Dual and opposing roles of primary cilia in medulloblastoma development.

Recent work has shown that primary cilia are essential for Hedgehog (Hh) signaling during mammalian development. It is also known that aberrant Hh signaling can lead to cancer, but the role of primary cilia in oncogenesis is not known. Cerebellar granule neuron precursors (GNPs) can give rise to medulloblastomas, the most common malignant brain tumor in children. The primary cilium and Hh signaling are required for GNP proliferation. We asked whether primary cilia in GNPs have a role in medulloblastoma growth in mice. Genetic ablation of primary cilia blocked medulloblastoma formation when this tumor was driven by a constitutively active Smoothened protein (Smo), an upstream activator of Hh signaling. In contrast, removal of cilia was required for medulloblastoma growth by a constitutively active glioma-associated oncogene family zinc finger-2 (GLI2), a downstream transcription factor. Thus, primary cilia are either required for or inhibit medulloblastoma formation, depending on the initiating oncogenic event. Remarkably, the presence or absence of cilia was associated with specific variants of human medulloblastomas; primary cilia were found in medulloblastomas with activation in HH or WNT signaling but not in most medulloblastomas in other distinct molecular subgroups. Primary cilia could serve as a diagnostic tool and provide new insights into the mechanism of tumorigenesis

Effect of Mechanical Deformation on in Vitro Calcification of Segmented Polyurethane

To investigate why calcification is accelerated by mechanical flexure, in vitro calcification of segmented polyurethane (SPU) under static elongation and dynamic mechanical flexure was performed. After the calcification period, the amount of calcium deposition was increased by elongation, but the amount of calcium deposition per unit area of the elongated surface was relatively smaller as compared to that of the severe flexing area. Although the surface calcium concentration of the elongated SPU was relatively smaller than the flexed area, there was the increase of surface area by the elongation. The total amount of deposited calcium on the elongated SPU was increased as it is reduced to the original surface area. Therefore, the results reveal that certain changes of surface properties by the Mechanical deformation accelerate the calcium deposition onto the surface and the enlargement of surface area by the mechanical deformation results in the heavy calcification of the severe flexing area in the SPU

The Characteristics of Metallo-β-Lactamase-Producing Gram-Negative Bacilli Isolated from Sputum and Urine: A Single Center Experience in Korea

Metallo-β-lactamase (MBL) production usually results in high-level resistance to most β-lactams, and a rapid spread of MBL producing major gram-negative pathogens is a matter of particular concern worldwide. However, clinical data are scarce and most studies compared MBL producer (MP) with MBL non-producer (MNP) strains which included carbapenem susceptible isolates. Therefore, we collected clinical data of patients in whom imipenem-nonsusceptible Pseudomonas aeruginosa (PA) and Acinetobacter baumannii (AB) were isolated from sputum or urine, and investigated MBL production and the risk factors related with MBL acquisition. The antimicrobial susceptibility patterns were also compared between MPs and imipenem-nonsusceptible MNPs (INMNP). Among the 176 imipenem-nonsusceptible isolates, 12 MPs (6.8%) were identified. There was no identifiable risk factor that contributed to the acquisition of MPs when compared to INMNPs, and case-fatalities were not different between the two groups. The percentage of susceptible isolates was higher among MPs for piperacilin/tazobactam and fluoroquinolones while that of ceftazidime was higher in INMNPs (p < 0.05). As regards to aztreonam, which has been known to be a uniquely stable β-lactam against MBLs, susceptibility was preserved in only two isolates (16.7%) among MPs, and was not higher than that of INMNPs (23.2%). In conclusion, the contribution of MBLs to imipenem non-susceptibility in PA/ABs isolated from sputum and urine was relatively limited, and there was no significant risk factor associated with acquisition of MPs compared with INMNPs. However, limited susceptibility to aztreonam implies that MPs may hold additional resistance mechanisms, such as extended spectrum β-lactamases, AmpC β-lactamases, or other non-enzymatic mechanisms

Effects of Thermal and Humidity Aging on the Interfacial Adhesion of Polyketone Fiber Reinforced Natural Rubber Composites

Polyketone fiber is considered as a reinforcement of the mechanical rubber goods (MRG) such as tires, automobile hoses, and belts because of its high strength and modulus. In order to apply it to those purposes, the high adhesion of fiber/rubber interface and good sustainability to aging conditions are very important. In this study, polyketone fiber reinforced natural rubber composites were prepared and they were subjected to thermal and humidity aging, to assess the changes of the interfacial adhesion and material properties. Also, the effect of adhesive primer treatment, based on the resorcinol formaldehyde resin and latex (RFL), of polyketone fiber for high interfacial adhesion was evaluated. Morphological and property changes of the rubber composites were analyzed by using various instrumental analyses. As a result, the rubber composite was aged largely by thermal aging at high temperature rather than humidity aging condition. Interfacial adhesion of the polyketone/NR composites was improved by the primer treatment and its effect was maintained in aging conditions

Factors Affecting Willingness to Undergo Carpal Tunnel Release

Background: Factors regarding patient willingness to undergo or avoid joint replacement have been studied; however, these factors have not been studied in patients with carpal tunnel syndrome. To further understand the aspects that are important for a patient with carpal tunnel syndrome in deciding whether to have surgery, we identified factors that affect this decision in women and that are not related to Workers` Compensation status. Methods: We retrospectively reviewed 282 female patients with electrophysiologically confirmed carpal tunnel syndrome without a known cause who were recommended for carpal tunnel release by a single hand surgeon in a tertiary medical setting. Of those, thirty-six female patients who were not entitled to Workers` Compensation canceled the operation during the waiting period, which averaged four weeks. Thirty-three of them were surveyed with a questionnaire sent by mail, and eighteen completed surveys were reviewed at a mean follow-up of thirty-two months. Furthermore, seventy female patients who underwent carpal tunnel release were randomly sampled, and thirty-eight patients completed the survey. The operation and cancellation groups were compared with regard to the reasons for choosing or canceling surgery. Results: The groups were similar with regard to age, sociodemographic variables, follow-up length, initial electro-physiological findings, and functional status. The highest-ranked reason for choosing surgery was symptom severity rather than fear of progression or a positive electrodiagnostic result. Those who canceled the operation rated symptom improvement during the waiting period as the leading reason for doing so, but they were also concerned about transient weakness, the financial burden, and a scar or pillar pain. Disease persistence or recurrence was the issue of most concern in both groups. At the time of the final review, the functional status was significantly improved in both groups and no significant difference between the groups was detected. Conclusions: Women with carpal tunnel syndrome report that subjective symptom severity is the most important reason for undergoing surgery. Understanding this and other patient concerns may help physicians during patient-oriented consultation and decision-making. In particular, recommendations for carpal tunnel release on the basis of symptoms are reasonable from the perspective of the patient who has carpal tunnel syndrome without a known cause.Lee JY, 2008, J SHOULDER ELB SURG, V17, P570, DOI 10.1016/j.jse.2007.12.005Hudak PL, 2008, J BONE JOINT SURG AM, V90A, P1427, DOI 10.2106/JBJS.G.01077Park KK, 2007, CLIN ORTHOP RELAT R, P143, DOI 10.1097/BLO.0b013e31804ea0bcTaylor-Gjevre RM, 2007, CAN FAM PHYSICIAN, V53, P1186Rigler I, 2007, EUR J NEUROL, V14, P783, DOI 10.1111/j.1468-1331.2007.01855.xBallantyne PJ, 2007, ARTHRIT RHEUM-ARTHR, V57, P27, DOI 10.1002/art.22472*AAOS CARP TUNN SY, 2007, AM AC ORTH SURG GUIDSCHOLTEN RJ, 2007, COCHRANE DB SYST REV, V17, P3905Hawker GA, 2006, CURR OPIN RHEUMATOL, V18, P526Mazur DJ, 2005, HEALTH EXPECT, V8, P97FIGARO MK, 2005, J AMBUL CARE MANAGE, V28, P41Hawker GA, 2004, ARTHRIT RHEUM-ARTHR, V51, P635, DOI 10.1002/art.20524Figaro MK, 2004, HEALTH PSYCHOL, V23, P324, DOI 10.1037/0278-6133.23.3.324Chang HJ, 2004, ARTHRIT RHEUM-ARTHR, V51, P117, DOI 10.1002/art.20073AKELMAN E, 2004, HAND SURG, P867Moran M, 2003, J ARTHROPLASTY, V18, P442, DOI 10.1016/S0883-5403(03)00061-5RESENDE LA, 2003, ELECTROMYOGR CLIN NE, V43, P301Ang DC, 2002, MED CARE, V40, P471Hawker GA, 2001, MED CARE, V39, P206Bland JDP, 2000, MUSCLE NERVE, V23, P1280Trousdale RT, 1999, MAYO CLIN PROC, V74, P978Atroshi I, 1999, JAMA-J AM MED ASSOC, V282, P153Homan MM, 1999, SCAND J WORK ENV HEA, V25, P115Padua L, 1998, ITAL J NEUROL SCI, V19, P357Aulisa L, 1998, J HAND SURG-AM, V23A, P687Nathan PA, 1998, MUSCLE NERVE, V21, P711Concannon MJ, 1997, PLAST RECONSTR SURG, V100, P1452Asch DA, 1997, J CLIN EPIDEMIOL, V50, P1129Hudak PL, 1996, AM J IND MED, V30, P372Deber RB, 1996, ARCH INTERN MED, V156, P1414Hudak PL, 1996, AM J IND MED, V29, P602WRIGHT JG, 1994, J BONE JOINT SURG BR, V76B, P229LEVINE DW, 1993, J BONE JOINT SURG AM, V75A, P1585SIMINOFF LA, 1991, SOC SCI MED, V32, P813GRUNDBERG AB, 1983, J HAND SURG-AM, V8, P348

Clinical Review of Endogenous Endophthalmitis in Korea: A 14-Year Review of Culture Positive Cases of Two Large Hospitals

PURPOSE: To identify the clinical features and outcomes of endogenous endophthalmitis in Korea. MATERIALS AND METHODS: We reviewed 18 patients with endogenous endophthalmitis at 2 Korean hospitals, treated over a 14 year period between January 1993 and December 2006. RESULTS: The comorbidities observed in these cases were diabetes mellitus and liver cirrhosis. The most common pathogens, which were found in 7 patients each (38.9%), were Klebsiella pneumonia and Pseudomonas aeruginosa. All patients were treated with systemic antibiotics and fortified topical antibiotics. A surgical approach including vitrectomy was performed in 9 cases (50.0%). The prognosis was generally poor, and visual acuity improved slightly in 6 patients (33.3%). CONCLUSION: In this study, diabetes mellitus and Klebsiella pneumonia showed a close relationship with endogenous endophthalmitis, respectively. Endogenous endophthalmitis is a serious risk to sight and careful attention to establishing the diagnosis and management may decrease the ocular morbidity.ope

Modified Bilhaut-Cloquet procedure for Wassel type-II and III polydactyly of the thumb. Surgical technique

BACKGROUND: The Bilhaut-Cloquet operation is a combined surgical procedure for the treatment of a symmetric bifid thumb. Although this procedure can obtain a normal-sized thumb with a stable interphalangeal joint, it has limitations, such as the technical difficulty of combining all segments of a duplicated thumb, possible later physeal growth arrest, joint stiffness, and nail plate deformity. We reviewed the results of our modification of this procedure for the treatment of Wassel type-II and III polydactyly of the thumb. METHODS: Seven patients, two with type-II and five with type-III polydactyly of the thumb, underwent this modified Bilhaut-Cloquet procedure and were followed for an average of fifty-two months. Cosmetic and functional assessments were made. RESULTS: All patients and parents were satisfied with the cosmetic and functional results. Compared with the preoperative motion, the postoperative range of motion of the interphalangeal joint was preserved in thumbs with type-III deformity and was increased in those with type-II deformity. No nail deformity or growth arrest occurred, and remodeling and hypertrophy of the distal phalanx occurred with time. CONCLUSIONS: Our modification of the Bilhaut-Cloquet procedure for the treatment of type-II and III thumb polydactyly is effective in preserving interphalangeal joint motion, minimizing nail deformity, and preventing growth arrest