Search PubMed⌕ Search

Biomedical subjects

A Campos

Publications and source records attributed to A Campos.

At least 91 records · Page 5Linked to original sources
PubMed1997

Effect of Anapsos (Polypodium leucotomos extract) on in vitro production of cytokines.

AIMS: The aim of the study was to test the immunomodulating capacity of Anapsos, Polypodium leucotomos extract, in vitro in an attempt to explore how this extract acts from an immunological point of view and thus to identify a common link capable of explaining most of its effects. METHODS: Polypodium leucotomos rhizomes were harvested in Guatemala and the extract, Anapsos, obtained. Mononuclear cells were obtained by density gradient centrifugation from healthy donors, and stimulated with phytohemagglutinin or Pokeweed with and without Anapsos and with Anapsos alone. Cell proliferation was determined by thymidine incorporation. Cells were also stimulated and the following cytokines determined by ELISA at 0, 12, 24, 48, 72, and 96 h: IL-1 beta, TNF-alpha, IL-2, INF-8, IL-4 and IL-10. RESULTS: Anapsos, Polypodium leucotomos extract, has a modulating effect on the in vitro production and release of cytokines by peripheral blood mononuclear cells of healthy subjects. At doses effective in vivo, Anapsos can stimulate PBMNc proliferation, delay IL-1 beta secretion and at the same time increase that of IL-2, IL-10, and INF-gamma. CONCLUSIONS: Anapsos may have an antagonistic effect on some of the cytokines released on cell stimulation with LPS and/or PHA, which suggests that this product has a pleiotropic effect on different populations in the immune system.

Adult↗
PubMed1997

Structural and genetic analysis of a mutant of Rhodobacter sphaeroides WS8 deficient in hook length control.

Motility in the photosynthetic bacterium Rhodobacter sphaeroides is achieved by the unidirectional rotation of a single subpolar flagellum. In this study, transposon mutagenesis was used to obtain nonmotile flagellar mutants from this bacterium. We report here the isolation and characterization of a mutant that shows a polyhook phenotype. Morphological characterization of the mutant was done by electron microscopy. Polyhooks were obtained by shearing and were used to purify the hook protein monomer (FlgE). The apparent molecular mass of the hook protein was 50 kDa. N-terminal amino acid sequencing and comparisons with the hook proteins of other flagellated bacteria indicated that the Rhodobacter hook protein has consensus sequences common to axial flagellar components. A 25-kb fragment from an R. sphaeroides WS8 cosmid library restored wild-type flagellation and motility to the mutant. Using DNA adjacent to the inserted transposon as a probe, we identified a 4.6-kb SalI restriction fragment that contained the gene responsible for the polyhook phenotype. Nucleotide sequence analysis of this region revealed an open reading frame with a deduced amino acid sequence that was 23.4% identical to that of FliK of Salmonella typhimurium, the polypeptide responsible for hook length control in that enteric bacterium. The relevance of a gene homologous to fliK in the uniflagellated bacterium R. sphaeroides is discussed.

Amino Acid Sequence↗
PubMed1997

Cholera and myocarditis--a case report.

The authors describe the case of a fifty-nine-year-old white man, previously in good health, who initiated his present illness with acute episode of enterocolitis characterized by mild fever and, in the next eight hours, twenty-four episodes of watery diarrhea, nausea and vomiting, as well as generalized sweating and severe weakness secondary to hypovolemia and electrolyte disorder. These complications were corrected in seventy-two hours in the intensive care unit. Two days later, when the patient was stable hemodynamically, under cardiac monitoring and with normal laboratory studies including serum electrolytes, he developed electrocardiographic changes characterized by trifascicular block (prolonged P-R interval, complete right bundle branch block [CRBBB] and left posterior hemiblock [LPH]) with a cardiac rate of thirty beats per minute, for which a temporary pacemaker was inserted. Endomyocardial biopsy showed histopathologic signs of myocarditis and the immunologic study of the cardiac tissue revealed positive polymerize chain reaction (PCR+) with the presence of antitoxine choleric antibodies (AcTCA). After three weeks, the same conduction disturbances remained, for which a permanent pacemaker was inserted. On top of intravenous fluid replacement and electrolyte supplements, the patient was managed with tetracycline 2 g a day for one week and sulfamethoxazole-trimethoprim 800/160 mg a day for two weeks. The purpose of this study is to present a rare and very well-documented myocarditis by cholera in a patient with enteric disease, in whom several cardiac complications occurred.

Anti-Bacterial Agents↗
PubMed1997

[Stress test in the elderly. Clinical, hemodynamic, metabolic and electrocardiographic variables].

PURPOSE: To identify in the elderly adaptations imposed by exercise in both sexes. METHODS: 1528 stress tests were performed on subjects divided in: group I (GI) (90%) between 65 to 75 years old, and group II (GII) more than 75 years old. Protocols applied were Bruce (72%), and modified Naughton (28%). Clinical, hemodynamic and electrocardiographic variables were estimated as recommended by the World Health Organization, and the metabolic variables in the adapted Naughton protocols by the American College of Sports Medicine standards. RESULTS: Analysis of GI and GII, respectively disclosed: 1) stress electrocardiogram (ECG): normal, 36 and 35%; ST depression, 20 and 22%; ST elevation, 6 and 1%; ventricular ectopic beats, 11 and 14%; supra ventricular ectopic beats, 5 and 6%; 2) metabolic and hemodynamic variables: the double-product: 26636 (+/-1539) and 23133 (+/-3218) mmHg X bpm (p < 0.0001). Maximum oxygen uptake measured in METS: GI, men, 7.7 (+/-1.9), women 5.4 (+/-0.8) (p < 0.0001); GII, NS, curve of systolic blood pressure: GI, men, 8.4 +/- (0.5), women, 10.6 (+/-1.8) mmHg/Met (p = 0.03); GII- NS. Difference of diastolic blood pressure and heart rate during exercise were similar between the two groups; 3) chest pain was the main clinical variable. CONCLUSION: The more frequent indication for stress testing to evaluate chest pain in GI, did not correspond to a predominance of this symptom in this group, during exercise; in GI, in contrast to what is seen in the young, the curve of systolic blood pressure was greater in women; despite the greater prevalence of coronary artery disease in aged subjects, it was not observed significative differences between the two groups, to ischaemic ST depression.

Aged↗
PubMed1997

[Morphological and functional correlations of the protective action of pantothenic acid in cisplatin ototoxicity (I)].

The protective effect of pantothenic acid and coenzyme A on cisplatin-induced ototoxicity in guinea pigs has been demonstrated. We studied the possible correspondence between functional disturbances studied by electrocochleography, specifically the latency of the N1 wave and morphological abnormalities on scanning electron microscopy. Statistical analysis showed no correspondence.

Animals↗
PubMed1996

Topographic distribution of CD18 integrin on human neutrophils as related to shape changes and movement induced by chemotactic peptide and phorbol esters.

The acquisition of high-affinity ligand binding may result from a topographical redistribution of beta2 integrins (CD11/CD18) in the plane of the membrane in response to agonist-induced neutrophil stimulation. We examined the topographical distribution of CD18 on human neutrophils in relation with shapes changes and movements induced by stimulation with 10(-8) M N-formylmethionyl-leucyl-phenylalanine (fMLP) and 10(-7) M phorbol myristate acetate (PMA). To localize CD18, we used immunogold-labeling methods and backscattered electron images obtained with scanning electron microscopy. On unstimulated neutrophils, CD18 integrin was randomly distributed on the nonvillous planar cell body. Stimulation of neutrophils with 10(-8) M fMLP and 10(-7) M PMA for 10 min induced distinctive shape changes, i.e., polar and nonpolar ruffled shapes, and upregulation of the surface membrane content of CD18. These changes were accompanied by a specific topographic distribution of CD18. fMLP-stimulated (10(-8) M) cells accumulated CD18 on the ruffled plasma membrane at the frontal pole of polar neutrophils. PMA-stimulated (10(-7) M) cells displayed CD18 aggregates on all plasma membrane domains, mainly on ruffles of nonpolar ruffled neutrophils. We conclude that the motile neutrophil responses elicited by chemotactic peptide and phorbol ester are associated with distinct patterns of topographic distribution of CD18 integrin. These features of CD18 expression may influence adhesive interactions mediated by human neutrophils.

CD18 Antigens↗
PubMed1996

Flagellar genes from Rhodobacter sphaeroides are homologous to genes of the fliF operon of Salmonella typhimurium and to the type-III secretion system.

A flagellar region of the genome of Rhodobacter sphaeroides was cloned and sequenced. Three ORFs were identified and arranged in the same order as fliH, fliI and fliJ of Salmonella typhimurium (St). ORF2 is highly similar to FliI from St (49% similarity) showing Walker's A and B motifs. Similar scores were found with proteins of the type-III secretion system of virulence factors. ORF3 shows 16.4 and 11.1% similarity to FliJ from St and Bacillus subtilis, respectively. This work also shows that ORF3 is similar to HrpJ5 from Pseudomonas syringae (19.2% similarity). It was found that ORF2 and ORF3 start immediately downstream from the adjacent coding region, suggesting a single transcriptional unit.

Amino Acid Sequence↗
PubMed1996

Evolutionary biology of parasitic platyhelminths: The role of molecular phylogenetics.

As our appreciation of the diversity within the flatworms has grown, so too has our curiosity about the ways in which these varied creatures are related to one another. In particular, the parasitic groups (trematodes, cestodes and monogeneans have been the focus of enquiry. Until recently, morphology, anatomy and life histories have provided the raw data for building hypotheses on relationships. Now, ultrastructural evidence, and most recently, molecular data from nucleic acid sequences, have been brought to bear on the topic. Here, David Blair, Andrés Campos, Michael Cummings and Juan Pedro Laclette discuss the ways in which molecular data, in particular, are helping us recognize the various lineages of flatworms.

Journal Article↗
PubMed1996

Pantothenic acid and coenzyme A in experimental cisplatin-induced ototoxia.

We have observed that pantothenic acid (PA) prevents deafness induced by cisplatin (CP) in the guinea pig if both drugs are administered jointly. When deafness was previously produced, recovery was sometimes obtained after the administration of PA; so, we studied the effects of PA on cisplatian-induced ototoxia in guinea pigs, both as a prophylactic agent in healthy animals, and as a therapeutic agent in animals previously made deaf by the drug. To elucidate why PA protects the ear from the toxic effects of CP, we used coenzyme A (CoA) instead of PA-since PA is a component of CoA-to test the hypothesis that the action of PA is due to CoA. The results were practically the same in both experiences, the compound action potential of the auditory nerve (CAP) was tested and cochleas were examined by scanning electron microscopy (SEM). Our results suggest that the protective effect of PA takes place through CoA. Both substances had the same effect on CP ototoxicity, but CoA appears to be much more active, since the dose tested here was much lower than that of PA.

Animals↗
PubMed1996

Cholesterol granuloma of the middle ear: report of 5 cases.

Cholesterol granulomas of the middle ear (CGME) constitute a focal inflammatory response with foreign body giant cells mobilized against the presence of cholesterol crystals. The air spaces within the temporal bone are commonly affected, especially in association with chronic disease of the middle ear involving diminished ventilation. The aim of this paper is to review 5 cases of CGME. The authors intend to establish the etiology of CGME and its likely relationship with other common middle ear diseases.

Adolescent↗
PubMed1996

Invasive fungal sinusitis in immunosuppressed patients. Report of three cases.

Report of three cases. Newly appeared immunosuppression related conditions have led to an increase in morbidity of systemic opportunistic mycoses. Rhinosinusal infection has also increased in frequency. Three invasive nasosinusal mycoses are presented: two cases of mucormycosis and a simultaneous infection by mucormycosis and candida albicans. In all cases, and despite treatment, progression of the disease could not be stopped and the patients died. The main characteristics of invasive nasosinusal mycoses are reviewed, to obtain early diagnosis. Early therapy improves the prognosis, and thus clinical suspicion justifies treatment before establishing a microbiological diagnosis.

AIDS-Related Opportunistic Infections↗
PubMed1996

Synthesis and processing of glypican during differentiation of skeletal muscle cells.

We identified previously a glycosylphosphatidylinositol (GPI)-anchored heparan sulfate proteoglycan (HSPG) releasable by phosphatidylinositol-specific phospholipase C (PI-PLC) on the surface of differentiated skeletal muscle cells (Campos et al., Eur. J. Biochem. 216, 587-595 (1993)) which is homologous to the HSPG synthesized by fibroblasts and Schwann cells called glypican. In this study we have evaluated the processing, location and amount of this HSPG in skeletal muscle cells during differentiation. Immunoprecipitation of incubation medium obtained from differentiated cells incubated with [35S]sulfate by specific antibodies against glypican isolated from Schwann cells demonstrated that the antisera precipitated an intact HSPG. Immunoblot analysis of the proteins released by PI-PLC after heparitinase treatment revealed the presence of a main band of 64 and a faint band of 62 kDa, whereas the sizes of the core proteins for glypican present in the incubation media were 62 and 59 kDa. Pulse-chase experiments indicated that glypican present in the membrane was spontaneously released into the culture medium with a t1/2 of 12 h. The level of expression of glypican was analyzed during in vitro differentiation. The specific amount of the PI-PLC releasable HSPG increased about fourfold during cell differentiation. No changes were detected in the level of the mRNA for glypican. Indirect analysis revealed that in myotubes glypican is present on the cell surface as well as associated with the extracellular matrix (ECM). These results indicate that glypican is present, at least, in two different compartments on the surface of skeletal muscle cells.

Animals↗
PubMed1996

Non-Hodgkin's lymphoma of the head and neck in association with HIV infection.

People infected with HIV have a greater risk of developing malignancies. The most frequent one is the Kaposi's sarcoma (KS). The second is the Non-Hodgkin's lymphoma (NHL). We report six cases of NHL in association with HIV infection (NHL-HIV) of the head and neck. Three of them had extranodal location (2 oral lymphomas and one case affecting the maxillary sinus). The other 3 cases were located in the cervical nodes. The oral malignancies were treated with radiotherapy (RT). Chemotherapy was applied to the other 4. Only one of our patients has survived more than two years. In one case the NHL was the first manifestation of the infection with HIV. Diagnosis of extranodal NHL requires search for AIDS.

Adult↗