Preparation of differently sized injectable collagen micro-scaffolds

Collagen scaffolds have been widely used as biomaterials for tissue engineering. In general, application of scaffolds requires surgery. In this study, we describe a new and simple technique to prepare porous micro-scaffolds from type I collagen fibrils which can be injected, thus preventing surgery. The size of the micro-scaffolds could be easily controlled using sieves with varying cut-offs. EDC-NHS crosslinking was essential to stabilize the collagen micro-scaffolds. Micro-scaffolds were highly porous and could be injected through small diameter needles (18-21 gauge). Collagen micro-scaffolds may be used as injectables for the local delivery of effector molecules and/or cells, thus creating specific niches to enhance local tissue regeneration.     

Application of a Machine Learning Algorithm for Structural Brain Images in Chronic Schizophrenia to Earlier Clinical Stages of Psychosis and Autism Spectrum Disorder: A Multiprotocol Imaging Dataset Study

Background and HypothesisMachine learning approaches using structural magnetic resonance imaging (MRI) can be informative for disease classification; however, their applicability to earlier clinical stages of psychosis and other disease spectra is unknown. We evaluated whether a model differentiating patients with chronic schizophrenia (ChSZ) from healthy controls (HCs) could be applied to earlier clinical stages such as first-episode psychosis (FEP), ultra-high risk for psychosis (UHR), and autism spectrum disorders (ASDs).Study DesignTotal 359 T1-weighted MRI scans, including 154 individuals with schizophrenia spectrum (UHR, n = 37; FEP, n = 24; and ChSZ, n = 93), 64 with ASD, and 141 HCs, were obtained using three acquisition protocols. Of these, data regarding ChSZ (n = 75) and HC (n = 101) from two protocols were used to build a classifier (training dataset). The remainder was used to evaluate the classifier (test, independent confirmatory, and independent group datasets). Scanner and protocol effects were diminished using ComBat.Study ResultsThe accuracy of the classifier for the test and independent confirmatory datasets were 75% and 76%, respectively. The bilateral pallidum and inferior frontal gyrus pars triangularis strongly contributed to classifying ChSZ. Schizophrenia spectrum individuals were more likely to be classified as ChSZ compared to ASD (classification rate to ChSZ: UHR, 41%; FEP, 54%; ChSZ, 70%; ASD, 19%; HC, 21%).ConclusionWe built a classifier from multiple protocol structural brain images applicable to independent samples from different clinical stages and spectra. The predictive information of the classifier could be useful for applying neuroimaging techniques to clinical differential diagnosis and predicting disease onset earlier.     

Shortfalls in published neurosurgical literature

Expenditure related to neurosurgery has increased unevenly since the early 1990s. In this study we explored the literature by which clinical evidence is obtained to better direct neurosurgical practice. We searched different types of neurosurgery literature and four major neurosurgical procedures (excision of brain lesion, cerebral aneurysm clipping/coiling, discectomy, spine fusion) written in English on PubMed from 1996, the year of its launch, using the keyword "cost". Only a small and static portion of the neurosurgical literature was indexed as level I clinical evidence (randomized controlled trials), with a lack of cost appraisal in the outcome analysis of neurosurgical interventions. By way of rectification, a major increase in funding of grade I studies with cost analysis, and the requirement by peer-reviewed journals of a cost-benefit analysis, would promote the quality of clinical research yielding unquestionable advantage on national healthcare practice.     

Characteristics of laparoscopic inguinal hernia recurrences

Purpose  This is so far the largest series of recurrences after laparoscopic inguinal hernia repair. Methods   Video documents of 1,071 laparoscopic inguinal hernia repairs were retrospectively studied with respect to the affected side, anatomical appearance, gender, history and time interval between operation and recurrence. Only indirect, clinically manifest hernias were included. Results  Recurrences occurred in 32 children (3%), 26 boys and 6 girls, aged 62 days to 14 years (median 3). The right side was affected in 21 children, the left in 10 and a bilateral recurrence was noted in 1 child. A total of 25 recurrences occurred medially to the previous suture and 7 laterally. The knot became loose in three cases. An experienced surgeon had only half the recurrences of a less experienced surgeon. The median time interval between surgery and recurrence was 3.8 months. Children up to the age of 2 years had the highest risk of recurrence. The right/left incidence of recurrences roughly was in proportion to the statistical incidence of hernias. Conclusions  Boys had more recurrences than girls. Most recurrences occur medially. The more experienced the surgeon was, the fewer recurrences he had. The stitches at the medial aspect of the hernia, close to the vas, seem to be the most crucial ones.