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101.
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BALB/c mice with pulmonary tuberculosis (TB) develop a T helper cell type 1 that temporarily controls bacterial growth. Bacterial proliferation increases, accompanied by decreasing expression of interferon (IFN)‐γ, tumour necrosis factor (TNF)‐α and inducible nitric oxide synthase (iNOS). Activation of dendritic cells (DCs) is delayed. Intratracheal administration of only one dose of recombinant adenoviruses encoding granulocyte–macrophage colony‐stimulating factor (AdGM‐CSF) 1 day before Mycobacterium tuberculosis (Mtb) infection produced a significant decrease of pulmonary bacterial loads, higher activated DCs and increased expression of TNF‐α, IFN‐γ and iNOS. When AdGM‐CSF was given in female mice B6D2F1 (C57BL/6J X DBA/2J) infected with a low Mtb dose to induce chronic infection similar to latent infection and corticosterone was used to induce reactivation, a very low bacilli burden in lungs was detected, and the same effect was observed in healthy mice co‐housed with mice infected with mild and highly virulent bacteria in a model of transmissibility. Thus, GM‐CSF is a significant cytokine in the immune protection against Mtb and gene therapy with AdGM‐CSF increased protective immunity when administered in a single dose 1 day before Mtb infection in a model of progressive disease, and when used to prevent reactivation of latent infection or transmission.  相似文献   
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In humans, IL-8 (CXCL8) is a key chemokine for chemotaxis of polymorphonuclear leukocytes and monocytes/macrophages when acting on CXCR1 and CXCR2. CXCL8 activity on neutrophils includes chemotaxis and eliciting the extrusion of neutrophil extracellular traps (NETs). In this study, we show that concentrations of IL-8 that induce NETosis surpass in at least one order of magnitude those required to elicit chemoattraction in human neutrophils. IL-8-induced NETosis was less dependent on G-proteins than migration, while extracellular Ca+2 chelation similarly inhibited both processes. Reactive oxygen species (ROS) were more important for NETosis than for chemotaxis as evidenced by neutralization with N-acetyl -cysteine. Interestingly, selective blockade with anti-CXCR1 mAb inhibited NETosis much more readily than chemotaxis, while pharmacological inhibition of both CXCR1 and CXCR2, or selective inhibition for CXCR2 alone, similarly inhibited both functions. Together, these results propose a model according to which low concentrations of IL-8 in a gradient attract neutrophils to the inflammatory foci, while high receptor-saturating concentrations of IL-8 give rise to NETosis once leukocytes reach the core of the inflammatory insult.  相似文献   
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Odontology - Endodontics has gained emphasis in the scientific community in recent years due to the increase in clinical and in animal models studies focused on endodontic medicine, which aims to...  相似文献   
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The purpose of this report is to critically evaluate our results of two intercostal nerve transfers directly to the biceps motor branch in complete traumatic brachial plexus injuries. From January 2007 to November 2012, 19 patients were submitted to this type of surgery, but only 15 of them had a follow‐up for ≥2 years and were included in this report. The mean interval from trauma to surgery was 6.88 months (ranging from 3 to 9 months). Two intercostals nerves were dissected and transferred directly to the biceps motor branch. The mean follow‐up was 38.06 months (ranging from 24 to 62 months). Ten patients (66.6%) recovered an elbow flexion strength ≥M3. Four of them (26.66%) recovered a stronger elbow flexion ≥M4. One patient (6.25%) recovered an M2 elbow flexion and four patients (26.66%) did not regain any movement. We concluded that two intercostal nerve transfers to the biceps motor branch is a procedure with moderate results regarding elbow flexion recovery, but it is still one of the few options available in complete brachial plexus injuries, especially in five roots avulsion scenario. © 2015 Wiley Periodicals, Inc. Microsurgery 35:428–431, 2015.  相似文献   
108.
OBJECTIVES: Prior reports have found a temporal association between the introduction of highly active antiretroviral therapy (HAART) and population rates of health service use among persons living with HIV. Our objective was to explore further the effect of HAART by comparing healthcare use among persons who use HAART and persons who discontinue HAART to that among HAART-naive and HIV-negative persons. METHODS: Longitudinal analyses of 1485 women with and at-risk for HIV who contributed data to the Women's Interagency HIV Study between April 1997 and March 2000. RESULTS: Compared with HAART-naive women, those using HAART had a higher probability of more than three primary care visits per 6 months [odds ratio (OR), 1.38; 95% confidence interval (CI), 1.16-1.65), a lower probability of more than one emergency room visit per 6 months (OR, 0.75; CI, 0.59-0.95), and a lower probability of more than one hospitalization per 6 months (OR, 0.67; CI, 0.51-0.88). Compared with HAART-naive women, women who had discontinued HAART had a higher frequency of primary care visits (OR, 1.57; CI, 1.26-1.97) but did not demonstrate a significant change in emergency room or hospital use. Modeling of a standardized population HIV-positive women without AIDS indicated hospitalization and emergency room use among HAART users was equivalent to that among HIV-negative women. CONCLUSIONS: HIV-positive HAART users (without AIDS) exhibited emergency room and hospitalization use patterns equivalent to those of HIV-negative women. Furthermore, the discontinuation of HAART was associated with a loss of the reduction in hospital use that was achieved with HAART.  相似文献   
109.
Percutaneous transluminal coronary angioplasty is an accepted treatment for selected patients with single vessel disease but has not been rigorously evaluated in patients with double vessel disease. Among 769 patients undergoing transluminal coronary angioplasty between 1980 and 1984, 74 with double vessel stenosis of 50% or more underwent double vessel coronary angioplasty. Primary success was obtained for both lesions in 63 patients (85%), for one lesion in 11 patients (15%) and for 137 (93%) of 148 segments overall. Except for myocardial infarction in one patient, no serious complication occurred. Before coronary angioplasty, 15 patients had unstable angina, 14 had Canadian Cardiovascular Society class III and 32 class I to II effort angina and only 2 were asymptomatic. Six months after coronary angioplasty, 27 were asymptomatic, 27 had class I to II and 5 had class III effort angina and 2 had sustained an episode of unstable angina. During the follow-up study, two patients had an infarction and one had coronary artery bypass surgery. Coronary arteriography was performed at a mean of 5.5 +/- 2.1 months after coronary angioplasty in all but three patients. Restenosis was found in 30 (23%) of 132 segments with angiographic control. Restenosis was present in one vessel in 17 patients and in both vessels in 4; 40 patients (66%) had no restenosis. Of the 34 patients with definite or probable angina, 50% had restenosis and 19% of patients with restenosis were symptom free.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
110.
The larval stage of the parasite Echinococcus granulosus causes hydatid disease. The hydatid cyst is potentially capable of activating host complement, since it is a large, persistent, carbohydrate-rich structure, coated with host immunoglobulins, and localized in the host's internal organs. Nonetheless, in vitro studies have suggested that the cyst surface, the hydatid cyst wall (HCW), is a poor complement activator. In this study, we assessed the occurrence of in vivo complement activation on the hydatid cyst by measuring the levels of two complement activation products, C3d and complexes bearing a C9 activation neoepitope (TCC/MAC), in extracts from HCW of human origin. Low amounts of C3d and TCC/MAC were found in HCW in comparison with their levels in normal human plasma and activated human sera, suggesting that in vivo complement activation on HCW is efficiently down-regulated. This regulation may contribute to limit host inflammation which has been observed to correlate with parasite degeneration and death.  相似文献   
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