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Biomedical subjects

M Navarro

Publications and source records attributed to M Navarro.

At least 361 records · Page 20Linked to original sources
PubMedDate not supplied

Determination of arsenic in fish by hydride generation atomic absorption spectrometry.

A method utilizing microwave dissolution in a closed Teflon bomb followed by hydride generation atomic absorption spectrometry has been used for the routine analysis of arsenic in fish species from the coast of the province of Granada, Spain. The technique was evaluated for decomposing biological standard reference material (BCR mussel tissue) for arsenic analyses. The precision of the results ranged from 2.78 to 6.99%. The recovery percentages ranged from 96.33 to 100.00%. The values determined in the samples indicated slight contamination by this element in the zone. The concentrations of arsenic in fish ranged from 0.396 to 45.716 micrograms/g.

Animals↗
PubMedDate not supplied

Immunorestorative effect of thymostimulin on surgery immunodepression: experimental model.

The purpose of the present study is to ascertain the immunorestorative effect of two different drugs on immunodepression induced by small bowel surgical resection in an experimental model. The potential immunorestorative effect has been measured by the ability of the drug to avoid the delay of skin allograft rejection induced by surgery and the inhibition of CD4/CD8 index changes induced by surgery in spleen tissue. 120 Wistar-Furth rats (age 12-16 weeks) anesthetized with a single intramuscular dose of ketamine (25 mg), diazepine (4 mg) and atropine (0.1 mg) were allotted to two main groups. One group received a skin graft (SG) from Fisher 344 rats and was treated with placebo, Inmunoferón (AM-3 polypeptidic drug) or TP-1 (thymostimulin) before the experiment (groups I, II, III) or treated with placebo, Inmunoferón or TP-1 before the experiment and underwent enterectomy and anastomosis (groups IV, V, VI). On the 2nd, 5th and 8th postoperative days, biopsies of the SG were taken and the signs of rejection were microscopically studied and evaluated by a pathologist as zero, incipient, moderate or massive. The other group was treated similarly, but the animals did not receive a SG and were splenectomized 5 days later. CD4 and CD8 lymphocyte subpopulations were identified by means of immunoperoxidase technique and monoclonal antibodies. Thymostimulin is able to stimulate the presence of SG rejection signs on the 2nd postoperative day in nonenterectomized animals and on the 8th postoperative day in nonenterectomized animals and on the 8th postoperative day in enterectomized rats and is able to avoid the decrease of the CD4/CD8 index in spleen tissue after surgical immunodepression.(ABSTRACT TRUNCATED AT 250 WORDS)

Adjuvants, Immunologic↗
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Retrospective evaluation of toxicity in three different schedules of adjuvant chemotherapy for patients with resected colorectal cancer. TTD Spanish Cooperative Group.

Adjuvant chemotherapy has been established since 1990 as standard treatment for patients with colon cancer stage III (Dukes' C). Chemotherapeutic schemes combining 5-fluorouracil with levamisole or leucovorin have shown significant advantage over surgery alone. Adjuvant trials are being currently implemented to investigate some relevant questions, such as which is the optimal duration of chemotherapy, as well as the possible advantage of levamisol versus leucovorin schedules, and of high-dose versus low-dose leucovorin. While these trials are ongoing, a retrospective evaluation of the toxicity associated with the different chemotherapeutic schemes might be of help when choosing the most appropriate regimen for individual patients not involved in clinical trials. A total of 519 patients subjected to three different schedules of adjuvant chemotherapy between 1993 and 1996, were evaluated for toxicity according to the NCI-CTC criteria. Chemotherapeutic regimens were: 5-fluorouracil plus levamisole (5-Fu+Lev; Moertel schedule), 5-fluorouracil plus low-dose leucovorin (5-Fu+LVLD; NCCTG schedule) and 5-fluorouracil plus high-dose leucovorin (5-Fu+LVHD; IMPACT-modified schedule). 5-Fu+LVLD is significantly more toxic than the other two regimens in terms of neutropenia, mucositis and diarrhea. delay in chemotherapy and dose reduction of 5-fluorouracil were also more frequent in the 5-Fu+LVLD group. However, the percentage of prematurely discontinued treatments was significantly higher in the 5-Fu+Lev group. Information on toxicity of adjuvant chemotherapy for colon cancer may help medical oncologists to choose the most appropriate regimen for individual patients not involved in clinical trials.

Adjuvants, Immunologic↗
PubMedDate not supplied

Primary polyarteritis nodosa presenting as acute symmetric quadriplegia.

We report a case of peripheral neuropathy presenting as acute symmetric areflexic quadriplegia in the setting of a well-defined clinical, histopathologic, and angiographic diagnosis of classic polyarteritis nodosa. While it is usually easy to recognize the typical clinical presentation of necrotizing angiopathy-induced peripheral neuropathy as a mononeuritis multiplex or a distal polyneuropathy in association with a collagen vascular disease, clinicians must be equally sensitive to a number of more challenging possibilities. Acute quadriplegia similar to that seen in Guillain-Barré syndrome can be secondary to primary classic polyarteritis nodosa and the former may be the chief or even the sole manifestation of the latter.

Aged↗
PubMedDate not supplied

[Multidrug-resistant Salmonella a significant clinical problem?].

The incidence of infections caused by Salmonella strains resistant to antibiotics, including ampicillin, chloramphenicol, streptomycin, sulfonamides, tetracycline and even amoxicyllin-clavulanate, is increasing. We present two cases that illustrate the potential severity of infections caused by multidrug-resistant Salmonella and also the difficulty of reaching a differential diagnosis with inflammatory bowel disease.

Adult↗
PubMedDate not supplied

Determination of lithium in human serum by electrothermal atomic absorption spectrometry.

An efficient method was developed for the determination of nanogram levels of lithium in biological samples. Serum samples from human subjects from southeastern Spain, treated or not treated with lithium carbonate, were analyzed by electrothermal atomic absorption spectrometry. The samples were previously treated with a matrix modifier consisting of 0.1% Triton X-100 and injected through a graphite tube with L'vov platform. The Li concentrations measured by the procedure described for the 3 certified reference samples used were not significantly different (p > 0.05) than certified levels. Sample recoveries and variability during several days, with coefficients of variation from 4.00 to 14.8%, demonstrated the reliability and accuracy of this technique. Mean Li concentration determined in the serum of individuals with psychiatric disorders treated with Li (n = 117, 5.077 +/- 1.795 microg Li/mL) was significantly higher (p < 0.001) than that in individuals not treated with Li (n = 24, 1.902 +/- 2.054 ng Li/mL).

Adult↗
PubMedDate not supplied

[Adjuvant chemotherapy of non-seminoma stage I germ cell tumors of the testis].

OBJECTIVE: To review the treatment of stage I nonseminomatous germ cell testicular tumor with adjuvant chemotherapy. METHODS: The literature on this subject was reviewed. RESULTS/CONCLUSIONS: Overall, 30% of stage I nonseminomatous germ cell testicular tumors that are followed recur within two subsequent years. Several factors associated with a higher risk have been described. The most important are the presence of venous or lymphatic infiltration, the presence of a carcinoembryonic component and the absence of tumor of the endodermal sinus. Patients with the foregoing characteristics have a recurrence rate of approximately 50%. Over the last few years, some experience using two cycles of BEP adjuvant chemotherapy in patients at a higher risk have shown that this recurrence rate can be reduced to less than 5% with minimal late toxicity.

Chemotherapy, Adjuvant↗
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[Urinary tract infection in early infancy, study of 15 cases].

Urinary tract infection in the newborn shows peculiar characteristics not found in older children. 15 cases of urinary tract infection in infants aged 7 days to 2 months are presented. There is higher incidence in males (11 m./4 f.). Severe clinical picture diverse and undefined clinical course, incidence of jaundice radiological findings and posterior evolution are specially noted. Early diagnosis and effective management lined in base to evolution and prognosis. Hospital stay varied between 2 and 12 weeks. No deaths were registered.

Age Factors↗
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[Natural history of urinary tract infection in children].

Urinary tract infection was studied in 61 children whose ages ranged between 6 months and 9 years. History, symptoms, urine cultures and renal function are compared between those with normal radiology and those with pyelonephritis and/or reflux and obstructive lesions. Prognosis was analized in these two groups.

Age Factors↗
PubMedDate not supplied

P300 component of the auditory event-related potentials and dyslexia.

Ten normal children (mean age = 9 years) and 12 dyslexic children (mean age = 8.1 years) were compared for latency, amplitude and topographic distribution of both parameters of P300. We found a significant increase in P300 latency in the dyslexic group. Noteworthy is the increase in amplitude in the central parietal area in the control group. These facts and their incidence are discussed in the present study.

Acoustic Stimulation↗
PubMedDate not supplied

Late thrombotic events in patients with temporal arteritis and anticardiolipin antibodies.

IgG and IgM isotypes of anticardiolipin (aCL) antibodies were measured in a group of 40 patients with biopsy-proven temporal arteritis (TA), 13 of them with ischemic complications related to the disease. High levels of aCL antibodies were found in only 3 (7.5%) patients. Two had high titres of both IgG and IgM isotypes and the third had high titres of the IgM isotype. No relationship between aCL antibody positivity and the development of any of the classical early occlusive complications of TA was found. However, 2 out of the 3 patients with positive aCL antibody titres later developed ischemic phenomena on conventional corticosteroid treatment. This finding suggests that aCL antibodies could perhaps have a role in the development of the late ischemic complications that occasionally occur in adequately treated TA patients.

Aged↗
PubMedDate not supplied

[The effect of preoperative parenteral nutrition on the capacity of the immune response in malnourished patients (preoperative parenteral nutrition and immunity)].

The objective of this study is to evaluate the response of the subpopulations of lymphocytes and IGs to the administration of total parenteral nutrition for 7 days in 26 patients suffering from malnutrition, 12 of whom had digestive neoplasia and 14 non-neoplastic gastrointestinal disorders. Following the total parenteral nutrition, a significant increase in the percentage of T-helper lymphocytes was noted, and an improvement in the OKT4/OKT8 quotient, as well as in the IgA and the C4 fraction of the complement. The existence of neoplastic conditions did not have a significant effect on the variations in the parameters studied. The presence of lipids in the parenteral nutrition diet did not affect the subpopulations of lymphocytes.

Antigen-Antibody Reactions↗
PubMedDate not supplied

CA 15.3: early results of a new breast cancer marker.

A new antigen associated with breast cancer, CA 15.3, was determined in the serum of 690 breast cancer patients and controls. After establishing a maximum normal level of 40 U/ml in 140 healthy subjects and 350 patients with benign diseases, CA 15.3 was investigated in 190 breast cancer patients: CA 15.3 serum levels were statistically different in patients with no evidence of disease (20.6 +/- 11.2 U/ml), metastatic patients in response (33.5 +/- 24.0 U/ml) and metastatic patients not responding to therapy (stable disease, 98.9 +/- 50.4; progression, greater than 200). CA 15.3 serum levels seem to correlate with the extent of metastatic breast cancer. Further studies are needed to establish the role of this marker in the management of breast cancer patients.

Antigens, Neoplasm↗
PubMedDate not supplied

Circulating CA 15.3 levels in breast cancer. Our present experience.

CA 15.3 is an antigen expressed by human breast carcinoma cells, and defined by two monoclonal antibodies, 115D8 and DF3. We used IRMA to determine the circulating serum levels of CA 15.3 in 1178 subjects with breast cancer, non-breast malignancies, benign diseases and controls. A threshold level of 40 U/ml was established with 140 healthy controls and 650 patients with benign diseases (respectively 0% subjects and 1.5% patients had abnormal antigen levels). Elevated CA 15.3 was found in 12 of 184 patients with malignancies different from breast cancer (6.5%), either epithelial carcinomas with distant metastases, mainly in the liver, or primary liver tumors. Breast cancer patients (n = 204) were analysed by prior therapy, UICC stage and WHO response to therapy. Eight of 134 (5.9%) patients with stage II or III breast cancer at presentation and no evidence of disease (NED) had elevated CA 15.3. All of 22 patients with stage IV breast cancer not responding to therapy (SD and PD) had antigen levels greater than 40 U/ml, as did 10 of 34 (29.4%) stage IV patients in objective response (CR + PR). Three of 14 pretreatment patients had abnormal marker levels, and they later proved to have distant metastases. Serum CA 15.3 values were statistically different (p less than 0.01) in NED (20.6 +/- 11.2 U/ml), CR + PR (33.5 +/- 24.0 U/ml), stable disease (98.8 +/- 50.4 U/ml) and progressive disease (greater than 200 U/ml) breast cancer patients. Our results suggest that circulating CA 15.3 antigen levels agree with the stage of breast cancer and with the response to therapy.

Adult↗