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An iron-catalyzed selective N=S coupling of N-methoxy amides and sulfoxides has been developed and was found to be a highly efficient method for the synthesis of N-acyl sulfoximines. Electron-donating as well as electron-withdrawing groups on the phenyl ring are tolerated, and even sensitive substituents are compatible. The current catalytic transformation was conducted under an air atmosphere and can be easily scaled up to a gram scale with a catalyst loading of only 1 mol %. In this case, both coupling partners are used in their native forms, thus obviating prior functionalization and activation.
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Iron-modified Ni(OH)2/NiSe2 enhances oxygen vacancies, expanding the electrochemically active surface area, which exhibiting superior selectivity and stability in urea oxidation reaction, outperforming pristine Ni(OH)2@NiSe2. It also demonstrates superior catalytic performance in the oxidation reactions of other small molecules.
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Cytomegalovirus (CMV) infection is one of the most common infectious complications following hematopoietic stem cell transplantation (HSCT); however, cases involving multiple organs at the same time are rare. The present study describes a case of CMV pneumonia combined with CMV DNAemia and CMV cystitis after HSCT. A 33-year-old male patient with acute myeloid leukemia was treated with HSCT. The first month after HSCT, the patient developed a cough and shortness of breath. At 2 months post-HSCT, the patient developed hematuria. The CMV DNA levels in the blood and urine were elevated; bronchoalveolar lavage fluid (BALF) was also positive for CMV DNA. Heterotypic cells exhibiting a large nuclear morphology were observed in the BALF and bronchial brushes. Recurrent and progressive ground-glass opacities were evident on chest computed tomography. The patient was diagnosed with CMV pneumonia complicated by CMV DNAemia and CMV cystitis, and was treated with a combination of ganciclovir and foscarnet, along with immunoglobulin therapy. The patient was cured and discharged. It was determined that the CMV DNA in the blood was inconsistent with that in the BALF, which delayed the early diagnosis of CMV pneumonia. The association between T-cell immune function and the therapeutic efficacy for CMV multi-organ infection following HSCT is known to be significant. Moreover, the timely administration of ganciclovir and foscarnet in combination with immunoglobulin therapy demonstrated favorable clinical outcomes.
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The ternary complex (eIF2·GTP·Met-tRNAiMet) and the eIF4F complex assembly are two major regulatory steps in the eukaryotic translation initiation. Inhibition of the ternary complex assembly is therefore a promising target for the development of novel anti-cancer therapeutics. Building on the finding that clotrimazole (CLT), a molecular probe that depletes intracellular Ca2+ stores and subsequently induce eIF2α phosphorylation, inhibit translation initiation, and reduce preferentially the expression of oncoproteins over "housekeeping" ones,1-3 we undertook structure activity relationship (SAR) studies that identified 3,3-diarylindoline-2-one #1181 as an interesting scaffold. Compound #1181 also induce phosphorylation of eIF2α thereby reducing the availability of the ternary complex, which leads to inhibition of translation initiation.4 Our subsequent efforts focused on understanding SAR iterative lead optimization to enhance potency and improve bioavailability. Herein, we report a complementing study focusing on heavily substituted symmetric and asymmetric 3,3-(o,m-disubstituted)diarylindoline-2-ones. These compounds were evaluated by the dual luciferase reporter ternary complex assay that recapitualates phosphorylation of eIF2α in a quantitative manner. We also evaluated all compounds by sulforhodamine B assay, which measures the overall effect of compounds on cell proliferations and/or viability.
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Compostos de Bifenilo , Fator de Iniciação 2 em Eucariotos , Fator de Iniciação 2 em Eucariotos/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Fosforilação , Biossíntese de ProteínasRESUMO
OBJECTIVES: To compare the diagnostic accuracy of US shear wave elastography (SWE) and magnetic resonance elastography (MRE) for classifying fibrosis stage in patients with nonalcoholic fatty liver disease (NAFLD). METHODS: Patients from a prospective single-center cohort with clinical liver biopsy for known or suspected NAFLD underwent contemporaneous SWE and MRE. AUCs for classifying biopsy-determined liver fibrosis stages ≥ 1, ≥ 2, ≥ 3, and = 4, and their respective performance parameters at cutoffs providing ≥ 90% sensitivity or specificity were compared between SWE and MRE. RESULTS: In total, 100 patients (mean age, 51.8 ± 12.9 years; 46% males; mean BMI 31.6 ± 4.7 kg/m2) with fibrosis stage distribution (stage 0/1/2/3/4) of 43, 36, 5, 10, and 6%, respectively, were included. AUCs (and 95% CIs) for SWE and MRE were 0.65 (0.54-0.76) and 0.81 (0.72-0.89), 0.81 (0.71-0.91) and 0.94 (0.89-1.00), 0.85 (0.74-0.96) and 0.95 (0.89-1.00), and 0.91 (0.79-1.00) and 0.92 (0.83-1.00), for detecting fibrosis stage ≥ 1, ≥ 2, ≥ 3, and = 4, respectively. The differences were significant for detecting fibrosis stage ≥ 1 and ≥ 2 (p < 0.01) but not otherwise. At ≥ 90% sensitivity cutoff, MRE yielded higher specificity than SWE at diagnosing fibrosis stage ≥ 1, ≥ 2, and ≥ 3. At ≥ 90% specificity cutoff, MRE yielded higher sensitivity than SWE at diagnosing fibrosis stage ≥ 1 and ≥ 2. CONCLUSIONS: In adults with NAFLD, MRE was more accurate than SWE in diagnosing stage ≥ 1 and ≥ 2 fibrosis, but not stage ≥ 3 or 4 fibrosis. KEY POINTS: ⢠For detecting any fibrosis or mild fibrosis, MR elastography was significantly more accurate than shear wave elastography. ⢠For detecting advanced fibrosis and cirrhosis, MRE and SWE did not differ significantly in accuracy. ⢠For excluding advanced fibrosis and potentially ruling out the need for biopsy, SWE and MRE did not differ significantly in negative predictive value. ⢠Neither SWE nor MRE had sufficiently high positive predictive value to rule in advanced fibrosis.
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Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Adulto , Biópsia , Feminino , Fibrose , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia , Estudos ProspectivosRESUMO
OBJECTIVE: To analyze gene variants in a Chinese pedigree with oculocutaneous albinism (OCA). METHODS: Gene sequencing of the proband and his parents was performed using chip capture high-throughput sequencing and Sanger sequencing techniques, and PolyPhen-2, SIFT, MutationTaster, and FATHMM software were used to predict the function of new variants. At the same time,the pedigree and variant genes of 4 albinism patients from this pedigree were analyzed. RESULTS: Sequencing results showed that the proband's TYR gene (NM_000372) has c.230G>A (p.Arg77Gln) and c.120_121insG (p.Asp42GlyfsTer35) compound heterozygous variants. The proband's father carries c.230G>A heterozygous variant, and the mother carries c.120_121insG heterozygous variant, indicating that the proband's two variants are from his father and mother. The former is a known missense variant, which can cause abnormal or loss of the original function of the protein polypeptide chain. The latter c.120_121insG(p.Asp42GlyfsTer35) is an unreported frameshift variant of the TYR gene subregion (EX1; CDS1). PolyPhen-2, SIFT, MutationTaster and FATHMM predictions are all prompted as "harmful variants". This variant caused the amino acid encoded protein to terminate prematurely, producing a truncated protein, which eventually formed a 76-amino acid short-type TYR protein instead of the 529-amino acid wild-type TYR protein. Through the pedigree analysis, the four patients in the pedigree are all of the same type of compound heterozygous variants, and the disease-causing genes are all from the patient's parents. They belong to a special form of consanguineous marriage within 5 generations. CONCLUSION: The compound heterozygous variants of c.230G>A (p.Arg77Gln) and c.120_121insG (p.Asp42GlyfsTer35) of the TYR gene may underlie the disease in this pedigree. The gene sequencing results enrich the variant spectrum of the TYR gene, and has facilitated molecular diagnosis for the patient.
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Albinismo Oculocutâneo , Albinismo Oculocutâneo/genética , Consanguinidade , Heterozigoto , Humanos , Mutação , LinhagemRESUMO
OBJECTIVES: To investigate associations between histology and hepatic mechanical properties measured using multiparametric magnetic resonance elastography (MRE) in adults with known or suspected nonalcoholic fatty liver disease (NAFLD) without histologic fibrosis. METHODS: This was a retrospective analysis of 88 adults who underwent 3T MR exams including hepatic MRE and MR imaging to estimate proton density fat fraction (MRI-PDFF) within 180 days of liver biopsy. Associations between MRE mechanical properties (mean shear stiffness (|G*|) by 2D and 3D MRE, and storage modulus (G'), loss modulus (Gâ³), wave attenuation (α), and damping ratio (ζ) by 3D MRE) and histologic, demographic and anthropometric data were assessed. RESULTS: In univariate analyses, patients with lobular inflammation grade ≥ 2 had higher 2D |G*| and 3D Gâ³ than those with grade ≤ 1 (p = 0.04). |G*| (both 2D and 3D), G', and Gâ³ increased with age (rho = 0.25 to 0.31; p ≤ 0.03). In multivariable regression analyses, the association between inflammation grade ≥ 2 remained significant for 2D |G*| (p = 0.01) but not for 3D Gâ³ (p = 0.06); age, sex, or BMI did not affect the MRE-inflammation relationship (p > 0.20). CONCLUSIONS: 2D |G*| and 3D Gâ³ were weakly associated with moderate or severe lobular inflammation in patients with known or suspected NAFLD without fibrosis. With further validation and refinement, these properties might become useful biomarkers of inflammation. Age adjustment may help MRE interpretation, at least in patients with early-stage disease. KEY POINTS: ⢠Moderate to severe lobular inflammation was associated with hepatic elevated shear stiffness and elevated loss modulus (p =0.04) in patients with known or suspected NAFLD without liver fibrosis; this suggests that with further technical refinement these MRE-assessed mechanical properties may permit detection of inflammation before the onset of fibrosis in NAFLD. ⢠Increasing age is associated with higher hepatic shear stiffness, and storage and loss moduli (rho = 0.25 to 0.31; p ≤ 0.03); this suggests that age adjustment may help interpret MRE results, at least in patients with early-stage NAFLD.
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Técnicas de Imagem por Elasticidade , Hepatopatia Gordurosa não Alcoólica , Biomarcadores , Fibrose , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Imageamento por Ressonância Magnética , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/patologia , Estudos Prospectivos , Estudos RetrospectivosRESUMO
Liver fibrosis is a histological hallmark of most chronic liver diseases, which can progress to cirrhosis and liver failure, and predisposes to hepatocellular carcinoma. Accurate diagnosis of liver fibrosis is necessary for prognosis, risk stratification, and treatment decision-making. Liver biopsy, the reference standard for assessing liver fibrosis, is invasive, costly, and impractical for surveillance and treatment response monitoring. Elastography offers a noninvasive, objective, and quantitative alternative to liver biopsy. This article discusses the need for noninvasive assessment of liver fibrosis and reviews the comparative advantages and limitations of ultrasound and magnetic resonance elastography techniques with respect to their basic concepts, acquisition, processing, and diagnostic performance. Variations in clinical contexts of use and common pitfalls associated with each technique are considered. In addition, current challenges and future directions to improve the diagnostic accuracy and clinical utility of elastography techniques are discussed. Level of Evidence: 5 Technical Efficacy Stage: 2 J. Magn. Reson. Imaging 2020;51:25-42.
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Técnicas de Imagem por Elasticidade/métodos , Cirrose Hepática/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Humanos , Fígado/diagnóstico por imagemRESUMO
OBJECTIVES: The aim of this meta-analysis was to evaluate the diagnostic accuracy of hepatic magnetic resonance imaging-proton density fat fraction (MRI-PDFF) for the assessment of liver steatosis (LS) with histology as reference standard. METHODS: A systematic literature search was performed to identify pertinent studies. Quality analyses were conducted by Quality Assessment of Diagnostic Accuracy Studies-2. Diagnostic data were extracted and inconsistency index was calculated for LS≥G1, LS≥G2, and LS=G3, respectively. The area under summary receiver operating characteristic curve (AUC) served as the indicator of diagnostic accuracy. The pooled sensitivity and specificity were calculated if threshold effect was absent. RESULTS: Thirteen studies containing 1100 subjects were included. There was significant threshold effect for LS≥G1. The AUCs for LS≥G1, LS≥G2, and LS=G3 were 0.98 (95% confidence interval (CI) 0.76, 1.00), 0.91 (95% CI 0.89, 0.94), and 0.92 (95% CI 0.89, 0.94), respectively. The pooled sensitivities for LS≥G2 and LS=G3 were 0.83 (95% CI 0.75, 0.88) and 0.79 (95% CI 0.63, 0.90), respectively; the pooled specificities for LS≥G2 and LS=G3 were 0.89 (95% CI 0.84, 0.92) and 0.89 (95% CI 0.84, 0.92), respectively. CONCLUSIONS: MRI-PDFF has high diagnostic accuracy at detecting and grading LS with histology as reference standard, suggesting that MRI-PDFF is able to provide an accurate quantification of LS in clinical trials and patient care. KEY POINT: ⢠MRI-PDFF is able to provide an accurate quantification of LS in clinical trials and patient care.
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Biópsia/métodos , Fígado/patologia , Imageamento por Ressonância Magnética/métodos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Humanos , Curva ROC , Reprodutibilidade dos TestesRESUMO
Hepatic steatosis is a frequently encountered imaging finding that may indicate chronic liver disease, the most common of which is non-alcoholic fatty liver disease. Non-alcoholic fatty liver disease is implicated in the development of systemic diseases and its progressive phenotype, non-alcoholic steatohepatitis, leads to increased liver-specific morbidity and mortality. With the rising obesity epidemic and advent of novel therapeutics aimed at altering metabolism, there is a growing need to quantify and monitor liver steatosis. Imaging methods for assessing steatosis range from simple and qualitative to complex and highly accurate metrics. Ultrasound may be appropriate in some clinical instances as a screening modality to identify the presence of abnormal liver morphology. However, it lacks sufficient specificity and sensitivity to constitute a diagnostic modality for instigating and monitoring therapy. Newer ultrasound techniques such as quantitative ultrasound show promise in turning qualitative assessment of steatosis on conventional ultrasound into quantitative measurements. Conventional unenhanced CT is capable of detecting and quantifying moderate to severe steatosis but is inaccurate at diagnosing mild steatosis and involves the use of radiation. Newer CT techniques, like dual energy CT, show potential in expanding the role of CT in quantifying steatosis. MRI proton-density fat fraction is currently the most accurate and precise imaging biomarker to quantify liver steatosis. As such, proton-density fat fraction is the most appropriate noninvasive end point for steatosis reduction in clinical trials and therapy response assessment.
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Fígado/diagnóstico por imagem , Hepatopatia Gordurosa não Alcoólica/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
The growing recognition of inhibition of translation initiation as a new and promising paradigm for mechanism-based anti-cancer therapeutics is driving the development of potent, specific, and druggable inhibitors. The 3,3-diaryloxindoles were recently reported as potential inhibitors of the eIF2·GTP·Met-tRNAi(Met) ternary complex assembly and 3-{5-tert-butyl-2-hydroxyphenyl}-3-phenyl-1,3-dihydro-2H-indol-2-one #1181 was identified as the prototypic agent of this chemotype. Herein, we report our continuous effort to further develop this chemotype by exploring the structural latitude toward different polar and hydrophobic substitutions. Many of the novel compounds are more potent than the parent compound in the dual luciferase ternary complex reporter assay, activate downstream effectors of reduced ternary complex abundance, and inhibit cancer cell proliferation in the low µM range. Moreover, some of these compounds are decorated with substituents that are known to endow favorable physicochemical properties and as such are good candidates for evaluation in animal models of human cancer.