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We performed a study to analyze epidemiological characteristics and bacteriological profile of infectious endocarditis (I.E) in the area of Sfax (Tunisia). We analyzed, retrospectively, all cases of I.E, according to Duke Criteria, hospitalized in the CHU Hédi Chaker of Sfax between January 1997 and December 2000. Bacteriological investigation included blood culture, cardiac valve culture and serology. Seventy-two cases of I.E were diagnosed. The average of age was 32.3 years. 47.3% of the patients did not have cardiac disease, 25% had a valvular prosthesis, 20.8% a native valvulopathy and 6.9% a congenital cardiopathy. Antecedent of acute rheumatic fever was noted in 66% of I.E on native valvulopathy and in 55.5% of I.E on prosthesis. The mitral valve was involved in 39%, the aortic in 27.5% and the two in 26% of the cases. The origin of bacteremia was found or supposed in 55.5% of the cases and was commonly dental (33 % of EI). The bacteriological diagnosis was positive in 51 cases (70.8%). Staphylococci were isolated in 17 cases (23.6%), Streptococci in 17 cases (23.6%) and dominated by oral streptococci (12 cases). Chlamydial serology was positive in 8 cases (11.1%). Diagnosis of infectious endocarditis due to Chlamydia pneumoniae was confirmed in a case by genomic amplification (PCR) and in situ hybridization on the valve. Endocarditis in Tunisia remains frequent. It reaches with predilection the young person in particular with rheumatic heart diseases. The bacteriological profile remains dominated by Streptococci and the Staphylococci.  相似文献   
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Introduction: Phrenic nerve injury (PNI) is a complication that can occur with catheter ablation.
Methods: Data from 17 patients with PNI following different catheter ablation techniques were reviewed. PNI was defined as decreased motility (transient) or paralysis (persistent) of the hemi-diaphragm on fluoroscopy or chest X-ray. Patient's recovery was monitored. Normalization of chest images and sniff test would be considered as complete clinical recovery.
Results: Out of the 17 PNI patients (16 right, 1 left), 13 (11 persistent, 2 transient) occurred after pulmonary veins isolation with or without superior vena cava ablation. Three patients had persistent PNI after sinus node modification and one other patient experienced PNI after epicardial ventricular tachycardia ablation. Ablation was performed with different energy source including radiofrequency  (n = 13)  , cryothermal  (n = 1)  , ultrasound  (n = 2)  and laser  (n = 1)  . Patient's symptoms varied broadly from asymptomatic to dyspnea, and even to respiratory insufficiency that required temporary mechanical ventilation support. Two patients with transient PNI resolved immediately after the procedure and the other 15 persistent PNI patients resolved within a mean time of  8.3 ± 6.6 months  .
Conclusions: PNI caused by catheter ablation appears to functionally recover over time regardless of the energy sources used for the procedure.  相似文献   
45.
Multielectrode arrays have enabled electrophysiological experiments exploring spatio-temporal dynamics previously unattainable with single electrode recordings. The finite number of electrodes in planar MEAs (pMEAs), however, imposes a trade-off between the spatial resolution and the recording area. This limitation was circumvented in this paper through the custom design of experiment-specific tissue-conformal high-density pMEAs (cMEAs). Four configurations were presented as examples of cMEAs designed for specific stimulation and recording experiments in acute hippocampal slices. These cMEAs conformed in designs to the slice cytoarchitecture whereas their high-density provided high spatial resolution for selective stimulation of afferent pathways and current source density (CSD) analysis. The cMEAs have 50 or 60 microm center-to-center inter-electrode distances and were manufactured on glass substrates by photolithographically defining ITO leads, insulating them with silicon nitride and SU-8 2000 epoxy-based photoresist and coating the etched electrode tips with gold or platinum. The ability of these cMEAs to stimulate and record electrophysiological activity was demonstrated by recording monosynaptic, disynaptic, and trisynaptic field potentials. The conformal designs also facilitated the selection of the optimal electrode locations for stimulation of specific afferent pathways (Schaffer collaterals; medial versus lateral perforant path) and recording the corresponding responses. In addition, the high-density of the arrays enabled CSD analysis of laminar profiles obtained through sequential stimulation along the CA1 pyramidal tree.  相似文献   
46.
A 5-year-old boy with cat scratch disease presented with fever of unknown origin and osteomyelitis of the thoracic spine and epidural abscess. He did not have localizing signs or symptoms. Computed tomography of the abdomen, which was initially negative, showed hepatosplenic disease. Cat scratch disease has variable systemic presentations and should be included in the differential diagnosis of fever of unknown origin if an epidemiologic risk factor is present.  相似文献   
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We recently showed that oligomerization of CD40 molecules on cell surface leads to disulfide-linked CD40/CD40 dimer formation, an event that is necessary for CD40-induced B7-2 expression in human B cells. Here, we demonstrate that CD40/CD40 dimers formation also occurs in different cell types such as T24 bladder cancer cells and CD40-transfected HEK 293 cells. Disulfide bonds mediate the formation of CD40/CD40 homodimers in CD40-activated cells. To determine the potential residue(s) involved in disulfide bonds formation and subsequent CD40-induced IL-8 expression, we generated a CD40 mutant in which the extracellular cysteine 6 was replaced by a glutamine (CD40-C6Q). CD40-induced IL-8 mRNA expression and protein synthesis were studied in stably transfected HEK 293 cells that were sorted out along with similar levels of expression of wild type (CD40-WT) and CD40-C6Q molecules. In contrast to cells expressing CD40-WT protein, disulfide-linked CD40/CD40 dimer formation was completely abolished in HEK 293 cells expressing CD40-C6Q proteins. Abolishment of disulfide-linked CD40/CD40 dimers in these transfected cells was sufficient to inhibit CD40-induced mRNA expression and secretion of IL-8. This study identifies the extracellular cysteine 6 of CD40 molecules as a potential molecular target to disrupt the expression of CD40-induced pro-inflammatory cytokines by epithelial cells.  相似文献   
49.
The fruits (dates) of the date palm (Phoenix dactylifera L.) contain a high percentage of carbohydrate (total sugars, 44-88%), fat (0.2-0.5%), 15 salts and minerals, protein (2.3-5.6%), vitamins and a high percentage of dietary fibre (6.4-11.5%). The flesh of dates contains 0.2-0.5% oil, whereas the seed contains 7.7-9.7% oil. The weight of the seed is 5.6-14.2% of the date. The fatty acids occur in both flesh and seed as a range of saturated and unsaturated acids, the seeds containing 14 types of fatty acids, but only eight of these fatty acids occur in very low concentration in the flesh. Unsaturated fatty acids include palmitoleic, oleic, linoleic and linolenic acids. The oleic acid content of the seeds varies from 41.1 to 58.8%, which suggests that the seeds of date could be used as a source of oleic acid. There are at least 15 minerals in dates. The percentage of each mineral in dried dates varies from 0.1 to 916 mg/100 g date depending on the type of mineral. In many varieties, potassium can be found at a concentration as high as 0.9% in the flesh while it is as high as 0.5% in some seeds. Other minerals and salts that are found in various proportions include boron, calcium, cobalt, copper, fluorine, iron, magnesium, manganese, potassium, phosphorous, sodium and zinc. Additionally, the seeds contain aluminum, cadmium, chloride, lead and sulphur in various proportions. Dates contain elemental fluorine that is useful in protecting teeth against decay. Selenium, another element believed to help prevent cancer and important in immune function, is also found in dates. The protein in dates contains 23 types of amino acids, some of which are not present in the most popular fruits such as oranges, apples and bananas. Dates contain at least six vitamins including a small amount of vitamin C, and vitamins B(1) thiamine, B(2) riboflavin, nicotinic acid (niacin) and vitamin A. The dietary fibre of 14 varieties of dates has been shown to be as high as 6.4-11.5% depending on variety and degree of ripeness. Dates contain 0.5-3.9% pectin, which may have important health benefits. The world production of dates has increased 2.9 times over 40 years, whereas the world population has doubled. The total world export of dates increased by 1.71% over 40 years. In many ways, dates may be considered as an almost ideal food, providing a wide range of essential nutrients and potential health benefits.  相似文献   
50.
BACKGROUND: Pleural effusion (PE) is a rare complication of advanced liver cirrhosis, which may lead to an operation when uncontrolled. The purpose of this study was to evaluate the modality of the occurrence of pleural effusion and to describe its surgical management. METHODS: We studied 21 patients who were referred to the department of thoracic surgery because of massive and recurrent PE caused by liver cirrhosis. The PE was a transudate in 16 patients and an exudate in 5. Talc pleurodesis was attempted in all patients. The patients were divided into two groups. Video assisted thoracoscopy was performed in 13 patients in whom the clinical condition permitted general anesthesia; the pleural cavity was entirely explored before pleurodesis (group 1). Chest tube drainage alone was performed in 8 patients who were unable to undergo general anesthesia; talc pleurodesis was performed through the chest tube in these patients (group 2). RESULTS: In group 1 the PE was right-sided in 8 patients, left-sided in 3, and bilateral in 2. Diaphragmatic defects were observed in 2 patients, and a fluid leak oozing from the diaphragm was observed in 1 patient. Ten patients were considered cured and were without recurrence. Two patients underwent late recurrence before dying from their liver cirrhosis. Only 1 patient had an early recurrence that was cured by complementary talc slurry. In group 2 all patients presented with a right PE; of these, 3 patients died from septic shock caused by pleural infection. Three patients underwent early recurrence but were cured after repeat talc slurry. One patient had a midterm recurrence. One patient had an early recurrence treated by intrahepatic porto-systemic shunt with partial improvement. CONCLUSIONS: Passage of ascites through diaphragmatic defects appears to be the main cause of PE complicating cirrhosis. Patients may benefit from talc pleurodesis. Video assisted thoracoscopy pleurodesis is the technique of choice with consistent results. Repeated talc injection through the drain may prove useful for patients in poor clinical status.  相似文献   
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