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V Plaza

Publications and source records attributed to V Plaza.

15 recordsLinked to original sources
PubMed1992

Platelet kinetics in asthmatic patients with and without aspirin intolerance.

BACKGROUND: A reduced platelet survival time has been described in asthmatic patients. There is also good evidence that platelets are involved in aspirin induced asthma. Since aspirin intolerant patients usually suffer from an active disease and often require anti-inflammatory treatment, it has been suggested that platelet survival time may be shorter in aspirin intolerant asthmatic subjects than in aspirin tolerant subjects. The objective of this study was to investigate this hypothesis. METHODS: Thirteen asthmatic subjects (six aspirin tolerant and seven aspirin intolerant) in a stable clinical condition and ten healthy subjects were studied. Platelet kinetics and survival time were measured with indium-111 labelled autologous platelets. RESULTS: Mean (SD) platelet sequestration ratios in the spleen and liver were lower in asthmatic (2.3 (0.9) and 0.6 (0.2) respectively) than in healthy subjects (3.2 (0.7) and 1.1 (0.4) respectively). However, mean (SD) platelet survival time in asthmatic subjects (8 (2.7) days) did not differ from that in healthy subjects (7.6 (1.1) days). No differences were observed in platelet kinetics between aspirin tolerant and aspirin intolerant patients. CONCLUSIONS: These results suggest the existence of an active non-splenic pool of platelets in patients with asthma. However, they failed to show platelet kinetic differences among asthmatic subjects with and without aspirin intolerance and do not support previous studies suggesting an altered platelet survival in stable asthma.

Adult↗
PubMed1992

Release of peptide leukotriene into nasal secretions after local instillation of aspirin in aspirin-sensitive asthmatic patients.

Although the mechanism of aspirin-induced asthma and rhinitis is unknown, it has been suggested that adverse nasal and bronchial reactions are caused by an increased production of lipoxygenase products. In examining this hypothesis we have measured the release of peptide leukotrienes (PeptLTs), 15-HETE, and prostaglandins in nasal fluids obtained by nasal lavages after instillation of acetylsalycilic acid (ASA) and placebo (saline). Ten ASA-sensitive asthmatics, 10 ASA-insensitive asthmatics, and seven healthy subjects were challenged in a double-blind study with normal saline and 12 mg of ASA. Twelve mg were administered based on the results of a previous study that showed that this dose caused minor to moderate symptoms in ASA-sensitive patients. PeptLTs, LTB4, 15-HETE, PGE2, PGF2 alpha, and PGD2 were measured by radioimmunoassay methods. Significant levels of PeptLTs were detected in sensitive asthmatic patients 60 min after nasal challenge. This change was associated with a significant increase in symptoms. No increase in PeptLTs levels were found, however, in either insensitive patients or healthy subjects. Inhibition of PGE2 and PGF2 alpha release was detected in the three groups after ASA administration. ASA also inhibited PGD2 release in insensitive asthmatic patients but not in both sensitive patients and healthy subjects. These results suggest that an abnormal release of PeptLTs in ASA-sensitive asthmatic patients contributes to nasal and bronchial adverse reactions. The lack of effects on PGD2 release suggests that mast cells from ASA-insensitive patients are more sensitive to ASA than those from sensitive asthmatic patients and healthy subjects.

Administration, Intranasal↗
PubMed1991

[Kidney failure, acute hepatitis and rhabdomyolysis secondary to an acute cytomegalovirus infection in a previously healthy patient].

A 40-year-old male with unremarkable past history was admitted because of fainting during an athletic run in the city. At the time of admission there were increased plasma creatinine level and phosphokinase activity, with myoglobinuria and increased transaminase activity. Serologic tests for viruses on admission and after 15 days showed a selective increase in the anti-CMV titer from 1/16 to 1/256, being negative for the remaining viruses. The renal function rapidly recovered without sequelae. According to the literature, this would be the first reported case of acute renal failure, rhabdomyolysis and acute hepatitis due to cytomegalovirus infection in a previously healthy individual.

Acute Disease↗
PubMed1991

Effect of negative pressure ventilation on arterial blood gas pressures and inspiratory muscle strength during an exacerbation of chronic obstructive lung disease.

The effects of intermittent negative pressure ventilation have been studied in 20 patients with chronic obstructive pulmonary disease during an exacerbation of their disease. Measurements of arterial blood gas tensions and maximal inspiratory pressure (MIP) were performed before and after six hours of negative pressure ventilation or standard treatment (control day) given in random order on two consecutive days. After negative pressure ventilation the mean (SD) value of MIP increased from 68.1 (21.5) to 74.8 (20) cm H2O;* arterial oxygen tension (PaCO2) fell from 60.6 (12.2) to 50.9 (8.9) mm Hg* but PaO2 changed little (from 48.4 (7.4) to 47.6 (8.2) mm Hg). There were no significant changes on the control day in arterial blood gas tensions (PaO2 47.8 (8.1) and 48.9 (9.4) and Paco2 59.8 (10.9) and 57.5 (8.06) mm Hg) or in MIP (69.4 (22.4) and 70.9 (22.9) cm H2O). Six patients tolerated negative pressure ventilation poorly and these patients showed less improvement after negative pressure ventilation. Our results suggest that intermittent negative pressure ventilation can increase alveolar ventilation in patients with an exacerbation of chronic obstructive lung disease, particularly in those who tolerate the procedure well. Most subjects showed a fall in PaCO2 and an increase in MIP. The fact that PaO2 was unchanged despite the fall in PaCO2 suggests that gas exchange may deteriorate with negative pressure ventilation in these patients.

Aged↗
PubMed1989

[High-degree malignancy non-Hodgkin's lymphoma simulating a disseminated carcinoma. Presentation of 2 cases].

Highly malignant non-Hodgkin lymphomas (HM-NHL) may sometimes develop clinical features simulating an epithelial carcinoma with metastatic dissemination. Conventional histopathological study may be insufficient to differentiate between both conditions. Two patients with HM-NHL are reported with a rapid general deterioration; one of them had osteolysis and hypercalcemia. In both cases a diffuse bone marrow infiltration by large sized cells with blastic appearance was found. The initial suspected diagnosis was occult epithelial neoplasia with metastatic dissemination. The morphological study with optic microscopy and the ultrastructural analysis did not establish the origin of these cells. The definitive diagnosis was obtained by immunohistochemical techniques. In both cases, the cells were positive for the CD 45 (common leukocyte antigen) monoclonal antibody (MoAb), and for several MoAbs of lymphoid B differentiation. In one of them, the B lymphoid lineage was confirmed by monoclonal reordering of the gene that synthetises the immunoglobulin heavy chain.

Aged↗
PubMed1989

Bronchoalveolar lavage cell analysis in patients with human immunodeficiency virus related diseases.

The value of differential cell counts in bronchoalveolar lavage fluid in patients who were serologically positive for the human immunodeficiency virus (HIV) was studied in 30 patients with classified into four groups according to the severity of illness: (1) seven subjects with the AIDS related complex without clinical or radiological evidence of pulmonary infection; (2) eight patients with the AIDS related complex and pulmonary tuberculosis; (3) eight patients with AIDS and Pneumocystis carinii pneumonia; and (4) seven patients with AIDS, Pneumocystis carinii pneumonia, and severe respiratory failure. All four groups had a similar percentage of lymphocytes, significantly higher than that of a control group of 15 healthy volunteers. A significant increase in the percentage of neutrophils was observed in groups 2, 3, and 4. The lavage fluid differential cell count does not therefore appear to help in the differential diagnosis of pulmonary infections in HIV positive patients. The abnormal percentage of lymphocytes observed in some patients with the AIDS related complex without clinical evidence of pulmonary infection suggests that lung injury may exist before clinical or radiological abnormalities develop. This might be related to an immunological mechanism or might be caused by an undetected subclinical infection.

AIDS-Related Complex↗
PubMed1989

How many manoeuvres should be done to measure maximal inspiratory mouth pressure in patients with chronic airflow obstruction?

To determine the number of maximal mouth pressure manoeuvres needed to obtain a reproducible value of maximal inspiratory mouth pressure (MIP), we studied 44 patients with chronic airflow obstruction, with a mean (SD) % predicted FEV1 value of 53.9 (25), who were clinically stable. Maximal inspiratory mouth pressure was determined with an anaeroid manometer during maximal inspiratory efforts in a quasi static condition at residual volume. All patients performed 20 consecutive maximal inspiratory mouth manoeuvres, each one separated by 30-40 seconds. The mean (SD) values of MIP varied from 71.5 (25.5) cm H2O at the first measurement to 80.1 (27) cm H2O at the last measurement. Maximal values of MIP were usually achieved after nine determinations. It is concluded that to obtain a reproducible MIP value in patients with chronic airflow obstruction who are untrained and unexperienced in such manoeuvres a minimum of nine technically acceptable maximal mouth pressure manoeuvres should be performed.

Female↗
PubMed1989

Predisposing factors to death after recovery from a life-threatening asthmatic attack.

The outcome of 49 asthmatics (20 men and 29 women) who had suffered a severe exacerbation of asthma requiring mechanical ventilation was investigated in a follow-up study ranging from 23 weeks to 10 years. Over this time, there were 6 fatalities, all female chronic asthmatics requiring treatment with bronchodilators, beclomethasone, and short courses of oral steroids. Three died at home as a consequence of a sudden attack. Another patient developed a cardiorespiratory arrest immediately after having received a sedative. In the remaining two cases, death occurred within hours or days of progressive deterioration. Four of the six women had required psychiatric treatment for an anxiety-depression syndrome. These findings support previous studies suggesting that psychological disturbances may be predisposing factors to death in bronchial asthma.

Aged↗
PubMed1986

Unusual metastatic chondrosarcoma detected with bone scintigraphy.

A case is presented of a scapular chondrosarcoma which showed intense uptake of Tc99m MDP in the primary tumour and in pleural and osseous metastases. Additionally, there was intense visualization of the malignant pleural effusion. The bone scintigraphy correctly diagnosed the extent of the involvement. This finding is unusual because chondrosarcomas in such a disseminated state are relatively rare.

Aged↗