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91.

Background

Onchocerciasis has been implicated in the pathogenesis of epilepsy. The debate on a potential causal relationship between Onchocerca volvulus and epilepsy has taken a new direction in the light of the most recent epidemic of nodding syndrome.

Objective

To document MRI changes in people with different types of epilepsy and investigate whether there is an association with O. volvulus infection.

Methods

In a prospective study in southern Tanzania, an area endemic for O. volvulus with a high prevalence of epilepsy and nodding syndrome, we performed MRI on 32 people with epilepsy, 12 of which suffered from nodding syndrome. Polymerase chain reaction (PCR) of O. volvulus was performed in skin and CSF.

Results

The most frequent abnormalities seen on MRI was atrophy (twelve patients (37.5%)) followed by intraparenchymal pathologies such as changes in the hippocampus (nine patients (28.1%)), gliotic lesions (six patients (18.8%)) and subcortical signal abnormalities (three patients (9.4%)). There was an overall trend towards an association of intraparenchymal cerebral pathologies and infection with O. volvulus based on skin PCR (Fisher''s Exact Test p=0.067) which was most pronounced in children and adolescents with nodding syndrome compared to those with other types of epilepsy (Fisher''s Exact Test, p=0.083). Contrary to skin PCR results, PCR of CSF was negative in all patients.

Conclusion

The observed trend towards an association of intraparenchymal cerebral pathological results on MRI and a positive skin PCR for O. volvulus despite negative PCR of CSF is intriguing and deserves further attention.  相似文献   
92.
To determine the phenotype and natural history of a founder genetic subtype of autosomal dominant arrhythmogenic right ventricular cardiomyopathy (ARVC) caused by a p.S358L mutation in TMEM43. The age of onset of cardiac symptoms, clinical events and test abnormalities were studied in 412 subjects (258 affected and 154 unaffected), all of which occurred in affected males significantly earlier and more often than unaffected males. Affected males were hospitalized four times more often than affected females (p ≤ 0.0001) and died younger (p ≤ 0.001). The temporal sequence from symptoms onset to death was prolonged in affected females by 1–2 decades. The most prevalent electrocardiogram (ECG) manifestation was poor R wave progression (PRWP), with affected males twice as likely to develop PRWP as affected females (p ≤ 0.05). Left ventricular enlargement (LVE) occurred in 43% of affected subjects, with 11% fulfilling criteria for dilated cardiomyopathy. Ventricular ectopy on Holter monitor was common and occurred early: the most diagnostically useful clinical test. No symptom or test could rule out diagnosis. This ARVC subtype is a sex‐influenced lethal arrhythmogenic cardiomyopathy, with a unique ECG finding, LV dilatation, heart failure and early death, where molecular pre‐symptomatic diagnosis has the greatest clinical utility.  相似文献   
93.
The effects of certain nutrients on natamycin production by Streptomyces natalensis in submerged batch culture were studied. The production of this antibiotic required glucose in the cultivation medium with a concentration of 20 g/l. On the other hand, the highest antibiotic production was obtained in a cultivation medium containing 0.05 g/l of potassium dihydrogen phosphate. Further increase in phosphate concentration resulted in a significant increase in biomass concomitant with lower antibiotic production. Among different N-sources tested, only ammonium sulphate, sodium nitrate and beef extract were the suitable nitrogen sources in supporting the antibiotic production. Furthermore, a mixture of beef extract and yeast extract (8 g/l and 2 g/l, respectively) exhibited a synergistic effect in enhancing the natamycin production reaching about 1.5 g/l.  相似文献   
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Swartz  JD; Berger  AS; Zwillenberg  S; Popky  GL 《Radiology》1987,163(3):763-765
Erosions of the ossicular chain that occurred as a complication of noncholesteatomatous chronic otitis media were studied with computed tomography (CT) in 55 patients. The incus (particularly the long and lenticular processes) was the ossicle most commonly involved (50 cases). Coronal and axial CT sections were complementary in the diagnosis of these erosions. Fibrous replacement of the incudostapedial articulation was diagnosed in four cases on axial CT scans when an unusually wide joint was present.  相似文献   
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Nowadays, an increasing number of neonatal and pediatric patients with severe heart failure benefits from extracorporeal membrane oxygenation (ECMO) support. A total of 39 pediatric patients needed venoarterial ECMO (vaECMO) support in our department between January 2008 and December 2016. Patients were retrospectively divided in two groups: 30‐day survivor group (17 patients) and 30‐day nonsurvivor group (22 patients). Outcome and factors predictive for 30‐day mortality and mid‐ as well as long‐term survival up to 7‐year follow‐up were analyzed by univariate analysis and Kaplan‐Meier survival estimation. Basic demographics and preoperative characteristics did not differ between groups (P > 0.05). 67% of patients were successfully weaned off ECMO and 44% survived 30‐day after ECMO application. After 7‐year follow‐up 28% of pediatric patients were alive. Thirty‐day survivors were significantly more likely to undergo elective cardiac surgery (P = 0.001), whereas significantly more 30‐day nonsurvivors underwent urgent surgery (P = 0.004). Odds of incidence of catecholamine refractory circulatory failure, failed myocardial recovery, and cerebral edema was significantly higher in 30‐day nonsurvivor group (41.6‐fold, 16‐fold, and 2.5‐fold, respectively). Kaplan‐Meier survival estimation analysis revealed significant differences in terms of mid‐ and long‐term survival among neonates, infants, toddlers, and preadolescents (Breslow P = 0.037 and Log‐Rank P = 0.028, respectively). vaECMO provides an efficient therapy option for life‐threatening heart disorders in neonates and pediatric patients being at high risk for myocardial failure leading to circulatory arrest. Urgency of surgery effected on higher mortality, but there was no difference in terms of mortality in 30‐day survivor group in comparison to 30‐day nonsurvivor group among neonates, infants, toddlers, and preadolescents.  相似文献   
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Diabetic foot ulcer (DFU) is a frequent complication in diabetic patients, occurring in up to 25% of those affected. Among the treatments available to clinicians, the use of bioengineered skin substitutes is an attractive alternative. Artificial dermis functions as a matrix, covering the wound and supporting healing and reconstruction of the lost tissue. This study was aimed at reviewing the use of five regeneration matrices (namely, Integra, Nevelia, Matriderm, Pelnac, and Renoskin) as reported by clinical trials. We searched Medline, Embase, ISI Web of Science, Scopus, and Cochrane Central Register of Controlled Trials databases for relevant studies. Risk of failure rates was analysed by relative risk ratio method and complete ulcer healing was studied using network meta‐analysis. Thirteen studies (12 randomized clinical trials and one cohort study) were eligible for analysis. The network meta‐analysis based on a single study for Matriderm and 12 studies for other products showed that Matriderm was statistically inferior in achieving complete ulcer healing, as compared to all other products combined. In the second phase analysis, which was limited to three studies using artificial dermis products, there was a 57% reduction in the risk of reepithelialization failure for DFU patients who used Matriderm or Pelnac, compared to those who used Pelnac with basic fibroblast growth factor spray or skin grafting. The data showed an overall low failure rate suggesting that these bioengineered skin products provide a suitable support and microenvironment for healing of DFUs with low ulcer recurrence rates. This systematic review with meta‐analysis highlights the pressing need for more studies investigating the safety, efficacy and failure rates of regeneration matrices in the treatment of DFUs.  相似文献   
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