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Biomedical subjects

M Pardo

Publications and source records attributed to M Pardo.

At least 73 records · Page 4Linked to original sources

Long-term follow-up study of serum IgM antibody to hepatitis C virus (HCV), HCV replication, and liver disease outcome in chronic hepatitis C.

IgM anti-hepatitis C virus (HCV) and HCV RNA were longitudinally tested for 4.0-8.7 years in 40 patients with chronic HCV infection. Patients in disease remission usually lost IgM anti-HCV and HCV RNA, but most patients experiencing disease reactivation had increased levels of the IgM antibody or it reappeared before the biochemical relapse, even when HCV RNA was undetectable. IgM anti-HCV was detectable in most patients with ongoing viral replication and persistent liver disease. Despite long-term disease remission, IgM anti-HCV may persist and be detectable with or without evidence of serum HCV RNA; this indicates a possible disease reactivation, which could occur after several years of sustained transaminase normalization. Detection of IgM anti-HCV in chronic hepatitis C indicates an active immune response to persistent viral infection and should, therefore, be considered as a sensitive marker of active HCV replication and HCV-associated liver disease.

Adult↗

Evidence of subtype-specific antibodies to antigenic epitopes in the NS5 region of hepatitis C virus in the circulation of patients with chronic hepatitis C.

The antigenicity of the NS5 region of type 1 hepatitis C virus (HCV) was investigated by epitope mapping of the region spanning amino acids 2530 to 2723 of the HCV polyprotein. Six antigenic regions were recognized by anti-HCV positive sera from individuals with chronic hepatitis C in a modified enzyme-linked immunosorbent assay with synthetic oligopeptides. Five of these regions demonstrated intra-type 1 sequence variations defining subtype 1a and 1b HCV sequences. The region between amino acids 2623 and 2634 allowed testing of subtype-specific anti-NS5 antibodies; serological reactivity to subtypes 1a and 1b was observed in 27 and 61%, respectively, of 150 cases with chronic hepatitis C. Simultaneous reactivity to subtypes 1a and 1b was found in 23% of the patients. Detection of subtype-specific anti-NS5 antibody correlated in more than 80% of the cases with the HCV genotype (subtypes 1a and 1b) analyzed by PCR amplification of the NS5 sequence. These data provide evidence of the existence of a subtype-specific anti-NS5 response in the circulation of patients with chronic hepatitis C.

Adolescent↗

Evaluation of serological tests for diagnosis of Brucella melitensis infection of goats.

Five serological assays were evaluated for the diagnosis of brucellosis in goats: the rose bengal test (RBT), complement fixation test (CFT), radial immunodiffusion (RID) with Brucella and Yersinia enterocolitica O:9 polysaccharides, counterimmunoelectrophoresis (CIEP) with cytosol, and enzyme-linked immunosorbent assay (ELISA) with polyclonal and protein G conjugates and smooth lipopolysaccharide (S-LPS), native hapten polysaccharide (NH), or cytosol antigens. For optimal sensitivity, RBT had to be used with sera-antigen at a 3:1 dilution. In the RID test, Brucella melitensis biotype 1 NH could not be replaced by Brucella abortus biotype 1 or Y. enterocolitica 0:9 polysaccharides. In the ELISA, S-LPS and NH gave similar results and the protein G conjugate increased the specificity. With the sera from 55 B. melitensis culture-positive goats, the sensitivity was 100% for RBT, CFT (titer > or = 4), and ELISA with S-LPS or NH; 94% for RID; and 93% for CIEP. All tests were negative (100% specific) when testing the sera from 127 brucella-free goats. Larger discrepancies among the results of the serological tests were obtained with sera from goats of areas where brucellosis is endemic. When the sera of 20 young goats vaccinated subcutaneously (10(9) CFU of B. melitensis Rev 1) and bled 6 months later were examined, the specificities were as follows: NH ELISA, 60%; CFT and S-LPS ELISA, 75%; RBT, 80%; CIEP, 90%; and RID, 94%. With the sera from 10 young goats vaccinated conjunctivally (10(9) CFU of B. melitensis Rev 1) all tests were 100% specific 4 months after vaccination. The proportion of goats giving a positive reaction after vaccination decreased faster in RID than in other tests.

Animals↗

Gastric carcinoma: curative resection and adjuvant chemotherapy.

A retrospective study of gastric adenocarcinoma treated with surgery as curative attempt was performed at the Oncology Service, in the Hospital Regional 20 de Noviembre, ISSSTE. Morbidity and mortality of the surgical procedures were evaluated, the significance of several risk factors and the survival impact of adjuvant chemotherapy with 5-fluorouracil (5-FU) and mitomycin C (MMC). In the period from 1975 to 1991 a total of 483 new cases were seen. In only 54 patients (11.2%) was it possible to undertake a curative resection. The patients were assigned to three groups of treatment: surgery alone (14 cases), surgery + 5-FU (19 cases), and surgery + 5-FU+MMC (21 cases). Three different types of surgical techniques are regularly performed in our service for gastric cancer treatment: Billroth II distal gastrectomy, total gastrectomy with Roux-En-Y reconstruction, and esophagogastrectomy with esophagogastrostomy. Surgical morbidity and mortality was low, with 9% of duodenal stump fistulas and 27% with partial stenosis of esophagojejunostomy; the operative mortality was zero. Chemotherapy toxicity was transient and low, no related deaths were recorded. The prognostic factors associated significantly with survival were lymph node status and tumor penetration. The histologic differentiation as well as the tumor location and type of surgery had no significance. The estimated 5-year survival of the patients treated with surgery alone was 62%, while that of the patients treated with surgery plus chemotherapy was 38%. These groups were not comparable, however, because of important differences in their prognostic factors. The groups treated with 5-FU alone or in combination with MMC had no survival difference between them.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma↗

Persistence of müllerian derivatives, lymphangiectasis, hepatic failure, postaxial polydactyly, renal and craniofacial anomalies.

We describe 3 unrelated newborn males with a previously unreported constellation of congenital anomalies. All 3 died neonatally of hepatic failure. Clinically, they presented with a pattern of malformations characterized by prenatal linear growth deficiency, hypertrophied alveolar ridges, redundant nuchal skin, and postaxial polydactyly. All 3 cases had male external genitalia with cryptorchidism, and 2 of them, a small penis. Necropsies showed similar internal anomalies, consisting of müllerian duct remnants, lymphangiectasis, and renal anomalies. The karyotypes were normal (46, XY) in skin fibroblasts (Case 1) and in peripheral blood lymphocytes (Case 3). Although this pattern of congenital anomalies must be differentiated from several other lethal syndromes, to our knowledge, no similar cases have been described previously. Cause of this syndrome is unknown. Because Case 2 had a previous brother with similar anomalies, we suspect that this new entity probably is an autosomal recessive or X-linked trait.

Abnormalities, Multiple↗

Insulinlike growth factor I and interleukin 1 beta messenger RNA in a rat model of granulomatous enterocolitis and hepatitis.

BACKGROUND: Insulinlike growth factor I (IGF-I) is mitogenic for fibroblasts and smooth muscle cells and stimulates collagen synthesis. The present study tested the hypothesis that IGF-I is important in the development of granulomatous inflammation and fibrosis. METHODS: IGF-I messenger RNA (mRNA) was measured in bowel and liver of rats with peptidoglycan-polysaccharide-induced chronic granulomatous enterocolitis and hepatitis using RNase protection. Cellular sites of IGF-I mRNA and IGF-I peptide precursor were localized by in situ hybridization and immunohistochemistry, respectively. Sites of IGF-I synthesis were compared with sites of interleukin 1 beta mRNA expression. RESULTS: IGF-I mRNA was increased 3.7-fold in cecal tissue from peptidoglycan-polysaccharide-injected rats compared with controls. IGF-I mRNA was up-regulated in fibroblastlike cells in the intensely fibrotic periphery of cecal and hepatic granulomas. This region also expressed IGF-I peptide precursor. Interleukin 1 mRNA localized to macrophage-like cells in the center of granulomas. CONCLUSIONS: IGF-I may be important in the development of fibrosis in this model of Crohn's disease. The localization of IGF-I and interleukin 1 mRNAs to distinct but adjacent sites is consistent with a paracrine interaction between cells expressing IGF-I and interleukin 1.

Animals↗

Tetraploidy in a liveborn infant.

We report a 3 month old boy with tetraploidy, found in peripheral blood and skin fibroblast cultures, with severely delayed growth and neurodevelopment, and with a cleft lip; these findings have not been described before. This report brings to seven the total number of liveborn infants with a 92,XXYY karyotype.

Abnormalities, Multiple↗

Artificial insemination with husband's sperm (AIH): techniques for sperm selection.

Artificial insemination with husband's sperm (AIH) attempts to treat infertile couples by solving their particular infertility problems. This review is concerned with detailing and evaluating the experiences of different authors with AIH in infertile couples, types of insemination, and indications for insemination, with emphasis on techniques for sperm selection and separation: glass-wool filtration, separation on albumin columns, washed sperm, swim-up method, and spermatozoa selection in Percoll gradients.

Female↗

Spermatozoa selection in discontinuous Percoll gradients for use in artificial insemination.

In a preliminary study of the ejaculate of 93 men, changes in motility and hypo-osmotic swelling before and after sperm separation by discontinuous Percoll gradients were evaluated. Both parameters improved significantly (P less than 0.01) in Percoll-separated spermatozoa. In a second stage, 99 couples underwent intrauterine insemination of separated semen by Percoll gradients. The population had infertility for a mean of 5.6 years. In a 1-year period, a total of 344 intrauterine insemination cycles were completed. Failure was considered when conception did not occur within four treatment cycles. The mean number of cycles per successful couple before pregnancy was 1.52. An overall 21% pregnancy rate was achieved (16% for oligoasthenospermia and 24% for asthenospermia). Sperm separation in Percoll gradients is a useful technique for intrauterine insemination in some cases of male subfertility.

Adult↗

[Results of conjugal artificial insemination using Percoll].

Selection of spermatozoa on Percoll's medium has enabled to obtain 33 pregnancies in 217 couples. This simple and inexpensive technique, which is most successful during the first nine months, deserves to be attempted, in case of deficient sperm, before contemplating more complex techniques.

Adult↗

Human choriogonadotropin-like material in bacteria of different species: electron microscopy and immunocytochemical studies with monoclonal and polyclonal antibodies.

Immunocytochemical studies using antisera to whole human choriogonadotropin (hCG), to its alpha- and beta-subunits and to the COOH-terminal peptide of hCG beta, and two monoclonal antibodies to hCG beta, demonstrated expression of hCG-like material, its individual subunits and/or fragments in nine bacterial strains. Seven of these were isolated from patients with cancer and were definitely identified as Streptococcus faecalis (three strains), Staphylococcus haemolyticus (two strains) and Staphylococcus epidermidis and Escherichia coli (single strains). The other two strains were cell-wall-deficient (CWD) variants, one identified as Streptococcus bovis, isolated from the blood of a patient with a fever of unknown origin and a possible brain abscess. The other was a Gram-negative diphtheroid isolated from the urine of a pregnant woman, which during the period of study reverted to a Gram-positive Corynebacterium identified as a 'C. ulcerans' strain and expressed the hCG-like factor only during its phase as Gram-negative diphtheroid. Electron microscopy of these nine strains (including negative controls of strains of the same species subjected to the same immunocytochemical analyses and under identical cultural conditions) revealed morphological alterations in the bacterial cell walls and cytoplasmic material and/or bizarre forms of reproduction in six of the nine strains expressing hCG-like material including the two CWD variants. Collectively, these results provided evidence that (1) hCG-producing bacteria isolated from patients with overt cancer are not a new and unique species as claimed by others, and (2) there is a close resemblance between the bacterial protein and the human trophoblastic hormone, based on immunochemical recognition of different parts of the hCG molecule.(ABSTRACT TRUNCATED AT 250 WORDS)

Antibodies, Monoclonal↗

Combined antihistamine antagonism of the flushing reaction to alcohol.

The so-called Oriental flushing reaction associated with ingestion of small amounts of alcohol was antagonized by combined antihistamine administration. In stage one of the study, the flushing reaction to low doses of alcohol was produced in Orientals. Most subjects experienced a cutaneous flush, increase in skin temperature, decrease in blood pressure, increase in pulse rate and subjective symptoms such as dizziness, sleepiness, anxiety, headache, generalized weakness and nausea. One half of the group of subjects was then given diphenhydramine, 50 mg (H1 receptor antagonist) and cimetidine, 300 mg (H2 receptor antagonist) and the second half received placebo tablets before the administration of alcohol. The clearest difference between the antihistamine group and placebo group was in the skin flushing reaction. The antihistamine group showed a statistically significant reduction in the skin flush. The antihistamines also neutralized the systolic hypotension induced by the administration of alcohol.

Adult↗

Prevention of oncogenic viral infections in mice with CGP 11637, a synthetic muramyl dipeptide analog.

The efficacy of N-acetyl-nor-muramyl-L-alanyl-D-isoglutamine (nor-MDP) in controlling viral oncogenesis in mice was investigated. The tumors studied were blood cell malignancies induced by Friend leukemia virus in SJL/J mice, spontaneous mammary neoplasms in RIII/Imr and C3H/OuJ mice, and spontaneous lymphocytic leukemia in AKR/J mice. A transplantable tumor, Lewis lung carcinoma, in C57BL/6J mice was used as a nonvirally induced control model. The nor-MDP was dissolved in saline and made into an emulsion with an equal volume of squalene-Arlacel A and injected subcutaneously at 1- to 2-month intervals. Test and control mice were challenged with exogenous virus or tumor transplant 2 weeks after a second injection of nor-MDP. Administration was started at around 2 months of age in mice that develop spontaneous neoplasms. Electron microscopy studies were done on neoplastic tissues of selected test and control mice. This administration of nor-MDP prevented erythroleukemia in SJL/J mice caused by low doses of Friend leukemia virus (although erythroleukemia survivors were not protected from a late-developing lymphoma) and also delayed (possibly prevented) the development of a spontaneous mammary neoplasm in RIII/Imr mice. No antitumor effects were observed on the spontaneous neoplasms of C3H/OuJ and AKR/J mice or on the Lewis lung carcinoma implanted into C57BL/6J mice. Electron microscopic examinations of the various neoplastic tissues indicated that nor-MDP administration eliminated or reduced extracellular viruses. The results suggested that under the experimental conditions used nor-MDP appears to effect the viruses and not the malignant cells per se.

Acetylmuramyl-Alanyl-Isoglutamine↗

Talwin addict nephropathy.

Three patients with a 2-3 year history of parenteral abuse of pentazocine hydrochloride (Talwin) developed membranoproliferative glomerulonephritis type I. Clinical presentation included nephrotic syndrome, microscopic hematuria, and hypertension. Tissue studies disclosed 1+ to 4+ mesangial and subendothelial deposits of immunoglobulins (predominantly IgM) and complement components C1Q, C3 and C4 with focal reduplications of glomerular basement membranes. Glomerular C3 receptor studies performed on one patient demonstrated diffuse loss of receptor activity correlating with localization of immune deposits. Serum studies showed decreased levels of C3, elevated levels of IgM (greater than 2 SD) (three patients) and circulating immune complexes (two patients). Repeated blood and urine cultures were negative. Immune mechanisms may be involved in the pathogenesis of Talwin addict nephropathy.

Adult↗