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1.
Dig Dis Sci ; 64(10): 2815-2822, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30982210

RESUMO

BACKGROUND: The endoscopic detection of esophageal cancer is suboptimal in both patients referred with dyspeptic symptoms and those enrolled in Barrett's surveillance programs. MCM5 expression in cells collected from gastric fluid may be correlated with the presence of dysplasia or adenocarcinoma. Analysis of this biomarker may improve the detection of cancer. METHODS: Sixty-one patients were enrolled at a single UK referral center. From each patient, 5-10 ml of gastric fluid was aspirated endoscopically. Patients were categorized according to their histology, normal, non-dysplastic Barrett's (NDBE), high-grade dysplastic Barrett's (HGD), and esophageal adenocarcinoma (EAC). All histology was confirmed by Seattle protocol biopsies or endoscopic mucosal resection. Samples were centrifuged, and the cell pellet was lysed. MCM5 expression levels were quantified using a proprietary immunoassay. The mean MCM5 expression was compared between groups by Kruskal-Wallis test. ROC curves were also used to assess diagnostic utility. RESULTS: The mean expression of MCM5 increases as patients progress from a normal esophagus to NDBE, HGD, and EAC (14.4; 49.8; 112.3; and 154.1, respectively). There was a significant difference in the MCM5 expression of patients with a normal esophagus compared to those with EAC (p = 0.04). There was a trend toward higher MCM5 expression in patients with EAC compared to those with NDBE (p = 0.34). MCM5 expression was a fair discriminator (AUC 0.70 [95% CI 0.57-0.83]) between patients without neoplasia (normal and NDBE) and those with early neoplasia (HGD and EAC). CONCLUSION: MCM5 expression in gastric fluid samples can differentiate patients with a histologically normal esophagus compared to those with early adenocarcinoma. Larger, powered studies are needed to assess whether it can be used to differentiate those with HGD from NDBE.


Assuntos
Adenocarcinoma , Esôfago de Barrett , Proteínas de Ciclo Celular/análise , Neoplasias Esofágicas , Suco Gástrico/metabolismo , Lesões Pré-Cancerosas , Adenocarcinoma/diagnóstico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Esôfago de Barrett/diagnóstico , Esôfago de Barrett/metabolismo , Esôfago de Barrett/patologia , Biomarcadores/análise , Biópsia/métodos , Replicação do DNA , Progressão da Doença , Detecção Precoce de Câncer/métodos , Endoscopia do Sistema Digestório/métodos , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Lesões Pré-Cancerosas/diagnóstico , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/patologia
2.
Hum Genet ; 137(9): 723-734, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30167848

RESUMO

Rare variants are thought to contribute to the genetics of inflammatory bowel disease (IBD), which is more common amongst the Ashkenazi Jewish (AJ) population. A family-based approach using exome sequencing of AJ individuals with IBD was employed with a view to identify novel rare genetic variants for this disease. Exome sequencing was performed on 960 Jewish individuals including 513 from 199 multiplex families with up to eight cases. Rare, damaging variants in loci prioritized by linkage analysis and those shared by multiple affected individuals within the same family were identified. Independent evidence of association of each variant with disease was assessed. A number of candidate variants were identified, including in genes involved in the immune system. The ability to achieve statistical significance in independent case/control replication data was limited by power and was only achieved for variants in the well-established Crohn's disease gene, NOD2. This work demonstrates the challenges of identifying disease-associated rare damaging variants from exome data, even amongst a favorable cohort of familial cases from a genetic isolate. Further research of the prioritized rare candidate variants is required to confirm their association with the disease.


Assuntos
Predisposição Genética para Doença , Variação Genética , Doenças Inflamatórias Intestinais/genética , Judeus/genética , Proteína Adaptadora de Sinalização NOD2/genética , Fases de Leitura Aberta , Estudos de Casos e Controles , Feminino , Ligação Genética , Humanos , Masculino , Linhagem , Análise de Sequência de DNA/métodos
3.
Photochem Photobiol Sci ; 15(10): 1227-1238, 2016 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-27501936

RESUMO

In many cancers early intervention involves surgical resection of small localised tumour masses. Inadequate resection leads to recurrence whereas overzealous treatment can lead to organ damage. This work describes production of a HER2 targeting antibody Fab fragment dual conjugated to achieve both real time near-infrared fluorescent imaging and photodynamic therapy. The use of fluorescence emission from a NIR-dye could be used to guide resection of tumour bulk, for example during endoscopic diagnosis for oesophago-gastric adenocarcinoma, this would then be followed by activation of the photodynamic therapeutic agent to destroy untreated localised areas of cancer infiltration and tumour infiltrated lymph nodes. This theranostic agent was prepared from the Fab fragment of trastuzumab initially by functional disulfide re-bridging and site-specific click reaction of a NIR-dye. This was followed by further reaction with a novel pre-activated form of the photosensitiser chlorin e6 with the exposed fragments' lysine residues. Specific binding of the theranostic agent was observed in vitro with a HER2 positive cell line and cellular near-infrared fluorescence was observed with flow cytometry. Specific photo-activity of the conjugates when exposed to laser light was observed with HER2 positive but not HER2 negative cell lines in vitro, this selectivity was not seen with the unconjugated drug. This theranostic agent demonstrates that two different photo-active functions can be coupled to the same antibody fragment with little interference to their independent activities.


Assuntos
Antineoplásicos Imunológicos/farmacologia , Neoplasias/tratamento farmacológico , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Receptor ErbB-2/antagonistas & inibidores , Nanomedicina Teranóstica , Trastuzumab/farmacologia , Antineoplásicos Imunológicos/síntese química , Antineoplásicos Imunológicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias/metabolismo , Neoplasias/patologia , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Receptor ErbB-2/metabolismo , Relação Estrutura-Atividade , Trastuzumab/química , Células Tumorais Cultivadas
4.
Gut ; 64(8): 1192-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25539672

RESUMO

BACKGROUND: Barrett's oesophagus (BE) is a pre-malignant condition leading to oesophageal adenocarcinoma (OAC). Treatment of neoplasia at an early stage is desirable. Combined endoscopic mucosal resection (EMR) followed by radiofrequency ablation (RFA) is an alternative to surgery for patients with BE-related neoplasia. METHODS: We examined prospective data from the UK registry of patients undergoing RFA/EMR for BE-related neoplasia from 2008 to 2013. Before RFA, visible lesions were removed by EMR. Thereafter, patients had RFA 3-monthly until all BE was ablated or cancer developed (endpoints). End of treatment biopsies were recommended at around 12 months from first RFA treatment or when endpoints were reached. Outcomes for clearance of dysplasia (CR-D) and BE (CR-IM) at end of treatment were assessed over two time periods (2008-2010 and 2011-2013). Durability of successful treatment and progression to OAC were also evaluated. RESULTS: 508 patients have completed treatment. CR-D and CR-IM improved significantly between the former and later time periods, from 77% and 56% to 92% and 83%, respectively (p<0.0001). EMR for visible lesions prior to RFA increased from 48% to 60% (p=0.013). Rescue EMR after RFA decreased from 13% to 2% (p<0.0001). Progression to OAC at 12 months is not significantly different (3.6% vs 2.1%, p=0.51). CONCLUSIONS: Clinical outcomes for BE neoplasia have improved significantly over the past 6 years with improved lesion recognition and aggressive resection of visible lesions before RFA. Despite advances in technique, the rate of cancer progression remains 2-4% at 1 year in these high-risk patients. TRIAL REGISTRATION NUMBER: ISRCTN93069556.


Assuntos
Adenocarcinoma/cirurgia , Esôfago de Barrett/cirurgia , Ablação por Cateter/métodos , Neoplasias Esofágicas/cirurgia , Esofagoscopia/métodos , Lesões Pré-Cancerosas , Sistema de Registros , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Progressão da Doença , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento , Reino Unido
5.
Lasers Med Sci ; 28(3): 707-15, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22699800

RESUMO

Photofrin photodynamic therapy (PDT) is a licenced treatment for Barrett's oesophagus (BE) with high-grade dysplasia (HGD) but causes strictures and photosensitivity and complete reversal of dysplasia (CR-HGD) by 50 % at 5 years. 5-Aminolaevulinic acid (ALA) is an alternative treatment with non-randomised data suggesting 85 % CR-HGD and a low risk of side effects. We aimed to compare efficacy and side effect profile between the drugs. A single-centre randomised controlled trial was conducted. Presence of HGD was confirmed on three occasions by two specialist GI pathologists. Stratification was by length of BE and extent of dysplasia. Standard protocols for ALA and Photofrin-PDT were followed. Endoscopic follow-up with 2-cm four-quadrant biopsy was at 6 weeks, 4 months, and then annually. All adverse event data were collected. Sixty four patients were randomised, 34 ALA and 30 Photofrin-PDT. Median follow-up is 24 months. On intention-to-treat analysis, CR-HGD was 16/34 (47 %) with ALA-PDT and 12/30 (40 %) with Photofrin-PDT. The overall cancer incidence was 14 % (9/64). On sub-group log-rank analysis, for BE ≤ 6 cm, CR-HGD was significantly higher with ALA-PDT than Photofrin-PDT (χ(2) =5.39, p=0.02). Strictures and skin photosensitivity were significantly more common after treatment with Photofrin-PDT than ALA-PDT (33 vs. 9 % and 43 vs. 6 %, respectively, p<0.05). The rate of buried glands with either drug was significantly higher post-PDT (48 % of patients) than pre-PDT (20 %). ALA-PDT has a better risk profile than Photofrin-PDT. In patients with BE length ≤ 6 cm, preliminary results show ALA-PDT is associated with significantly higher CR-HGD. In longer segments of BE, neither PDT drug is sufficiently efficacious to warrant routine use.


Assuntos
Ácido Aminolevulínico/uso terapêutico , Esôfago de Barrett/tratamento farmacológico , Éter de Diematoporfirina/uso terapêutico , Fotoquimioterapia/métodos , Adenocarcinoma/etiologia , Adenocarcinoma/patologia , Adenocarcinoma/prevenção & controle , Idoso , Ácido Aminolevulínico/efeitos adversos , Esôfago de Barrett/complicações , Esôfago de Barrett/patologia , Éter de Diematoporfirina/efeitos adversos , Progressão da Doença , Neoplasias Esofágicas/etiologia , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/prevenção & controle , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fotoquimioterapia/efeitos adversos , Fotoquimioterapia/instrumentação , Fármacos Fotossensibilizantes/efeitos adversos , Fármacos Fotossensibilizantes/uso terapêutico , Resultado do Tratamento
7.
Br J Cancer ; 105(8): 1218-23, 2011 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-21934680

RESUMO

BACKGROUND: Dysplasia is a marker of cancer risk in Barrett's oesophagus (BO), but this risk is variable and diagnosis is subject to inter-observer variability. Cancer risk in BO is increased when chromosomal instability is present. Nucleotyping (NT) is a new method that uses high-resolution digital images of nuclei to assess chromatin organisation both quantitatively and qualitatively. We aimed to evaluate NT as a marker of dysplasia in BO and compare with image cytometric DNA analysis (ICM). METHODS: In all, 120 patients with BO were studied. The non-dysplastic group (n=60) had specialised intestinal metaplasia only on two consecutive endoscopies after 51 months median follow-up (IQR=25-120 months). The dysplastic group (n=60) had high-grade dysplasia or carcinoma in situ. The two groups were then randomly assigned to a training set and a blinded test set in a 1:1 ratio. Image cytometric DNA analysis and NT was then carried out on Feulgen-stained nuclear monolayers. RESULTS: The best-fit model for NT gave a correct classification rate (CCR) for the training set of 83%. The test set was then analysed using the same textural features and yielded a CCR of 78%. Image cytometric DNA analysis alone yielded a CCR of 73%. The combination of ICM and NT yielded a CCR of 84%. CONCLUSION: Nucleotyping differentiates dysplastic and non-dysplastic BO, with a greater sensitivity than ICM. A combination score based on both techniques performed better than either test in isolation. These data demonstrate that NT/ICM on nuclear monolayers is a very promising single platform test of genomic instability, which may aid pathologists in the diagnosis of dysplasia and has potential as a biomarker in BO.


Assuntos
Esôfago de Barrett/patologia , DNA/genética , Esôfago de Barrett/genética , Humanos , Poliploidia
8.
Endoscopy ; 43(7): 627-30, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21717379

RESUMO

Endoscopic radiofrequency ablation (RFA) is an effective treatment for high-grade dysplasia in Barrett's esophagus in ablation-naïve patients, but no studies have evaluated its use in patients in whom ablative therapy has previously failed. We describe 14 patients with residual high-grade dysplasia following aminolevulinic acid or Photofrin (porfimer sodium) photodynamic therapy (PDT). An overall complete reversal of dysplasia was achieved in 86 % with a combination of RFA and rescue endoscopic mucosal resection. The median total follow-up is 19 months. The rate of strictures was 7 % (1/14) and there was a low rate of buried glands (0.5 % follow-up biopsies). These data suggest RFA is both safe and effective for eradication of high-grade dysplasia in patients in whom PDT has failed.


Assuntos
Esôfago de Barrett/cirurgia , Ablação por Cateter , Idoso , Idoso de 80 Anos ou mais , Esôfago de Barrett/tratamento farmacológico , Esôfago de Barrett/patologia , Esofagoscopia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fotoquimioterapia , Estudos Prospectivos , Falha de Tratamento , Resultado do Tratamento
9.
Clin Transl Gastroenterol ; 12(6): e00364, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34142665

RESUMO

The prevalence of obesity, type 2 diabetes mellitus, and metabolic syndromes is increasing globally. Minimally invasive metabobariatric (MB) endoscopic therapies are adjunct treatments that can potentially bridge the gap between surgical interventions and medical therapy. A growing number of MB techniques are becoming available, allowing for more personalized and patient-targeted treatment options for specific disease states. MB techniques are less invasive than surgery and can precisely target different parts of the gastrointestinal tract that may be responsible for the pathophysiology of obesity and metabolic syndromes such as type 2 diabetes mellitus. These alternatives should be selected on an individualized patient basis to balance the expected clinical outcomes and desired anatomical targets with the level of invasiveness and degree of acceptable risk. Each MB intervention presents great flexibility allowing for a tailored intervention and different levels of patient engagement. Patient awareness and motivation are essential to avoid therapy withdrawal and failure. Differences between MB procedures in terms of weight loss and metabolic benefit will be discussed in this review, along with the insights on clinical decision-making processes to evaluate the potential of further evolution and growth of bariatric and metabolic endoscopy.


Assuntos
Cirurgia Bariátrica/métodos , Diabetes Mellitus Tipo 2/cirurgia , Endoscopia Gastrointestinal/métodos , Síndrome Metabólica/prevenção & controle , Obesidade/cirurgia , Diabetes Mellitus Tipo 2/patologia , Humanos , Obesidade/patologia , Redução de Peso
10.
Br J Cancer ; 102(11): 1608-17, 2010 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-20461081

RESUMO

BACKGROUND AND AIMS: DNA ploidy abnormalities (aneuploidy/tetraploidy) measured by flow cytometry (FC) are strong predictors of future cancer development in untreated Barrett's oesophagus, independent of histology grade. Image cytometric DNA analysis (ICDA) is an optical technique allowing visualisation of abnormal nuclei that may be undertaken on archival tissue. Our aim was to determine the accuracy of ICDA vs FC, and evaluate DNA ploidy as a prognostic biomarker after histologically successful treatment with photodynamic therapy (PDT). METHODS: Nuclei were extracted from 40 mum sections of paraffin-embedded biopsies and processed for ICDA at UCL and FC at UW using standardised protocols. Subsequently, DNA ploidy was evaluated by ICDA on a cohort of 30 patients clear of dysplasia 1 year after aminolaevulinic acid PDT for high-grade dysplasia (HGD). The results were correlated with long-term outcome. RESULTS: In the comparative study, 93% (41 out of 44) of cases were classified identically. Errors occurred in the near-diploid region by ICDA and the tetraploid region by FC. In the cohort study, there were 13 cases of late relapse (7 cancer, 6 HGD) and 17 patients who remained free of dysplasia after a mean follow-up of 44 months. Aneuploidy post-PDT was highly predictive for recurrent HGD or cancer with a hazard ratio of 8.2 (1.8-37.8) (log-rank P=0.001). CONCLUSIONS: ICDA is accurate for the detection of DNA ploidy abnormalities when compared with FC. After histologically successful PDT, patients with residual aneuploidy are significantly more likely to develop HGD or cancer than those who become diploid. DNA ploidy by ICDA is a valuable prognostic biomarker after ablative therapy.


Assuntos
Adenocarcinoma/diagnóstico , Esôfago de Barrett/diagnóstico , Esôfago de Barrett/tratamento farmacológico , Aberrações Cromossômicas , Esôfago/patologia , Citometria por Imagem , Fotoquimioterapia , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Idoso , Esôfago de Barrett/genética , Esôfago de Barrett/patologia , Estudos de Casos e Controles , Análise Citogenética/métodos , DNA de Neoplasias/genética , Esôfago/metabolismo , Feminino , Citometria de Fluxo/métodos , Humanos , Hiperplasia/diagnóstico , Hiperplasia/tratamento farmacológico , Hiperplasia/genética , Citometria por Imagem/métodos , Citometria por Imagem/normas , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fotoquimioterapia/métodos , Ploidias , Prognóstico , Recidiva , Fatores de Tempo
11.
United European Gastroenterol J ; 7(2): 297-306, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-31080614

RESUMO

Background: Intrapapillary capillary loops (IPCLs) represent an endoscopically visible feature of early squamous cell neoplasia (ESCN) which correlate with invasion depth - an important factor in the success of curative endoscopic therapy. IPCLs visualised on magnification endoscopy with Narrow Band Imaging (ME-NBI) can be used to train convolutional neural networks (CNNs) to detect the presence and classify staging of ESCN lesions. Methods: A total of 7046 sequential high-definition ME-NBI images from 17 patients (10 ESCN, 7 normal) were used to train a CNN. IPCL patterns were classified by three expert endoscopists according to the Japanese Endoscopic Society classification. Normal IPCLs were defined as type A, abnormal as B1-3. Matched histology was obtained for all imaged areas. Results: This CNN differentiates abnormal from normal IPCL patterns with 93.7% accuracy (86.2% to 98.3%) and sensitivity and specificity for classifying abnormal IPCL patterns of 89.3% (78.1% to 100%) and 98% (92% to 99.7%), respectively. Our CNN operates in real time with diagnostic prediction times between 26.17 ms and 37.48 ms. Conclusion: Our novel and proof-of-concept application of computer-aided endoscopic diagnosis shows that a CNN can accurately classify IPCL patterns as normal or abnormal. This system could be used as an in vivo, real-time clinical decision support tool for endoscopists assessing and directing local therapy of ESCN.


Assuntos
Inteligência Artificial , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Carcinoma de Células Escamosas do Esôfago/patologia , Esofagoscopia , Neovascularização Patológica , Detecção Precoce de Câncer , Esofagoscopia/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Taiwan
12.
Artigo em Inglês | MEDLINE | ID: mdl-29542847

RESUMO

BACKGROUND: Esophageal dysmotility may predispose to Barrett's esophagus (BE). We hypothesized that high-resolution manometry (HRM) performed with additional physiologic challenge would better delineate dysmotility in BE. METHODS: Included patients had typical reflux symptoms and underwent endoscopy, HRM with single water swallows and adjunctive testing with solids and rapid drink challenge (RDC) before ambulatory pH-impedance monitoring. BE and endoscopy-negative reflux disease (ENRD) subjects were compared against functional heartburn patient-controls (FHC). Primary outcome was incidence of HRM contractile abnormalities with standard and adjunctive swallows. Secondary outcomes included clearance measures and symptom association on pH-impedance. KEY RESULTS: Seventy-eight patients (BE 25, ENRD 27, FHC 26) were included. Water swallow contractility was reduced in both BE (median DCI 87 mm Hg/cm/s) and ENRD (442 mm Hg/cm/s) compared to FHC (602 mm Hg/cm/s; P < .001 and .04, respectively). With the challenge of solid swallows and RDC, these parameters improved in ENRD (solids = 1732 mm Hg/cm/s), becoming similar to FHC (1242 mm Hg/cm/s; P = .93), whereas abnormalities persisted in BE (818 mm Hg/cm/s; P < .01 c.f. FHC). In BE and ENRD, reflux events (67 vs 57 events/24 hour) and symptom frequency were similar; yet symptom correlation was significantly better in ENRD compared to BE, which was comparable to FHC (symptom index 30% vs 4% vs 0%, respectively). Furthermore, bolus clearance and exposure times were more pronounced in BE (P < .01). CONCLUSIONS & INFERENCES: Reduced contractile effectiveness persisted in BE with the more representative esophageal challenge of swallowing solids and free drinking; while in ENRD and FHC peristalsis usually improved, demonstrating peristaltic reserve. Furthermore, symptom association and refluxate clearance were reduced in BE. These factors may underlie BE pathogenesis.

13.
Commun Agric Appl Biol Sci ; 71(3 Pt B): 1063-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17390860

RESUMO

The aim of this work was to find agronomic eco-compatible ("natural") control solutions against grey mould of grapevine too. Our researches about "minimum pruning", "minimal pruning" and "physiological pruning" started in 1980, and in 1983 with specific relation to grey mould on vines of Merlot, Cabernet sauvignon and Chardonnay previously set in vegetative and productive growth balance. These researches were conducted to verify the affordability of innovative winter pruning techniques like "minimum pruning", "minimal pruning" and the so called 'physiological pruning", in the natural agronomic eco-compatible grey mould control. As a result we found that the new techniques contribute to limit the incidence of grey mould; especially "physiological pruning" followed by "minimal pruning" and 'minimum pruning". The best results were observed on Chardonnay, followed by Merlot and Cabernet sauvignon.


Assuntos
Agricultura/métodos , Botrytis/patogenicidade , Doenças das Plantas/microbiologia , Vitis/crescimento & desenvolvimento , Vitis/microbiologia , Vinho
15.
Gastrointest Endosc Clin N Am ; 10(3): 533-50, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10899262

RESUMO

This article reviews current knowledge on the biology of photodynamic therapy on normal and diseased tissues in the gastrointestinal tract. There is little effect on connective tissue, so the mechanical integrity of the luminal gut is well preserved, even with full thickness damage. This makes photodynamic therapy suitable for treating small tumors, but strictures may occur after circumferential treatment of conditions like Barrett's esophagus unless a muscle-sparing photosensitizing agent is used. Animal studies show that the pancreas and surrounding tissues can tolerate photodynamic therapy, justifying pilot clinical trials on percutaneous, interstitial photodynamic therapy for localized, inoperable pancreatic cancers.


Assuntos
Sistema Digestório/metabolismo , Gastroenteropatias/metabolismo , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacocinética , Animais , Sistema Digestório/patologia , Sistema Digestório/efeitos da radiação , Gastroenteropatias/tratamento farmacológico , Gastroenteropatias/patologia , Humanos , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos da radiação , Luz , Fármacos Fotossensibilizantes/uso terapêutico
19.
Gut ; 55(8): 1078-83, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16469795

RESUMO

BACKGROUND AND AIMS: Endoscopic surveillance of Barrett's oesophagus currently relies on multiple random biopsies. This approach is time consuming, has a poor diagnostic yield, and significant interobserver variability. Elastic scattering spectroscopy is a real time in vivo optical technique which detects changes in the physical properties of cells. The aim of this study was to assess the potential for elastic scattering to detect high grade dysplasia or cancer within Barrett's oesophagus. METHODS: Elastic scattering spectroscopy measurements collected in vivo were matched with histological specimens taken from identical sites within Barrett's oesophagus. All biopsies were reviewed by three gastrointestinal pathologists and defined as either "low risk" (non-dysplastic or low grade dysplasia) or "high risk" (high grade dysplasia or cancer). Two different statistical approaches (leave one out and block validation) were used to validate the model. RESULTS: A total of 181 matched biopsy sites from 81 patients, where histopathological consensus was reached, were analysed. There was good pathologist agreement in differentiating high grade dysplasia and cancer from other pathology (kappa = 0.72). Elastic scattering spectroscopy detected high risk sites with 92% sensitivity and 60% specificity and differentiated high risk sites from inflammation with a sensitivity and specificity of 79%. If used to target biopsies during endoscopy, the number of low risk biopsies taken would decrease by 60% with minimal loss of accuracy. A negative spectroscopy result would exclude high grade dysplasia or cancer with an accuracy of >99.5%. CONCLUSIONS: These preliminary results show that elastic scattering spectroscopy has the potential to target conventional biopsies in Barrett's surveillance saving significant endoscopist and pathologist time with consequent financial savings. This technique now requires validation in prospective studies.


Assuntos
Adenocarcinoma/diagnóstico , Esôfago de Barrett/diagnóstico , Neoplasias Esofágicas/diagnóstico , Lesões Pré-Cancerosas/diagnóstico , Adenocarcinoma/patologia , Algoritmos , Esôfago de Barrett/patologia , Biópsia , Diagnóstico Diferencial , Elasticidade , Neoplasias Esofágicas/patologia , Esofagite/diagnóstico , Esofagite/patologia , Esofagoscopia , Humanos , Vigilância da População , Lesões Pré-Cancerosas/patologia , Sensibilidade e Especificidade , Análise Espectral/métodos
20.
Gut ; 38(3): 306-9, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8675079

RESUMO

Few gastrointestinal functions decline to an important extent as a result of old age alone and there is little clinical evidence that significant malnutrition occurs in any normal elderly person as a result of the aging process itself. Nevertheless, decreased gastrointestinal reserve makes older people highly sensitive to minor insults and decompensation can rapidly occur. Drugs appreciably affect taste sensation, which is already blunted and psychological as well as physical disability can have a major impact on appetite. Malabsorption can be caused by gastric hypochlorhydria with small bowel bacterial overgrowth and while gastrointestinal dysmotility can be caused by subclinical hypothyroidism, it can improve in response to physical exercise. Evidence is now mounting that thorough investigation of gastrointestinal disturbances in elderly patients coupled with intensive nutritional support can make a very real impact on their outcome. Gastroenterologists should therefore seek out and actively treat gastrointestinal disorders in the elderly and not just ascribe them to old age.


Assuntos
Envelhecimento/fisiologia , Intestinos/fisiologia , Estado Nutricional , Idoso , Humanos , Síndromes de Malabsorção/fisiopatologia , Distúrbios Nutricionais/fisiopatologia , Distúrbios Nutricionais/terapia
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