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1.
Cell ; 151(2): 289-303, 2012 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-23021777

RESUMO

Th17 cells have critical roles in mucosal defense and are major contributors to inflammatory disease. Their differentiation requires the nuclear hormone receptor RORγt working with multiple other essential transcription factors (TFs). We have used an iterative systems approach, combining genome-wide TF occupancy, expression profiling of TF mutants, and expression time series to delineate the Th17 global transcriptional regulatory network. We find that cooperatively bound BATF and IRF4 contribute to initial chromatin accessibility and, with STAT3, initiate a transcriptional program that is then globally tuned by the lineage-specifying TF RORγt, which plays a focal deterministic role at key loci. Integration of multiple data sets allowed inference of an accurate predictive model that we computationally and experimentally validated, identifying multiple new Th17 regulators, including Fosl2, a key determinant of cellular plasticity. This interconnected network can be used to investigate new therapeutic approaches to manipulate Th17 functions in the setting of inflammatory disease.


Assuntos
Redes Reguladoras de Genes , Células Th17/citologia , Células Th17/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Diferenciação Celular , Encefalomielite Autoimune Experimental/imunologia , Antígeno 2 Relacionado a Fos/imunologia , Antígeno 2 Relacionado a Fos/metabolismo , Estudo de Associação Genômica Ampla , Humanos , Fatores Reguladores de Interferon/metabolismo , Camundongos , Camundongos Knockout , Dados de Sequência Molecular , Membro 3 do Grupo F da Subfamília 1 de Receptores Nucleares/metabolismo , Células Th17/imunologia
2.
Blood ; 142(22): 1871-1878, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-37494698

RESUMO

Most patients with solitary bone plasmacytomas (SBP) progress to multiple myeloma (MM) after definitive radiation therapy as their primary treatment. Whether the presence of high-risk (HR) cytogenetic abnormalities by fluorescence in situ hybridization (FISH) in the clonal plasma cells, obtained either directly from the diagnostic SBP tissue or the corresponding bone marrow examination at the time of diagnosis, is associated with a shorter time to progression (TTP) to MM is unknown. This study evaluated all patients diagnosed with SBP at the Mayo Clinic from January 2012 to July 2022. The presence of del(17p), t(14;16), t(4;14), or +1q (gain or amplification) by FISH in clonal plasma cells was defined as HR. A total of 114 patients were included in this cohort, and baseline FISH was available for 55 patients (48%), of which 22 were classified as HR (40%). The median TTP to MM for patients with SBP and HR FISH was 8 months (95% confidence interval [CI], 6.3-26) compared with 42 months (95% CI, 25-not reached [NR]) in patients with SBP without HR FISH (P < .001). In a multivariate analysis, only HR FISH was a significant predictor for shorter TTP to MM, independent of minimal marrow involvement and an abnormal serum free light chain ratio at diagnosis. Deletion (17p) and gain 1q abnormalities were the most common FISH abnormalities responsible for the short TTP to MM. Thus, assessing for HR FISH abnormalities in clonal plasma cells derived from either the diagnostic SBP tissue or the staging bone marrow examination of patients with newly diagnosed SBP is feasible and prognostic for a shorter TTP to MM.


Assuntos
Mieloma Múltiplo , Plasmocitoma , Humanos , Plasmocitoma/genética , Hibridização in Situ Fluorescente , Aberrações Cromossômicas , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/genética , Prognóstico , Progressão da Doença
3.
J Biol Chem ; 299(4): 103032, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36806682

RESUMO

The human oxysterol 12α-hydroxylase cytochrome P450 8B1 (CYP8B1) is a validated drug target for both type 2 diabetes and nonalcoholic fatty liver disease, but effective selective inhibitors are not yet available. Herein, steroidal substrate-mimicking compounds with a pyridine ring appended to the C12 site of metabolism were designed as inhibitors, synthesized, and evaluated in terms of their functional and structural interactions with CYP8B1. While the pyridine nitrogen was intended to coordinate the CYP8B1 active site heme iron, none of these compounds elicited shifts in the CYP8B1 Soret absorbance consistent with this type of interaction. However, when CYP8B1 was cocrystallized with the pyridine-containing compound with the 3-keto-Δ4 steroid backbone most similar to the endogenous substrate, it was apparent that this ligand was bound in a channel leading to the active site, instead of near the heme iron. Inspection of this structure suggested that tryptophan 281 directly above the heme might restrict active site binding of potential inhibitors with this design. This hypothesis was supported when a CYP8B1 W281F mutation did allow all three compounds to coordinate the heme iron as designed. These results indicated that the design of next-generation CYP8B1 inhibitors should be compatible with the low-ceiling tryptophan immediately above the heme iron.


Assuntos
Diabetes Mellitus Tipo 2 , Esteroide 12-alfa-Hidroxilase , Humanos , Esteroide 12-alfa-Hidroxilase/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Domínio Catalítico , Triptofano , Esteroides , Piridinas/farmacologia , Heme/metabolismo , Ferro/metabolismo
4.
Artigo em Inglês | MEDLINE | ID: mdl-38908733

RESUMO

BACKGROUND & AIMS: Post-acute COVID-19 syndrome (PACS) is associated with sleep disturbance but treatment options are limited. The aetiology of PACS may be secondary to alterations in the gut microbiome. Here, we report the efficacy of faecal microbiota transplantation (FMT) in alleviating post-COVID insomnia symptoms in a non-randomised, open-label prospective interventional study. METHODS: Between September 22, 2022 and May 22, 2023, we recruited 60 PACS patients with insomnia defined as Insomnia Severity Index (ISI) ≥ 8 and assigned them to the FMT group (FMT at weeks 0, 2, 4 and 8; n=30) or the control group (n=30). The primary outcome was clinical remission defined by an ISI of less than eight at 12 weeks. Secondary outcomes included changes in the Pittsburgh Sleep Quality Index (PSQI), Generalised Anxiety Disorder-7 scale (GAD-7), Epworth Sleepiness Scale (ESS), Multidimensional Fatigue Inventory (MFI), blood cortisol and melatonin, and gut microbiome analysis on metagenomic sequencing. RESULTS: At week 12, more patients in the FMT than the control group had insomnia remission (37.9% vs 10.0%; p=0.018). The FMT group showed a decrease in ISI score (p<0.0001), PSQI (p<0.0001), GAD-7 (p=0.0019), ESS (p=0.0057) and blood cortisol concentration (p=0.035) from baseline to week 12, but there was no significant change in the control group. There was enrichment of bacteria such as Gemmiger formicilis and depletion of microbial pathways producing menaquinol derivatives after FMT. Gut microbiome profile resembled that of the donor in FMT responders but not in non-responders at week 12. There was no serious adverse event. CONCLUSION: This pilot study showed that FMT could be effective and safe in alleviating post-COVID insomnia and further clinical trials are warranted. CLINICALTRIALS: gov identifier: NCT05556733.

5.
Clin Gastroenterol Hepatol ; 22(3): 630-641.e4, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37918685

RESUMO

BACKGROUND: The effect of computer-aided polyp detection (CADe) on adenoma detection rate (ADR) among endoscopists-in-training remains unknown. METHODS: We performed a single-blind, parallel-group, randomized controlled trial in Hong Kong between April 2021 and July 2022 (NCT04838951). Eligible subjects undergoing screening/surveillance/diagnostic colonoscopies were randomized 1:1 to receive colonoscopies with CADe (ENDO-AID[OIP-1]) or not (control) during withdrawal. Procedures were performed by endoscopists-in-training with <500 procedures and <3 years' experience. Randomization was stratified by patient age, sex, and endoscopist experience (beginner vs intermediate level, <200 vs 200-500 procedures). Image enhancement and distal attachment devices were disallowed. Subjects with incomplete colonoscopies or inadequate bowel preparation were excluded. Treatment allocation was blinded to outcome assessors. The primary outcome was ADR. Secondary outcomes were ADR for different adenoma sizes and locations, mean number of adenomas, and non-neoplastic resection rate. RESULTS: A total of 386 and 380 subjects were randomized to CADe and control groups, respectively. The overall ADR was significantly higher in the CADe group than in the control group (57.5% vs 44.5%; adjusted relative risk, 1.41; 95% CI, 1.17-1.72; P < .001). The ADRs for <5 mm (40.4% vs 25.0%) and 5- to 10-mm adenomas (36.8% vs 29.2%) were higher in the CADe group. The ADRs were higher in the CADe group in both the right colon (42.0% vs 30.8%) and left colon (34.5% vs 27.6%), but there was no significant difference in advanced ADR. The ADRs were higher in the CADe group among beginner (60.0% vs 41.9%) and intermediate-level (56.5% vs 45.5%) endoscopists. Mean number of adenomas (1.48 vs 0.86) and non-neoplastic resection rate (52.1% vs 35.0%) were higher in the CADe group. CONCLUSIONS: Among endoscopists-in-training, the use of CADe during colonoscopies was associated with increased overall ADR. (ClinicalTrials.gov, Number: NCT04838951).


Assuntos
Adenoma , Pólipos do Colo , Neoplasias Colorretais , Pólipos , Humanos , Neoplasias Colorretais/diagnóstico , Método Simples-Cego , Colonoscopia/métodos , Adenoma/diagnóstico , Computadores , Pólipos do Colo/diagnóstico
6.
Anticancer Drugs ; 35(1): 63-69, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37067996

RESUMO

Daratumumab is an anti-CD38 mAb, used frequently in combination with lenalidomide and pomalidomide. No studies compared daratumumab plus lenalidomide and dexamethasone (DRd) to daratumumab plus pomalidomide and dexamethasone (DPd) in lenalidomide-exposed multiple myeloma. We identified 504 consecutive multiple myeloma patients who received daratumumab at Mayo Clinic between January 2015 and April 2019. We excluded patients who received daratumumab in the first line, received more than four lines of therapy prior to daratumumab use, did not receive lenalidomide prior to daratumumab, or had an unknown status of lenalidomide exposure, and patients who received daratumumab combinations other than DRd or DPd. We examined the impact of using DRd compared to DPd on progression-free survival (PFS) and overall survival (OS) in patients with relapsed/refractory multiple myeloma. Out of 504 patients, 162 received DRd or DPd and were included; 67 were lenalidomide-exposed and 95 were lenalidomide-refractory. DRd was used in 76 (47%) and DPd in 86 (53%) patients. In lenalidomide-exposed multiple myeloma, there was no difference in median PFS; 34.2 months [95% confidence interval (CI), 22.8-44.6] for DRd compared to 25.2 months (95% CI, 4.9-35.3) for DPd, P  = 0.2. In lenalidomide-refractory multiple myeloma, there was no difference in median PFS; 18.6 months (95% CI, 13-32) for DRd compared to 9 months (95% CI, 5.2-14.6) for DPd, P  = 0.09. No difference in median OS was observed in DRd compared to DPd. Our study shows combining daratumumab with lenalidomide in patients with prior lenalidomide use is a viable and effective treatment option.


Assuntos
Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , Lenalidomida/uso terapêutico , Dexametasona/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
7.
Biometrics ; 80(1)2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38364807

RESUMO

When building regression models for multivariate abundance data in ecology, it is important to allow for the fact that the species are correlated with each other. Moreover, there is often evidence species exhibit some degree of homogeneity in their responses to each environmental predictor, and that most species are informed by only a subset of predictors. We propose a generalized estimating equation (GEE) approach for simultaneous homogeneity pursuit (ie, grouping species with similar coefficient values while allowing differing groups for different covariates) and variable selection in regression models for multivariate abundance data. Using GEEs allows us to straightforwardly account for between-response correlations through a (reduced-rank) working correlation matrix. We augment the GEE with both adaptive fused lasso- and adaptive lasso-type penalties, which aim to cluster the species-specific coefficients within each covariate and encourage differing levels of sparsity across the covariates, respectively. Numerical studies demonstrate the strong finite sample performance of the proposed method relative to several existing approaches for modeling multivariate abundance data. Applying the proposed method to presence-absence records collected along the Great Barrier Reef in Australia reveals both a substantial degree of homogeneity and sparsity in species-environmental relationships. We show this leads to a more parsimonious model for understanding the environmental drivers of seabed biodiversity, and results in stronger out-of-sample predictive performance relative to methods that do not accommodate such features.

8.
Digestion ; 105(1): 62-68, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37497916

RESUMO

INTRODUCTION: Diagnostic and therapeutic methods for colorectal cancer (CRC) have advanced; however, they may be inaccessible worldwide, and their widespread use is challenging. This questionnaire survey investigates the current status of diagnosis and treatment of early-stage CRC in Asian countries. METHODS: Responses to the questionnaire were obtained from 213 doctors at different institutions in 8 countries and regions. The questionnaire consisted of 39 questions on the following four topics: noninvasive diagnosis other than endoscopy (6 questions), diagnosis by magnification and image-enhanced endoscopy (IEE) including artificial intelligence (AI) (10 questions), endoscopic submucosal dissection (ESD), proper use among other therapeutic methods (11 questions), and pathologic diagnosis and surveillance (12 questions). RESULTS: Although 101 of 213 respondents were affiliated with academic hospitals, there were disparities among countries and regions in the dissemination of advanced technologies, such as IEE, AI, and ESD. The NICE classification is widely used for the diagnosis of colorectal tumors using IEE, while the JNET classification with magnification was used in countries such as Japan (65/70, 92.9%) and China (16/22, 72.7%). Of the 211 respondents, 208 (98.6%) assumed that en bloc resection should be achieved for carcinomas, and 180 of 212 (84.9%) believed that ESD was the most suitable in cases with a diameter larger than 2 cm. However, colorectal ESD is not widespread in countries such as Thailand, the Philippines, and Indonesia. CONCLUSION: The promotion of advanced technologies and education should be continual to enable more people to benefit from them.


Assuntos
Neoplasias Colorretais , Ressecção Endoscópica de Mucosa , Humanos , Inteligência Artificial , Dissecação/métodos , Endoscopia Gastrointestinal/métodos , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/cirurgia , Ressecção Endoscópica de Mucosa/métodos , Inquéritos e Questionários , Resultado do Tratamento , Mucosa Intestinal/patologia , Colonoscopia , Estudos Retrospectivos
9.
Ann Intern Med ; 176(4): 455-462, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36877964

RESUMO

BACKGROUND: Current endoscopic methods in the control of acute nonvariceal bleeding have a small but clinically significant failure rate. The role of over-the-scope clips (OTSCs) as the first treatment has not been defined. OBJECTIVE: To compare OTSCs with standard endoscopic hemostatic treatments in the control of bleeding from nonvariceal upper gastrointestinal causes. DESIGN: A multicenter, randomized controlled trial. (ClinicalTrials.gov: NCT03216395). SETTING: University teaching hospitals in Hong Kong, China, and Australia. PATIENTS: 190 adult patients with active bleeding or a nonbleeding visible vessel from a nonvariceal cause on upper gastrointestinal endoscopy. INTERVENTION: Standard hemostatic treatment (n = 97) or OTSC (n = 93). MEASUREMENTS: The primary outcome was 30-day probability of further bleeds. Other outcomes included failure to control bleeding after assigned endoscopic treatment, recurrent bleeding after initial hemostasis, further intervention, blood transfusion, and hospitalization. RESULTS: The 30-day probability of further bleeding in the standard treatment and OTSC groups was 14.6% (14 of 97) and 3.2% (3 of 93), respectively (risk difference, 11.4 percentage points [95% CI, 3.3 to 20.0 percentage points]; P = 0.006). Failure to control bleeding after assigned endoscopic treatment in the standard treatment and OTSC groups was 6 versus 1 (risk difference, 5.1 percentage points [CI, 0.7 to 11.8 percentage points]), respectively, and 30-day recurrent bleeding was 8 versus 2 (risk difference, 6.6 percentage points [CI, -0.3 to 14.4 percentage points]), respectively. The need for further interventions was 8 versus 2, respectively. Thirty-day mortality was 4 versus 2, respectively. In a post hoc analysis with a composite end point of failure to successfully apply assigned treatment and further bleeds, the event rate was 15 of 97 (15.6%) and 6 of 93 (6.5%) in the standard and OTSC groups, respectively (risk difference, 9.1 percentage points [CI, 0.004 to 18.3 percentage points]). LIMITATION: Clinicians were not blinded to treatment and the option of crossover treatment. CONCLUSION: Over-the-scope clips, as an initial treatment, may be better than standard treatment in reducing the risk for further bleeding from nonvariceal upper gastrointestinal causes that are amenable to OTSC placement. PRIMARY FUNDING SOURCE: General Research Fund to the University Grant Committee, Hong Kong SAR Government.


Assuntos
Hemorragia Gastrointestinal , Hemostase Endoscópica , Adulto , Humanos , Hemorragia Gastrointestinal/etiologia , Hemorragia Gastrointestinal/cirurgia , Hemostase Endoscópica/efeitos adversos , Hemostase Endoscópica/métodos , Resultado do Tratamento , Austrália , China , Endoscopia Gastrointestinal/efeitos adversos
10.
Skeletal Radiol ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937291

RESUMO

OBJECTIVE: To develop a whole-body low-dose CT (WBLDCT) deep learning model and determine its accuracy in predicting the presence of cytogenetic abnormalities in multiple myeloma (MM). MATERIALS AND METHODS: WBLDCTs of MM patients performed within a year of diagnosis were included. Cytogenetic assessments of clonal plasma cells via fluorescent in situ hybridization (FISH) were used to risk-stratify patients as high-risk (HR) or standard-risk (SR). Presence of any of del(17p), t(14;16), t(4;14), and t(14;20) on FISH was defined as HR. The dataset was evenly divided into five groups (folds) at the individual patient level for model training. Mean and standard deviation (SD) of the area under the receiver operating curve (AUROC) across the folds were recorded. RESULTS: One hundred fifty-one patients with MM were included in the study. The model performed best for t(4;14), mean (SD) AUROC of 0.874 (0.073). The lowest AUROC was observed for trisomies: AUROC of 0.717 (0.058). Two- and 5-year survival rates for HR cytogenetics were 87% and 71%, respectively, compared to 91% and 79% for SR cytogenetics. Survival predictions by the WBLDCT deep learning model revealed 2- and 5-year survival rates for patients with HR cytogenetics as 87% and 71%, respectively, compared to 92% and 81% for SR cytogenetics. CONCLUSION: A deep learning model trained on WBLDCT scans predicted the presence of cytogenetic abnormalities used for risk stratification in MM. Assessment of the model's performance revealed good to excellent classification of the various cytogenetic abnormalities.

11.
J Esthet Restor Dent ; 36(4): 620-631, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37950565

RESUMO

OBJECTIVE: Obtaining strong resin bonds to computer-aided design and computer-aided manufacturing (CAD-CAM) resin-based composites with dispersed fillers (CCRBCs) poses a challenge. Therefore, this study aimed to assess the effect of three universal adhesives and a two-component silane coupling agent on the shear bond strength to three (CCRBCs). MATERIALS AND METHODS: Eight hundred and sixty-four specimens of Brilliant Crios, Lava Ultimate, and Tetric CAD were polished or grit blasted, bonded with Adhese Universal DC, One Coat 7 Universal (OC7), and Scotchbond Universal Plus Adhesive (SBU) with or without a silane primer. Shear bond strength was measured after 24 h and 10,000 thermocycles. Linear regressions were performed (α = 0.05). RESULTS: After thermocycling, bond strengths were similar for the universal adhesives on polished Brilliant Crios and Lava Ultimate (p ≥ 0.408). Grit blasted Tetric CAD showed no significant differences (p ≥ 0.096). The silane primer had minimal impact on grit blasted Tetric CAD (p ≥ 0.384). The silane primer increased the bond strength of OC7 to Brilliant Crios (p = 0.001) but decreased the adhesion of SBU to Brilliant Crios and Lava Ultimate (p ≤ 0.018). CONCLUSIONS: Bond strength of universal adhesives varied with CCRBC type. The two-component silane coupling agent showed mixed effects on adhesive performance. CLINICAL SIGNIFICANCE: Selecting universal adhesives from the same CCRBC product line does not always guarantee superior bond strength. The efficacy of silane coupling agents differs based on the bonding substrate.


Assuntos
Colagem Dentária , Silanos , Silanos/química , Cimentos Dentários , Propriedades de Superfície , Materiais Dentários , Cimentos de Resina/química , Desenho Assistido por Computador , Teste de Materiais
12.
Angew Chem Int Ed Engl ; : e202406542, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38820076

RESUMO

Cytochrome P450 (P450, CYP) 19A1 is the steroid aromatase, the enzyme responsible for the 3-step conversion of androgens (androstenedione or testosterone) to estrogens. The final step is C-C bond scission (removing the 19-oxo group as formic acid) that proceeds via a historically controversial reaction mechanism. The two competing mechanistic possibilities involve a ferric peroxide anion (Fe3+O2-, Compound 0) and a perferryl oxy species (FeO3+, Compound I). One approach to discern the role of each species in the reaction is with the use of oxygen-18 labeling, i.e., from 18O2 and H218O of the reaction product formic acid. We applied this approach, using several technical improvements, to study the deformylation of 19-oxo-androstenedione by human P450 19A1 and of a model secosteroid, 3-oxodecaline-4-ene-10-carboxaldehyde (ODEC), by rabbit P450 2B4. Both aldehyde substrates were sensitive to non-enzymatic acid-catalyzed deformylation, yielding 19-norsteroids, and conditions were established to avoid issues with artifactual generation of formic acid. The Compound 0 reaction pathway predominated (i.e., Fe3+O2-) in both P450 19A1 oxidation of 19-oxo-androstenedione and P450 2B4 oxidation of ODEC. The P450 19A1 results contrast with our prior conclusions (J. Am. Chem. Soc. 2014, 136, 15016-16025), attributed to several technical modifications.

13.
Gut ; 72(7): 1240-1254, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37019620

RESUMO

Screening for colorectal cancer (CRC) is effective in reducing CRC related mortality. Current screening methods include endoscopy based and biomarker based approaches. This guideline is a joint official statement of the Asian Pacific Association of Gastroenterology (APAGE) and the Asian Pacific Society of Digestive Endoscopy (APSDE), developed in response to the increasing use of, and accumulating supportive evidence for the role of, non-invasive biomarkers for the diagnosis of CRC and its precursor lesions. A systematic review of 678 publications and a two stage Delphi consensus process involving 16 clinicians in various disciplines was undertaken to develop 32 evidence based and expert opinion based recommendations for the use of faecal immunochemical tests, faecal based tumour biomarkers or microbial biomarkers, and blood based tumour biomarkers for the detection of CRC and adenoma. Comprehensive up-to-date guidance is provided on indications, patient selection and strengths and limitations of each screening tool. Future research to inform clinical applications are discussed alongside objective measurement of research priorities. This joint APAGE-APSDE practice guideline is intended to provide an up-to-date guide to assist clinicians worldwide in utilising non-invasive biomarkers for CRC screening; it has particular salience for clinicians in the Asia-Pacific region.


Assuntos
Neoplasias Colorretais , Gastroenterologia , Humanos , Endoscopia Gastrointestinal , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/prevenção & controle , Fezes , Biomarcadores Tumorais , Detecção Precoce de Câncer
14.
J Biol Chem ; 298(10): 102394, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988652

RESUMO

Exosomes are small extracellular vesicles of ∼30 to 150 nm that are secreted by all cells, abundant in all biofluids, and play important roles in health and disease. However, details about the mechanism of exosome biogenesis are unclear. Here, we carried out a cargo-based analysis of exosome cargo protein biogenesis in which we identified the most highly enriched exosomal cargo proteins and then followed their biogenesis, trafficking, and exosomal secretion to test different hypotheses for how cells make exosomes. We show that exosome cargo proteins bud from cells (i) in exosome-sized vesicles regardless of whether they are localized to plasma or endosome membranes, (ii) ∼5-fold more efficiently when localized to the plasma membrane, (iii) ∼5-fold less efficiently when targeted to the endosome membrane, (iv) by a stochastic process that leads to ∼100-fold differences in their abundance from one exosome to another, and (v) independently of small GTPase Rab27a, the ESCRT complex-associated protein Alix, or the cargo protein CD63. Taken together, our results demonstrate that cells use a shared, stochastic mechanism to bud exosome cargoes along the spectrum of plasma and endosome membranes and far more efficiently from the plasma membrane than the endosome. Our observations also indicate that the pronounced variation in content between different exosome-sized vesicles is an inevitable consequence of a stochastic mechanism of small vesicle biogenesis, that the origin membrane of exosome-sized extracellular vesicles simply cannot be determined, and that most of what we currently know about exosomes has likely come from studies of plasma membrane-derived vesicles.


Assuntos
Exossomos , Proteínas de Transporte Vesicular , Endossomos/metabolismo , Exossomos/metabolismo , Membranas Intracelulares/metabolismo , Humanos , Proteínas de Transporte Vesicular/metabolismo
15.
Cancer ; 129(3): 385-392, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36413412

RESUMO

BACKGROUND: Sarcopenia increases with age and is associated with poor survival outcomes in patients with cancer. By using a deep learning-based segmentation approach, clinical computed tomography (CT) images of the abdomen of patients with newly diagnosed multiple myeloma (NDMM) were reviewed to determine whether the presence of sarcopenia had any prognostic value. METHODS: Sarcopenia was detected by accurate segmentation and measurement of the skeletal muscle components present at the level of the L3 vertebrae. These skeletal muscle measurements were further normalized by the height of the patient to obtain the skeletal muscle index for each patient to classify them as sarcopenic or not. RESULTS: The study cohort consisted of 322 patients of which 67 (28%) were categorized as having high risk (HR) fluorescence in situ hybridization (FISH) cytogenetics. A total of 171 (53%) patients were sarcopenic based on their peri-diagnosis standard-dose CT scan. The median overall survival (OS) and 2-year mortality rate for sarcopenic patients was 44 months and 40% compared to 90 months and 18% for those not sarcopenic, respectively (p < .0001 for both comparisons). In a multivariable model, the adverse prognostic impact of sarcopenia was independent of International Staging System stage, age, and HR FISH cytogenetics. CONCLUSIONS: Sarcopenia identified by a machine learning-based convolutional neural network algorithm significantly affects OS in patients with NDMM. Future studies using this machine learning-based methodology of assessing sarcopenia in larger prospective clinical trials are required to validate these findings.


Assuntos
Aprendizado Profundo , Mieloma Múltiplo , Sarcopenia , Humanos , Sarcopenia/complicações , Sarcopenia/diagnóstico por imagem , Mieloma Múltiplo/complicações , Mieloma Múltiplo/diagnóstico por imagem , Mieloma Múltiplo/patologia , Estudos Prospectivos , Hibridização in Situ Fluorescente , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Músculo Esquelético/diagnóstico por imagem , Prognóstico
16.
N Engl J Med ; 382(14): 1299-1308, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242355

RESUMO

BACKGROUND: It is recommended that patients with acute upper gastrointestinal bleeding undergo endoscopy within 24 hours after gastroenterologic consultation. The role of endoscopy performed within time frames shorter than 24 hours has not been adequately defined. METHODS: To evaluate whether urgent endoscopy improves outcomes in patients predicted to be at high risk for further bleeding or death, we randomly assigned patients with overt signs of acute upper gastrointestinal bleeding and a Glasgow-Blatchford score of 12 or higher (scores range from 0 to 23, with higher scores indicating a higher risk of further bleeding or death) to undergo endoscopy within 6 hours (urgent-endoscopy group) or between 6 and 24 hours (early-endoscopy group) after gastroenterologic consultation. The primary end point was death from any cause within 30 days after randomization. RESULTS: A total of 516 patients were enrolled. The 30-day mortality was 8.9% (23 of 258 patients) in the urgent-endoscopy group and 6.6% (17 of 258) in the early-endoscopy group (difference, 2.3 percentage points; 95% confidence interval [CI], -2.3 to 6.9). Further bleeding within 30 days occurred in 28 patients (10.9%) in the urgent-endoscopy group and in 20 (7.8%) in the early-endoscopy group (difference, 3.1 percentage points; 95% CI, -1.9 to 8.1). Ulcers with active bleeding or visible vessels were found on initial endoscopy in 105 of the 158 patients (66.4%) with peptic ulcers in the urgent-endoscopy group and in 76 of 159 (47.8%) in the early-endoscopy group. Endoscopic hemostatic treatment was administered at initial endoscopy for 155 patients (60.1%) in the urgent-endoscopy group and for 125 (48.4%) in the early-endoscopy group. CONCLUSIONS: In patients with acute upper gastrointestinal bleeding who were at high risk for further bleeding or death, endoscopy performed within 6 hours after gastroenterologic consultation was not associated with lower 30-day mortality than endoscopy performed between 6 and 24 hours after consultation. (Funded by the Health and Medical Fund of the Food and Health Bureau, Government of Hong Kong Special Administrative Region; ClinicalTrials.gov number, NCT01675856.).


Assuntos
Endoscopia Gastrointestinal , Varizes Esofágicas e Gástricas/diagnóstico , Hemorragia Gastrointestinal/diagnóstico , Úlcera Péptica Hemorrágica/diagnóstico , Doença Aguda , Idoso , Varizes Esofágicas e Gástricas/terapia , Feminino , Hemorragia Gastrointestinal/mortalidade , Hemorragia Gastrointestinal/terapia , Hospitalização , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Úlcera Péptica Hemorrágica/mortalidade , Úlcera Péptica Hemorrágica/terapia , Medição de Risco , Fatores de Tempo , Tempo para o Tratamento
17.
Gastroenterology ; 162(2): 548-561.e4, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34687739

RESUMO

BACKGROUND AND AIMS: Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with altered gut microbiota composition. Phylogenetic groups of gut bacteria involved in the metabolism of short chain fatty acids (SCFAs) were depleted in SARS-CoV-2-infected patients. We aimed to characterize a functional profile of the gut microbiome in patients with COVID-19 before and after disease resolution. METHODS: We performed shotgun metagenomic sequencing on fecal samples from 66 antibiotics-naïve patients with COVID-19 and 70 non-COVID-19 controls. Serial fecal samples were collected (at up to 6 times points) during hospitalization and beyond 1 month after discharge. We assessed gut microbial pathways in association with disease severity and blood inflammatory markers. We also determined changes of microbial functions in fecal samples before and after disease resolution and validated these functions using targeted analysis of fecal metabolites. RESULTS: Compared with non-COVID-19 controls, patients with COVID-19 with severe/critical illness showed significant alterations in gut microbiome functionality (P < .001), characterized by impaired capacity of gut microbiome for SCFA and L-isoleucine biosynthesis and enhanced capacity for urea production. Impaired SCFA and L-isoleucine biosynthesis in gut microbiome persisted beyond 30 days after recovery in patients with COVID-19. Targeted analysis of fecal metabolites showed significantly lower fecal concentrations of SCFAs and L-isoleucine in patients with COVID-19 before and after disease resolution. Lack of SCFA and L-isoleucine biosynthesis significantly correlated with disease severity and increased plasma concentrations of CXCL-10, NT- proB-type natriuretic peptide, and C-reactive protein (all P < .05). CONCLUSIONS: Gut microbiome of patients with COVID-19 displayed impaired capacity for SCFA and L-isoleucine biosynthesis that persisted even after disease resolution. These 2 microbial functions correlated with host immune response underscoring the importance of gut microbial functions in SARS-CoV-2 infection pathogenesis and outcome.


Assuntos
COVID-19/microbiologia , Ácidos Graxos Voláteis/biossíntese , Microbioma Gastrointestinal/genética , Imunidade/fisiologia , Isoleucina/biossíntese , Adulto , Biomarcadores/sangue , Estudos de Casos e Controles , Fezes/microbiologia , Feminino , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade , Filogenia , SARS-CoV-2 , Índice de Gravidade de Doença
18.
Virol J ; 20(1): 279, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38031075

RESUMO

INTRODUCTION: Viral load assessment for people living with HIV is key for monitoring treatment and achieving the 95-95-95. In this study, we aimed to assess the degree of viral suppression at different thresholds and treatment duration after the introduction of dolutegravir-based therapy in ten public hospitals in Sierra Leone. METHODS: We used a cross-sectional study design to recruits patients aged 18 years or older between August 2022 and January 2023. Statistical analyses were performed using R-software. Logistic regression was used to assess factors independently associated with viral suppression. The level of significance was set at P < 0.05. RESULTS: Of the 2,253 patients recruited, 1,720 (76%) were women and 1,705 (76%) were receiving a fixed dose combination of tenofovir, lamivudine and dolutegravir. The median age and duration of anti-retroviral therapy (ART) was 36.0 (IQR, 28.0-45.0) years and 40.9 (IQR, 14.4-79.6) months, respectively. Using a threshold of HIV RNA < 1000 copies/mL, 1,715 (88.4%) patients on ART for more than 6 months were virally suppressed. Viral suppression rates were higher with dolutegravir-based (1,277, 89.5%) than efavirenz-based (418, 86.2%) ART. HIV RNA was < 200 copies/mL in 1,643 (84.6%) patients or < 50 copies/mL in 1,487 (76.6%) patients or between 50 and 999 copies/mL in 228 (11.7%) patients. Viral suppression rates at different ART durations (months) were as follows: 84.2% (≤ 3), 88.8% (4-6), 90.9% (6-12), and 88.1% (> 12). Viral suppression rates were higher for patients aged 40 or older (40-50 years: aOR 2.05, 95%CI 1.41-3.04, P < 0.01; 50-60 years: aOR 2.51, 95%CI 1.53-4.35, P < 0.01; >60 years: aOR 2.69, 95%CI 1.28-6.63, P = 0.02). Men had 49% lower odds of viral suppression than women (aOR 0.50, 95% CI 0.38-0.67, P < 0.01). CONCLUSION: We report a viral suppression rate of 88.4% among patients on treatment for at least 6 months, with higher rate of suppression with dolutegravir than efavirenz. Factors associated with virological suppression were age and gender, emphasizing the need for innovative differentiated ART delivery models to optimize viral suppression and achieve the 95% target.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Masculino , Humanos , Feminino , Duração da Terapia , Serra Leoa , Estudos Transversais , Benzoxazinas/efeitos adversos , Oxazinas/uso terapêutico , Infecções por HIV/tratamento farmacológico , RNA , Carga Viral , Fármacos Anti-HIV/uso terapêutico
19.
Gastrointest Endosc ; 97(3): 517-527.e1, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36209766

RESUMO

BACKGROUND AND AIMS: Antithrombotic use is a significant risk factor of postpolypectomy bleeding (PPB). Evidence of prophylactic clipping is only available for proximal and large colonic lesions in the general population. Dedicated studies to examine the benefit of prophylactic clipping in patients on aspirin remain scarce. METHODS: A propensity score-weighted retrospective cohort study was performed in a tertiary referral center from January 2018 to September 2021. Patients who received aspirin and underwent colonoscopic polypectomy, EMR, or endoscopic submucosal dissection were included. Data on baseline demographics, medications, and endoscopic factors (polyp number, size, location, and morphology; resection method; and prophylactic clipping) were captured. Propensity score-weighted models were developed between prophylactic clipping and no clipping groups. The primary outcome was delayed PPB within 30 days, with a composite endpoint consisting of repeated colonoscopy for hemostasis, requirement of blood transfusion, or hemoglobin drop >2 g/dL. RESULTS: A total of 1373 patients with 3952 polyps were included. Baseline characteristics were balanced between the 2 groups. In the multivariate analysis, the largest polyp size was a significant risk factor for PPB (odds ratio, 1.07; 95% confidence interval, 1.02-1.11; P = .002). Prophylactic clipping was not associated with a reduced risk of PPB (odds ratio, 1.34; 95% confidence interval, .83-2.18; P = .240) and did not show any risk reduction in subgroups with different polyp sizes and locations and endoscopic resection techniques. CONCLUSIONS: Prophylactic clipping was not associated with a lower risk of PPB in aspirin users after endoscopic resection of colorectal polyps. Aspirin use should not be regarded as the only factor for the routine use of prophylactic clips.


Assuntos
Aspirina , Pólipos do Colo , Humanos , Aspirina/uso terapêutico , Pólipos do Colo/patologia , Estudos Retrospectivos , Pontuação de Propensão , Colonoscopia/métodos , Hemorragia Pós-Operatória/epidemiologia , Hemorragia Pós-Operatória/prevenção & controle , Hemorragia Pós-Operatória/etiologia
20.
Eur J Haematol ; 111(2): 318-321, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37209032

RESUMO

Daratumumab is an anti-CD38 antibody that is increasingly incorporated in induction regimens for treating patients with newly diagnosed multiple myeloma (NDMM). Previous reports have demonstrated a lower yield of hematopoietic stem cells (HSCs) after induction with daratumumab; however, none of them reported a failure to collect an adequate number of HSCs. We describe a case of adequate HSC mobilization failure in a patient who inadvertently received excessive doses of daratumumab and was confirmed by higher-than-expected circulating levels of daratumumab by mass spectrometry. Eventual clearance of circulating daratumumab was associated with the successful mobilization and harvesting of HSCs.


Assuntos
Antineoplásicos , Mieloma Múltiplo , Humanos , ADP-Ribosil Ciclase 1/metabolismo , Antineoplásicos/uso terapêutico , Mieloma Múltiplo/diagnóstico , Mieloma Múltiplo/tratamento farmacológico , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/farmacologia , Células-Tronco Hematopoéticas/metabolismo
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