RESUMO
Stable aluminosilicate zeolites with extra-large pores that are open through rings of more than 12 tetrahedra could be used to process molecules larger than those currently manageable in zeolite materials. However, until very recently1-3, they proved elusive. In analogy to the interlayer expansion of layered zeolite precursors4,5, we report a strategy that yields thermally and hydrothermally stable silicates by expansion of a one-dimensional silicate chain with an intercalated silylating agent that separates and connects the chains. As a result, zeolites with extra-large pores delimited by 20, 16 and 16 Si tetrahedra along the three crystallographic directions are obtained. The as-made interchain-expanded zeolite contains dangling Si-CH3 groups that, by calcination, connect to each other, resulting in a true, fully connected (except possible defects) three-dimensional zeolite framework with a very low density. Additionally, it features triple four-ring units not seen before in any type of zeolite. The silicate expansion-condensation approach we report may be amenable to further extra-large-pore zeolite formation. Ti can be introduced in this zeolite, leading to a catalyst that is active in liquid-phase alkene oxidations involving bulky molecules, which shows promise in the industrially relevant clean production of propylene oxide using cumene hydroperoxide as an oxidant.
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Mutations in tyrosine kinase domain of epidermal growth factor receptor (EGFR) are observed in approximately 15% of non-small cell lung cancer adenocarcinoma. Exon 19 deletions or exon 21 L858R mutations are predominant in frequency and show high sensitivity to EGFR tyrosine kinase inhibitors (TKIs). Exon 18 mutations are extremely rare and the delE709_T710insD mutation accounts for only 0.16% of mutations when occurring as a sole mutation. This specific mutation in exon 18 seems to respond to certain EGFR TKIs such as afatinib. However, given the rarity of this mutation, determining the most effective TKI for its treatment remains unclear. We report a 70-year-old woman diagnosed with stage IV-A lung adenocarcinoma harboring EGFR delE709_T710insD mutation treated in first-line with Osimertinib using standard schedule and doses experiencing renal toxicity and disease progression after 9 weeks of treatment.
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Acrilamidas , Compostos de Anilina , Carcinoma Pulmonar de Células não Pequenas , Receptores ErbB , Éxons , Neoplasias Pulmonares , Humanos , Compostos de Anilina/uso terapêutico , Acrilamidas/uso terapêutico , Feminino , Idoso , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Receptores ErbB/genética , Mutação , Inibidores de Proteínas Quinases/uso terapêutico , Antineoplásicos/uso terapêutico , Estadiamento de Neoplasias , Indóis , PirimidinasRESUMO
OBJECTIVES: To assess nailfold video capillaroscopic (NVC) abnormalities and their association with clinical features, myositis-specific autoantibodies (MSA), and myositis-associated antibodies (MAA) in a large multi-ethnic cohort of patients with idiopathic inflammatory myopathies (IIM). METHODS: We recruited 155 IIM patients from three centres in Mexico, Spain, and the USA. We evaluated the clinical and laboratory features of the patients and performed semiquantitative and quantitative analyses of the NVC. Each NVC study was defined as having a normal, non-specific, early systemic sclerosis (SSc), active SSc, or late SSc pattern. Twenty-three patients had at least one follow-up NVC when disease control was achieved. Quantitative variables were expressed as medians and interquartile range (IQR) and were compared with the Kruskal-Wallis, the Mann-Whitney U-test, and the Wilcoxon test for paired medians. Associations between qualitative variables were assessed with the χ2 test. RESULTS: Most patients were women (68.3%), Hispanic (73.5%), and had dermatomyositis (DM) (61.2%). Fourteen patients (9%) had a normal NVC. A non-specific abnormality pattern was the most frequent (53.9%), and was associated with joint involvement, interstitial lung disease, Jo1 autoantibodies, anti-synthetase syndrome, and immune-mediated necrotising myopathy. The SSc pattern was observed mostly in DM and overlap myositis and was associated with cutaneous features and anti-TIF-1g autoantibodies. After treatment, there was a decrease in the capillaroscopic score, the capillary diameter, and the number of avascular areas, and an increase in capillary density and bushy capillary number. CONCLUSIONS: NVC abnormalities are related to the diagnosis, clinical features, disease activity, and autoantibodies of patients with IIM.
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Miosite , Escleroderma Sistêmico , Humanos , Feminino , Masculino , Angioscopia Microscópica , Unhas/irrigação sanguínea , Miosite/complicações , Capilares , Autoanticorpos , Escleroderma Sistêmico/diagnósticoRESUMO
For zeolites synthesized using imidazolium cations, the organic matter can be extracted at very low temperatures (100 °C) using ozone. This is possible for zeolites with 12-ring or larger pores but requires higher temperatures in medium-pore zeolites. The first chemical events in this process occur fast, even at room temperature, and imply the loss of aromaticity likely by the formation of an adduct between ozone and the imidazole ring through carbons C4 and C5. Subsequent rupture of the imidazole ring provides smaller and more flexible fragments that can desorb more readily. This process has been studied experimentally, mainly through infrared spectroscopy, and theoretically by density functional theory. Amazingly, fluoride anions occluded in the small double-four-ring units (d4r) during the synthesis remain inside the cage throughout the whole process when the temperature is not too high (≤150 °C). However, fluoride in larger cages in MFI ends up bonded to silicon in penta or hexacoordinated units, likely out of the cages, after ozone treatment at 150 °C. For several germanosilicate zeolites, the process allows their subsequent degermanation to yield stable high-silica zeolites. Quaternary ammonium cations require harsher conditions that eventually also extract fluoride from zeolite cages, including the d4r unit.
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In many vertebrates, the enzymatic oxidation of dietary yellow carotenoids generates red keto-carotenoids giving color to ornaments. The oxidase CYP2J19 is here a key effector. Its purported intracellular location suggests a shared biochemical pathway between trait expression and cell functioning. This might guarantee the reliability of red colorations as individual quality signals independent of production costs. We hypothesize that the ornament type (feathers vs. bare parts) and production costs (probably CYP2J19 activity compromising vital functions) could have promoted tissue-specific gene relocation. We review current avian tissue-specific CYP2J19 expression data. Among the ten red-billed species showing CYP2J19 bill expression, only one showed strong hepatic expression. Moreover, a phylogenetically-controlled analysis of 25 red-colored species shows that those producing red bare parts are less likely to have strong hepatic CYP2J19 expression than species with only red plumages. Thus, both production costs and shared pathways might have contributed to the evolution of red signals.
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Carotenoides , Pigmentação , Animais , Pigmentação/genética , Reprodutibilidade dos Testes , Carotenoides/metabolismo , Aves/genética , Expressão GênicaRESUMO
As phosphorus is one of the most limiting nutrients in many natural and agricultural ecosystems, plants have evolved strategies that cope with its scarcity. Genetic approaches have facilitated the identification of several molecular elements that regulate the phosphate (Pi) starvation response (PSR) of plants, including the master regulator of the transcriptional response to phosphate starvation PHOSPHATE STARVATION RESPONSE1 (PHR1). However, the chromatin modifications underlying the plant transcriptional response to phosphate scarcity remain largely unknown. Here, we present a detailed analysis of changes in chromatin accessibility during phosphate starvation in Arabidopsis thaliana root cells. Root cells undergo a genome-wide remodeling of chromatin accessibility in response to Pi starvation that is often associated with changes in the transcription of neighboring genes. Analysis of chromatin accessibility in the phr1 phl2 double mutant revealed that the transcription factors PHR1 and PHL2 play a key role in remodeling chromatin accessibility in response to Pi limitation. We also discovered that PHR1 and PHL2 play an important role in determining chromatin accessibility and the associated transcription of many genes under optimal Pi conditions, including genes involved in the PSR. We propose that a set of transcription factors directly activated by PHR1 in Pi-starved root cells trigger a second wave of epigenetic changes required for the transcriptional activation of the complete set of low-Pi-responsive genes.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genoma de Planta , Fosfatos/administração & dosagem , Fosfatos/farmacologia , Fatores de Transcrição/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Cromatina/metabolismo , Fosfatos/metabolismo , Raízes de Plantas/citologia , Fatores de Transcrição/genéticaRESUMO
BACKGROUND: Literature on pregabalin use in patients with heart failure is largely limited to patient case reports and cohort studies. OBJECTIVE: This study aimed to evaluate the effect of pregabalin initiation on diuretic requirements in patients with heart failure. METHODS: A retrospective analysis of patients with heart failure who were started on pregabalin between January 1, 2014, and September 1, 2021, at the Veterans Affairs North Texas Health Care System was used. The primary objective was to determine the median change in loop diuretic dose, in furosemide dose equivalents, 6 months after pregabalin initiation. RESULTS: Of 58 patients analyzed, there was no statistically significant difference in the primary outcome (P = 0.162). The secondary outcomes were found to be nonstatistically significant, and there was no correlation between pregabalin dose and outcomes. CONCLUSION: This represents the largest analysis of diuretic dose requirements in patients with heart failure after initiation of pregabalin. Although there was no difference in the median change of diuretic dose prescribed, pregabalin should still be used with caution.
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Insuficiência Cardíaca , Pregabalina , Humanos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Pregabalina/administração & dosagem , Pregabalina/uso terapêutico , Estudos Retrospectivos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Furosemida/administração & dosagem , Furosemida/uso terapêutico , Texas , Idoso de 80 Anos ou mais , Diuréticos/administração & dosagem , Diuréticos/uso terapêutico , Doença Crônica/tratamento farmacológico , Relação Dose-Resposta a Droga , Inibidores de Simportadores de Cloreto de Sódio e Potássio/administração & dosagem , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêuticoRESUMO
BACKGROUND: Literature on pregabalin use in patients with heart failure is largely limited to patient case reports and cohort studies. OBJECTIVE: This study aimed to evaluate the effect of pregabalin initiation on diuretic requirements in patients with heart failure. METHODS: A retrospective analysis of patients with heart failure who were started on pregabalin between January 1, 2014, and September 1, 2021, at the Veterans Affairs North Texas Health Care System was used. The primary objective was to determine the median change in loop diuretic dose, in furosemide dose equivalents, 6 months after pregabalin initiation. RESULTS: Of 58 patients analyzed, there was no statistically significant difference in the primary outcome (P = 0.162). The secondary outcomes were found to be nonstatistically significant, and there was no correlation between pregabalin dose and outcomes. CONCLUSION: This represents the largest analysis of diuretic dose requirements in patients with heart failure after initiation of pregabalin. Although there was no difference in the median change of diuretic dose prescribed, pregabalin should still be used with caution.
Assuntos
Insuficiência Cardíaca , Pregabalina , Humanos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/fisiopatologia , Pregabalina/administração & dosagem , Pregabalina/uso terapêutico , Estudos Retrospectivos , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Furosemida/administração & dosagem , Furosemida/uso terapêutico , Texas , Idoso de 80 Anos ou mais , Doença Crônica/tratamento farmacológico , Diuréticos/administração & dosagem , Diuréticos/uso terapêutico , Relação Dose-Resposta a Droga , Inibidores de Simportadores de Cloreto de Sódio e Potássio/administração & dosagem , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêuticoRESUMO
The protein p32 (C1QBP) is a multifunctional and multicompartmental homotrimer that is overexpressed in many cancer types, including colon cancer. High expression levels of C1QBP are negatively correlated with the survival of patients. Previously, we demonstrated that C1QBP is an essential promoter of migration, chemoresistance, clonogenic, and tumorigenic capacity in colon cancer cells. However, the mechanisms underlying these functions and the effects of specific C1QBP protein inhibitors remain unexplored. Here, we show that the specific pharmacological inhibition of C1QBP with the small molecule M36 significantly decreased the viability rate, clonogenic capacity, and proliferation rate of different colon cancer cell lines in a dose-dependent manner. The effects of the inhibitor of C1QBP were cytostatic and non-cytotoxic, inducing a decreased activation rate of critical pro-malignant and mitogenic cellular pathways such as Akt-mTOR and MAPK in RKO colon cancer cells. Additionally, treatment with M36 significantly affected the mitochondrial integrity and dynamics of malignant cells, indicating that p32/C1QBP plays an essential role in maintaining mitochondrial homeostasis. Altogether, our results reinforce that C1QBP is an important oncogene target and that M36 may be a promising therapeutic drug for the treatment of colon cancer.
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Neoplasias do Colo , Citostáticos , Humanos , Citostáticos/farmacologia , Mitógenos/farmacologia , Transdução de Sinais , Proteínas Mitocondriais/metabolismo , Proliferação de Células , Proteínas de Transporte/metabolismoRESUMO
The coronavirus disease 2019 (COVID-19) survivors are frequently observed to present persistent symptoms constituting what has been called "post-acute COVID-19 syndrome" (PACS) or "long COVID-19". Some clinical risk factors have been identified to be associated with PACS development; however, specific mechanisms responsible for PACS pathology remain unknown. This study investigates clinical, immunological, and metabolomic risk factors associated with post-acute COVID-19 syndrome (PACS) in 51 patients, assessed 7-19 months after acute infection. Among the participants, 62.7% were male and 37.2% were female, with an average age of 47.8 years. At the follow-up, 37.2% met the criteria for PACS, revealing significant differences in immunological and metabolomic profiles at the time of acute infection. Patients with PACS were characterized by elevated levels of mature low-density granulocytes (LDGs), interleukin-8 (IL-8), pyruvate, pseudouridine, and cystine. Baseline multivariate analysis showed increased pyruvate and decreased alpha tocopherol levels. At follow-up, there was a decrease in absolute B lymphocytes and an increase in non-classical monocytes and 3-hydroxyisovaleric acid levels. These findings suggest that specific immunological and metabolomic markers during acute infection can help identify patients at higher risk of developing persistent PACS.
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COVID-19 , Síndrome de COVID-19 Pós-Aguda , SARS-CoV-2 , Humanos , Feminino , COVID-19/imunologia , COVID-19/metabolismo , COVID-19/complicações , Masculino , Pessoa de Meia-Idade , Adulto , Fatores de Risco , Biomarcadores , Metabolômica/métodos , Idoso , Metaboloma , Interleucina-8/metabolismoRESUMO
BACKGROUND: Betaglycan, also known as the TGFß type III receptor (Tgfbr3), is a co-receptor that modulates TGFß family signaling. Tgfbr3 is upregulated during C2C12 myoblast differentiation and expressed in mouse embryos myocytes. RESULTS: To investigate tgfbr3 transcriptional regulation during zebrafish embryonic myogenesis, we cloned a 3.2 kb promoter fragment that drives reporter transcription during C2C12 myoblasts differentiation and in the Tg(tgfbr3:mCherry) transgenic zebrafish. We detect tgfbr3 protein and mCherry expression in the adaxial cells concomitantly with the onset of their radial migration to become slow-twitch muscle fibers in the Tg(tgfbr3:mCherry). Remarkably, this expression displays a measurable antero-posterior somitic gradient expression. CONCLUSIONS: tgfbr3 is transcriptionally regulated during somitic muscle development in zebrafish with an antero-posterior gradient expression that preferentially marks the adaxial cells and their descendants.
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Somitos , Peixe-Zebra , Animais , Camundongos , Somitos/metabolismo , Proteoglicanas/metabolismo , Fibras Musculares de Contração Lenta/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Desenvolvimento Muscular/fisiologiaRESUMO
Background and Objectives: Medical and public recognition of "long-COVID or post-COVID syndrome", as well as its impact on the quality of life (QoL), is required to better address the disease burden. Objectives: We aimed to describe the persistence of COVID-19 symptoms and QoL among patients at three and twelve months after their discharge from the hospital. Materials and Methods: We conducted an observational, prospective, and longitudinal analytic study from September 2021 to April 2022. To measure QoL, we used a validated version of the 36-item Short-Form Health Survey (SF-36). Results: We included 68 patients in the study. A total of 54 (79.4%) patients reported at least one persistent symptom at three months vs. 52 (76.4%) at twelve months (p = 0.804). Some persistent symptoms (myalgia, alopecia, and cough) decreased significantly at twelve months (50% vs. 30.9%, 29.4% vs. 13.2%, and 23.5% vs. 7.4%; respectively, p = 0.007); in contrast, other persistent symptoms (sleep-wake and memory disorders) were more frequent (5.9% vs. 32.4% and 4.4% vs. 20.6%; respectively, p = ≤0.001). Regarding QoL, a statistically significant improvement was observed in some scores over time, p = ≤0.037. At twelve months, dyspnea, myalgia, and depression were risk factors associated with a poor physical component summary (PCS), p = ≤0.027, whereas anxiety, depression, and fatigue were associated with a poor mental component summary (MCS), p = ≤0.015. Conclusion: As the proportion of persistent symptoms at twelve months is high, we suggest that patients must continue under long-term follow up to reclassify, diagnose, and treat new onset symptoms/diseases.
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COVID-19 , Alta do Paciente , Qualidade de Vida , Humanos , COVID-19/psicologia , Feminino , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos Longitudinais , Idoso , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda , Adulto , Mialgia , Fatores de Tempo , Tosse/psicologia , Alopecia/psicologiaRESUMO
BACKGROUND: Recent studies suggest that metformin use may be associated with improved infectious disease-related outcomes, whereas other papers suggest potentially worse outcomes in serious bacterial infections. Our purpose was to examine the association of prior outpatient prescription of metformin on 30- and 90-day mortality for older veterans with pre-existing diabetes hospitalized with pneumonia. METHODS: We conducted a retrospective cohort study using national Department of Veterans Affairs data of patients ≥65 years with a prior history of diabetes who were hospitalized with pneumonia over a 10-year period (fiscal years 2002-2012.) For our primary analysis, we created a propensity score and matched metformin users to nonusers 1:1. RESULTS: We identified 34 759 patients who met the inclusion criteria, 20.3% of whom were prescribed metformin. Unadjusted 30-day mortality was 9.6% for those who received metformin versus 13.9% in nonusers (P < .003), and 90-day mortality was 15.8% for those who received metformin versus 23.0% for nonusers (P < .0001). For the propensity score model, we matched 6899 metformin users to 6899 nonusers. After propensity matching, both 30-day (relative risk [RR]: .86; 95% confidence interval [CI]: .78-.95) and 90-day (RR: .85; 95% CI: .79-.92) mortality was significantly lower for metformin users. CONCLUSIONS: Prior receipt of metformin was associated with significantly lower mortality after adjusting for potential confounders. Additional research is needed to examine the safety and potential benefits of metformin use in patients with respiratory infections.
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Diabetes Mellitus Tipo 2 , Metformina , Pneumonia , Veteranos , Humanos , Metformina/uso terapêutico , Hipoglicemiantes/uso terapêutico , Estudos Retrospectivos , Diabetes Mellitus Tipo 2/complicações , Pneumonia/tratamento farmacológico , Pneumonia/complicaçõesRESUMO
COVID-19 outbreak is the biggest threat to human health in recent history. Currently, there are over 1.5 million related deaths and 75 million people infected around the world (as of 22/12/2020). The identification of virulence factors which determine disease susceptibility and severity in different cell types remains an essential challenge. The serine protease TMPRSS2 has been shown to be important for S protein priming and viral entry, however, little is known about its regulation. SPINT2 is a member of the family of Kunitz type serine protease inhibitors and has been shown to inhibit TMPRSS2. Here, we explored the existence of a co-regulation between SPINT2/TMPRSS2 and found a tightly regulated protease/inhibitor expression balance across tissues. We found that SPINT2 negatively correlates with SARS-CoV-2 expression in Calu-3 and Caco-2 cell lines and was down-regulated in secretory cells from COVID-19 patients. We validated our findings using Calu-3 cell lines and observed a strong increase in viral load after SPINT2 knockdown, while overexpression lead to a drastic reduction of the viral load. Additionally, we evaluated the expression of SPINT2 in datasets from comorbid diseases using bulk and scRNA-seq data. We observed its down-regulation in colon, kidney and liver tumors as well as in alpha pancreatic islets cells from diabetes Type 2 patients, which could have implications for the observed comorbidities in COVID-19 patients suffering from chronic diseases.
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COVID-19/metabolismo , Glicoproteínas de Membrana/metabolismo , SARS-CoV-2/metabolismo , Internalização do Vírus , Células A549 , COVID-19/genética , Células CACO-2 , Humanos , Glicoproteínas de Membrana/genética , SARS-CoV-2/genética , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Índice de Gravidade de DoençaRESUMO
OBJECTIVE: To assess the proportion of myeloid-derived suppressor cells (MDSCs), their expression of arginase-1 and programmed cell death ligand 1 (PD-L1) and their relationship with the clinical phenotype of patients with idiopathic inflammatory myopathies (IIMs). METHODS: We recruited 37 IIM adult patients and 10 healthy donors in Mexico City. We evaluated their clinical features, the proportion of MDSCs and their expression of PD-L1 and arginase-1 by flow cytometry. Polymorphonuclear (PMN)-MDSCs were defined as CD33dim, CD11b+ and CD66b+ while monocytic (M)-MDSCs were CD33+, CD11b+, HLA-DR- and CD14+. Serum cytokines were analysed with a multiplex assay. We compared the quantitative variables with the Kruskal-Wallis and Mann-Whitney U tests and assessed correlations with Spearman's ρ. RESULTS: Most patients had dermatomyositis [n = 30 (81.0%)]. IIM patients had a peripheral expansion of PMN-MDSCs and M-MDSCs with an enhanced expression of arginase-1 and PD-L1. Patients with active disease had a decreased percentage {median 1.75% [interquartile range (IQR) 0.31-5.50 vs 10.71 [3.16-15.58], P = 0.011} of M-MDSCs and a higher absolute number of PD-L1+ M-MDSCs [median 23.21 cells/mm3 (IQR 11.16-148.9) vs 5.95 (4.66-102.7), P = 0.046] with increased expression of PD-L1 [median 3136 arbitrary units (IQR 2258-4992) vs 1961 (1885-2335), P = 0.038]. PD-L1 expression in PMN-MDSCs correlated with the visual analogue scale of pulmonary disease activity (r = 0.34, P = 0.040) and damage (r = 0.36, P = 0.031), serum IL-5 (r = 0.55, P = 0.003), IL-6 (r = 0.46, P = 0.003), IL-8 (r = 0.53, P = 0.018), IL-10 (r = 0.48, P = 0.005) and GM-CSF (r = 0.48, P = 0.012). M-MDSCs negatively correlated with the skeletal Myositis Intention to Treat Index (r = -0.34, P = 0.038) and positively with IL-6 (r = 0.40, P = 0.045). CONCLUSION: MDSCs expressing arginase-1 and PD-L1 are expanded in IIM and correlate with disease activity, damage accrual and serum cytokines.
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Células Supressoras Mieloides , Arginase/genética , Arginase/metabolismo , Interleucina-6/metabolismo , Antígeno B7-H1/metabolismo , Citocinas/metabolismoRESUMO
Fungal nanochitin can assist the transition from the linear fossil-based economy to a circular biobased economy given its environmental benefits over conventional crustacean-nanochitin. Its real-world implementation requires carefully assessing its toxicity so that unwanted human health and environmental issues are avoided. Accordingly, the cytotoxicity and inflammatory effects of chitin nanofibrils (ChNFs) from white mushroom is assessed. ChNFs are few nanometers in diameter, with a 75.8% N-acetylation degree, a crystallinity of 59.1%, and present a 44:56 chitin/glucan weight ratio. Studies are conducted for aqueous colloidal ChNF dispersions (0-5 mg·mL-1) and free-standing films having physically entangled ChNFs. Aqueous dispersions of chitin nanocrystals (ChNCs) isolated via hydrochloric acid hydrolysis of α-chitin powder are also evaluated for comparison. Cytotoxicity studies conducted in human fibroblasts (MRC-5 cells) and murine brain microglia (BV-2 cells) reveal a comparatively safer behavior over related biobased nanomaterials. However, a strong inflammatory response was observed when BV-2 cells were cultured in the presence of colloidal ChNFs. These novel cytotoxicity and inflammatory studies shed light on the potential of fungal ChNFs for biomedical applications.
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Nanofibras , Nanoestruturas , Humanos , Animais , Camundongos , Nanofibras/química , Quitina/farmacologia , Quitina/química , Glucanos , Água/química , FungosRESUMO
Six Gram-negative, rod-shaped bacterial strains isolated from Heterorhabditis amazonensis entomopathogenic nematodes were characterized to determine their taxonomic position. 16S rRNA and gyrB gene sequences indicate that they belong to the class Gammaproteobacteria, family Morganellaceae and genus Photorhabdus, and that some of them are conspecifics. Two of them, APURET and JART, were selected for further molecular characterization using whole genome- and whole-proteome-based phylogenetic reconstructions and sequence comparisons. Phylogenetic reconstructions using whole genome and whole proteome sequences show that strains APURET and JART are closely related to Photorhabdus luminescens subsp. luminescens ATCC 29999T and to P. luminescens subsp. mexicana MEX47-22T. Moreover, digital DNA-DNA hybridization (dDDH) values between APURET and P. luminescens subsp. luminescens ATCC 29999T, APURET and P. luminescens subsp. mexicana MEX47-22T, and APURET and JART are 61.6, 61.2 and 64.1â%, respectively. These values are below the 70â% divergence threshold that delimits prokaryotic species. dDDH scores between JART and P. luminescens subsp. luminescens ATCC 29999T and between JART and P. luminescens subsp. mexicana MEX47-22T are 71.9 and 74.8â%, respectively. These values are within the 70 and 79â% divergence thresholds that delimit prokaryotic subspecies. Based on these genomic divergence values, APURET and JART represent two different taxa, for which we propose the names: Photorhabdus aballayi sp. nov. with APURET (=CCM 9236T =CCOS 2019T) as type strain and Photorhabdus luminescens subsp. venezuelensis subsp. nov. with JART (=CCM 9235T =CCOS 2021T) as type strain. Our study contributes to a better understanding of the biodiversity of an important bacterial group with enormous biotechnological and agricultural potential.
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Nematoides , Photorhabdus , Animais , Filogenia , RNA Ribossômico 16S/genética , Proteoma/genética , Técnicas de Tipagem Bacteriana , Análise de Sequência de DNA , DNA Bacteriano/genética , Composição de Bases , Ácidos Graxos/química , Nematoides/microbiologiaRESUMO
BACKGROUND: Continuity of care (CoC) is an important component of health care delivery that can have cost implications and improve patient outcomes. We analysed data obtained from the Department of Veterans Affairs to examine the relationship between CoC and use of image-oriented diagnostic tests in patients with comorbid chronic conditions. METHODS: A longitudinal, retrospective cohort study involving participants ≥18 years old, with comorbid diabetes and chronic kidney disease. We used a multivariate linear regression model to test whether greater care continuity, measured using a care continuity index (CCI), is associated with less frequent use of diagnostic tests. RESULTS: Total of 267,442 patients and 8,142,036 tests were included. Of the diagnostic tests we chose to evaluate, the 4 most frequently ordered tests were X-ray (45.6%), electrocardiogram (EKG, 16.8%), computerized tomography (CT, 13.4%), and magnetic resonance imaging (MRI, 3.4%). Overall, greater CCI was associated with fewer use of tests (P < 0.001). A 1 standard deviation (SD, 0.27) increase in CCI was associated with 4.2% decrease (P < 0.001) in number of tests. But a mixed pattern existed. For X-ray and EKG, greater continuity was associated with less testing, 6.2% (P < 0.001) and 3.3% (P < 0.05) reductions, respectively. Whereas, for CT and MRI, greater continuity was associated with more testing, 2.3% (P < 0.001) and 1.4% increases (P < 0.01), respectively. CONCLUSION: Overall, greater CoC was associated with fewer use of tests, representing a greater presumed efficiency of care. This has implications for designing health care delivery.
Assuntos
Diabetes Mellitus , Veteranos , Humanos , Adolescente , Estudos Retrospectivos , Continuidade da Assistência ao Paciente , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , ComorbidadeRESUMO
Three bacterial strains, XENO-2T, XENO-7T, and XENO-10T, isolated from Steinernema entomopathogenic nematodes, were found to represent novel Xenorhabdus species. In this study, we describe these new species by whole-genome and whole-proteome phylogenomic reconstructions, by calculating sequence identity scores using core genome sequences, and by phenotypic characterization. Phylogenomic reconstructions using ribosomal and house-keeping genes, and whole-genome and whole-proteome sequences show that XENO-2T and XENO-10T are closely related to Xenorhabdus japonica DSM 16522T and that XENO-7T is closely related to Xenorhabdus bovienii subsp. africana XENO-1T and to X. bovienii subsp. bovienii T228T. The dDDH values between XENO-2T and XENO-10T and between XENO-2T and X. japonica DSM 16522T are 56.4 and 51.8%, respectively. The dDDH value between XENO-10T and X. japonica DSM 16522T is 53.4%. The dDDH values between XENO-7T and X. bovienii subsp. africana XENO-1T and between XENO-7T and X. bovienii subsp. bovienii T228T are 63.6 and 69.4%, respectively. These dDDH values are below the 70% divergence threshold for prokaryotic species delineation. The newly described species are highly pathogenic to G. mellonella larvae, grow at pH between 5 and 9 (optimum 5-7), at salt concentrations of 1-3% (optimum 1-2%), and temperatures between 20 and 37 °C (optimum 28-30 °C). Biochemical tests such as lysine decarboxylase, ornithine decarboxylase, urease, gelatinase, citrate utilization, indole and acetoin production, and cytochrome oxidase tests allow to differentiate the novel species from their more closely related species. Considering these genetic and phenotypic divergencies, we propose the following new species: Xenorhabdus aichiensis sp. nov. with XENO-7T (= CCM 9233T = CCOS 2024T) as the type strain, Xenorhabdus anantnagensis sp. nov., with XENO-2T (= CCM 9237T = CCOS 2023T) as the type strain, and Xenorhabdus yunnanensis sp. nov., with XENO-10T (= CCM 9322T = CCOS 2071T) as the type strain. Our study contributes to a better understanding of the biodiversity and phylogenetic relationships of entomopathogenic bacteria associated with insect parasitic nematodes.
Assuntos
Rabditídios , Xenorhabdus , Animais , Filogenia , Proteoma/genética , Simbiose , RNA Ribossômico 16S/genética , Rabditídios/genética , Rabditídios/microbiologia , DNA Bacteriano/genética , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , Ácidos GraxosRESUMO
BACKGROUND: Two of the most commonly used classifications for the posterior malleolus fracture are Haraguchi and Bartonícek. Both classifications are based on the morphology of the fracture. This study makes an inter- and intra-observer agreement analysis of the mentioned classifications. METHODS: 39 patients with ankle fractures who met inclusion criteria were selected. All the fractures were analyzed and classified twice by each of the 20 observers using Bartonícek and Haraguchi's classifications, with a window period of at least 30 days between the two rounds. RESULTS: Analysis was made by Kappa coefficient (Æ). The global intraobserver value was Æ = 0.627 in the Bartonícek classification and Æ = 0.644 in the Haraguchi one. The first round global interobserver Æ = 0.589 (0.574-0.604) on the Bartonícek classification and Æ = 0.534 (0.517-0.551) on the Haraguchi one. Second round coefficients were Æ = 0.601 (0.585-0.616) and Æ = 0.536 (0.519-0.554), respectively. The best agreement was when there was involvement of the posteromedial malleolar zone with Æ = 0.686 and Æ = 0.687 in Haraguchi II and Æ = 0.641 and Æ = 0.719 in Bartonícek III. No differences were observed in Kappa values when an experience-based analysis was made. CONCLUSION: Bartonícek and Haraguchi classifications of the posterior malleolus fracture have both substantial intraobserver agreement but moderate to substantial agreement in interobserver analysis. LEVEL OF EVIDENCE: IV.