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1.
Endosc Int Open ; 10(1): E9-E18, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35047330

RESUMEN

Background and study aims Fujifilm has developed a novel ELUXEO 7000 endoscope system that employs light-emitting diodes (LEDs) at four different wavelengths as light sources that enable blue light imaging (BLI), linked color imaging (LCI), and high-definition white-light endoscopy (HD-WLE). The aim of this study was to address the diagnostic accuracy of real-time polyp characterization using BLI, LCI and HD-WLE (ELUXEO 7000 endoscopy system). Patients methods This is a prespecified post-hoc analysis of a prospective study in which 22 experienced endoscopists (> 2,000 colonoscopies) from eight international centers participated. Using a combination of BLI, LCI, and HD-WLE, lesions were endoscopically characterized including a high- or low-confidence statement. Per protocol, digital images were created from all three imaging modalities. Histopathology was the reference standard. Endoscopists were familiar with polyp characterization, but did not take dedicated training for purposes of this study. Results Overall, 341 lesions were detected in 332 patients. Of the lesions, 269 histologically confirmed polyps with an optical diagnosis were included for analysis (165 adenomas, 27 sessile serrated lesions, and 77 hyperplastic polyps). Overall, polyp characterization was performed with high confidence in 82.9 %. The overall accuracy for polyp characterization was 75.1 % (95 % confidence interval [CI] 69.5-80.1 %), compared with an accuracy of 78.0 % (95 % CI 72.0-83.2 %) for high confidence assignments. The accuracy for endoscopic characterization for diminutive polyps was 74.7 % (95 %CI 68.4-80.3 %), compared with an accuracy of 78.2 % (95 % CI 71.4-84.0 %) for high-confidence assignments. Conclusions The diagnostic accuracy of BLI, LCI, and HD-WLE by experienced endoscopist for real-time polyp characterization seems limited (NCT03344289).

2.
J Occup Rehabil ; 31(2): 323-338, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32880094

RESUMEN

Purpose The aim of this research was to study the effectiveness on return to work (RTW) of an early tailored work-related support intervention in patients diagnosed with curative gastrointestinal cancer. Methods A multicenter randomized controlled trial was undertaken, in which patients were assigned randomly to the intervention or the control group (usual care). The intervention encompassed three psychosocial work-related support meetings, starting before treatment. Five self-reported questionnaires were sent over twelve months of follow-up. Primary outcome was days until RTW (fulltime or partial) and secondary outcomes included work status, quality of life, work ability, and work limitations. Descriptive analysis, Kaplan-Meier analysis, relative risk ratio and linear mixed models were applied. Results Participants (N = 88) had a mean age of 55 years; 67% were male and the most common cancer type was colon cancer (66%). Of the participants, 42 were randomized to the intervention group. The median time from sick leave until RTW was 233 days (range 187-279 days) for the control group, versus 190 days (range 139-240 days) for the intervention group (log-rank p = 0.37). The RTW rate at twelve months after baseline was 83.3% for the intervention group and 73.5% for the control group. Work limitations did statistically differ between the groups over time (p = 0.01), but quality of life and work ability did not. Conclusion Patients in the intervention group seem to take fewer days to RTW, albeit not to a statistically significant extent.Trial registration Trial NL4920 (NTR5022) (Dutch Trial Register https://www.trialregister.nl ).


Asunto(s)
Neoplasias Gastrointestinales , Calidad de Vida , Empleo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reinserción al Trabajo , Ausencia por Enfermedad
3.
Int J Qual Health Care ; 29(7): 966-971, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29177408

RESUMEN

QUALITY PROBLEM: Patients with gastrointestinal malignancies often need multiple appointments with different medical specialists, causing waiting times to accrue. INITIAL ASSESSMENT: In our hospital, care is organized in a sequential manner, causing long waiting times. To reduce this, a fast track outpatient clinic (FTC) was implemented. CHOICE OF SOLUTION: The FTC was organized within the hospital's existing structure. Patient centered care was achieved by ensuring that the medical specialists visit the patient, implementing nurse coordinators and considering patient wishes and co-morbidities when formulating a treatment plan. IMPLEMENTATION: A mandate from the board (Top-down), ensured cooperation between different medical departments and a change in resource allocation (i.e. medical staff); a horizontal clinic across a vertical departmental structure. Brainstorm sessions between the departments led by two physicians who were going to work at the FTC (Bottom-up), assured a swift implementation of the FTC. EVALUATION: Since implementation in 2009, patient influx has tripled. Waiting time for an appointment and start of treatment was reduced from 2-4 weeks to 6 working days and from 12-14 weeks to 17 working days, respectively. This was achieved by re-allocating recourses, but without increasing existing resources. LESSONS LEARNED: The combination of a top-down and bottom-up strategy ensured participation from all involved departments, a strong foundation and a shared vision on patient centered care. The FTC facilitates sharing information between different medical specialists through both proximity and a shared electronic patient record. The implementation of the FTC comprises a change in organization, but not a change in structure.


Asunto(s)
Neoplasias Gastrointestinales/diagnóstico , Neoplasias Gastrointestinales/terapia , Servicio Ambulatorio en Hospital/organización & administración , Mejoramiento de la Calidad/organización & administración , Citas y Horarios , Comorbilidad , Hospitales Universitarios , Humanos , Servicio Ambulatorio en Hospital/normas , Atención Dirigida al Paciente/organización & administración , Factores de Tiempo
4.
Gynecol Oncol ; 147(3): 684-689, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29074259

RESUMEN

OBJECTIVE: To evaluate the frequency of and risk factors for severe late bowel toxicity after curative radiotherapy in women treated for locally advanced cervical cancer. METHODS: Included were 515 women treated for locally advanced cervical cancer with primary radiotherapy with curative intent from 1992 to 2013. Bowel toxicity was graded according to the Common Terminology Criteria for Adverse Events. Associations between risk factors and severe late bowel toxicity were assessed using Cox proportional hazards regression models. RESULTS: Median follow-up was 78months. Fifty-nine patients developed severe late bowel toxicity. The actuarial 3-year and 5-year severe late bowel toxicity rates were both 13%. In the multivariable analysis, factors significantly associated with severe late bowel toxicity were: smoking (HR 2.59 [1.48-4.55]), severe acute bowel toxicity (HR 2.46 [1.24-4.49]), previous major abdominal surgery (HR 2.35 [1.20-4.60]), hypertension (HR 2.33 [1.23-4.40]), parametrial boost (HR 2.18 [1.10-4.33]), low socioeconomic status (HR 2.05 [1.17-3.59]) and low BMI (HR 0.93 [0.88-0.99]). First symptoms of severe late bowel toxicity were reported after a median follow-up of 9months, but occurred up to 10years after end of treatment. Only one third of the patients with severe late bowel toxicity were referred to a gastroenterologist. CONCLUSIONS: Severe late bowel toxicity is a frequent complication of definitive radiotherapy for cervical cancer. Several independent risk factors were found which warrant further research. A standardized and structured approach in the early diagnostics and management of bowel toxicity is needed.


Asunto(s)
Traumatismos por Radiación/economía , Traumatismos por Radiación/etiología , Neoplasias del Cuello Uterino/economía , Neoplasias del Cuello Uterino/radioterapia , Adulto , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Riesgo , Clase Social , Adulto Joven
5.
Int J Health Care Qual Assur ; 29(5): 523-35, 2016 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-27256775

RESUMEN

Purpose - Guidelines stating maximum waiting times fail to take cancer patients' expectations into account. Therefore, the purpose of this paper is to assess patients' expectations and experiences with their waiting time at a fast-track clinic. Design/methodology/approach - Patients were selected using a purposeful sampling strategy and were interviewed four times: before the visit; one day after; two weeks after the visit; and one week after starting treatment. Interviews were audiotaped and independently coded by two researchers. Findings - All patients (n=9) preferred a short waiting time before the first visit; they feared that their disease would spread and believed that cancer warrants priority treatment. Six patients experienced the waiting time as short, one had no expectations and two felt they waited longer than expected; three patients changed this evaluation during the study. Six patients received treatment - four preferred to wait before treatment and two wanted to start treatment immediately. Reasons to wait included putting one's affairs in order, or needing to adjust to the diagnosis. Practical implications - Cancer patients prefer a short waiting time before the first visit but have different expectations and needs regarding waiting time before treatment. Ideally, their expectations are managed by their treating physician to match waiting time reality. Originality/value - This is the first study to assess cancer patients' waiting time experiences and how these experiences change over time. This study paves the way for establishing a framework to better assess patient satisfaction with oncology care waiting time. An important aspect, is managing patients' expectations.


Asunto(s)
Instituciones de Atención Ambulatoria/organización & administración , Citas y Horarios , Neoplasias Gastrointestinales/diagnóstico , Neoplasias Gastrointestinales/terapia , Satisfacción del Paciente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Neoplasias Gastrointestinales/psicología , Humanos , Entrevistas como Asunto , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Listas de Espera
7.
BMC Surg ; 15: 78, 2015 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-26123286

RESUMEN

BACKGROUND: At least a third of patients with a colorectal carcinoma who are candidate for surgery, are anaemic preoperatively. Preoperative anaemia is associated with increased morbidity and mortality. In general practice, little attention is paid to these anaemic patients. Some will have oral iron prescribed others not. The waiting period prior to elective colorectal surgery could be used to optimize a patients' physiological status. The aim of this study is to determine the efficacy of preoperative intravenous iron supplementation in comparison with the standard preoperative oral supplementation in anaemic patients with colorectal cancer. METHODS/DESIGN: In this multicentre randomized controlled trial, patients with an M0-staged colorectal carcinoma who are scheduled for curative resection and with a proven iron deficiency anaemia are eligible for inclusion. Main exclusion criteria are palliative surgery, metastatic disease, neoadjuvant chemoradiotherapy (5 × 5 Gy = no exclusion) and the use of Recombinant Human Erythropoietin within three months before inclusion or a blood transfusion within a month before inclusion. Primary endpoint is the percentage of patients that achieve normalisation of the haemoglobin level between the start of the treatment and the day of admission for surgery. This study is a superiority trial, hypothesizing a greater proportion of patients achieving the primary endpoint in favour of iron infusion compared to oral supplementation. A total of 198 patients will be randomized to either ferric(III)carboxymaltose infusion in the intervention arm or ferrofumarate in the control arm. This study will be performed in ten centres nationwide and one centre in Ireland. DISCUSSION: This is the first randomized controlled trial to determine the efficacy of preoperative iron supplementation in exclusively anaemic patients with a colorectal carcinoma. Our trial hypotheses a more profound haemoglobin increase with intravenous iron which may contribute to a superior optimisation of the patient's condition and possibly a decrease in postoperative morbidity. TRIAL REGISTRATION: ClincalTrials.gov: NCT02243735 .


Asunto(s)
Anemia Ferropénica/tratamiento farmacológico , Neoplasias Colorrectales/cirugía , Compuestos Férricos/administración & dosificación , Compuestos Ferrosos/administración & dosificación , Fumaratos/administración & dosificación , Hematínicos/administración & dosificación , Maltosa/análogos & derivados , Cuidados Preoperatorios/métodos , Administración Oral , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anemia Ferropénica/etiología , Protocolos Clínicos , Neoplasias Colorrectales/complicaciones , Suplementos Dietéticos , Femenino , Compuestos Férricos/uso terapéutico , Compuestos Ferrosos/uso terapéutico , Fumaratos/uso terapéutico , Hematínicos/uso terapéutico , Humanos , Infusiones Intravenosas , Masculino , Maltosa/administración & dosificación , Maltosa/uso terapéutico , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
8.
Colorectal Dis ; 14(4): 469-73, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21689341

RESUMEN

AIM: A recent systematic review indicated that dysplasia present before restorative proctocolectomy is a predictor of subsequent dysplasia in the pouch. This prospective study was carried out to assess the prevalence of dysplasia in the ileal pouch in patients having RPC for ulcerative colitis with co-existing dysplasia in the operation specimen. METHOD: Eligible patients were invited for a surveillance endoscopy. The afferent and blind efferent ileal loop, ileoanal pouch and rectal cuff were examined by standard endoscopy using a dye-spray technique with methylene blue. Mucosal abnormalities were biopsied and random biopsies were taken from the afferent and blind ileal loop, pouch and rectal cuff. RESULTS: Fourty-four patients (25 male, mean 49 years) underwent pouch endoscopy at a mean interval from RPC of 8.6 years. Dysplasia was detected in two (4.5%) patients. In one, low-grade dysplasia was found in the rectal cuff and in the other low-grade dysplasia was detected in random biopsies from the pouch and the efferent ileal loop. CONCLUSION: This prospective pouch-endoscopy study detected dysplasia in < 5% of patients over nearly 10 years. The benefit of routine surveillance for dysplasia in the pouch is uncertain, as the significance of low-grade dysplasia in the pouch is not clear.


Asunto(s)
Colitis Ulcerosa/cirugía , Reservorios Cólicos/patología , Enfermedades del Íleon/etiología , Complicaciones Posoperatorias , Proctocolectomía Restauradora , Enfermedades del Recto/etiología , Adulto , Biopsia , Colitis Ulcerosa/patología , Colonoscopía , Colorantes , Femenino , Humanos , Enfermedades del Íleon/epidemiología , Enfermedades del Íleon/patología , Masculino , Azul de Metileno , Persona de Mediana Edad , Vigilancia de la Población , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/patología , Prevalencia , Estudios Prospectivos , Enfermedades del Recto/epidemiología , Enfermedades del Recto/patología
9.
BMJ Open ; 1(2): e000190, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22138895

RESUMEN

Objective To assess the employment status of patients with gastrointestinal cancer at diagnosis and to examine work-related problems of employed patients. Design New, consecutive patients were included at the Gastrointestinal Oncology Center Amsterdam, a one-stop, rapid access diagnostic assessment centre. Patients were interviewed on their employment status by a nurse. If (self-) employed, patients were asked to self-report on work-related problems, perceived distress (0-10), cancer-related problems, fatigue (MFI-20, range 4-20) and work ability (three WAI questions, range 0-10). Results Of all 333 included new consecutive patients (age range 32-89 years), 95 patients (28%) were (self-) employed at time of diagnosis, 179 (54%) were pensioners, and 59 were not working (18%). For the assessment of work-related problems, 45 (47%) of these 95 employed patients with cancer participated. Their mean age was 56 years, and patients had oesophageal/stomach (49%), colorectal (18%) or hepatic/pancreatic/biliary cancer (33%). Half of the employed patients (49%) were still at work, while 51% were on sick leave. The main reasons for sick leave were stress (35%), (scheduled) operation (26%), fatigue (17%) and pain (13%). Most patients on sick leave (70%) had no contact with their own occupational physician, although the majority (67%) would like to continue to work. Work-related problems were experienced by 73% of working patients. The mean work ability was 5.4, the mean general fatigue score was 11.5, and the mean distress score was 4.7. Employed patients on sick leave reported a lower work ability, more fatigue and higher distress but no more cancer-related problems compared with those still working. Conclusion A quarter of all patients with gastrointestinal cancer seen at an oncological centre are employed at time of diagnosis, and of these employed patients, 73% experience work-related problems. During diagnosis and treatment, information and support on work-related issues should be offered to patients with cancer as an essential part of high-quality oncological care.

10.
Endoscopy ; 42(1): 42-5, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19967633
11.
Gut ; 46(5): 601-7, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10764701

RESUMEN

BACKGROUND: The bacterium Helicobacter pylori is able to adhere to and to colonise the human gastric epithelium, yet the primary gene product responsible as a receptor for its adherence has not been identified. AIMS: To investigate the expression of the gastric mucins MUC5AC and MUC6 in the gastric epithelium in relation to H pylori colonisation in order to examine their possible roles in the binding of H pylori. PATIENTS: Seventy two consecutive patients suspected of having H pylori infection. METHODS: MUC5AC, MUC6, and H pylori were detected in single sections of antral biopsy specimens using immunohistochemical triple staining. RESULTS: MUC5AC was expressed in the superficial epithelium and the upper part of the gastric pits. MUC6 expression was detected in the lower part of the gastric pits. The expression of both mucins in the epithelium was complementary. In each patient, there was a sharply delineated transition between MUC5AC and MUC6 producing cell populations. In all H pylori positive patients there was a striking colocalization of H pylori and MUC5AC; more than 99% of the bacteria were associated with either extracellular MUC5AC or the apical domain of MUC5AC producing cells. CONCLUSIONS: H pylori is very closely associated with extracellular MUC5AC and epithelial cells that produce MUC5AC. This indicates that MUC5AC, but not MUC6, plays a role in the adhesion of H pylori to the gastric mucosa.


Asunto(s)
Adhesión Bacteriana/fisiología , Infecciones por Helicobacter/metabolismo , Helicobacter pylori/fisiología , Mucinas/metabolismo , Mucosa Gástrica/metabolismo , Mucosa Gástrica/microbiología , Expresión Génica , Infecciones por Helicobacter/microbiología , Helicobacter pylori/aislamiento & purificación , Humanos , Inmunohistoquímica , Mucina 5AC , Mucina 6 , Estudios Prospectivos
12.
Am J Physiol ; 276(1): G115-24, 1999 01.
Artículo en Inglés | MEDLINE | ID: mdl-9886986

RESUMEN

To help us investigate the role of mucin in the protection of the colonic epithelium in the mouse, we aimed to identify the murine colonic mucin (MCM) and its encoding gene. We isolated MCM, raised an anti-MCM antiserum, and studied the biosynthesis of MCM in the gastrointestinal tract. Isolated MCM resembled other mucins in physicochemical properties. Anti-MCM recognized MCM as well as rat and human MUC2 on Western blots, interacting primarily with peptide epitopes, indicating that MCM was identical to murine Muc2. Using anti-MCM and previously characterized anti-human and anti-rat MUC2 antibodies, we identified a murine Muc2 precursor in the colon of approximately 600 kDa, which appeared similar in size to rat and human MUC2 precursors. Western blotting, immunoprecipitation of metabolically labeled mucins, and immunohistochemistry showed that murine Muc2 was expressed in the colon and the small intestine but was absent in the stomach. To independently identify murine Muc2, we cloned a cDNA fragment from murine colonic mRNA, encoding the 302 NH2-terminal amino acids of murine Muc2. The NH2 terminus of murine Muc2 showed 86 and 75% identity to the corresponding rat and human MUC2 peptide sequences, respectively. Northern blotting with a murine Muc2 cDNA probe showed hybridization to a very large mRNA, which was expressed highly in the colon and to some extend in the small intestine but was absent in the stomach. In situ hybridization showed that the murine Muc2 mRNA was confined to intestinal goblet cells. In conclusion, by two independent sets of experiments we identified murine Muc2, which appears homologous to rat and human MUC2. Because Muc2 is prominently expressed in the colon, it is most likely to be the predominant mucin in the colonic mucus layer.


Asunto(s)
Clonación Molecular , ADN Complementario/genética , Sistema Digestivo/metabolismo , Mucinas/genética , Mucinas/metabolismo , Secuencia de Aminoácidos , Animales , Colon/metabolismo , ADN Complementario/aislamiento & purificación , Femenino , Células Caliciformes/metabolismo , Humanos , Mucosa Intestinal/citología , Mucosa Intestinal/metabolismo , Masculino , Ratones , Datos de Secuencia Molecular , Mucina 2 , Mucinas/aislamiento & purificación , ARN Mensajero/metabolismo , Ratas
13.
Neth J Med ; 51(3): 119-22, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9360413

RESUMEN

Abdominal tuberculosis is often diagnosed in a late stage because symptoms are aspecific. Two patients with intestinal tuberculosis and tuberculous peritonitis respectively, both from endemic countries presented with long-standing fever, abdominal pain and weight loss. Acid fast bacilli were present in aspirate and biopsy specimens obtained by colonoscopy and laparoscopy respectively; PCR was positive for M. tuberculosis complex and later M. tuberculosis was cultured. Both patients responded to antituberculous therapy. In one patient AIDS was diagnosed.


Asunto(s)
Enfermedades del Colon/diagnóstico , Enfermedades Peritoneales/diagnóstico , Tuberculosis Gastrointestinal/diagnóstico , Adulto , Antituberculosos/uso terapéutico , Colon/microbiología , Enfermedades del Colon/tratamiento farmacológico , Enfermedades del Colon/microbiología , Colonoscopía , ADN Bacteriano/análisis , Diagnóstico Diferencial , Femenino , Humanos , Laparoscopía , Masculino , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/aislamiento & purificación , Enfermedades Peritoneales/tratamiento farmacológico , Enfermedades Peritoneales/microbiología , Peritoneo/microbiología , Reacción en Cadena de la Polimerasa , Tuberculosis Gastrointestinal/tratamiento farmacológico , Tuberculosis Gastrointestinal/microbiología
14.
Biochem Biophys Res Commun ; 224(2): 397-405, 1996 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-8702401

RESUMEN

MUC2 is the predominant mucin in the human colon responsible for the protective mucus layer. We developed methods to quantify MUC2 biosynthesis, which were used to study the regulation of MUC2 expression in the colon of normal individuals and of patients with ulcerative colitis. Colonic biopsies were metabolically labeled, and biosynthesis of MUC2 precursor was quantified using SDS-PAGE. Total MUC2 and MUC2 mRNA were quantified using blotting techniques. MUC2 precursor biosynthesis and total MUC2 levels were significantly decreased in ulcerative colitis patients with active inflammation compared to controls. In contrast, both these parameters returned to control values during remission of the inflammation, demonstrating that colonic biosynthesis and total amounts of MUC2 vary according to the activity of the disease. However, MUC2 mRNA levels were similar in all patients and independent of disease activity, indicating that these variations in MUC2 synthesis are post-transcriptionally regulated.


Asunto(s)
Biomarcadores de Tumor/análisis , Colitis Ulcerosa/metabolismo , Colon/metabolismo , Mucosa Intestinal/metabolismo , Mucinas/biosíntesis , Biopsia , Colitis Ulcerosa/patología , Colon/citología , Colon/patología , Colon Sigmoide/citología , Colon Sigmoide/metabolismo , Colon Sigmoide/patología , Humanos , Mucosa Intestinal/citología , Mucosa Intestinal/patología , Mucina 2 , Mucinas/análisis , ARN Mensajero/análisis , Valores de Referencia , Análisis de Regresión , Remisión Espontánea , Transcripción Genética
15.
Gut ; 38(4): 554-63, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8707087

RESUMEN

BACKGROUND: It has been shown that MUC2 is the prominent mucin synthesised in healthy colon. AIM: To identify the predominant mucins in ulcerative colitis (UC) and to study their biosynthesis. METHODS AND RESULTS: Mucin was purified from UC resection specimens. This mucin on sodium dodecylsulphate polyacrylamide gel electrophoresis (SDS-PAGE) presented as one, high molecular weight, periodic acid/Schiff's reagent (PAS) stainable band. Amino acid composition showed a close resemblance to that of MUC2. Immunoprecipitation with a specific anti-MUC2 antiserum confirmed that this mucin was MUC2. In addition, on the mRNA level MUC2 was also the most prominent mucin expressed in UC. Polyclonal antiserum was elicited, mainly recognising mucin peptide epitopes of UC and normal colonic mucin. Biosynthetic studies with [35S]amino acids showed that the MUC2-precursor in UC displayed a molecular mass on SDS-PAGE of approximately 600 kDa. This precursor was converted into a mature MUC2 with anomalous mobility on SDS-PAGE of 550 kDa and was secreted. Only this 550 kDa band could be labelled with [35S]sulphate and stained by PAS. CONCLUSIONS: This study shows that in parallel with the mucin expression in healthy controls, MUC2 is the major mucin expressed in UC. Qualitatively, MUC2 biosynthesis seems unchanged in UC.


Asunto(s)
Colitis Ulcerosa/metabolismo , Colon/metabolismo , Mucinas/análisis , Mucinas/biosíntesis , Aminoácidos/metabolismo , Secuencia de Bases , Biomarcadores , Northern Blotting , Colon/química , Sondas de ADN , Electroforesis en Gel de Poliacrilamida , Humanos , Inmunohistoquímica , Datos de Secuencia Molecular , Mucina 2 , ARN Mensajero/metabolismo
19.
Biochem J ; 309 ( Pt 1): 221-9, 1995 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-7619060

RESUMEN

In order to identify the mucins synthesized and secreted in the rat colon, we studied their biochemical characteristics and biosynthesis and evaluated their analogy to human colonic mucins. Purified mucin from both species appeared similar with respect to composition, buoyant density and mobility on SDS/PAGE. Isolated rat colonic mucin (RCM) was used to elicit a polyclonal antiserum, which was used in metabolic labelling studies to identify mucins and mucin precursors. RCM is synthesized as a 600 kDa precursor protein, which oligomerizes before O-glycosylation. The mature, high-molecular mass mucin is secreted and displays an anomalous molecular mass on SDS/PAGE of approximately 650 kDa. Polymorphism in precursor size was found among different rats, suggesting genetic heterogeneity. Molecular mass, biosynthesis and secretion of RCM appeared similar to human MUC2. Moreover, RCM precursor could be immunoprecipitated using specific anti-(human MUC2) antisera, indicating that the RCM can be designated rat MUC2. This study describes the biosynthesis of two homologous mucins in two different species. The high degree of similarity suggests functional analogy.


Asunto(s)
Colon/metabolismo , Mucinas/biosíntesis , Aminoácidos/análisis , Animales , Humanos , Mucina 2 , Mucinas/química , Ratas , Ratas Wistar
20.
Anal Biochem ; 226(2): 331-41, 1995 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-7540809

RESUMEN

Mucins are very heavily O-glycosylated glycoproteins. For in depth studies on the cell biological aspects of mucins, anti-polypeptide antibodies are essential. We therefore developed a method for the preparation and screening of polyclonal antisera against mucin peptide epitopes. Mucins from five different tissues were isolated using CsCl/guanidinium.HCl density gradient centrifugation, and polyclonal antisera were prepared. Specificity for mucin peptide epitopes was determined by Western blotting, immunohistochemistry, and immunoprecipitation. The versatility of each anti-mucin antiserum for the study of mucin biosynthesis was tested in metabolic labeling experiments on tissue explants. All polyclonal antisera were directed primarily against peptide epitopes of mucin precursors as well as of fully glycosylated mucins. Each of the polyclonal antisera enabled us to study the mucin biosynthesis in the organ where the mucin was isolated from originally. Our mucin isolation method yields very pure mucins with sufficiently intact polypeptides to reproducibly elicit polyclonal anti-polypeptide antisera. As the sera recognized the polypeptides, primarily independent of the state of O-glycosylation, the intermediate steps in the biosynthesis of the mucins could be identified.


Asunto(s)
Sueros Inmunes/inmunología , Mucinas/biosíntesis , Mucinas/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Especificidad de Anticuerpos , Reacciones Antígeno-Anticuerpo/inmunología , Colon/química , Epítopos/inmunología , Humanos , Peso Molecular , Mucinas/química , Mucinas/aislamiento & purificación , Péptidos/inmunología , Pruebas de Precipitina , Ratas
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