Search PubMed⌕ Search

Biomedical subjects

A Castillo

Publications and source records attributed to A Castillo.

At least 73 records · Page 4Linked to original sources
PubMed1995

[Cuban epidemic neuropathy. III. Neutralizing antibodies to the strains isolated and to other enteroviruses in patients and healthy subjects].

Determinations of neutralizing antibodies to the strain 47/93 IPK (CA9) and to the strain 590 were performed in serum samples from patients presenting with epidemic neuropathy and from a group of seemingly healthy subjects. Determinations were also done in the reference strains CA9 and CB1-6 by the microneutralization technique. Patients and their contacts showed significantly higher percentages of neutralizing antibodies to the strain 47/93 than the control group and residents of municipalities with a low rate of the disease. This difference was also confirmed regarding the geometric mean titres with the use of the reference strains CA9 and CB2-4. An increased circulation of the strain 47/93 within the infantile population from 1981 to 1993 was evidenced. Patients exhibited significantly lower percentages and geometric mean titres of neutralizing antibodies to the strain 590 than the control group, despite the fact that in 25/28 certain agents having a mild cytopathogenic effect had been isolated. The possibility of two mechanism of neutralization is stated and an hypothesis on the mechanism by which these viruses may be involved in the pathophysiology of the disease is formulated.

Antibodies, Viral↗
PubMed1995

[The physicochemical characterization of the agents isolated during the outbreak of epidemic neuropathy in Cuba. I].

This paper reports on the physical and chemical characteristics of agents isolated from serum samples of patients presenting with epidemic neuropathy. The behaviour of isolated enteroviruses was as described for such viruses. Mild cytopathogenic effects-producing agents behaved in a variable form regarding sensitivity to chloroform; on the other hand they were neither sensitive to phosphonoacetic acid (PAA) nor to guanidine hydrochloride (GHC1) and grew in cells previously treated with bromodeoxyuridine (BDUR). These results suggest the presence of agents resembling enteroviruses and enveloped viruses. Further studies for the characterization of such agents need to be performed.

Acyclovir↗
PubMed1995

[The physicochemical characterization of the strains isolated during the outbreak of epidemic neuropathy in Cuba. II].

The presence of 2 agents such as a Cox A9 strain and another mild cytopathogenic effect-producing strain, both isolated from patients presenting with epidemic neuropathy is reported in this paper. A mild cutopathogenic effect which was propagated in successive dilutions was developed in the dilution 10(-4) by means of the neutralization test of a Coxsackie A9 virus with its homologous hyperimmune serum. A gradient in saccharose was performed in a mild cytopathogenic effect-producing strain and a typical cytopathogenic effect of an Enterovirus developed from one of the fractions passed in tissular cultures in the presence phosphonoacetic acid (PAA). The possible pathogenic role of these viruses are discussed.

Animals↗
PubMed1995

[The factors affecting the growth of the agent, producing a mild cytopathic effect, isolated in patients with epidemic neuropathy].

Certain factors influencing upon the growth of the agent producer of mild cytopathogenic effect and isolated from the cerebrospinal fluid of patients presenting with epidemic neuropathy are described in this paper. It was demonstrated that a concentration of NaHCO3 was essential for the occurrence of the cytopathogenic effect. Determined concentrations of MnCl2 allowed for the visualization of the cytopathogenic effect and increased viral yields.

Animals↗
PubMed1995

[An immunoenzyme assay for the detection of monoclonal antibodies against the E and NS1 proteins of the dengue virus].

The ELISA was standardized to detect monoclonal antibodies of dengue virus proteins E and NS1. One indirect ELISA was applied, using C6-36 cells inoculated with the A-15 strain, isolated during the dengue 2 epidemic in 1981 as an antigen source. These cells were fixed in ELISA plates at a 200,000 cell/well concentration. A cell control in similar conditions was used. Specific monoclonal antibodies to both proteins were used to standardize the system. Studies at different incubation periods, to determine the highest expression moment of these proteins in the cell membrane, were carried out. The results show a full response at 72 hours postinoculation for both proteins; a 14.7 ng/mL sensitivity was obtained for the detection of NS1, and of 1.43 ng/mL for E protein. This system allows the monoclonal antibodies primary screening to dengue 2 virus E and NS1 proteins.

Aedes↗
PubMed1995

[The usefulness of the CLA-1 cell subline for the isolation of the dengue virus].

The live CLA-1 obtained by cloning from the cell live AP-61 (Aedes pseudocutellaris) was used to intend the isolation of dengue virus in 10 serum samples patients in acute phase and clinical diagnosis of dengue. Samples were parallelly inoculated in C6/36 and AP-61 as control systems. Of the 10 samples, 6 were positive in the 3 systems evidencing sensitivity and usefulness for the isolation of the cell subline CLA-1.

Acute Disease↗
PubMed1994

Presence of double-stranded RNA and virus-like particles in Phaffia rhodozyma.

Four double-stranded RNA (dsRNA) molecules were isolated from Phaffia rhodozyma UCD 67-385. Their molecular sizes were approximately 4.3, 3.1, 0.9 and 0.75 kilobase pairs (kbp) as determined by agarose-gel electrophoresis and they were designated as L, M, S1 and S2, respectively. By differential centrifugation in sucrose gradients, these dsRNAs copurified with isometric virus-like particles 36 nm in diameter. A cured strain, UV-S2, lacking the S2-dsRNA was obtained from P. rhodozyma UCD 67-385 by ultraviolet (UV) light treatment. UV-S2 strain contains identical virus-like particles to those from the wild-type strain, as determined by electron microscopy, suggesting that the S2-dsRNA was not essential for the expression of mycovirus structural polypeptides. On the other hand, both the UCD 67-385 and UV-S2 strains were able to kill P. rhodozyma UCD 67-383, a strain without dsRNAs. These results suggest that the dsRNA molecules also encode a killer system. Finally, the UV-S2 strain maintains killer ability, which suggests that S2-dsRNA is not involved in the killer phenotype expression.

Extrachromosomal Inheritance↗
PubMed1994

Effect of bendazac lysine on lens and retina in diabetics.

The possible beneficial effects on the lens and retina which Bendazac Lysine may have in the treatment of adult diabetic patients were investigated. Twenty patients, ranging in age from 54.80 +/- 5.86 years old, were studied. The average duration of the diabetes was 11.32 +/- 4.10 years. Thirteen patients had background retinopathy. The metabolic controls carried out during the study were satisfactory (HbA1 < 11%). Bendazac Lysine (500 mg three times a day) was administered for 6 months. Blood-retinal barrier permeability (VPR and VPRt) and lens transmittance (t) were evaluated prior to and 6 months after treatment by fluorophotometry. No statistically significant differences between the pre- and post-treatment values of the retina permeability were observed, however, there was a statistically significant improvement (p < 0.05) (initial value: t = 0.813 +/- 0.040 and final value: t = 0.823 +/- 0.037) in the lens transmittance. The authors conclude that Bendazac Lysine has a beneficial effect on the lens in the diabetic adult although no improvement in the permeability of the blood-retinal barrier has been observed.

Administration, Oral↗
PubMed1994

Persistent choroidopathy in systemic lupus erythematosus.

We report a case of a rare entity, choroidopathy in association with systemic lupus erythematosus (SLE), previously described in only twelve patients to our knowledge. It manifested by multiple focal serous elevations of the sensory retina and/or serous detachments of the retinal pigment epithelium bilaterally. No retinal vascular changes were observed. The probable pathogenesis is related to choroidal vascular disease due to systemic hypertension secondary to lupus nephritis, vasculitis, or a combination of these.

Choroid Diseases↗
PubMed1994

Action of sodium fluoride on phagocytosis by systemic polymorphonuclear leucocytes.

Alterations in phagocytosis appear to be important in the onset and development of periodontitis. We investigated new substances that may be of use in the treatment of periodontitis. In a preliminary study, we tested the effect of sodium fluoride on phagocytosis by circulating polymorphonuclear leucocytes (PMNs) in 10 replicate assays using blood from six healthy subjects. Sodium fluoride was tested at concentrations of 1.0 micron to 4.0 microns against Streptococcus oralis, Streptococcus mutans, Streptococcus sobrinus and Streptococcus sanguis. The phagocytic index against all microorganisms increased significantly at all concentrations of sodium fluoride assayed; this effect was dose dependent. Sodium fluoride appeared to stimulate phagocytosis via two mechanisms: an apparent increase in bacterial susceptibility to phagocytosis, and direct stimulation of phagocytosis by PMNs.

Adult↗
PubMed1994

Bacteriological indicators of faecal contamination: result of a loading experiment with untreated urban wastewater.

Some observations were made on the behaviour of total coliforms, faecal coliforms, enterococci, numbers of aerobic bacteria, salmonellas and sulphur-reducing clostridia as bacterial indicators of faecal contamination of groundwater. A controlled irrigation experiment was carried out with untreated residual water in the alluvial aquifer of the Vega of Granada (Spain). The results obtained confirm the value of these parameters are useful indicators of very recent faecal contamination; and changes were detected as the level of the freatic layer increased and the chemical composition of the groundwater changed. These groups of micro-organisms persisted for about 200 h, with the exception of the aerobes which survived for much longer. Salmonellas were present at levels too low to calculate the extent of faecal contamination and sulphur-reducing clostridia were not detected. The results obtained show that irrigation with untreated wastewater offers a lower risk of microbiological contamination of groundwater compared with the direct addition of waters decanted and/or previously filtered.

Bacteria↗
PubMed1994

Physiopathology of primary periodontitis associated with plaque. Microbial and host factors. A review. Part 1.

Microbial factors involved in the genesis of periodontitis include colonization, bacterial penetration of the epithelium, multiplication and invasive-destructive capacity. Colonization of the gingival sulcus is related, to a certain extent, to supragingival plaque. Bacterial multiplication is induced by nutrients in the gingival fluid, and nutrients produced by degradative and excretory microbial activity. Invasion and destruction are mediated by exotoxins, structural elements of the bacteria, enzymes, metabolites, polyclonal lymphocyte activity, fibroblastic cytotoxicity, and leukocyte chemotactic inhibition.

Bacteria↗
PubMed1994

Physiopathology of primary periodontitis associated with plaque. Microbial and host factors. A review. Part 2.

To a considerable extent, host factors condition the initiation and progression of periodontitis. The integrity of the periodontal structures and the immune elements in the gingival fluid may act as a defensive barrier against microorganisms. However, immune over-response may lead to tissue damage and bone resorption from anaphylactic reactions, immunocomplex reactions, type IV hypersensitivity, complement hyperactivation via the alternative pathway, or direct action of leukocytes and macrophages. Moreover, insufficient host response allows bacteria to escape control, allowing more rapid progression of the disease.

Bacteria↗
PubMed1994

A study on the antigenic nature of circulating immune complexes in hemolytic uremic syndrome: no evidence of platelet membrane glycoprotein antigens.

Circulating immune complexes (CIC) have been described in the hemolytic uremic syndrome (HUS) in children. They may represent an epiphenomenon or could be related to the platelet activation and endothelial damage observed in this disease. In an attempt to define this relationship, we investigated the CIC isolated in 17 patients with the classic form of HUS, by means of monoclonal antibodies against platelet surface glycoprotein Ib and IIb-IIIa complex. The negative results obtained do not support the possibility of platelet antigens being constituents of CIC and make an antibody-induced platelet activation in HUS very unlikely.

Antibodies, Monoclonal↗
PubMed1994

[Detection of immunoglobulin A in serum and saliva of patients with hepatitis A].

Specific secretory serum IgA antibodies to the hepatitis A virus from samples from patients with clinical symptoms compatible to hepatitis A, their contacts, and healthy subjects were analyzed using an ELISA technique; results were compared with those of specific serum IgM antibodies to the hepatitis A virus. The following results were attained in 175 blood samples: coincidence by 98.8%; sensitivity by 96.8%; and specificity by 100%. Two cases were negative to IGA and positive to IGM. On comparing the presence of IGA in saliva with the presence of IGM in blood, coincidence was of 88.1%; sensitivity, of 40.9% and specificity, of 100%. Of the 22 cases with positive IGM in blood, only 9 showed specific IGA antibodies in the saliva. The 111 cases who had negative IGM in blood were also negative to IGA. The obtained data suggest that specific serum IGA antibodies to the hepatitis A virus are an indicator of a recent or occurrent infection due to this virus and thus it may be considered and alternative for the diagnosis of this disease.

Enzyme-Linked Immunosorbent Assay↗
PubMed1993

Antineutrophil-cytoplasmic-autoantibodies in poststreptococcal nephritis.

Sera from 210 patients with APSGN, were tested for the presence of ANCA (IgG-isotype). Indirect immunofluorescence (IF) on ethanol fixed human PMNs was used, and for those positive sera, ELISA kits for PR3 (Proteinase 3) and MPO (Myeloperoxidase) was performed. ANCA were detected in 9% (18 out of 210 cases) in a predominantly diffuse cytoplasmic staining pattern in 14 cases (77%), and in a perinuclear pattern in the remaining 4 cases (22%). Anti-MPO was found in 4 cases (C-ANCA 3; P-ANCA 1) and anti-PR3 was always negative. The presence of ANCA was significantly associated with a more severe glomerular disease as assessed by the serum creatinine value and the crescents formation. Longitudinal studies performed in 11 cases have shown that raised levels of these autoantibodies may persist for at least six months, without relationship with disease activity. Further studies are required to dilucidate the specificity of these autoantibodies, and if its presence is either an epiphenomenon of the heterogeneous humoral immune response in streptococcal infection, or they play some pathogenic role in APSGN.

Adolescent↗