RESUMEN
A clinically, immunohistochemically and ultrastructurally characterized series of 192 pituitary adenomas was analyzed for DNA content by flow cytometry. Results were assessed not only relative to tumor immunotype, size, and invasiveness, but also with frequency of recurrence. Case selection was non-random; males predominated (1.8:1) and the ratio of macro-to-microadenomas was 4.2:1. Female patients were slightly younger and, in all adenoma categories, less often had invasive tumors: PRL (15%/30%), ACTH (17%/44%), LH/FSH (8%/27%) and null cell adenomas (0%/27%). With the exception of prolactin cell adenomas, similar proportions of macroadenomas and invasive tumors in all tumor subtypes were diploid and non-diploid. Prolactin adenomas differed in that tumors of males showed a high rate of non-diploidy (65%); such tumors were predominantly macroadenomas, but only 28% were invasive. Among GH-containing tumors 78% were macroadenomas, 40% were nondiploid, and the frequency of invasive macroadenomas was higher (49%) than in PRL tumors (21%). ACTH adenomas were mainly microadenomas (81%), their rate invasion (29%) and of non-diploidy being low (14%). Among "non-functioning" (LH/FSH, null cell adenomas), LH/FSH-producing tumors were all macroadenomas, but with low rates of invasion (23%) and non-diploidy (9%). Null cell adenomas, nearly all macroadenomas, had similar low invasion rate (21%), but were more often non-diploid (39%). In all adenoma subgroups S-phase fractions were higher in non-diploid adenomas by an overall ratio of 2.1:1. Prolactin adenomas showed the highest (15.2%) and LH/FSH adenomas the lowest (5.6%) mean S-phase fraction. When compared to long-term follow-up, neither this parameter nor ploidy correlated with tumor size or invasiveness. Lastly, long-term follow-up showed ploidy to be an unreliable predictor of tumor persistence or recurrence.
Asunto(s)
Adenoma/genética , Adenoma/metabolismo , ADN/metabolismo , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/metabolismo , Ploidias , Adenoma/patología , Hormona Adrenocorticotrópica/metabolismo , Femenino , Citometría de Flujo , Gonadotropinas Hipofisarias/metabolismo , Hormona de Crecimiento Humana/metabolismo , Humanos , Masculino , Invasividad Neoplásica , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Neoplasias Hipofisarias/patología , Fase S , Factores SexualesRESUMEN
A novel bioabsorbable suture anchor has been introduced for shoulder rotator cuff surgical repair made of the co-polymer 85/15 D,L lactide/glycolide. Previous clinical reports on the use of this material in anterior cruciate ligament reconstruction have described intraosseous edema at various time intervals following implantation. The purpose of this study was to analyze the implant's loss of physical properties and to correlate magnetic resonance imaging (MRI) finding with gross and histological observations at various time intervals after intraosseous implantation in the experimental animal. Six drill holes were made in the tibias of 11 dogs. The spherical implant was placed in 5 of the drill holes and the sixth was preserved as a sham control. The dogs were killed at 3, 4, 6, 9, 12, and 26 weeks for gross and microscopic inspection. Correlative MRIs were taken from the 4-, 12-, and 26-week specimens. Gross inspection showed that the overlying soft tissue healed to bone in 3 weeks. The implants were surrounded by new bone by 6 weeks. The implants maintained gross physical integrity for 6 to 12 weeks. Histologically, there was minimal inflammatory response to the degrading implant. The implant site had been completely replaced by bone at 12 weeks. Correlative MRI showed edema adjacent to the implant sites, but there was no correlative inflammation or cyst formation through the time necessary for complete absorption of the implant. Correlative MRI identified and differentiated the image of the intact and degrading implant.
Asunto(s)
Implantes Absorbibles , Huesos/patología , Huesos/cirugía , Oseointegración/fisiología , Polímeros , Suturas , Animales , Fenómenos Biomecánicos , Modelos Animales de Enfermedad , Perros , Femenino , Ácido Láctico , Imagen por Resonancia Magnética , Masculino , Ácido Poliglicólico , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Valores de Referencia , Sensibilidad y Especificidad , Tibia/patología , Tibia/cirugíaRESUMEN
The baboon response to intravenous infusion of Shiga toxin 1 (Stx-1) varied from acute renal failure, proteinuria, hyperkalemia, and melena with minimal perturbation of host inflammatory and hemostatic systems (high-dose group, 2.0 microg/kg; n = 5) to renal failure with hematuria, proteinuria, thrombocytopenia, schistocytosis, anemia, and melena (low-dose group, 0.05 to 0.2 microg/kg; n = 8). Both groups exhibited renal shutdown and died in 57 hours or less. Both groups produced urine that was positive for tumor necrosis factor and interleukin-6 although neither of these cytokines was detectable (=5 ng/ml) in the general circulation. Light and electron microscopy showed organelle disintegration and necrosis of the renal proximal tubular epithelium and of the intestinal mucosal epithelium at the tips of the microvilli, both of which were previously shown to bear Gb3 receptors. The renal distal tubular epithelium was spared. The renal proximal tubular epithelial changes were accompanied by swelling of visceral epithelial cells (podocytes) and by swelling and detachment of endothelial cells of the glomerular capillaries. In addition, all of the animals receiving low-dose Stx-1 showed microvascular fibrin deposition and thrombosis in renal glomerular and peritubular capillaries in association with a fall in hematocrit and platelet count and a rise in schistocyte count. The gastrointestinal villous tip lesions were accompanied by varying degrees of mucosal and submucosal congestion, hemorrhage, or necrosis. Electron microscopic images of cerebral cortex and cerebellum showed diffuse unraveling of myelin sheaths with occasional disintegration of neuronal cell bodies. In contrast to the gastrointestinal mucosal and renal proximal tubular epithelium, the Gb3 receptor glycolipid of the renal glomerular and neuronal tissues as determined using toxin overlay thin-layer chromatography plates was below the limit of detection (<13 pM/g wet tissue). We conclude that, depending on the status of the host and amount of toxin infused, Stx-1 can produce a variety of responses ranging from damage to cells carrying the Gb3 receptor (renal proximal tubular epithelial cells and gastrointestinal mucosa) to damage to renal glomerular tissues with microvascular thrombosis as a result of the host's inflammatory response localized to the kidney. We conclude that this thrombotic coagulopathy arises from local changes in the kidney because the appearance of host inflammatory mediators was limited to the urine. This suggests that the initial host response is localized in the kidney, and that the systemic thrombocytopenia, anemia, and schistocytosis may arise secondarily.
Asunto(s)
Toxinas Bacterianas/toxicidad , Modelos Animales de Enfermedad , Síndrome Hemolítico-Urémico/inducido químicamente , Animales , Encéfalo/patología , Relación Dosis-Respuesta a Droga , Femenino , Síndrome Hemolítico-Urémico/sangre , Síndrome Hemolítico-Urémico/orina , Interleucina-6/sangre , Interleucina-6/orina , Mucosa Intestinal/patología , Riñón/patología , Masculino , Papio , Toxinas Shiga , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/orinaRESUMEN
The purpose of this study was to determine the initial effects of Holmium:YAG laser energy on the shoulder joint capsule. A new surgical procedure to correct shoulder joint instability uses Holmium:YAG laser energy to cause "shrinkage" of joint capsular tissues. To date there has been no information concerning an intraoperative measurable end point for the application of laser energy at surgery or the resultant depth and degree of tissue alteration. Seven greyhound dogs were used in this study. Preoperative intraarticular pressures (IAP) were measured on entry and after injection of 10 ml of solution. Laser energy was applied to the cranial medial glenohumeral ligament and joint capsule of all right shoulders with arthroscopic visualization. The unoperated left shoulders served as the control group. Six weeks after surgery pressure measurements were performed on both shoulders. A "second look" arthroscopy was performed on the shoulders. After euthanasia was performed, the anterior capsular tissues were harvested from both shoulders for histologic examination. The specimens were inspected by three blinded examiners. After 6 weeks the postoperative laser-treated IAP were higher than the same joint preoperative IAP in four of six dogs for both static nondistension and 10 ml distension measurements. At this same interval the marked tissue damage of the treated capsule was easily discerned by blinded observers. On histologic evaluation the laser-treated capsule showed synovitis and pericapsular tissue reactivity. The depth of the injury was beyond the joint capsule into the pericapsular tissue. It was not possible to determine the end point of the capsular "shrinkage" operation by combined pressure/volume intraoperative measurements. There was no uniform joint capsule compliance at 6 weeks. The histologic changes were extensive in both magnitude and depth. Future studies in this animal should include decreased laser energy plus other means of monitoring the intraoperative effects of laser use.
Asunto(s)
Terapia por Láser , Articulación del Hombro/cirugía , Animales , Artroscopía , Perros , Ligamentos Articulares/patología , Presión , Articulación del Hombro/patología , Articulación del Hombro/fisiopatología , Membrana Sinovial/patologíaRESUMEN
Electromicroscopic examinations were carried out on 30 myocardial biopsies taken from 22 human donor hearts immediately after excision (prestorage) or immediately before transplantation (poststorage). All electron micrographs were independently examined by two morphologists. Eleven structures were examined in each micrograph, and each structure was scored according to the degree of injury. A good interobserver correlation was obtained in 84% of the structures scored. In the prestorage left ventricular biopsies (n = 11), approximately 20%-25% showed moderate to severe ultrastructural injury. The ultrastructural injury observed in the poststorage left ventricular biopsies (n = 15) was no different from that in the prestorage group, particularly injury to the sarcomere and mitochondria. A similar degree and pattern of injury was seen in the right ventricle (n = 4). There was no evidence that an ischemic storage period of less than 6 h increased the degree of injury seen. However, there was a higher incidence of moderate to severe injury in those hearts excised from donors initially dependent on high inotropic support.
Asunto(s)
Muerte Encefálica/patología , Trasplante de Corazón , Miocardio/ultraestructura , Donantes de Tejidos , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Microscopía Electrónica , Miocardio/patologíaRESUMEN
Comparison of perilesional cartilage, lesional repair tissue, and subchondral bone activity 6 months after application of holmium-yttrium-aluminum-garnet (Ho:YAG) laser energy to chronic (10 week) induced 10-mm full-thickness (FT) circular articular cartilage craters followed by 6 months' intermittent active motion (IAM) in a free exercise environment was investigated. The 2.1-microns wavelength was delivered in hand-controlled near-contact mode by arthroscopic surgery in a saline medium. Bilateral arthroscopy was performed on normal antebrachiocarpal, intercarpal, and metacarpophalangeal joints of six adult horses. Full-thickness craters were created in nine sites per limb on weight-bearing articular surfaces with a motorized bur. Right limb craters served as sham operated controls. Animals were killed at 10 weeks after FT crater creation (n = 2), and at 24 weeks (6 months) after laser energy application (n = 4). Histological analysis using hematoxylineosin (HE) and Safranin-O staining consisted of a modified Mankin grading of perilesional cartilage and lesional repair tissue scoring. Biochemical analysis was performed for cellularity and glycosaminoglycan (GAG) synthesis. Histological analysis showed clustering of chondrocytes or perilesional zonal cloning (PZC) in 83% of laser-treated lesions and in no control lesions. No differences were observed between treated and control lesional repair activity. Laser-treated perilesional cartilage showed a significant (P < .02) decrease in GAG synthesis. No adverse effects to distant cartilage were observed after application of laser energy regarding cell proliferation or GAG synthesis. Significance of decreased GAG synthesis in treated perilesional cartilage and perilesional zonal cloning of chondrocytes in treated cartilage is unknown. Additional study of Ho:YAG laser energy application to cartilage and subchondral bone is needed before its application in the surgical management and repair of cartilage damage.
Asunto(s)
Artroscopios , Cartílago Articular/cirugía , Endoscopios , Terapia por Láser/instrumentación , Rango del Movimiento Articular/fisiología , Soporte de Peso/fisiología , Animales , Cartílago Articular/patología , División Celular/fisiología , Glicosaminoglicanos/metabolismo , Caballos , Cicatrización de Heridas/fisiologíaRESUMEN
Heterotopic allografting of ABO-incompatible donor hearts in recipient baboons "hyperimmunized" against the incompatible A or B antigen (n = 3) was followed by hyperacute antibody-mediated vascular rejection within a mean of 19 min. The A and B epitopes against which these antibodies are directed are carbohydrates that can be synthesized. The continuous i.v. infusion of the specific synthetic A or B trisaccharide, beginning immediately pre-transplant and continued posttransplant for several days, prolonged allograft survival to a mean of 8 days (n = 2) and prevented antibody-mediated rejection, graft failure resulting from acute cellular rejection. The addition of triple pharmacologic immunosuppressive therapy (n = 4) resulted in prolongation of graft survival to a mean of > 28 days, with one heart still beating at 52 days; all grafts showed features of cellular rejection. "Accommodation" would appear to have developed in several baboons as graft function continued for periods of up to 39 days after discontinuation of carbohydrate therapy. Specific i.v. carbohydrate therapy should allow organ allografting to be performed across the ABO blood group barrier in humans. Furthermore, if the carbohydrate epitopes on the organs of discordant animals (e.g., the pig) against which human xenoreactive antibodies are directed can be confirmed, then this form of therapy might allow successful discordant organ xenotransplantation in man.
Asunto(s)
Sistema del Grupo Sanguíneo ABO/inmunología , Supervivencia de Injerto , Trasplante de Corazón/inmunología , Oligosacáridos/uso terapéutico , Trasplante Homólogo/inmunología , Animales , Azatioprina/administración & dosificación , Azatioprina/uso terapéutico , Incompatibilidad de Grupos Sanguíneos , Conformación de Carbohidratos , Secuencia de Carbohidratos , Ciclofosfamida/administración & dosificación , Ciclofosfamida/uso terapéutico , Ciclosporina/uso terapéutico , Esquema de Medicación , Rechazo de Injerto/inmunología , Supervivencia de Injerto/efectos de los fármacos , Trasplante de Corazón/fisiología , Terapia de Inmunosupresión/métodos , Infusiones Intravenosas , Metilprednisolona/administración & dosificación , Metilprednisolona/uso terapéutico , Datos de Secuencia Molecular , Oligosacáridos/administración & dosificación , Papio , Factores de Tiempo , Trasplante HeterotópicoRESUMEN
An in vivo biopsy technique was developed to harvest cylindrical osteochondral core samples (2 mm diameter x 2 mm depth) from the articular surfaces of radial carpal bones in adult horses for use in osteoarthritis drug kinetic studies. A 25 degree arthroscope was introduced into the midcarpal joint through the dorsolateral surface, and a custom-built motorized core drill was introduced through the dorsomedial surface to create the osteochondral core samples. A total of 24 core samples were sequentially harvested in vivo, and 16 at postmortem, from eight horses on four different occasions within a 96-h period. Cores ranged in weight, from 5.0 to 19.0 mg with a median of 13.25 mg, mostly due to the amount of subchondral bone present. No evidence of carpal bone fractures was observed associated with core sample sites at postmortem. No tissue distortion or thermal damage occurred to the osteochondral core samples. No detrimental effects on the tissue surrounding the biopsy sites was detected on microscopic examination. This technique offers a simple and effective procedure for obtaining multiple in vivo osteochondral core samples at various time intervals for cartilage or osteoarthritis research or analysis of clinical joint disease in the horse.
Asunto(s)
Biopsia/métodos , Carpo Animal/cirugía , Pie/cirugía , Animales , Artroscopios , Artroscopía/métodos , Artroscopía/veterinaria , Biopsia/instrumentación , Cartílago/patología , Estudios de Evaluación como Asunto , Miembro Anterior , CaballosRESUMEN
A number of studies have suggested that HIV infection can be detected in a variety of routinely fixed archival tissues using antibodies to various viral proteins. In order to study this immunocytochemical approach, paraffin sections were examined with a large panel of commercially available monoclonal antibodies against the various HIV proteins (5 antibodies to p24, 1 to p17, 1 to gp41, and 1 to gp120) using a streptavidin-biotin method. A polyclonal antibody against p24 was also tested. Formalin-fixed, paraffin-embedded HIV infected CEM E5 T cells were used as positive controls. Tissues from AIDS patients included 31 kidneys, 8 lymph nodes, 2 spleens and 3 brains. Non-AIDS tissues examined were 6 renal biopsies with focal segmental glomerulosclerosis, 5 with interstitial nephritis, 6 reactive lymph nodes, and a brain with encephalitis, all from patients not known to be at high risk for HIV infection. Additional negative controls included: 1) replacement of primary antibody with a hybridoma derived mouse monoclonal IgG1 standard, 2) omission of the primary antibody, and 3) sections of formalin-fixed paraffin-embedded CEM E5 T cells cultures not infected with HIV. Competition experiments with excess recombinant p24 protein were also performed. False positive staining with the IgG1 standard or with the antibodies to HIV proteins was frequently seen in tissues with pathologic findings (inflammation, hyalin degeneration), particularly following protein digestion. Protein digestion also had a major impact on specific staining. Digestion with proteinase K abolished specific staining for the core proteins of the virus (p17, p24) on the positive control sections.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Nefropatía Asociada a SIDA/microbiología , Proteína p24 del Núcleo del VIH/inmunología , VIH/aislamiento & purificación , Riñón/microbiología , Adhesión del Tejido , Fijación del Tejido , Anciano , Anticuerpos Monoclonales , Niño , Preescolar , Humanos , Inmunohistoquímica/métodos , Riñón/patología , Persona de Mediana Edad , Coloración y EtiquetadoRESUMEN
Although it has been suggested that cytomegalovirus (CMV) infection of the kidney might facilitate the development of human immunodeficiency virus-associated nephropathy (HIVAN) or other morphologic renal changes in patients with AIDS, no systematic study has been performed on kidneys from AIDS patients. We examined 75 autopsy kidneys, two renal biopsy specimens, and a nephrectomy specimen from 78 HIV-infected patients (five with HIVAN) for the presence of CMV. Immunocytochemistry (ICC) utilizing a monoclonal antibody against the late antigen of CMV and in situ hybridization (ISH) with a biotinylated DNA probe for CMV sequences were used. The detection system for both ICC and ISH was streptavidin-conjugated alkaline phosphatase with Fast Red TR chromogen. CMV was detected in only 10 of the 78 kidneys examined (12.8%): eight by both methods, one by ISH only, and another by ICC only. All 10 positive kidneys were obtained from autopsies of patients with AIDS. The average number of positive cells (in approximately 15 x 10 mm sections) was 22 with ICC and 10 with ISH. Glomerular intracapillary cells (possibly endothelial cells) were the most commonly stained, followed by positive cells in the interstitium and peritubular capillaries. Relatively few tubular epithelial cells were stained. The majority of positive cells by either ICC or ISH did not show nuclear or cytoplasmic inclusions; however, only two of the 10 positive kidneys did not contain cells with typical Cowdry type-A intranuclear CMV inclusions. The most frequent pathologic finding in the kidneys positive for CMV by either ICC or ISH was acute tubular necrosis (in six of 10, 60%).(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Nefropatía Asociada a SIDA/microbiología , Síndrome de Inmunodeficiencia Adquirida/complicaciones , Infecciones por Citomegalovirus/microbiología , Citomegalovirus/aislamiento & purificación , Nefropatía Asociada a SIDA/patología , Infecciones por Citomegalovirus/patología , Sondas de ADN , Humanos , Inmunohistoquímica , Hibridación de Ácido NucleicoRESUMEN
The binding sites of five monoclonal antibodies (MAb) developed against rat Pneumocystis carinii were examined at the ultrastructural level by using a post-embedding labeling method. Although all five MAb reacted with the pellicle of P. carinii, they were divided into two groups by localization of binding sites. The MAb 168.2.1, 174.2.1, and 215.2.1 reacted mainly with the electron-dense outer layer, whereas MAb 227.1.1 and 228.1.1 labeled both the outer dense layer and the middle lucent layer. With in the first group of MAb, no significant differences were observed in the reactivity patterns seen with the different stages of P. carinii. In the second group, however, the intensity of labeling of the electron-dense layer was higher in the precyst, cyst, and ruptured cyst stages than in the trophozoite stage. These latter results indicate that there may be an increase in antigen accumulation during development from the trophozoite to the cyst stages, or that antigens may be modified the development.
Asunto(s)
Anticuerpos Antifúngicos/inmunología , Anticuerpos Monoclonales/inmunología , Antígenos Fúngicos/inmunología , Epítopos/inmunología , Pneumocystis/inmunología , Animales , Proteínas Bacterianas , Sitios de Unión de Anticuerpos , Oro , Pulmón/parasitología , Ratas , EstreptavidinaRESUMEN
The relative sensitivities of the indirect immunobead test, the indirect flo cytometric immunofluorescence assay, and an indirect radiolabeled antiglobulin assay were compared. Eighteen immunobead test positive sera and 18 negative sera were used as the standard for the other two assays. Of the 18 positive sera, 14 (77%) and 5 (27%) were positive in the immunofluorescence assay and the radiolabeled antiglobulin assay, respectively. Four (22%) of the low titer immunobead test positive sera were negative by both the immunofluorescence assay and the radiolabeled antiglobulin assay. However, there was a significant positive correlation between the results of the immunofluorescence assay and the radiolabeled antiglobulin assay (r = 0.73) and between the results of the radiolabeled antiglobulin assay and the titer of the immunobead test (r = 0.82). The use of an unselected sperm population in the radiolabeled antiglobulin assay and the classical indirect immunofluorescence method using methanol-fixed sperm gave false-positive results in the radiolabeled antiglobulin assay and the immunofluorescence assay. These results suggested that immunoglobulin G antisperm antibody positive sera may be reactive both to sperm surface and internalized sperm antigens.
Asunto(s)
Autoanticuerpos/análisis , Inmunoglobulina G/análisis , Espermatozoides/inmunología , Citometría de Flujo/métodos , Fluoresceína-5-Isotiocianato , Fluoresceínas , Técnica del Anticuerpo Fluorescente , Colorantes Fluorescentes , Humanos , Inmunoensayo/métodos , Radioisótopos de Yodo , Lupus Eritematoso Sistémico/sangre , Lupus Eritematoso Sistémico/inmunología , Masculino , Técnica de Dilución de Radioisótopos , TiocianatosRESUMEN
To investigate the role of C in the pathogenesis of antisperm antibody (ASA)-mediated infertility, we evaluated the binding and biologic effects of antisperm IgG and autologous C on human sperm. A flow cytometric assay using motile sperm as a target for IgG ASA+ (n = 30) and ASA- (n = 5) sera was developed for the concomitant detection of sperm-bound IgG and the initial (C3d) and terminal (C5b-9) C components on the surface of human sperm. Of the 30 IgG ASA+ sera evaluated by flow cytometry, 15 (50%) and 22 (73.3%) sera were also positive for sperm-bound C3d and C5b-9, respectively. Monomeric IgG purified from C-fixing ASA+ serum was able to bind to sperm and induced deposition of C3 on the sperm surface in the presence of human C. Incubation of motile sperm with C-fixing immune sera resulted in a significant loss (43 to 87%) of motility associated with characteristic C5b-9-induced alterations in sperm morphology leading ultimately to sperm lysis. When motile sperm were cocultured with purified polymorphonuclear leukocytes (PMN) in the presence of C-fixing immune sera, the binding of sperm heads to the PMN resulted in the formation of sperm rosettes, whereas non C-fixing or control sera had no such effect. Transmission electron microscopy of thin sections of the rosettes revealed ingestion of the sperm by the human PMN. These data suggested that 1) antibody bound to sperm is capable of activating autologous C by the classical pathway; 2) binding of both IgG and C proteins initiates C3-mediated sperm binding to PMN and sperm inactivation by deposition of membrane attack complex (MC5b-9) of C; and 3) concomitant detection of sperm-bound IgG, C3d, and C5b-9 may serve as an indicator of C-fixing cytotoxic ASA in the sera of infertile couples.
Asunto(s)
Autoanticuerpos/fisiología , Proteínas del Sistema Complemento/fisiología , Isoanticuerpos/fisiología , Espermatozoides/inmunología , Activación de Complemento , Complemento C3/metabolismo , Complemento C3/fisiología , Complejo de Ataque a Membrana del Sistema Complemento/metabolismo , Complejo de Ataque a Membrana del Sistema Complemento/fisiología , Citotoxicidad Inmunológica , Femenino , Citometría de Flujo , Humanos , Inmunoglobulina G/metabolismo , Masculino , Neutrófilos/metabolismo , Fagocitosis , Unión Proteica , Espermatozoides/patologíaRESUMEN
The acrosomal status of human sperm was assessed by the specific binding of Pisum sativum lectin to the acrosomal matrix. Immunoglobulin G (IgG) fractions of plasmas that were positive for IgG antisperm antibodies inhibited acrosomal loss, initiated acrosomal loss, or had no effect on acrosomal loss. Two of five sperm samples associated in vitro with only IgG, zero of one sample associated with only sperm-associated immunoglobulin A (IgA), and six of eight samples associated with both IgA and IgG underwent acrosomal loss prior to exposure to calcium ionophore. Two sperm samples associated with IgG or IgA or both were inhibited from undergoing acrosome loss after exposure to calcium ionophore. None of the seven antibody-negative sperm samples underwent an increased spontaneous acrosomal loss or were inhibited from undergoing acrosomal loss after exposure to calcium ionophore.
Asunto(s)
Acrosoma/inmunología , Autoanticuerpos/inmunología , Lectinas de Plantas , Espermatozoides/inmunología , Acrosoma/fisiología , Acrosoma/ultraestructura , Membrana Celular/fisiología , Membrana Celular/ultraestructura , Humanos , Inmunoglobulina G/inmunología , Técnicas In Vitro , Lectinas , Masculino , Capacitación Espermática , Espermatozoides/fisiología , Espermatozoides/ultraestructuraRESUMEN
IL-2 receptors on T cells exist in at least three forms which differ in their ligand-binding affinity. The low-affinity IL-2 receptor (IL-2R) consists of the 55-kDa Tac protein (p55 alpha), the intermediate-affinity site corresponds to the 70-kDa molecule (p70 beta), and the high-affinity IL-2R consists of a noncovalent heterodimeric structure involving both p55 alpha and p70 beta. We studied 24 B cell lines (8 EBV-negative and 16 EBV-positive) for IL-2R expression in the presence or absence of the tumor promoter, teleocidin. 125I-IL-2 radioreceptor binding assays and crosslinking studies demonstrated the sole expression of p55 alpha in EBV-negative cell lines only, whereas p55 alpha present in EBV-positive cell lines was always associated with p70 beta to construct high-affinity IL-2R. p70 beta was not detected in any of the EBV-negative cell lines, but was expressed on most of the EBV-positive cell lines (13 of 16). Our data also indicate that the expression of p55 alpha and p70 beta by radiolabeling correlates with their expression in flow cytometry, and that a large excess of p55 alpha is required to construct high-affinity IL-2R. Coexpression of p55 alpha and p70 beta on human B cells contributed to constructing high-affinity IL-2R hybrid complex as shown by (i) rapid association rate contributed by p55 alpha and slow dissociation rate by p70 beta; (ii) teleocidin's ability to induce p55 alpha on cell lines which express p70 beta only, resulting in appearance of high-affinity IL-2R; (iii) blocking p55 alpha by anti-Tac mAb in cell lines which constitutively express high-affinity IL-2R eliminated both high- and low-affinity components. The existence of low, intermediate, and high IL-2R on human B cells bears important future implications for understanding the mechanism of IL-2 signaling and the role of IL-2 in B cell activation, proliferation, and differentiation.
Asunto(s)
Linfocitos B/metabolismo , Linfoma de Burkitt/inmunología , Linfoma/inmunología , Receptores de Interleucina-2/biosíntesis , Unión Competitiva , Línea Celular , Línea Celular Transformada , Reactivos de Enlaces Cruzados , Citometría de Flujo , Humanos , Interleucina-2/metabolismo , Radioisótopos de Yodo , Cinética , Células Tumorales CultivadasRESUMEN
Two-color fluorescence-activated cell sorting of antisperm antibody-positive sperm was used to detect simultaneously the presence of immunoglobulin (Ig)A and IgG antisperm antibodies associated in vivo on a man's sperm. Sperm positive for sperm-associated Ig were analyzed using phycoerythrin-conjugated antihuman IgA and fluorescein isothiocyanate-conjugated antihuman IgG; up to 87% of the same spermatozoa were stained with both labels. Sperm positive for only one of the antisperm antibody isotypes stained up to 90% of a man's sperm with only one fluorochrome. Immunocytochemistry studies revealed similar patterns of sperm binding for sperm-associated IgG and IgA. These results suggest that the sperm antigenic determinants reacting with antisperm IgA and IgG are present on the same sperm population at similar locations on the sperm surface.
Asunto(s)
Citometría de Flujo , Inmunoglobulina A/análisis , Inmunoglobulina G/análisis , Espermatozoides/inmunología , Separación Celular , Epítopos/análisis , Fluoresceína-5-Isotiocianato , Fluoresceínas , Técnica del Anticuerpo Fluorescente , Colorantes Fluorescentes , Humanos , Técnicas para Inmunoenzimas , Infertilidad Masculina/inmunología , Radioisótopos de Yodo , Masculino , Ficoeritrina , TiocianatosRESUMEN
Brain death is associated with neuroendocrine changes, in particular with a significant reduction of plasma-free triiodothyronine (T3) that results in impaired aerobic metabolism. Myocardial energy stores are reduced and tissue lactate increased. Cardiac function deteriorates. Similar metabolic changes are seen in patients undergoing open-heart surgery on cardiopulmonary bypass, including those undergoing heart transplantation. Therapy with T3 leads to a reversal of these metabolic changes, resulting in improved cardiac function. One hundred and sixteen consecutive potential donors have been so treated, as have 70 of the recipients. Immediate posttransplant cardiac function was good in all but 3, and these hearts recovered to normal within a maximum of 24 hr of mechanical support. In 2 small randomized trials in patients undergoing myocardial revascularization on cardiopulmonary bypass, postoperative T3 therapy was associated with a reduced need for inotropic support and diuretic therapy in the first study and improved cardiac output in the second study.
Asunto(s)
Trasplante de Corazón , Triyodotironina/uso terapéutico , Adenosina Trifosfato/metabolismo , Animales , Gasto Cardíaco , Metabolismo Energético , Humanos , Microscopía Electrónica , Contracción Miocárdica , Miocardio/metabolismo , Miocardio/ultraestructura , Papio , Fosfocreatina/metabolismo , PorcinosRESUMEN
It has been hypothesized that some fixatives and conditions of slide preparation expose internal sperm antigens and thus are not suitable for demonstrating surface-specific antigens by immunocytochemical assays. This study examined the ability of five fixatives (glutaraldehyde, acetone, methanol, paraformaldehyde, and periodate-lysine-paraformaldehyde [PLP]) and two conditions of slide preparation (air-drying or maintaining sperm in a liquid phase) to maintain the integrity of human spermatozoal membranes at the ultrastructural level as monitored by transmission electron microscopy. Regardless of the fixative employed, air-drying was detrimental to plasma and acrosomal membrane integrity. Acetone and methanol completely disrupted the plasma and acrosomal membranes over the entire sperm surface whether air-drying or liquid phase conditions were employed. Fixation with glutaraldehyde and paraformaldehyde (to a lesser degree) maintained the morphologic integrity of acrosomal and plasma membranes provided the sperm were maintained in a liquid phase. However, glutaraldehyde and paraformaldehyde fixation increased the postfixation binding of immunoglobulins to the sperm surface. We concluded that immunocytochemistry at the light microscopy level may imply erroneous interpretations regarding antigen/antibody interactions on the sperm plasma membrane surface unless care is taken to verify that the antibodies of interest are binding to the antigenically intact plasma or acrosomal membrane.