RESUMEN
Appendiceal intussusception is described, in the surgical literature, as a rare entity with a 0.01% incidence (1). Presenting symptoms can be vague, and preoperative diagnosis is difficult. Given concerns about malignancy, complete surgical removal of the mass and histologic examination of the specimen are paramount, in order to ensure correct diagnosis and proper treatment. Herein, we describe the case of a 44-year-old woman with appendiceal endometriosis leading to intussusception.
RESUMEN
The nonstructural (ns) proteins nsP1 to -4, the components of Semliki Forest virus (SFV) RNA polymerase, were localized in infected cells by confocal microscopy using double labeling with specific antisera against the individual ns proteins. All ns proteins were associated with large cytoplasmic vacuoles (CPV), the inner surfaces of which were covered by small invaginations, or spherules, typical of alphavirus infection. All ns proteins were localized by immuno-electron microscopy (EM) to the limiting membranes of CPV and to the spherules, together with newly labeled viral RNA. Along with earlier observations by EM-autoradiography (P. M. Grimley, I. K. Berezesky, and R. M. Friedman, J. Virol. 2:326-338, 1968), these results suggest that individual spherules represent template-associated RNA polymerase complexes. Immunoprecipitation of radiolabeled ns proteins showed that each antiserum precipitated the other three ns proteins, implying that they functioned as a complex. Double labeling with organelle-specific and anti-ns-protein antisera showed that CPV were derivatives of late endosomes and lysosomes. Indeed, CPV frequently contained endocytosed bovine serum albumin-coated gold particles, introduced into the medium at different times after infection. With time, increasing numbers of spherules were also observed on the cell surfaces; they were occasionally released into the medium, probably by secretory lysosomes. We suggest that the spherules arise by primary assembly of the RNA replication complexes at the plasma membrane, guided there by nsP1, which has affinity to lipids specific for the cytoplasmic leaflet of the plasma membrane. Endosomal recycling and fusion of CPV with the plasma membrane can circulate spherules between the plasma membrane and the endosomal-lysosomal compartment.
Asunto(s)
ARN Viral/biosíntesis , Virus de los Bosques Semliki/genética , Virus de los Bosques Semliki/ultraestructura , Replicación Viral , Animales , Anticuerpos Antivirales , Biomarcadores/análisis , Línea Celular , Membrana Celular/ultraestructura , Membrana Celular/virología , Núcleo Celular/ultraestructura , Núcleo Celular/virología , Cricetinae , Citoplasma/ultraestructura , Citoplasma/virología , Técnica del Anticuerpo Fluorescente , Sustancias Macromoleculares , Microscopía Confocal , Microscopía Inmunoelectrónica , Pruebas de Precipitina , ARN Viral/genética , Virus de los Bosques Semliki/fisiología , Ensamble de VirusRESUMEN
BACKGROUND: An autoimmune etiology similar to the sympathetic ophthalmia has been discussed for sensorineural hearing loss on the last hearing ear following deafness in the first ear. In sympathetic cochleolabyrinthitis inner ear proteins are thought to be released after laterobasal fracture, which may induce an autoimmune process in the last hearing ear. Animal models have failed to clearly demonstrate the location of the target in the labyrinth, attacked by immunologic processes. Furthermore, it is unclear whether the humoral or cellular pathway is initiating this process. METHODS AND PATIENTS: Serum was acquired from 15 patients with traumatic or post-inflammatory unilateral deafness and slowly progressive or sudden sensorineural hearing loss on the last hearing ear. Deparaffinized sections of rat temporal bones were incubated with patient serum and subjected to immunohistochemical examination. RESULTS: A specific but heterogeneous binding pattern of the labyrinth was found in 14 of 15 patients. CONCLUSION: Our results indicate different autoantibodies in the patient serum, which may be the cause of the hearing loss. Therefore, in patients with sensorineural hearing loss on the last hearing ear, we recommend a therapeutic trial with corticosteroids.
Asunto(s)
Autoanticuerpos/sangre , Enfermedades Autoinmunes/diagnóstico , Sordera/inmunología , Oído Interno/inmunología , Pérdida Auditiva Sensorineural/etiología , Corticoesteroides/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Animales , Cóclea/inmunología , Sordera/etiología , Femenino , Pérdida Auditiva Sensorineural/tratamiento farmacológico , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Ratas , Ratas Wistar , Factores de TiempoRESUMEN
Antiserum prepared against an amino-terminal fragment of rubella virus (RUB) nonstructural polyprotein was used to study RUB-infected Vero cells. Replicase protein P150 was associated with vesicles and vacuoles of endolysosomal origin and later with large, convoluted, tubular membrane structures. Newly incorporated bromouridine was associated with the same structures and specifically with small membrane invaginations, spherules, indicating that these structures may be the sites of viral RNA synthesis.
Asunto(s)
ARN Polimerasa Dependiente del ARN/metabolismo , Virus de la Rubéola/enzimología , Proteínas no Estructurales Virales/metabolismo , Animales , Chlorocebus aethiops , Células HeLa , Humanos , Líquido Intracelular , Microscopía Confocal , ARN Viral/biosíntesis , Conejos , Células VeroRESUMEN
Semliki Forest virus replicase protein nsP2 shares sequence homology with several putative NTPases and RNA helicases. NsP2 has RNA-dependent NTPase activity. Here we expressed polyhistidine-tagged nsP2 in Escherichia coli, purified it by metal-affinity chromatography, and used it in RNA helicase assays. RNA helicase CI of plum pox potyvirus was used as a positive control. Unwinding of alpha-32P-labelled partially double-stranded RNA required nsP2, Mg2+ and NTPs. NsP2 with a mutation, K192N, in the NTP-binding sequence GVPGSGK192SA could not unwind dsRNA and had no NTPase activity. This is the first demonstration of RNA helicase activity within the large alphavirus superfamily.
Asunto(s)
Cisteína Endopeptidasas/metabolismo , ARN Helicasas/metabolismo , Virus de los Bosques Semliki/enzimología , Cisteína Endopeptidasas/genética , ARN Helicasas/genética , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Virus de los Bosques Semliki/genéticaRESUMEN
We studied 2 groups of women whose management is controversial: those with cervical intraepithelial neoplasia (CIN) grade 2 or 3 on smear, but only CIN grade 1 or no abnormality on target biopsy (Group 1), and those with persistent CIN grade 1 on smear and up to CIN 1 on biopsy (Group 2). We set out to assess whether large loop excision of the transformation zone (LLETZ) was an acceptable method of treating these 2 groups of women. A review of 100 consecutive patients was undertaken. There were 71 women in Group 1 and 29 women in Group 2. The LLETZ procedures were performed under local analgesia and no immediate problems were encountered. Delayed haemorrhage requiring vaginal packing and admission to hospital occurred in 1 patient. In Group 1, histopathology of the LLETZ biopsies showed CIN 2 or 3 in 29 (40.8%) of the women, CIN 1 in 24 (33.8%) and no CIN in 18 (25.3%), and in Group 2, CIN 2 or 3 was seen in 5 (17.2%) of the women, CIN 1 in 11 (37.9%) and no CIN in 13 (44.8%). At 12 months completed follow-up, 4 patients in Group 1 had recurrent CIN 1 or equivocal CIN 1 and 1 patient from Group 2 had recurrent CIN 1, giving an overall recurrence rate of 5 of the 94 patients who completed follow-up (5%). We concluded that LLETZ was a useful procedure in both groups. In Group 1 the provision of a histological diagnosis on the LLETZ biopsy was a check on the accuracy of the cervical smear report. In Group 2, LLETZ offered the advantage of rapidly returning the smear to normal in most patients, and the diagnosis and treatment of those women who actually had a high-grade lesion.
Asunto(s)
Displasia del Cuello del Útero/cirugía , Neoplasias del Cuello Uterino/cirugía , Adolescente , Adulto , Femenino , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estudios Retrospectivos , Neoplasias del Cuello Uterino/patología , Frotis Vaginal , Displasia del Cuello del Útero/patologíaRESUMEN
We evaluated three cardioplegic solutions, Bretschneider's cardioplegic solution (HTK), St. Thomas' Hospital solution (STH) and the solution of the National Institutes of Health (NIH), a solution with added nitroglycerin and lidocaine, for their ability to minimize ischemia-reperfusion injury in a working rat heart model. After cardioplegic arrest at 4 degrees C and subsequent 45 min of ischemic storage at 25 degrees C the function recovery of hearts was examined during 1 h of normothermic crystalloid reperfusion using Krebs-Henseleit buffer as perfusion medium. We noted a significantly better preservation of the maximum (+dp/dt(max)) and minimum (-dp/dt(max)) velocity of pressure development and a significantly higher coronary flow with the use of HTK (2,657 mm Hg/s, 2,122 mm Hg/s, 17 ml/min) compared to STH (1,600 mm Hg/s, p < 0.05; 1,591 mm Hg/s, p<0.05; 11 ml/ min, p<0.05), and an intermediate level of preservation of hemodynamic parameters with NIH (2,149 mm Hg/s, 1,766 mm Hg/s, 12 ml/min). Concerning the cardiac output, however, no major difference was found between the HTK (41 ml/min), the STH (34 ml/min) and the NIH group (36 ml/min). The decay of the myocardial energy charge was significantly lower in both the HTK and the NIH group as compared with conservation in STH solution. Lactate was lowest in the HTK group, CK and LDH releases in the effusate remained lowest after HTK and NIH preservation. The data of this study suggest that HTK and NIH most perfectly reduce the impairment of myocardial function and provide better myocardial protection during ischemic arrest at 25 degrees C and superior recovery compared to STH solution.
Asunto(s)
Soluciones Cardiopléjicas/farmacología , Paro Cardíaco Inducido , Animales , Bicarbonatos/farmacología , Cloruro de Calcio/farmacología , Metabolismo Energético , Glucosa/farmacología , Magnesio/farmacología , Masculino , Manitol/farmacología , Miocardio/metabolismo , Cloruro de Potasio/farmacología , Procaína/farmacología , Ratas , Ratas Sprague-Dawley , Cloruro de Sodio/farmacología , Función Ventricular IzquierdaRESUMEN
A dye-binding procedure was developed for the analysis of protein attached to the membrane, with bound and adsorbed forms of attachment being distinguished. The relationship between modification procedure and protein attachment was explored and related to flux, streaming potential, and rejection with variation of pH. The effects of attaching four different types of gelatin to the membrane were studied. Assessment was made of modifications for improvement of flux and selectivity in the presence of protein foulants.
Asunto(s)
Gelatina , Membranas Artificiales , Ultrafiltración/instrumentación , Animales , Biotecnología , Bovinos , Colorantes , Electroquímica , Caballos , Concentración de Iones de Hidrógeno , Mioglobina/aislamiento & purificación , Polímeros , Unión Proteica , Albúmina Sérica Bovina/aislamiento & purificación , Sulfonas , AguaRESUMEN
The objective of this study was to assess the protective capacity of UW solution in comparison to Bretschneider's (HTK) cardioplegic solution under moderate hypothermic conditions (25 degrees C), as those usually present during intraoperative myocardial protection. Ischemia-induced alterations of cardiac function parameters were analyzed and compared for each solution after 45 min of ischemic storage and 60 min of reperfusion with oxygenated Krebs-Henseleit buffer (KHB), using a rat working-heart model. Compared to nonischemic values, left-ventricular systolic and diastolic pressure, +dp/dtmax and -dp/dtmax were significantly better maintained in the HTK (95 mm Hg, 7 mm Hg, 2,657 mm Hg/s and 2,122 mm Hg/s) than in the UW group (76 mm Hg, p < 0.05, 11 mm Hg, p < 0.05, 1,745 mm Hg/s, p < 0.05 and 1,600 mm Hg/s, p < 0.05). Concerning the myocardial contents of ATP, creatine phosphate and the energy charge, a minor decrease was observed after preservation in HTK compared to UW solution. The results of this study indicate superior myocardial protection with the use of HTK solution for protection of the heart at 25 degrees C compared to UW solution.
Asunto(s)
Paro Cardíaco Inducido , Corazón/fisiología , Soluciones Preservantes de Órganos , Preservación de Órganos , Adenosina/farmacología , Alopurinol/farmacología , Animales , Metabolismo Energético , Glucosa/farmacología , Glutatión/farmacología , Hemodinámica , Insulina/farmacología , Masculino , Manitol/farmacología , Cloruro de Potasio/farmacología , Procaína/farmacología , Rafinosa/farmacología , Ratas , Ratas Sprague-DawleyRESUMEN
Tumor necrosis factor (TNF) and lymphotoxin (LT), initially described as tumoricidal proteins, may be useful as adjuncts in cancer therapy. Treatment with TNF or LT was found to protect cells and animals against damage mediated by radiation or cytotoxic anticancer drugs. By contrast, tumor cells treated with TNF or LT were sensitized to these insults. We present a model in which TNF or LT induces both the synthesis of "protective" proteins such as manganous superoxide dismutase (MnSOD) and the activation of "killing" proteins, such as proteases, depending on the level of the inducing signal. Although the p55-TNF/LT receptor is structurally related to the Fas receptor, they can each signal apoptosis by distinct pathways. Furthermore, activation of both receptors acts synergistically in stimulating apoptosis.
Asunto(s)
Apoptosis , Linfotoxina-alfa/uso terapéutico , Neoplasias/terapia , Factor de Necrosis Tumoral alfa/uso terapéutico , Animales , Apoptosis/efectos de los fármacos , Apoptosis/efectos de la radiación , Inducción Enzimática , Proteína Ligando Fas , Humanos , Glicoproteínas de Membrana/inmunología , Neoplasias/patología , Superóxido Dismutasa/biosíntesisRESUMEN
BACKGROUND: Neutrophils have been shown to play a role in ischemia-reperfusion injury, and the initial interaction of neutrophils with the endothelium is mediated through the selectin family of adhesion molecules. Thus the purpose of these studies was to determine whether a P-selectin-IgG chimera was protective in a model of ischemia-reperfusion injury. METHODS: The model used was a rabbit ear model of ischemia-reperfusion. Selectin-IgG chimeras were given at the time of reperfusion of the tissue, and their efficacy was compared with an anti-CD18 antibody (MHM23). RESULTS: The P-selectin-IgG was as protective in this model as an anti-CD18 antibody. The chimera did not mediate its effect by causing the animals to become neutropenic. CONCLUSIONS: P-selectin plays a role in ischemia-reperfusion injury. This is in agreement with data from other groups. The fact that the chimera was effective in this model suggests that carbohydrates or small molecule mimics of carbohydrates would be effective in this model. Such antiinflammatory agents may have fewer side effects in terms of increased risk of sepsis.
Asunto(s)
Inmunoglobulina G/uso terapéutico , Isquemia/fisiopatología , Glicoproteínas de Membrana Plaquetaria/uso terapéutico , Proteínas Recombinantes de Fusión/uso terapéutico , Daño por Reperfusión/prevención & control , Animales , Antígenos CD18/inmunología , Moléculas de Adhesión Celular/uso terapéutico , Oído , Endotelio Vascular/fisiopatología , Isquemia/patología , Masculino , Neutrófilos/fisiología , Selectina-P , Conejos , Daño por Reperfusión/patologíaRESUMEN
Fractionation of the model proteins, bovine serum albumin and myoglobin, was studied with modified and unmodified polysulfone ultrafiltration membranes. A commercial polysulfone ultrafiltration membrane with a nominal cut-off value of 50,000 g mol-1 was used as the reference membrane, and it was modified with ultraviolet irradiation in different protein solutions. The permeate fluxes and the streaming potentials of the membranes were measured simultaneously. Ultrafiltration experiments were carried out at the isoelectric points of the proteins. The results show that the fractionation can best be carried out at the isoelectric point of myoglobin. Modification of the membranes with bovine serum albumin resulted in smaller adsorption and flux reduction, while membranes modified with myoglobin were more selective for myoglobin.
Asunto(s)
Mioglobina/aislamiento & purificación , Albúmina Sérica Bovina/aislamiento & purificación , Ultrafiltración/métodos , Animales , Biotecnología , Bovinos , Estudios de Evaluación como Asunto , Caballos , Concentración de Iones de Hidrógeno , Membranas Artificiales , Polímeros , Sulfonas , Ultrafiltración/instrumentación , Rayos UltravioletaRESUMEN
The vascular selectins P- and E-selectin are inducible adhesion proteins expressed by endothelial cells that have been shown to support shear-dependent rolling of myeloid cells. This interaction is thought to be a prerequisite event for subsequent steps, such as tight adhesion/aggregation and transendothelial cell migration, involved in the accumulation of leukocytes into tissues. Certain lymphocyte subsets have also been shown to bind the vascular selectins, but the importance of this interaction in mediating shear-dependent rolling, as described for myeloid cells, has not been demonstrated. We expand on our earlier observation that bovine gamma/delta T cells bind E-selectin by showing that this interaction leads to a reproducible rolling event in assays done under shear forces that approximate those that occur in vivo. E-selectin, expressed by L cell transfectants or cytokine-stimulated human and bovine endothelial cells, equally supports the shear-dependent rolling interaction. The lymphocyte adhesion proteins L-selectin, CD44, and CD2 do not contribute to this event. Neuraminidase treatment of the gamma/delta T cells or addition of EDTA to the assay completely blocks the rolling interaction. We further show for the first time that P-selectin expressed by thrombin-activated platelets or a soluble P-selectin/human Ig chimera specifically binds gamma/delta T cells. The P-selectin interaction is similar to the rolling event mediated by E-selectin--it requires divalent cations and sialic acid on the lymphocyte, it lacks involvement of L-selectin and CD44, and rolling occurs under physiologic shear conditions. These results provide the documentation that the vascular selectins can support shear-dependent rolling of a lymphocyte subset and that P-selectin mediates the adhesion of gamma/delta T cells.
Asunto(s)
Moléculas de Adhesión Celular/fisiología , Glicoproteínas de Membrana Plaquetaria/fisiología , Receptores de Antígenos de Linfocitos T gamma-delta/inmunología , Subgrupos de Linfocitos T/fisiología , Animales , Anticuerpos Monoclonales/inmunología , Plaquetas/fisiología , Bovinos , Citocinas/fisiología , Selectina E , Citometría de Flujo , Células L/fisiología , Ratones , Ratones Endogámicos BALB C , Selectina-P , TransfecciónRESUMEN
Wound healing and other inflammatory processes are driven by a complex series of interactions among cells, the extracellular matrix, and secreted products of various cell types. Cytokines, such as interleukin-1 and transforming growth factor-alpha, are present at wound sites and contribute to the proinflammatory milieu of these sites. In the present study, we have investigated the effect of these cytokines, individually and in concert, on fibroblast expression of matrix metalloproteinases, which contribute to extracellular matrix remodeling, and of prostaglandin E2, which alters vascular tone and permeability. The metalloproteinases, procollagenase (matrix metalloproteinase-1) and prostromelysin (matrix metalloproteinase-3), are induced by exposure of dermal fibroblasts to interleukin-1, not stimulated by transforming growth factor-alpha, but are synergistically induced by the combination of cytokines. The 92-kDa type IV procollagenase (matrix metalloproteinase-9, progelatinase B), is also stimulated in synergistic fashion. Prostaglandin E2 is induced in rheumatoid synovial fibroblasts by interleukin-1 beta, not altered by transforming growth factor-alpha, and is synergistically released by the combination of the two cytokines. Fibroblast proliferation, which is also a component of normal wound healing, is also synergistically stimulated by the action of the two cytokines in concert. These results indicate that interleukin-1 beta and transforming growth factor-alpha synergize to elicit a number of phenotypic responses in fibroblasts which are relevant to normal wound healing and chronic inflammation.
Asunto(s)
Dinoprostona/metabolismo , Interleucina-1/farmacología , Metaloendopeptidasas/biosíntesis , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Factor de Crecimiento Transformador alfa/farmacología , Artritis Reumatoide/metabolismo , Artritis Reumatoide/patología , División Celular/efectos de los fármacos , Células Cultivadas , Colagenasas/análisis , Colagenasas/biosíntesis , ADN/biosíntesis , Sinergismo Farmacológico , Inducción Enzimática , Precursores Enzimáticos/análisis , Precursores Enzimáticos/biosíntesis , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Expresión Génica/efectos de los fármacos , Humanos , Metaloendopeptidasas/análisis , Peso Molecular , ARN Mensajero/biosíntesis , Valores de Referencia , Piel/citología , Piel/efectos de los fármacos , Piel/metabolismo , Membrana Sinovial/efectos de los fármacos , Timidina/metabolismo , Transcripción Genética/efectos de los fármacosRESUMEN
Human atheromas accumulate extracellular matrix proteins such as collagen types I and III. We tested whether cytokines or growth factors produced by cells found in human atherosclerotic plaques alter collagen gene expression in vascular smooth muscle cells (VSMCs), which produce the blood vessel matrix. Interleukin-1 (IL-1, 1-10 ng/ml) modestly increased the synthesis of collagens I and III (measured by tritiated proline incorporation into specific electrophoretic bands), whereas transforming growth factor-beta (TGF-beta) or platelet-derived growth factor (PDGF) markedly stimulated production of these interstitial collagens. Interferon gamma (IFN-gamma), a product of activated T cells found in atheromas, selectively alters several VSMC functions. For example, this cytokine reduces growth of VSMCs, decreases alpha-actin gene expression, and induces VSMC expression of class II histocompatibility antigens. We report here that IFN-gamma also inhibits basal as well as IL-1-, PDGF-, or TGF-beta-stimulated collagen I and III synthesis by human VSMCs. TGF-beta, the most potent stimulator of collagen synthesis studied here, raised the level of collagen III mRNA in VSMCs 4.8-fold (determined by densitometry of Northern blots), whereas exposure to both TGF-beta and IFN-gamma reduced this mRNA to 0.5 of basal level. Locally produced cytokines and growth factors may thus modify matrix accumulation during atherogenesis by stimulating or suppressing expression of interstitial collagen mRNA and protein by VSMCs.