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Biomedical subjects

M C Campos

Publications and source records attributed to M C Campos.

11 recordsLinked to original sources
PubMed2002

Tumor necrosis factor-alpha and interleukin-1beta mediate the production of nitric oxide involved in the pathogenesis of ifosfamide induced hemorrhagic cystitis in mice.

PURPOSE: We investigated the participation of nitric oxide in ifosfamide induced hemorrhagic cystitis in mice, and the involvement of tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta in the induction of nitric oxide production in this model. MATERIALS AND METHODS: Hemorrhagic cystitis was induced in mice by 100 to 400 mg./kg. ifosfamide and evaluated 6, 12, 24 or 48 hours thereafter by certain parameters, including vesical edema measurements, microscopic analysis and immunohistochemical testing for inducible nitric oxide synthase. Ifosfamide injected mice were pretreated with 10 to 40 mg./kg. of the nitric oxide synthesis inhibitor L-NG-nitroarginine methyl ester, 80 mg./kg. of mesna, a chemical antagonist of acrolein and the urotoxic metabolite of ifosfamide, 50 microl. antiserum against TNF-alpha and IL-1beta per mouse, 45 mg./kg. of the selective TNF-alpha synthesis inhibitor thalidomide or 200 mg./kg. of the TNF-alpha and IL-1beta synthesis inhibitor pentoxifylline. RESULTS: Ifosfamide induced vesical edema, which peaked 12 hours after ifosfamide injection. Microscopic analysis revealed vascular congestion, edema, hemorrhage, fibrin deposition, neutrophil infiltration and epithelial denudation. Inducible nitric oxide synthase immunolocalization demonstrated intense reactivity to inducible nitric oxide synthase in the cytoplasm of bladder epithelial cells, which showed diffuse necrosis. Pretreatment with mesna reduced the increases in vesical edema, while treatment with L-NG-nitroarginine methyl ester, antiserum to TNF-alpha or IL-1beta, thalidomide or pentoxifylline inhibited vesical edema and microscopic alterations. Antiserum treatments also inhibited the expression of inducible nitric oxide synthase in the urothelium. CONCLUSIONS: Nitric oxide produced by inducible nitric oxide synthase is involved in urothelial damage and in the inflammatory events leading to hemorrhagic cystitis after ifosfamide administration in mice. The induction of inducible nitric oxide synthase in the urothelium appears to depend on the synergistic effect of IL-1beta and TNF-alpha.

Animals↗
PubMed2001

Intelligent system for start-up of a petroleum offshore platform.

It is difficult to control and to manage the start-up of a petroleum offshore platform. In order to solve this problem an intelligent system can play an important role, since available qualitative operator and design knowledge can be easily implemented to assist the operator during start-up. This paper describes the integration of an expert system with a fuzzy controller applied to such a process. The intelligent system has many heuristic rules to implement the automation of the start-up procedures, like the opening of many on-off valves while simultaneously monitoring process variables. It also has a fuzzy controller to optimize the opening of the oil wells, in order to minimize the start-up time. This intelligent system is being implemented in the platform P-19 of Petrobras, the Brazilian oil company, in Campos Basin, Brazil. The prototype has been operating since October 1998.

Journal Article↗
PubMed2000

Oral ciprofloxacin vs. intravenous ceftriaxone administered in an outpatient setting for fever and neutropenia in low-risk pediatric oncology patients: randomized prospective trial.

BACKGROUND: Infections are one of the major complications in children undergoing chemotherapy. Monotherapy with either ciprofloxacin or ceftriaxone is safe and efficient in low-risk patients (solid tumors and stage I/II lymphomas). The same drugs may be used in an outpatient setting, decreasing costs and the risk of nosocomial infections. PROCEDURE: Low-risk patients (N = 70) with episodes of fever and neutropenia (N = 116) were randomized to receive either oral ciprofloxacin or intravenous ceftriaxone as outpatients. Only one patient had a central venous catheter. RESULTS: Episodes of fever and neutropenia were classified as fever of unknown origin (41% vs. 32%) or clinically documented infection (56% vs. 63%) in the ciprofloxacin and ceftriaxone groups, respectively. Most of these infections were of upper respiratory tract, skin, or gastrointestinal origin. The mean duration of neutropenia was 5 vs. 6 days. Fever persisted for 1-9 days (mean 2 vs. 3 days). Therapy was successful with no modifications in 83% vs. 75% of the episodes. Patients were admitted in 7% vs. 4% of the episodes. No bone or joint side effects were seen in either group. All patients survived. CONCLUSIONS: Outpatient therapy with either oral ciprofloxacin or intravenous ceftriaxone for fever and neutropenia is effective and safe in pediatric patients with solid tumors and stage I/II non-Hodgkin lymphoma (low-risk patients).

Administration, Oral↗
PubMed1997

Role of microtubules and microtubule organizing centers on meiotic chromosome elimination in Sciara ocellaris.

Spindle formation and chromosome elimination during male meiosis in Sciara ocellaris (Diptera, Sciaridae) has been studied by immunofluorescence techniques. During meiosis I a monopolar spindle is formed from a single polar complex (centrosome-like structure). This single centrosomal structure persists during meiosis II and is responsible for the non-disjunction of the maternal X chromatids. During meiosis I and II non-spindle microtubules are assembled in the cytoplasmic bud regions of the spermatocytes. The chromosomes undergoing elimination during both meiotic divisions are segregated to the bud region where they associate with bundles of microtubules. The presence and distribution of centrosomal antigens in S. ocellaris meiotic spindles and bud regions has been investigated using different antibodies. gamma-Tubulin and centrin are present in the bud as well as in the single polar complex of first meiotic spindle. The results suggest that spermatocyte bud regions contain microtubule-organizing centres (MTOCs) that nucleate cytoplasmic microtubules that are involved in capturing chromosomes in the bud regions. The distribution of actin and myosin in the spermatocytes during meiosis is also reported.

Actins↗
PubMed1993

Paternity testing with the F10 multilocus DNA fingerprinting probe.

Empirical analysis of 200 paternity cases by multilocus DNA fingerprinting with the F10 probe showed that it was capable of distinguishing fathers from non-fathers in every case. The average exclusion probability was 0.99998. A very effective discrimination parameter was the proportion of non-maternal (test) bands which cannot be detected in the alleged father (unassignable bands) among all test bands. Values below 0.2 were seen in true fathers while in all cases of non-fathers the values were above 0.35. Minisatellite mutations occurred at a rate of 0.004 per band per child. The distribution of band-sharing among first degree relatives and unrelated individuals showed only a small overlap. Thus, band-sharing of the F10 fingerprints should provide a useful statistic for testing genetic relationships in deficiency cases.

Base Sequence↗
PubMed1992

Methotrexate hepatotoxicity in psoriatic patients submitted to long-term therapy.

Eighty-four patients with severe psoriasis who required methotrexate (MTX) therapy have been reviewed. A total of 134 liver biopsies were performed. The lack of correlation between alcohol intake and the use of potential hepatotoxic drugs with pretreatment liver biopsies is noted. A review of 30 patients who had liver biopsies performed before and after MTX treatment showed no statistically significant difference between the histological grades before and after treatment. Nor was there any absolute correlation between the cumulative MTX doses and the histological changes of follow-up biopsies. In this group of patients, 15 (50%) developed fibrosis, which was severe in 2 patients, after 3,431 mg MTX average dose. Cirrhosis was observed in 3 patients (10%) after 1,667 mg MTX average dose. Follow-up liver biopsies are recommended for patients treated with MTX.

Adolescent↗
PubMed1992

[Not Available].

Explore the source record for details and available documents.

Brazil↗
PubMed1980

An improved electrophoretic method for a screening program for haemoglobinopathies.

A method for a screening program for haemoglobinopathies in a starch agar gel mixed with saponin is presented. Normal and abnormal blood containing haemoglobins S, C, I, M Boston, D Punjab, beta thalassaemia major and beta thalassaemia minor, were applied, in a tray with the capacity for 100 samples. The electrophoresis was performed in 45 min using 300 V. This method offers special advantages for the examination of a large number of samples, using a small amount of whole blood and without the previous preparation of haemoglobin solution.

Electrophoresis, Agar Gel↗
PubMedDate not supplied

Expression and isoforms of gp43 in different strains of Paracoccidioides brasiliensis.

Individual exoantigens from 13 Paracoccidioides brasiliensis isolates were obtained and tested against a panel of 50 sera from patients with paracoccidioidomycosis by immunodiffusion test. The index of positivity varied from 20 to 100% according to the isolate. When these exoantigens were analysed by SDS-PAGE, eight presented high amounts of the glycoprotein gp43, two presented small amounts and in three there was no detectable gp43. The eight isolates presenting high amounts of gp43 were submitted to isoelectric focusing, blotted to nitrocellulose membranes, and revealed by monoclonal and polyclonal anti-gp43 antibodies. Four gp43 isoform profiles were obtained: profile A presenting pIs of 6.0, 6.2, 6.6 and 7.0, profile B presenting pIs of 6.4, 6.8 and 7.2, profile C presenting pI > 8.5 and profile D, presenting pIs of 5.8, 6.2 and 6.6. In each pattern observed, a major band with a distinct pI was detected. Despite this variation, our results strongly suggest an epitopic conservation among all isoforms analysed, since all of them were recognized by anti-gp43 monoclonal antibodies.

Antibodies, Monoclonal↗