Volumetric comparison of autogenous bone and tissue-engineered bone replacement materials in alveolar cleft repair: a systematic review and meta-analysis

The goal of reconstruction of the alveolar cleft in patients with cleft lip and palate is to improve the quality of tissue, the structural stability, and increase the volume of bone. This study is a systematic review with meta-analysis of volumetric bony filling using autogenous bone and various tissue-engineered bone substitutes. We made an electronic search on MEDLINE, EMBASE, SCOPUS, WEB OF SCIENCE, “grey” publications (materials and research produced by organisations outside traditional channels for commercial or academic publishing and distribution), and relevant cross references according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Studies that reported the outcomes of volumetric grafting were included in the meta-analysis. Of 1276 studies, 26 were included in the meta-analysis. Pooled analysis of 25 studies that used autogenous bone showed a significant reduction in the volume of the cleft equivalent to 62.0% bone fill (95% CI 54.3 to 69.6), in contrast to 10 studies that used a tissue-engineered material and reported bone filling of 68.7% (95% CI 54.5 to 82.8). The estimated sizes of pooled effects across studies showed that there was no significant difference between the two major intervention groups (p value 0.901). Our statistical analysis showed that autogenous bone grafts did not differ significantly from tissue-engineered materials in their ability to fill clefts.Systematic review registration: International Prospective Register of Systematic Reviews, PROSPERO (CRD42017065045).     

What you get is what they have? Detectability of intestinal parasites in reptiles using faeces

Parasitological analyses are often based on invasive methodologies, involving host sacrifice, raising ethical and conservation issues. However, alternative non-invasive approaches may not be always applicable due to the location of the parasite in the host tissue or the quality and reliability of the non-invasive sample per se. In this study, we compare the differences in detectability of intestinal parasites in reptiles using the classical invasive approach (intestine dissection), versus a non-invasive procedure (faecal examination), collected from the same individual host. Our results showed significantly lower detectability of helminths in faeces versus the intestine. Moreover, the number of parasites found in faeces was not explained either by the intensities found in the respective intestine or by the host identity. Several factors may explain the lack of association between the two types of samples, but more importantly, our results highlight the randomness of the presence of parasites in faeces. Even if it is not recommended that comparative studies of either parasite abundance or parasite communities be conducted on the basis of faecal samples, there are other types of studies (i.e. genetic) that can be performed with this source of information, thus avoiding the sacrifice of the host. Due to their wide spectrum of life stages and localization in the host tissue, parasites are challenging candidates for non-invasive sampling and consequently, parasitological methodologies should be carefully selected according to the objective of the study.     

Diagnosis and Management of Atypical Hemolytic Uremic Syndrome In Children: Single Centre Experience

Atypical hemolytic uremic syndrome (aHUS) although rare is the commonest cause of acute renal failure (ARF) in children and has poor prognosis. We present single centre experience of aHUS. Thirty six children (29 males, 7 females) with mean age, 7.9 years presented with ARF, 2 children also had tonic–clonic type convulsions. Their hematology examination revealed hemolytic anemia with s. creatinine (SCr), 5.54 mg/dl. Acute HUS was observed in 75 %, acute on chronic HUS in 19.4 % and patchy cortical necrosis (PCN) in 5.6 % biopsies. Mean 5.4 plasma exchanges (PE) were carried out. Supportive management of anti-hypertensives and prednisone was also given. Recovery end points were establishment of urine output, improvement of SCr and hematological profile. Hematology and renal function profile improved variably in all children, 5.6 % died, relapse was observed in 80.5 % over mean 70 days; 13.9 % children are doing well over mean follow-up of 268.8 days. Thus poor prognosis was observed in 86.1 % children. Children with acute on chronic HUS and PCN did not recover. Six children who recovered had acute HUS. aHUS in Indian children occurs at an older age of around 8 years and chronic/irreversible changes on histopathology examination are harbingers of poor prognosis. PE is life-saving however further research for developing strategies to improve long-term survival is needed.     

Multicenter Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Study for Identification of Clinically Relevant Nocardia spp.

This multicenter study analyzed Nocardia spp., including extraction, spectral acquisition, Bruker matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) identification, and score interpretation, using three Nocardia libraries, the Bruker, National Institutes of Health (NIH), and The Ohio State University (OSU) libraries, and compared the results obtained by each center. A standardized study protocol, 150 Nocardia isolates, and NIH and OSU Nocardia MALDI-TOF MS libraries were distributed to three centers. Following standardized culture, extraction, and MALDI-TOF MS analysis, isolates were identified using score cutoffs of ≥2.0 for species/species complex-level identification and ≥1.8 for genus-level identification. Isolates yielding a score of <2.0 underwent a single repeat extraction and analysis. The overall score range for all centers was 1.3 to 2.7 (average, 2.2 ± 0.3), with common species generally producing higher average scores than less common ones. Score categorization and isolate identification demonstrated 86% agreement between centers; 118 of 150 isolates were correctly identified to the species/species complex level by all centers. Nine strains (6.0%) were not identified by any center, and six (4.0%) of these were uncommon species with limited library representation. A categorical score discrepancy among centers occurred for 21 isolates (14.0%). There was an overall benefit of 21.2% from repeat extraction of low-scoring isolates and a center-dependent benefit for duplicate spotting (range, 2 to 8.7%). Finally, supplementation of the Bruker Nocardia MALDI-TOF MS library with both the OSU and NIH libraries increased the genus-level and species-level identification by 18.2% and 36.9%, respectively. Overall, this study demonstrates the ability of diverse clinical microbiology laboratories to utilize MALDI-TOF MS for the rapid identification of clinically relevant Nocardia spp. and to implement MALDI-TOF MS libraries developed by single laboratories across institutions.     

Folic acid protects against experimental prenatal nicotine–induced cardiac injury by decreasing inflammatory changes,serum TNF and COX-2 expression

Nicotine administration has been shown to increase the risk for cardiovascular diseases and death. The present study was designed to investigate the impact of nicotine administration on serum level tumor necrosis factor and cycloxygenase -2 (COX-2) expression mediated cardiac injury in rat off springs, and the possible protective effect of folic acid. Eighteen pregnant female rats were randomly divided into three groups, six animals each. Control group received the vehicle, nicotine group received a dose of nicotine 0.1?mg/kg body weight, daily with subcutaneous injection from day 3 of gestation until weaning on postnatal day 21. Nicotine treated group received daily oral supplementation with folic acid 200?mg/kg body weight by intragastric tube prior to injection of nicotine. In serum of the pups, levels of tumor necrosis factor (TNF), nitric oxide (NO), total antioxidant capacity (TAC) and malondialdehyde (MDA) were measured. Histopathological studies of cardiac tissues using hematoxylin-eosin (H&E) were carried out. The expression of COX-2 was evaluated using immunohistochemistry. Serum TNF and MDA were significantly increased, while serum NO and TAC were significantly decreased in nicotine group. Moreover, nicotine-exposed rats showed complete lysis of cardiac myocytes, marked cytoplasmic vacuolation of myocytes, muscle fibers show loss of striation and increased COX-2 expression. Concomitant folic acid administration resulted in a significant alleviation of biochemical and structural alteration-induced by nicotine. In conclusion, folic acid has a protective role against nicotine induced cardiac injury by reduction of COX-2 expression, decreasing TNF production and lipid peroxidation mediated cell injury.     

The effect of polymer molecular weight and cell seeding density on viability of cells entrapped within PEGDA hydrogel microspheres

Abstract

Cell microencapsulation can be used in tissue engineering as a scaffold or physical barrier that provides immunoisolation for donor cells. When used as a barrier, microencapsulation shields donor cells from the host immune system when implanted for cell therapies. Maximizing therapeutic product delivery per volume of microencapsulated cells necessitates first optimising the viability of entrapped cells. Although cell microencapsulation within alginate is well described, best practices for cell microencapsulation within polyethylene glycol is still being elucidated. In this study we microencapsulate mouse preosteoblast cells within polyethylene glycol diacrylate (PEGDA) hydrogel microspheres of varying molecular weight or seeding densities to assess cell viability in relation to cell density and polymer molecular weight. Diffusion studies revealed molecule size permissible by each molecular weight PEGDA towards correlating viability with polymer mesh size. Results demonstrated higher cell viability in higher molecular weight PEGDA microspheres and when cells were seeded at higher cell densities.