Nanofiber Wound Dressing Materials-A Comparative Study of Wound Healing on a Porcine Model.

BACKGROUND: Nanofiber wound dressings remain the domain of in vitro studies. The purpose of our study was to verify the benefits of chitosan (CTS) and polylactide (PLA)-based nanofiber wound dressings on a porcine model of a naturally contaminated standardized wound and compare them with the conventional dressings, i.e., gauze and Inadine. MATERIAL AND METHODS: The study group included 32 pigs randomized into four homogeneous groups according to the wound dressing type. Standardized wounds were created on their backs, and wound dressings were regularly changed. We evaluated difficulty of handling individual dressing materials and macroscopic appearance of the wounds. Wound swabs were taken for bacteriological examination. Blood samples were obtained to determine blood count values and serum levels of acute phase proteins (serum amyloid A, C-reactive protein, and haptoglobin). The crucial point of the study was histological analysis. Microscopic evaluation was focused on the defect depth and tissue reactions, including formation of the fibrin exudate with neutrophil granulocytes, the layer of granulation and cellular connective tissue, and the reepithelialization. Statistical analysis was performed by using SPSS software. The analysis was based on the Kruskal-Wallis H test and Mann-Whitney U test followed by Bonferroni correction. Significance was set at P < .05. RESULTS: Macroscopic examination did not show any difference in wound healing among the groups. However, evaluation of histological findings demonstrated that PLA-based nanofiber dressing accelerated the proliferative (P = .025) and reepithelialization (P < .001) healing phases, while chitosan-based nanofiber dressing potentiated and accelerated the inflammatory phase (P = .006). No statistically significant changes were observed in the blood count or acute inflammatory phase proteins during the trial. Different dynamics were noted in serum amyloid A values in the group treated with PLA-based nanofiber dressing (P = .006). CONCLUSION: Based on the microscopic examination, we have documented a positive effect of nanofiber wound dressings on acceleration of individual phases of the healing process. Nanofiber wound dressings have a potential to become in future part of the common wound care practice.

Hypoglycemia during treatment with the ketogenic diet in a child with refractory epilepsy-results of continuous glucose monitoring.

The ketogenic diet (KD) is an effective treatment for intractable epilepsy in children. Hypoglycemia can be one of its side-effects, which is considered to be present mainly during the introductory phase of KD. Continuous glucose monitoring in a 6-year old non-diabetic child treated with KD for more than 8 months revealed long periods of asymptomatic hypoglycemia (8.9% of the total time under 2.5 mmol/l, 10.6% of the total time in the range between 2.5-3.0, 29.1% in the range of 3.0-3.6 mmol/l). The episodes of serious hypoglycemia were associated with a fasting state. The amount of sacharides in KD was increased with substantial glycemic profile improvement.

Surface Microdialysis for Detection of Colorectal Anastomosis Ischemia-An Experimental Study.

BACKGROUND: Inadequate blood supply is one of the major risk factors for anastomotic leak after low anterior rectal resection. Early detection of ischemia might predict complicated healing and enable anastomotic salvage, which is associated with better outcomes. A microdialysis offers a real-time evaluation of adequate bowel perfusion through monitoring of tissue metabolism. In this experimental study, we assessed the role of microdialysis in detecting early ischemia after colorectal anastomosis. MATERIALS AND METHODS: Colorectal anastomosis was performed in six miniature pigs. A microdialysis catheter was placed on the bowel serosa 5 mm proximal to the anastomosis. Metabolic changes were monitored hourly before and after initiating ischemia, which was induced by ligation of the inferior mesenteric artery and skeletonization of the mesocolon. RESULTS: Significant increase in tissue levels of lactate was detected after 60 min of ischemia (13.6 [10.4-16.1] versus 6.75 [1.8-9.6] mmol/L at baseline; P < 0.005). The lactate/pyruvate ratio increased accordingly. The concentration of glycerol increased significantly after 2 hours-from a baseline value of 29.5 (3-84) to 125 (79-201) mmol/L (P < 0.005). The decrease in glucose levels was also significant after 60 minutes-0 (0-0.2) versus 4.7 (3.3-6.8) mmol/L at baseline. However, its values started to decline before ischemia. CONCLUSIONS: Surface microdialysis can detect ischemic changes early and may be a promising method in postoperative monitoring of colorectal anastomosis.

Adjunctive levetiracetam in patients aged 1 month to <4 years with partial-onset seizures: subpopulation analysis of a prospective, open-label extension study of up to 48 weeks.

BACKGROUND: In a recent double-blind, placebo-controlled study, adjunctive levetiracetam (LEV) was reported to be effective and well tolerated during 5-day treatment in patients aged 1 month to <4 years with partial-onset seizures. A study was planned to fulfill the regulatory requirement to evaluate the long-term safety of LEV as adjunctive therapy for partial-onset seizures in pediatric patients. OBJECTIVE: This study evaluated the long-term effectiveness and tolerability of adjunctive LEV in infants and young children with partial-onset seizures. METHODS: This was a prospective, open-label, outpatient, multicenter study (N01148; ClinicalTrials.gov identifier NCT00152516) conducted as an extension of a previously published study (N01009; NCT00175890). Patients were enrolled from 3 sources, as follows: (1) patients who had completed study N01009; (2) patients who had failed screening for entry into study N01009 but fulfilled the eligibility criteria for entry into this study; and (3) patients who were directly enrolled. The study consisted of a 2- to 4-week retrospective baseline period (and a 3- to 10-day prospective baseline period for directly enrolled patients), a 2- to 8-week uptitration/conversion period, and a maintenance period. Eligible patients were required to have epilepsy with partial-onset seizures, treated with a stable regimen of 1 or 2 antiepileptic drugs. Patients received adjunctive LEV, 20 to 80 mg/kg/d, for up to 48 weeks (total study duration). The primary variable for effectiveness was the percentage reduction from baseline in the weekly frequency of partial-onset seizures, as recorded in patients' diaries. Data for effectiveness were also analyzed by age strata (1 month to <1 year, 1 to <2 years, and 2 to <4 years). Neuropsychological assessment was conducted with the Bayley Scales of Infant Development, Second Edition (BSID-II). All analyses were performed on observed data, and the last-observation-carried-forward approach was not used. The intent-to-treat (ITT) population was defined as all patients who took at least one dose of LEV during the study. Treatment-emergent adverse events (TEAEs) were assessed by observation, spontaneous reporting, standard questions, review of diary cards, and neuropsychologists' clinical reports. Additional measures included physical and neurologic examinations, vital signs, ECGs, routine blood chemistry, and routine hematology assessments. RESULTS: The study included 152 patients in the ITT population. In total, 51.3% (78/152) of the patients were male, and mean (SD) age was 23.5 (12.4) months. The mean LEV maintenance dose was 56.1 (16.2) mg/kg/d, and the median (Q1-Q3) treatment duration was 287.8 (209.0-295.5) days. Ninety-seven patients (63.8%) completed the study. The BSID-II subpopulation included 51 patients. During maintenance, the overall median (Q1-Q3) percentage reduction from baseline in the weekly frequency of partial-onset seizures was 56.0% (-10.9% to 92.8%), which was sustained over time and appeared comparable across the age strata (1 month to <1 year, n = 25, 50.9%; 1 to <2 years, n = 48, 58.0%; and 2 to <4 years, n = 59, 55.0%). The overall responder rate (ie, ≥50% reduction from baseline in weekly partial-onset seizures) was 53.8% (71/132), was maintained over time, and was consistent across the age strata (1 month to <1 year, 52.0%; 1 to <2 years, 56.3%; and 2 to <4 years, 52.5%). Mean BSID-II raw scores for psychomotor development and behavioral functioning remained static, whereas mental development appeared to improve over time, although this was not tested statistically. At least one TEAE was reported in 143 patients (94.1%). The most frequently reported TEAEs were pyrexia (60/152; 39.5%), upper respiratory tract infection (42/152; 27.6%), and vomiting (28/152; 18.4%). The most common TEAEs affecting the central nervous system were convulsion (25/152; 16.4%), irritability (19/152; 12.5%), and somnolence (16/152; 10.5%). Most TEAEs (77.0%) were mild or moderate in intensity. CONCLUSION: Adjunctive LEV treatment for up to 48 weeks was associated with effective and sustained seizure control and had an acceptable tolerability profile in this small, selected population of infants and young children aged 1 month to <4 years with partial-onset seizures.

Vagus nerve stimulation: longitudinal follow-up of patients treated for 5 years.

We performed a retrospective, multicenter, open-label study to evaluate the efficacy of vagus nerve stimulation (VNS) in all patients in the Czech Republic who have received this treatment for at least 5 years (n=90). The mean last follow-up was 6.6+/-1.1 years (79+/-13 months). The median number of seizures among all patients decreased from 41.2 seizures/month in the prestimulation period to 14.9 seizures/month at 5 years follow-up visit. The mean percentage of seizure reduction was 55.9%. The responder rate in these patients is in concordance with the decrease of overall seizure frequency. At 1 year after beginning the stimulation, 44.4% of patients were responders; this percentage increased to 58.7% after 2 years. At the 5 years last follow-up 64.4% of patients were responders, 15.5% experienced > or = 90% seizure reduction, and 5.5% were seizure-free. A separate analysis of patients younger than 16 years of age showed lower efficacy rates of VNS in comparison to the whole group. Complications and chronic adverse effects occurred in 13.3% of patients. VNS is an effective and safe method to refractory epilepsy in common clinical practice.

Contiguous X-chromosome deletion syndrome encompassing the BTK, TIMM8A, TAF7L, and DRP2 genes.

X-linked agammaglobulinemia (XLA) is characterized by low levels of B-lymphocytes with early-onset, recurrent, microbial infections occasionally causing neurological symptoms. We observed an atypical clinical course of XLA, complicated since early childhood with neurological impairment, progressive sensorineural deafness, and dystonia in six boys of four unrelated families. The neurologic symptoms suggested the diagnosis of Mohr-Tranebjaerg syndrome, caused by mutations in the TIMM8A gene, previously known as DDP1, and located centromerically of BTK. Deafness dystonia peptide (DDP1) participates in neurological development and is a part of the mitochondrial protein import pathway. Mutation analysis of the BTK gene revealed gross deletions of different lengths in all patients, in one case extending approximately 196 kb, including the genes TIMM8A, TAF7L, and DRP2. The most prominent clinical findings of this contiguous deletion syndrome are the combination of immunodeficiency and sensorineural deafness, which were present in all affected boys. The severity of symptoms, however, did not correlate with the extent of the deletion.

Mutation analysis of the MECP2 gene in patients of Slavic origin with Rett syndrome: novel mutations and polymorphisms.

Rett syndrome (RTT), an X-linked dominant neurodevelopmental disorder in females, is caused mainly by de novo mutations in the methyl-CpG-binding protein 2 gene (MECP2). Here we report mutation analysis of the MECP2 gene in 87 patients with RTT from the Czech and Slovak Republics, and Ukraine. The patients, all girls, with classical RTT were investigated for mutations using bi-directional DNA sequencing and conformation sensitive gel electrophoresis analysis of the coding sequence and exon/intron boundaries of the MECP2 gene. Restriction fragment length polymorphism analysis was performed to confirm the mutations that cause the creation or abolition of the restriction site. Mutation-negative cases were subsequently examined by multiple ligation-dependent probe amplification (MLPA) to identify large deletions. Mutation screening revealed 31 different mutations in 68 patients and 12 non-pathogenic polymorphisms. Six mutations have not been previously published: two point mutations (323T>A, 904C>T), three deletions (189_190delGA, 816_832del17, 1069delAGC) and one deletion/inversion (1063_1236del174;1189_1231inv43). MLPA analysis revealed large deletions in two patients. The detection rate was 78.16%. Our results confirm the high frequency of MECP2 mutations in females with RTT and provide data concerning the mutation heterogeneity in the Slavic population.

Language lateralization in children with pre- and postnatal epileptogenic lesions of the left hemisphere: an fMRI study.

Functional MRI was used to evaluate factors influencing hemispheric dominance for language in 34 children suffering from intractable focal epilepsy due to left hemispheric lesion of pre- (n = 19) or postnatal (n = 15) origin. Nineteen children (56%) exhibited pronounced left-hemispheric language dominance. Significant co-activation of the right hemisphere or a complete language shift to this hemisphere was present in 15 children (44%). Atypical language representation was detected in 6 children (31,6%) with developmental pathology and in 9 patients (60%) with acquired epileptogenic lesion. Younger age at epilepsy onset and longer duration of epilepsy correlated significantly with atypical language presentation (p < 0,017 and p < 0,025). Whereas lesser tendency of prenatal lesions to displace cortical language centers did not reach statistical significance in simple paired tests, multiple logistic regression analysis viewed positive interaction between language shift, etiology and age at epilepsy onset. In conclusion, the language network reorganization was strongly influenced by both, the age at epilepsy onset and duration of epilepsy, and to a lesser degree by the character of the epileptogenic lesion, either developmental or acquired postnatally.