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1.
Nature ; 608(7924): 784-794, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35798028

RESUMO

Cancer relapse after chemotherapy remains a main cause of cancer-related death. Although the relapse is thought to result from the propagation of resident cancer stem cells1, a lack of experimental platforms that enable the prospective analysis of cancer stem cell dynamics with sufficient spatiotemporal resolution has hindered the testing of this hypothesis. Here we develop a live genetic lineage-tracing system that allows the longitudinal tracking of individual cells in xenotransplanted human colorectal cancer organoids, and identify LGR5+ cancer stem cells that exhibit a dormant behaviour in a chemo-naive state. Dormant LGR5+ cells are marked by the expression of p27, and intravital imaging provides direct evidence of the persistence of LGR5+p27+ cells during chemotherapy, followed by clonal expansion. Transcriptome analysis reveals that COL17A1-a cell-adhesion molecule that strengthens hemidesmosomes-is upregulated in dormant LGR5+p27+ cells. Organoids in which COL17A1 is knocked out lose the dormant LGR5+p27+ subpopulation and become sensitive to chemotherapy, which suggests that the cell-matrix interface has a role in the maintenance of dormancy. Chemotherapy disrupts COL17A1 and breaks the dormancy in LGR5+p27+ cells through FAK-YAP activation. Abrogation of YAP signalling prevents chemoresistant cells from exiting dormancy and delays the regrowth of tumours, highlighting the therapeutic potential of YAP inhibition in preventing cancer relapse. These results offer a viable therapeutic approach to overcome the refractoriness of human colorectal cancer to conventional chemotherapy.


Assuntos
Neoplasias do Colo , Células-Tronco Neoplásicas , Autoantígenos/metabolismo , Proteínas de Ciclo Celular/metabolismo , Linhagem da Célula , Proliferação de Células , Rastreamento de Células , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Quinase 1 de Adesão Focal/metabolismo , Perfilação da Expressão Gênica , Xenoenxertos , Humanos , Recidiva Local de Neoplasia/patologia , Células-Tronco Neoplásicas/patologia , Colágenos não Fibrilares/metabolismo , Organoides/metabolismo , Organoides/patologia , Receptores Acoplados a Proteínas G/metabolismo , Fatores de Transcrição/metabolismo , Colágeno Tipo XVII
2.
Nature ; 577(7789): 254-259, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31853059

RESUMO

With ageing, normal human tissues experience an expansion of somatic clones that carry cancer mutations1-7. However, whether such clonal expansion exists in the non-neoplastic intestine remains unknown. Here, using whole-exome sequencing data from 76 clonal human colon organoids, we identify a unique pattern of somatic mutagenesis in the inflamed epithelium of patients with ulcerative colitis. The affected epithelium accumulates somatic mutations in multiple genes that are related to IL-17 signalling-including NFKBIZ, ZC3H12A and PIGR, which are genes that are rarely affected in colon cancer. Targeted sequencing validates the pervasive spread of mutations that are related to IL-17 signalling. Unbiased CRISPR-based knockout screening in colon organoids reveals that the mutations confer resistance to the pro-apoptotic response that is induced by IL-17A. Some of these genetic mutations are known to exacerbate experimental colitis in mice8-11, and somatic mutagenesis in human colon epithelium may be causally linked to the inflammatory process. Our findings highlight a genetic landscape that adapts to a hostile microenvironment, and demonstrate its potential contribution to the pathogenesis of ulcerative colitis.


Assuntos
Colite Ulcerativa/genética , Epitélio/metabolismo , Interleucina-17/genética , Mutação , Colite Ulcerativa/metabolismo , Humanos , Interleucina-17/metabolismo , Fenótipo , Transdução de Sinais
3.
Neurobiol Dis ; 199: 106571, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38901781

RESUMO

Leucine-rich repeat kinase 2 (LRRK2) is the most common gene responsible for familial Parkinson's disease (PD). The gene product of LRRK2 contains multiple protein domains, including armadillo repeat, ankyrin repeat, leucine-rich repeat (LRR), Ras-of-complex (ROC), C-terminal of ROC (COR), kinase, and WD40 domains. In this study, we performed genetic screening of LRRK2 in our PD cohort, detecting sixteen LRRK2 rare variants. Among them, we selected seven variants that are likely to be familial and characterized them in terms of LRRK2 protein function, along with clinical information and one pathological analysis. The seven variants were S1120P and N1221K in the LRR domain; I1339M, S1403R, and V1447M in the ROC domain; and I1658F and D1873H in the COR domain. The kinase activity of the LRRK2 variants N1221K, S1403R, V1447M, and I1658F toward Rab10, a well-known phosphorylation substrate, was higher than that of wild-type LRRK2. LRRK2 D1873H showed enhanced self-association activity, whereas LRRK2 S1403R and D1873H showed reduced microtubule-binding activity. Pathological analysis of a patient with the LRRK2 V1447M variant was also performed, which revealed Lewy pathology in the brainstem. No functional alterations in terms of kinase activity, self-association activity, and microtubule-binding activity were detected in LRRK2 S1120P and I1339M variants. However, the patient with PD carrying LRRK2 S1120P variant also had a heterozygous Glucosylceramidase beta 1 (GBA1) L444P variant. In conclusion, we characterized seven LRRK2 variants potentially associated with PD. Five of the seven variants in different LRRK2 domains exhibited altered properties in kinase activity, self-association, and microtubule-binding activity, suggesting that each domain variant may contribute to disease progression in different ways.

4.
J Pediatr Gastroenterol Nutr ; 79(1): 48-53, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38356291

RESUMO

Neonatal immune regulation transitions from fetal immunity and varies with maturation status, but its role in neonatal cow's milk protein allergy (CMPA) remains unknown. We studied the association between maturation status at birth and neonatal CMPA. Clinical and laboratory data of neonates presenting with CMPA symptoms were retrospectively collected from two tertiary hospitals. Patients were assessed according to gestational age at birth: preterm, late-preterm, and full-term. Fifty-five infants (26 females, 14 preterm, 15 late-preterm, and 26 full-term) were included; 44 were negative for milk-specific immunoglobulin E. Neonatal CMPA was common during moderately premature periods. Preterm infants exhibited longer latency from initial CM exposure to disease onset, lower incidence of bloody stool, and absence of elevated monocyte counts. However, immunoreactivity to CM antigens was retained in all infants. Neonatal CMPA features varied with infant maturation status at birth. Our results improve the understanding of intestinal immunity development, fetal/neonatal immune regulation, and CMPA pathogenesis.


Assuntos
Recém-Nascido Prematuro , Hipersensibilidade a Leite , Proteínas do Leite , Estudos Retrospectivos , Hipersensibilidade a Leite/imunologia , Humanos , Feminino , Recém-Nascido , Masculino , Proteínas do Leite/imunologia , Proteínas do Leite/efeitos adversos , Recém-Nascido Prematuro/imunologia , Idade Gestacional , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Animais , Bovinos
5.
Retina ; 44(4): 652-658, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38064668

RESUMO

PURPOSE: To investigate the 5-year treatment outcomes of retinopathy of prematurity in infants <500 g birth weight and compare laser and anti-vascular endothelial growth factor therapies. METHODS: A multicenter retrospective study comprised 24 eyes of 13 patients treated for Type 1 retinopathy of prematurity, followed for 5 years. Initial treatment was laser and anti-vascular endothelial growth factor in 13 and 11 eyes, respectively. Data collected included sex, birth characteristics, retinopathy of prematurity characteristics at the time of treatment, best-corrected visual acuity (BCVA), spherical equivalent, and astigmatism at 5 years posttreatment. RESULTS: Median BCVA was 0.15 logarithm of the minimum angle of resolution (interquartile range, 0.0-0.5). Snellen BCVA was ≥20/40 in 73% and ≥20/20 in 27% of eyes. Median spherical equivalent was -2.37 (interquartile range, -6.1 to -0.1); 75% had myopia (≤-0.5 D), and 25% had high myopia (≤-6.0 D). Median astigmatism was 1.25 (interquartile range, 0.9-3.0); 46% had ≥1.5 D. Anti-vascular endothelial growth factor-treated eyes showed less myopia ( P < 0.009), with no BCVA or astigmatism difference ( P = 0.997, P = 0.271) compared with laser-treated eyes. CONCLUSION: One-quarter of the eyes exhibited good visual acuity (Snellen BCVA of ≥20/20) 5 years after retinopathy of prematurity treatment. Refractive errors were common. Anti-vascular endothelial growth factor therapy may be superior to laser therapy in myopic refractive error.


Assuntos
Astigmatismo , Miopia , Erros de Refração , Retinopatia da Prematuridade , Recém-Nascido , Lactente , Humanos , Astigmatismo/terapia , Retinopatia da Prematuridade/cirurgia , Estudos Retrospectivos , Fatores de Crescimento Endotelial , Resultado do Tratamento , Fotocoagulação a Laser
6.
Int J Clin Oncol ; 29(7): 985-993, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38598039

RESUMO

BACKGROUND: The clinical importance of positive peritoneal cytology results in patients with pancreatic ductal adenocarcinomas remains controversial. We evaluated the prognosis of these patients and the predictive preoperative risk factors for positive peritoneal cytology results. METHODS: We retrospectively reviewed patients who underwent curative-intent surgery at our institution between May 2010 and June 2020. Preoperative risk factors for positive peritoneal cytology results were identified using logistic regression analysis. A scoring model was constructed using the total number of significant independent predictors for positive peritoneal cytology results. RESULTS: Of 233 patients, 18 (7.7%) had positive peritoneal cytology results. The recurrence-free survival and cancer-specific survival were markedly worse in patients with positive peritoneal cytology results than in those with negative peritoneal cytology results (recurrence-free survival: 6.0 months vs. 16.6 months, p = 0.050; cancer-specific survival: 19.4 months vs. 47.5 months, p = 0.034). Tumor location (odds ratio: 3.760, 95% confidence interval: 1.099-11.818, p = 0.023), tumor size > 25 mm (odds ratio: 3.410, 95% confidence interval: 1.031-11.277, p = 0.046), preoperative serosal invasion (odds ratio: 5.193, 95% confidence interval: 1.099-24.531, p = 0.038), and preoperative carcinoembryonic antigen level > 5.6 ng/mL (odds ratio: 3.816, 95% confidence interval: 1.248-10.667, p = 0.019) were identified as significant independent predictive factors. Our predictive model's optimal cutoff and positive predictive values for positive peritoneal cytology results were 3 and 27.9%, respectively. CONCLUSIONS: The indications for curative-intent surgery should be considered carefully in patients with high-risk factors for positive peritoneal cytology results.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgia , Neoplasias Pancreáticas/mortalidade , Carcinoma Ductal Pancreático/cirurgia , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/mortalidade , Prognóstico , Fatores de Risco , Adulto , Período Pré-Operatório , Idoso de 80 Anos ou mais , Citodiagnóstico/métodos , Peritônio/patologia , Citologia
7.
Allergol Int ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38600019

RESUMO

BACKGROUND: Intestinal bacteria may play a role in the development of food allergies. This study aimed to analyze and compare the gut microbiota of food-allergic children with that of healthy children of the same age. METHODS: Stool samples were collected from one-and-a-half-year-old food-allergic (FA group, n = 29) and healthy controls (HC group, n = 19). A questionnaire was provided to examine the children's birth, dietary, medical, and social histories. The gut microbiota was profiled by 16S rRNA sequencing. Differences in taxonomic composition were assessed using linear discriminant analysis effect size (LEfSe), and microbial functional profiles were predicted with Tax4Fun2. RESULTS: No significant difference in the alpha diversity index between the two groups; however, a negative correlation was observed between the Shannon diversity index and the relative abundance of Bacteroides. A significant difference was observed in beta diversity (permutational multivariate analysis of variance) in the bacterial composition between the FA and HC groups (P < 0.05). The FA group had a higher abundance of Escherichia and Anaeromassilibacillus and a lower abundance of Bacteroides, Oscillibacter, Ruminococcus, Hungateiclostridium and Anaerotaenia than the HC group (LEfSe: linear discriminant analysis score >2). The FA group showed a predicted increase in the expression levels of genes associated with intestinal pathogenicity compared with that in the HC group. CONCLUSIONS: The gut microbiota of food-allergic children has a higher abundance of bacteria involved in intestinal inflammation and a lower abundance of bacteria involved in immune tolerance than that of healthy children. This dysbiosis may also be associated with food allergies.

8.
Diabetologia ; 66(12): 2356-2367, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37750893

RESUMO

AIMS/HYPOTHESIS: Previous studies have suggested that glucose variability may accelerate atherosclerosis progression in people with type 2 diabetes. Current guidelines recommend assessing glycaemic control using continuous glucose monitoring (CGM), which provides a comprehensive glycaemic profile to supplement HbA1c measurement. However, the association between CGM-derived metrics and atherosclerosis progression is not entirely clear. METHODS: This exploratory study used baseline data and data obtained after 104 weeks from an ongoing prospective, multicentre, observational study. Six hundred study participants with type 2 diabetes and no apparent history of symptomatic cardiovascular disease underwent CGM and ultrasonographic atherosclerosis measurements of the carotid arteries, including the intima-media thickness (IMT) and grey-scale median (GSM), at baseline and 104 weeks. Non-invasive ultrasonic tissue characterisation of the carotid artery wall or plaque using the GSM reflects vascular composition. Multivariate regression models were used to analyse the association between CGM-derived indices, mainly time in range (TIR) and CV, and changes in carotid atherosclerosis index values. RESULTS: Over the 104-week study period, there were modest increases in mean IMT (from 0.759±0.153 to 0.773±0.152 mm, p<0.001) and thickened-lesion GSM (from 43.5±19.5 to 53.9±23.5 units, p<0.001), but no significant changes in common carotid artery maximum-IMT (from 1.109±0.442 to 1.116±0.469 mm, p=0.453) or mean GSM (from 48.7±19.3 to 49.8±20.8 units, p=0.092). In a linear regression model with adjustment for possible atherosclerotic risk factors, including HbA1c, TIR and CV at baseline were significantly associated with the annual change in mean GSM (regression coefficient per 10% increase in TIR 0.52; 95% CI 0.06, 0.98; Hochberg-adjusted p value 0.038; regression coefficient per 1% increase in CV -0.12; 95% CI -0.22, -0.02; Hochberg-adjusted p value 0.038). TIR and CV at baseline were also significantly associated with the annual change in thickened-lesion GSM (regression coefficient per 10% increase in TIR 0.95; 95% CI 0.12, 1.79; Hochberg-adjusted p value 0.038; regression coefficient per 1% increase in CV -0.19; 95% CI -0.36, -0.01; Hochberg-adjusted p value 0.038). Participants who achieved target CGM-derived metrics at baseline, as proposed by an international consensus, showed significant annual changes in mean GSM compared with those who did not (0.94±6.88 vs -0.21±6.19 units/year, p=0.007). CONCLUSIONS/INTERPRETATION: TIR and CV were significantly associated with changes in the tissue characteristics of the carotid artery wall. TRIAL REGISTRATION: University Hospital Medical Information Network Clinical Trials Registry, number UMIN000032325.


Assuntos
Aterosclerose , Diabetes Mellitus Tipo 2 , Humanos , Diabetes Mellitus Tipo 2/tratamento farmacológico , Espessura Intima-Media Carotídea , Estudos Prospectivos , Glicemia , Automonitorização da Glicemia , Artérias Carótidas/diagnóstico por imagem , Artéria Carótida Primitiva/diagnóstico por imagem
9.
Curr Issues Mol Biol ; 45(9): 7630-7641, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37754264

RESUMO

To determine the intracellular behavior of p62, a marker of selective autophagy, in oral potentially malignant disorders (OPMDs). This retrospective study includes 70 patients who underwent biopsy or surgical resection and were definitively diagnosed with OPMDs. Immunohistochemical staining for p62, XPO1, p53, and ki67 was performed on all samples and positive cell occupancy was calculated. We statistically investigated the correlation between protein expression in OPMDs and the association between malignant transformation, clinicopathological characteristics, and occupancy. ki67 expression was negatively correlated with p62 expression in the nucleus (p < 0.01) and positively correlated with p62 expression in the cytoplasm (p < 0.01). For malignant transformation, the expression of p62 in the nucleus (p = 0.03) was significantly lower in malignant transformation cases, whereas the expression of p62 in the cytoplasm (p = 0.03) and the aggregation expression (p < 0.01) were significantly higher. Our results suggest that the function of p62 is altered by its subcellular localization. In addition, defects in selective autophagy occur in cases of malignant transformation, suggesting that p62 is a potential biomarker of the risk of malignant transformation of OPMDs.

10.
Gastroenterology ; 163(5): 1391-1406.e24, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35963362

RESUMO

BACKGROUND & AIMS: In the mouse intestinal epithelium, Lgr5+ stem cells are vulnerable to injury, owing to their predominantly cycling nature, and their progenies de-differentiate to replenish the stem cell pool. However, how human colonic stem cells behave in homeostasis and during regeneration remains unknown. METHODS: Transcriptional heterogeneity among colonic epithelial cells was analyzed by means of single-cell RNA sequencing analysis of human and mouse colonic epithelial cells. To trace the fate of human colonic stem or differentiated cells, we generated LGR5-tdTomato, LGR5-iCasase9-tdTomato, LGR5-split-Cre, and KRT20-ERCreER knock-in human colon organoids via genome engineering. p27+ dormant cells were further visualized with the p27-mVenus reporter. To analyze the dynamics of human colonic stem cells in vivo, we orthotopically xenotransplanted fluorescence-labeled human colon organoids into immune-deficient mice. The cell cycle dynamics in xenograft cells were evaluated using 5-ethynyl-2'-deoxyuridine pulse-chase analysis. The clonogenic capacity of slow-cycling human stem cells or differentiated cells was analyzed in the context of homeostasis, LGR5 ablation, and 5-fluorouracil-induced mucosal injury. RESULTS: Single-cell RNA sequencing analysis illuminated the presence of nondividing LGR5+ stem cells in the human colon. Visualization and lineage tracing of slow-cycling LGR5+p27+ cells and orthotopic xenotransplantation validated their homeostatic lineage-forming capability in vivo, which was augmented by 5-FU-induced mucosal damage. Transforming growth factor-ß signaling regulated the quiescent state of LGR5+ cells. Despite the plasticity of differentiated KRT20+ cells, they did not display clonal growth after 5-FU-induced injury, suggesting that occupation of the niche environment by LGR5+p27+ cells prevented neighboring differentiated cells from de-differentiating. CONCLUSIONS: Our results highlight the quiescent nature of human LGR5+ colonic stem cells and their contribution to post-injury regeneration.


Assuntos
Receptores Acoplados a Proteínas G , Células-Tronco , Humanos , Camundongos , Animais , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Células-Tronco/metabolismo , Colo/metabolismo , Mucosa Intestinal/metabolismo , Fluoruracila , Fatores de Crescimento Transformadores/metabolismo
11.
Stat Med ; 42(15): 2711-2727, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37062288

RESUMO

Using a generalized estimating equation (GEE) can lead to a bias in regression coefficients for a small sample or sparse data. The bias-corrected GEE (BCGEE) and penalized GEE (PGEE) were proposed to resolve the small-sample bias. Moreover, the standard sandwich covariance estimator leads to a bias of standard error for small samples; several modified covariance estimators have been proposed to address this issue. We review the modified GEEs and modified covariance estimators, and evaluate their performance in sparse binary data from small-sample longitudinal studies. The simulation results showed that GEE and BCGEE often failed to achieve convergence, whereas the convergence proportion for PGEE was quite high. The bias for the regression coefficients was generally in the ascending order of PGEE < $$ < $$ BCGEE < $$ < $$ GEE. However, PGEE and BCGEE did not sufficiently remove the bias involving 20-30 subjects with unequal exposure levels with a 5% response rate. The coverage probability (CP) of the confidence interval for BCGEE was relatively poor compared with GEE and PGEE. The CP with the sandwich covariance estimator deteriorated regardless of the GEE methods under the small sample size and low response rate, whereas the CP with the modified covariance estimators-such as Morel's method-was relatively acceptable. PGEE will be the reasonable way for analyzing sparse binary data in small-sample studies. Instead of using the standard sandwich covariance estimator, one should always apply the modified covariance estimators for analyzing these data.


Assuntos
Modelos Estatísticos , Humanos , Viés , Simulação por Computador , Tamanho da Amostra , Estudos Longitudinais
12.
Ann Surg Oncol ; 29(6): 3992-4000, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35175454

RESUMO

INTRODUCTION: Denosumab has been shown to be highly effective at suppressing the progression of giant cell tumor of bone (GCTB). However, recent studies have observed a potential increased risk of local recurrence after surgery following the use of denosumab, raising concerns on the use of this agent against GCTB in combination with surgery. METHODS: We retrospectively reviewed the medical records of 234 patients with GCTB who were surgically treated at multiple institutions from 1990 to 2017. Patient background, tumor characteristics, treatment methods, local recurrence-free survival rate, distant metastasis rate, oncologic outcome, and limb function at final follow-up were analyzed and compared between cases treated with and without denosumab. RESULTS: The 3-year local recurrence-free survival rate was significantly lower in patients who underwent preoperative denosumab therapy (35.3%) compared with those treated without denosumab (79.9%) (P < 0.001). Among patients who were preoperatively treated with denosumab, those who had a local recurrence all underwent curettage surgery. CONCLUSIONS: Preoperative denosumab therapy in combination with curettage surgery was significantly associated with an increased risk of local recurrence in Campanacci grade 3 tumors. Our data suggest that clinicians seeing GCTB patients should be aware to this increased risk when planning preoperative denosumab therapy.


Assuntos
Conservadores da Densidade Óssea , Neoplasias Ósseas , Tumor de Células Gigantes do Osso , Conservadores da Densidade Óssea/efeitos adversos , Conservadores da Densidade Óssea/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Curetagem/efeitos adversos , Denosumab/efeitos adversos , Denosumab/uso terapêutico , Tumor de Células Gigantes do Osso/tratamento farmacológico , Tumor de Células Gigantes do Osso/patologia , Tumor de Células Gigantes do Osso/cirurgia , Humanos , Recidiva Local de Neoplasia/patologia , Estudos Retrospectivos
13.
Opt Express ; 30(11): 18628-18637, 2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-36221660

RESUMO

A unique design of our ultracompact microcavity wavelength conversion device exploits the simple principle that the wavelength conversion efficiency is proportional to the square of the electric field amplitude of enhanced pump light in the microcavity, and expands the range of suitable device materials to include crystals that do not exhibit birefringence or ferroelectricity. Here, as a first step toward practical applications of all-solid-state ultracompact deep-ultraviolet coherent light sources, we adopted a low-birefringence paraelectric SrB4O7 crystal with great potential for wavelength conversion and high transparency down to 130 nm as our device material, and demonstrated 234 nm deep-ultraviolet coherent light generation, whose wavelength band is expected to be used for on-demand disinfection tools that can irradiate the human body.

14.
Stat Med ; 41(21): 4130-4142, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-35713225

RESUMO

The adaptive seamless design combining phases II and III into a single trial has been shown growing interest for improving the efficiency of drug development, becoming the most frequent adaptive design type. It typically consists of two stages, the trial objectives being often different in each stage. The primary objectives are to select optimal experimental treatment group(s) in the first stage and compare the efficacy between the selected treatment and control groups in the second stage. In this article, we focus on a two-stage adaptive seamless design, for which treatment selection is based on the short-term binary endpoint and treatment comparison is based on the long-term binary endpoint. We thus propose an exact conditional test as a final analysis, based on the bivariate binomial distribution and given the selected treatment with the most promising short-term endpoint response rate from an interim analysis. Additionally, the mid- p $$ p $$ approach is incorporated to improve conservativeness for an exact test. Simulation studies were conducted to compare the proposed methods with a method based on the combination test. The proposed exact method controlled for type I error rate at the nominal level, regardless of the number of initial treatments or the correlation between short- and long-term endpoints. In terms of the treatment comparison power, the proposed methods are more powerful than that based on the combination test in the scenarios, with only one treatment being effective.


Assuntos
Projetos de Pesquisa , Simulação por Computador , Humanos , Seleção de Pacientes
15.
BMC Neurol ; 22(1): 219, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35698048

RESUMO

AIM: To investigate the cognitive function and its relation to the home discharge of patients following subacute stroke. METHODS: This retrospective cohort study included 1,229 convalescent patients experiencing their first subacute stroke. We determined discharge destination and demographic and clinical information. We recorded the following measurement scores: Mini-Mental State Examination (MMSE) score, Stroke Impairment Assessment Set score, grip strength, and Functional Independence Measure (FIM). We performed a multivariable logistic regression analysis with the forced-entry method to identify factors related to home discharge. RESULTS: Of the 1,229 participants (mean age: 68.7 ± 13.5 years), 501 (40.8%), 735 (59.8%), and 1,011 (82.3%) were female, had cerebral infarction, and were home discharged, respectively. Multivariable logistic regression analysis revealed that age (odds ratio [OR], 0.93; 95% confidence interval [CI], 0.91 - 0.96; P < 0.001), duration from stroke onset to admission (OR, 0.98; 95% CI, 0.96 - 0.99; P = 0.003), living situation (OR, 4.40; 95% CI, 2.69 - 7.20; P < 0.001), MMSE score at admission (OR, 1.05; 95% CI, 1.00 - 1.09; P = 0.035), FIM motor score at admission (OR, 1.04; 95% CI, 1.01 - 1.06; P = 0.001), and FIM cognitive score at admission (OR, 1.08; 95% CI, 1.04 - 1.13; P < 0.001) were significantly associated with home discharge. CONCLUSIONS: MMSE at admission is significantly associated with home discharge in patients with subacute stroke.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Atividades Cotidianas , Idoso , Idoso de 80 Anos ou mais , Cognição , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Alta do Paciente , Recuperação de Função Fisiológica , Estudos Retrospectivos
16.
Opt Express ; 29(15): 22847-22854, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34614563

RESUMO

To elucidate the microscopic origin of the thermal droop, a blue-emitting indium gallium nitride (InGaN) quantum well grown on epitaxially laterally overgrown gallium nitride was investigated using temperature-dependent microphotoluminescence spectroscopy. Below 300 K, the sample exhibited a well-known dislocation-tolerant luminescence behavior. However, as temperature increases from 300 K to 500 K, the near band-edge emission at the wing region (with lower threading dislocation densities) was stronger than that at the seed region (with higher threading dislocation densities), indicating that threading dislocations are the microscopic origin of the thermal droop. Considering the carrier diffusion length, edge-type threading dislocations should play a major role in the thermal droop of heteroepitaxially grown InGaN-based LEDs.

17.
Eur Radiol ; 31(2): 875-883, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32829418

RESUMO

OBJECTIVES: To investigate the clinical utility of the Vesical Imaging-Reporting and Data System (VI-RADS) by comparing its diagnostic performance for muscle-invasive bladder cancer (MIBC) between radiologists and urologists based on multiparametric MRI, including three-dimensional (3D) fast spin-echo (FSE) T2-weighted acquisitions. METHODS: This study included 66 treatment-naïve patients (60 men, 6 women; mean age 74.0 years) with pathologically proven bladder cancer who underwent multiparametric MRI, including 3D FSE T2-weighted imaging, before transurethral bladder tumour resection between January 2010 and November 2018. The MRI scans were categorised according to the five-point VI-RADS score by four independent readers (two board-certified radiologists and board-certified urologists each), blinded to the histopathological findings. The VI-RADS scores were compared with the postoperative histopathological diagnosis. Interobserver agreement was assessed using weighted kappa coefficients. ROC analysis and generalised estimating equations were used to evaluate the diagnostic performance. RESULTS: Forty-nine (74.2%) and 17 (25.8%) tumours were confirmed to be non-MIBC and MIBC, respectively, based on pathological examination. The interobserver agreement was good-to-excellent between all pairs of readers (range, 0.73-0.91). The urologists' sensitivity/specificity values for DCE-MRI VI-RADS scores were significantly lower than those of radiologists. No significant differences were observed for the overall VI-RADS score. The AUC for the overall VI-RADS score was 0.94, 0.92, 0.89, and 0.87 for radiologists 1 and 2 and urologists 1 and 2, respectively. CONCLUSIONS: The VI-RADS score, based on multiparametric MRI including 3D FSE T2-weighted acquisitions, can be useful for radiologists and urologists to determine the bladder cancer muscle invasion status preoperatively. KEY POINTS: • VI-RADS (using multiparametric MRI including 3D FSE T2-weighted acquisitions) achieves good to excellent interobserver agreement and has similar diagnostic performance for detecting muscle invasion by both radiologists and urologists. • The diagnostic performance of the overall VI-RADS score is high for both radiologists and urologists, particularly due to the dominant effect of diffusion-weighted imaging on the overall VI-RADS score. • The sensitivity and specificity values of the T2WI VI-RADS scores for four readers in our study (using 3D FSE T2-weighted acquisitions) were similar (with slightly higher specificity values) to previously published results (using 2D FSE T2-weighted acquisitions).


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Bexiga Urinária , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Músculos , Radiologistas , Sensibilidade e Especificidade , Neoplasias da Bexiga Urinária/diagnóstico por imagem , Urologistas
18.
Transpl Infect Dis ; 23(2): e13468, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32945064

RESUMO

Adenovirus (AdV) infection is a common complication in bone marrow/hematopoietic stem cell transplant and solid organ transplant recipients. AdV infection usually presents as hemorrhagic cystitis, but sometimes it can progress to acute kidney injury showing AdV nephritis (AdVN). We present the case of a 52-year-old Japanese female who had received a living kidney transplantation (KT) from her husband. At 21 months post-KT, the patient presented with a fever, but no renal dysfunction and no abnormal urine findings. A contrast-enhanced computed tomography (CT) scan revealed a few mass lesions with hypoperfusion in the transplanted kidney. An enhanced CT-guided biopsy targeting one of these lesions revealed a necrotizing tubulointerstitial nephritis suggesting AdVN. The polymerase chain reaction tests for ADV were negative in a urine sample but positive in the sera and the frozen kidney biopsy samples. AdVN can manifest as an unusual pattern of acute lobar nephritis/acute focal bacterial nephritis-like localization without symptoms of acute kidney injury or urinary tract infection. Enhanced CT can provide clues for clinical diagnosis.


Assuntos
Infecções por Adenoviridae/complicações , Nefrite , Injúria Renal Aguda , Adenoviridae , Aloenxertos , Feminino , Humanos , Rim , Pessoa de Meia-Idade , Nefrite/virologia , Infecções Urinárias
19.
Clin Nephrol ; 95(4): 208-214, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33560220

RESUMO

Polyuria in post-kidney transplant (KT) patients is a common condition generally attributed to delayed tubular function, fluid administration, and solute diuresis. Since excessive water intake post-KT physiologically suppresses arginine vasopressin (AVP) secretion, central diabetes insipidus (CDI) caused by deficient primary AVP release can be overlooked. Although DDAVP (desmopressin) - a selective AVP V2 receptor agonist - has been used to treat massive polyuria, CDI rarely progresses to kidney injury due to the preservation of fluid balance by thirst-dependent osmoregulation. Administration of DDAVP in post-KT recipients with mild polyuria and subclinical CDI is difficult to assess, and whether long-term use of DDAVP is beneficial for the transplanted kidney has not been established. We present the case of a 36-year-old Japanese female who was diagnosed with subclinical/partial CDI post KT. CDI was caused by a sequela of suprasellar germinoma. Graft function gradually declined without evidence of hypovolemia or hypernatremia, and a kidney biopsy revealed advanced ischemic kidney injury. Although daily oral DDAVP administration did not increase extracellular fluid volume, treatment resulted in a gradual improvement of graft function, and a follow-up transplanted kidney biopsy indicated substantial recovery.


Assuntos
Desamino Arginina Vasopressina/uso terapêutico , Diabetes Insípido Neurogênico/tratamento farmacológico , Isquemia/etiologia , Transplante de Rim/efeitos adversos , Rim/irrigação sanguínea , Administração Oral , Adulto , Feminino , Humanos
20.
Stat Med ; 39(9): 1264-1274, 2020 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-31916260

RESUMO

The mixed effect models for repeated measures (MMRM) analysis is sometimes used as a primary analysis in longitudinal randomized clinical trials. The SE for the treatment effect in the MMRM analysis is usually estimated by assuming the orthogonality of the fixed effect and variance-covariance parameters, which is the orthogonality property of a multivariate normal distribution, because of default settings of most standard statistical software. However, this property might be lost when analysis models are misspecified and/or data include missing values with the mechanism of being missing at random. In this study, we investigated the effect of the assumption of the orthogonality property on the estimation of the SE for the MMRM analysis. From simulation and case studies, it was shown that the SE with the assumption of orthogonality property had nonnegligible bias, especially when the analysis models assuming heteroscedasticity between treatment groups were applied. We also introduce the SAS code for the MMRM analysis without assuming the orthogonality property. Assuming the orthogonality property in the MMRM analysis would lead to invalid statistical inference, and it is necessary to be careful when applying the MMRM analysis with most standard software.


Assuntos
Modelos Estatísticos , Projetos de Pesquisa , Viés , Simulação por Computador , Humanos , Estudos Longitudinais
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