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1.
Public Health ; 227: 70-77, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38128357

ABSTRACT

OBJECTIVE: This study aimed to explore socio-economic factors and medical conditions that affect regular stomach cancer (SC) screening among Korean adults. STUDY DESIGN: This was a retrospective observational study. METHODS: Study subjects were 5545 adults aged ≥40 years who participated in the 2007-2012 Korean National Health and Nutrition Examination Survey and were followed up to year 2017 based on data linking to the Korean National Health Insurance Service and Korean Health Insurance Review and Assessment. Socio-economic factors included sex, age, residential area, education, occupation, marital status, disability, public and private health insurance, service through local public health organizations, history of cancer except for SC, and family history of SC. Medical factors included six gastric lesions with the possibility of facilitating SC screening, including benign gastric neoplasm, chronic atrophic gastritis, gastric polyp, Helicobacter pylori infection, intestinal metaplasia, and peptic ulcers. The outcome was adherence to SC screening, which was divided into non-adherence, irregular adherence, and regular adherence. RESULTS: After adjusting for the effects of socio-economic factors, multivariate ordinal logistic regression revealed that participants with a history of four types of gastric lesions were more likely to regularly participate in SC screening: chronic atrophic gastritis (odds ratio [OR] 1.567; 95% confidence interval [CI] = 1.276-1.923), gastric polyps (OR 1.565; 95% CI = 1.223-2.003), H. pylori infection (OR 1.637; 95% CI = 1.338-2.003), and peptic ulcer (OR 2.226; 95% CI 1.750-2.831). CONCLUSIONS: To improve participation in SC screening, it is necessary to implement personalized strategies for individuals at risk for gastric cancer in addition to population-based strategies for vulnerable groups.


Subject(s)
Adenomatous Polyps , Gastritis, Atrophic , Helicobacter Infections , Helicobacter pylori , Stomach Neoplasms , Adult , Humans , Stomach Neoplasms/diagnosis , Stomach Neoplasms/epidemiology , Gastritis, Atrophic/pathology , Retrospective Studies , Longitudinal Studies , Early Detection of Cancer , Helicobacter Infections/diagnosis , Helicobacter Infections/epidemiology , Helicobacter Infections/pathology , Nutrition Surveys , Public Health , Economic Factors , Republic of Korea/epidemiology , Risk Factors
2.
Article in English, Russian | MEDLINE | ID: mdl-37325828

ABSTRACT

BACKGROUND: Status epilepticus (SE) is characterized by continuous course of clinical and/or electrographic epileptic seizures. There are little data on the course and outcomes of SE after resection of brain tumors. OBJECTIVE: To analyze clinical and electrographic manifestations of SE, its course and outcomes in short-term period after resection of brain tumors. MATERIAL AND METHODS: We analyzed medical records of 18 patients over 18 years old between 2012 and 2019. All patients underwent resection of brain tumor and developed SE after surgery. Clinical criteria were repeated epileptic seizures without interictal recovery of consciousness, stereotypical motor phenomena, impaired consciousness with continued epileptic activity according to video-EEG data. We analyzed EEG data, neurological status, CT and laboratory data. RESULTS: Metastases (33%) and meningiomas (16%) prevailed. Supratentorial tumors were observed in 61% of patients. Two patients had preoperative seizures. Non-convulsive SE was diagnosed in 62% of patients. SE was successfully treated in 77% of cases. Mortality rate in patients with SE was 44%. CONCLUSION: Early postoperative SE is rare after brain tumor surgery (about 0.09%). Nevertheless, this complication is associated with high mortality. Non-convulsive SE is common (62%) that should be considered in postoperative management.


Subject(s)
Brain Neoplasms , Status Epilepticus , Humans , Adolescent , Status Epilepticus/etiology , Status Epilepticus/surgery , Status Epilepticus/diagnosis , Seizures , Electroencephalography/adverse effects , Consciousness , Brain Neoplasms/surgery , Brain Neoplasms/complications
3.
Iran J Vet Res ; 24(3): 242-246, 2023.
Article in English | MEDLINE | ID: mdl-38269008

ABSTRACT

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.

4.
Eur Rev Med Pharmacol Sci ; 26(1): 84-89, 2022 Jan.
Article in English | MEDLINE | ID: mdl-35049023

ABSTRACT

OBJECTIVE: We aimed to evaluate the reliability and validity of the adapted Korean version of the Quality-of-Life Profile for Spine Deformities (QLPSD) questionnaire. PATIENTS AND METHODS: English version of QLPSD was translated into Korean according to previously published guidelines. The Korean version of the QLPSD questionnaire and the Korean version of the SRS-22 was sent to 120 consecutive idiopathic scoliosis patients wearing braces recruited from the outpatient clinic. Reliability assessment and construct validity were evaluated. RESULTS: The intraobserver reliability of all items in the questionnaire had a kappa statistic of agreement greater than 0.6. The QLPSD showed good test/re-test reliability (ICC = 0.815). The internal consistency of Cronbach's α was found to be very good (α = 0.918). The Korean version of QLPSD showed a significant correlation with the SRS-22 total score (p<0.001, r=-0.811) and single SRS-22 domains scores. CONCLUSIONS: The adapted Korean version of the QLPSD was successfully translated and showed good measurement properties. As such, it is considered suitable for outcome assessments in Korean-speaking patients with idiopathic scoliosis.


Subject(s)
Scoliosis , Adolescent , Humans , Psychometrics , Quality of Life , Reproducibility of Results , Republic of Korea , Scoliosis/diagnosis , Surveys and Questionnaires
5.
Biotech Histochem ; 96(7): 487-497, 2021 Oct.
Article in English | MEDLINE | ID: mdl-32938242

ABSTRACT

To characterize atherogenesis functionally, we studied the functional heterogeneity of endotheliocytes in carotid vessels with atherosclerotic plaques and identified several distinct cell clusters. We measured the Ki-67 labeling index (Ki-67 LI), percentage of Bcl-2 cells (CP) and expression of CCL5, IL 6 and VCAM1 in each cell cluster. We also investigated how these indicators change when the plaque becomes unstable and how they affect the risk of adverse cerebrovascular events in patients. We evaluated the inter-cluster gradient of marker activity and its relation to patient prognosis. We identified five endothelial clusters: the under plaque cluster (UPC), peripheral cluster (PC), marginal cluster (MC), transient cluster (TC) and outside plaque cluster (OC). The UPC exhibited the greatest proliferative, proinflammatory and adhesive activity, but low anti-apoptotic activity. The PC exhibited the second greatest proliferative, adhesive and proinflammatory activity. Progression of atherosclerosis and transition of a stable atherosclerotic plaque to an unstable one was accompanied by increased expression of nearly all markers. The proliferative activity in the UPC, PC and OC, and the pro-inflammatory activity in UPC and anti-apoptotic activity in the PC, were correlated with prognosis. Also, two gradients of proliferative activity and a gradient of pro-inflammatory activity were associated with risk of adverse events.


Subject(s)
Atherosclerosis , Plaque, Atherosclerotic , Biomarkers , Endothelium , Humans , Prognosis
6.
World J Surg ; 45(3): 782-789, 2021 Mar.
Article in English | MEDLINE | ID: mdl-33263777

ABSTRACT

BACKGROUND: The United Kingdom Registry of Endocrine and Thyroid Surgeons is a national database holding details on > 28,000 parathyroidectomies. METHODS: An extract (2004-2017) of the database was analysed to investigate the reported efficacy, safety and use of intra-operative surgical adjuncts in targeted parathyroidectomy (tPTx) and bilateral neck exploration (BNE) for adult, first-time primary hyperparathyroidism (PHPT). RESULTS: 50.9% of 21,738 cases underwent tPTx. Excellent short-term (median follow-up 35 days) post-operative normocalcaemia rates were reported overall (tPTx 96.6%, BNE 94.5%, p < 0.05) and in image-positive cases (tPTx 96.7%, BNE 96%, p < 0.05). Intra-operative PTH improved overall normocalcaemia rates (tPTx 97.8% vs 96.3%, BNE 95% vs 94.4%: both p < 0.05). Intra-operative nerve monitoring reduced vocal cord (VC) dysfunction in image-positive tPTx, but not in BNE (97.8% vs 93.2%, p < 0.05). Complications were higher following BNE (7.4% vs 3.8%, p < 0.05), especially hypocalcaemia (5.3% vs 2%, p < 0.05). There was no difference in rates of subjective dysphonia following tPTx or BNE (2.4% vs 2.3%, p > 0.05), nor any difference in VC dysfunction when formally examined (4.9% vs 4.1%, p > 0.05). CONCLUSIONS: In image-positive, first time, adult PHPT cases, tPTx is as safe and effective as BNE, with both achieving excellent short-term results with minimal complications.


Subject(s)
Hyperparathyroidism, Primary , Adult , Humans , Hyperparathyroidism, Primary/surgery , Parathyroid Hormone , Parathyroidectomy , Registries , Thyroid Gland , United Kingdom/epidemiology
7.
Article in Russian | MEDLINE | ID: mdl-32759928

ABSTRACT

Combination of meningioma and glioblastoma within the same anatomical region is casuistry. We found only 13 case reports in the available literature. Some of the authors reported induced nature of the second tumor, i.e. development under the influence of the primary neoplasm. We report a patient with glioblastoma of the right frontoparietotemporal region in 3 years after previous resection of benign right-sided meningioma of sphenoid wings. Mathematical analysis of the discovered pattern resulted conclusion about its random nature, i.e. no causal relationship between both neoplasms.


Subject(s)
Glioblastoma/diagnostic imaging , Meningeal Neoplasms/surgery , Meningioma/surgery , Humans , Sphenoid Bone
8.
Sci Rep ; 10(1): 3995, 2020 Mar 04.
Article in English | MEDLINE | ID: mdl-32132624

ABSTRACT

Cuprous halides, characterized by a direct wide band-gap and a good lattice matching with Si, is an intrinsic p-type I-VII compound semiconductor. It shows remarkable optoelectronic properties, including a large exciton binding energy at room temperature and a very small piezoelectric coefficient. The major obstacle to its application is the difficulty in growing a single-crystal epitaxial film of cuprous halides. We first demonstrate the single crystal epitaxy of high quality cuprous iodide (CuI) film grown on Si and sapphire substrates by molecular beam epitaxy. Enhanced photoluminescence on the order of magnitude larger than that of GaN and continuous-wave optically pumped lasing were found in MBE grown CuI film. The intrinsic p-type characteristics of CuI were confirmed using an n-AlGaN/p-CuI junction that emits blue light. The discovery will provide an alternative way towards highly efficient optoelectronic devices compatible with both Si and III-nitride technologies.

9.
Article in Russian | MEDLINE | ID: mdl-32207743

ABSTRACT

Brain metastases of various types of cancer are diagnosed in 8-10% of all cancer patients. In the world literature, only 30 cases of cancer metastasis to the pituitary adenoma are described. This article presents yet another observation of a patient with breast cancer metastasis into the hormone-inactive pituitary adenoma at the Burdenko neurosurgical center, Russia The patient underwent endoscopic endonasal transsphenoid removal of the neoplasm. During microscopy and immunohistochemical studies of the biopsy, two types of tissue (pituitary adenoma and cancer metastasis) with different Ki-67 treated surgically (1% and over 40%) were found.


Subject(s)
Adenoma/surgery , Breast Neoplasms , Pituitary Neoplasms/surgery , Humans , Neurosurgical Procedures , Retrospective Studies , Russia
10.
Radiat Prot Dosimetry ; 187(1): 129-137, 2019 Dec 31.
Article in English | MEDLINE | ID: mdl-31506690

ABSTRACT

The purpose of the research is to develop an integrated technique for determining the effective dose (E) of external and internal exposure by different sources of ionizing radiation. The proposing technique for determining the total effective dose is based on three methods of calculation. The first one is multiplying the value of the individual dose equivalent $H_{p}(10)$ by the factor of 0.642 to account for radiation shielding by various organs and tissues and its backscattering. The second method is multiplying $H_{p}(10)$ by the conversion factor of air kerma in free air in a plate phantom, depending on the photon energy. The third method is multiplying $H_{p}(10)$ by the sum of the radiosensitivity coefficients of various organs and tissues. As a result of research, a complex method was developed for determining the total effective dose, composed of doses of cosmic radiation, external gamma-, beta- and neutron radiation, internal exposure from radionuclides, including CDP of radon and thoron, entering the body through the organs of digestion and respiration. The proposed technique for determining the total effective dose allows one to take into account the comprehensive effect of ionizing radiation sources on a person and to obtain a more accurate measure of radiation risk than the existing methods provide.


Subject(s)
Cosmic Radiation , Environmental Exposure/analysis , Gamma Rays , Phantoms, Imaging , Radiation Protection/methods , Radiation, Ionizing , Beta Particles , Humans , Radiation Dosage , Risk Assessment
11.
Int J Tuberc Lung Dis ; 23(6): 678-684, 2019 06 01.
Article in English | MEDLINE | ID: mdl-31315699

ABSTRACT

BACKGROUND Idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) share common risk factors. They could therefore be expressed in a single patient. However, the prevalence, clinical characteristics and prognosis of individuals with comorbid IPF and COPD are not known. METHOD From 2003 to 2007, the Korean Interstitial Lung Disease Study Group created a register for idiopathic interstitial pneumonia using 2002 ATS/ERS (American Thoracic Society/European Respiratory Society) criteria. Of the 1546 IPF patients assessed, 143 had decreased lung function consistent with COPD (IPF-COPD). COPD was diagnosed based on age (≥40 years) and pulmonary function (forced expiratory volume in 1 sec [FEV1]/forced vital capacity [FVC] ratio < 0.7). RESULTS The median age of the IPF-COPD group was 71.0 years (interquartile range 66.0-76.0); most patients were male (88.1%). FVC (%) was significantly higher in the IPF-COPD group; however, FEV1 (%) was significantly lower in the IPF-COPD group (P < 0.001). Diffusing capacity of the lung for carbon monoxide (DLCO) was not significantly different between the two groups. In survival analysis, age and FVC (%), but not COPD, were significantly associated with prognosis (respectively P = 0.003, 0.001 and 0.401). COPD severity was also not related to prognosis (P = 0.935). CONCLUSION The prevalence of IPF-COPD was estimated to be ∼9.2% among all IPF patients; prognosis of patients with IPF-COPD was not worse than those with IPF alone. .


Subject(s)
Idiopathic Pulmonary Fibrosis/epidemiology , Pulmonary Disease, Chronic Obstructive/epidemiology , Adult , Aged , Female , Forced Expiratory Volume , Humans , Idiopathic Pulmonary Fibrosis/complications , Idiopathic Pulmonary Fibrosis/mortality , Idiopathic Pulmonary Fibrosis/pathology , Male , Middle Aged , Pulmonary Disease, Chronic Obstructive/complications , Pulmonary Disease, Chronic Obstructive/mortality , Pulmonary Disease, Chronic Obstructive/pathology , Registries , Republic of Korea/epidemiology , Vital Capacity
12.
Oper Dent ; 44(6): 574-580, 2019.
Article in English | MEDLINE | ID: mdl-30702408

ABSTRACT

Two cases of complicated crown fracture of the maxillary incisors were restored using the fragment reattachment technique. Root canal treatment was performed, and the fractured fragment was bonded to the tooth structure using a dentin adhesive system and a flowable composite resin, followed by the insertion of a fiber post using dual-cured resin cement. Reattached fragments have shown reliable prognosis without inflammatory signs around bonded junctions after long-term follow-up.


Subject(s)
Dental Bonding , Tooth Fractures , Composite Resins , Crowns , Dental Restoration, Permanent , Follow-Up Studies , Humans , Resin Cements , Tooth Crown
13.
Transplant Proc ; 50(10): 3521-3526, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30577230

ABSTRACT

BACKGROUND: In new organ allocation policy, patients with hepatocellular carcinoma (HCC) experience a 6-month delay in being granted Model for End-Stage Liver Disease exception points. However, it may not be fair for patients at risk of early progression of HCC. METHODS: All patients who were diagnosed as United Network for Organ Sharing (UNOS) stage 1 or 2 of HCC between January 2004 and December 2012 were included. Patients who received surgical resection or liver transplant (LT) as a primary treatment and who did not receive any treatment for HCC were excluded. Patients with baseline Model for End-Stage Liver Disease score ≥22 were also excluded because they have a higher chance of receiving LT. Patients who developed extrahepatic progression within 1 year were considered as high-risk for early recurrence after LT. RESULTS: A total of 586 patients were included. Mean (SD) age was 59.9 (10.3) years and 409 patients (69.8%) were men. The cumulative incidence of estimated dropout was 8.9% at 6 months; size of the maximum nodule (≥3 cm) and nonachievement of complete response were independent factors. Extrahepatic progression developed in 16 patients (2.7%) within 1 year; size of the maximum nodule (4 cm) and alpha-fetoprotein level (>100 ng/mL) were independent predictors. CONCLUSIONS: The estimated dropout rate from the waiting list within 6 months was 8.9%. Advantage points might be needed for patients with maximum nodule size ≥3 cm or those with noncomplete response. However, in patients with maximum nodule size ≥4 cm or alpha-fetoprotein level >100 ng/mL, caution is needed.


Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Liver Transplantation , Patient Selection , Waiting Lists , Adult , Aged , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/surgery , Disease Progression , Female , Humans , Liver Neoplasms/pathology , Liver Neoplasms/surgery , Male , Middle Aged , Risk Factors , Waiting Lists/mortality
14.
Rev Sci Instrum ; 89(11): 114902, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30501312

ABSTRACT

This research work demonstrates an innovative technique to measure the thermal conductivity of a small volume of non-volatile liquids. The method utilizes a micro-pipette thermal sensor (MPTS) (tip diameter < 2 µm) and is based on laser point heating thermometry and transient heat transfer. A laser beam is irradiated at the sensor tip immersed in a few microliters of the test fluid and the transient temperature change is recorded with the sensor. This temperature change is dependent on the surrounding fluid's thermal properties, such as thermal conductivity and diffusivity. The numerical solution for transient temperature profile for a point source is obtained using the finite element method in the COMSOL software. To determine the optimizing parameters such as thermal conductivity and power absorbed at the sensor tip, the multi-parameter fitting technique is used in MATLAB, which will fit the COMSOL simulation result with the experimental data. Three liquids with known thermal conductivity were tested to verify that the technique can be used to determine the thermal conductivity with high accuracy, and in addition, the thermal conductivity of growth media and serum used for culturing cancer cells is estimated. With the sensor size of 1-2 µm, we demonstrate the possibility of using this described method as the MPTS technique for measuring the thermal properties of microfluidic samples and biological fluids.

15.
BJS Open ; 2(6): 364-370, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30511037

ABSTRACT

BACKGROUND: The majority of patients with primary hyperparathyroidism (PHPT) have a single overactive adenoma. Advances in preoperative imaging and surgical adjuncts have given rise to minimally invasive parathyroidectomy (MIP), with lower complication rates in comparison with bilateral neck exploration. Misdiagnosis and undertreatment of multiglandular disease, leading to potentially higher recurrence rates, remains a concern. This study evaluated risks of long-term (1 year or more) recurrence following 'targeted' MIP in PHPT. METHODS: Multiple databases were searched for studies published between January 2004 and March 2017, looking at long-term outcomes (1 year or more) following targeted MIP for PHPT. English-language studies, with at least 50 patients and a mean follow-up of 1 year, were included. RESULTS: A total of 5282 patients from 14 studies were included. Overall mean recurrence and cure rates were 1·6 (range 0-3·5) and 96·9 (95·5-100) per cent respectively. Mean follow-up was 33·5 (1-145) months. When intraoperative parathyroid hormone (PTH) measurements were not done, cure rates were higher (99·3 per cent versus 98·1 per cent with use of intraoperative PTH measurement; P < 0·001) and recurrence rates lower (0·2 versus 1·5 per cent respectively; P < 0·001). CONCLUSION: Targeted MIP for a presumed single overactive adenoma was associated with very low recurrence rates, without the need for intraoperative PTH measurement when preoperative imaging studies were concordant. Targeted MIP should be encouraged.

16.
Transplant Proc ; 50(4): 1147-1152, 2018 May.
Article in English | MEDLINE | ID: mdl-29731083

ABSTRACT

BACKGROUND: Liver transplantation (LT) is an established therapeutic modality for patients with end-stage liver disease. The use of marginal donors has become more common worldwide due to the sharp increase in recipients, with a consequent shortage of suitable organs. We analyzed our single-center experience over the last 8 years in LT to evaluate the outcomes of using so-called "marginal donors." METHODS: We retrospectively analyzed the database of all LTs performed at our institution from 2009 to 2017. Only patients undergoing deceased-donor LTs were analyzed. Marginal grafts were defined as livers from donors >60 years of age, livers from donors with serum sodium levels >155 mEq, graft steatosis >30%, livers with cold ischemia time ≥12 hours, livers from donors who were hepatitis B or C virus positive, livers recovered from donation after cardiac death, and livers split between 2 recipients. Patients receiving marginal grafts (marginal group) were compared with patients receiving standard grafts (standard group). RESULTS: A total of 106 patients underwent deceased-donor LT. There were 55 patients in the standard group and 51 patients in the marginal group. There were no significant differences in terms of age, sex, Model for End-Stage Liver Disease score, underlying liver disease, presence of hepatocellular carcinoma, and hospital stay between the 2 groups. Although the incidence of acute cellular rejection, cytomegalovirus infection, and postoperative complications was similar between the 2 groups, the incidence of early allograft dysfunction was higher in the marginal group. With a median follow-up of 26 months, the 1-, 3-, and 5-year overall and graft (death-censored) survivals in the marginal group were 85.5%, 75%, and 69.2% and 85.9%, 83.6%, and 77.2%, respectively. Patient overall survival and graft survival (death-censored) were significantly lower in the marginal group (P = .023 and P = .048, respectively). On multivariate analysis, receiving a marginal graft (hazard ratio [HR], 4.862 [95% confidence interval (CI), 1.233-19.171]; P = .024) and occurrence of postoperative complications (HR, 4.547 [95% CI, 1.279-16.168]; P = .019) were significantly associated with worse patient overall survival. Also, when factors associated with marginal graft were analyzed separately, graft steatosis >30% was independently associated with survival (HR, 5.947 [95% CI, 1.481-23.886]; P = .012). CONCLUSIONS: Patients receiving marginal grafts showed lower but acceptable overall survival and graft survival. However, because graft steatosis >30% was independently associated with worse survival, caution must be exercised when using this type of marginal graft by weighing the risk and benefits.


Subject(s)
Liver Transplantation/methods , Tissue Donors/supply & distribution , Transplants/pathology , Adult , Aged , Cold Ischemia , Fatty Liver , Female , Graft Rejection , Graft Survival , Humans , Liver Transplantation/adverse effects , Liver Transplantation/mortality , Male , Middle Aged , Proportional Hazards Models , Republic of Korea , Retrospective Studies , Transplantation, Homologous , Young Adult
17.
Proc Natl Acad Sci U S A ; 115(9): 1992-1997, 2018 02 27.
Article in English | MEDLINE | ID: mdl-29440490

ABSTRACT

Despite the widespread use of silicon in modern technology, its peculiar thermal expansion is not well understood. Adapting harmonic phonons to the specific volume at temperature, the quasiharmonic approximation, has become accepted for simulating the thermal expansion, but has given ambiguous interpretations for microscopic mechanisms. To test atomistic mechanisms, we performed inelastic neutron scattering experiments from 100 K to 1,500 K on a single crystal of silicon to measure the changes in phonon frequencies. Our state-of-the-art ab initio calculations, which fully account for phonon anharmonicity and nuclear quantum effects, reproduced the measured shifts of individual phonons with temperature, whereas quasiharmonic shifts were mostly of the wrong sign. Surprisingly, the accepted quasiharmonic model was found to predict the thermal expansion owing to a large cancellation of contributions from individual phonons.

19.
Eur J Neurol ; 24(10): 1290-1299, 2017 10.
Article in English | MEDLINE | ID: mdl-28833921

ABSTRACT

BACKGROUND AND PURPOSE: Brain connectivity analysis has been widely used to investigate brain plasticity and recovery-related indicators of patients with stroke. However, results remain controversial because of interindividual variability of initial impairment and subsequent recovery of function. In this study, we aimed to investigate the differences in network plasticity and motor recovery-related indicators according to initial severity. METHODS: We divided participants (16 males and 14 females, aged 54.2 ± 12.0 years) into groups of different severity by Fugl-Mayer Assessment score, i.e. moderate (50-84), severe (20-49) and extremely severe (<20) impairment groups. Longitudinal resting-state functional magnetic resonance imaging data were acquired at 2 weeks and 3 months after onset. The differences in network plasticity and recovery-related indicators between groups were investigated using network distance and graph measurements. RESULTS: As the level of impairment increased, the network balance was more disrupted. Network balance, interhemispheric connectivity and network efficiency were recovered at 3 months only in the moderate impairment group. However, this was not the case in the extremely severe impairment group. A single connection strength between the ipsilesional primary motor cortex and ventral premotor cortex was implicated in the recovery of motor function for the extremely severe impairment group. The connections of the ipsilesional primary motor cortex-ventral premotor cortex were positively associated with motor recovery as the patients were more severely impaired. CONCLUSIONS: Differences in plasticity and recovery-related indicators of motor networks were noted according to impairment severity. Our results may suggest meaningful implications for recovery prediction and treatment strategies in future stroke research.


Subject(s)
Brain/physiopathology , Motor Cortex/physiopathology , Neuronal Plasticity/physiology , Recovery of Function/physiology , Stroke/physiopathology , Adult , Aged , Brain/diagnostic imaging , Brain Mapping/methods , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Severity of Illness Index , Stroke/diagnostic imaging
20.
Tech Coloproctol ; 21(5): 345-353, 2017 May.
Article in English | MEDLINE | ID: mdl-28567691

ABSTRACT

PURPOSE: Injection of adipose tissue-derived stem cells (ASCs) is a novel method for the treatment of complex perianal fistulas. We aimed to evaluate the safety and efficacy of ASCs in the treatment of complex anal fistulas not associated with Crohn's disease. METHODS: A phase II clinical trial was performed comparing two different doses of ASCs (group 1: 1 × 107 cells/mL and group 2: 2 × 107 cells/mL). Eligible patients were administered an amount of ASCs proportional to the length of the fistula by injection into the submucosal layer surrounding the internal opening and inside of the fistula tract. ASCs at twice the initial concentration were administered if complete closure was not achieved within 8 weeks. The efficacy endpoint was the complete closure of fistulas 8 weeks after injection. Patients demonstrating complete closure at week 8 were subjected to follow-up for 6 months. RESULTS: Fifteen patients were injected with ASCs; thirteen completed the study. Complete closure was observed in 69.2% (9/13) of patients at 8 weeks. Three of five patients in group 1, and six of eight in group 2 displayed complete closure; no significant differences were observed between the groups. Six of nine patients who showed complete closure participated in additional follow-up; five (83.3%) showed persistent response at 6 months. No grade 3 or 4 adverse events (AEs) were observed; observed AEs were not related to ASC treatment. CONCLUSION: ASCs might be a good option for the treatment of complex perianal fistulas are not healed by conventional operative procedures.


Subject(s)
Adipocytes/transplantation , Adipose Tissue/cytology , Rectal Fistula/therapy , Stem Cell Transplantation/methods , Adult , Humans , Male , Middle Aged , Rectal Fistula/etiology , Treatment Outcome , Young Adult
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