Dilataciones endoscópicas del tracto gastrointestinal / Endoscopic dilation of the gastrointestinal tract

Las dilataciones en el tracto gastrointestinal se llevan a cabo para aliviar la obstrucción sintomática, ya sea funcional u orgánica, secundarias a una variedad de patologías tanto benignas como malignas. Con el advenimiento de las nuevas tecnologías, virtualmente toda estenosis digestiva puede ser manejada en forma mínimamente invasiva. Pese a su amplia difusión en la práctica actual, existen pocos estudios controlados que comparen las diferentes modalidades de dilatación. En el presente artículo realizamos una revisión de esta técnica, así como de la evidencia disponible para su aplicación en los diferentes segmentos del tracto gastrointestinal. El futuro de la dilatación incluye el desarrollo de dilatadores que permitan evaluar la dilatación durante su realización. Estos advenimientos, así como la ejecución de estudios controlados prospectivos van a mejorar las indicaciones, beneficios y riesgos para cada uno de los sistemas de dilatación existentes.

The endoscopic dilation of the gastrointestinal tract is carried out to relieve either functional or organic disorders, secondary to a variety of both benign and malignant diseases. With the advent of new technologies, virtually all digestive stenosis can be managed in a minimally invasive way. Despite its wide dissemination in actual practice, there are few controlled studies comparing the different forms of endoscopic dilation. In this article, we review this technique and the evidence available for application in different segments of the gastrointestinal tract. The future of the dilations includes the development of dilators to assess dilation during the procedure. These advents and the implementation of prospective controlled studies will improve the indications, benefits and risks for each of the existing systems of dilations.

Polimorfismo Val247Leu do gene β2-glicoproteína 1 pode justificar a gênese de anticorpos antiβ2GP1 e síndrome do anticorpo antifosfolípide na hanseníase multibacilar / Val247Leu polymorphism of β2 glycoprotein 1 gene may justify the genesis of anti β2GP1 antibodies and Antiphospholipid Syndrome in Multibacillary Leprosy

FUNDAMENTOS - Anticorpos antifosfolípides (AAF), como antiβ2GP1 (β2-glicoproteína 1), são descritos na hanseníase multibacilar (MB) sem, contudo, caracterizar a síndrome do anticorpo antifosfolípide (SAF), constituída por fenômenos tromboembólicos (FTE). A mutação Val247Leu no V domínio da β2GP1 - substituição da leucina por valina - expõe epítopos crípticos com consequente formação de anticorpos antiβ2GP1. OBJETIVO: Avaliar a associação do polimorfismo Val247Leu do gene β2GP1 com títulos de anticorpos antiβ2GP1 na hanseníase. MÉTODO: O polimorfismo Val247Leu foi detectado por PCR-RFLP, e os títulos de anticorpos antiβ2GP1, por Elisa. RESULTADOS: O genótipo Val/Val estatisticamente predominou no grupo de hansênicos, em relação ao controle. Embora maiores títulos de anticorpos antiβ2GP1 IgM estivessem alocados no grupo MB com genótipos Val/Val e Val/Leu, não houve diferença estatística em relação ao genótipo Leu/Leu. Dos sete pacientes MB com FTE, quatro apresentaram heterozigose, e três Val/Val homozigose. CONCLUSÃO: A prevalência do genótipo Val/Val no grupo de hansênicos pode justificar parcialmente a presença de anticorpos antiβ2GP1 na forma MB. A heterozigose ou homozigose Val/Val nos sete pacientes com hanseníase MB e FTE corroboram a implicação de expressão fenotípica anômala da β2GPl e formação de anticorpos antiβ2GPl, com consequente FTE e SAF.

BACKGROUND - Multibacillary (MB) leprosy may be manifested with antiphospholipid antibodies (aPL), among which anti-β2GP1 (β2-glycoprotein 1). High titers of aPL are associated with APS (Antiphospholipid Syndrome), characterized by thrombosis. The mutation Val247Leu in the domain V of β2GP1 exposes hidden epitopes with consequent development of anti-β2GP1 antibodies. OBJECTIVE: To evaluate the Val247Leu polymorphism of β2GP1 gene and its correlation with anti-β2GP1 antibodies in leprosy patients. METHODS: The Val247Leu polymorphism was performed by PCR-RFLP and anti-β2GP1 antibodies were measured by ELISA. RESULTS: The genotypic Val/Val was more prevalent in the leprosy group, compared to controls. Regarding the 7 MB patients with APS, four presented heterozygosis and three, Val/Val homozygosis. Although higher titrations of anti-β2GP1 IgM antibodies were seen in MB leprosy group with Val/Leu and Val/Val genotypes, there was no statistical difference when compared to Leu/Leu genotype. CONCLUSION: The prevalence of Val/Val homozygosis in leprosy group can partially justify the presence of anti-β2GP1 IgM antibodies in MB leprosy. The description of heterozygosis and Val/Val homozygosis in 7 patients with MB leprosy and thrombosis corroborates the implication of anomalous phenotype expression of β2GP1 and development of anti-β2GP1 antibodies, with consequent thrombosis and APS.

Red cell immunization in multiply transfused Malay thalassemic patients.

The development of red blood cell (RBC) isoimmunization with alloantibodies and autoantibodies complicate transfusion therapy in multiply transfused thalassemia patients. Thus, the frequency, causes and prevention of these phenomena were studied among these patients. Clinical and serological data from 58 Malay multiply transfused thalassemic patients who sought treatment at Hospital University Sains Malaysia were collected and analyzed prospectively. Blood samples were subjected to standard blood bank procedures to screen for antibody and subsequent antibodies identification. All patients in our hospital received blood matched for only ABO and Rh (D) antigens. There were 46 (79.3%) patients with Hb E/beta thalassemia, 8 (13.8%) with beta thalassemia major, 3 (5.2%) with Hb H Constant Spring and 1 (1.7%) with Hb H disease. Overall, 8.6% of the patients had alloantibodies and 1.7% had autoantibodies. The alloantibodies identified were anti-E, anti-c, anti-K, anti-Jka, anti-N and anti-S. In conclusion, the transfusion of matched blood is essential for chronically multiply transfused patients in order to avoid alloimmunization. Considering the high frequency of anti E at our hospital, it is advisable to genotype patients and match the red cells for E antigens in multiply transfused thalassemia patients.

Interet du dosage anticorps antirecepteurs a la tsh

TSH receptor antibodies [TRAB] was performed by binding assay in seventy-seven patients [47 with Graves disease, 32 with other thyroid abnormalities] the sensitivity and specificity of our assay were respectively 81% and 96.5% these resultrs were similar to the results found in medical literature. The association of ophthalmopathy with Graves disease does not increase the sensitivity of the test. In this study we conclude that TRAB assay is of great interest in confirming the diagnosis and in the following of Graves disease

Autoanticuerpos, ¿sondas moleculares vigentes? su utilización en el reconocimiento de subdominios celulares denominados "cuerpos enrollados" (CE) / Autoantibodies, are they molecular probes validity?. Use in the coiled bodies identification

Los autoanticuerpos han sido utilizado como sondas moleculares desde principios de los 60, lo que ha permitido conocer y definir múltiples componentes funcionales celulares relacionados con mecanismos básicos de expresión genómica. Así, los autoanticuerpos anti-Sm, se asocian con pequeños RNAs nucleares (snRNA) que participan en el procesamiento del pre-RNAm, los anticuerpos anti-fibrilarina que identifican a pequeños RNAs nucleolares (snoRNA) y que han mostrado participar en el procesamiento del pre-RNAr. Recientemente, por ensayos de IFI y microscopía electrónica utilizando autoanticuerpos y oligonucléotidos sintéticos complementarios con algunos snRNA y/o snoRNAs, ha sido descrito que el subdominio nuclear celular denominado Cuerpo Enrollado (C.E.), se encuentra constituído por snRNA U1, U2, U4; U5, U6, snoRNA U3, detectándose algunos factores proteicos de splicing. Estos C.E poseen una proteína que los caracteriza y que se denomina p80 coilina. Se han descrito múltiples componentes para estos C.E.; sin embargo, su papel funcional celular no está definido

Factores involucrados en la facilitación de la respuesta autoinmune de animales envejecidos / Factors involved in the enhancement of the autoinmune response in aging rats

Se demostró que el envejecimiento facilita la inducción de respuesta autoinmune contra glándulas accesorias sexuales masculinas de ratas (GA) y, además, que las células de bazo de animales de 12 meses fueron capaces de transferir el fenómeno a animales de 3 meses. En este trabajo se analizó el tipo celular involucrado en la mayor respuesta como así también la influencia del medio interno. Los estudios se realizaron mediante experimentos de transferencia de células y posterior inmunización de los receptores con autoantígenos (GA químicamente modificado) y heteroantígeno (albumina sérica humana ASH) incorporado en coadyuvante de Freund completo. la respuesta de DTH nivel de anticuerpo contra GA demostraron que las células monocleares de bazo están comprometidas en la facilitación de la respuesta. Estas células separadas en poblaciones enriquecidas en linfocitos T o B pierden esa capacidad. En cambio, la población enriquecida en macrófago transfirió un nível significativo de respuesta autoinmune, lográndose la transferencia total sólo con los tres tipos celulares juntos. La transferencia de células a ratas previamente irradiadas aportó evidencias del compromiso del medio interno del animal de 12 meses isoinmunizado a ASH no mostró diferencias entre los distintos grupos experimentales

Autoantibodies and inmunocomplexes in Chagas' disease / Autoanticuerpos e inmunocomplejos en la enfermedad de Chagas

The presence of an autoimmune process mediated by antibodies in Chagas'disease was evaluated by studying EVI antibodies, immune complexes (Clq binding) and anti-DNA antibodies in serum samples from patients with Chagasic infection (Group I), Chagasic infection and Chagasic cardiomyopathy (Group II) and normal Venezuelan blood back donors (Group III). The study was performed on both single serum samples and those obtained longitudinally. With simgle samples the incidence of positivity for EVI antibodies was higher in Group II patients (87.5%) than in Group I (66.6%). However, with the serum samples from a longitudinal study the incidence of patients with persistently positive EVI antibodies was the same in both groups (43%). No relationship coul be established between the incidence of EVI antibodies and eiter the clinical status or the detection of circulating parasites by xenodiagnosis. The immunoglobulin fraction carryng the EVI antibodies was identified as IgG.Higher values of circulating immune comlexes were found in serum samples from patients with Chagasic cardiomyopathy. However no patient from the longitudinal study showed a persistently high Clq binding activity. The levels of anti-DNA antibodies were not different between the groups studied. It was concluded that no evidence was found to link the presence of EVI or other auto-reactive antibodies with heart damage in Chagas'disease

Experimental Nephritis Induced by Homologous Placental Tissue as Observed with the Light, Fluorescent and Electron Microscope

Toxemia of pregnancy is a common complication of gestation, usually occurring in late pregnancy. Whether toxemia represents an exaggeration of changes incident to pregnancy or depends upon some wholly new factor is a moot point. Indeed, the cause of the toxemia of pregnancy, despite decades of intensive research, remains the great enigma of obstetrics and constitutes one of an important unsolved problems in the field of human reproduction. Glomerulonephritis can be induced in various animal species by numerous serums and tissue extracts. Its production by duck immune serum was first described in the rabbit by Masugi(1934). By using a potent standardized nephrotoxic duck serum or its gamma globulin, nephritis has be reproduced in a regular manner by Seegal, et al., (1936). The experiments recorded here show the results of injecting rabbit antidog-placenta serum into both pregnant and non-pregnant dogs as described by Seegal at al., (1955). The course of the resulting nephritis is compared with that following the injection of rabbit antidog-kidney serum. The large size of the animal permitted frequent bleeding and the gestation period allowed for observation of nephritis during pregnancy. The findings support the conclusion that rabbit antidog-placenta serum injected in the dog produced an acute nephritis which usually progressed to a chronic state comparable to that which follows the injection of anti-kidney serum. Pregnancy has not been terminated by this antiserum. Beveans et al.(1955) describe the lesions produced in these pregnant and non-pregnant dogs following injection of either rabbit anti-placenta or rabbit anti-kidney serum. Acute and chronic phases of the nephritis have been studied over a period of 10 months. The intravenous injection of rabbit antidog-placenta or antidog-kidney serum produced immediate evidence of glomerulonephritis in dogs and rabbits. The glomerulonephritis so induced may terminate in death within 8 days, may progress to a chronic form or may heal. Recently, Irino et al.(1967) induced renal 1esions in rats by placental extracts. These changes were observed with the electron microscope and the ranal glomerular alterations in rats with a clinical syndrome resembling toxemia of pregnancy showed the characteristic changes consisting of swelling with decreased density of tile basement membrane, a dense granular deposition within tile along capillary basement membranes, and marked swelling and slight proliferation of glomerular epithelium. The glomerular lesions, designated endothelial glomerulitis are apparently a result of an antigen-antibody reaction and present further evidence that human toxemia of pregnancy has an immune mechanism as a basis for its production. Kim(1969) attempted to establish the pathologic changes induced by sensitizing the rat against homologous placental tissue and to compare them with the lesions of the kidney in human toxemia. He found that renal lesions were closely related to that of human toxemia of pregnancy. The present investigation is aimed to study the lesions in the glomerulus of the pregnant rat kidneys induced by repeated injection of homologous placental tissue as observed with the light, the fluorescent and the electron microscope and adds further evidence for the view that the syndrome, as induced experimentally, constitutes an analog of toxemia of pregnancy as it affects the human.s