Browsing by Author "GUTIERREZ, M"

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    ANTICARDIOLIPIN ANTIBODIES IN ACUTE RHEUMATIC-FEVER
    (J RHEUMATOL PUBL CO, 1992) FIGUEROA, F; BERRIOS, X; GUTIERREZ, M; CARRION, F; GOYCOLEA, JP; RIEDEL, I; JACOBELLI, S
    Recent reports describe the association of antiphospholipid antibodies (aPL) with chorea or severe heart valve lesions in systemic lupus erythematosus, lupus-like disease, or the primary antiphospholipid antibody syndrome. We conducted a case series and a case-control investigation of patients with rheumatic fever with Sydenham chorea or other manifestations of rheumatic fever for anticardiolipin antibodies (aCL) during the acute attack and disease remission. Eighty percent of patients were positive for aCL during the rheumatic fever attack vs 40% when inactive (p = 0.035); IgG and IgM aCL increased significantly with disease activity. Individuals with or without Sydenham chorea were equally positive for aCL (76 and 83%, respectively). A significant association was found between IgM aCL and carditis: All patients with valvulitis had IgM aCL (100%) vs 37% of patients without valvular involvement (p = 0.02). aPL may play a role in the pathogenesis of some clinical manifestations of acute rheumatic fever.
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    RADICAL SCAVENGING IN THE SONOLYSIS OF AQUEOUS-SOLUTIONS OF I-, BR-, AND N3-
    (AMER CHEMICAL SOC, 1991) GUTIERREZ, M; HENGLEIN, A; IBANEZ, F
    Iodide and bromide solutions are sonolyzed under pH conditions, where reactions of the products, i.e. hydrogen peroxide and iodine (or bromine), do not occur. The total yield of the products as well as the hydrogen yield is independent of solute concentration. The results are understood in terms of the competition of the OH + OH and the OH + solute reactions. A local concentration of 4 x 10(-3) M of the OH radicals in an interfacial region between the cavitation bubbles and the liquid is derived from the data obtained. The sonolysis of azide solutions is also investigated. The main product is nitrogen, which is formed in the reaction of N3- with OH radicals in the millimolar concentration range. At higher azide concentrations, additional nitrogen is formed as hydrogen atoms are also scavenged. Ammonia and hydrazine are minor products of the N3- sonolysis.
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    VENTILATORY DRIVE AND RESPIRATORY MUSCLE FUNCTION IN PREGNANCY
    (AMER LUNG ASSOC, 1991) CONTRERAS, G; GUTIERREZ, M; BEROIZA, T; FANTIN, A; ODDO, H; VILLARROEL, L; CRUZ, E; LISBOA, C
    It has been demonstrated that during pregnancy expiratory reserve volume (ERV) decreases and minute ventilation (VE) increases initially and then stabilizes. In order to determine the role of thoracoabdominal mechanics, control of breathing, and inspiratory muscle function in these alterations, we studied inspiratory pressures, lung volumes, thoracic configuration, and respiratory drive in 18 normal pregnant women at Weeks 13, 21, 30, and 37 of pregnancy. Ten of them were studied 6 months after delivery. Transdiaphragmatic pressure (Pdi) was measured at Week 37 and 3 months after delivery in an additional group of seven women. VE as well as VT/Tl increased early during gestation and remained unchanged thereafter. In contrast, mouth occlusion pressure (P0.1) increased progressively during pregnancy, from 1.53 +/- 0.16 (mean +/- SE) to 2.02 +/- 0.18 cm H2O, and fell significantly to 1.1 +/- 0.15 cm H2O after delivery, indicating that effective respiratory impedance increases during pregnancy. Mean P0.1 correlated with progesterone plasma levels (r = 0.918 p < 0.05). No changes in Plmax, PEmax, and Pdi(max), were observed. End-expiratory gastric pressure (Pga) increases significantly during pregnancy: 11.8 +/- 0.8 versus 8.4 +/- 1.12 cm H2O after delivery (p < 0.012). This increment was correlated with the fall in ERV observed in late pregnancy (r = 0.74 p < 0.05). Our results demonstrate that during pregnancy ventilatory drive and respiratory impedance increase with the consequent stabilization of VE, but our data do not permit us to differentiate whether the increment in P0.1 is secondary to the increase in impedance or to the rise in progesterone. Respiratory muscle function remains normal despite the alteration of thoracic configuration.
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    WEEKLY CUIRASS VENTILATION IMPROVES BLOOD-GASES AND INSPIRATORY MUSCLE STRENGTH IN PATIENTS WITH CHRONIC AIR-FLOW LIMITATION AND HYPERCARBIA
    (1988) GUTIERREZ, M; BEROIZA, T; CONTRERAS, G; DIAZ, O; CRUZ, E; MORENO, R; LISBOA, C
    We studied the effects of an 8-h, once-a-week schedule of cuirass ventilation (CV) in 5 patients with advanced chronic air-flow limitation and chronic hypercarbia (PaCO2, 58.6 .+-. 10.1 mm Hg; mean .+-. SD). Repeated measurements of arterial blood gases, maximal inspiratory mouth pressure (Pimax), 12-min walking distance, and respiratory cycle were performed during a 1-mouth run-in period. Quality of life and transdiaphragmatic pressure were measured once. All patients completed the planned 4-month study. Four of them were ventilated for longer periods because CV could not be discontinued at the end of the study. PaCO2 showed a significant fall starting during the first month; PaO2 significantly increased from the second month, whereas Pimax significantly rose from the third month on. Maximal trnsdiaphragmatic pressure increased in the 2 patients with abnormal baseline values. The fall in PaCO2 was associated with an increase in tidal volume because of a longer inspiratory time. Significant improvements in quality of life and in the 12-min walking distance were observed. We conclude that weekly CV improves blood gases, inspiratory muscle strength, and clinical conditions of patients with chronic air-flow limitation and chronic hypercarbia, probably because of correction of chronic inspiratory muscle fatigue.