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61.
Alexandre T Rotta Mário Eduardo G Viana Budi Wiryawan Guilherme A Sargentelli Mark S Dowhy Walter A Zin Bradley P Fuhrman 《Pediatric critical care medicine》2006,7(6):562-570
OBJECTIVE: To evaluate the independent and combined effects of high-frequency oscillatory ventilation (HFOV) and partial liquid ventilation (PLV) on gas exchange, pulmonary histopathology, inflammation, and oxidative tissue damage in an animal model of acute lung injury. DESIGN: Prospective, randomized animal study. SETTING: Research laboratory of a health sciences university. SUBJECTS: Fifty New Zealand White rabbits. INTERVENTIONS: Juvenile rabbits injured by lipopolysaccharide infusion and saline lung lavage were assigned to conventional ventilation (CMV), PLV, HFOV, or high-frequency partial liquid ventilation (HF-PLV) with a full or half dose (HF-PLV1/2) of perfluorochemical (PFC). Uninjured ventilated animals served as controls. Arterial blood gases were obtained every 30 mins during the 4-hr study. Histopathologic evaluation was performed using a lung injury scoring system. Oxidative lung injury was assessed by measuring malondialdehyde and 4-hydroxynonenal in lung homogenates. MEASUREMENTS AND MAIN RESULTS: HFOV, PLV, or a combination of both methods (HF-PLV) resulted in significantly improved oxygenation, more favorable lung histopathology, reduced neutrophil infiltration, and attenuated oxidative damage compared with CMV. HF-PLV with a full PFC dose did not provide any additional benefit compared with HFOV alone. HF-PLV1/2 was associated with decreased pulmonary leukostasis compared with HF-PLV. CONCLUSIONS: The combination of HFOV and PLV (HF-PLV) does not provide any additional benefit compared with HFOV or PLV alone in a combined model of lung injury when lung recruitment and volume optimization can be achieved. The use of a lower PFC dose (HF-PLV1/2) is associated with decreased pulmonary leukostasis compared with HF-PLV and deserves further study. 相似文献
62.
Léa Rodrigues-Simioni Stella R Zamunér José C Cogo Caroline R Borja-Oliveira Júlia Prado-Franceschi Maria Alice da Cruz-H?fling Alexandre P Corrado 《Toxicon》2004,43(6):633-638
Whereas the presynaptic action of Crotalus durissus terrificus venom is well-established, Bothrops venoms have historically been considered to have only postsynaptic and muscular effects. However, some studies have also suggested a presynaptic action for these venoms. In this work, we used chick biventer cervicis preparations to compare the presynaptic actions of two Bothrops venoms (B. insularis and B. neuwiedi) with that of C. d. terrificus venom. At 10 microg/ml, all venoms produced irreversible blockade of the twitch tension responses, with no reduction in acetylcholine (ACh)-induced contractures and only a slight decrease in potassium induced-contractures. The times (in min) required to produce 50% neuromuscular blockade (C. d. terrificus: 16.3+/-0.7, n = 8; B. insularis: 30.0+/-1.9, n = 5; B. neuwiedi: 42.0+/-2.0, n = 8; mean +/- SEM) were significantly different among the venoms (p < 0.01). Lowering the temperature at which the experiments were done (from 37 to 24 degrees C) prevented neuromuscular blockade by the three venoms, indicating that enzyme activity may be involved in this response. At concentrations capable of causing complete neuromuscular blockade, creatine kinase release remained close to levels seen in control preparations incubated with Krebs solution alone (500-1200 IU/l). Commercial crotalic antivenom, but not bothropic antivenom, protected against the neuromuscular blockade caused by B. insularis and B. neuwiedi venoms. These observations indicate that bothropic venoms may contain components which act presynaptically in a manner similar to C. d. terrificus venom, and that at low venom concentrations a direct action on skeletal muscle does not contribute to this presynaptic neurotoxicity. 相似文献
63.
Alexandre de Matos Soeiro Bruno Biselli Tatiana C.A.T. Leal Aline Siqueira Bossa Maria Cristina Csar Srgio Jallad Priscila Gherardi Goldstein Patrícia Oliveira Guimares Carlos Vicente Serrano Jr Cesar Higa Nomura Dbora Nakamura Carlos Eduardo Rochitte Paulo Rogrio Soares Múcio Tavares de Oliveira Jr. 《Arquivos brasileiros de cardiologia》2022,118(5):894
BackgroundCoronary tomography angiography (CTA) has been mainly used for chest pain evaluation in low-risk patients, and few data exist regarding patients at intermediate risk.ObjectiveTo evaluate the performance of serial measures of sensitive troponin and CTA in intermediate-risk patients.MethodsA total of 100 patients with chest pain, TIMI risk scores of 3 or 4, and negative troponin were prospectively included. All patients underwent CTA and those with coronary stenosis ≥ 50% were referred to invasive coronary angiography. Patients with coronary lesions <50% were discharged and contacted 30 days later by a telephone call to assess clinical outcomes. Outcomes were hospitalization, death, and myocardial infarction at 30 days. The comparison between methods was performed by Kappa agreement test. The performance of troponin measures and CTA for detecting significant coronary lesions and clinical outcomes was calculated. Results were considered statistically significant when p < 0.05.ResultsCoronary stenosis ≥ 50% on CTA was found in 38% of patients and significant coronary lesions on coronary angiography were found in 31 patients. Two clinical events were observed. Kappa agreement analysis showed low agreement between troponin measures and CTA in the detection of significant coronary lesions (kappa = 0.022, p = 0.78). The performance of CTA for detecting significant coronary lesions on coronary angiography or for predicting clinical events at 30 days was better than sensitive troponin measures (accuracy of 91% versus 60%).ConclusionCTA performed better than sensitive troponin measures in the detection of significant coronary disease in patients with chest pain and intermediate risk for cardiovascular events. 相似文献
64.
Jorge MP Madjarof C Gois Ruiz AL Fernandes AT Ferreira Rodrigues RA de Oliveira Sousa IM Foglio MA de Carvalho JE 《Journal of ethnopharmacology》2008,118(3):361-366
ETHNOPHARMACOLOGICAL RELEVANCE: Arrabidaea chica Verlot. (Bignoniaceae), popularly known as Crajiru, has been traditionally used as wound healing agent. AIM OF THE STUDY: Investigate in vitro and in vivo healing properties of Arrabidaea chica leaves extract (AC). MATERIALS AND METHODS: AC was evaluated in vitro in fibroblast growth stimulation (0.25-250 microg/mL) and collagen production stimulation (250 microg/mL) assays. Allantoin (0.25-250 microg/mL) and vitamin C (25 microg/mL) were used as controls respectively. DPPH and Folin-Ciocalteau assays were used for antioxidant evaluation, using trolox (0.25-250 microg/mL) as reference antioxidant. To study wound healing properties in rats, AC (100mg/mL, 200 microL/wound/day) was topically administered during 10 days and wound area was evaluated every day. Allantoin (100mg/mL, 200 microL/wound/day) was used as standard drug. After treatment, wound sites were removed for histopathological analysis and total collagen determination. RESULTS: AC stimulated fibroblast growth in a concentration dependent way (EC50=30 microg/mL), increased in vitro collagen production and demonstrated moderate antioxidant capacity. In vivo, AC reduced wound size in 96%, whereas saline group showed only 36% wound healing. CONCLUSION: AC efficiency seems to involve fibroblast growing stimulus and collagen synthesis both in vitro and in vivo, beyond moderate scavenging activity, corroborating Crajiru folk use. 相似文献
65.
66.
Mir O Albiges L Arkwright S Duboc D Massault PP Tenenbaum F Touzé E Menasché P Vacher-Lavenu MC Goldwasser F Alexandre J 《Gynecologic oncology》2007,106(3):622-625
BACKGROUND: Non-bacterial thrombotic endocarditis is a severe complication of cancer, rarely reported in gynecologic tumors. However, it can be inaugural and lead to complex diagnostic pathways. CASE: A 40-year-old woman presented with a stroke, related to an endocarditis. The valvular vegetation was surgically removed, and a malignant node was resected. A PET-scan led to the diagnosis of a myometrial tumor, which was found to be a primitive neuroectodermal tumor (PNET). The patient underwent total abdominal hysterectomy with bilateral salpingo-oophorectomy, and systemic chemotherapy which allowed a complete remission of tumoral and cardio-vascular symptoms. CONCLUSION: To our knowledge, this is the first case report of a PNET of the myometrium revealed by cardio-vascular symptoms. 相似文献
67.
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69.
Rennan Garcias Moreira Julia Maria SaraivaDuarte Alexandre Costa Pereira Martha SosaMacias Carlos GalavizHernandez Meddly Lesley Santolalla Wagner C. S. Magalhes Camila Zolini Thiago Peixoto Leal Zsolt Balzs Adrin Llerena Robert H. Gilman Jos Geraldo Mill Victor Borda Heinner Guio Timothy D. OConnor Eduardo TarazonaSantos Fernanda RodriguesSoares 《CTS Clinical and Translational Science》2022,15(6):1400
70.
David Andrew McNamee Alexandre G. Legros Daniel R. Krewski Gerald Wisenberg Frank S. Prato Alex W. Thomas 《International archives of occupational and environmental health》2009,82(8):919-933
The effects of exposure to extremely low frequency (ELF) electromagnetic fields (EMFs) on human cardiovascular parameters
remain undetermined. Epidemiological studies have utilized dosimetry estimations of employee workplace exposure using altered
heart rate variability (HRV) as predictive of certain cardiovascular pathologies. Laboratory studies have focused on macrocirculatory
indicators including heart rate, HRV and blood pressure. Few studies have been conducted on the response of the microcirculatory
system to EMF exposure. Attempts to replicate both epidemiological and laboratory studies have been mostly unsuccessful as
study design, small sample populations and confounding variables have hampered progress to date. Identification of these problems,
in the current context of international exposure guideline re-evaluation, is essential for future EMF studies. These studies
should address the possible deleterious health effects of EMFs as well as the detection and characterization of subtle physiological
changes they may induce. Recommendations for future work include investigating the macro- and microcirculatory relationship
and the use of laboratory geomagnetic shielding. 相似文献