Biomechanical evaluation of the impact of collared cementless total hip arthroplasty stems on implant subsidence: a cadaveric study in German Shepherd.

Background: With the increasing use of cementless total hip arthroplasty (THA), stem subsidence has emerged as one of the primary complications. Although electron beam melting (EBM)-manufactured stems have been demonstrated to prevent subsidence, there has been limited investigation into the comparative biomechanical impact of collarless and collared EBM cementless stems on stem subsidence in veterinary medicine. Aims: This study aimed to compare the stem implant resistance and failure mechanical properties between collarless and collared EBM-manufactured stems. Methods: Seven pairs of femurs were harvested from canine cadavers. In each pair of femurs, the left femur was implanted with a collarless, and the right femur with a same-sized collared cementless stem. Specimen constructs were mounted to the loading frame of a testing machine and load was transferred to the femoral stem parallel to the longitudinal axis of the femur until the stem subsided 5 mm. Load and stem displacement data acquired during the tests were used to generate load-displacement curves and obtain stiffness, yield, and failure data for each specimen construct. Yield and failure energies were calculated as the areas under the load-displacement curves to the respective points. The effects of implant type and load during subsidence were analyzed using paired t-tests. Results: The yield and failure loads for the collared stems were approximately 40% greater than for the collarless stems (156.39 ± 43.63 kgf vs. 112.01 ± 59.83 kgf, P<0.05). Conclusion: This study supported the advantages of collared EBM stems, including subsidence prevention and better initial stability for early osteointegration.

Anterior resection syndrome: a randomized clinical trial of a 5-HT3 receptor antagonist (ramosetron) in male patients with rectal cancer.

BACKGROUND: No effective treatment exists for anterior resection syndrome (ARS) following sphincter-saving surgery for rectal cancer. This RCT assessed the safety and efficacy of a 5-HT3 receptor antagonist, ramosetron, for ARS. METHODS: A single-centre, randomized, controlled, open-label, parallel group trial was conducted. Male patients with ARS 1 month after rectal cancer surgery or ileostomy reversal were enrolled and randomly assigned (1 : 1) to 5 µg of ramosetron (Irribow®) daily or conservative treatment for 4 weeks. Low ARS (LARS) score was calculated after randomization and 4 weeks after treatment. The study was designed as a superiority test with a primary endpoint of the proportion of patients with major LARS between the groups. Primary outcome analysis was based on the modified intention-to-treat population. Safety was assessed by monitoring adverse events during the study. RESULTS: : A total of 100 patients were randomized to the ramosetron (49 patients) or conservative treatment group (51 patients). Two patients were excluded, and 48 and 50 patients were analysed in the ramosetron and control groups, respectively. The proportion of major LARS after 4 weeks was 58 per cent (28 of 48 patients) in the ramosetron group versus 82 per cent (41 of 50 patients) in the control group, with a difference of 23.7 per cent (95 per cent c.i. 5.58 to 39.98, P = 0.011). There were minor adverse events in five patients, which were hard stool, frequent stool or anal pain. These were not different between the two groups. There were no serious adverse events. CONCLUSION: : Ramosetron could be safe and feasible for male patients with ARS. TRIAL REGISTRATION NUMBER: NCT02869984 (http://www.clinicaltrials.gov).

High tuberculosis transmission rate in children with nursery exposure to undetected pulmonary tuberculosis.

SETTING: Nursery for newborns in Busan, Republic of Korea. OBJECTIVE: To evaluate tuberculosis (TB) transmission from a health care worker with active pulmonary TB to neonatal contacts. DESIGN: For the first investigation, infants who had been in the nursery 3 months before the index patient was diagnosed with pulmonary TB were enrolled. After a child who had stayed in the nursery 10 months before the diagnosis of the index patient was diagnosed with tuberculous meningitis, a second contact investigation was conducted. RESULTS: Respectively 315 and 1334 children participated in the first and second investigations. The mean age of the contacts was 66.3 days; the rate of latent tuberculous infection (LTBI) at the first investigation was 42.5% (134/315). Only one infant had an abnormal chest X-ray, and was thought to have pulmonary TB. In the second investigation, the mean age of the participants was 17.6 months. The proportion of children with LTBI was 18.7% (249/1334). CONCLUSIONS: The LTBI rate in the present study was much higher than that estimated from other contact investigations. To minimise the risk of nosocomial TB transmission to neonates, screening and management of TB in health care workers should be strengthened.

Ultrasonic-assisted synthesis of ZnTe nanostructures and their structural, electrochemical and photoelectrical properties.

Colloidal zinc telluride (ZnTe) nanostructures were successfully processed through a simple and facile ultrasonic (sonochemical) treatment for photoelectronic applications. The particle-like morphological features, phase and nature of valence state of various metal ions existing in ZnTe were examined using electron and X-ray photoelectron spectroscopic tools. Raman spectroscopic measurements revealed the dominance of exciton-phonon coupling and occurrence of TeO2 traces in ZnTe through the corresponding vibrations. Optical bandgap of the ZnTe suspension was estimated to be around 2.15eV, authenticating the direct allowed transitions. The p-type electrical conductivity and charge carrier density of ZnTe were additionally estimated from the Bode, Nyquist and Mott-Schottky type impedance plots. The photoelectrical properties of ZnTe were investigated by fabricating p-ZnTe/n-Si heterostructures and studying their corresponding current-voltage characteristics under dark and white light illumination. The diodes revealed excellent rectifying behaviour with significant increase in reverse current under illumination. The stability of the devices were also affirmed through the time-dependent photoresponse characteristics, which actually suggested the improved and effective separation of photo generated electron hole pairs across the integrated heterojunctions. The obtained results also augment the potential of sonochemically processed ZnTe for application in photo detection and sensor related functions.

Biomechanical characteristics of self-ligating brackets in a vertically displaced canine model: a finite element analysis.

OBJECTIVES: The objective of this study was to compare the biomechanical characteristics between two types of self-ligating brackets and conventional metal brackets using finite element analysis of a vertically displaced canine model focusing on the desired force on the canine and undesirable forces on adjacent teeth. MATERIALS AND METHODS: Three-dimensional finite element models of the maxillary dentition with 1-mm, 2-mm, and 3-mm vertically displaced canines were constructed. Two different self-ligating brackets (In-Ovation C and Smart clip) and a conventional metal bracket (Micro-arch) were modeled. After a 0.016-inch NiTi (0.40 mm, round) wire was engaged, the displacement of each tooth was calculated using x-, y-, and z-coordinates, and the tensile and compressive stresses were calculated. RESULTS: The extrusion and maximal tensile stress of the canine differed little between the three brackets, but the intrusion and minimal compressive stress values of the adjacent teeth differed considerably and were highest in the Smart clip and least in the In-Ovation C. The extrusion and maximal tensile stress of the canine in the 3-mm displacement model was less than that in the 2-mm displacement model, and the intrusion and minimal compressive stress of the adjacent teeth increased with the degree of displacement. CONCLUSIONS: Self-ligating brackets were not superior to conventional brackets in leveling a vertically displaced canine. A continuous arch wire may not be recommended for leveling of severely displaced canines whether using self-ligating or conventional brackets.

Retinal pigment epithelial cells undergoing mitotic catastrophe are vulnerable to autophagy inhibition.

The increased mitochondrial DNA damage leads to altered functional capacities of retinal pigment epithelial (RPE) cells. A previous study showed the increased autophagy in RPE cells caused by low concentrations of rotenone, a selective inhibitor of mitochondrial complex I. However, the mechanism by which autophagy regulates RPE cell death is still unclear. In the present study, we examined the mechanism underlying the regulation of RPE cell death through the inhibition of mitochondrial complex I. We report herein that rotenone induced mitotic catastrophe (MC) in RPE cells. We further observed an increased level of autophagy in the RPE cells undergoing MC (RPE-MC cells). Importantly, autophagy inhibition induced nonapoptotic cell death in RPE-MC cells. These findings indicate that autophagy has a pivotal role in the survival of RPE-MC cells. We next observed PINK1 accumulation in the mitochondrial membrane and parkin translocation into the mitochondria from the cytosol in the rotenone-treated RPE-MC cells, which indicates that increased mitophagy accompanies MC in ARPE-19 cells. Noticeably, the mitophagy also contributed to the cytoprotection of RPE-MC cells. Although there might be a significant gap in the roles of autophagy and mitophagy in the RPE cells in vivo, our in vitro study suggests that autophagy and mitophagy presumably prevent the RPE-MC cells from plunging into cell death, resulting in the prevention of RPE cell loss.

Failure of Helicobacter pylori eradication and age are independent risk factors for recurrent neoplasia after endoscopic resection of early gastric cancer in 283 patients.

BACKGROUND: Whether the incidence of metachronous gastric dysplasia and cancer could be decreased by eradication of Helicobacter pylori after endoscopic submucosal dissection (ESD) for early gastric cancer (EGC). AIM: To compare the incidence of metachronous gastric lesion in the eradicated group and the persistent group. Second end point is to evaluate the risk factors for metachronous gastric lesions after ESD for EGC. METHODS: In a single centre, between May 2007 and May 2010, the patients who had evidence of H. pylori infection at the time of ESD for EGC were included, and the follow-up data were analysed retrospectively. RESULTS: We enrolled 283 patients who have shown H. pylori infection at the time of ESD for EGC. Successful eradication was achieved for 214 patients (75.6%) (Eradicated group), and 69 patients (24.4%) showed persistent H. pylori infection (Persistent group). Metachronous gastric lesions developed in 13 (18.8%) in the persistent group and 18 (8.4%) in the eradicated group (P = 0.016). In the ≥60-year-old group, the cumulative incidence of metachronous gastric cancer showed a significant increase (P = 0.012). Cumulative hazard ratio of subsequent gastric metachronous lesions differed between the eradication group and the persistent infection group (OR = 2.322, 95% CI = 1.136-4.744, P = 0.021), and ≥60 age at the time of endoscopic resection (OR = 2.803, 95% CI = 1.207-6.509, P = 0.016). CONCLUSIONS: Both persistent H. pylori infection and old age (≥60) are independent risk factors for the increased incidence of metachronous gastric cancer.

Diffusion tensor imaging-demonstrated differences between hemiplegic and diplegic cerebral palsy with symmetric periventricular leukomalacia.

BACKGROUND AND PURPOSE: Patients with cerebral palsy have variable clinical presentations such as hemiplegic, diplegic, or quadriplegic patterns though they have PVL on conventional MR images. The authors investigated whether DTT can differentiate between hemiplegic and diplegic CP in patients presenting with symmetric PVL on conventional MR images. MATERIALS AND METHODS: One hundred thirteen consecutive pediatric patients with definite hemiplegic (59 patients; 30 boys, 29 girls; mean age, 34.19 months; range, 24-52 months) or diplegic (54 patients; 27 boys, 27 girls; mean age, 31.07 months; range, 24-48 months) symptoms and bilateral symmetric PVL on conventional brain MR imaging were recruited. The states of CSTs were examined by using DTT, and the asymmetries of right and left CSTs in the hemiplegic and diplegic groups were compared by using asymmetric anisotropy indexes and asymmetric mean diffusivity indexes. RESULTS: All patients in the hemiplegic group with asymmetric results exhibited disrupted integrities of more affected CSTs and sparing of less affected CSTs. However, diplegic patients revealed symmetric disrupted findings of the right and left CSTs at the upper periventricular level. Asymmetric anisotropy index and asymmetric mean diffusivity index values were significantly higher in the hemiplegic group than in the diplegic group (P < .05), and these results of DTT significantly corresponded with their typical clinical manifestation. CONCLUSIONS: DTT may be very useful for the detailed estimation of the CST state in patients with bilateral symmetric PVL.

Heat transfer and pressure drop characteristics of nanofluids in a plate heat exchanger.

In this paper, the heat transfer characteristics and pressure drop of the ZnO and Al2O3 nanofluids in a plate heat exchanger were studied. The experimental conditions were 100-500 Reynolds number and the respective volumetric flow rates. The working temperature of the heat exchanger was within 20-40 degrees C. The measured thermophysical properties, such as thermal conductivity and kinematic viscosity, were applied to the calculation of the convective heat transfer coefficient of the plate heat exchanger employing the ZnO and Al2O3 nanofluids made through a two-step method. According to the Reynolds number, the overall heat transfer coefficient for 6 vol% Al2O3 increased to 30% because at the given viscosity and density of the nanofluids, they did not have the same flow rates. At a given volumetric flow rate, however, the performance did not improve. After the nanofluids were placed in the plate heat exchanger, the experimental results pertaining to nanofluid efficiency seemed inauspicious.

Novel drug delivery systems for glaucoma.

Reduction of intraocular pressure (IOP) by pharmaceutical or surgical means has long been the standard treatment for glaucoma. A number of excellent drugs are available that are effective in reducing IOP. These drugs are typically applied as eye drops. However, patient adherence can be poor, thus reducing the clinical efficacy of the drugs. Several novel delivery systems designed to address the issue of adherence and to ensure consistent reduction of IOP are currently under development. These delivery systems include contact lenses-releasing glaucoma medications, injectables such as biodegradable micro- and nanoparticles, and surgically implanted systems. These new technologies are aimed at increasing clinical efficacy by offering multiple delivery options and are capable of managing IOP for several months. There is also a desire to have complementary neuroprotective approaches for those who continue to show progression, despite IOP reduction. Many potential neuroprotective agents are not suitable for traditional oral or drop formulations. Their potential is dependent on developing suitable delivery systems that can provide the drugs in a sustained, local manner to the retina and optic nerve. Drug delivery systems have the potential to improve patient adherence, reduce side effects, increase efficacy, and ultimately, preserve sight for glaucoma patients. In this review, we discuss benefits and limitations of the current systems of delivery and application, as well as those on the horizon.

Orientational relationships and atomic arrangements of GaN nanorods grown on Al2O3 (0001) substrates by using hydride vapor phase epitaxy.

Scanning electron microscopy (SEM) images and transmission electron microscopy (TEM) images showed that the one-dimensional GaN nanorods were formed on Al2O3 (0001) substrates by using hydride vapor phase epitaxy without a catalyst. Selected area electron diffraction (SAED) pattern and high-resolution TEM (HRTEM) results showed that GaN nanorods grown on Al2O3 (0001) substrates had crystalline wurzite structures and (0001) preferential orientation. The morphologies of GaN nanorods were affected by the flow rates of the source materials. The orientational relationships between the GaN nanorods and the Al2O3 substrates were (0001)GaN perpendicular (0001) Al2O3 and [0110]GaN perpendicular [1120] Al2O3. Cross-sectional and plan-view atomic arrangements of the fully relaxed interfacial region are described on the basis of the TEM, the SAED pattern, and the HRTEM results.

Morphology of deltoid origin and end tendons--a generic model.

This study provides a model of the complex deltoid origin and end tendons, as a basis for further anatomical, biomechanical and clinical research. Although the deltoid is used in transpositions with upper limb paralysis, its detailed morphology and segmentation has not been object of much study. Morphologically, the deltoid faces two distinct challenges. It closely envelops a ball joint, and it reduces its width over a short distance from a very wide origin along clavicle, acromion and spina scapula, to an insertion as narrow as the humerus. These challenges necessitate specific morphological tendon adaptations. A qualitative model for these tendons is developed by the stepwise transformation of a unipennate muscle model into a functional deltoid muscle. Each step is the solution to one of the mentioned morphological challenges. The final model is of an end tendon consisting of a continuous succession of bipennate end tendon blades centrally interspaced by unipennate tendon parts. The origin tendon consists of lamellae that interdigitate with the end tendon blades, creating a natural segmentation. The model is illustrated by qualitative dissection results. In addition, in view of a proliferation of terms found in the literature to describe deltoid tendons, tendon concepts are reviewed and the systematic use of the unique and simple terminology of 'origin and end tendons' is proposed.

Kernohan's notch phenomenon demonstrated by diffusion tensor imaging and transcranial magnetic stimulation.

Kernohan's notch phenomenon is the ipsilateral hemiplegia caused by compression of the contralateral cerebral peduncle against the tentorial edge by a supratentorial mass. Diffusion tensor imaging (DTI) and transcranial magnetic stimulation (TMS) could be useful for exploring the state of the corticospinal tract (CST). This report attempts to demonstrate Kernohan's notch phenomenon in a patient with subdural haematoma by using DTI and TMS. One patient and six normal control subjects were recruited. The patient showed severe right hemiplegia even though the subdural haematoma was located in the right hemisphere. Brain CT at the time of onset showed right transtentorial herniation, and T2 weighted images at 6 weeks after onset showed a leucomalacic lesion on the left cerebral peduncle. DTI and TMS were performed at 6 weeks after onset. The fractional anisotrophy value of the left midbrain and medulla of the patient was found to be decreased in comparison with that of the control subjects. On fibre tractography for the CST, an interruption was observed in the left midbrain and medulla. The motor evoked potential obtained from the right hand muscle showed delayed latency, low amplitude and a higher excitatory threshold, thus indicating that the CST of the left hemisphere had been damaged. It seems that the CST had been damaged at the left midbrain, although subdural haematoma and transtentorial herniation had occurred in the right hemisphere in this patient. This report demonstrates Kernohan's notch phenomenon in this patient using DTI and TMS.

Photodetection of basal cell carcinoma using methyl 5-aminolaevulinate-induced protoporphyrin IX based on fluorescence image analysis.

BACKGROUND: The preferential accumulation of 5-aminolaevulinic acid (ALA)-induced protoporphyrin IX (PpIX) in neoplastic cells supports its potential use in the photodetection of porphyrin fluorescence in tumour cells. Hence, epithelial tumours, including basal cell carcinoma (BCC), might be visualized using the fluorescence of selectively accumulated ALA-induced PpIX. AIM: In this study, we evaluated the clinical efficacy of PpIX fluorescence images using fluorescence image analysis (FIA) to define the lateral border between the tumour and tumour-free areas of facial BCC. METHODS: FIA was used to define the lateral border between the tumour and tumour-free areas on red fluorescence images induced by the topical application of methyl 5-aminolaevulinate (MAL) ointment. According to the FIA results, 50 tissue samples, obtained from 10 patients with BCC, were divided into three categories: tumour area (n = 10), suspected tumour area (n = 20) and suspected tumour-free area (n = 20). These tissue samples were evaluated by histopathological examination. The FIA tool marked out the PpIX fluorescence image for defining the lateral border between the BCC tumour and tumour-free areas. RESULTS: The rate of tumour detection from BCC lesions using PpIX fluorescence with the FIA tool showed a sensitivity of 94.1% and specificity of 82.6%. CONCLUSION: These results suggest that MAL-induced PpIX fluorescence imaging using FIA is quite sensitive and specific for detecting tumour and occult tumour in facial BCC lesions. This method of presurgical in vivo imaging is therefore proposed as a useful tool for defining the lateral border between BCC tumour and tumour-free areas.

Evaluation of polymerization in fluoride-containing composite resins.

Fluoride-containing restorative materials are frequently utilized to delay or inhibit caries. The quality of the fluoride-containing composite resins was evaluated by testing their microhardness, polymerization shrinkage, thermal expansion coefficient, and surface morphology. Some of them were evaluated in conjunction with the thermocycling process. The microhardness values of the thermocycled specimens were similar to those of the specimens immersed only in distilled water. Among the specimens, Surefil showed the highest (68.6 +/- 1.2 Hv) value. A linear correlation was found between microhardness and the filler content (vol%) of the specimens regardless of their states. Polymerization shrinkage rapidly increased during the light curing, and then it reached a plateau. The shrinkage values increased as the specimens became thicker. In a temperature range of 30 approximately 80 degrees C, the coefficients of thermal expansion of the control specimens ranged between 43 x 10(-6)/ degrees C and 77 x 10(-6)/ degrees C. An inverse correlations were observed between the filler content (vol%) and the coefficient of thermal expansion and between microhardness and the coefficient of thermal expansion of the control specimens. Tetric Ceram showed a perforated or "Swiss-cheese" morphology after thermocycling. It was unique and occurred only in this product.

Intraocular pressure measurement in mice: a comparison between Goldmann and rebound tonometry.

PURPOSE: The development of mouse models of glaucoma requires methods to accurately measure the intraocular pressure (IOP) in this species. The aim of this study was to compare the accuracy of IOP measurements in mice between modified Goldmann and rebound tonometers. METHODS: IOP was measured either with a modified Goldmann or a rebound tonometer while simultaneously measuring the IOP using invasive manometry in enucleated eyes and in vivo. The level of IOP was controlled hydrostatically. The agreement and correlation between the IOP determined by invasive manometry and by either noninvasive method was evaluated. In addition, the IOP was determined by both noninvasive methods in a cohort of mice with laser-induced ocular hypertension (OHT), and the agreement and correlation between the two tonometry methods were evaluated. RESULTS: Measured IOP by either noninvasive tonometer correlated well with those recorded simultaneously by invasive manometry (r=0.98 for rebound and r=0.94 for Goldmann). In mice with OHT, the IOP correlation between rebound and modified Goldmann was moderate (r=0.71); the IOP measured by modified Goldmann tonometry was consistently higher than that by rebound by approximately 5 mmHg. However, the relative per cent increases in IOP were similar between the two methods. CONCLUSION: Both noninvasive methods of IOP measurements in mice are suitable to detect changes in IOP although rebound tonometry correlated better with the invasive manometry readings. The results suggest that the relative, rather than absolute, IOP offers a more reliable means of correlating findings from studies using different tonometers.

Salivary cortisol, testosterone, and T/C ratio responses during a 36-hole golf competition.

The purpose of this investigation was to study the effects of 36 continuous holes of competitive golf on salivary testosterone, cortisol, and testosterone-to-cortisol ratio and their relation to performance in eight elite male collegiate golfers (age 20.3 [+/- 1.5] years). Thirty-six holes of a 54-hole NCAA golf tournament were played on the first day of the competition. A saliva sample was taken 45 minutes prior to the round and immediately following each hole for a total of 37 samples per subject. Time matched baseline samples were collected on a different day to account for circadian variation. Six-hole areas under the curve (AUC) values were calculated for endocrine measures. Significant (p < 0.05) increases were noted for cortisol during competition, however, testosterone did not change during competition compared to baseline. Testosterone-to-cortisol (T/C) ratio was significantly lower throughout the competition compared to baseline measures. Thirty-six-hole AUC testosterone-to-cortisol ratio response was correlated (r = 0.82) to 36-hole score. There was a high correlation between pre-round testosterone (r = 0.71), T/C ratio response (r = 0.82), and 36-hole score. CSAI-2 somatic anxiety was correlated to pre-round cortisol (r = 0.81) and testosterone (r = - 0.80) response. These results indicate a significant hormonal response during 10 hours of competitive golf. Good golf performance (low golf scores) in this competition was related to low T/C ratio (r = .82). Additionally, results from this investigation validated CSAI-2 somatic anxiety with physiological measures of anxiety.

Longitudinal fMRI study for locomotor recovery in patients with stroke.

The authors investigated bihemispheric motor network reorganization supporting locomotor recovery after stroke over time. They determined longitudinal changes in locomotor function and fMRI in 10 stroke patients at the subacute stage and the chronic stage. The results suggest that the bihemispheric reorganization mechanism underlying locomotor recovery evolved from the ipsilateral (contralesional) primary sensorimotor cortex (SM1) activation at the subacute stage to the contralateral (ipsilesional) SM1 activation at the chronic stage.