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1.
Nature ; 628(8006): 99-103, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38538794

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.

2.
Anticancer Drugs ; 35(7): 638-640, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38513159

RESUMO

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.


Assuntos
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 , Pirimidinas
3.
Clin Exp Rheumatol ; 42(2): 367-376, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38488092

RESUMO

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.


Assuntos
Miosite , Escleroderma Sistêmico , Humanos , Feminino , Masculino , Angioscopia Microscópica , Unhas/irrigação sanguínea , Miosite/complicações , Capilares , Autoanticorpos , Escleroderma Sistêmico/diagnóstico
4.
Inorg Chem ; 63(21): 9953-9966, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38757795

RESUMO

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.

5.
Bioessays ; 44(12): e2200037, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36209392

RESUMO

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.


Assuntos
Carotenoides , Pigmentação , Animais , Pigmentação/genética , Reprodutibilidade dos Testes , Carotenoides/metabolismo , Aves/genética , Expressão Gênica
6.
Proc Natl Acad Sci U S A ; 118(33)2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34385324

RESUMO

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.


Assuntos
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/genética
7.
J Am Pharm Assoc (2003) ; 64(4S): 102159, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39127940

RESUMO

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 , 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 terapêutico
8.
J Am Pharm Assoc (2003) ; 64(3): 102063, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38432480

RESUMO

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 terapêutico
9.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38473963

RESUMO

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.


Assuntos
Neoplasias do Colo , Citostáticos , Humanos , Citostáticos/farmacologia , Mitógenos/farmacologia , Transdução de Sinais , Proteínas Mitocondriais/metabolismo , Proliferação de Células , Proteínas de Transporte/metabolismo
10.
Int J Mol Sci ; 25(17)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39273608

RESUMO

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.


Assuntos
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/metabolismo
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