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1.
BMJ Open ; 13(2): e057151, 2023 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-36828648

RESUMO

OBJECTIVE: The non-metabolised antihistamine fexofenadine has oral absorption resulting from transporter activity. Uptake by enterocyte organic anion transporting polypeptides and efflux by an ATP-binding cassette transporter (P-glycoprotein) are primary determinants. Coeliac disease-mediated lesions to the small intestinal mucosa may alter oral absorption of the drug probe, fexofenadine. DESIGN: A phase I, open-label, single-dose, pharmacokinetic study SETTING: London, Ontario, Canada PARTICIPANTS: Patients with coeliac disease (n=41) with positive serology and healthy individuals (n=48). MAIN OUTCOME MEASURES: Patients with coeliac disease-duodenal histology and oral fexofenadine pharmacokinetics within a 3-week period. Healthy individuals-oral fexofenadine pharmacokinetics with water and grapefruit juice. RESULTS: Patients with coeliac disease were stratified by disease severity: Group A (n=15, normal), B+C (n=14, intraepithelial lymphocytosis with/without mild villous blunting) and D (n=12, moderate to severe villous blunting). Patients with coeliac disease in groups A, B+C and D and healthy individuals receiving water had similar fexofenadine AUC0-8 (2038±304, 2259±367, 2128±410, 1954±138 ng.h/mL; p>0.05; mean±SEM) and Cmax (440±73, 513±96, 523±104, 453±32 ng/mL; p>0.05), respectively. These four groups all had higher fexofenadine AUC0-8 (1063±59; p<0.01) and Cmax (253±18; p<0.05) compared with those for healthy individuals receiving grapefruit juice. Coeliac groups had a positive linear trend between disease severity and fexofenadine Tmax (2.0±0.3, 2.7±0.4, 3.1±0.5 hours; p<0.05). CONCLUSIONS: Coeliac disease severity based on duodenal histopathology did not affect oral fexofenadine bioavailability. Increased Tmax suggested absorption distal to the duodenum (jejunum + ileum), where histology seems more normal which may be the key determinant. Patients with coeliac disease may not require consideration for alternative clinical drug management for a number of non-metabolised and transport-mediated medications.


Assuntos
Doença Celíaca , Citrus paradisi , Humanos , Ontário , Terfenadina/farmacocinética , Água
2.
Transplant Proc ; 53(6): 1975-1979, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34272052

RESUMO

BACKGROUND: Recurrence of hepatocellular carcinoma (HCC) after liver transplantation is a major cause of morbidity and mortality. To date, there is no widely accepted pathologic assessment tool to predict HCC recurrence. In 2007, we developed a pathologic risk score that stratified patients into low, intermediate, or high risk for recurrence based on explant pathology. The aim of this study was to externally validate this risk score. METHODS: We retrospectively evaluated 124 patients over a 10-year period who underwent liver transplantation for HCC. Using explanted pathology reports, each patient was stratified according to the pathologic risk score and followed over time for HCC recurrence. RESULTS: Recurrence occurred in 15 patients (12%) after a mean follow-up of 25 months. Using the pathologic risk score, 10 (8%), 21 (17%), and 93 (75%) patients were stratified into high, intermediate, and low risk of recurrence, respectively. Among these risk groups, recurrence occurred in 50%, 28.5%, and 4.3% (P < .01) of patients, respectively. Using the optimal cutoff value ≤3.5, our risk score had a sensitivity of 80% and specificity of 79% with an area under the receiver operator characteristic curve of 0.8. Those with lower risk scores had higher recurrence-free survival (P < .0001). CONCLUSIONS: Our pathologic risk score accurately risks stratified patients for HCC recurrence after liver transplant. It can be used to tailor surveillance strategies for those deemed to be at elevated risk for recurrence.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transplante de Fígado , Carcinoma Hepatocelular/cirurgia , Humanos , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/efeitos adversos , Recidiva Local de Neoplasia , Estudos Retrospectivos , Fatores de Risco
3.
Folia Neuropathol ; 59(1): 98-103, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33969681

RESUMO

Several studies have recently described 4-repeat tauopathies that are characterized by the presence of globular glial inclusions. These inclusions are astrocytic or oligodendroglial, show extensive white matter involvement, and have a wide range of neuropathological and clinical presentations. Globular glial tauopathy (GGT) is classified into three subtypes according to clinical manifestations. Type I is characterized by frontotemporal lobar degeneration and represents a group of diseases with diverse clinical and histopathological features. Some of these disorders are associated with abnormal microtubule-associated protein tau gene. Type II presents as motor impairment due to pyramidal involvement, whereas type III is a combination of the features of types I and II. This report describes a rare case of GGT that manifested as depression and anxiety and demonstrates its neuropathological features. We have also compared the features of this case with those of previously reported cases and have revisited the classification.


Assuntos
Corpos de Inclusão/patologia , Neuroglia/patologia , Tauopatias/classificação , Tauopatias/patologia , Substância Branca/patologia , Proteínas tau/classificação , Idoso , Transtornos de Ansiedade/patologia , Autopsia , Depressão/patologia , Humanos , Masculino , Substância Branca/metabolismo
4.
BMJ Open ; 10(3): e034086, 2020 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-32139488

RESUMO

OBJECTIVE: Severity of coeliac disease depends in part on the extent of small intestinal mucosa injury. Patients with the most abnormal pathology have loss of duodenal villi CYP3A4, a drug-metabolising enzyme that inactivates many drugs. These patients are hypothesised to have greater systemic concentrations of felodipine, a drug which normally has low oral bioavailability secondary to intestinal CYP3A4-mediated metabolism. It serves as a representative for a class containing many medications. DESIGN: A phase I, open-label, single-dose, pharmacokinetic study. SETTING: London, Ontario, Canada. PARTICIPANTS: Patients with coeliac disease (n=47) with positive serology and healthy individuals (n=68). MAIN OUTCOME MEASURES: Patients with coeliac disease-upper gastrointestinal endoscopy and oral felodipine pharmacokinetics study within a 3-week period. Healthy individuals-oral felodipine pharmacokinetics study with water and grapefruit juice. RESULTS: Coeliac stratification categories: Group A (n=15, normal), B+C (n=16, intraepithelial lymphocytosis with/without mild villous blunting) and D (n=16, moderate/severe villous blunting). Groups A, B+C and D had linear trends of increasing felodipine AUC0-8; mean±SEM, 14.4±2.1, 17.6±2.8, 25.7±5.0; p<0.05) and Cmax (3.5±0.5, 4.0±0.6, 6.4±1.1; p<0.02), respectively. Healthy subjects receiving water had lower felodipine AUC0-8 (11.9±0.9 vs 26.9±0.9, p=0.0001) and Cmax (2.9±0.2 vs 7.7±0.2, p=0.0001) relative to those receiving grapefruit juice. CONCLUSIONS: Increased felodipine concentrations in patients with coeliac disease were most probably secondary to decreased small intestinal CYP3A4 expression. Patients with severe coeliac disease and healthy individuals with grapefruit juice had equivalently enhanced effect. Thus, patients with severe coeliac disease would probably experience similarly altered drug response, including overdose toxicity, from many important medications known to be metabolised by CYP3A4. Patients with coeliac disease with severe disease should be considered for other clinical drug management, particularly when there is the potential for serious drug toxicity.


Assuntos
Doença Celíaca/tratamento farmacológico , Felodipino/farmacocinética , Adulto , Idoso , Doença Celíaca/metabolismo , Citrus paradisi/efeitos adversos , Estudos Cross-Over , Citocromo P-450 CYP3A/metabolismo , Relação Dose-Resposta a Droga , Felodipino/administração & dosagem , Felodipino/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Adulto Jovem
5.
Int J Surg Case Rep ; 66: 53-57, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31812122

RESUMO

INTRODUCTION: Duodenal necrosis is a rare complication of acute pancreatitis but can occur given the shared blood supply to the head of the pancreas and the duodenum. PRESENTATION OF CASE: A 55-year-old male presented with acute-on-chronic pancreatitis and a duodenal hematoma. The hematoma expanded to occlude the biliary tree and, shortly after, the duodenum necrosed and perforated. The patient required an emergent pancreaticoduodenectomy performed in two stages. DISCUSSION: Surgical management is complex and a difficult challenge for a general surgeon. Many advocate for wide drainage to create a controlled fistula using a malecot through the wall defect/separate duodenotomy/a retrograde jejunostomy tube. This case represents an extreme variation on this issue which was best managed by definitive resection given the extent of the necrosis. CONCLUSION: This case report demonstrates that duodenal hematoma and necrosis should be recognized as part of the spectrum of consequences of acute pancreatitis. General surgeons should have a surgical approach to this complication whether that be diversion or definitive resection.

6.
Hum Pathol ; 90: 70-79, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31121192

RESUMO

The treatment for colorectal cancer is largely surgical followed by adjuvant chemotherapy in high-risk cases. In patients with stage II cancer, there is no clear benefit for chemotherapy, and the current tools for assessment of risk are inadequate. A recent study identified that colorectal cancer with a gene signature similar to undifferentiated colonic stem cells was associated with a worse outcome. It was later shown that loss of CDX2 detected by immunohistochemistry (IHC) alone resulted in a worse prognosis and that this could be used to predict patients who would benefit from chemotherapy. Having observed that CDX2 expression can be patchy, we elected to validate these prior results for clinical practice using whole-slide IHC. The pathology of all cases was reviewed, and 3 blocks were selected for CDX2 IHC. We also expanded the panel beyond CDX2 to assess whether other markers in the gene signature including CDX1, Muc2, GPX2, and villin could better predict outcome. Among 210 cases, CDX2 expression was diffusely lost in 11% and focally lost in 23% of cases. There was no difference in survival based on CDX2 expression, but Muc2 loss was associated with reduced survival (hazard ratio, 3.32; 95% confidence interval, 1.20 to 9.20). No significant differences in outcome were identified based on CDX1, GPX2, or villin expression. In keeping with this, assessment of The Cancer Genome Atlas gene expression data demonstrated that decreased Muc2 expression was associated with reduced overall survival. Our results with whole-slide IHC are different from the previous studies and caution against the use of CDX2 in isolation as a prognostic marker in clinical practice. We have identified that loss of Muc2 is associated with reduced survival. This supports the use of the colonic differentiation gene expression signature to identify high-risk patients but cautions against the use of any one IHC-based marker in isolation.


Assuntos
Adenocarcinoma/mortalidade , Biomarcadores Tumorais/metabolismo , Fator de Transcrição CDX2/metabolismo , Neoplasias do Colo/mortalidade , Mucina-2/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de Sobrevida
7.
Dis Colon Rectum ; 61(6): 686-691, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29722727

RESUMO

BACKGROUND: Total mesorectal excision is the standard of care for patients with rectal cancer. Pathological evaluation of the quality of the total mesorectal excision specimen is an important prognostic factor that correlates with local recurrence, but is potentially subjective. OBJECTIVE: This study aimed to determine the degree of variation in grading, both between assessors and between fresh and formalin-fixed specimens. DESIGN: Raters included surgeons, pathologists, pathology residents, pathologists' assistants, and pathologists' assistant trainees. Specimens were assessed by up to 6 raters in the fresh state and by 2 raters postfixation. Four parameters were evaluated: mesorectal bulk, surface regularity, defects, and coning. Interrater agreement was measured using ordinal α-values. SETTING: The study was conducted at a single academic center. MAIN OUTCOME MEASURES: The primary outcome was agreement between individuals when grading total mesorectal excision specimens. RESULTS: A total of 37 total mesorectal excision specimens were assessed. Reliability between all raters for fresh specimens for mesorectal bulk, surface regularity, defects, coning, and overall grade were 0.85, 0.85, 0.92, 0.84, and 0.91. When compared with all raters, pathologists and residents had higher agreement and pathologists and surgeons had lower agreement. Ordinal α-values comparing pathologist and pathologist's assistant agreement for overall grade were similar pre- and postfixation (0.78 vs 0.80), but agreement for assessing defects decreased postfixation. Among pathologists' assistants, agreement was higher when grading specimens postfixation than when grading fresh specimens. LIMITATIONS: Assessment bias may have occurred because of the greater number of pathologists' assistants participating than the number of residents and pathologists. CONCLUSIONS: The results indicate good interrater agreement for the assessment of overall grade, with defects showing the best interrater agreement in fresh specimens. Although total mesorectal excision specimens may be consistently graded postfixation, the assessment of defects postfixation may be less reliable. This study highlights the need for additional knowledge-transfer activities to ensure consistency and accurate grading of total mesorectal excision specimens. See Video Abstract at http://links.lww.com/DCR/A497.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/normas , Gradação de Tumores/métodos , Patologistas/estatística & dados numéricos , Neoplasias Retais/cirurgia , Canadá/epidemiologia , Humanos , Recidiva Local de Neoplasia/prevenção & controle , Prognóstico , Neoplasias Retais/patologia , Reprodutibilidade dos Testes , Taxa de Sobrevida
8.
Hum Pathol ; 67: 45-53, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28716438

RESUMO

Venous invasion (VI) is an independent predictor of hematogenous metastasis and mortality in colorectal cancer (CRC) yet remains widely underreported. Its detection may require recognition of subtle morphologic clues, which at times are only unmasked with an elastin stain. This study evaluates the impact of a knowledge transfer initiative (KTI) on VI detection in a "real-world" pathology practice setting. Following participation in an interobserver variability study of VI detection (Kirsch et al, 2013), 12 participants received educational materials highlighting key issues in VI detection. Eighteen months later, participants were invited to submit pathology reports from all CRC resections signed out 18 months prior to and 18 months following the KTI (n = 266 and n = 244, respectively). Nine pathologists participated. Reports were reviewed for VI and other established prognostic factors. Numbers of elastin stains and tumor-containing blocks were also recorded. Comparative analyses were adjusted for baseline differences in tumor, lymph node, and metastasis stage; tumor location; use of neoadjuvant therapy; and number of tumor-containing blocks. VI detection increased significantly post-KTI versus pre-KTI (39.3% versus 18.4%, adjusted odds ratio [OR] 2.86 [1.91-4.28], P < .001). Increased VI detection post-KTI was observed in both stage II (31.8% versus 12.5%, adjusted OR 3.27 [1.45-7.42], P = .004) and stage III CRC (62.4% versus 28.2%, adjusted OR 4.23 [2.37-7.55], P < .001). All pathologists demonstrated increased VI detection post-KTI. Use of elastin stains was significantly higher post-KTI versus pre-KTI (61.5% versus 5.3% of cases respectively, P < .001). This study demonstrates the effectiveness of knowledge transfer in increasing VI detection in routine pathology practice.


Assuntos
Neoplasias Colorretais/patologia , Educação Médica Continuada/métodos , Capacitação em Serviço/métodos , Patologistas/educação , Patologia Clínica/educação , Veias/patologia , Biomarcadores Tumorais/análise , Biópsia , Competência Clínica , Neoplasias Colorretais/química , Neoplasias Colorretais/terapia , Elastina/análise , Humanos , Invasividade Neoplásica , Estadiamento de Neoplasias , Variações Dependentes do Observador , Ontário , Valor Preditivo dos Testes , Reprodutibilidade dos Testes , Coloração e Rotulagem/métodos , Veias/química
9.
Front Med (Lausanne) ; 3: 32, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27556025

RESUMO

BACKGROUND AND AIMS: A short-interval, two-stage approach termed associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) increases the number of patients with extensive malignant disease of the liver and a small future liver remnant (FLR) that can undergo liver resection. While this approach results in accelerated liver hypertrophy of the FLR, it remains unknown whether this phenomenon is restricted to liver parenchymal cells. In the current study, we evaluated whether ALPPS alters the immunological composition of the deportalized lobe (DL) and the FLR. METHODS: In this prospective, single-center study, liver tissue from the DL and the FLR were collected intra-operatively from adult patients undergoing ALPPS for their liver metastases. The extent of hypertrophy of the FLR was determined by volumetric helical computed tomography. Flow cytometry and histological analyses were conducted on liver tissues to compare the frequency of several immune cell subsets, and the architecture of the liver parenchyma between both stages of ALPPS. RESULTS: A total of 12 patients completed the study. Histologically, we observed a patchy peri-portal infiltration of lymphocytes within the DL, and a significant widening of the liver cords within the FLR. Within the DL, there was a significantly higher proportion of B cells and CD4(+) T cells as well innate-like lymphocytes, namely mucosa-associated invariant T (MAIT) cells and natural killer T (NKT) cells following ALPPS. In contrast, the frequency of all evaluated immune cell types remained relatively constant in the FLR. CONCLUSION: Our results provide the first description of the immunological composition of the human liver following ALPPS. We show that following the ALPPS procedure, while the immune composition of the FLR remains relatively unchanged, there is a moderate increase in several immune cell populations in DL. Overall, our results support the continued utilization of the ALPPS procedure.

10.
Histopathology ; 66(7): 1003-9, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25393329

RESUMO

AIMS: Inflammatory oesophageal pseudotumours are rare lesions, thought to be reactive. Due to marked atypia of the stromal cells, these can be misdiagnosed as malignancies. The objective of this study was to characterize histological and immunohistochemical features of a series of inflammatory pseudotumours of the oesophagus. METHODS AND RESULTS: We present 12 cases of inflammatory oesophageal pseudotumours, occurring in seven females and five males, with a mean age of 57.3 years. Clinical presentations were variable; dysphagia, abdominal pain and weight loss and upper gastrointestinal bleed. In a majority of the cases, nodules or masses in the distal oesophagus were identified at endoscopy. Microscopically, the lamina propria in all 12 cases contained inflammation and granulation tissue. Ten of 12 cases showed mucosal ulceration and 11 of 12 cases had acutely inflamed epithelium. Markedly atypical pleomorphic stromal cells with prominent nucleoli were identified in all 12 cases. Immunohistochemistry showed uniform positivity for vimentin in 11 of 11 cases, and two of seven cases demonstrated weak focal positivity for smooth muscle actin. The cells were negative for all other markers. CONCLUSIONS: Reactive oesophageal lesions can show marked nuclear atypia in stromal fibroblasts/myofibroblasts, which are easily mistaken for malignancies. Pathologists must consider the diagnosis of an inflammatory pseudotumour if stromal atypia is present in an inflammatory background.


Assuntos
Biomarcadores Tumorais/metabolismo , Doenças do Esôfago/patologia , Esôfago/patologia , Granuloma de Células Plasmáticas/patologia , Vimentina/metabolismo , Adulto , Idoso , Epitélio/patologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
11.
J Clin Pathol ; 67(9): 781-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25004943

RESUMO

AIMS: Following the introduction of colorectal cancer screening programmes throughout Canada, it became necessary to standardise the diagnosis of colorectal adenomas. Canadian guidelines for standardised reporting of adenomas were developed in 2011. The aims of the present study were (a) to assess interobserver variability in the classification of dysplasia and architecture in adenomas and (b) to determine if interobserver variability could be improved by the adoption of criteria specified in the national guidelines. METHODS: An a priori power analysis was used to determine an adequate number of cases and participants. Twelve pathologists independently classified 40 whole-slide images of adenomas according to architecture and dysplasia grade. Following a wash-out period, participants were provided with the national guidelines and asked to reclassify the study set. RESULTS: At baseline, there was moderate interobserver agreement for architecture (K=0.4700; 95% CI 0.4427 to 0.4972) and dysplasia grade (K=0.5680; 95% CI 0.5299 to 0.6062). Following distribution of the guidelines, there was improved interobserver agreement in assessing architecture (K=0.5403; 95% CI 0.5133 to 0.5674)). For dysplasia grade, overall interobserver agreement remained moderate but decreased significantly (K=0.4833; 95% CI 0.4452 to 0.5215). Half of the cases contained high-grade dysplasia (HGD). Two pathologists diagnosed HGD in ≥75% of cases. CONCLUSIONS: The improvement in interobserver agreement in classifying adenoma architecture suggests that national guidelines can be useful in disseminating knowledge, however, the variability in the diagnosis of HGD, even following guideline review suggests the need for ongoing knowledge-transfer exercises.


Assuntos
Adenoma/patologia , Pólipos Adenomatosos/patologia , Pólipos do Colo/patologia , Neoplasias Colorretais/patologia , Patologia Clínica/normas , Canadá , Fidelidade a Diretrizes , Humanos , Gradação de Tumores , Variações Dependentes do Observador , Guias de Prática Clínica como Assunto , Valor Preditivo dos Testes , Reprodutibilidade dos Testes
12.
PLoS One ; 8(4): e60253, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23585833

RESUMO

We have successfully delivered a reactive alkylating agent, chlorambucil (Cbl), to the mitochondria of mammalian cells. Here, we characterize the mechanism of cell death for mitochondria-targeted chlorambucil (mt-Cbl) in vitro and assess its efficacy in a xenograft mouse model of leukemia. Using a ρ° cell model, we show that mt-Cbl toxicity is not dependent on mitochondrial DNA damage. We also illustrate that re-targeting Cbl to mitochondria results in a shift in the cell death mechanism from apoptosis to necrosis, and that this behavior is a general feature of mitochondria-targeted Cbl. Despite the change in cell death mechanisms, we show that mt-Cbl is still effective in vivo and has an improved pharmacokinetic profile compared to the parent drug. These findings illustrate that mitochondrial rerouting changes the site of action of Cbl and also alters the cell death mechanism drastically without compromising in vivo efficacy. Thus, mitochondrial delivery allows the exploitation of Cbl as a promiscuous mitochondrial protein inhibitor with promising therapeutic potential.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Peptídeos Penetradores de Células/química , Clorambucila/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Leucemia/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , Animais , Antineoplásicos Alquilantes/síntese química , Apoptose/efeitos dos fármacos , Clorambucila/síntese química , Reagentes de Ligações Cruzadas/química , DNA Mitocondrial , Células HeLa , Humanos , Leucemia/metabolismo , Leucemia/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Necrose/patologia , Espécies Reativas de Oxigênio/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
13.
J Dig Dis ; 14(5): 238-43, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23419044

RESUMO

OBJECTIVE: To identify risk factors, clinical features and complications in patients with ischemic colitis (IC). METHODS: All patients diagnosed with biopsy proven IC within a 2-year period were identified; clinical data were retrospectively collected and subsequently analyzed. RESULTS: In total, 72 IC patients with a mean age of 68 years were included in this study. Among them, 18 (25.0%) were younger than 65 years with a female predominance. One-third of the patients was found to be without vascular risk factors, and 8 patients met the criteria for irritable bowel syndrome. No history of oral contraceptives or hormonal replacement therapy use could be found among the women diagnosed with IC. Over a mean duration of follow-up of 9.5 months (range 0-65 months), the rate of recurrent disease was 16.7%, while only 2 (2.8%) patients developed extra intestinal vascular sequelae. Statistical analysis identified a history of atrial fibrillation and the use of furosemide to be the only significant predictors of a poor outcome, while coronary artery disease and chronic renal failure predicted recurrence and low platelet count predicted stricture formation. CONCLUSIONS: Although most patients with IC are elderly and have conventional vascular risk factors, it should also be considered in young patients without vascular risk factors, especially in women, who may have an atypical distribution of the disease. Severe complications and extraintestinal vascular sequelae are rare, however, residual gastrointestinal complaints and recurrent disease are relatively common and there are no reliable predictors of the outcome.


Assuntos
Colite Isquêmica/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Colite Isquêmica/etiologia , Colite Isquêmica/terapia , Colonoscopia , Feminino , Seguimentos , Humanos , Obstrução Intestinal/etiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Recidiva , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Adulto Jovem
14.
Am J Surg Pathol ; 37(2): 200-10, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23108018

RESUMO

Venous invasion (VI) is an independent prognostic indicator in colorectal cancer and may prompt consideration for adjuvant chemotherapy in patients with stage II tumors. Recent evidence suggests that VI is underreported in colorectal cancer and that detection may be enhanced by an elastin stain. This study aimed (1) to determine the impact of an elastin stain on VI detection and on interobserver agreement between gastrointestinal (GI) and non-GI pathologists, and (2) to identify factors associated with increased VI detection. Forty hematoxylin and eosin (H&E)-stained slides were circulated to 6 GI and 6 non-GI pathologists who independently assessed the VI status as positive, negative, or equivocal. Six weeks later, 40 corresponding Movat-stained slides were recirculated together with the original H&E slides and reassessed for VI status. Detection of VI was >2-fold higher with a Movat stain compared with an H&E stain alone (46.4% vs. 19.6%, P=0.001). GI pathologists detected VI more frequently than non-GI pathologists on both H&E (30.0% vs. 9.2%, P=0.029) and Movat (58.3% vs. 34.6%, P=0.018) stains. There was higher interobserver agreement in the case of a Movat stain, particularly for extramural VI (H&E: κ=0.23 vs. Movat: κ=0.41). A poststudy survey indicated that GI pathologists and non-GI pathologists applied similar diagnostic criteria but that GI pathologists more frequently applied "orphan arteriole" and "protruding tongue" signs as diagnostic clues to VI. This study confirms that VI is underdetected on H&E and highlights the role of elastin staining in improving VI detection and interobserver agreement. Strategies to improve VI detection are warranted.


Assuntos
Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/patologia , Elastina/metabolismo , Neoplasias Vasculares/patologia , Veias/patologia , Adenocarcinoma/irrigação sanguínea , Neoplasias Colorretais/irrigação sanguínea , Reações Falso-Positivas , Gastroenterologia/normas , Humanos , Invasividade Neoplásica , Estadiamento de Neoplasias , Variações Dependentes do Observador , Patologia Cirúrgica/normas , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Coloração e Rotulagem/métodos , Neoplasias Vasculares/metabolismo , Veias/metabolismo
15.
World J Gastroenterol ; 18(31): 4145-9, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22919246

RESUMO

AIM: To compare the clinical outcome and pathologic features of non-alcoholic steatohepatitis (NASH) patients with hepatocellular carcinoma (HCC) and hepatitic C virus (HCV) patients with HCC (another group in which HCC is commonly seen) undergoing liver transplantation. METHODS: Patients transplanted for HCV and NASH at our institution from January 2000 to April 2011 were analyzed. All explanted liver histology and pre-transplant liver biopsies were examined by two specialist liver histopathologists. Patient demographics, disease free survival, explant liver characteristics and HCC features (tumour number, cumulative tumour size, vascular invasion and differentiation) were compared between HCV and NASH liver transplant recipients. RESULTS: A total of 102 patients with NASH and 283 patients with HCV were transplanted. The incidence of HCC in NASH transplant recipients was 16.7% (17/102). The incidence of HCC in HCV transplant recipients was 22.6% (64/283). Patients with NASH-HCC were statistically older than HCV-HCC patients (P < 0.001). A significantly higher proportion of HCV-HCC patients had vascular invasion (23.4% vs 6.4%, P = 0.002) and poorly differentiated HCC (4.7% vs 0%, P < 0.001) compared to the NASH-HCC group. A trend of poorer recurrence free survival at 5 years was seen in HCV-HCC patients compared to NASH-HCC who underwent a Liver transplantation (P = 0.11). CONCLUSION: Patients transplanted for NASH-HCC appear to have less aggressive tumour features compared to those with HCV-HCC, which likely in part accounts for their improved recurrence free survival.


Assuntos
Carcinoma Hepatocelular/mortalidade , Fígado Gorduroso/mortalidade , Hepatite C/mortalidade , Neoplasias Hepáticas/mortalidade , Fígado/patologia , Biópsia , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/cirurgia , Comorbidade , Fígado Gorduroso/epidemiologia , Fígado Gorduroso/cirurgia , Feminino , Hepatite C/epidemiologia , Hepatite C/cirurgia , Humanos , Estimativa de Kaplan-Meier , Fígado/cirurgia , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
16.
J Surg Res ; 176(2): 614-20, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22221603

RESUMO

BACKGROUND: Tumor necrosis factor-alpha (TNF-α) is a central mediator in the hepatic response to ischemia/reperfusion. Short hairpin RNA (shRNA) has been proven to be an effective means of harnessing the RNA interference pathway in mammalian cells. In the current study, we investigated whether silencing TNF-α gene with shRNA can prevent liver ischemic reperfusion injury (IRI). METHODS: Male BalB/c mice were randomized to TNF-α shRNA, scramble shRNA, or sham operation groups. TNF-α shRNA and scramble shRNA groups were injected 48 h before inducing IRI. IRI was induced via microaneurysm clamps applied to the left hepatic artery and portal vein. Six hours after reperfusion, IRI injury was examined by serum level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST), liver histopathology, MPO, and MDA level, as well as by relative quantities of TNF-α mRNA. RESULTS: TNF-α expression induced by ischemia reperfusion in the liver was significantly suppressed after treatment with TNF-α shRNA compared with the group treated with scramble shRNA (P < 0.001). Mice treated with TNF-α shRNA showed lower peak values of AST and ALT than scramble shRNA treated mice (P < 0.001). On histopathologic slides, mice treated with TNF-α shRNA had significantly less ischemia/reperfusion injury based on Suzuki score than the scramble shRNA group, 3.57 ± 2.30 and 8.83 ± 0.98 respectively (P < 0.001), while the sham group was not significantly different from the TNF-alpha shRNA group, 0 ± 0 and 3.57 ± 2.30, respectively (P = 0.075). Liver tissue MDA levels were significantly lower in mice treated with TNF-α shRNA as compared with the group treated with scramble shRNA (P < 0.01). Immunohistochemical staining for MPO was significantly lower in mice treated with TNF-α shRNA compared with the group treated with shRNA (compared with treated with scramble shRNA group.) CONCLUSIONS: Liver IRI can be minimized through gene silencing of TNF-α. This may represent a novel therapy in the setting of transplantation and in other conditions associated with IRI of the liver.


Assuntos
Terapia Genética/métodos , Fígado/fisiologia , RNA Interferente Pequeno/farmacologia , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/terapia , Fator de Necrose Tumoral alfa/genética , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Regulação para Baixo/genética , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Peroxidase/metabolismo , RNA Interferente Pequeno/genética , Traumatismo por Reperfusão/patologia
17.
JPEN J Parenter Enteral Nutr ; 35(4): 459-64, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21628610

RESUMO

BACKGROUND: Pure oats are safe for most patients with celiac disease, but concerns regarding contamination by other grains limit their consumption. The Canadian Celiac Association recently released guidelines governing the production of pure oats. The objective was to test the safety of a product manufactured under these guidelines. METHODS: Fifteen adults with established, biopsy-confirmed celiac disease of ≥ 1 year duration were challenged with 350 g/wk of pure oats for 12 weeks. Symptom scores, weight, hemoglobin, ferritin, albumin, and tissue transglutaminase (tTG) were assessed at weeks 0, 6, and 12. Duodenal biopsies were obtained before and after oat challenge and assessed based on the modified Marsh-Oberhuber score. Compliance with a gluten-free diet was monitored with random food diaries. RESULTS: Fifteen patients completed the study and were analyzed in intention-to-treat and per-protocol analyses. There were no significant changes in symptom scores, weight, hemoglobin, ferritin, or albumin during oat consumption. The tTG remained negative in all patients, and the histology scores did not significantly change during oat challenge. The only relapse occurred in a patient who became noncompliant with her gluten-free diet. CONCLUSION: The findings support the safety of pure, uncontaminated oats manufactured under Canadian Celiac Association guidelines for patients with celiac disease.


Assuntos
Avena/química , Doença Celíaca/dietoterapia , Qualidade de Produtos para o Consumidor , Idoso , Canadá , Dieta Livre de Glúten , Feminino , Seguimentos , Contaminação de Alimentos/análise , Glutens , Guias como Assunto , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
18.
Hepatobiliary Pancreat Dis Int ; 8(3): 323-5, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19502177

RESUMO

BACKGROUND: Lobular capillary hemangioma (LCH) is a benign vascular tumor that is rare in adults and has never been reported in the liver. This vascular lesion usually presents on the skin or mucous membranes, and predominantly affects children. METHODS: LCH as a large asymptomatic hepatic mass was seen in a 35-year-old female. Imaging and pathologic characteristics of the mass are reviewed, and the relevant literature is also reviewed. RESULTS: A large vascular hepatic lesion was observed in an asymptomatic 35-year-old female. Pathologic examination after surgical resection revealed typical features of LCH. CONCLUSIONS: This is the first case of lobular capillary hemangioma seen as a liver lesion in an adult. Large vascular hepatic lesions pose significant difficulties in discerning benign from potentially malignant conditions. In this report we describe the pitfalls and radiological uncertainties with interpreting vascular lesions of the liver.


Assuntos
Granuloma Piogênico/diagnóstico , Hepatopatias/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Granuloma Piogênico/metabolismo , Granuloma Piogênico/patologia , Granuloma Piogênico/cirurgia , Humanos , Hepatopatias/metabolismo , Hepatopatias/patologia , Hepatopatias/cirurgia , Imageamento por Ressonância Magnética
19.
Am J Surg Pathol ; 32(9): 1367-72, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18763324

RESUMO

Mycophenolate mofetil (MMF) is a commonly used immunosuppressive drug used in the management of transplant recipients. Although gastrointestinal (GI) toxicity is a known complication of MMF, the literature characterizing the pathologic features of MMF in the GI tract is sparse. This study characterizes the pathologic features of MMF toxicity in both the upper and lower GI tract, correlating it with clinical and endoscopic findings. Seventy-five GI biopsies (9 esophageal, 15 gastric, 16 duodenal, 5 ileal, 30 colonic) from 46 transplant recipients from 2002 to 2006 were obtained and assessed for multiple histologic features. Clinical features were recorded for all cases and endoscopic findings. Only MMF patients showed ulcerative esophagitis (5/7 cases) and reactive gastropathy (4/10 cases). Only MMF patients showed graft-versus-host disease (GVHD)-like features in duodenal (4/12 cases) and ileal (1/5 cases) biopsies. GVHD-like changes were seen more frequently among patients on MMF compared with those not on MMF [9 (56%) vs. 2 (14%); P=0.017]. Crypt architectural disarray [12 (75%) vs. 2 (14%); P=0.001], lamina propria edema [9 (56%) vs. 2 (14%); P=0.017], increased lamina propria inflammation [13 (81%) vs. 3 (21%); P=0.001], dilated damaged crypts [7 (44%) vs. 1 (7%); P=0.024], and increased crypt epithelial apoptosis [9 (56%) vs. 2 (14%); P=0.017] were more common with MMF patients compared with non-MMF patients. In conclusion, pathologists should be aware of the potential manifestations of MMF toxicity throughout the GI tract, including ulcerative esophagitis, reactive gastropathy, and GVHD-like features in intestinal biopsies.


Assuntos
Mucosa Gástrica/efeitos dos fármacos , Doença Enxerto-Hospedeiro/induzido quimicamente , Imunossupressores/efeitos adversos , Mucosa Intestinal/efeitos dos fármacos , Ácido Micofenólico/análogos & derivados , Feminino , Mucosa Gástrica/patologia , Rejeição de Enxerto/prevenção & controle , Humanos , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Ácido Micofenólico/efeitos adversos , Transplante de Órgãos
20.
Am J Surg Pathol ; 32(1): 21-9, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18162766

RESUMO

The morphologic distinction between various serrated polyps of the colorectum may be challenging. The distinction between sessile serrated adenoma (SSA) and traditional serrated adenoma (TSA) may be difficult using currently available criteria mostly based on cytologic characteristics. We have evaluated 66 serrated polyps including 29 SSA, 18 TSA, and 19 hyperplastic polyps for overall shape of the polyps, architectural features of individual crypts, the presence of eosinophilic cytoplasm, size and distribution of the proliferation and maturation zones, as well as Ki-67 and CK20 expression. The extent of the expression of CK20 and Ki-67 could not distinguish between the 3 types of serrated polyps, but the distribution of their expression was very helpful and differences were statistically significant. The distribution of Ki-67+ cells was the single most helpful distinguishing feature of the serrated polyp type (P<0.0001, chi test). Hyperplastic polyps had regular, symmetric, and increased Ki-67 expression. SSA had irregular, asymmetric, and highly variable expression of Ki-67. TSA had low Ki-67 expression, which was limited to "ectopic crypts" and admixed tubular adenomalike areas. In serrated polyps, ectopic crypt formation (ECF) defined by the presence of ectopic crypts with their bases not seated adjacent to the muscularis mucosae was nearly exclusive to TSA and was found in all cases, while the presence of cytologic atypia and eosinophilia of the cytoplasm were characteristic, but not limited to TSA. No evidence of ECF, but nevertheless abnormal distribution of proliferation zone was characteristic of SSA, whereas HP had neither. The presence of the ECF defines TSA in a more rigorous fashion than previous diagnostic criteria and also explains the biologic basis of exuberant protuberant growth associated with TSA and the lack of such growth in SSA. Recognition of this phenomenon may also help in exploring the genetic and molecular basis for differences between SSA and TSA, because these architectural abnormalities may well be a reflection of abnormalities in genetically programmed mucosal development.


Assuntos
Adenoma/patologia , Neoplasias Colorretais/patologia , Pólipos Intestinais/patologia , Adenoma/metabolismo , Neoplasias Colorretais/metabolismo , Diagnóstico Diferencial , Humanos , Imuno-Histoquímica , Pólipos Intestinais/metabolismo , Queratina-20/biossíntese , Antígeno Ki-67/biossíntese
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