ABSTRACT
INTRODUCTION: Tumours in the pineal region are located at a meeting point of several neurovascular structures that are difficult to reach surgically and for which the possibility of resection is limited; as a result the management of these lesions usually requires associated adjunctive treatment with radiotherapy and/or chemotherapy. PATIENTS AND METHODS: This study is a retrospective analysis of the epidemiological, clinical, neuroimaging and pathological characteristics of 23 patients with tumours in the pineal region who were treated between the years 1997 and 2010 in the Hospital Infantil Niño Jesús. The factors involved in the prognosis of this cohort following surgical or adjunctive treatment are also discussed. RESULTS: Subjects included in the study were 6 girls and 17 boys with ages ranging from 4 months to 18 years. It was found that the initial symptoms in 95% of the patients were signs of acute or subacute hydrocephalus, which required the placement of a ventriculoperitoneal shunt (82%). A histological sample of the tumour tissue was collected in all cases. Biopsy samples were taken in the case of five patients and 18 underwent surgery involving a craniotomy. Germinoma (eight cases) and mature teratoma (one case) were the tumours with the longest survival times; non-germinomatous tumours (three cases), those of the pineal parenchyma (four cases) and gliomas (five cases) presented the highest rates of recurrence and a poorer prognosis. CONCLUSIONS: The study of tumour markers can be used to guide the diagnosis of certain tumours of the pineal region. At present, the recommended procedure involves taking a histological sample of the tumour in order to establish an accurate diagnosis and a specific oncological treatment.
Subject(s)
Brain Neoplasms/diagnosis , Brain Neoplasms/pathology , Pineal Gland/pathology , Adolescent , Biomarkers, Tumor/analysis , Biopsy , Brain Neoplasms/epidemiology , Brain Neoplasms/surgery , Child , Child, Preschool , Female , Humans , Infant , Male , Pineal Gland/surgery , Prognosis , Retrospective StudiesABSTRACT
INTRODUCTION AND AIM: Radiosurgery is among the treatment options for patients with vestibular schwannoma. We present the experience in our institution in the treatment of this disease with this technique. PATIENTS AND METHODS: A retrospective study was made including 20 patients (11 women and 9 men; median age: 55.15 years-old) with vestibular schwannoma who received linear accelerator radiosurgery treatment since April 2005 until December 2008. Follow-up period was between 12 and 42 months, considering clinical examination of cranial nerves VII (House-Brackmann scale) and VIII (Gardner-Robertson scale) as well as radiological findings (considering tumor volume). For statistical analysis, the Fisher's exact test and logistic regression test were used. RESULTS: Certain worsening of hearing function was present in 25% of the patients. Five patients had large tumors at the moment of the treatment (equal or larger than 3.5 cm3), from which four deteriorated from headache, unsteady gait, dizziness/vertigo, facial numbness and tinnitus, with statistical significance (p < 0.05). From the first year of treatment on, there was a tumor volume decrease tendency, with no tumor growth in the medium/long term follow-up, achieving a local control rate of 100%. CONCLUSIONS: Radiosurgery has become an alternative in the treatment of patients with vestibular schwannoma of appropriate size, with high safety level, using low radiation doses, low rate of complications and good tumor control rate in the medium term follow-up.
Subject(s)
Neuroma, Acoustic/surgery , Radiosurgery/methods , Adult , Aged , Facial Nerve/physiology , Facial Nerve/physiopathology , Facial Nerve/surgery , Female , Hearing/physiology , Hearing Tests , Humans , Male , Middle Aged , Neuroma, Acoustic/pathology , Retrospective Studies , Treatment Outcome , Vestibulocochlear Nerve/physiology , Vestibulocochlear Nerve/physiopathology , Vestibulocochlear Nerve/surgeryABSTRACT
INTRODUCTION AND AIMS: One of the therapeutic options for chronic adult hydrocephalus that has become widely used in our service is the lumboperitoneal shunt with low-pressure Spetzler catheter and in an outpatient regimen. We report on the first 30 patients treated in this way with a follow-up of between one and five years. PATIENTS AND METHODS: Diagnosis was reached after studying the patient history and a clinical examination; Hakim and Adams' triad was found to be a primary and highly predictive factor, together with flow magnetic resonance imaging and the use of the ambulatory tap test. Patients who responded to the latter were submitted to placement of a shunt in a short operation performed with local anaesthetic and sedation. An evaluation of the three symptoms was carried out before and after the intervention according to a mixed scale (Rankin-Stein and Langfitt-Vall d'Hebron) and graphic tests based on the minimental test. RESULTS: At three months, 21 patients (70%) had improved and 14 of them (65%) maintained this improvement at three years; eight of these have been monitored for four and five years. Five patients died due to intercurrent illnesses. CONCLUSIONS: After comparing the complications that occurred with other case mixes involving both lumboperitoneal and ventriculoperitoneal shunts, we discuss the usefulness of this method (which is preferred by patients and relatives) in comparison to ventriculoperitoneal shunts, where the complications are more severe because they invade the brain and due to the need for general anaesthesia and longer hospitalisation. In addition, the method is more economical than the alternatives.
Subject(s)
Ambulatory Surgical Procedures , Hydrocephalus/surgery , Ventriculoperitoneal Shunt/methods , Aged , Aged, 80 and over , Chronic Disease , Female , Follow-Up Studies , Humans , Lumbosacral Region , Male , Middle Aged , PeritoneumABSTRACT
Introducción y objetivo. Dentro de las opciones terapéuticas de la hidrocefalia crónica del adulto, ha ido imponiéndoseen nuestro servicio la derivación lumboperitoneal con catéter de baja presión de Spetzler y en régimen ambulatorio.Presentamos los primeros 30 pacientes así tratados con un seguimiento de entre uno y cinco años. Pacientes y métodos. Realizamosel diagnóstico mediante la anamnesis y exploración clínica, constatando la tríada de Hakim y Adams como factor primordialy de gran valor predictivo, así como la resonancia magnética de flujo y el uso de la punción lumbar de prueba (taptest) ambulatoria. Los pacientes que respondieron a ésta fueron sometidos al implante del shunt en una breve intervención conanestesia local y sedación. Se realizó antes y después una valoración de los tres síntomas según una escala mixta (Rankin-Stein y Langfitt-Vall dHebron) y pruebas gráficas basadas en el test minimental. Resultados. A los tres meses habían mejorado21 pacientes (70%) y mantuvieron la mejoría a los tres años 14 pacientes (65%); ocho de éstos han sido controlados cuatroy cinco años. Cinco pacientes fallecieron por enfermedades intercurrentes. Conclusiones. Tras compararse las complicacioneshabidas con otras casuísticas tanto de derivación lumboperitoneal como de derivación ventriculoperitoneal, se comentala utilidad del método, preferido por los pacientes y familiares, frente al de derivación ventriculoperitoneal, donde las complicacionestienen mayor gravedad al invadir el cerebro y ante la necesidad de anestesia general e ingreso más prolongado.El método, además, es más económico que los alternativos(AU)
Introduction and aims. One of the therapeutic options for chronic adult hydrocephalus that has become widely usedin our service is the lumboperitoneal shunt with low-pressure Spetzler catheter and in an outpatient regimen. We report on thefirst 30 patients treated in this way with a follow-up of between one and five years. Patients and methods. Diagnosis wasreached after studying the patient history and a clinical examination; Hakim and Adams triad was found to be a primary andhighly predictive factor, together with flow magnetic resonance imaging and the use of the ambulatory tap test. Patients whoresponded to the latter were submitted to placement of a shunt in a short operation performed with local anaesthetic andsedation. An evaluation of the three symptoms was carried out before and after the intervention according to a mixed scale(Rankin-Stein and Langfitt-Vall dHebron) and graphic tests based on the minimental test. Results. At three months, 21patients (70%) had improved and 14 of them (65%) maintained this improvement at three years; eight of these have beenmonitored for four and five years. Five patients died due to intercurrent illnesses. Conclusions. After comparing thecomplications that occurred with other case mixes involving both lumboperitoneal and ventriculoperitoneal shunts, we discussthe usefulness of this method (which is preferred by patients and relatives) in comparison to ventriculoperitoneal shunts, wherethe complications are more severe because they invade the brain and due to the need for general anaesthesia and longerhospitalisation. In addition, the method is more economical than the alternatives(AU)
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Hydrocephalus/diagnosis , Hydrocephalus/surgery , Ambulatory Surgical Procedures/methods , Dementia/complications , Dementia/diagnosis , Anesthesia, Local/methods , Hydrocephalus/physiopathology , Hydrocephalus , Medical History Taking/methodsABSTRACT
Skull defects and even meningeal defects are responsible for the majority of pneumocephalus cases. Sometimes, several factors can produce intracranial gas under pressure (tension pneumocephalus) with severe neurological impairment. We present a case of a 66 year old woman with a double ventriculo-peritoneal shunt that was admitted to the emergency service with an intracranial hypertension syndrome. A scalp wound was found on the physical examination and a brain CT showed a tension pneumocephalus. The scalp wound was just located on the border of a cranioplasty made after surgical removal of a parasagital meningioma eight years ago. Evacuation of pneumocephalus, reparation of cranial and meningeal defects and modification of factors contributing to the tension pneumocephalus (ventricular-peritoneal shunts programmed to low pressure) were performed. When we found a patient with a tension pneumocephalus we must think not only about a skull or meningeal defect but also look for other elements that produce gas inside skull under pressure (shunts, cerebrospinal fluid leak between others). Therefore, therapeutic approach has three parts: pneumocephalus drainage, to find and repair entrance of gas and to modify factors that turn pneumocephalus in a tension pneumocephalus.
Subject(s)
Head Injuries, Closed/complications , Pneumocephalus/etiology , Scalp/injuries , Ventriculoperitoneal Shunt/adverse effects , Aged , Female , Head Injuries, Closed/pathology , HumansABSTRACT
El neumoencéfalo se produce la mayoría de lasveces por una solución de continuidad en el cráneo eincluso en las meninges. En ocasiones, ciertos factorespueden hacer que éste adopte las características deun neumoencéfalo a tensión provocando una clínicaneurológica severa. Presentamos el caso de una pacientede 66 años portadora de una doble válvula de derivaciónventrículo-peritoneal que acude a Urgencias con uncuadro de hipertensión intracraneal y que tras la exploraciónfísica y la tomografía computarizada se detectauna herida en cuero cabelludo y un neumoencéfalo atensión. Este defecto en piel se hallaba justo en la zonadel borde de una plastia craneal colocada tras la resecciónde un meningoma parasagital 8 años antes. Se realizódrenaje, reparación de la solución de continuidady modificación de los factores que agravaban el cuadrodel neumoencéfalo (la presencia de unas válvulas dederivación con presiones de salida muy bajas).La presencia de un neumoencéfalo a tensión debehacernos pensar en encontrar no sólo el punto deacceso del aire al interior del cráneo sino también lascausas que han favorecido que el neumoencéfalo adoptecaracterísticas de alta presión (sistemas de derivacióno fístulas de LCR entre otros). De esta forma la orientaciónterapéutica adecuada tiene que ir destinada a lamodificación de estos factores agravantes, además dehacia el drenaje del neumoencéfalo y cierre del defectocraneal (AU)
Skull defects and even meningeal defects are responsiblefor the majority of pneumocephalus cases.Sometimes, several factors can produce intracranialgas under pressure (tension pneumocephalus) withsevere neurological impairment. We present a case of a66 year old woman with a double ventriculo-peritonealshunt that was admitted to the emergency service withan intracranial hypertension syndrome. A scalp woundwas found on the physical examination and a brain CTshowed a tension pneumocephalus. The scalp woundwas just located on the border of a cranioplasty madeafter surgical removal of a parasagital meningiomaeight years ago. Evacuation of pneumocephalus, reparationof cranial and meningeal defects and modificationof factors contributing to the tension pneumocephalus(ventricular-peritoneal shunts programmed to lowpressure) were performed.When we found a patient with a tension pneumocephaluswe must think not only about a skull or meningealdefect but also look for other elements that producegas inside skull under pressure (shunts, cerebrospinalfluid leak between others). Therefore, therapeuticapproach has three parts: pneumocephalus drainage,to find and repair entrance of gas and to modify factorsthat turn pneumocephalus in a tension pneumocephalus (AU)
Subject(s)
Humans , Female , Middle Aged , Ventriculoperitoneal Shunt/adverse effects , Wounds and Injuries , Pneumocephalus/diagnosis , Pneumocephalus/etiologyABSTRACT
Pretendemos evaluar la utilidad de la detección de antígenode Streptococcus pneumoniae en orina en el diagnóstico de laneumonía extrahospitalaria en niños que necesitaron ingresohospitalarioMATERIAL Y MÉTODOSEstudio prospectivo durante 15 meses de 61 niños ingresadospor neumonía extrahospitalaria y 21 niños sanos como control.La detección del antígeno se realizó mediante el sistemaBinax Now previa concentración de la orinaRESULTADOSLa técnica mostró una sensibilidad del 100%, una especificidaddel 21.4% El 78.8% de los niños con neumonía presentanantígeno en orina, aunque también se encontraba en el 47%de niños sanos (p=0.005). CONCLUSIONESEstá técnica no es útil en el diagnóstico de este proceso por suescasa especificidad. Sin embargo, la dificultad de establecer unpatrón diagnóstico de la neumonía neumocócica no bacteriémicadificulta la correcta evaluación de esta técnica y otros datossugieren que los datos de especificidad pueden ser superiores
Our aim is to assess the usefulness of the detection ofStreptococcus pneumoniae antigen in urine in the diagnosis ofextrahospital pneumonia in children who require admission tohospitalMATERIAL AND METHODSProspective study over a period of 15 months of 61 childrenadmitted to hospital with extrahospital pneumonia and 21healthy children as controls. The antigen was detected usingthe Binax Now system after concentrating the urineRESULTSThe technique was seen to have a sensitivity of 100%, aspecificity of 21.4%. The antigen in urine was present in 78.8%of the children with pneumonia, and also in 47% of the healthychildren (p=0.005). This technique is not useful because it has a low specificity,but the difficulty in establishing diagnostic guidelines for nonbacteraemiapneumococcus pneumonia makes it difficult toassess this technique properly, although other data indicatethat it may have greater specificity
Subject(s)
Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Humans , Streptococcus pneumoniae/isolation & purification , Pneumococcal Infections/urine , Pneumonia/diagnosis , Antigens/isolation & purification , Hospitalization , Community-Acquired Infections/diagnosis , Prospective StudiesABSTRACT
The present study contributes to clarify the mechanism underlying the high efficacy of hepatocyte gene transfer mediated by hydrodynamic injection. Gene transfer experiments were performed employing the hAAT gene, and the efficacy and differential identification in mouse plasma of human transgene versus mouse gene was assessed by ELISA and proteomic procedures, respectively. By applying different experimental strategies such as cumulative dose-response efficacy, hemodynamic changes reflected by venous pressures, intravital microscopy, and morphological changes established by transmission electron microscopy, we found that: (a) cumulative multiple doses of transgene by hydrodynamic injection are efficient and well tolerated, resulting in therapeutic plasma levels of hAAT; (b) hydrodynamic injection mediates a transient inversion of intrahepatic blood flow, with circulatory stasis for a few minutes mainly in pericentral vein sinusoids; (c) transmission electron microscopy shows hydrodynamic injection to promote massive megafluid endocytic vesicles among hepatocytes around the central vein but not in hepatocytes around the periportal vein. We suggest that the mechanism of hydrodynamic liver gene transfer involves transient inversion of intrahepatic flow, sinusoidal blood stasis, and massive fluid endocytic vesicles in pericentral vein hepatocytes.
Subject(s)
Gene Transfer Techniques , Hepatocytes/ultrastructure , Liver Circulation , Animals , Cytoplasmic Vesicles/ultrastructure , Endocytosis , Enzyme-Linked Immunosorbent Assay/methods , Genetic Vectors/administration & dosage , Humans , Mice , Mice, Inbred C57BL , Microscopy, Electron , Molecular Sequence Data , Portal Vein/physiology , Vena Cava, Inferior/physiology , Venous Pressure , alpha 1-Antitrypsin/genetics , alpha 1-Antitrypsin/metabolismABSTRACT
DNA complexes formed with nonviral vectors such as polyethylenimine (PEI) or 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) are widely used in gene therapy. These complexes prevent the interaction of DNA with the fluorescent probes usually employed to quantify DNA. We thus studied the procedures for DNA quantification from DNA complexes as well as their stability in the presence of DNase or mouse, rat and human sera. Release of the DNA from its complexes was accomplished by increasing the pH of the medium (from 7.3 to 13.4) or by adding heparin. The stability against degradation was tested in vitro, by incubating the complexes at 37 degrees C in the presence of DNase I and sera from the three species. Both high pH and heparin were able to release DNA from its complexes. Naked DNA formed aggregates with serum proteins that delayed electrophoresis migration, and this effect was reversed in the presence of heparin. However, these aggregates did not protect DNA from digestion by serum DNase, and the DNA digesting ability of serum was: mouse>rat>human. The DNA from the complexes was resistant to degradation by DNase I, although a low proportion of DNA from the complexes was partially digested, as determined by electrophoresis. In contrast, PEI-DNA and DOTAP-DNA complexes were stable in the presence of all sera. Heparin and high pH release DNA from its complexes. The order of DNA degradation is: mouse>rat>human, but DOTAP and PEI avoid degradation of DNA by serum compounds.
Subject(s)
DNA/administration & dosage , Fatty Acids, Monounsaturated/administration & dosage , Heparin/pharmacology , Polyethyleneimine/administration & dosage , Quaternary Ammonium Compounds/administration & dosage , DNA/chemistry , Deoxyribonuclease I/pharmacology , Drug Stability , Electrophoresis, Agar Gel , Hydrogen-Ion Concentration , Microscopy, ElectronABSTRACT
The growth of new blood vessels is an essential condition for the development of tumors with a diameter greater than 1-2 mm and also for their metastatic dissemination. RNasin, the placental ribonuclease inhibitor, is known to have antiangiogenic activity through the inhibition of angiogenin and basic fibroblast growth factor. Nevertheless, the administration of the recombinant form of a protein poses several limitations; as a result, we have studied the antitumor effect of RNasin in a murine gene therapy model. RNasin cDNA was subcloned into the pcDNA3 expression vector, and the resulting recombinant plasmid was used to transfect the B16 murine melanoma cell line. An RNasin inverted construction was used as control. Mice intravenously injected with clones expressing RNasin showed a significant inhibition of tumor metastatic progression with respect to control groups (P<.001) and survived longer (P<.001). Tissue sections from RNasin-expressing cell tumors showed a lower number of blood vessels when compared to tissue sections from mice lungs that had been inoculated with control cell lines. The results of these experiments show that the genetic modification of tumor cells with RNasin cDNA yields a significant antitumor effect, and suggest that this effect is at least partially the result of angiogenesis inhibition.
Subject(s)
Angiogenesis Inhibitors/genetics , Enzyme Inhibitors , Genetic Therapy/methods , Lung Neoplasms/therapy , Melanoma, Experimental/therapy , Neovascularization, Pathologic/therapy , Placental Hormones/genetics , Animals , Cell Division , DNA Primers/chemistry , Gene Expression , Genetic Vectors , Humans , Immunoenzyme Techniques , Lung Neoplasms/blood supply , Lung Neoplasms/genetics , Melanoma, Experimental/blood supply , Melanoma, Experimental/genetics , Mice , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Ribonucleases/antagonists & inhibitors , Transcription, Genetic , Transfection , Tumor Cells, CulturedABSTRACT
We studied 7 samples of lateral retinaculae excised at the time of surgical realignments. They were obtained from patients with isolated symptomatic patellofemoral malalignment resistant to conservative treatment and were evaluated with immunohistochemistry and immunoblotting. We found that neural growth factor is higher in patients with pain than in those with instability as the main symptom. Neural growth factor is related to neural proliferation in vessels and perivascular tissue and to the release of neuroceptive transmitters, such as substance P. We postulate that both mechanisms are involved in the pathogenesis of pain in isolated symptomatic patellofemoral malalignment.
Subject(s)
Femur/pathology , Joint Instability/pathology , Knee Joint/pathology , Nerve Growth Factors/analysis , Pain/pathology , Patella/pathology , Adolescent , Adult , Female , Femur/chemistry , Femur/surgery , Gene Expression Regulation , Humans , Immunoblotting , Immunohistochemistry , Joint Instability/etiology , Joint Instability/metabolism , Knee Joint/chemistry , Knee Joint/surgery , Pain/etiology , Pain/metabolism , Patella/chemistry , Patella/surgeryABSTRACT
In the present work we set out to apply pharmacodynamic concepts derived from dose-response curves (Potency and Efficacy) to characterize the gene transfer efficiency of a vector:DNA complex. We employed two widely used vectors, the cationic lipid DOTAP (N,N, N-trimethyl 1-2-3-bis (1-oxo-9-octa-decenyl)oxy-(Z, Z)-1-propanaminium methyl sulfate) and the cationic polymer PEI (polyethylenimine, 800 kDa) to transfect several constructions of the green fluorescent protein cDNA. The analysis of dose-response curves indicated that in all cases the goodness-of-fit was > 0.99. Potency is a measure that provides information on gene activity per amount of DNA. Efficacy is a measure of maximum gene expression achievable using a specific vector:DNA complex, and depends on both the intrinsic efficacy of the gene (evaluated using different vectors to transfer the same gene construct) and on vector efficacy in DNA delivery (evaluated using a single vector to deliver different gene constructs). The results suggest that Potency and Efficacy are objective parameters for describing and comparing the goodness of vectors, as well as the intrinsic efficacy of a given gene construct. Furthermore, they are useful tools that may contribute to a better understanding of the mechanistic gene transfer process of each vector.
Subject(s)
DNA/genetics , Gene Transfer Techniques , Genetic Vectors , Animals , Anti-Bacterial Agents/pharmacology , Dose-Response Relationship, Drug , Fatty Acids, Monounsaturated/administration & dosage , Gentamicins/pharmacology , HeLa Cells , Humans , Mice , Plasmids/genetics , Quaternary Ammonium Compounds/administration & dosage , Tumor Cells, CulturedABSTRACT
The aim of this work was to investigate the influence of endothelin on myocardial ischemia and reperfusion in anaesthetized dogs. Animals were submitted to left thoracotomy and 120 min of left anterior descending coronary occlusion, followed by 180 min of reperfusion. Arterial blood pressure and electrocardiogram (ECG) were recorded in order to analyze heart rate (HR)-pressure product and production of ectopic beats. Infarcted areas were identified by a macroscopic staining method and infarct size was expressed as percentage of risk zone. To inhibit the effects of endothelin in a group of animals, we administered intravenously an endothelin synthesis inhibitor (phosphoramidon) and in another group, an endothelin-1 A receptor blocker (BQ-123). Phosphoramidon decreased the HR-pressure product during reperfusion period, and both, phosphoramidon and BQ-123 decreased infarct size by 40% and the number of ventricular ectopic beats by 88% and 68%, respectively, as compared to the saline treated dogs. In conclusion, endothelin seems to play a deleterious role on the myocardium submitted to ischemia and reperfusion.
Subject(s)
Antihypertensive Agents/therapeutic use , Coronary Disease/drug therapy , Glycopeptides/therapeutic use , Myocardial Infarction/drug therapy , Myocardial Reperfusion , Peptides, Cyclic/therapeutic use , Ventricular Premature Complexes/drug therapy , Animals , Antihypertensive Agents/pharmacology , Blood Pressure/drug effects , Coronary Disease/physiopathology , Dogs , Drug Therapy, Combination , Endothelin Receptor Antagonists , Endothelin-1/antagonists & inhibitors , Endothelin-1/physiology , Glycopeptides/pharmacology , Injections, Intravenous , Myocardial Reperfusion/methods , Peptides, Cyclic/pharmacology , Receptor, Endothelin A , Receptors, Endothelin/physiology , Ventricular Fibrillation/drug therapy , Ventricular Fibrillation/physiopathologyABSTRACT
The aim of this work was to investigate the influence of endothelium-derived nitric oxide and prostaglandins on the contractile responses of isolated dog pulmonary arteries to electrical field stimulation and noradrenaline. Electrical field stimulation (1-8 Hz, 20 v, 0.25 ms duration, for 30 s) produced frequency-dependent contractions that were abolished by tetrodotoxin, guanethidine and, prazosin (all at 10(-6) M). Noradrenaline induced concentration-dependent contractions with an EC50, of 1.85 x 10(-6) M. The increases in tension induced by electrical stimulation and noradrenaline were of greater magnitude in arteries denuded of endothelium. In segments with endothelium, N(G)-nitro-L-arginine methyl ester (10(-4) M) or indomethacin (10(-5) M) had no effects on the basal tone, but significantly enhanced the neurogenic and noradrenaline-induced contractions. The potentiation by N(G)-nitro-L-arginine methyl ester of electrical stimulation-induced contractile responses was partially reversed by L-arginine (10(-4) M). In the presence of N(G)-nitro-L-arginine methyl ester together with indomethacin the electrical stimulation-induced contractile responses were higher than those obtained when only N(G)-nitro-L-arginine methyl ester or indomethacin was used. N(G)-nitro-L-arginine methyl ester and indomethacin did not influence neurogenic-induced contractile responses of endothelium-denuded arteries. The results suggest that endothelial cells of isolated dog pulmonary arteries depress the contractile response to electrical field stimulation of intramural nerves and that endothelium-derived dilator prostaglandins and nitric oxide may interact to inhibit contractile effects of adrenergic stimulation.
Subject(s)
Antihypertensive Agents/pharmacology , Epoprostenol/pharmacology , Nitric Oxide/metabolism , Pulmonary Artery/drug effects , Vasoconstriction/drug effects , Animals , Cyclooxygenase Inhibitors/pharmacology , Dogs , Drug Interactions , Electric Stimulation , Enzyme Inhibitors/pharmacology , Female , In Vitro Techniques , Indomethacin/pharmacology , Male , NG-Nitroarginine Methyl Ester/pharmacology , Norepinephrine/pharmacology , Prostaglandins/metabolism , Pulmonary Artery/physiologyABSTRACT
Goodpasture disease is an autoimmune disorder that occurs naturally only in humans. Also exclusive to humans is the phosphorylation process that targets the unique N-terminal region of the Goodpasture antigen. Here we report the molecular cloning of GPBP (Goodpasture antigen-binding protein), a previously unknown 624-residue polypeptide. Although the predicted sequence does not meet the conventional structural requirements for a protein kinase, its recombinant counterpart specifically binds to and phosphorylates the exclusive N-terminal region of the human Goodpasture antigen in vitro. This novel kinase is widely expressed in human tissues but shows preferential expression in the histological structures that are targets of common autoimmune responses. The work presented in this report highlights a novel gene to be explored in human autoimmunity.
Subject(s)
Autoantigens/metabolism , Collagen Type IV , Collagen/metabolism , Protein Serine-Threonine Kinases/metabolism , Amino Acid Sequence , Autoantigens/chemistry , Base Sequence , Cell Line , Cloning, Molecular , Collagen/chemistry , Humans , Immunohistochemistry , Molecular Sequence Data , Phosphorylation , Protein Biosynthesis , Protein Serine-Threonine Kinases/chemistry , Protein Serine-Threonine Kinases/genetics , Saccharomyces cerevisiae/genetics , Sequence Homology, Amino AcidABSTRACT
Collagen IV is the major component of basement membranes. The human alpha 3 chain of collagen IV contains an antigenic domain called the Goodpasture antigen that is the target for the circulating immunopathogenic antibodies present in patients with Goodpasture syndrome. Characteristically, the gene region encoding the Goodpasture antigen generates multiple alternative products that retain the antigen amino-terminal region with a five-residue motif (KRGDS). The serine therein appears to be the major in vitro cAMP-dependent protein kinase phosphorylation site in the isolated antigen and can be phosphorylated in vitro by two protein kinases of approximately 50 and 41 kDa associated with human kidney plasma membrane, suggesting that it can also be phosphorylated in vivo. Consistent with this, the Goodpasture antigen is isolated from human kidney in phosphorylated and non-phosphorylated forms and only the non-phosphorylated form is susceptible to phosphorylation in vitro. Since this motif is exclusive to the human alpha 3(IV) chain and includes the RGD cell adhesion motif, its phosphorylation might play a role in pathogenesis and influence cell attachment to basement membrane.
Subject(s)
Anti-Glomerular Basement Membrane Disease/immunology , Autoantigens/metabolism , Collagen Type IV , Collagen/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Amino Acid Sequence , Autoantigens/chemistry , Base Sequence , Collagen/chemistry , Humans , Molecular Sequence Data , Oligodeoxyribonucleotides , Phosphorylation , Serine/metabolismABSTRACT
Collagen IV, the major component of basement membranes, is composed of six distinct alpha chains (alpha 1-alpha 6). Atypically among the collagen IV genes, the exons encoding the carboxyl-terminal region of the human alpha 3(IV) chain undergo alternative splicing. This region has been designated as the Goodpasture antigen because of its reactivity in the kidney and lung with the pathogenic autoantibodies causing Goodpasture syndrome. The data presented in this report demonstrate that, in human kidney, the gene region encompassing the Goodpasture antigen generates at least six alternatively spliced transcripts predicting five distinct proteins that differ in their carboxyl-terminus and retain, except in one case, the exon that harbors the characteristic amino-terminus of the antigen. Goodpasture antibodies specifically recognize recombinant proteins representing the antigen and the alternative form that retains the amino-half of the antigen, suggesting that this moiety could be involved in the in vivo binding of the pathogenic antibodies. Furthermore, the sera of control individuals contain autoantibodies against the antigen that can be differentiated from those causing the syndrome based on their specific reactivities, suggesting that the binding of the pathogenic autoantibodies to a specific determinant likely trigger a distinct and unique cascade of events causing the disease.
