Drosophila melanogaster. Exposure of D. melanogaster (Canton Special) to PQ caused oxidative stress, as evidenced by protein carbonyl and elevated acetylcholinesterase (AChE) activity levels. However, a diet supplemented with the P. trifoliata extracts (0.1 mg/ml) for 10 days ameliorates protein carbonyl levels and enzymatic activities of AChE and citrate synthase to prevent PQ damage. Also, P. trifoliata bark extracts showed in phytochemical assays the presence of phenols, at 46.06 mg EAG/g extract of total phenolic compounds, and a 40% 2,2-diphenyl-1-picryl-hydrazyl scavenging effect. The study showed the muscular protective function of the P. trifoliata extracts in D. melanogaster exposed to PQ. On the basis of the results, we contemplate that the bark of P. trifoliata might prevent and ameliorate human diseases caused by oxidative stress. The muscular action of the P. trifoliata extract can be attributed to the antioxidant constituents, while the precise mechanism of its action needs further investigation.
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Drosophila melanogaster , Paraquat , Animais , Humanos , Paraquat/toxicidade , Acetilcolinesterase/metabolismo , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Estresse Oxidativo , Extratos Vegetais/farmacologia , Extratos Vegetais/metabolismo , Fenóis/metabolismo , Fenóis/farmacologiaRESUMO
Macrophages are tissue-resident immune cells that are crucial for the initiation and maintenance of immune responses. Purinergic signaling modulates macrophage activity and impacts cellular plasticity. The ATP-activated purinergic receptor P2X7 (also known as P2RX7) has pro-inflammatory properties, which contribute to macrophage activation. P2X7 receptor signaling is, in turn, modulated by ectonucleotidases, such as CD39 (also known as ENTPD1), expressed in caveolae and lipid rafts. Here, we examined P2X7 receptor activity and determined impacts on ectonucleotidase localization and function in macrophages primed with lipopolysaccharide (LPS). First, we verified that ATP boosts CD39 activity and caveolin-1 protein expression in LPS-primed macrophages. Drugs that disrupt cholesterol-enriched domains - such as nystatin and methyl-ß-cyclodextrin - decreased CD39 enzymatic activity in all circumstances. We noted that CD39 colocalized with lipid raft markers (flotillin-2 and caveolin-1) in macrophages that had been primed with LPS followed by treatment with ATP. P2X7 receptor inhibition blocked these ATP-mediated increases in caveolin-1 expression and inhibited the colocalization with CD39. Further, we found that STAT3 activation is significantly attenuated caveolin-1-deficient macrophages treated with LPS or LPS+BzATP. Taken together, our data suggest that P2X7 receptor triggers the initiation of lipid raft-dependent mechanisms that upregulates CD39 activity and could contribute to limit macrophage responses restoring homeostasis.
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Caveolina 1 , Receptores Purinérgicos P2X7 , Trifosfato de Adenosina , Caveolina 1/genética , Lipopolissacarídeos , Macrófagos , Microdomínios da Membrana , Receptores Purinérgicos P2X7/genéticaRESUMO
Next-generation sequencing (NGS) increasingly influences diagnosis, prognosis and management of myelodysplastic syndrome (MDS). In addition to marrow morphology and flow cytometry, our institution performs cytogenetics (CG) and NGS-based testing routinely in patients with suspected MDS. We evaluated the relative value of NGS in the assessment of patients with suspected MDS. We initially compared the diagnostic and prognostic information derived from CG and NGS in 134 patients. NGS enhanced the diagnostic yield compared to CG for clonal myeloid disorders (sensitivity 77% vs. 42·2%; specificity 90·2% vs. 78%; positive predictive value 92·8% vs. 76%; and negative predictive value 70·8% vs. 45·5%). The identification of poor prognosis mutations by NGS altered risk category in 27/39 (69·2%) patients with MDS with good/intermediate risk CG. Subsequently, we prospectively evaluated 70 patients with suspected MDS using an 'NGS-first approach' with CG restricted to samples with morphological abnormalities. We rarely identified mutations or CG abnormalities in patients without dysplastic features. NGS has a superior diagnostic performance compared to CG in patients with suspected MDS. We estimate that by using an 'NGS-first approach' we could reduce karyotyping by approximately 30%.
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Análise Citogenética , Sequenciamento de Nucleotídeos em Larga Escala , Síndromes Mielodisplásicas/genética , Aberrações Cromossômicas , Humanos , Mutação , Síndromes Mielodisplásicas/diagnóstico , Prognóstico , Estudos RetrospectivosRESUMO
The study was conducted to evaluate the frequency of polymorphisms in GSTM1 and GSTT1 genes in patients with breast cancer compared with individuals without history of cancer, and the association of these polymorphisms with clinical/epidemiological parameters.There were evaluated 752 women (219 patients and 533 controls). Molecular analysis was performed by the Polymerase Chain Reaction (PCR). Statistical analysis was used multiple logistic regression and descriptive statistics.Age ≥ 50 years (OR = 3.22, 95% CI = 2.30-4.51, p < 0.001) and alcohol consumption (OR = 1.60, 95% CI = 1.13-2.27, p = 0.008) were associated to the development of breast cancer, while smoking and null genotypes GSTM1 and GSTT1 presented no association. GSTM1 and GSTT1 polymorphisms presented no relationship with the clinical and histopathological parameters or molecular subtypes of breast cancer. Ninety-two percent of tumours were invasive ductal, 66% were grade II, 65% were larger than 2 cm, the stages II (35.3%) and III (31.2%) were the most prevalent, and 47.7% were molecular subtype luminal B.Individuals aged ≥ 50 years and alcohol consumers have more chance to developing breast cancer. GSTM1 and GSTT1 polymorphisms are not associated to the risk of breast cancer.
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Neoplasias da Mama , Glutationa Transferase , Neoplasias da Mama/genética , Estudos de Casos e Controles , Feminino , Genótipo , Glutationa Transferase/genética , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Polimorfismo GenéticoRESUMO
We investigated the association between methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthetase (MTR A2756G), and methionine synthase reductase (MTRR A66G) polymorphisms involved in folate pathway and breast cancer risk, and the interaction between these polymorphisms and tobacco and alcohol consumption. Furthermore, we evaluated the association between these polymorphisms and clinicopathological variables. This case-control study included 606 Brazilian women, comprising 128 patients with breast cancer and 478 controls. MTHFR and MTR polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and MTRR polymorphisms using real-time PCR. Age ≥50 years (odds ratio [OR]: 2.65; 95% confidence interval [CI]: 1.65-4.26; p<0.001) and alcohol consumption (OR: 1.76; 95% CI: 1.0-2.85; p=0.021) were associated with an increased risk of breast cancer. For MTHFR A1298C, we observed a reduced risk of developing breast cancer in the codominant model (genotype CC-OR: 0.22; 95% CI: 0.06-0.74; p=0.014), recessive model (OR: 0.22; 95% CI: 0.07-0.76 p=0.004), and log-additive model (OR: 0.70; 95% CI: 0.49-0.98; p=0.035). Women aged ≥50 years and those who are alcohol consumers had increased susceptibility to breast cancer, and MTHFR A1298C modulated the risk for this disease. This is the first study to evaluate the association between polymorphisms in folate metabolism and breast cancer in the northwest region of São Paulo State, Brazil.
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INTRODUCTION: Food allergy is considered a public health problem for children. The modulation of the intestinal microbiota seems a promising strategy for the control of allergic reactions. OBJECTIVE: To describe the effects of different forms of probiotics in pediatric food hypersensitivity treatment. DATA SOURCE: We conducted a systematic review based on clinical trials published in the PubMed and Web of Science databases. The searches were carried out using the MeSH terms "Food Hypersensitivity," "Probiotics," "Lactobacillus," and "Bifidobacterium". DATA SYNTHESIS: The final selection resulted in 18 clinical trials, which were predominantly samples of infants and pre-school children. The most-often used strain, either alone or in combination, was Lactobacillus rhamnosus GG; a placebo was mainly used in the control group. As for the vehicle, the most common forms were capsules and infant formulas, and the period of intervention ranged from four weeks to 24 months, with weekly or monthly visits to measure the outcomes. In these 18 trials, 46 analyses were performed with 27 different types of outcomes to evaluate the effects of probiotics (12 laboratory and 15 clinical). Twenty-seven of these analyses demonstrated the benefits of using these microorganisms. The SCORAD (atopic dermatitis index) and IgE levels and cytokines were the outcomes mostly evaluated. CONCLUSION: The use of probiotics is beneficial in promoting immunomodulation and reducing clinical symptoms. However, more methodologically based research is needed to clarify the effect from each type, dose, and time of using them for the establishment of definitive care protocols.
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Hipersensibilidade Alimentar/tratamento farmacológico , Probióticos/uso terapêutico , Bifidobacterium/classificação , Criança , Ensaios Clínicos como Assunto , Hipersensibilidade Alimentar/prevenção & controle , Humanos , Imunomodulação , Lactobacillus/classificação , Resultado do TratamentoRESUMO
Psd1 is a pea plant defensin which can be actively expressed in Pichia pastoris and shows broad antifungal activity. This activity is dependent on fungal membrane glucosylceramide (GlcCer), which is also important for its internalization, nuclear localization, and endoreduplication. Certain cancer cells present a lipid metabolism imbalance resulting in the overexpression of GlcCer in their membrane. In this work, in vitroassays using B16F10 cells showed that labeled fluorescein isothiocyanate FITC-Psd1 internalized into live cultured cells and targeted the nucleus, which underwent fragmentation, exhibiting approximately 60% of cells in the sub-G0/G1 stage. This phenomenon was dependent on GlcCer, and the participation of cyclin-F was suggested. In a murine lung metastatic melanoma model, intravenous injection of Psd1 together with B16F10 cells drastically reduced the number of nodules at concentrations above 0.5 mg/kg. Additionally, the administration of 1 mg/kg Psd1 decreased the number of lung inflammatory cells to near zero without weight loss, unlike animals that received melanoma cells only. It is worth noting that 1 mg/kg Psd1 alone did not provoke inflammation in lung tissue or weight or vital signal losses over 21 days, inferring no whole animal cytotoxicity. These results suggest that Psd1 could be a promising prototype for human lung anti-metastatic melanoma therapy.
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Antineoplásicos Fitogênicos/farmacologia , Defensinas/farmacologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/secundário , Pisum sativum/química , Proteínas de Plantas/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Apoptose/efeitos dos fármacos , Biópsia , Linhagem Celular , Permeabilidade da Membrana Celular , Proliferação de Células/efeitos dos fármacos , Defensinas/química , Modelos Animais de Doenças , Feminino , Imunofluorescência , Glucosilceramidas/metabolismo , Imuno-Histoquímica , Neoplasias Pulmonares/tratamento farmacológico , Melanoma Experimental , Camundongos , Modelos Moleculares , Proteínas de Plantas/química , Conformação Proteica , Relação Estrutura-AtividadeRESUMO
Despite advances in the treatment of HIV infection with ART, elucidating strategies to overcome HIV persistence, including blockade of viral reservoir establishment, maintenance, and expansion, remains a challenge. T cell homeostasis is a major driver of HIV persistence. Cytokines involved in regulating homeostasis of memory T cells, the major hub of the HIV reservoir, trigger the Jak-STAT pathway. We evaluated the ability of tofacitinib and ruxolitinib, two FDA-approved Jak inhibitors, to block seeding and maintenance of the HIV reservoir in vitro. We provide direct demonstration for involvement of the Jak-STAT pathway in HIV persistence in vivo, ex vivo, and in vitro; pSTAT5 strongly correlates with increased levels of integrated viral DNA in vivo, and in vitro Jak inhibitors reduce the frequency of CD4+ T cells harboring integrated HIV DNA. We show that Jak inhibitors block viral production from infected cells, inhibit γ-C receptor cytokine (IL-15)-induced viral reactivation from latent stores thereby preventing transmission of infectious particles to bystander activated T cells. These results show that dysregulation of the Jak-STAT pathway is associated with viral persistence in vivo, and that Jak inhibitors target key events downstream of γ-C cytokine (IL-2, IL-7 and IL-15) ligation to their receptors, impacting the magnitude of the HIV reservoir in all memory CD4 T cell subsets in vitro and ex vivo. Jak inhibitors represent a therapeutic modality to prevent key events of T cell activation that regulate HIV persistence and together, specific, potent blockade of these events may be integrated to future curative strategies.
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Fármacos Anti-HIV/farmacologia , Linfócitos T CD4-Positivos/virologia , Infecções por HIV/virologia , Inibidores de Janus Quinases/farmacologia , Latência Viral/efeitos dos fármacos , Linfócitos T CD4-Positivos/efeitos dos fármacos , Células Cultivadas , HIV-1/efeitos dos fármacos , HIV-1/fisiologia , Humanos , Nitrilas , Piperidinas/farmacologia , Pirazóis/farmacologia , Pirimidinas/farmacologia , Pirróis/farmacologia , Replicação Viral/efeitos dos fármacosRESUMO
OBJECTIVES: The diagnosis of hematologic malignancies integrates multiple diagnostic and clinical disciplines. Historically, targeted (single-analyte) genetic testing has been used as reflex to initial prescreening by other diagnostic modalities including flow cytometry, anatomic pathology, and clinical cytogenetics. Given the wide range of mutations associated with hematologic malignancies a DNA/RNA-based NGS panel can provide a more effective and economical approach to comprehensive testing of patients as an initial, tier-1 screen. METHODS: Using a cohort of 380 patients, we performed clinical validation of a gene panel designed to assess 40 genes (DNA), and 29 fusion driver genes with over 600 gene fusion partners (RNA), including sample exchange data across three clinical laboratories, and correlation with cytogenetic testing results. RESULTS: The clinical validation of this technology demonstrated that its accuracy, sensitivity, and specificity are comparable to the majority of targeted single-gene approaches, while assessment of the initial patient cohort data demonstrated a high diagnostic yield of 50.5%. CONCLUSIONS: Implementation of a tier-1 NGS-based protocol for gene panel screening provides a comprehensive alternative to targeted molecular testing in patients with suspected hematologic malignancies, with increased diagnostic yield, scalability, reproducibility, and cost effectiveness, making it ideally suited for implementation in clinical laboratories.
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Biomarcadores Tumorais , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/genética , Sequenciamento de Nucleotídeos em Larga Escala , Proteínas de Fusão Oncogênica/genética , Biologia Computacional/métodos , Predisposição Genética para Doença , Testes Genéticos , Variação Genética , Genômica/métodos , Neoplasias Hematológicas/epidemiologia , Humanos , Mutação , Estudos RetrospectivosRESUMO
We designed and conducted a series of primordial-soup Miller-Urey style experiments with deuterated gases and reagents to compare the spark-discharge products of a "deuterated world" with the standard reaction in the "hydrogenated world". While the deuteration of the system has little effect on the distribution of amino acid products, significant differences are seen in other regions of the product-space. Not only do we observe about 120â new species, we also see significant differences in their distribution if the two hydrogen isotope worlds are compared. Several isotopologue matches can be identified in both, but a large proportion of products have no equivalent in the corresponding isotope world with ca. 43â new species in the D world and ca. 39â new species in the H world. This shows that isotopic exchange (the addition of only one neutron) may lead to significant additional complexity in chemical space under otherwise identical reaction conditions.
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Infecções por Coronavirus/diagnóstico , Síndrome do Intestino Irritável/diagnóstico , Pneumonia Viral/diagnóstico , Betacoronavirus , COVID-19 , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/terapia , Colite Ulcerativa/virologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Humanos , Síndrome do Intestino Irritável/terapia , Síndrome do Intestino Irritável/virologia , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Síndrome do Desconforto Respiratório , SARS-CoV-2RESUMO
Improved access to water is a key factor in reducing diarrhoeal diseases, a leading cause of death among children in sub-Saharan Africa. In terms of water access, sub-Saharan African cities are some of the worst off in the world, with 20% of populations supplied by an unimproved water source. This situation is even worse in informal settlement areas. Using cross-sectional data on access to water from a survey implemented in three informal neighbourhoods of the Ouagadougou Health and Demographic Surveillance System, logistic regressions are modelled to test the effect of different modalities of access to water on childhood diarrhoea. Our results show that the prevalence of diarrhoea in children is high: one-third of households with a child under 10 experienced an episode of childhood diarrhoea during the 2 weeks preceding the survey, even though 91% of the households surveyed have access to an improved water source. The results show that efforts to reduce childhood morbidity would be greatly enhanced by strengthening piped water access in informal settlement areas in Africa. In addition, this study confirms that, beyond the single measure of the main access to water, accurate variables that assess the accessibility to water are needed.
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Diarreia/etiologia , Microbiologia da Água , Abastecimento de Água , Burkina Faso , Criança , Estudos Transversais , Diarreia/epidemiologia , Habitação , Humanos , Fatores de RiscoRESUMO
Using data on 825 under-5 children from the Ouagadougou Health and Demographic Surveillance System collected in 2010, this article examines the effects of aspects of the immediate environment on childhood fever. Logit regression models were estimated to assess the effects of the quality of the local environment on the probability that a child is reported to have had a fever in the two weeks preceding the survey, after controlling for various demographic and socioeconomic variables. While the estimated impact of some environmental factors persisted in the full models, the effects of variables such as access to water and type of household waste management decreased in the presence of demographic, socioeconomic and neighbourhood factors. The management of waste water was found to significantly affect the occurrence of childhood fever. Overall, the results of the study call for more efforts to promote access to tap water to households at prices that are affordable for the local population, where the threats to child health appears to be greatest.
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Saúde da Criança , Meio Ambiente , Febre/epidemiologia , Febre/etiologia , Fatores Socioeconômicos , Burkina Faso/epidemiologia , Criança , Pré-Escolar , Demografia , Saúde Ambiental , Características da Família , Feminino , Humanos , Modelos Logísticos , Masculino , Fatores de Risco , Águas ResiduáriasRESUMO
Connexins are essential gap junction proteins that play pivotal roles in intercellular communication in various organs of mammals. Connexin-43 (Cx43) is expressed in various components of the immune system, and there is extensive evidence of its participation in inflammation responses. The involvement of Cx43 in macrophage functionality involves the purinergic signaling pathway. Macrophages contribute to defenses against inflammatory reactions such as bacterial sepsis and peritonitis. Several assays can identify the presence and activity of Cx43 in macrophages. Real-time polymerase chain reaction (PCR) can measure the relative mRNA expression of Cx43, whereas western blotting can detect protein expression levels. Using immunofluorescence assays, it is possible to analyze the expression and observe the localization of Cx43 in cells or tissues. Moreover, connexin-mediated gap junction intercellular communication can be evaluated using functional assays such as microinjection of fluorescent dyes or scrape loading-dye transfer. The use of selective inhibitors contributes to this understanding and reinforces the role of connexins in various processes. Here, we discuss these methods to evaluate Cx43 and macrophage gap junctions.
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Conexina 43 , Junções Comunicantes , Macrófagos , Animais , Humanos , Western Blotting , Comunicação Celular , Conexina 43/análise , Conexina 43/genética , Conexina 43/metabolismo , Imunofluorescência , Junções Comunicantes/metabolismo , Macrófagos/metabolismo , Macrófagos/imunologia , Reação em Cadeia da Polimerase em Tempo Real , RNA Mensageiro/genética , RNA Mensageiro/metabolismoRESUMO
INTRODUCTION: The lack of human resources for disease prevention and control is evident in times of health crisis, such as the COVID-19 pandemic. In public health emergencies, the capacity for adequate assistance and guaranteed access to pharmacological treatment are fundamental and contribute to impact reduction. We aimed to analyze the profile, performance, and characteristics related to the self-perception of preparedness among pharmacists who responded to the COVID-19 pandemic in Brazil. METHOD: A cross-sectional study was conducted in two stages: content validation of a questionnaire and its application to a representative sample of pharmacists in Rio de Janeiro. The snowball technique was used to recruit participants. A logistic regression model was adjusted to determine the effects of the factors on the probability of a pharmacist feeling prepared to act during the pandemic. RESULTS: Six experts approved and validated the questionnaire, and 376 pharmacists were included in the study, 60.6 % of whom were in places specially designated by health authorities to diagnose and treat COVID-19. Professionals participated in various activities related to pandemic demands, including medication management and population guidance. Postgraduate degrees increased the odds of participants feeling prepared to act during the pandemic. Furthermore, pharmacists who worked in reference facilities were more likely to feel ready than those who worked in other places. Professionals who knew treatment guidelines were almost three times more likely to feel prepared than the ones without the knowledge of treatment guidelines. Training or guidance on how to act during the pandemic increased pharmacists' odds of feeling prepared by 2.58 times. CONCLUSION: Pharmacists actuated from diagnosis to treatment and participated in the health activities required during the pandemic. Factors contributing to the self-perception of preparedness were identified. Such factors can be targets for interventions to promote the preparedness of the workforce for future health emergencies.
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COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/terapia , Farmacêuticos , Pandemias/prevenção & controle , Estudos Transversais , Emergências , Papel Profissional , Brasil/epidemiologia , PercepçãoRESUMO
The low-protein, high-carbohydrate (LPHC) diet administered to growing rats soon after weaning, for 15 days, promoted an increase in energy expenditure by uncoupling protein 1 (UCP1) in interscapular brown adipose tissue, and also due to the occurrence of the browning process in the perirenal white adipose tissue (periWAT). However, we believe that inguinal white adipose tissue (ingWAT) may also contribute to energy expenditure through other mechanisms. Therefore, the aim of this work is to investigate the presence of the futile creatine cycle, and the origin of lipids in ingWAT, since that tissue showed an increase in the lipids content in rats submitted to the LPHC diet for 15 days. We observed increases in creatine kinase and alkaline phosphatase activity in ingWAT, of the LPHC animals. The mitochondrial Nicotinamide adenine dinucleotide reduced/nicotinamide adenine dinucleotide oxidized ratio is lower in ingWAT of LPHC animals. In the LPHC animals treated with ß-guanidinopropionic acid, the extracellular uptake of creatine in ingWAT was lower, as was the rectal temperature. Regarding lipid metabolism, we observed that in ingWAT, lipolysis in vitro when stimulated with noradrenaline is lower, and there were no changes in baseline levels. In addition, increases in the activity of enzymes were also observed: malic, glucose-6-phosphate dehydrogenase, and ATP-citrate lyase, in addition to an increase in the PPARγ content. The results show the occurrence of the futile creatine cycle in ingWAT, and that the increase in the relative mass may be due to an increase in de novo fatty acid synthesis.
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Creatina , Ácidos Graxos , Ratos , Animais , Creatina/metabolismo , Ratos Wistar , Ácidos Graxos/metabolismo , NAD/metabolismo , Tecido Adiposo Branco/metabolismo , Dieta com Restrição de Proteínas , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo/metabolismoRESUMO
While Earth contains the only known example of life in the universe, it is possible that life elsewhere is fundamentally different from what we are familiar with. There is an increased recognition in the astrobiology community that the search for life should steer away from terran-specific biosignatures to those that are more inclusive to all life-forms. To start exploring the space of possibilities that life could occupy, we can try to dissociate life from the chemistry that composes it on Earth by envisioning how different life elsewhere could be in composition, lifestyle, medium, and form, and by exploring how the general principles that govern living systems on Earth might be found in different forms and environments across the Solar System. Exotic life-forms could exist on Mars or Venus, or icy moons like Europa and Enceladus, or even as a shadow biosphere on Earth. New perspectives on agnostic biosignature detection have also begun to emerge, allowing for a broader and more inclusive approach to seeking exotic life with unknown chemistry that is distinct from life as we know it on Earth.
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Meio Ambiente Extraterreno , Júpiter , Meio Ambiente Extraterreno/química , Exobiologia , Sistema Solar , Planeta TerraRESUMO
The question "What is life?" has existed since the beginning of recorded history. However, the scientific and philosophical contexts of this question have changed and been refined as advancements in technology have revealed both fine details and broad connections in the network of life on Earth. Understanding the framework of the question "What is life?" is central to formulating other questions such as "Where else could life be?" and "How do we search for life elsewhere?" While many of these questions are addressed throughout the Astrobiology Primer 3.0, this chapter gives historical context for defining life, highlights conceptual characteristics shared by all life on Earth as well as key features used to describe it, discusses why it matters for astrobiology, and explores both challenges and opportunities for finding an informative operational definition.
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Planeta Terra , Exobiologia , Projetos de PesquisaRESUMO
The Astrobiology Primer 3.0 (ABP3.0) is a concise introduction to the field of astrobiology for students and others who are new to the field of astrobiology. It provides an entry into the broader materials in this supplementary issue of Astrobiology and an overview of the investigations and driving hypotheses that make up this interdisciplinary field. The content of this chapter was adapted from the other 10 articles in this supplementary issue and thus represents the contribution of all the authors who worked on these introductory articles. The content of this chapter is not exhaustive and represents the topics that the authors found to be the most important and compelling in a dynamic and changing field.
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Exobiologia , Estudantes , Humanos , Exobiologia/educaçãoRESUMO
Background: Personalized targeted therapies have transformed management of several solid tumors. Timely and accurate detection of clinically relevant genetic variants in tumor is central to the implementation of molecular targeted therapies. To facilitate precise molecular testing in solid tumors, targeted next-generation sequencing (NGS) assays have emerged as a valuable tool. In this study, we provide an overview of the technical validation, diagnostic yields, and spectrum of variants observed in 3,164 solid tumor samples that were tested as part of the standard clinical diagnostic assessment in an academic healthcare institution over a period of 2 years. Methods: The Ion Ampliseq™ Cancer Hotspot Panel v2 assay (ThermoFisher) that targets ~2,800 COSMIC mutations from 50 oncogenes and tumor suppressor genes was validated, and a total of 3,164 tumor DNA samples were tested in 2 years. A total of 500 tumor samples were tested by the comprehensive panel containing all the 50 genes. Other samples, including 1,375 lung cancer, 692 colon cancer, 462 melanoma, and 135 brain cancer, were tested by tumor-specific targeted subpanels including a few clinically actionable genes. Results: Of 3,164 patient samples, 2,016 (63.7%) tested positive for at least one clinically relevant variant. Of 500 samples tested by a comprehensive panel, 290 had a clinically relevant variant with TP53, KRAS, and PIK3CA being the most frequently mutated genes. The diagnostic yields in major tumor types were as follows: breast (58.4%), colorectal (77.6%), lung (60.4%), pancreatic (84.6%), endometrial (72.4%), ovary (57.1%), and thyroid (73.9%). Tumor-specific targeted subpanels also demonstrated high diagnostic yields: lung (69%), colon (61.2%), melanoma (69.7%), and brain (20.7%). Co-occurrence of mutations in more than one gene was frequently observed. Conclusions: The findings of our study demonstrate the feasibility of integrating an NGS-based gene panel screen as part of a standard diagnostic protocol for solid tumor assessment. High diagnostic rates enable significant clinical impact including improved diagnosis, prognosis, and clinical management in patients with solid tumors.