Dynamical Response of Nanomechanical Resonators to Biomolecular Interactions

We studied the dynamical response of a nanomechanical resonator to biomolecular (e.g. DNA) adsorptions on a resonator's surface by using a theoretical model, which considers the Hamiltonian H such that the potential energy consists of elastic bending energy of a resonator and the potential energy for biomolecular interactions. It was shown that the resonant frequency shift of a resonator due to biomolecular adsorption depends on not only the mass of adsorbed biomolecules but also the biomolecular interactions. Specifically, for dsDNA adsorption on a resonator's surface, the resonant frequency shift is also dependent on the ionic strength of a solvent, implying the role of molecular interactions on the dynamic behavior of a resonator. This indicates that nanomechanical resonators may enable one to quantify the biomolecular mass, implying the enumeration of biomolecules, as well as gain insight into intermolecular interactions between adsorbed biomolecules on the surface.Comment: 17 page, 4 figures, accepted for publication at PRB. Physical Review B, accepte

The Effect of Neuromuscular Blockade Reversal Agents on Postoperative Pulmonary Complications in Patients undergoing Femur Fracture Repair Surgery: A Retrospective Observational Study

Background Femoral fracture repair surgery under general anesthesia is associated with postoperative pulmonary complications (PPCs). However, information on PPCs caused by residual neuromuscular blockade following perioperative use of neuromuscular blockers is limited. This study aimed to identify the differences in the incidence of PPCs according to the type of neuromuscular blockade reversal agent used in femoral fracture repair surgery, as well as the risk factors for PPCs. Methods We retrospectively analyzed the electronic medical records of 604 patients aged >18 years who underwent general anesthesia for femoral fracture repair surgery at a single university hospital between March 2017 and March 2022. Patients in whom sugammadex or anticholinesterase was used to reverse the neuromuscular block were subjected to propensity score matching. Multivariate logistic regression analysis was performed to identify risk factors for PPCs. Results Among the 604 patients, 108 were matched in each group. The incidence rates of PPCs overall and in the anticholinesterase and sugammadex groups were 7.0%, 8.3%, and 5.6%, respectively, with no significant differences between the groups. Older age, higher ASA (American Society of Anesthesiologists) physical status, and lower preoperative oxygen saturation were risk factors, whereas emergency surgery was a preventive factor. Conclusions Our results demonstrated that the incidence of PPC did not differ significantly between sugammadex and anticholinesterase in patients undergoing femur fracture repair under general anesthesia. Identifying the risk factors and confirming complete recovery from neuromuscular blockade might be more important

Microstructures and Electrochemical Behavior of Ti-Mo Alloys for Biomaterials

The Ti alloy with 7 wt% Mo revealed a microstructure that contained only the orthorhombic α′′ phase of a fine acicular martensitic structure. The corrosion resistance of the Ti-Mo alloys increased as the Mo content increased. Based on the results obtained from the polarization curve and electrochemical impedance, the Ti-Mo alloys were shown to be corrosion resistant because of the passive films formed on their surfaces. No ion release was detected in SBF (simulated body fluid) solution, while Ti ions were released in 0.1% lactic acid ranging from 0.05 to 0.12 μg/mL for the Ti-Mo alloys. In vitro tests showed that MC3T3-E1 cell proliferation on Ti-7 wt% Mo alloy was rather active compared to other Ti-Mo alloys and commercial-grade pure Ti

Antiosteoporosis Activity of New Oriental Medicine Preparation (Kyungokgo Mixed with Water Extract of Hovenia dulcis

Protective effect of new oriental medicine (Kyungokgo mixed with water extract of Hovenia dulcis, KOGHD) was assessed on the bone loss induced mice by ovariectomy. In the in vivo experiments, antiosteoporosis effect of KOGHD was investigated using ovariectomized osteoporosis mice model. After 6 weeks of treatment, the mice were euthanized, and the effect of Kyungokgo (KOG) and KOGHD on body weight, spleen weigh, thymus weight, uterine weight, serum biochemical indicators, bone weight and length, immune cell population, bone morphometric parameters, and histological stains was observed. Our results showed that KOGHD prevented the deterioration of trabecular microarchitecture caused by ovariectomy, which were accompanied by the lower levels of bone turnover markers and immune cell population as evidenced by the inhibition of RANKL-mediated osteoclast differentiation without cytotoxic effect on bone marrow derived macrophages (BMMs). Therefore, these results suggest that the Hovenia dulcis (HD) supplementation in the KOG may also prevent and treat bone loss

Arrhythmia surgery for atrial fibrillation associated with atrial septal defect: Right-sided maze versus biatrial maze

BackgroundAlthough it has been inferred that a biatrial maze procedure for atrial fibrillation in left-sided heart lesions may lead to better outcomes compared with a limited left atrial lesion set, it remains controversial whether the biatrial maze procedure is superior to the right atrial maze procedure in right-sided heart lesions.MethodsA retrospective review was performed for 56 adults who underwent surgical closure of atrial septal defect and various maze procedures for atrial fibrillation between June 1998 and February 2011. The median age at operation was 59 years (range, 34-79 years). Clinical manifestations of atrial fibrillation were paroxysmal in 8 patients, persistent in 15 patients, and long-standing persistent in 33 patients. A right atrial maze procedure was performed in 23 patients (group 1), and a biatrial maze procedure was performed in 33 patients (group 2). Treatment failure was defined as atrial fibrillation recurrence, development of atrial flutter or other types of atrial tachyarrhythmia, or implantation of a permanent pacemaker. The Cox proportional hazards model was used to identify risk factors for decreased time to treatment failure.ResultsDuring the median follow-up period of 49 months (range, 5-149 months), there was no early death and 1 late noncardiac death. On Cox survival model, group 1 showed a significantly decreased time to treatment failure in comparison with group 2 (hazard ratio, 5.11; 95% confidence interval, 1.59-16.44; P = .006). Maintenance of normal sinus rhythm without any episode of atrial fibrillation recurrence at 2 and 5 years postoperatively was 57% and 45% in group 1, respectively, and 82% and 69% in group 2, respectively.ConclusionsLeft-sided ablation in addition to a right atrial maze procedure leads to better electrophysiologic outcome in atrial fibrillation associated with atrial septal defect

Identification of C16orf74 as a Marker of Progression in Primary Non-Muscle Invasive Bladder Cancer

PURPOSE: Methylation-induced silencing of PRSS3 has been shown to be significantly associated with invasive bladder cancer, and expression of the C16orf74 gene locus has been shown to correlate positively with PRSS3. The aim of the current study was to evaluate the relationship between C16orf74 expression level and progression in non-muscle invasive bladder cancer (NMIBC). MATERIALS AND METHODS: C16orf74 mRNA levels were examined by real-time reverse transcriptase polymerase chain reaction (RT-PCR) analysis of 193 tumor specimens from patients with primary NMIBC. Expression data were analyzed in terms of clinical and experimental parameters. Kaplan-Meier curves and multivariate Cox regression models, respectively, were used to determine progression-free survival and to identify independent predictive parameters of progression. RESULTS: Analysis using Kaplan-Meier curves revealed prolonged progression-free survival of high-C16orf74-expressors as compared to low-expressors (p<0.001). Multivariate Cox regression analysis revealed that low C16orf74 mRNA expression levels are a significant risk factor for disease progression in patients with primary NMIBC (HR: 10.042, CI:2.699-37.360, p = 0.001). CONCLUSIONS: Decreased expression of C16orf74 correlates significantly with progression in primary NMIBC. C16orf74 expression level represents a potentially useful marker for predicting progression in primary NMIBC patients

Optical spectroscopic investigation on the coupling of electronic and magnetic structure in multiferroic hexagonal RMnO3 (R = Gd, Tb, Dy, and Ho) thin films

We investigated the effects of temperature and magnetic field on the electronic structure of hexagonal RMnO3 (R = Gd, Tb, Dy, and Ho) thin films using optical spectroscopy. As the magnetic ordering of the system was disturbed, a systematic change in the electronic structure was commonly identified in this series. The optical absorption peak near 1.7 eV showed an unexpectedly large shift of more than 150 meV from 300 K to 15 K, accompanied by an anomaly of the shift at the Neel temperature. The magnetic field dependent measurement clearly revealed a sizable shift of the corresponding peak when a high magnetic field was applied. Our findings indicated strong coupling between the magnetic ordering and the electronic structure in the multiferroic hexagonal RMnO3 compounds.Comment: 16 pages including 4 figure

Molecular genetic study of novel biomarkers for early diagnosis of oral squamous cell carcinoma

Objectives: Early detection and treatment of an oral squamous cell carcinoma (OSCC) is critical because of its rapid growth, frequent lymph-node metastasis, and poor prognosis. However, no clinically-valuable methods of early diagnosis exist, and genetic analysis of OSCCs has yielded no biomarkers. Study D esign: We investigated the expression of genes associated with inflammation in OSCCs via a quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) analysis of microarray data. Tumor and normal tissues from five patients with an OSCC were used for microarray analysis. Differentially-expressed genes, identified using permutation, local pooled error (LPE), t-tests, and significance analysis of microarrays (SAM), were selected as candidate genetic markers. Results: Two groups corresponding to tissue identity were evident, implying that their differentially-expressed genes represented biological differences between tissues. Fifteen genes were identified using the Student’s paired t-test ( p< 0.05) and the SAM, with a false discovery rate of less than 0.02. Based on gene expression, these 15 genes can be used to classify an OSCC. A genetic analysis of functional networks and ontologies, validated by using a qRT-PCR analysis of the tissue samples, identified four genes, ADAM15, CDC7, IL12RB2 and TNFRSF8, that demonstrated excellent concordance with the microarray data. Conclusions: Our study demonstrated that four genes (ADAM15, CDC7, IL12RB2 and TNFRSF8) had potential as novel biomarkers for the diagnosis and the treatment of an OSCC