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61.
Triatoma matogrossensis is a Hemiptera that belongs to the oliveirai complex, a vector of Chagas' disease that feeds on vertebrate blood in all life stages. Hematophagous insects' salivary glands (SGs) produce potent pharmacologic compounds that counteract host hemostasis, including anticlotting, antiplatelet, and vasodilatory molecules. Exposure to T. matogrossensis was also found to be a risk factor associated with the endemic form of the autoimmune skin disease pemphigus foliaceus, which is described in the same regions where Chagas' disease is observed in Brazil. To obtain a further insight into the salivary biochemical and pharmacologic diversity of this kissing bug and to identify possible allergens that might be associated with this autoimmune disease, a cDNA library from its SGs was randomly sequenced. We present the analysis of a set of 2,230 (SG) cDNA sequences, 1,182 of which coded for proteins of a putative secretory nature.  相似文献   
62.

Objective

To determine the usefulness of non-invasive ventilation (NIV) in elderly patients (≥75) admitted to a respiratory monitoring unit (RMU) during hospitalization and one year later in comparison with the results from the younger age group (<75).

Material and methods

Ours is a prospective observational study carried out at the Hospital Universitario La Princesa (Madrid, Spain). We recruited all patients who were ≥75 years old and were admitted to our RMU during the period 2008-2009 with respiratory acidosis (pH <7.35 and PaCO2 >45 mmHg) requiring NIV. We gathered data for basic variables as well as sociodemographics, history of previous pathologies, reason for hospitalization and severity, analysis upon admission and the evolution of blood gases at the start of NIV (within the first hour and after 24 hours), complications and evolution at the one-year follow-up.

Results

Mean age of the sample was 80.6 years. The Charlson index was 3.27. About half of the patients had some limitation for performing daily activities. The main reasons for admission were COPD exacerbation and heart failure. There were complications in 36% of the cases (11 renal failure and 6 atrial fibrillation). The survival rate at the one-year follow-up was 63.21%.

Conclusions

NIV is a good alternative in elderly patients admitted to the hospital with respiratory acidosis. We did not detect differences in mortality during admission between the two groups. The elderly patients were more frequently re-admitted than the younger group in the 6-12 months after hospital discharge. This could be due to their poorer functional state after hospitalization requiring NIV.  相似文献   
63.
This study was conducted in order to determine the effect of head and neck position on bilateral electromyographic (EMG) activity of the sternocleidomastoid muscles. The study was performed on 16 patients with myogenic cranio-cervical-mandibular dysfunction (CMD) and 16 healthy subjects. EMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the right and left sternocleidomastoid muscles. EMG activity was recorded in the left lateral decubitus position, in a darkened room and with the individual's eyes closed, under the following experimental conditions: 1. Head, neck, and body horizontally aligned; 2. Head and neck upwardly inclined with respect to the body, simulating the effect of a thick pillow, 3. Head and neck downwardly inclined with respect to the body, simulating the effect of a thin pillow. Variation of head and neck positions was determined by measuring the distance from the angle of neck and shoulder and the apex of the shoulder (SND = shoulder—neck distance) of each individual. Then, head and neck were forward or downwardly inclined with respect to the body at one-third of SND. A significantly higher contralateral EMG activity and a more asymmetric EMG activity were observed in the CMD group than in the healthy subjects (Kruskal-Wallis Test).These results suggest a different behavior of bilateral sternocleidomastoid EMG activity in CMD patients than in healthy subjects depending on the positioning of the head and neck.  相似文献   
64.

Introduction

Descending necrotizing mediastinitis (DNM) is a serious infection which occurs as a complication of oropharyngeal infection. Its surgical management and the routine transthoracic approach remain controversial. In this article we report our experience in the management of this disease, and review the different surgical approaches that have been reported in the medical literature.

Material and methods

A retrospective review was made of the clinical records of 29 patients treated between 1988 and 2009. Several demographic variables were analyzed, origin of the initial infection, stage of the disease according to Endo's classification, surgical technique and outcome.

Results

Surgical treatment consisted of both cervical and mediastinal drainage and radical debridement. The mediastinal drainage was made through a transcervical approach in 10 cases and transthoracic in 19, depending on the extent of the mediastinitis. The outcome was satisfactory in 24 patients and 5 died (mortality 17.2%).

Conclusions

According to our results and the conclusions of the main authors, we recommend a prompt and aggressive surgery with a transthoracic approach in cases of widespread DNM.  相似文献   
65.
Abstract

Sinus pericranii is a rare circumscribed fluctuating vascular swelling of the scalp that communicates with the intracranial venous system. It has been associated with other intracranial vascular malformations. The tumour is usually round, fluctuant, nonpulsatile, and disappears with compression. Its size increases during manoeuvers that increase the intracranial pressure. Approximately 100 cases were reported in the literature. The antecedents, different surgical procedures, differential diagnoses, and associated malformations were reviewed. [Neurol Res 1994; 16: 471–474]  相似文献   
66.
We measured immune markers in subjects with multiple sclerosis (MS) treated with IFNβ-1b for 12 months. IL-17 levels were significantly higher at Month 6 (p = 0.036) in relapsing subjects while BDNF levels were significantly higher at Month 3 (p = 0.028) in relapse-free subjects. Change from baseline in IL-4 levels inversely correlated with disability score whereas change from baseline in IL-10/IFN-gamma ratio inversely correlated with occurrence of relapses. CXCR3 + CD8 + T-cells tended to be higher but declined with treatment in relapse-free compared with relapsing subjects. Findings show the potential of cytokine and neurotrophic factors as biomarkers of clinical response to IFNβ-1b.  相似文献   
67.
This study compares the effect of tooth clenching and grinding on supra- and infrahyoid electromyographic (EMG) activity during different laterotrusive jaw posture tasks. The study included 30 healthy subjects with natural dentition and bilateral molar support, 15 with bilateral canine guidance and 15 with bilateral group function. Bipolar surface electrodes were located on the left and right supra- and infrahyoid muscles. EMG activity was recorded during the following tasks: A. eccentric grinding from intercuspal position to the right lateral edge-to-edge contact position; B. clenching in right edge-to-edge lateral contact position; C. concentric grinding from right lateral edge-to-edge contact position to intercuspal position. EMG activity was not significantly different between tasks on the working side, nonworking side, or between both sides, in subjects with canine guidance or group function (Wilcoxon rank-sum test). When comparing EMG activity by occlusal scheme, no significant differences were found either on the working side or the non-working side (Mann-Whitney U test). This result suggests that supra- and infrahyoid EMG activity in its predominant stabilizing role of the hyoid bone is not significantly modified by the type of laterotrusive occlusal scheme.  相似文献   
68.
As runners age, the likelihood of developing osteoarthritis (OA) significantly increases as 10% of people 55+ have symptomatic knee OA while 70% of people 65+ have radiographic signs of knee OA. The lateral-medial shear force (LMF) and knee adduction moment (KAM) during gait have been associated with cartilage loading which can lead to OA. Foot rotation during gait has been shown to alter the LMF and KAM, however it has not been investigated in running. The purpose of this study was to investigate changes in the KAM and LMF with foot rotation during running. Twenty participants volunteered and performed five running trials in three randomized conditions (normal foot position [NORM], external rotation [EXT], and internal rotation [INT]) at a running speed of 3.35m·s-1 on a 20 meter runway. Kinematic and kinetic data were gathered using a 9-camera motion capture system and a force plate, respectively. Repeated measures ANOVAs determined differences between conditions. The KAM and LMF were lower in both EXT and INT conditions compared to the NORM, but there were no differences between EXT and INT conditions. The decreases in KAM and LMF in the EXT condition were expected and concur with past research in other activities. The reductions in the INT condition were unexpected and contradict the literature. This may indicate that participants are making mechanical compensations at other joints to reduce the KAM and LMF in this abnormal internal foot rotation condition.

Key points

  • External rotation of the foot during running reduced the loads on the medial compartment of the knee
  • Internal rotation of the foot also reduced the medial loads, but is a more unnatural intervention
  • External and internal rotation reduced the shear forces on the knee, which may help slow the degeneration of knee joint cartilage
Key words: Osteoarthritis, cartilage, biomechanics, gait  相似文献   
69.
Neurofibroma is a benign peripheral nerve sheath tumour. It is one of the most frequent tumours of neural origin and its presence is one of the clinical criteria for the diagnosis of type 1 neurofibromatosis (NF-I). Neurofibromatosis type 1 is an autosomal dominantly inherited disease due to an alteration in the long arm of chromosome 17. About 50% of NF-I patients have no family history of the disease. NF-I patients have skin lesions (cafe au lait spots and neurofibromas) as well as bone malformations and central nervous system tumours. Diagnosis is based on a series of clinical criteria. Gingival neurofibroma in NF-I is uncommon. Treatment of neurofibromas is surgical resection. The aim of this paper is to report a case of NF-I with gingival involvement and to review the literature.  相似文献   
70.
OBJECTIVE: Neutrophils play a crucial role in the defense of invading bacteria by releasing biologically active molecules. The response of peripheral blood neutrophils was studied in periodontitis-affected patients and in healthy controls towards stimulation to Porphyromonas gingivalis (Pg) and Actinobacillus actinomycetemcomitans (Aa) extracts. MATERIALS AND METHODS: Peripheral venous blood was drawn from 23 adult patients with moderate to advanced chronic periodontitis (probing depth >or=5 mm, attachment loss >or=3 mm), and 30 healthy volunteers. Neutrophil response followed by metalloproteinase-9 (MMP-9) and interleukin-8 (IL-8) secretion was assayed by zymography and enzyme-linked immunosorbent assay, respectively, on both whole blood and purified neutrophils. In addition to periodontal pathogen extracts, known stimulating agents were tested, such as Escherichia coli-lipopolysaccharide (LPS), phytohemagglutinin, and zymosan A. RESULTS: Neutrophil response, expressed as a secretion ratio under stimulated and non-stimulated conditions, measured in whole blood, showed no differences between periodontitis and healthy controls. Instead, in purified neutrophils from patients, MMP-9 exhibited a significantly higher secretion ratio with LPS and Pg (1.5- to 2-fold), whereas IL-8 showed a larger increase in secretion ratio (3- to 7-fold) in the presence of Pg, Aa, LPS, and zymosan A. CONCLUSION: Peripheral neutrophils of periodontitis-affected patients are more reactive as suggested by their significantly higher response toward periodontal pathogen extracts and other stimulating agents.  相似文献   
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