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1.
J Cell Sci ; 136(19)2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37701987

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) exhibits elevated levels of autophagy, which promote tumor progression and treatment resistance. ATG4B is an autophagy-related cysteine protease under consideration as a potential therapeutic target, but it is largely unexplored in PDAC. Here, we investigated the clinical and functional relevance of ATG4B expression in PDAC. Using two PDAC patient cohorts, we found that low ATG4B mRNA or protein expression is associated with worse patient survival outcomes, poorly differentiated PDAC tumors and a lack of survival benefit from adjuvant chemotherapy. In PDAC cell lines, ATG4B knockout reduced proliferation, abolished processing of LC3B (also known as MAP1LC3B), and reduced GABARAP and GABARAPL1 levels, but increased ATG4A levels. ATG4B and ATG4A double knockout lines displayed a further reduction in proliferation, characterized by delays in G1-S phase transition and mitosis. Pro-LC3B accumulated aberrantly at the centrosome with a concomitant increase in centrosomal proteins PCM1 and CEP131, which was rescued by exogenous ATG4B. The two-stage cell cycle defects following ATG4B and ATG4A loss have important therapeutic implications for PDAC.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Proteínas Relacionadas à Autofagia/genética , Proteínas Relacionadas à Autofagia/metabolismo , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Neoplasias Pancreáticas/genética , Autofagia/genética , Linhagem Celular Tumoral , Ciclo Celular/genética , Proliferação de Células/genética , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Neoplasias Pancreáticas
2.
Gastroenterology ; 166(1): 88-102, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37704112

RESUMO

BACKGROUND & AIMS: There is a need to develop safe and effective pharmacologic options for the treatment of celiac disease (CeD); however, consensus on the appropriate design and configuration of randomized controlled trials (RCTs) in this population is lacking. METHODS: A 2-round modified Research and Development/University of California Los Angeles Appropriateness Method study was conducted. Eighteen gastroenterologists (adult and pediatric) and gastrointestinal pathologists voted on statements pertaining to the configuration of CeD RCTs, inclusion and exclusion criteria, gluten challenge, and trial outcomes. Two RCT designs were considered, representing the following distinct clinical scenarios for which pharmacotherapy may be used: trials incorporating a gluten challenge to simulate exposure; and trials evaluating reversal of histologic changes, despite attempted adherence to a gluten-free diet. Each statement was rated as appropriate, uncertain, or inappropriate, using a 9-point Likert scale. RESULTS: For trials evaluating prevention of relapse after gluten challenge, participants adherent to a gluten-free diet for 12 months or more with normal or near-normal-sized villi should be enrolled. Gluten challenge should be FODMAPS (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) free, and efficacy evaluated using histology with a secondary patient-reported outcome measure. For trials evaluating reversal of villus atrophy, the panel voted it appropriate to enroll participants with a baseline villus height to crypt depth ratio ≤2 and measure efficacy using a primary histologic end point. Guidance for measuring histologic, endoscopic, and patient-reported outcomes in adult and pediatric patients with CeD are provided, along with recommendations regarding the merits and limitations of different end points. CONCLUSIONS: We developed standardized recommendations for clinical trial design, eligibility criteria, outcome measures, gluten challenge, and disease evaluations for RCTs in patients with CeD.


Assuntos
Doença Celíaca , Adulto , Humanos , Criança , Doença Celíaca/patologia , Recidiva Local de Neoplasia , Ensaios Clínicos Controlados Aleatórios como Assunto , Glutens/efeitos adversos , Dieta Livre de Glúten
3.
Am J Pathol ; 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39222907

RESUMO

Delayed diagnosis and treatment resistance make pancreatic ductal adenocarcinoma (PDAC) mortality rates high. Identifying molecular subtypes can improve treatment, but current methods are costly and time-consuming. In this study, deep learning models were utilized to identify histological features that classify PDAC molecular subtypes based on routine hematoxylin-eosin (H&E)-stained histopathological slides. 97 histopathology slides associated with resectable PDAC from the Cancer Genome Atlas (TCGA) project were utilized to train a deep learning model and tested the performance on 44 needle biopsy material (110 slides) from a local annotated patient cohort. The model achieved balanced accuracy of 96.19% and 83.03% in identifying the classical and basal subtypes of PDAC in the TCGA and the local cohort, respectively. This study provides a promising method to cost-effectively and rapidly classifying PDAC molecular subtypes based on routine H&E slides, potentially leading to more effective clinical management of this disease.

4.
Cereb Cortex ; 34(1)2024 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-37950874

RESUMO

Cortical neurons of eutherian mammals project to the contralateral hemisphere, crossing the midline primarily via the corpus callosum and the anterior, posterior, and hippocampal commissures. We recently reported and named the thalamic commissures (TCs) as an additional interhemispheric axonal fiber pathway connecting the cortex to the contralateral thalamus in the rodent brain. Here, we demonstrate that TCs also exist in primates and characterize the connectivity of these pathways with high-resolution diffusion-weighted MRI, viral axonal tracing, and fMRI. We present evidence of TCs in both New World (Callithrix jacchus and Cebus apella) and Old World primates (Macaca mulatta). Further, like rodents, we show that the TCs in primates develop during the embryonic period, forming anatomical and functionally active connections of the cortex with the contralateral thalamus. We also searched for TCs in the human brain, showing their presence in humans with brain malformations, although we could not identify TCs in healthy subjects. These results pose the TCs as a vital fiber pathway in the primate brain, allowing for more robust interhemispheric connectivity and synchrony and serving as an alternative commissural route in developmental brain malformations.


Assuntos
Substância Branca , Animais , Humanos , Substância Branca/diagnóstico por imagem , Encéfalo , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/fisiologia , Tálamo/diagnóstico por imagem , Macaca mulatta , Mamíferos
5.
Proc Natl Acad Sci U S A ; 118(37)2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34493677

RESUMO

The common marmoset has enormous promise as a nonhuman primate model of human brain functions. While resting-state functional MRI (fMRI) has provided evidence for a similar organization of marmoset and human cortices, the technique cannot be used to map the functional correspondences of brain regions between species. This limitation can be overcome by movie-driven fMRI (md-fMRI), which has become a popular tool for noninvasively mapping the neural patterns generated by rich and naturalistic stimulation. Here, we used md-fMRI in marmosets and humans to identify whole-brain functional correspondences between the two primate species. In particular, we describe functional correlates for the well-known human face, body, and scene patches in marmosets. We find that these networks have a similar organization in both species, suggesting a largely conserved organization of higher-order visual areas between New World marmoset monkeys and humans. However, while face patches in humans and marmosets were activated by marmoset faces, only human face patches responded to the faces of other animals. Together, the results demonstrate that higher-order visual processing might be a conserved feature between humans and New World marmoset monkeys but that small, potentially important functional differences exist.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Callithrix/fisiologia , Face/fisiologia , Imageamento por Ressonância Magnética/métodos , Vias Neurais , Percepção Visual/fisiologia , Adulto , Animais , Encéfalo/anatomia & histologia , Face/anatomia & histologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
Alzheimers Dement ; 20(5): 3455-3471, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38574388

RESUMO

INTRODUCTION: Fundamental questions remain about the key mechanisms that initiate Alzheimer's disease (AD) and the factors that promote its progression. Here we report the successful generation of the first genetically engineered marmosets that carry knock-in (KI) point mutations in the presenilin 1 (PSEN1) gene that can be studied from birth throughout lifespan. METHODS: CRISPR/Cas9 was used to generate marmosets with C410Y or A426P point mutations in PSEN1. Founders and their germline offspring are comprehensively studied longitudinally using non-invasive measures including behavior, biomarkers, neuroimaging, and multiomics signatures. RESULTS: Prior to adulthood, increases in plasma amyloid beta were observed in PSEN1 mutation carriers relative to non-carriers. Analysis of brain revealed alterations in several enzyme-substrate interactions within the gamma secretase complex prior to adulthood. DISCUSSION: Marmosets carrying KI point mutations in PSEN1 provide the opportunity to study the earliest primate-specific mechanisms that contribute to the molecular and cellular root causes of AD onset and progression. HIGHLIGHTS: We report the successful generation of genetically engineered marmosets harboring knock-in point mutations in the PSEN1 gene. PSEN1 marmosets and their germline offspring recapitulate the early emergence of AD-related biomarkers. Studies as early in life as possible in PSEN1 marmosets will enable the identification of primate-specific mechanisms that drive disease progression.


Assuntos
Doença de Alzheimer , Callithrix , Presenilina-1 , Animais , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Animais Geneticamente Modificados , Encéfalo/patologia , Encéfalo/metabolismo , Sistemas CRISPR-Cas , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Mutação/genética , Mutação Puntual/genética , Presenilina-1/genética
7.
Vet Surg ; 53(2): 254-263, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37822110

RESUMO

OBJECTIVE: To compare vertebral implant placement in the canine thoracolumbar spine between 3D-printed patient-specific drill guides (3DPG) and the conventional freehand technique (FH). STUDY DESIGN: Ex vivo study. ANIMALS: Cadaveric canine spines (n = 24). METHODS: Implant trajectories were established for the left and right sides of the T10 through L6 vertebrae based on computed tomography (CT) imaging. Customized drill guides were created for each vertebra of interest. Each cadaver was randomly assigned to one of six veterinarians with varying levels of experience placing vertebral implants. Vertebrae were randomly assigned a surgical order and technique (3DPG or FH) for both sides. Postoperative CT images were acquired. A single, blinded observer assessed pin placement using a modified Zdichavsky classification. RESULTS: A total of 480 implants were placed in 240 vertebrae. Three sites were excluded from the analysis; therefore, a total of 238 implants were evaluated using the FH technique and 239 implants using 3DPG. When evaluating implant placement, 152/239 (63.6%) of 3DPG implants were considered to have an acceptable placement in comparison with 115/248 (48.32%) with FH. Overall, pin placement using 3DPG was more likely to provide acceptable pin placement (p < .001) in comparison with the FH technique for surgeons at all levels of experience. CONCLUSION: The use of 3DPG was shown to be better than the conventional freehand technique regarding acceptable placement of implants in the thoracolumbar spine of canine cadavers. CLINICAL SIGNIFICANCE: Utilizing 3DPG can be considered better than the traditional FH technique when placing implants in the canine thoracolumbar spine.


Assuntos
Doenças do Cão , Fusão Vertebral , Cirurgia Assistida por Computador , Animais , Cães , Cadáver , Doenças do Cão/cirurgia , Fusão Vertebral/instrumentação , Fusão Vertebral/métodos , Fusão Vertebral/veterinária , Cirurgia Assistida por Computador/instrumentação , Cirurgia Assistida por Computador/métodos , Cirurgia Assistida por Computador/veterinária , Tomografia Computadorizada por Raios X/veterinária , Tomografia Computadorizada por Raios X/métodos , Distribuição Aleatória , Pinos Ortopédicos
8.
Artigo em Inglês | MEDLINE | ID: mdl-38056798

RESUMO

BACKGROUND & AIMS: The operating properties of histologic indices for evaluating Crohn's disease (CD) activity are poorly characterized. We assessed the reliability and responsiveness of existing histologic indices/items used in CD and ulcerative colitis (UC), in addition to 3 novel items, and developed exploratory ileal, colonic, and colonic-ileal CD instruments. METHODS: Blinded central readers independently reviewed paired baseline and week 12 image sets from the EXTEND trial. Disease activity was scored using 4 indices (the Global Histologic Activity Score, Geboes Score, Nancy Histological Index, and Robarts Histopathology Index) and 3 items identified by an expert panel (mucin depletion, basal plasmacytosis, and ileal pyloric gland metaplasia). Reliability and responsiveness were quantified using the intraclass correlation coefficient (ICC) and area under the receiver operating curve (AUC), respectively. Exploratory indices were developed using backward stepwise linear regression analysis. Candidate independent variables were items with an inter-rater ICC ≥0.40 and AUC ≥0.56. The dependent variable was histologic disease activity measured by a 100-mm visual analogue scale. RESULTS: Paired image sets were available from 55 patients. Substantial to almost perfect inter-rater reliability (ICC, 0.63-0.87) and some responsiveness (AUC, 0.57-0.94) were observed for all existing indices regardless of whether individual colonic and ileal segments, combined colonic segments, or combined colonic and ileal segments were assessed and the calculation method used. Five items were tested as candidate items, and exploratory colonic, ileal, and colonic-ileal indices were developed. CONCLUSIONS: CD and UC indices were similarly reliable and responsive in measuring histologic CD activity. Exploratory index development did not offer benefit over current histologic instruments.

9.
Gastroenterology ; 163(6): 1531-1546.e8, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35985511

RESUMO

BACKGROUND & AIMS: To examine whether quantitative pathologic analysis of digitized hematoxylin and eosin slides of colorectal carcinoma (CRC) correlates with clinicopathologic features, molecular alterations, and prognosis. METHODS: A quantitative segmentation algorithm (QuantCRC) was applied to 6468 digitized hematoxylin and eosin slides of CRCs. Fifteen parameters were recorded from each image and tested for associations with clinicopathologic features and molecular alterations. A prognostic model was developed to predict recurrence-free survival using data from the internal cohort (n = 1928) and validated on an internal test (n = 483) and external cohort (n = 938). RESULTS: There were significant differences in QuantCRC according to stage, histologic subtype, grade, venous/lymphatic/perineural invasion, tumor budding, CD8 immunohistochemistry, mismatch repair status, KRAS mutation, BRAF mutation, and CpG methylation. A prognostic model incorporating stage, mismatch repair, and QuantCRC resulted in a Harrell's concordance (c)-index of 0.714 (95% confidence interval [CI], 0.702-0.724) in the internal test and 0.744 (95% CI, 0.741-0.754) in the external cohort. Removing QuantCRC from the model reduced the c-index to 0.679 (95% CI, 0.673-0.694) in the external cohort. Prognostic risk groups were identified, which provided a hazard ratio of 2.24 (95% CI, 1.33-3.87, P = .004) for low vs high-risk stage III CRCs and 2.36 (95% CI, 1.07-5.20, P = .03) for low vs high-risk stage II CRCs, in the external cohort after adjusting for established risk factors. The predicted median 36-month recurrence rate for high-risk stage III CRCs was 32.7% vs 13.4% for low-risk stage III and 15.8% for high-risk stage II vs 5.4% for low-risk stage II CRCs. CONCLUSIONS: QuantCRC provides a powerful adjunct to routine pathologic reporting of CRC. A prognostic model using QuantCRC improves prediction of recurrence-free survival.


Assuntos
Neoplasias Colorretais , Neoplasias Testiculares , Humanos , Masculino , Neoplasias Colorretais/genética , Reparo de Erro de Pareamento de DNA , Amarelo de Eosina-(YS) , Hematoxilina
10.
Cereb Cortex ; 32(9): 1965-1977, 2022 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-34515315

RESUMO

Frontoparietal networks contribute to complex cognitive functions in humans and macaques, such as working memory, attention, task-switching, response suppression, grasping, reaching, and eye movement control. However, there has been no comprehensive examination of the functional organization of frontoparietal networks using functional magnetic resonance imaging in the New World common marmoset monkey (Callithrix jacchus), which is now widely recognized as a powerful nonhuman primate experimental animal. In this study, we employed hierarchical clustering of interareal blood oxygen level-dependent signals to investigate the hypothesis that the organization of the frontoparietal cortex in the marmoset follows the organizational principles of the macaque frontoparietal system. We found that the posterior part of the lateral frontal cortex (premotor regions) was functionally connected to the anterior parietal areas, while more anterior frontal regions (frontal eye field [FEF]) were connected to more posterior parietal areas (the region around the lateral intraparietal area [LIP]). These overarching patterns of interareal organization are consistent with a recent macaque study. These findings demonstrate parallel frontoparietal processing streams in marmosets and support the functional similarities of FEF-LIP and premotor-anterior parietal pathways between marmoset and macaque.


Assuntos
Callithrix , Imageamento por Ressonância Magnética , Animais , Mapeamento Encefálico , Callithrix/fisiologia , Córtex Cerebral , Lobo Frontal/diagnóstico por imagem , Lobo Frontal/fisiologia , Macaca , Vigília
11.
Proc Natl Acad Sci U S A ; 117(35): 21681-21689, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32817555

RESUMO

With the medial frontal cortex (MFC) centrally implicated in several major neuropsychiatric disorders, it is critical to understand the extent to which MFC organization is comparable between humans and animals commonly used in preclinical research (namely rodents and nonhuman primates). Although the cytoarchitectonic structure of the rodent MFC has mostly been conserved in humans, it is a long-standing question whether the structural analogies translate to functional analogies. Here, we probed this question using ultra high field fMRI data to compare rat, marmoset, and human MFC functional connectivity. First, we applied hierarchical clustering to intrinsically define the functional boundaries of the MFC in all three species, independent of cytoarchitectonic definitions. Then, we mapped the functional connectivity "fingerprints" of these regions with a number of different brain areas. Because rats do not share cytoarchitectonically defined regions of the lateral frontal cortex (LFC) with primates, the fingerprinting method also afforded the unique ability to compare the rat MFC and marmoset LFC, which have often been suggested to be functional analogs. The results demonstrated remarkably similar intrinsic functional organization of the MFC across the species, but clear differences between rodent and primate MFC whole-brain connectivity. Rat MFC patterns of connectivity showed greatest similarity with premotor regions in the marmoset, rather than dorsolateral prefrontal regions, which are often suggested to be functionally comparable. These results corroborate the viability of the marmoset as a preclinical model of human MFC dysfunction, and suggest divergence of functional connectivity between rats and primates in both the MFC and LFC.


Assuntos
Vias Neurais/fisiologia , Córtex Pré-Frontal/fisiologia , Animais , Evolução Biológica , Encéfalo/fisiologia , Mapeamento Encefálico/métodos , Callithrix/anatomia & histologia , Conectoma/métodos , Feminino , Lobo Frontal/anatomia & histologia , Lobo Frontal/fisiologia , Substância Cinzenta/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/anatomia & histologia , Córtex Pré-Frontal/anatomia & histologia , Ratos , Ratos Wistar
12.
Neuroimage ; 252: 119030, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35217206

RESUMO

The common marmoset (Callithrix jacchus) is quickly gaining traction as a premier neuroscientific model. However, considerable progress is still needed in understanding the functional and structural organization of the marmoset brain to rival that documented in longstanding preclinical model species, like mice, rats, and Old World primates. To accelerate such progress, we present the Marmoset Functional Brain Connectivity Resource (marmosetbrainconnectome.org), currently consisting of over 70 h of resting-state fMRI (RS-fMRI) data acquired at 500 µm isotropic resolution from 31 fully awake marmosets in a common stereotactic space. Three-dimensional functional connectivity (FC) maps for every cortical and subcortical gray matter voxel are stored online. Users can instantaneously view, manipulate, and download any whole-brain functional connectivity (FC) topology (at the subject- or group-level) along with the raw datasets and preprocessing code. Importantly, researchers can use this resource to test hypotheses about FC directly - with no additional analyses required - yielding whole-brain correlations for any gray matter voxel on demand. We demonstrate the resource's utility for presurgical planning and comparison with tracer-based neuronal connectivity as proof of concept. Complementing existing structural connectivity resources for the marmoset brain, the Marmoset Functional Brain Connectivity Resource affords users the distinct advantage of exploring the connectivity of any voxel in the marmoset brain, not limited to injection sites nor constrained by regional atlases. With the entire raw database (RS-fMRI and structural images) and preprocessing code openly available for download and use, we expect this resource to be broadly valuable to test novel hypotheses about the functional organization of the marmoset brain.


Assuntos
Callithrix , Vigília , Acesso à Informação , Animais , Encéfalo/fisiologia , Callithrix/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Camundongos , Ratos
13.
Gastroenterology ; 160(6): 2119-2132.e9, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33524400

RESUMO

BACKGROUND AND AIMS: Homologous recombination deficiency (HRD) in pancreatic ductal adenocarcinoma (PDAC), remains poorly defined beyond germline (g) alterations in BRCA1, BRCA2, and PALB2. METHODS: We interrogated whole genome sequencing (WGS) data on 391 patients, including 49 carriers of pathogenic variants (PVs) in gBRCA and PALB2. HRD classifiers were applied to the dataset and included (1) the genomic instability score (GIS) used by Myriad's MyChoice HRD assay; (2) substitution base signature 3 (SBS3); (3) HRDetect; and (4) structural variant (SV) burden. Clinical outcomes and responses to chemotherapy were correlated with HRD status. RESULTS: Biallelic tumor inactivation of gBRCA or PALB2 was evident in 43 of 49 germline carriers identifying HRD-PDAC. HRDetect (score ≥0.7) predicted gBRCA1/PALB2 deficiency with highest sensitivity (98%) and specificity (100%). HRD genomic tumor classifiers suggested that 7% to 10% of PDACs that do not harbor gBRCA/PALB2 have features of HRD. Of the somatic HRDetecthi cases, 69% were attributed to alterations in BRCA1/2, PALB2, RAD51C/D, and XRCC2, and a tandem duplicator phenotype. TP53 loss was more common in BRCA1- compared with BRCA2-associated HRD-PDAC. HRD status was not prognostic in resected PDAC; however in advanced disease the GIS (P = .02), SBS3 (P = .03), and HRDetect score (P = .005) were predictive of platinum response and superior survival. PVs in gATM (n = 6) or gCHEK2 (n = 2) did not result in HRD-PDAC by any of the classifiers. In 4 patients, BRCA2 reversion mutations associated with platinum resistance. CONCLUSIONS: Germline and parallel somatic profiling of PDAC outperforms germline testing alone in identifying HRD-PDAC. An additional 7% to 10% of patients without gBRCA/PALB2 mutations may benefit from DNA damage response agents.


Assuntos
Carcinoma Ductal Pancreático/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Genes BRCA1 , Genes BRCA2 , Neoplasias Pancreáticas/genética , Reparo de DNA por Recombinação , Idoso , Alelos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/terapia , Cisplatino/administração & dosagem , Proteínas de Ligação a DNA/genética , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Fluoruracila/uso terapêutico , Instabilidade Genômica , Mutação em Linhagem Germinativa , Recombinação Homóloga , Humanos , Irinotecano/uso terapêutico , Leucovorina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Oxaliplatina/uso terapêutico , Pancreatectomia , Neoplasias Pancreáticas/terapia , Prognóstico , Sensibilidade e Especificidade , Taxa de Sobrevida , Proteína Supressora de Tumor p53/genética , Sequenciamento Completo do Genoma , Gencitabina
14.
Gastroenterology ; 160(7): 2291-2302, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33610533

RESUMO

BACKGROUND & AIMS: Histopathology is an emerging treatment target in ulcerative colitis (UC) clinical trials. Our aim was to provide guidance on standardizing biopsy collection protocols, identifying optimal evaluative indices, and defining thresholds for histologic response and remission after treatment. METHODS: An international, interdisciplinary expert panel of 19 gastroenterologists and gastrointestinal pathologists was assembled. A modified RAND/University of California, Los Angeles appropriateness methodology was used to address relevant issues. A total of 138 statements were derived from a systematic review of the literature and expert opinion. Each statement was anonymously rated as appropriate, uncertain, or inappropriate using a 9-point scale. Survey results were reviewed and discussed before a second round of voting. RESULTS: Histologic measurements collected using a uniform biopsy strategy are important for assessing disease activity and determining therapeutic efficacy in UC clinical trials. Multiple biopsy strategies were deemed acceptable, including segmental biopsies collected according to the endoscopic appearance. Biopsies should be scored for architectural change, lamina propria chronic inflammation, basal plasmacytosis, lamina propria and epithelial neutrophils, epithelial damage, and erosions/ulcerations. The Geboes score, Robarts Histopathology Index, and Nancy Index were considered appropriate for assessing histologic activity; use of the modified Riley score and Harpaz Index were uncertain. Histologic activity at baseline should be required for enrollment, recognizing this carries operational implications. Achievement of histologic improvement or remission was considered an appropriate and realistic therapeutic target. Current histologic indices require validation for pediatric populations. CONCLUSIONS: These recommendations provide a framework for standardized implementation of histopathology in UC trials. Additional work is required to address operational considerations and areas of uncertainty.


Assuntos
Biópsia/normas , Ensaios Clínicos como Assunto/normas , Colite Ulcerativa , Gastroenterologia/normas , Patologia Clínica/normas , Consenso , Humanos , Padrões de Referência , Indução de Remissão
15.
Am J Gastroenterol ; 117(2): 264-271, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34797816

RESUMO

INTRODUCTION: The optimal instrument for assessing histologic disease activity in patients with eosinophilic esophagitis (EoE) is unclear. We assessed the responsiveness of the EoE Histologic Scoring System (EoE-HSS) when compared with that of the peak eosinophil count (PEC). METHODS: Histopathology slides were obtained from patients with EoE at baseline and after 8 weeks of treatment with swallowed topical budesonide or elimination diet. Two blinded gastrointestinal pathologists scored biopsies on the EoE-HSS, PEC, and 100-mm visual analog scale (VAS) of overall histologic severity. Change was defined as an improvement by ≥0.5 SD in baseline VAS. Responsiveness was quantified using the standardized effect size (SES) and the probability that the index distinguishes a patient with improvement from a patient without improvement, which is the area under the receiver operating characteristic curve (AUC). Longitudinal validity was assessed using Pearson correlations between changes in EoE-HSS and both PEC and VAS. RESULTS: The EoE-HSS grade (SES 2.18 [95% confidence interval, CI: 1.46-2.88]; AUC 0.73 [95% CI: 0.57-0.84]) and stage (SES 2.07 [95% CI: 1.37-2.77]; AUC 0.73 [95% CI: 0.58-0.84]) were highly responsive, similar to PEC (SES 1.44 [95% CI: 0.80-2.07]; AUC 0.73 [95% CI: 0.58-0.84]). The EoE-HSS grade and stage were more highly correlated with changes in VAS (grade 0.92 [95% CI: 0.86-0.95]; stage 0.89 [95% CI: 0.81-0.94]) than with changes in PEC (grade 0.74 [95% CI: 0.58-0.85]; stage 0.66 [95% CI: 0.47-0.80]). DISCUSSION: The EoE-HSS is highly responsive, performs similarly to PEC, and is better correlated with changes in overall histologic activity in patients with EoE.


Assuntos
Esofagite Eosinofílica/patologia , Eosinófilos/patologia , Esofagoscopia/métodos , Adulto , Biópsia , Feminino , Seguimentos , Humanos , Contagem de Leucócitos , Masculino , Estudos Prospectivos , Índice de Gravidade de Doença
16.
J Clin Gastroenterol ; 56(3): 243-248, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33780220

RESUMO

BACKGROUND: Serrated lesions give rise to 15% to 30% of all colorectal cancers, driven predominantly by the sessile serrated polyp (SSP). Fecal immunochemical test (FIT), has low sensitivity for SSPs. SSP detection rate (SSPDR) is influenced by performance of both endoscopists and pathologists, as diagnosis can be subtle both on endoscopy and histology. GOALS: To evaluate the SSPDR in a population-based screening program, and the influence of subspecialty trained pathologists on provincial reporting practices. STUDY: The colon screening program database was used to identify all FIT-positive patients that received colonoscopy between January 2014 and June 2017. Patient demographics, colonoscopy quality indicators, pathologic diagnoses, and FIT values were collected. This study received IRB approval. RESULTS: A total of 74,605 colonoscopies were included and 26.6% had at least 1 serrated polyp removed. The SSPDR was 7.0%, with 59% of the SSPs detected having a concurrent conventional adenoma. The mean FIT value for colonoscopies with only serrated lesions was less than that for colonoscopies with a conventional adenoma or colorectal cancer (P<0.0001). Centers with a gastrointestinal subspecialty pathologist diagnosed proportionally more SSPs (P<0.0001), and right-sided SSPs than centers without subspecialists. CONCLUSIONS: Serrated lesions often occur in conjunction with conventional adenomas and are associated with lower FIT values. Knowledge of the characteristics of SSPs is essential for pathologists to ensure accurate diagnosis of SSPs.


Assuntos
Adenoma , Pólipos do Colo , Neoplasias Colorretais , Programas de Rastreamento , Adenoma/diagnóstico , Adenoma/patologia , Pólipos do Colo/diagnóstico , Pólipos do Colo/patologia , Colonoscopia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/patologia , Humanos
17.
J Pathol ; 254(3): 254-264, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33797756

RESUMO

Hereditary diffuse gastric cancer (HDGC) is a cancer syndrome caused by germline variants in CDH1, the gene encoding the cell-cell adhesion molecule E-cadherin. Loss of E-cadherin in cancer is associated with cellular dedifferentiation and poor prognosis, but the mechanisms through which CDH1 loss initiates HDGC are not known. Using single-cell RNA sequencing, we explored the transcriptional landscape of a murine organoid model of HDGC to characterize the impact of CDH1 loss in early tumourigenesis. Progenitor populations of stratified squamous and simple columnar epithelium, characteristic of the mouse stomach, showed lineage-specific transcriptional programs. Cdh1 inactivation resulted in shifts along the squamous differentiation trajectory associated with aberrant expression of genes central to gastrointestinal epithelial differentiation. Cytokeratin 7 (CK7), encoded by the differentiation-dependent gene Krt7, was a specific marker for early neoplastic lesions in CDH1 carriers. Our findings suggest that deregulation of developmental transcriptional programs may precede malignancy in HDGC. © 2021 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Caderinas/genética , Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica/genética , Predisposição Genética para Doença/genética , Neoplasias Gástricas/genética , Animais , Transformação Celular Neoplásica/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Organoides , Análise de Célula Única , Neoplasias Gástricas/patologia , Transcriptoma
18.
Vet Surg ; 51(7): 1106-1110, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35815735

RESUMO

OBJECTIVE: To assess the effect of repeated freezing and thawing on the suture pull-out strength in arytenoid and cricoid cartilages subjected to the laryngoplasty (LP) procedure. STUDY DESIGN: Ex vivo experimental study. SAMPLE POPULATION: Ten grossly normal equine cadaveric larynges. METHODS: Bilateral LP constructs were created using a standard LP technique. One hemilarynx was randomly allocated to the single freeze and thaw group and the other allocated to the repeated freeze and thaw (3 complete cycles) group. The suture ends of each LP construct were attached to a load frame and subjected to monotonic loading until construct failure. Mean load (N) and displacement (mm) at LP construct failure were compared between groups. RESULTS: All LP constructs failed by suture pull through the arytenoid cartilage. The mean load at failure was similar between groups (118.9 ± 25.5 N in the single freeze and thaw group and 113.4 ± 20.5 N in the repeated freeze and thaw group, P = .62). The mean displacement at failure was similar between groups (54.4 ± 15.1 mm in the single freeze and thaw group and 54.4 ± 15.4 mm in the repeated freeze and thaw group, P = .99). CONCLUSION: Repeated freezing and thawing did not affect the suture pullout strength of the arytenoid and cricoid cartilages. CLINICAL SIGNIFICANCE: Laryngeal specimens that have been subjected to repeated freezing and thawing can be utilized in the experimental evaluation of LP procedures because there is no alteration of the suture pull-out strength of the relevant cartilages.


Assuntos
Congelamento , Laringoplastia , Suturas , Animais , Cartilagem Aritenoide/cirurgia , Cadáver , Cartilagem Cricoide/cirurgia , Cavalos/cirurgia , Laringoplastia/métodos , Laringoplastia/veterinária , Suturas/veterinária
19.
Gut ; 70(10): 1894-1903, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-32933947

RESUMO

OBJECTIVE: To describe the clinical, pathological and genomic characteristics of pancreatic cancer with DNA mismatch repair deficiency (MMRD) and proficiency (MMRP). DESIGN: We identified patients with MMRD and MMRP pancreatic cancer in a clinical cohort (N=1213, 519 with genetic testing, 53 with immunohistochemistry (IHC)) and a genomic cohort (N=288 with whole-genome sequencing (WGS)). RESULTS: 12 out of 1213 (1.0%) in the clinical cohort were MMRD by IHC or WGS. Of the 14 patients with Lynch syndrome, 3 (21.4%) had an MMRP pancreatic cancer by IHC, and 4 (28.6%) were excluded because tissue was unavailable for testing. MMRD cancers had longer overall survival after surgery (weighted HR after coarsened exact matching 0.11, 95% CI 0.02 to 0.78, p=0.001). One patient with an unresectable MMRD cancer has an ongoing partial response 3 years after starting treatment with PD-L1/CTLA-4 inhibition. This tumour showed none of the classical histopathological features of MMRD. 9 out of 288 (3.1%) tumours with WGS were MMRD. Despite markedly higher tumour mutational burden and neoantigen loads, MMRD cancers were significantly less likely to have mutations in usual pancreatic cancer driver genes like KRAS and SMAD4, but more likely to have mutations in genes that drive cancers with microsatellite instability like ACV2RA and JAK1. MMRD tumours were significantly more likely to have a basal-like transcriptional programme and elevated transcriptional markers of immunogenicity. CONCLUSIONS: MMRD pancreatic cancers have distinct clinical, pathological and genomic profiles. Patients with MMRD pancreatic cancer should be considered for basket trials targeting enhanced immunogenicity or the unique genomic drivers in these malignancies.


Assuntos
Adenocarcinoma/genética , Distúrbios no Reparo do DNA/genética , Neoplasias Pancreáticas/genética , Adenocarcinoma/patologia , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Distúrbios no Reparo do DNA/patologia , Feminino , Testes Genéticos , Genômica , Humanos , Masculino , Instabilidade de Microssatélites , Mutação , Ontário , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos , Sequenciamento Completo do Genoma
20.
J Neurosci ; 40(48): 9236-9249, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33097633

RESUMO

Understanding the similarity of cortico-subcortical networks topologies between humans and nonhuman primate species is critical to study the origin of network alternations underlying human neurologic and neuropsychiatric diseases. The New World common marmoset (Callithrix jacchus) has become popular as a nonhuman primate model for human brain function. Most marmoset connectomic research, however, has exclusively focused on cortical areas, with connectivity to subcortical networks less extensively explored. Here, we aimed to first isolate patterns of subcortical connectivity with cortical resting-state networks in awake marmosets using resting-state fMRI, then to compare these networks with those in humans using connectivity fingerprinting. In this study, we used 5 marmosets (4 males, 1 female). While we could match several marmoset and human resting-state networks based on their functional fingerprints, we also found a few striking differences, for example, strong functional connectivity of the default mode network with the superior colliculus in marmosets that was much weaker in humans. Together, these findings demonstrate that many of the core cortico-subcortical networks in humans are also present in marmosets, but that small, potentially functionally relevant differences exist.SIGNIFICANCE STATEMENT The common marmoset is becoming increasingly popular as an additional preclinical nonhuman primate model for human brain function. Here we compared the functional organization of cortico-subcortical networks in marmosets and humans using ultra-high field fMRI. We isolated the patterns of subcortical connectivity with cortical resting-state networks (RSNs) in awake marmosets using resting-state fMRI and then compared these networks with those in humans using connectivity fingerprinting. While we could match several marmoset and human RSNs based on their functional fingerprints, we also found several striking differences. Together, these findings demonstrate that many of the core cortico-subcortical RSNs in humans are also present in marmosets, but that small, potentially functionally relevant differences exist.


Assuntos
Córtex Cerebral/fisiologia , Vias Neurais/fisiologia , Animais , Callithrix , Córtex Cerebral/diagnóstico por imagem , Conectoma , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Descanso/fisiologia , Especificidade da Espécie , Colículos Superiores/fisiologia
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