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1.
Clin Exp Gastroenterol ; 12: 219-229, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31190949

RESUMO

Purpose: The incidence of esophageal adenocarcinoma (EAC) has increased by 700% in Western countries over the last 30 years. Although clinical guidelines call for endoscopic surveillance for EAC among high-risk populations, fewer than 5% of new EAC patients are under surveillance at the time of diagnosis. We studied the accuracy of combined cytopathology and MUC2 immunohistochemistry (IHC) for screening of Intestinal Metaplasia (IM), dysplasia and EAC, using specimens collected from the EsophaCap swallowable encapsulated cytology sponge from Canada and United States. Patients and methods: By comparing the EsophaCap cytological diagnosis with concurrent endoscopic biopsies performed on the same patients in 28 cases, we first built up the cytology diagnostic categories and criteria. Based on these criteria, 136 cases were evaluated by both cytology and MUC2 IHC with blinded to patient biopsy diagnosis. Results: We first set up categories and criteria for cytological diagnosis of EscophaCap samples. Based on these, we divided our evaluated cytological samples into two groups: non-IM group and IM or dysplasia or adenocarcinoma group. Using the biopsy as our gold standard to screen IM, dysplasia and EAC by combined cytology and MUC2 IHC, the sensitivity and specificity were 68% and 91%, respectively, which is in the range of clinically useful cytological screening tests such as the cervical Pap smear. Conclusions: Combined EsophaCap cytology and MUC2 IHC could be a good screening test for IM and Beyond.

2.
JAMA Oncol ; 5(7): 961-966, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30973610

RESUMO

Importance: Chemoradiotherapy (CRT), followed by surgery, is the recommended approach for stage II and III rectal cancer. While CRT decreases the risk of local recurrence, it does not improve survival and leads to poorer functional outcomes than surgery alone. Therefore, new approaches to better select patients for CRT are important. Objective: To conduct a phase 2 study to evaluate the safety and feasibility of using magnetic resonance imaging (MRI) criteria to select patients with "good prognosis" rectal tumors for primary surgery. Design, Setting, and Participants: Prospective nonrandomized phase 2 study at 12 high-volume colorectal surgery centers across Canada. From September 30, 2014, to October 21, 2016, a total of 82 patients were recruited for the study. Participants were patients newly diagnosed as having rectal cancer with MRI-predicted good prognosis rectal cancer. The MRI criteria for good prognosis tumors included distance to the mesorectal fascia greater than 1 mm; definite T2, T2/early T3, or definite T3 with less than 5 mm of extramural depth of invasion; and absent or equivocal extramural venous invasion. Interventions: Patients with rectal cancer with MRI-predicted good prognosis tumors underwent primary surgery. Main Outcomes and Measures: The primary outcome was the proportion of patients with a positive circumferential resection margin (CRM) rate. Assuming a 10% baseline probability of a positive CRM, a sample size of 75 was estimated to yield a 95% CI of ±6.7%. Results: Eighty-two patients (74% male) participated in the study. The median age at the time of surgery was 66 years (range, 37-89 years). Based on MRI, most tumors were midrectal (65% [n = 53]), T2/early T3 (60% [n = 49]), with no suspicious lymph nodes (63% [n = 52]). On final pathology, 91% (n = 75) of tumors were T2 or greater, 29% (n = 24) were node positive, and 59% (n = 48) were stage II or III. The positive CRM rate was 4 of 82 (4.9%; 95% CI, 0.2%-9.6%). Conclusions and Relevance: The use of MRI criteria to select patients with good prognosis rectal cancer for primary surgery results in a low rate of positive CRM and suggests that CRT may not be necessary for all patients with stage II and III rectal cancer. Trial Registration: ISRCTN.com identifier: ISRCTN05107772.

3.
Gastroenterology ; 142(5): 1160-71, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22333951

RESUMO

BACKGROUND & AIMS: The Helicobacter pylori toxin vacuolating cytotoxin (VacA) promotes gastric colonization, and its presence (VacA(+)) is associated with more-severe disease. The exact mechanisms by which VacA contributes to infection are unclear. We previously found that limited exposure to VacA induces autophagy of gastric cells, which eliminates the toxin; we investigated whether autophagy serves as a defense mechanism against H pylori infection. METHODS: We investigated the effect of VacA on autophagy in human gastric epithelial cells and primary gastric cells from mice. Expression of p62, a marker of autophagy, was also assessed in gastric tissues from patients infected with toxigenic (VacA(+)) or nontoxigenic strains. We analyzed the effect of VacA on autophagy in peripheral blood monocytes obtained from subjects with different genotypes of ATG16L1, which regulates autophagy. We performed genotyping for ATG16L1 in 2 cohorts of infected and uninfected subjects. RESULTS: Prolonged exposure of human gastric epithelial cells and mouse gastric cells to VacA disrupted induction of autophagy in response to the toxin, because the cells lacked cathepsin D in autophagosomes. Loss of autophagy resulted in the accumulation of p62 and reactive oxygen species. Gastric biopsy samples from patients infected with VacA(+), but not nontoxigenic strains of H pylori, had increased levels of p62. Peripheral blood monocytes isolated from individuals with polymorphisms in ATG16L1 that increase susceptibility to Crohn's disease had reduced induction of autophagy in response to VacA(+) compared to cells from individuals that did not have these polymorphisms. The presence of the ATG16L1 Crohn's disease risk variant increased susceptibility to H pylori infection in 2 separate cohorts. CONCLUSIONS: Autophagy protects against infection with H pylori; the toxin VacA disrupts autophagy to promote infection, which could contribute to inflammation and eventual carcinogenesis.


Assuntos
Autofagia/fisiologia , Proteínas de Bactérias/fisiologia , Infecções por Helicobacter/etiologia , Helicobacter pylori , Alelos , Animais , Proteínas de Bactérias/genética , Catepsina D/fisiologia , Doença de Crohn/etiologia , Doença de Crohn/genética , Genótipo , Humanos , Imunidade Inata , Camundongos , Fagossomos/fisiologia
4.
Urology ; 69(5): 810-2, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17482909

RESUMO

OBJECTIVES: Ketamine hydrochloride is an N-methyl-D-aspartic acid receptor antagonist used as an anesthetic agent in human and veterinary procedures. Increasingly, it is being used as a recreational drug. Recreational ketamine users have anecdotally reported increased lower urinary tract symptoms while using the substance. METHODS: We describe a series of 9 patients, all of whom were daily ketamine users, who presented with severe dysuria, frequency, urgency, and gross hematuria. Investigations, including urine culture, microscopy, and cytology, in addition to computed tomography, cystoscopy, and bladder biopsies, were performed to identify a relationship between recreational ketamine use and these symptoms. RESULTS: The urine cultures were sterile in all cases. Computed tomography revealed marked thickening of the bladder wall, a small capacity, and perivesicular stranding, consistent with severe inflammation. At cystoscopy, all patients had severe ulcerative cystitis. Biopsies in 4 patients revealed epithelial denudation and inflammation with a mild eosinophilic infiltrate. Cessation of ketamine use, with the addition of pentosan polysulfate, appeared to provide some symptomatic relief. CONCLUSIONS: This case series has described a new clinical entity of severe ulcerative cystitis as a result of chronic ketamine use. As illicit ketamine becomes more easily available, ulcerative cystitis and potential long-term bladder sequelae related to its use may be a more prevalent problem confronting urologists.


Assuntos
Cistite/induzido quimicamente , Cistite/patologia , Ketamina/efeitos adversos , Poliéster Sulfúrico de Pentosana/efeitos adversos , Adulto , Biópsia por Agulha , Cistoscopia , Feminino , Seguimentos , Humanos , Ketamina/administração & dosagem , Masculino , Poliéster Sulfúrico de Pentosana/administração & dosagem , Recidiva , Amostragem , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Úlcera/induzido quimicamente , Úlcera/patologia , Urinálise
5.
Pathol Res Pract ; 202(12): 837-47, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17064855

RESUMO

The literature on gastrointestinal stromal tumors (GISTs) has rapidly expanded and has demonstrated how scientific advancements in diagnosis can revolutionize the understanding of disease, while paving the way for effective treatment. While KIT (CD117) immunohistochemistry has established our definition of GISTs, molecular genetics continue to refine it. Elucidation of the aberrant receptor tyrosine kinase (RTK) model of GIST pathogenesis through mutations in c-kit and platelet-derived growth factor alpha PDGFRalpha proto-oncogenes has been prerequisite to the use of imatinib mesylate (STI571, Gleevec; Novartis, Switzerland), a molecular inhibitor of several tyrosine kinases, in the treatment of GISTs. In addition to providing a means for effective treatment, clarification of the molecular pathology of GISTs may potentially offer a new classification of these tumors by correlating genotype with histological, immunohistochemical, and clinical phenotype. This article seeks to review current knowledge of GISTs, offering a practical guide to their diagnosis and describing current epidemiological, molecular biological, and therapeutic aspects.


Assuntos
Tumores do Estroma Gastrointestinal/patologia , Leiomioma/patologia , Antineoplásicos/uso terapêutico , Benzamidas , Biomarcadores Tumorais/análise , Tumores do Estroma Gastrointestinal/química , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/terapia , Humanos , Mesilato de Imatinib , Leiomioma/química , Leiomioma/tratamento farmacológico , Leiomioma/genética , Mutação , Piperazinas/uso terapêutico , Pirimidinas/uso terapêutico , Medição de Risco , Células Estromais/patologia
6.
Nat Clin Pract Gastroenterol Hepatol ; 3(4): 229-33; quiz following 233, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16582965

RESUMO

BACKGROUND: A 65-year-old white Mediterranean male with a 10-year history of intermittent anemia, who was otherwise completely asymptomatic, was referred to our hospital in March 2004. He had a medical history of beta thalassemia and fecal occult blood tests had occasionally been positive. INVESTIGATIONS: Fecal occult blood test, laboratory investigations, esophagogastroduodenoscopy, colonoscopy with retrograde ileoscopy, mesenteric angiography, small-bowel series, CT scan of the abdomen and pelvis, Meckel's scan, and capsule endoscopy. Laparoscopic surgery followed by macroscopic and microscopic histopathologic examination of samples obtained during the procedure. DIAGNOSIS: Crohn's disease of the small bowel. MANAGEMENT: Laparoscopic segmental small-bowel resection with end-to-end anastomosis. Postsurgical treatment with Pentasa 4 g a day.


Assuntos
Anemia Ferropriva/etiologia , Doença de Crohn/diagnóstico , Idoso , Anti-Inflamatórios não Esteroides/uso terapêutico , Colonoscopia , Doença de Crohn/complicações , Doença de Crohn/patologia , Doença de Crohn/cirurgia , Diagnóstico Diferencial , Endoscopia do Sistema Digestório , Humanos , Mucosa Intestinal/patologia , Intestino Delgado/patologia , Masculino , Mesalamina/uso terapêutico , Sangue Oculto , Talassemia beta/epidemiologia
7.
Hum Pathol ; 37(3): 373-6, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16613334

RESUMO

Autoimmune enteropathy (AIE) is a relatively rare condition found most frequently in children. It presents with persistent watery diarrhea and malabsorption and may require total parenteral nutrition for nutritional support. Rare cases have been reported in adults. On histology, the small intestinal villi are flattened but lack the intraepithelial lymphocytosis of celiac disease. In children and rarely in adults, some cases are linked to the IPEX syndrome (Immune dysregulation, Polyendocrinopathy, Enteropathy, X-linked inheritance). We report a 21-year-old man who presented with chronic persistent diarrhea for 4 years. The duodenal biopsies showed villous blunting, chronic inflammation, and decreased to absent goblet cells, Paneth cells, and endocrine cells by histology and electron microscopy. These changes are consistent with an AIE with involvement of non-enterocyte populations. Pathologists must be aware of the possibility of AIE in adults and consider it in the differential diagnosis of duodenitis, intraepithelial lymphocytosis, and small bowel villous flattening.


Assuntos
Doenças Autoimunes/patologia , Diarreia/patologia , Células Enteroendócrinas/patologia , Enteropatias/patologia , Intestino Delgado/patologia , Celulas de Paneth/patologia , Adulto , Doenças Autoimunes/imunologia , Doenças Autoimunes/terapia , Diarreia/imunologia , Diarreia/terapia , Glucocorticoides/uso terapêutico , Humanos , Enteropatias/imunologia , Enteropatias/terapia , Intestino Delgado/imunologia , Masculino , Nutrição Parenteral Total , Prednisona/uso terapêutico , Resultado do Tratamento
8.
Gastrointest Endosc ; 62(3): 452-6, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16111974

RESUMO

BACKGROUND: Appendiceal mucoceles are uncommon cystic neoplasms characterized by distension of the appendiceal lumen with mucus. There have been no reported series of colonoscopically diagnosed mucoceles with clinicopathologic correlation. METHODS: A retrospective review of colonoscopies performed at our institution over the past 14 years was undertaken with patient demographics, clinical data, surgical outcomes, and histopathology obtained from hospital records. OBSERVATIONS: Seven patients (6 women) with mucocele of the appendix were identified at colonoscopy. Three had complained of right lower quadrant pain. All 7 patients underwent surgical resection. Histopathology demonstrated mucinous cystadenoma in all. No cases revealed carcinoma, and there have been no deaths related to the mucocele. CONCLUSIONS: Appendiceal mucoceles may be recognized at colonoscopy as a smooth bulbous submucosal lesion of the cecum with an impression formed by the appendiceal orifice. Recognition at colonoscopy is important because it enables accurate diagnosis and directs management. Surgery is recommended in all cases given the risk of malignancy or perforation with resultant pseudomyxoma peritonei.


Assuntos
Doenças do Ceco/diagnóstico , Colonoscopia/métodos , Mucocele/diagnóstico , Adulto , Idoso , Apendicectomia/métodos , Apêndice/patologia , Apêndice/cirurgia , Biópsia por Agulha , Doenças do Ceco/epidemiologia , Doenças do Ceco/cirurgia , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Incidência , Mucosa Intestinal/patologia , Masculino , Pessoa de Meia-Idade , Mucocele/epidemiologia , Mucocele/cirurgia , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Resultado do Tratamento
9.
Am J Gastroenterol ; 100(3): 685-94, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15743369

RESUMO

BACKGROUND AND AIMS: Capsule endoscopy (CE) has been increasingly used for diagnosing diseases of the small bowel. It is an attractive technique for assessing celiac disease (CD) because it is noninvasive and provides a close and magnified view of the mucosa of the entire small bowel. In this study, we evaluated the accuracy of CE and interobserver agreement in recognizing villous atrophy (VA) using histopathology as the reference. We also explored the extent of small bowel involvement with CD and the relationship between the length of the affected bowel and the clinical presentation. METHODS: Ten CD patients with histologically proven VA and the same number of controls were subjected to CE. Four, blinded to histology findings, investigators (two with and two without prestudy CE experience) were asked to diagnose VA on CE images. RESULTS: Based on assessment of all four investigators, the overall sensitivity, specificity, PPV, and NPV of CE in diagnosing VA were 70%, 100%, 100%, and 77%, respectively. The sensitivity and the specificity of the test was 100% when the reports of experienced capsule endoscopists only were analyzed. The interobserver agreement was perfect (kappa= 1.0) between investigators with prestudy CE experience and poor (kappa= 0.2) between the investigators who had limited prestudy exposure to CE. Celiac patients with extensive small bowel involvement had typical symptoms of malabsorption (diarrhea, weight loss) as opposed to mild and nonspecific symptoms in patients whose disease was limited to the proximal small bowel. CE was tolerated well by all study participants with 95% reporting absence of any discomfort. CONCLUSIONS: Although based on a small sample size, the study suggests that CE may be useful in assessing patients with CD. Familiarity with CE technology appears to be a critical factor affecting the accuracy of the test. Larger studies are warranted to more precisely define the advantages and limitations of CE in CD.


Assuntos
Doença Celíaca/patologia , Endoscopia Gastrointestinal/métodos , Atrofia , Endoscopia Gastrointestinal/normas , Humanos , Mucosa Intestinal/patologia , Variações Dependentes do Observador , Sensibilidade e Especificidade
10.
Am J Physiol Gastrointest Liver Physiol ; 287(3): G599-604, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15331352

RESUMO

In vivo T cell activation by anti-CD3 monoclonal antibody (mAb) results in intestinal damage characterized by loss of villi and epithelial cell apoptosis. The role of the increased interleukin (IL)-10 released during this process is not clear. We assessed the effects of IL-10 on T cell-induced mucosal damage in vivo using IL-10-deficient C57BL/6 [IL-10 knockout (KO)] mice. IL-10 KO and wild-type C57BL/6 mice were injected with anti-CD3 mAb and observed for diarrhea. Changes in serum cytokine levels were measured by ELISA. Histological changes and epithelial cell apoptosis were analyzed on hematoxylin- and eosin-stained tissue sections. Fas expression on intestinal epithelial cells was assessed by flow cytometry analysis of freshly isolated intestinal epithelial cells. Anti-CD3-treated IL-10 KO mice developed more severe diarrhea, a greater loss of intestinal villi, and an increase in the numbers of apoptotic cells in the crypt epithelium. This difference in IL-10 KO mice was associated with an increase in serum tumor necrosis factor-alpha and interferon-gamma levels and with an increase in Fas expression on fresh, isolated, small intestinal epithelial cells. In addition, the enhanced intestinal tissue damage induced by anti-CD3 in IL-10 KO mice was significantly diminished by treatment with recombinant murine IL-10. Therefore, the lack of IL-10 allowed for an increased T cell-induced intestinal tissue damage, and this was associated with an increase in T cell cytokine release and an increase in epithelial cell Fas expression.


Assuntos
Apoptose/efeitos dos fármacos , Interleucina-10/fisiologia , Enteropatias/patologia , Intestinos/patologia , Linfócitos T/fisiologia , Animais , Anticorpos Monoclonais/farmacologia , Temperatura Corporal/genética , Temperatura Corporal/fisiologia , Complexo CD3/imunologia , Citocinas/metabolismo , Células Epiteliais/efeitos dos fármacos , Citometria de Fluxo , Interleucina-10/genética , Interleucina-10/farmacologia , Enteropatias/induzido quimicamente , Enteropatias/mortalidade , Mucosa Intestinal/patologia , Ativação Linfocitária/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Recombinantes/farmacologia , Receptor fas/biossíntese
12.
J Immunol ; 172(3): 1515-23, 2004 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-14734729

RESUMO

The triggering Ag for inflammatory bowel disease and animal models of colitis is not known, but may include gut flora. Feeding OVA to DO11.10 mice with OVA-specific transgenic (Tg) TCR generates Ag-specific immunoregulatory CD4(+) T cells (Treg) cells. We examined the ability of oral Ag-induced Treg cells to suppress T cell-mediated colitis in mice. SCID-bg mice given DO11.10 CD4(+)CD45RB(high) T cells developed colitis, and cotransferring DO11.10 CD45RB(low)CD4(+) T cells prevented CD4(+)CD45RB(high) T cell-induced colitis in the absence of OVA. The induction and prevention of disease by DO11.10 CD4(+) T cell subsets were associated with an increase in endogenous TCRalpha chain expression on Tg T cells. Feeding OVA to SCID-bg mice reconstituted with DO11.10 CD4(+)CD45RB(high) attenuated the colitis in association with increased TGF-beta and IL-10 secretion, and decreased proliferative responses to both OVA and cecal bacteria Ag. OVA feeding also attenuated colitis in SCID-bg mice reconstituted with a mix of BALB/c and DO11.10 CD45RB(high) T cells, suggesting that OVA-induced Treg cells suppressed BALB/c effector cells. The expression of endogenous non-Tg TCR allowed for DO11.10-derived T cells to respond to enteric flora Ag. Furthermore, feeding OVA-induced Treg cells prevented colitis by inducing tolerance in both OVA-reactive and non-OVA-reactive T cells and by inducing Ag-nonspecific Treg cells. Such a mechanism might allow for Ag-nonspecific modulation of intestinal inflammation in inflammatory bowel disease.


Assuntos
Antígenos de Bactérias/imunologia , Colite/prevenção & controle , Tolerância Imunológica , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/biossíntese , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Administração Oral , Transferência Adotiva , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/transplante , Ceco/imunologia , Ceco/microbiologia , Divisão Celular/genética , Divisão Celular/imunologia , Linhagem Celular , Colite/genética , Colite/imunologia , Colite/patologia , Citocinas/biossíntese , Epitopos de Linfócito T/administração & dosagem , Epitopos de Linfócito T/imunologia , Tolerância Imunológica/genética , Imunidade nas Mucosas/genética , Imunofenotipagem , Mucosa Intestinal/imunologia , Mucosa Intestinal/microbiologia , Mucosa Intestinal/patologia , Antígenos Comuns de Leucócito/administração & dosagem , Antígenos Comuns de Leucócito/biossíntese , Antígenos Comuns de Leucócito/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos SCID , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Interleucina-2/biossíntese , Subpopulações de Linfócitos T/transplante
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