PubMed Health⌕ Search

Biomedical subjects

J Domínguez

Publications and source records attributed to J Domínguez.

At least 127 records · Page 7Linked to original sources

[Chemoembolization in the treatment of hepatocarcinoma].

Transcatheter arterial chemoembolization with lipiodol and adriamycin was performed in 46 patients with hepatocellular carcinoma (HCC). In 27, this procedure was followed by selective arterial embolization using gelatin sponge particles. Surgical resection was carried out in 5 cases and 13 patients were transplanted (OLT). The aim of the study was to analyze the survival and degree of tumor necrosis. In the nonsurgical group the overall survival was 67% after 24 months in the OKUDA I stage, 31% after 20 months in the OKUDA II stage and 25% after 6 months in the OKUDA III stage. For the patients who underwent surgery, survival was 38% after 20 months in 5 patients who were resected and 72% after 24 months in 13 patients who were transplanted. Transcatheter arterial chemoembolization improves survival in patients who are not operated on, and can be used as a complementary treatment for patients who undergo surgery. A full tumor necrosis was observed in well encapsulated tumors.

Carcinoma, Hepatocellular↗

[Vascular compression of the duodenum related to a plaster cast (the cast syndrome)].

Case report of a 15-year-old girl presenting compression of the duodenum by the superior mesenteric artery, occurring after the application of a body plaster cast for correction of a idiopathic thoracic scoliosis, which required a gastrojejunostomy. The clinical and radiological pictures of this case fall into the rare entity called the "cast syndrome". The salient features of this syndrome are commented.

Adolescent↗

Spleen abscess caused by Eikenella corrodens.

A case is reported of splenic abscess due to Eikenella corrodens, a gram-negative rod which is found as part of normal flora in human mucous surfaces. A 64-year-old man presented with fever, chills, anorexia and abdominal pain. Abdominal ultrasound examination showed a perisplenic fluid collection which was considered to be either blood or a subcapsular spleen abscess. The presence of a splenic abscess was later confirmed during surgery and a splenectomy was performed. Splenic purulent material and blood cultures yielded Eikenella corrodens. The patient received cefotaxime for 19 days and was discharged asymptomatic.

Abscess↗

Analysis of T lymphocyte subsets proliferating in response to infective and UV-inactivated African swine fever viruses.

The proliferative response to infective and UV-inactivated African swine fever virus was analyzed in cells from pigs surviving an experimental infection with attenuated virus. All the pigs showed strong dose-dependent proliferative responses to both infective and UV-inactivated virus. This response was also observed when nitrocellulose-bound solubilized virus proteins were used in the assay. Heterologous isolates also induced proliferation, however it was significantly lower than that induced by the isolate used to infect the animals. The response to infective virus was blocked equally by anti-CD4 and anti-CD8 monoclonal antibodies (mAb); the response to UV-inactivated virus was almost abolished by anti-CD4 and 60% inhibited by anti-CD8 mAb. FACS analysis of 28-day T cell lines derived from peripheral blood mononuclear cells demonstrated the progressive increase of the CD8+ subset when the cells were stimulated with infective virus, whereas the stimulation with UV-inactivated virus induced the increase of both CD4+ and CD8+ subsets. In this case, the sum of CD4+ and CD8+ percentages was higher than the total percentage of T cells, suggesting the presence of cells positive for both CD4+ and CD8+.

African Swine Fever↗

Trout immunoglobulin populations differing in light chains revealed by monoclonal antibodies.

Monoclonal antibodies (MAbs) raised against trout immunoglobulin (Ig) recognize two independent Ig populations differing in the molecular weight of L chains. The trout Ig population recognized by MAb 2H9 represented congruent to 20% of the total Ig and contained L chains congruent to 26 kDa, whereas the trout Ig population defined by MAb 2A1 comprised 11% of the total Ig and possessed L chains congruent to 24 kDa. The determinants recognized by these MAbs reside on L chains as determined by ELISA using mildly reduced H and L chains. The size heterogeneity of the L chains was not due to differences in glycosylation. Partial peptide maps showed structural differences between both L chains. Both Ig populations were found in each of the 30 trout sera tested. These data extend the existence of L chains diversity in fish, recently described in catfish, to other teleosts.

Animals↗

One-step purification of the major rainbow trout immunoglobulin.

Salmonid immunoglobulin purification has been hampered by time-consuming, labour-intensive, conventional chromatographic procedures. In this report we describe the use of immunoaffinity chromatography for the purification of immunoglobulins from trout serum in a single step. An anti-heavy chain monoclonal antibody (1G7) which reacts with more than 85% of total trout immunoglobulins was used to purify the trout immunoglobulin. The purity achieved was higher than 95%, and the immunoglobulins recovered were fully immunogenic. This method served equally well in isolating immunoglobulins from the sera of other salmonids (coho salmon and chinook salmon). The procedure should be useful in the standardization of salmonid immunoglobulin reagents.

Animals↗

Rapid serotyping of infectious pancreatic necrosis virus by one-step enzyme-linked immunosorbent assay using monoclonal antibodies.

A one-step ELISA has been developed for detection and serotyping of infectious pancreatic necrosis virus (IPNV) in infected cell cultures using monoclonal antibodies (mAb) raised against strains representing the Sp, Ab and VR 299 serotypes of IPNV. This assay uses a serotype-specific mAb as capture and a mAb directed against a common epitope as detector antibody. Avidin-peroxidase was employed for amplification. The assay was performed in 90 min by simultaneous incubation of the samples, the biotin labelled mAb and the avidin-peroxidase, and detected 37 ng/ml of purified virus. Serotyping of 34 isolates from different areas of Europe, Asia and America showed a total concordance with the results obtained by the neutralization assay.

Animals↗

[Evaluation of 5 selection criteria for sputum as a valid sample for culture].

We compare five selection criteria to discriminate between good quality expectorated sputum and specimens contaminated with upper respiratory tract secretions. We employed two microscopic methods (Bartlett, Heineman) which rely upon the number of squamo-epithelial cells and polymorphonuclear leucocytes; and a macroscopic method (the Medical Research Council) which evaluates the gross appearance of sputum, with three different criteria for admission established by our own. Three hundred and thirty two sputum were included. We evaluated sensitivity, specificity and predictive values as compared with isolation or not of a potential pathogen. We obtained 72% and 45% sensitivity, and 81% and 86% specificity for Bartlett and Heineman methods respectively. Most restrictive criterion for macroscopic method provided 57% sensitivity and 82% specificity; least restrictive showed 97% sensitivity and 17% specificity. Macroscopic method is a quick, valuable screening for discarding sputum contaminated with upper respiratory tract secretions.

Bacteria↗

[Upper digestive hemorrhage caused by ulcerated periampullary leiomyoma].

Duodenal leiomyoma represents a very unusual cause for acute gastrointestinal bleeding. The authors report the case of a 49-year-old male with a massive bleeding from an ulcerated duodenal leiomyoma involving the ampulla of Vater. An emergency Whipple's pancreaticoduodenectomy was carried out under suspicion of local malignancy. It is emphasized that the proper diagnosis of smooth muscle tumors is often difficult, both clinically and from the pathological point of view.

Ampulla of Vater↗

Common antigenic determinants of the tubulin binding domains of the microtubule-associated proteins MAP-2 and tau.

The structural-functional aspects of the tubulin binding domain on the microtubule-associated protein MAP-2, and its relationship with the tubulin binding domain on tau, were studied using anti-idiotypic antibodies that react specifically with the epitope(s) on MAPs involved in their interaction with tubulin in addition to other tau and MAP-2 specific antibodies. Previous studies showed that MAP-2 and tau share common binding sites on tubulin defined by the peptide sequences alpha (430-441) and beta (422-434) of tubulin subunits. Furthermore, binding experiments revealed the existence of multiple sites for the interaction of the alpha- and beta-tubulin peptides with MAP-2 and tau. Most recent studies showed that the synthetic tau peptide Val187-Gly204 (VRSKIGSTENLKHQPGGG) from the repetitive sequence on tau defines a tubulin binding site on tau. Our present immunological studies using anti-idiotypic antibodies which interact with the synthetic tau peptide and antibodies against the Val187-Gly204 tau peptide indicate that MAP-2 and tau share common antigenic determinants at the level of their respective tubulin binding domains. These antigenic determinants appear to be present in the 35 kDa tubulin binding fragment of MAP-2 and in 18-20 kDa chymotryptic fragments containing the tubulin binding site(s) on MAP-2. These findings, along with structural information on these proteins, provide strong evidence in favor of the hypothesis that tubulin binding domains on MAP-2 and tau share similar structural features.

Amino Acid Sequence↗

Epitope mapping of the major allergen from yellow mustard seeds, Sin a I.

The antigenic sites on the major allergen from yellow mustard (Sinapis alba L.) seeds were studied using murine (BALB/c) monoclonal antibodies (mAb) and human IgE antibodies. Ten IgG1 (K) mAb from two fusions were analyzed. Competition and complementation studies performed with peroxidase labeled mAb reveal the existence of two main antigenic sites in Sin a I. All the described mAb failed to recognize the unordered carboxyamidomethylated polypeptide chains, with the single exception of 2B3, which binds the alkylated large chain. However, this mAB cannot react with the tetranitromethane-modified protein which retains the native conformation. This fact suggests that the only tyrosine of Sin a I, located in the large chain, may be part of a sequential epitope of the allergen. This chemical modification also alters the binding of the mAb 4A11 and 3F3 to the allergen, besides 2B3. The three mAb belong to the same complementation group. Specific IgE binding cannot be inhibited either by the large or small carboxyamidomethylated polypeptide chains, while the nitrated allergen shows a weaker inhibitory activity than the native Sin a I. 4A11, which is a tyrosine-dependent mAb, causes the greatest binding inhibition of the tested mAb on human IgE from atopic individuals, as determined from a reverse enzyme immunoassay, suggesting an important role played by tyrosine in the immunochemical recognition of Sin a I.

Allergens↗

Evaluation of an enzyme-linked immunosorbent assay to detect specific antibodies in pigs infested with the tick Ornithodoros erraticus (Argasidae).

Ornithodoros erraticus is known to transmit the virus that causes the highly contagious disease, African Swine Fever, in Spain. As part of the disease eradication campaign, an ELISA test to detect specific antibodies against the tick was developed. The ELISA, using salivary gland preparations as an antigen, showed high sensitivity and was able to detect as few as 10 adult ticks. The specific antibodies were detected in the sera 6 weeks after the primary infestation and strongly increased after the challenge. The utility of this test under field conditions was also tested.

Animals↗

Effect of lipid infusion on substrate uptake in soleus muscle of the cat.

Uptake of glucose, free fatty acids (FFA) and lactic acid was studied in soleus muscle of heparinized cats under pentobarbital anesthesia. Cats were separated in 3 groups: caged, "free" and exercised. Blood samples were taken from an artery and the venous effluent of the muscle, a) at rest, b) after contraction, c) after Intralipid infusion, d) after a post-infusion contraction. Glucose was released in some muscles in a) and b), but uptake predominated in c) and d). There was a direct relationship between glucose uptake and lactic acid production only in muscles of exercised cats in a). Venous FFA levels correlated with lactic acid release in b) and d). Results indicated that in the studied conditions soleus muscle of the cat, which is formed by slow oxidative fibres, utilized FFA as the main fuel; glycogen was used during contraction producing a non significant increase in lactic acid. The inhibition by FFA of pyruvate entrance to the TCA cycle, was suggested by the direct correlation between venous FFA levels and lactic acid release.

Animals↗

Naloxone potentiation of cardiovascular responses to sympathomimetic amines in the rat.

The work was aimed at analyzing the ability of naloxone to potentiate 1) the arterial pressure responses to sympathomimetic amines administered i.v. in normotensive anesthetized, pithed, chemically sympathectomized or acutely adrenalectomized rats and 2) the chronotropic responses to norepinephrine in the isolated rat atria. In anesthetized rats, naloxone (2.5-10 mg/kg i.v.) potentiated the pressor responses to epinephrine (2 micrograms/kg). Naloxone (5 mg/kg) significantly potentiated the pressor responses to norepinephrine (1-4 micrograms/kg), phenylephrine (10-50 micrograms/kg) and the reflex pressor responses to a 60-sec carotid occlusion. On the contrary, naloxone did not potentiate the arterial pressure responses to methoxamine (100 micrograms/kg), angiotensin (0.5-2 micrograms/kg) and isoproterenol (1 micrograms/kg). Pithing or acute adrenalectomy did not alter the naloxone-induced potentiation of the pressor responses to norepinephrine (0.125-0.5 micrograms/kg). 6-Hydroxydopamine pretreatment abolished completely the naloxone-induced potentiation of the pressor responses to norepinephrine (0.25-1 micrograms/kg). In isolated rat atria, naloxone (1.4 and 2.8 x 10(-5) M) potentiated the chronotropic responses to norepinephrine (1.5-6 x 10(-8) M). It is suggested that naloxone potentiates cardiovascular responses to sympathomimetic amines by interacting with presynaptic adrenergic mechanisms which could additionally contribute to its pressor effects in acute hypotensive conditions.

Angiotensins↗

Purification and characterization of an allergen of mustard seed.

A protein allergen has been isolated from mustard seed extracts by gel filtration. In RAST-inhibition experiments the allergen inhibited more than 60% of the binding of mustard-specific IgE from a pool of seven patients' sera. The allergenic activity was also demonstrated by histamine release from whole blood from two sensitive patients. The allergen had an isoelectric point close to 10.5 and an apparent molecular weight of 14,000. It was stable in alkaline and acid solutions and showed resistance to heating and to degradation by proteolytic enzymes.

Allergens↗

[Initial evaluation of aluminum concentrations in patients with nephropathy and undergoing hemodialysis at the Miguel Pérez Carreño Hospital and the University Hospital of Caracas (Venezuela)].

The present work reports the concentrations of aluminum in whole blood and dialysis solutions of 27 patients with chronic renal failure and under hemodialysis treatment at Miguel Pérez Carreño and University Hospitals, both from Caracas city. Aluminum levels of the water used to prepare the dialysates were also monitored and the metal mobilization during dialysis studied. Patients' mean blood aluminum concentrations (ca. 34 micrograms AI/L) were lower than those of renal individuals from Maracaibo (ca. 58 micrograms AI/L), situation related to the low metal contents of the dialysate water (ca. 14 micrograms AI/L). In addition, Caracas drinking water showed up very high aluminum concentrations, above 475 micrograms/L. There was a relationship between the renal patients' blood aluminum concentrations and (1) the metal contents of the dialysis solutions and (2) the ingestion of aluminum hydroxide-based antacids. Aluminum transfer incorporation processes toward the patients' blood were observed in both dialysis units. This was due to the favorable concentration gradients (blood aluminum concentration/dialysate aluminum concentration) established at the start of every hemodialysis treatment.

Adult↗