Autoimmunity and molecular mimicry in tropical spastic paraparesis/human T-lymphotropic virus-associated myelopathy.

Viruses share antigenic sites with normal host cell components, a phenomenon known as molecular mimicry. It has long been suggested that viral infections might trigger an autoimmune response by several mechanisms including molecular mimicry. More than 600 antiviral monoclonal antibodies generated against 11 different viruses have been reported to react with 3.5% of cells specific for uninfected mouse organs. The main pathological feature of tropical spastic paraparesis/human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (TSP/HAM) is a chronic inflammation of the spinal cord characterized by perivascular cuffing of mononuclear cells accompanied by parenchymal lymphocytic infiltration. We detected the presence of autoantibodies against a 98- to 100-kDa protein of in vitro cultured human astrocytes and a 33- to 35-kDa protein from normal human brain in the serum of HTLV-I-seropositive individuals. The two cell proteins exhibited molecular mimicry with HTLV-I gag and tax proteins in TSP/HAM patients, respectively. Furthermore, the location of 33- to 35-kDa protein cross-reaction correlated with the anatomical spinal cord areas (in the rat model) in which axonal damage has been reported in several cases of TSP/HAM patients. Our experimental evidence strongly suggests that the demyelinating process occurring in TSP/HAM may be mediated by molecular mimicry between domains of some viral proteins and normal cellular targets of the spinal cord sections involved in the neurodegeneration.

Autoimmunity and molecular mimicry in tropical spastic paraparesis/human T-lymphotropic virus-associated myelopathy

Viruses share antigenic sites with normal host cell components, a phenomenon known as molecular mimicry. It has long been suggested that viral infections might trigger an autoimmune response by several mechanisms including molecular mimicry. More than 600 antiviral monoclonal antibodies generated against 11 different viruses have been reported to react with 3.5 percent of cells specific for uninfected mouse organs. The main pathological feature of tropical spastic paraparesis/human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (TSP/HAM) is a chronic inflammation of the spinal cord characterized by perivascular cuffing of mononuclear cells accompanied by parenchymal lymphocytic infiltration. We detected the presence of autoantibodies against a 98- to 100-kDa protein of in vitro cultured human astrocytes and a 33- to 35-kDa protein from normal human brain in the serum of HTLV-I-seropositive individuals. The two cell proteins exhibited molecular mimicry with HTLV-I gag and tax proteins in TSP/HAM patients, respectively. Furthermore, the location of 33- to 35-kDa protein cross-reaction correlated with the anatomical spinal cord areas (in the rat model) in which axonal damage has been reported in several cases of TSP/HAM patients. Our experimental evidence strongly suggests that the demyelinating process occurring in TSP/HAM may be mediated by molecular mimicry between domains of some viral proteins and normal cellular targets of the spinal cord sections involved in the neurodegeneration.

Localización histoquímica e inmunohistoquímica de fibrocitos en la cóclea de la rata / Histochemical and immunohistochemical location of fibrocyts in the cochlea of rats

El fibrocito, célula de origen mesenquimal del ligamento espiral de la coclea, ha sido investigado usando tecnicas inmunohistoquimicas que al intentar reproducirlas fallan debido a la impredecible alteracion de sitios antigenicos introducidos durante el procesamiento de la muestra. El presente estudio describe la estandarizacion de una tecnica histoquimica e inmunohistoquimica para la localizacion del fibrocito en la coclea de la rata. Dos ejemplares, bajo anestesia general con nembutal recibieron una inyeccion intracardiaca de fijadores tipo aldehidos, buffer salino fosfato y sales precipitantes. Luego de la muerte del animal su cabeza se sometio a postfijacion y decalcificacion, para realizarle cortes con microtomo cada 5 micrometros y tincion cada decima placa con hematoxilina-eosina. Finalmente, se utilizó inmunohistoquimica indirecta con el metodo Avidina-biotina conjugada y marcador monoclonal anti-vimentina y la proteina S100, lográndose la identificacion de los fibrocitos y demás componentes del organo de corti murino. La estandarizacion de esta tecnica es un hecho trascendental para el proceso de investigacion histopatologica del oido interno, aplicable al estudio de patologias que afecten a los fibrocitos del ligamento espiral

HIV disease and pregnancy. Part 3. Postpartum care of the HIV-positive woman and her newborn.

For women with HIV infection, physical and psychosocial adaptation during the postpartum period is fraught with ambivalence. On the one hand, there is the joy of parenthood, but on the other, the burden of a chronic, terminal illness and the possibility of having an infected newborn. The nursing care of the HIV-positive woman and her newborn is discussed. Guidelines for hospital discharge teaching are included.

HIV disease and pregnancy. Part 1. Epidemiology, pathogenesis, and natural history.

Women constitute the fastest growing component of the human immunodeficiency virus (HIV) epidemic. The majority of women with HIV disease are of reproductive age, and perinatally acquired HIV infection has increased proportionately. The nurse needs knowledge about the unique interactions between HIV infection and pregnancy to provide the complex care required during the perinatal period. An overview of the epidemiology, pathogenesis, and natural history of HIV disease focusing on women is presented. The effects of pregnancy on the progression of HIV disease and the effects of HIV disease on pregnancy outcomes are explored.

[Disorders of the heart rhythm in the immediate postoperative period in patients who have undergone vascular surgery]. / Trastornos del ritmo cardíaco en el posoperatorio inmediato en los pacientes sometidos a cirugía vascular.

Heart rate changes during the immediate postoperative period were studied in 190 patients that underwent revascularization surgery. At the same time, other cardiovascular complications in those patients were analyzed. In 89 patients (46.8%), cardiovascular antecedents were found. Ischemic heart disease was found in 84 patients (44.2%). The most common cardiac arrhythmia was found to be sinus tachycardia, which was seen in 87 patients (45.7%). Following in order of frequency were supraventricular extrasystoles together with ventricular extrasystoles in 18 patients (9.4%) and isolated ventricular extrasystoles in 16 (8.4%). The most common cardiovascular and hemodynamic complications, both associated and as predisposing causes, were high blood pressure in isolation or combined with heart failure found in 58 (30.5%) and 8 (4.3%) patients, respectively. Hypokalemia played an important role since it was found in 105 patients (55.3%), 90 of whom had cardiac arrhythmia (85.7%). Seven revascularized patients (3.7%) died due to cardiovascular causes.

[Bacteriological studies of the secretions obtained from the endotracheal tube removed from patients recently revascularized]. / Estudios bacteriológicos de las secreciones obtenidas del tubo endotraqueal retirado a los pacientes recién revascularizados.

In cultures of secretions from 101 distal ends of endotracheal tubes removed from patients recently operated on due to several vascular affections, 41.6% of them were positive to different germs: pathogenic (7.9%), potentially pathogenic (12.9%), habitual in the oropharynx (3.9%), opportunistic (4.9%), contaminating (0.9%). Out of the 18.8% of patients recently operated on for acute inflammatory pneumopathy, 68.4% of them had positive cultures of the secretions in the distal ends of the removed endotracheal tubes. Hemocultures were carried out in 34.7% of the patients and 17.1% of them were found positive, although the germs found in the endotracheal tubes and the hemocultures were different. In the immediate postoperative period 48.5% of the gastric pH test were carried out and it was found that 37.6% of them were lower than 4, and 10.9% were higher than 4.1. Among the diseased, 28.6% had acute inflammatory pneumopathy and positive cultures of the secretions in the endotracheal tubes removed.