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1.
Br J Surg ; 108(9): 1090-1096, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-33975337

RESUMO

BACKGROUND: Data on the long-term symptom burden in patients surviving oesophageal cancer surgery are scarce. The aim of this study was to identify the most prevalent symptoms and their interactions with health-related quality of life. METHODS: This was a cross-sectional cohort study of patients who underwent oesophageal cancer surgery in 20 European centres between 2010 and 2016. Patients had to be disease-free for at least 1 year. They were asked to complete a 28-symptom questionnaire at a single time point, at least 1 year after surgery. Principal component analysis was used to assess for clustering and association of symptoms. Risk factors associated with the development of severe symptoms were identified by multivariable logistic regression models. RESULTS: Of 1081 invited patients, 876 (81.0 per cent) responded. Symptoms in the preceding 6 months associated with previous surgery were experienced by 586 patients (66.9 per cent). The most common severe symptoms included reduced energy or activity tolerance (30.7 per cent), feeling of early fullness after eating (30.0 per cent), tiredness (28.7 per cent), and heartburn/acid or bile regurgitation (19.6 per cent). Clustering analysis showed that symptoms clustered into six domains: lethargy, musculoskeletal pain, dumping, lower gastrointestinal symptoms, regurgitation/reflux, and swallowing/conduit problems; the latter two were the most closely associated. Surgical approach, neoadjuvant therapy, patient age, and sex were factors associated with severe symptoms. CONCLUSION: A long-term symptom burden is common after oesophageal cancer surgery.


Assuntos
Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Medidas de Resultados Relatados pelo Paciente , Complicações Pós-Operatórias/epidemiologia , Idoso , Estudos Transversais , Europa (Continente)/epidemiologia , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Qualidade de Vida , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
2.
Dis Esophagus ; 34(7)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-32944747

RESUMO

Esophagectomy causes postprandial symptoms associated with an exaggerated postprandial gut hormone response. This study aimed to compare the gastrointestinal transit time of patients 1 year after esophagectomy with unoperated controls, including its relation to satiety gut hormone release. In this cross-sectional study, consecutive, disease-free patients after esophagectomy with pyloroplasty were compared with unoperated control subjects to assess gastric emptying (GE) and cecal arrival time (CAT). Serial plasma samples were collected before, and for 300 minutes after, a mixed-meal challenge. Body composition was assessed, and symptom scores were calculated. Eleven patients 1 year post-esophagectomy (age: 62.6 ± 9.8, male: 82%) did not show a significantly different GE pattern compared with 10 control subjects (P = 0.245). Rather, patients could be categorized bimodally as exhibiting either rapid or slow GE relative to controls. Those with rapid GE trended toward a higher postprandial symptom burden (P = 0.084) without higher postprandial glucagon-like peptide-1 (GLP-1) secretion (P = 0.931). CAT was significantly shorter after esophagectomy (P = 0.043) but was not significantly associated with GE, GLP-1 secretion, or symptom burden. Neither early nutrient delivery to the proximal small intestine nor to the colon explains the exaggerated postprandial GLP-1 response after esophagectomy. GE varies significantly in these patients despite consistent pyloric management.


Assuntos
Esofagectomia , Esvaziamento Gástrico , Estudos Transversais , Peptídeo 1 Semelhante ao Glucagon , Humanos , Masculino , Período Pós-Prandial
3.
Br J Surg ; 106(10): 1341-1351, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31282584

RESUMO

BACKGROUND: It remains controversial whether neoadjuvant chemoradiation (nCRT) for oesophageal cancer influences operative morbidity, in particular pulmonary, and quality of life. This study combined clinical outcome data with systematic evaluation of pulmonary physiology to determine the impact of nCRT on pulmonary physiology and clinical outcomes in locally advanced oesophageal cancer. METHODS: Consecutive patients treated between 2010 and 2016 were included. Three-dimensional conformal radiation was standard, with a lung dose-volume histogram of V20 less than 25 per cent, and total radiation between 40 and 41·4 Gy. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and diffusion capacity for carbon monoxide (DLCO) were assessed at baseline and 1 month after nCRT. Radiation-induced lung injury (grade 2 or greater), comprehensive complications index (CCI) and pulmonary complications were monitored prospectively. Health-related quality of life was assessed among disease-free patients in survivorship. RESULTS: Some 228 patients were studied. Comparing pulmonary physiology values before with those after nCRT, FEV1 decreased from mean(s.d.) 96·8(17·7) to 91·5(20·4) per cent (-3·6(10·6) per cent; P < 0·001), FVC from 104·9(15·6) to 98·1(19·8) per cent (-3·2(11·9) per cent; P = 0·005) and DLCO from 97·6(20·7) to 82·2(20·4) per cent (-14·8(14·0) per cent; P < 0·001). Five patients (2·2 per cent) developed radiation-induced lung injury precluding surgical resection. Smoking (P = 0·005) and increased age (P < 0·001) independently predicted percentage change in DLCO. Carboplatin and paclitaxel with 41·4 Gy resulted in a greater DLCO decline than cisplatin and 5-fluorouracil with 40 Gy (P = 0·001). On multivariable analysis, post-treatment DLCO predicted CCI (P = 0·006), respiratory failure (P = 0·020) and reduced physical function in survivorship (P = 0·047). CONCLUSION: These data indicate that modern nCRT alters pulmonary physiology, in particular diffusion capacity, which is linked to short- and longer-term clinical consequences, highlighting a potentially modifiable index of risk.


ANTECEDENTES: El tema de si en el cáncer de esófago la quimiorradioterapia neoadyuvante (neoadjuvant chemoradiation, nCRT) repercute sobre la morbilidad postoperatoria, especialmente sobre la morbilidad pulmonar y la calidad de vida de los pacientes que sobreviven sigue siendo controvertido. Este estudio combina datos sobre resultados clínicos con una evaluación sistemática de la fisiología pulmonar para determinar el impacto de la nCRT sobre la fisiología pulmonar y los resultados clínicos en el cáncer de esófago localmente avanzado. MÉTODOS: Se incluyeron pacientes consecutivos tratados entre 2010-2016. La radioterapia conformal 3D fue la estándar, con un histograma dosis-volumen del pulmón V20 < 25% y radiación entre 40-41,4 Gy. Se evaluaron el volumen espiratorio forzado (forced expiratory volume, FEV1), la capacidad vital forzada (forced vital capacity, FVC) y la capacidad de difusión del monóxido de carbono (diffusion capacity for carbon monoxide, DLCO) al inicio y un mes tras la nCRT. La lesión pulmonar inducida por la radioterapia (EORTC grado ≥ 2), el índice de complicaciones integral (comprehensive complications index, CCI), grado de Clavien-Dindo, y complicaciones pulmonares fueron analizadas de manera prospectiva. Se evaluó la calidad de vida relacionada con la salud entre los pacientes supervivientes libres de enfermedad (EORTC QLQ-C30, OG25, OES18). RESULTADOS: Se estudiaron un total de 228 pacientes. Al comparar los valores de la fisiología pulmonar antes y después de la nCRT respectivamente, la FEV1 disminuyó de 96,8 ± 17,7% a 91,5 ± 20,4% (-3,6 ± 10,6%, P = 0,0002), la FVC de 104,9 ± 15,6 a 98,1 ± 19,8% (-3,2 ± 11,9%, P = 0,005) y la DLCO de 97,6 ± 20,7 a 82,2 ± 20,4% (-14,8 ± 14,0%, P < 0,0001). Cinco pacientes (2,2%) desarrollaron lesión pulmonar relacionada con la radioterapia impidiendo la resección quirúrgica. Los factores predictores independientes de %ΔDLCO fueron el hábito tabáquico (P = 0,005) y la edad avanzada (P < 0,001). El tratamiento con carboplatino/paclitaxel/41,4Gy determinó un mayor descenso de la DLCO en comparación con cisplatino/5-fluorouracilo/40Gy (P = 0,001). En el análisis multivariable, la DLCO tras el tratamiento fue una variable predictora de CCI (P = 0,006), fracaso respiratorio/intubación prolongada (P = 0,020) y reducción de la función física en los supervivientes (P = 0,047). CONCLUSIÓN: Estos datos indican que la moderna nCRT altera la fisiología pulmonar, especialmente la difusión pulmonar, con consecuencias clínicas a corto y largo plazo. La DLCO podría constituir un factor de riesgo potencialmente modificable.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Quimiorradioterapia Adjuvante/métodos , Neoplasias Esofágicas/terapia , Qualidade de Vida , Transtornos Respiratórios/etiologia , Monóxido de Carbono/análise , Carboplatina/administração & dosagem , Esofagectomia/métodos , Feminino , Volume Expiratório Forçado/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Paclitaxel/administração & dosagem , Complicações Pós-Operatórias/etiologia , Cuidados Pré-Operatórios/métodos , Capacidade Vital/fisiologia
4.
Br J Surg ; 106(6): 735-746, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30883706

RESUMO

BACKGROUND: Oesophagectomy is associated with reduced appetite, weight loss and postprandial hypoglycaemia, the pathophysiological basis of which remains largely unexplored. This study aimed to investigate changes in enteroendocrine function after oesophagectomy. METHODS: In this prospective study, 12 consecutive patients undergoing oesophagectomy were studied before and 10 days, 6, 12 and 52 weeks after surgery. Serial plasma total fasting ghrelin, and glucagon-like peptide 1 (GLP-1), insulin and glucose release following a standard 400-kcal mixed-meal stimulus were determined. CT body composition and anthropometry were assessed, and symptom scores calculated using European Organisation for Research and Treatment of Cancer (EORTC) questionnaires. RESULTS: At 1 year, two of the 12 patients exhibited postprandial hypoglycaemia, with reductions in bodyweight (mean(s.e.m.) 17·1(3·2) per cent, P < 0·001), fat mass (21.5(2.5) kg versus 25.5(2.4) kg before surgery; P = 0·014), lean body mass (51.5(2.2) versus 54.0(1.8) kg respectively; P = 0·003) and insulin resistance (HOMA-IR: 0.84(0.17) versus 1.16(0.20); P = 0·022). Mean(s.e.m.) fasting ghrelin levels decreased from postoperative day 10, but had recovered by 1 year (preoperative: 621·5(71·7) pg/ml; 10 days: 415·1(59·80) pg/ml; 6 weeks: 309·0(42·0) pg/ml; 12 weeks: 415·8(52·1) pg/ml; 52 weeks: 547·4(83·2) pg/ml; P < 0·001) and did not predict weight loss (P = 0·198). Postprandial insulin increased progressively at 10 days, 6, 12 and 52 weeks (mean(s.e.m.) insulin AUC0-30 min : fold change 1·7(0·4), 2·0(0·4), 3·5(0·7) and 4·0(0·8) respectively; P = 0·001). Postprandial GLP-1 concentration increased from day 10 after surgery (P < 0·001), with a 3·3(1·8)-fold increase at 1 year (P < 0·001). Peak GLP-1 level was inversely associated with the postprandial glucose nadir (P = 0·041) and symptomatic neuroglycopenia (Sigstad score, P = 0·017, R2 = 0·45). GLP-1 AUC predicted loss of weight (P = 0·008, R2 = 0·52) and fat mass (P = 0·010, R2 = 0·64) at 1 year. CONCLUSION: Altered enteroendocrine physiology is associated with early satiety, weight loss and postprandial hypoglycaemia after oesophagectomy.


Assuntos
Esofagectomia , Hormônios Gastrointestinais/sangue , Hipoglicemia/etiologia , Complicações Pós-Operatórias/etiologia , Adulto , Idoso , Biomarcadores/sangue , Glicemia/metabolismo , Composição Corporal , Feminino , Seguimentos , Grelina/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Humanos , Hipoglicemia/sangue , Hipoglicemia/diagnóstico , Hipoglicemia/fisiopatologia , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Complicações Pós-Operatórias/sangue , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/fisiopatologia , Período Pós-Prandial , Estudos Prospectivos , Resposta de Saciedade , Redução de Peso
5.
Ir J Med Sci ; 186(1): 63-67, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27271165

RESUMO

BACKGROUND: Breast cancer in women under 40 years of age is rare and typically presents symptomatically. The optimal imaging modality for this patient group is controversial. Most women undergo ultrasonography with/without mammography. Young women typically have dense breasts, which can obscure the features of malignancy on film mammography, however, initial studies have suggested that digital mammography may have a more accurate diagnostic performance in younger women. Ultrasound generally performs well in this age group, although it is poor at detecting carcinoma in situ (DCIS). AIMS: To evaluate the comparative diagnostic performance of ultrasonography and digital mammography in the initial diagnostic evaluation of women under 40 years of age with symptomatic breast cancer. METHODS: Retrospective review of all women under the age of 40 years managed at our symptomatic breast cancer unit from January 2009 to December 2015. RESULTS: There were 120 patients that met the inclusion criteria for this study. The sensitivity of ultrasonography and digital mammography for breast cancer in this patient group was 95.8 and 87.5 %, respectively. The patients with a false negative mammographic examination were more likely to have dense breasts (p < 0.01). Five patients had a false negative ultrasonographic examination, withal of whom were diagnosed with DCIS detected by mammography. CONCLUSION: This study demonstrates the superior sensitivity of ultrasound for breast cancer in women under the age of 40 years, however, the results show that digital mammography has an important complimentary role in the comprehensive assessment of these patients, particularly in the diagnosis of DCIS.


Assuntos
Neoplasias da Mama/diagnóstico , Mamografia/métodos , Ultrassonografia Mamária/métodos , Adulto , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Carcinoma in Situ/diagnóstico por imagem , Feminino , Humanos , Estudos Retrospectivos , Sensibilidade e Especificidade
6.
Braz. j. med. biol. res ; 43(4): 359-366, Apr. 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-543581

RESUMO

The objective of this study was to investigate the phenomenon of learning generalization of a specific skill of auditory temporal processing (temporal order detection) in children with dyslexia. The frequency order discrimination task was applied to children with dyslexia and its effect after training was analyzed in the same trained task and in a different task (duration order discrimination) involving the temporal order discrimination too. During study 1, one group of subjects with dyslexia (N = 12; mean age = 10.9 ± 1.4 years) was trained and compared to a group of untrained dyslexic children (N = 28; mean age = 10.4 ± 2.1 years). In study 2, the performance of a trained dyslexic group (N = 18; mean age = 10.1 ± 2.1 years) was compared at three different times: 2 months before training, at the beginning of training, and at the end of training. Training was carried out for 2 months using a computer program responsible for training frequency ordering skill. In study 1, the trained group showed significant improvement after training only for frequency ordering task compared to the untrained group (P < 0.001). In study 2, the children showed improvement in the last interval in both frequency ordering (P < 0.001) and duration ordering (P = 0.01) tasks. These results showed differences regarding the presence of learning generalization of temporal order detection, since there was generalization of learning in only one of the studies. The presence of methodological differences between the studies, as well as the relationship between trained task and evaluated tasks, are discussed.


Assuntos
Adolescente , Criança , Feminino , Humanos , Masculino , Estimulação Acústica/métodos , Percepção Auditiva/fisiologia , Aprendizagem por Discriminação/fisiologia , Dislexia/fisiopatologia , Índice de Gravidade de Doença
7.
Braz. j. med. biol. res ; 42(7): 647-654, July 2009. ilus, tab
Artigo em Inglês | LILACS | ID: lil-517799

RESUMO

Studies have shown that dyslexic children present a deficiency in the temporal processing of auditory stimuli applied in rapid succession. However, discussion continues concerning the way this deficiency can be influenced by temporal variables of auditory processing tests. Therefore, the purpose of the present study was to analyze by auditory temporal processing tests the effect of temporal variables such as interstimulus intervals, stimulus duration and type of task on dyslexic children compared to a control group. Of the 60 children evaluated, 33 were dyslexic (mean age = 10.5 years) and 27 were normal controls (mean age = 10.8 years). Auditory processing tests assess the abilities of discrimination and ordering of stimuli in relation to their duration and frequency. Results showed a significant difference in the average accuracy of control and dyslexic groups considering each variable (interstimulus intervals: 47.9 ± 5.5 vs 37.18 ± 6.0; stimulus duration: 61.4 ± 7.6 vs 50.9 ± 9.0; type of task: 59.9 ± 7.9 vs 46.5 ± 9.0) and the dyslexic group demonstrated significantly lower performance in all situations. Moreover, there was an interactive effect between the group and the duration of stimulus variables for the frequency-pattern tests, with the dyslexic group demonstrating significantly lower results for short durations (53.4 ± 8.2 vs 48.4 ± 11.1), as opposed to no difference in performance for the control group (62.2 ± 7.1 vs 60.6 ± 7.9). These results support the hypothesis that associates dyslexia with auditory temporal processing, identifying the stimulus-duration variable as the only one that unequally influenced the performance of the two groups.


Assuntos
Criança , Feminino , Humanos , Masculino , Estimulação Acústica/métodos , Transtornos da Percepção Auditiva/etiologia , Dislexia/complicações , Transtornos da Percepção Auditiva/diagnóstico , Transtornos da Percepção Auditiva/fisiopatologia , Estudos de Casos e Controles , Dislexia/fisiopatologia , Fatores de Tempo
8.
Int J Cancer ; 77(6): 887-94, 1998 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-9714059

RESUMO

LNCaP lineage-derived human prostate cancer cell lines C4-2 and C4-2B4 acquire androgen independence and osseous metastatic potential in vivo. Using C4-2 and C4-2B4 the goals of the current investigation were 1) to establish an ideal bone xenograft model for prostate cancer cells in intact athymic or SCID/bg mice using an intraosseous route of tumor cell administration and 2) to compare prostate cancer metastasis by administering cells either through intravenous (i.v.) or intracardiac administration in athymic or SCID/bg mice. Subsequent to tumor cell administration, prostate cancer growth in the skeleton was assessed by radiographic bone density, serum prostate-specific antigen (PSA) levels, presence of hematogenous prostate cancer cells and histopathologic evaluation of tumor specimens in the lymph node and skeleton. Our results show that whereas LNCaP cells injected intracardially failed to develop metastasis, C4-2 cells injected similarly had the highest metastatic capability in SCID/bg mice. Retroperitoneal and mediastinal lymph node metastases were noted in 3/7 animals, whereas 2/7 animals developed osteoblastic spine metastases. Intracardiac injection of C4-2 in athymic hosts produced spinal metastases in 1/5 animals at 8-12 weeks post-injection; PC-3 injected intracardially also metastasized to the bone but yielded osteolytic responses. Intravenous injection of either LNCaP or C4-2 failed to establish tumor colonies. Intrailiac injection of C4-2 but not LNCaP nor C4-2B4 cells in athymic mice established rapidly growing tumors in 4/8 animals at 2-7 weeks after inoculation. Intrafemoral injection of C4-2 (9/16) and C4-2B4 (5/18) but not LNCaP (0/13) cells resulted in the development of osteoblastic bone lesions in athymic mice (mean: 6 weeks, range: 3-12 weeks). In SCID/bg mice, intrafemoral injection of LNCaP (6/8), C4-2 (8/8) and C4-2B4 (8/8) cells formed PSA-producing, osteoblastic tumors in the bone marrow space within 3-5 weeks after tumor cell inoculation. A stepwise increase of serum PSA was detected in all animals. Reverse transcription-polymerase chain reaction (RT-PCR) to detect hematogenously disseminated prostate cancer cells could not be correlated to either serum PSA level or histological evidence of tumor cells in the marrow space. We have thus established a PSA-producing and osteoblastic human prostate cancer xenograft model in mice.


Assuntos
Neoplasias Ósseas/secundário , Osteoblastos/metabolismo , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/patologia , Animais , Metástase Linfática/patologia , Masculino , Camundongos , Camundongos Nus , Camundongos SCID , Reação em Cadeia da Polimerase/métodos , Transcrição Gênica , Transplante Heterólogo , Células Tumorais Cultivadas/patologia
9.
Biol Psychiatry ; 30(7): 703-10, 1991 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1958767

RESUMO

Perceptual asymmetries as indicated by dichotic listening tasks have been associated with both subtype of depression and response to antidepressant treatment. To examine the association between this relatively new measure and more traditional measures of hypothalamic-pituitary-adrenal axis (HPA) activation in depression, we assessed perceptual asymmetry and basal plasma cortisol in a sample of depressed outpatients undergoing a double-blind, placebo-controlled medication trial. Each measure was examined for its ability to predict response to treatment. Perceptual asymmetry was significantly associated with plasma cortisol levels, and was also a significant predictor of treatment response. The association between plasma cortisol and treatment response did not reach significance. Our findings are limited by relatively small sample sizes but encourage further examination of perceptual asymmetry measures as predictors of treatment response and in relation to HPA activation in depression.


Assuntos
Assistência Ambulatorial , Antidepressivos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Transtorno Depressivo/fisiopatologia , Testes com Listas de Dissílabos , Dominância Cerebral/efeitos dos fármacos , Dominância Cerebral/fisiologia , Hidrocortisona/sangue , S-Adenosilmetionina/uso terapêutico , Percepção da Fala/efeitos dos fármacos , Percepção da Fala/fisiologia , Adulto , Transtorno Depressivo/psicologia , Dexametasona , Método Duplo-Cego , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Masculino , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/fisiopatologia , Prognóstico
10.
Infect Immun ; 57(7): 2179-86, 1989 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2543634

RESUMO

Binding and cytolysis of Chinese hamster ovary (CHO) cells by Entamoeba histolytica trophozoites is inhibitable by galactose (Gal) or N-acetyl-D-galactosamine (GalNAc). To better define the carbohydrate receptor for E. histolytica, we compared the binding and cytolytic target properties of 10 CHO glycosylation mutants. Each mutant expresses a uniquely altered array of N- and/or O-linked cell surface carbohydrates. Amebic adherence was reduced when lactosamine-containing N-linked carbohydrates were essentially absent (Lec1 mutant), almost undetectable when Gal and GalNAc residues were absent on both N- and O-linked carbohydrates (ldlD.Lec1 mutant), and enhanced for mutants with increased terminal Gal residues (Lec2 and Lec3). Parental CHO cells treated with neuraminidase to expose Gal residues behaved like Lec2 mutants. Binding of purified Gal or GalNAc lectin to parental, Lec1, ldlD.Lec1, and Lec2 mutant CHO cells corroborated the adherence results. The suitability of CHO cell mutants as targets for amebic cytolysis correlated with their glycosylation phenotype: the Lec1 mutants were less susceptible than parental CHO cells, the ldlD.Lec1 mutants were highly resistant, and the Lec2 mutants required higher concentrations of Gal for inhibition. The E. histolytica Gal or GalNAc adherence lectin bound preferentially to beta 1-6-branched, N-linked carbohydrates lacking terminal sialic acid or fucose residues. However, amebic lectin binding to either N- or O-linked cell surface carbohydrates was sufficient to initiate parasite cytolytic activity.


Assuntos
Acetilgalactosamina/metabolismo , Adesão Celular , Entamoeba histolytica/metabolismo , Galactosamina/análogos & derivados , Galactose/metabolismo , Receptores Imunológicos/análise , Receptores Mitogênicos/análise , Animais , Configuração de Carboidratos , Linhagem Celular , Cricetinae , Cricetulus , Citotoxicidade Imunológica , Entamoeba histolytica/imunologia , Entamoeba histolytica/fisiologia , Feminino , Glicosilação , Mutação , Ovário
11.
J Clin Invest ; 80(5): 1238-44, 1987 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2890654

RESUMO

Entamoeba histolytica adheres to human colonic mucus, colonic epithelial cells, and other target cells via a galactose (Gal) or N-acetyl-D-galactosamine (GalNAc) inhibitable surface lectin. Blockade of this adherence lectin with Gal or GalNAc in vitro prevents amebic killing of target cells. We have identified and purified the adherence lectin by two methods: affinity columns derivatized with galactose monomers or galactose terminal glycoproteins, and affinity columns and immunoblots prepared with monoclonal antibodies that inhibit amebic adherence. By both methods the adherence lectin was identified as a 170-kD secreted and membrane-bound amebic protein. The surface location of the lectin was confirmed by indirect immunofluorescence. Purified lectin competitively inhibited amebic adherence to target cells by binding to receptors on the target Chinese hamster ovary cells in a Gal-inhibitable manner.


Assuntos
Assialoglicoproteínas , Entamoeba histolytica/fisiologia , Hemaglutininas/isolamento & purificação , Animais , Anticorpos Monoclonais , Ligação Competitiva , Adesão Celular , Linhagem Celular , Cromatografia de Afinidade , Cricetinae , Eletroforese em Gel de Poliacrilamida , Imunofluorescência , Galactose , Galectinas , Hemaglutininas/metabolismo , Técnicas Imunoenzimáticas , Técnicas Imunológicas , Orosomucoide/análogos & derivados
12.
Infect Immun ; 55(10): 2327-31, 1987 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2888730

RESUMO

Cure of amebic liver abscess is associated with resistance to recurrent invasive amebiasis and the development of a humoral and cell-mediated immune response. We determined whether human immune sera contain blocking antibody for the 170-kilodalton (kDa) galactose or N-acetylgalactosamine (Gal/GalNAc)-binding lectin of Entamoeba histolytica. By Western blot (immunoblot) of whole amebae subjected to sodium dodecyl sulfate-polyacrylamide gel electrophoresis, all eight immune sera studied here prominently recognized a 170-kDa amebic protein. Western blot of the purified Gal/GalNAc lectin with pooled human immune sera (PHIS) confirmed that the 170-kDa band was the adherence lectin. Immunoprecipitation of [35S]methionine-metabolically-labeled amebae with the antilectin monoclonal antibody H8-5 and with PHIS demonstrated that the 170-kDa lectin was the major antigen recognized by PHIS. The in vitro adherence of E. histolytica trophozoites to CHO cells at 4 degrees C was inhibited by prior exposure of amebae to greater than or equal to 1.0% PHIS. The humoral response to the Gal/GalNAc-binding lectin of the parasite may contribute to the development of protective immunity against invasive amebiasis.


Assuntos
Anticorpos Antiprotozoários/análise , Antígenos Glicosídicos Associados a Tumores , Dissacarídeos/imunologia , Entamoeba histolytica/imunologia , Lectinas/imunologia , Abscesso Hepático Amebiano/imunologia , Adesividade , Animais , Anticorpos Monoclonais , Antígenos de Protozoários/imunologia , Autorradiografia , Ligação Competitiva , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Humanos , Soros Imunes/análise , Soros Imunes/imunologia , Imunoensaio
13.
J Immunol ; 136(7): 2633-9, 1986 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-2869086

RESUMO

We studied the afferent and efferent cell-mediated immune response in 15 patients treated for amebic liver abscess. Patients had a lower T4 to T8 ratio (1.25 +/- 0.65) compared with age- and sex-matched controls (1.89 +/- 0.44, p less than 0.01) due to a decrease in T4-"helper" cells and an increase in T8-"suppressor" cells (p less than 0.01). The in vitro proliferative response of patient T lymphocytes to the plant mitogen concanavalin A (Con A) was depressed; responses to phytohemagglutinin were not. The proliferative response of patient lymphocytes to an amebic soluble protein preparation (SPP) was greater than the mitogenic response seen in control lymphocytes (mean of 68,300 delta cpm and 22,300 delta cpm, respectively, p less than 0.001), correlated with the T4 to T8 ratio (p less than 0.05) and the duration of time from initiation of antiamebic therapy (p less than 0.01). Supernatants from patient lymphocytes exposed to the amebic SPP activated normal monocyte-derived macrophages to kill virulent axenic E. histolytica trophozoites (p less than 0.001); patient monocyte-derived macrophages activated by Con A-elicited lymphokine could also kill amebae. Finally, when incubated with the amebic SPP for 5 days, T lymphocytes from patients were able to kill virulent amebae (p less than 0.005); patient T lymphocytes not exposed to the amebic SPP or control T lymphocytes incubated for 5 days with the amebic SPP were not cytotoxic to E. histolytica trophozoites. In summary, after cure of amebic liver abscess, specific cell-mediated immune mechanisms develop that are effective in vitro against the parasite.


Assuntos
Amebíase/imunologia , Entamoeba histolytica/imunologia , Entamebíase/imunologia , Imunidade Celular , Abscesso Hepático Amebiano/imunologia , Adulto , Idoso , Entamebíase/terapia , Feminino , Seguimentos , Interações Hospedeiro-Parasita , Humanos , Contagem de Leucócitos , Abscesso Hepático Amebiano/terapia , Ativação Linfocitária , Macrófagos/parasitologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Linfócitos T/classificação , Linfócitos T/parasitologia
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