Surgical repair of the supraspinatus: pre- and postoperative architectural changes in the muscle.

INTRODUCTION: Shortening of the tendon and muscle is recognised as a strong predictor of surgical failure of supraspinatus tendon tears. Changes in muscle architecture following repair have not been thoroughly investigated. Hence, we aimed to compare the pre- and postoperative architecture of the supraspinatus. METHODS: We recruited eight participants with full-thickness supraspinatus tears. Images of the supraspinatus were captured preoperatively (pre-op) and postoperatively at one month (post-op1), three months (post-op2) and six months (post-op3) in relaxed and contracted states (0º and 60º glenohumeral abduction). Fibre bundle length (FBL), pennation angle (PA) and muscle thickness were quantified. Self-reported function, and maximal isometric abduction and external rotation strengths were assessed. RESULTS: The mean FBL increased from pre-op to post-op1 (p = 0.001) in the relaxed state and from pre-op to post-op2 (p = 0.002) in the contracted state. Decrease in FBL was observed from post-op2 to post-op3 in the relaxed state. The mean PA decreased from pre-op to post-op1 (p < 0.001) in the relaxed state, but increased from post-op2 to post-op3 in both relaxed (p = 0.006) and contracted (p = 0.004) states. At post-op3, external rotation (p = 0.009) and abduction (p = 0.005) strengths were greater than at post-op2. Overall function increased by 47.67% from pre-op to post-op3. CONCLUSION: Lengthening of the supraspinatus occurs with surgery, altering the length-tension relationship of the muscle, which can compromise muscle function and lead to inferior surgical outcomes. These findings may guide clinicians to optimise loads, velocities and shoulder ranges for effective postoperative rehabilitation.

BMP signaling mediates glioma stem cell quiescence and confers treatment resistance in glioblastoma.

Despite advances in therapy, glioblastoma remains an incurable disease with a dismal prognosis. Recent studies have implicated cancer stem cells within glioblastoma (glioma stem cells, GSCs) as mediators of therapeutic resistance and tumor progression. In this study, we investigated the role of the transforming growth factor-ß (TGF-ß) superfamily, which has been found to play an integral role in the maintenance of stem cell homeostasis within multiple stem cell systems, as a mediator of stem-like cells in glioblastoma. We find that BMP and TGF-ß signaling define divergent molecular and functional identities in glioblastoma, and mark relatively quiescent and proliferative GSCs, respectively. Treatment of GSCs with BMP inhibits cell proliferation, but does not abrogate their stem-ness, as measured by self-renewal and tumorigencity. Further, BMP pathway activation confers relative resistance to radiation and temozolomide chemotherapy. Our findings define a quiescent cancer stem cell population in glioblastoma that may be a cellular reservoir for tumor recurrence following cytotoxic therapy.

ID1 Is Critical for Tumorigenesis and Regulates Chemoresistance in Glioblastoma.

Glioblastoma is the most common primary brain tumor in adults. While the introduction of temozolomide chemotherapy has increased long-term survivorship, treatment failure and rapid tumor recurrence remains universal. The transcriptional regulatory protein, inhibitor of DNA-binding-1 (ID1), is a key regulator of cell phenotype in cancer. We show that CRISPR-mediated knockout of ID1 in glioblastoma cells, breast adenocarcinoma cells, and melanoma cells dramatically reduced tumor progression in all three cancer systems through transcriptional downregulation of EGF, which resulted in decreased EGFR phosphorylation. Moreover, ID1-positive cells were enriched by chemotherapy and drove tumor recurrence in glioblastoma. Addition of the neuroleptic drug pimozide to inhibit ID1 expression enhanced the cytotoxic effects of temozolomide therapy on glioma cells and significantly prolonged time to tumor recurrence. Conclusively, these data suggest ID1 could be a promising therapeutic target in patients with glioblastoma. SIGNIFICANCE: These findings show that the transcriptional regulator ID1 is critical for glioblastoma initiation and chemoresistance and that inhibition of ID1 enhances the effect of temozolomide, delays tumor recurrence, and prolongs survival.

Evaluation of different phenotypic tests for detection of metallo-ß-lactamases in imipenem-resistant Pseudomonas aeruginosa.

PURPOSE: Pseudomonas aeruginosa causes a wide spectrum of infections including bacteremia, pneumonia, urinary tract infection, etc., Metallo-beta-lactamase (MBL) producing P. aeruginosa is an emerging threat and cause of concern as they have emerged as one of the most feared resistance mechanisms. This study was designed to know the prevalence of MBL production in P. aeruginosa and to evaluate the four phenotypic tests for detection of MBL production in imipenem-resistant clinical isolates of P. aeruginosa. METHODS: Totally, 800 isolates of P. aeruginosa isolated from various clinical samples were evaluated for carbapenem resistance and MBL production. All imipenem-resistant strains were tested for carabapenemase production by modified Hodge test. Screening for MBL production was done by double-disc synergy test and combined disc test (CDT). Confirmation of MBL production was done by the E-test (Ab BioDisk, Solna, Sweden). RESULTS: Out of the 800 isolates of P. aeruginosa, 250 isolates were found resistant to imipenem. Based on the results of E-test, 147 (18.37%) isolates of P. aeruginosa were positive for MBL production. The CDT has the highest sensitivity and specificity for the detection of MBL production as compared to other tests. CONCLUSION: The results of this study are indicative that MBL production is an important mechanism of carbapenem resistance among P. aeruginosa. Use of simple screening test like CDT will be crucial step toward large-scale monitoring of these emerging resistant determinants. Phenotypic test for MBL production has to be standardized, and all the isolates should be routinely screened for MBL production.

Angelman syndrome: A review highlighting musculoskeletal and anatomical aberrations.

Angelman's syndrome (AS) is a genetic neurodevelopment disorder. The cause is a known abnormality involving the maternal inherited ubiquitin-protein ligase (UBE3A) gene. Clinical characteristics universal to the disorder are well documented in the literature and include developmental delay, seizures, ataxia, altered tone, severely impaired speech and intellect, as well as an overall happy demeanor, frequent bouts of laughter, and hypermotoric behavior. Associated with this disorder are several musculoskeletal aberrations. To date, a review of case studies reporting on these musculoskeletal changes has not been carried out. Thus, the purpose of this paper was to provide an overview of the musculoskeletal changes present in individuals with AS. In our review of 21 case reports from 1965-2013, the most consistently reported anatomical changes were of the craniofacial region. These include microcephaly, brachycephaly, a palpable occipital groove, prognathism, and wide spaced teeth. Other musculoskeletal abnormalities less frequently reported in the literature include scoliosis, excessive lumbar lordosis, and pes planus. Given that the majority of the case reports reviewed was of young children, the possibility of underreporting musculoskeletal changes which may manifest in the later years of life may be present. Early diagnosis and interventions to minimize secondary complications are crucial to maintain quality of life. An overall multidisciplinary approach is emphasized to maximize developmental potential for these individuals. Future prospective studies that follow patients into adulthood are needed to better understand the prevalence and development of secondary musculoskeletal changes, which in turn can inform intervention techniques and preventative measures. Clin. Anat. 29:561-567, 2016. © 2015 Wiley Periodicals, Inc.

Change in the Pathologic Supraspinatus: A Three-Dimensional Model of Fiber Bundle Architecture within Anterior and Posterior Regions.

Supraspinatus tendon tears are common and lead to changes in the muscle architecture. To date, these changes have not been investigated for the distinct regions and parts of the pathologic supraspinatus. The purpose of this study was to create a novel three-dimensional (3D) model of the muscle architecture throughout the supraspinatus and to compare the architecture between muscle regions and parts in relation to tear severity. Twelve cadaveric specimens with varying degrees of tendon tears were used. Three-dimensional coordinates of fiber bundles were collected in situ using serial dissection and digitization. Data were reconstructed and modeled in 3D using Maya. Fiber bundle length (FBL) and pennation angle (PA) were computed and analyzed. FBL was significantly shorter in specimens with large retracted tears compared to smaller tears, with the deeper fibers being significantly shorter than other parts in the anterior region. PA was significantly greater in specimens with large retracted tears, with the superficial fibers often demonstrating the largest PA. The posterior region was absent in two specimens with extensive tears. Architectural changes associated with tendon tears affect the regions and varying depths of supraspinatus differently. The results provide important insights on residual function of the pathologic muscle, and the 3D model includes detailed data that can be used in future modeling studies.

Influence of standardization on the precision (reproducibility) of dental cast analysis with virtual 3-dimensional models.

INTRODUCTION: Virtual 3-dimensional (3D) models obtained by scanning of physical casts have become an alternative to conventional dental cast analysis in orthodontic treatment. If the precision (reproducibility) of virtual 3D model analysis can be further improved, digital orthodontics could be even more widely accepted. The purpose of this study was to clarify the influence of "standardization" of the target points for dental cast analysis using virtual 3D models. Physical plaster models were also measured to obtain additional information. METHODS: Five sets of dental casts were used. The dental casts were scanned with R700 (3Shape, Copenhagen, Denmark) and REXCAN DS2 3D (Solutionix, Seoul, Korea) scanners. In this study, 3 system and software packages were used: SureSmile (OraMetrix, Richardson, Tex), Rapidform (Inus, Seoul, Korea), and I-DEAS (SDRC, Milford, Conn). RESULTS: Without standardization, the maximum differences were observed between the SureSmile software and the Rapidform software (0.39 mm ± 0.07). With standardization, the maximum differences were observed between the SureSmile software and measurements with a digital caliper (0.099 mm ± 0.01), and this difference was significantly greater (P <0.05) than the 2 other mean difference values. Furthermore, the results of this study showed that the mean differences "WITH" standardization were significantly lower than those "WITHOUT" standardization for all systems, software packages, or methods. CONCLUSIONS: The results showed that elimination of the influence of usability or habituation is important for improving the reproducibility of dental cast analysis.

TRIM28 represses transcription of endogenous retroviruses in neural progenitor cells.

TRIM28 is a corepressor that mediates transcriptional silencing by establishing local heterochromatin. Here, we show that deletion of TRIM28 in neural progenitor cells (NPCs) results in high-level expression of two groups of endogenous retroviruses (ERVs): IAP1 and MMERVK10C. We find that NPCs use TRIM28-mediated histone modifications to dynamically regulate transcription and silencing of ERVs, which is in contrast to other somatic cell types using DNA methylation. We also show that derepression of ERVs influences transcriptional dynamics in NPCs through the activation of nearby genes and the expression of long noncoding RNAs. These findings demonstrate a unique dynamic transcriptional regulation of ERVs in NPCs. Our results warrant future studies on the role of ERVs in the healthy and diseased brain.

microRNA-125 distinguishes developmentally generated and adult-born olfactory bulb interneurons.

New neurons, originating from the subventricular zone, are continuously integrating into neuronal circuitry in the olfactory bulb (OB). Using a transgenic sensor mouse, we found that adult-born OB interneurons express microRNA-125 (miR-125), whereas the pre-existing developmentally generated OB interneurons represent a unique population of cells in the adult brain, without miR-125 activity. Stable inhibition of miR-125 in newborn OB neurons resulted in enhanced dendritic morphogenesis, as well as in increased synaptic activation in response to odour sensory stimuli. These data demonstrate that miR-125 controls functional synaptic integration of adult-born OB interneurons. Our results also suggest that absence of an otherwise broadly expressed miRNA is a novel mechanism with which to achieve neuronal subtype specification.

Visualization and genetic modification of resident brain microglia using lentiviral vectors regulated by microRNA-9.

Functional studies of resident microglia require molecular tools for their genetic manipulation. Here we show that microRNA-9-regulated lentiviral vectors can be used for the targeted genetic modification of resident microglia in the rodent brain. Using transgenic reporter mice, we demonstrate that murine microglia lack microRNA-9 activity, whereas most other cells in the brain express microRNA-9. Injection of microRNA-9-regulated vectors into the adult rat brain induces transgene expression specifically in cells with morphological features typical of ramified microglia. The majority of transgene-expressing cells colabels with the microglia marker Iba1. We use this approach to visualize and isolate activated resident microglia without affecting circulating and infiltrating monocytes or macrophages in an excitotoxic lesion model in rat striatum. The microRNA-9-regulated vectors described here are a straightforward and powerful tool that facilitates functional studies of resident microglia.

MicroRNA-124 is a subventricular zone neuronal fate determinant.

New neurons are continuously generated from neural stem cells with astrocyte properties, which reside in close proximity to the ventricle in the postnatal and adult brain. In this study we found that microRNA-124 (miR-124) dictates postnatal neurogenesis in the mouse subventricular zone. Using a transgenic reporter mouse we show that miR-124 expression is initiated in the rapid amplifying progenitors and remains expressed in the resulting neurons. When we stably inhibited miR-124 in vivo, neurogenesis was blocked, leading to the appearance of ectopic cells with astrocyte characteristics in the olfactory bulb. Conversely, when we overexpressed miR-124, neural stem cells were not maintained in the subventricular zone and neurogenesis was lost. In summary, our results demonstrate that miR-124 is a neuronal fate determinant in the subventricular zone.

Treatment time: SureSmile vs conventional.

AIM: To understand the efficiency of SureSmile treatment vs conventional treatment. METHODS: First, 12,335 completed patient histories representing different treatment philosophies and geographically diverse practices were collected. Included were 9,390 SureSmile patients and 2,945 conventional patients. Variables in these patient records included: (1) treatment time, months from bonding to debonding; (2) malocclusion class, Angle Class I, II, or III; (3) patient age, adolescents (< 18 years) or adults (≥ 18 years); and (4) patient visits, total number of treatment visits. Nonparametric regression tests were used to analyze the data. RESULTS: The median treatment time for the SureSmile patient pool (15 months) was 8 months shorter than that of the conventional patient pool (23 months). The median care cycle length of Class II SureSmile patients (13 months) was 2 months shorter than that of Class I SureSmile patients (15 months) and 3 months shorter than that of Class III SureSmile patients (16 months). SureSmile patients (14 visits) had four fewer median treatment visits than conventional patients (18 visits). All results were significant at P = .001. No significant differences were noted between the median care cycle lengths of adolescents and adults. CONCLUSION: This study found that SureSmile treatment facilitates more timely care than conventional treatment. Further prospective studies are required to elucidate the effectiveness of SureSmile treatment.

Functional Studies of microRNAs in Neural Stem Cells: Problems and Perspectives.

In adult mammals, neural stem cells (NSCs) are found in two niches of the brain; the subventricular zone by the lateral ventricles and the subgranular zone of the dentate gyrus in the hippocampus. Neurogenesis is a complex process that is tightly controlled on a molecular level. Recently, microRNAs (miRNAs) have been implicated to play a central role in the regulation of NCSs. miRNAs are small, endogenously expressed RNAs that regulate gene expression at the post-transcriptional level. However, functional studies of miRNAs are complicated due to current technical limitations. In this review we describe recent findings about miRNAs in NSCs looking closely at miR-124, miR-9, and let-7. In addition, we highlight technical strategies used to investigate miRNA function, accentuating limitations, and potentials.

Tracking differentiating neural progenitors in pluripotent cultures using microRNA-regulated lentiviral vectors.

In this study, we have used a microRNA-regulated lentiviral reporter system to visualize and segregate differentiating neuronal cells in pluripotent cultures. Efficient suppression of transgene expression, specifically in undifferentiated pluripotent cells, was achieved by using a lentiviral vector expressing a fluorescent reporter gene regulated by microRNA-292. Using this strategy, it was possible to track progeny from murine ES, human ES cells, and induced pluripotent stem cells as they differentiated toward the neural lineage. In addition, this strategy was successfully used to FACS purify neuronal progenitors for molecular analysis and transplantation. FACS enrichment reduced tumor formation and increased survival of ES cell-derived neuronal progenitors after transplantation. The properties and versatility of the microRNA-regulated vectors allows broad use of these vectors in stem cell applications.

Vector fragmentation: characterizing vector integrity in transfected clones by Southern blotting.

The Chinese Hamster Ovary production cell line development process using methotrexate (MTX) amplification is well studied and commonly used for biopharmaceutical processes. However, successful MTX amplification varies from clone to clone and suggested reasons include vector fragmentation during the transfection process and genomic rearrangement of the Chinese Hamster Ovary chromosomes. Here, we elucidated the vector integration patterns of 40 transfected single-cell clones by Southern blotting and showed that vector fragmentation occurs at a significant level in our experiment. This concurs with MTX amplification studies implying that single-cell cloning is necessary to ensure a successful amplification process. Truncations at the ends of the integrated vectors were also observed, whereas gross DNA insertions were not detected in our data. This suggests that end deletions are common, whereas insertion events are rare in animal cells.

Long-term stability of Class I premolar extraction treatment.

This study evaluates Class I, 4-premolar-extraction patients who were treated with the edgewise appliance by 1 practitioner, according to the philosophy of Tweed, and who had been out of retention a minimum of 5 years. The sample includes 32 patients, who started treatment at an average age of 12.8 years and who were examined a mean of 15 years posttreatment (11.7 years postretention). Cephalometric and model analyses were conducted to evaluate treatment and posttreatment tooth movements. The results showed that irregularity, as measured by the irregularity index, decreased 5.3 mm during treatment and increased 0.7 mm (SD 1.1 mm) during the posttreatment period. Eighty percent of the patients had satisfactory (<3.5 mm) mandibular incisor alignment over 10 years postretention, and none was in the severe category (>6.5 mm). Mandibular intercanine width increased (1.7 mm) during treatment, whereas intermolar width decreased (-2.1 mm). Maxillary molar widths remained unchanged posttreatment, and mandibular intercanine width decreased 1.4 mm from immediately posttreatment to postretention. Arch lengths decreased during treatment because of molar protraction and incisor retraction. Mandibular arch length continued to decrease posttreatment (-1.4 mm) because of mesial molar movement rather than distal incisor movement. Satisfactory long-term results can be achieved for most Class I, 4-premolar-extraction patients for whom evidence-based treatment objectives-including minimal alteration of the mandibular arch form and the retraction and uprighting or maintenance of mandibular incisors in their original position-have been met.

Ligas ortodônticas correntemente em uso: revisão (Parte I) / Alloys currently used in Orthodontics: a review (Part I)

Revisão sobre as ligas ortodônticas corretamente em uso, em duas partes. Nesta primeira parte são abordados os tipos de testes de laboratório com os fios, salientando as propriedades de relevância clínica. As ligas consideradas são as de aço inoxidável, cromo-cobalto, níquel-titânio e beta-titânio