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81.
Stolz D  Chhajed PN  Leuppi J  Pflimlin E  Tamm M 《Chest》2005,128(3):1756-1760
OBJECTIVE: Topical anesthesia for flexible bronchoscopy can be administered via transcricoid injection, nebulizer, or directly through the bronchoscope in a "spray as you go" fashion. We performed a prospective, randomized, double-blind, placebo-controlled trial to evaluate whether nebulized lidocaine provides additional benefit and reduces the total anesthetic dose required during bronchoscopy. SETTING: Tertiary care university hospital. METHODS: One hundred fifty patients (93 men; age, 20 to 89 years) undergoing diagnostic flexible bronchoscopy were randomized to receive either 4 mL of 4% lidocaine (160 mg) or 4 mL of saline solution as placebo via nebulization. Combined sedation was achieved using 5 mg of IV hydrocodone and midazolam boluses. Supplemental lidocaine doses and total midazolam required as judged by the bronchoscopist were recorded for each patient. After the procedure, both bronchoscopists and patients charted their perception of cough on a 10-cm visual analog scale (VAS). Similarly, patients recorded their discomfort related to the procedure on a 10-cm VAS. RESULTS: The most common procedures were BAL in 77 cases (51%), transbronchial biopsy in 40 cases (27%), and transbronchial needle aspiration in 34 cases (23%). Outcome parameters, including hemodynamic findings, duration of the procedure, cough scores for physicians and patients, discomfort score for patients, midazolam doses, and supplemental lidocaine doses, were similar in both groups. Mean total lidocaine dose required in the lidocaine group was 318 +/- 41 mg and was significantly higher than the total dose required in the placebo group (157 +/- 44 mg [+/- SD]) [p < 0.001]. CONCLUSION: Additional nebulized lidocaine cannot be recommended for flexible bronchoscopy performed under combined sedation.  相似文献   
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Poly(β-amino ester) networks have shown promise as tissue scaffolds. The objective of this work was to examine the effect of changing poly(ethylene glycol) diacrylate concentration on poly(β-amino ester) network properties and to assess the degradable polymers' in vivo response, using magnetic resonance imaging (MRI) and immunohistochemistry. The networks were synthesized from hexanediol diacrylate (HDDA), poly(ethylene glycol) diacrylate (PEGDA), and a primary amine, 3-methoxypropylamine (3-MOPA), with a fixed overall molar ratio of diacrylate to amine. Network properties were verified to insure that the networks possessed equivalent initial properties and structure other than chemistry. The effect of varying PEGDA concentration on water content, mass loss, and modulus was determined, where increasing the concentration of PEGDA increases both water content, mass loss rate, and decreases modulus. We also show that manipulating the network composition at ratios of 0:100, 10:90 and 25:75 (PEGDA:HDDA) does not elicit a major inflammatory response to subcutaneous implantation of the networks in mice. This work provides a foundation for tailoring poly(β-amino ester) networks, based on degradation rate and modulus, as a means to tune the polymer properties for various biomedical applications.  相似文献   
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One of the manifestations of leishmaniases is eye injuries which main characteristics are the injury of the anterior chamber of the eye and the resistance to specific treatments. The retinal pigment epithelial (RPE) cells participate in pathogen-induced intraocular inflammatory processes. We investigated Leishmania amazonensis–RPE cells relationship and its impact in laminin and fibronectin production. Using RPE cell (ARPE-19), we demonstrated that L. amazonensis adhere to these cells in the first hour of infection, whereas parasite internalization was only observed after 6 h. Seventy-two hours after infection, vacuoles with parasites debris were observed intracellularly, and no parasite were observed intra- or extracellularly at the 96 h, suggesting that Leishmania can infect ARPE-19 cells although this cells are able to clear the infection. Fibronectin and laminin were associated with L. amazonensis–ARPE-19 interaction. Confocal analysis showed no substantial alterations in fibronectin presence in ARPE-19-infected or ARPE-19-noninfected cells, whereas laminin levels increased three times 10 h after L. amazonensis infection. After this time, laminin levels decreased in infected cells. These results suggest that L. amazonensis–ARPE-19 infection induces increased production of laminin in the beginning of infection which may facilitate parasite–host cell interactions.  相似文献   
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Oxidative stress is involved in the etiology of several chronic diseases, including cardiovascular disease, diabetes, cancer, and neurodegenerative disorders. From this perspective, we have evaluated the possible antioxidant capacities of five different phthalocyanines (PCs), consisting of four metallophthalocyanines (MPCs) and one simple phthalocyanine (PC) in order to explore, for the first time, the potential antioxidant activities of these compounds. Our results show that all PCs tested in this study have significant antioxidant activity in lipid peroxidation assay, providing protection from sodium nitroprusside -induced oxidative damage to supernatant from the homogenized liver, brain, e rim of mice. Compared to the non-induced control, the PCs were generally more efficient in reducing malondialdehyde levels in all assays on lipid peroxidation induced by sodium nitroprusside; the order of approximate decrease in efficiency was as follows: manganese-PC (better efficiency)>copper-PC>iron-PC>zinc-PC>PC (worst efficiency). Furthermore, the copper-PC and manganese-PC compounds exerted a significant protective effect in deoxyribose degradation assays, when employing Fe(2+), Fe(2+)+H(2)O(2), and H(2)O(2) solutions. In conclusion, all PCs tested here were shown to be promising compounds for future in vivo investigations, because of their potential antioxidant activities in vitro.  相似文献   
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Several synthetic substances are used in agricultural areas to combat insect pests; however, the indiscriminate use of these products may affect nontarget insects, such as bees. In Brazil, one of the most widely used insecticides is imidacloprid, which targets the nervous system of insects. Therefore, the aim of this study was to evaluate the effects of chronic exposure to sublethal doses of imidacloprid on the brain of the Africanized Apis mellifera. The organs of both control bees and bees exposed to insecticide were subjected to morphological, histochemical and immunocytochemical analysis after exposure to imidacloprid, respectively, for 1, 3, 5, 7, and 10 days. In mushroom bodies of bees exposed to imidacloprid concentrations of LD50/10 and in optic lobes of bees exposed to imidacloprid concentrations of LD50/10, LD50/100, and LD50/50, we observed the presence of condensed cells. The Feulgen reaction revealed the presence of some cells with pyknotic nuclei, whereas Xylidine Ponceau stain revealed strongly stained cells. These characteristics can indicate the occurrence of cell death. Furthermore, cells in mushroom bodies of bees exposed to imidacloprid concentrations of LD50/10 appeared to be swollen. Cell death was confirmed by immunocytochemical technique. Therefore, it was concluded that sublethal doses of imidacloprid have cytotoxic effects on exposed bee brains and that optic lobes are more sensitive to the insecticide than other regions of the brain.  相似文献   
89.
Our aim was to investigate the immediate effects of bilateral, 830 nm, low-level laser therapy (LLLT) on high-intensity exercise and biochemical markers of skeletal muscle recovery, in a randomised, double-blind, placebo-controlled, crossover trial set in a sports physiotherapy clinic. Twenty male athletes (nine professional volleyball players and eleven adolescent soccer players) participated. Active LLLT (830 nm wavelength, 100 mW, spot size 0.0028 cm2, 3–4 J per point) or an identical placebo LLLT was delivered to five points in the rectus femoris muscle (bilaterally). The main outcome measures were the work performed in the Wingate test: 30 s of maximum cycling with a load of 7.5% of body weight, and the measurement of blood lactate (BL) and creatine kinase (CK) levels before and after exercise. There was no significant difference in the work performed during the Wingate test (P?>?0.05) between subjects given active LLLT and those given placebo LLLT. For volleyball athletes, the change in CK levels from before to after the exercise test was significantly lower (P?=?0.0133) for those given active LLLT (2.52 U l?1 ± 7.04 U l?1) than for those given placebo LLLT (28.49 U l?1 ± 22.62 U l?1). For the soccer athletes, the change in blood lactate levels from before exercise to 15 min after exercise was significantly lower (P?<?0.01) in the group subjected to active LLLT (8.55 mmol l?1 ± 2.14 mmol l?1) than in the group subjected to placebo LLLT (10.52 mmol l?1 ± 1.82 mmol l?1). LLLT irradiation before the Wingate test seemed to inhibit an expected post-exercise increase in CK level and to accelerate post-exercise lactate removal without affecting test performance. These findings suggest that LLLT may be of benefit in accelerating post-exercise recovery.  相似文献   
90.
BACKGROUND: A novel approach to estimate the severity of COPD exacerbation and predict its outcome is the use of biomarkers. We assessed circulating levels of copeptin, the precursor of vasopressin, C-reactive protein (CRP), and procalcitonin as potential prognostic parameters for in-hospital and long-term outcomes in patients with acute exacerbation of COPD (AECOPD) requiring hospitalization. METHODS: Data of 167 patients (mean age, 70 years; mean FEV(1), 39.9 +/- 16.9 of predicted [+/- SD]) presenting to the emergency department due to AECOPD were analyzed. Patients were evaluated based on clinical, laboratory, and lung function parameters on hospital admission, at 14 days, and at 6 months. RESULTS: Plasma levels of all three biomarkers were elevated during the acute exacerbation (p < 0.001), but levels at 14 days and 6 months were similar (p = not significant). CRP was significantly higher in patients presenting with Anthonisen type I exacerbation (p = 0.003). In contrast to CRP and procalcitonin, copeptin on hospital admission was associated with a prolonged hospital stay (p = 0.002) and long-term clinical failure (p < 0.0001). Only copeptin was predictive for long-term clinical failure independent of age, comorbidity, hypoxemia, and lung functional impairment in multivariate analysis (p = 0.005). The combination of copeptin and previous hospitalization for COPD increased the risk of poor outcome (p < 0.0001). Long-term clinical failure was observed in 11% of cases with copeptin < 40 pmol/L and no history of hospitalization, as compared to 73% of patients with copeptin >/= 40 pmol/L and a history of hospitalization (p < 0.0001). CONCLUSIONS: We suggest copeptin as a prognostic marker for short-term and long-term prognoses in patients with AECOPD requiring hospitalization.  相似文献   
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