Atomic-scale interpretation of the quantum oscillations in cuprate superconductors

Cuprate superconductors display unusual features in bothkspace and real space as the superconductivity is suppressed-a broken Fermi surface, charge density wave, and pseudogap. Contrarily, recent transport measurements on cuprates under high magnetic fields report quantum oscillations (QOs), which imply rather a usual Fermi liquid behavior. To settle the disagreement, we investigated Bi₂Sr₂CaCu₂O_8+δunder a magnetic field in an atomic scale. A particle-hole (p-h) asymmetrically dispersing density of states (DOSs) modulation was found at the vortices on a slightly underdoped sample, while on a highly underdoped sample, no trace of the vortex was found even at 13 T. However, a similar p-h asymmetric DOS modulation persisted in almost an entire field of view. From this observation, we infer an alternative explanation of the QO results by providing a unifying picture where the aforementioned seemingly conflicting evidence from angle-resolved photoemission spectroscopy, spectroscopic imaging scanning tunneling microscopy, and magneto-transport measurements can be understood solely in terms of the DOS modulations.

Mechanical Thrombectomy for the Treatment of Anterior Cerebral Artery Occlusion: A Systematic Review of the Literature

BACKGROUND

The overall safety and efficacy of mechanical thrombectomy for anterior cerebral artery strokes remain unclear.

PURPOSE

Our aim was to summarize procedural and clinical outcomes in patients who underwent mechanical thrombectomy for treatment of anterior cerebral artery ischemic stroke.

DATA SOURCES

A systematic literature review was performed using PubMed, Ovid MEDLINE, and the Web of Science from inception until March 4, 2022.

STUDY SELECTION

We identified 9 studies with a total of 168 patients with mechanical thrombectomy-treated anterior cerebral artery occlusions.

DATA ANALYSIS

Recanalization, procedural data, and clinical outcome at last follow-up were collected and summarized. Categoric variables were reported as proportions. The χ² test of independence or the Kruskal-Wallis test was performed to assess the relationship between selected variables and the anterior cerebral artery embolus type (ie, primary isolated anterior cerebral artery, primary combined anterior cerebral artery, and secondary anterior cerebral artery occlusion) or the mechanical thrombectomy technique.

DATA SYNTHESIS

For mechanical thrombectomy-treated anterior cerebral artery occlusions, recanalization modified TICI 2b/3 was achieved in 80%, postprocedural complications occurred in 17% of patients, and the 90-day mortality rate was 19%. The rate of symptomatic intracranial hemorrhage varied depending on the anterior cerebral artery embolus type (χ² = 8.45, P = .01).

LIMITATIONS

This analysis did not consider factors such as small-study effects that affect reliability and limit interpretation.

CONCLUSIONS

Mechanical thrombectomy for the treatment of anterior cerebral artery occlusions is safe and efficacious, offering a favorable rate of recanalization and procedural complications. Mechanical thrombectomy-treated anterior cerebral artery occlusions appear to have lower rates of short-term good functional outcomes and an increased risk of symptomatic intracerebral hemorrhage compared with mechanical thrombectomy-treated MCA/ICA occlusions. Single and multicenter studies are needed to further examine the safety and efficacy of mechanical thrombectomy-treated anterior cerebral artery occlusions.

Genetic and clinical characteristics of transthyretin cardiac amyloidosis in Koreans

Background/Introduction

Transthyretin amyloidosis with mutations (aTTRv amyloidosis) have over 100 recognized pathogenic mutations of the TTR gene and its clinical manifestations are very heterogenous. Through the global THAOS (Transthyretin Amyloidosis Outcomes Survey) patient registry, different and several types of mutants and clinical differences have been identified. Awareness of aTTRv amyloidosis is now becoming somewhat significant amongst physicians all over the world. This is a detailed look at such efforts in Korea.

Purpose

We aimed to seek the geologic significance of aTTRv amyloidosis in South Korea.

Methods

This was an analysis of 638 Korean amyloidosis patients in a single center over a period of 16 years from 1995 to October 2021. 95 individuals were found with aTTR mutations.

Results

aTTRv amyloidosis constituted 14.8% (n=95) of amyloidosis patients, and the most commonly involved organ being the heart (61.7%, n=58). Unlike the rest of the world, the mixed phenotype was most common (51.0%, n=48) in Korea and the most universal mutation in Koreans were Asp38Ala, which only constitutes about 1.0% in the THAOS registry. Val30Met mutation, which comprises 76% of the mutation in the THAOS registry, was mostly associated the neurologic phenotypes. However, the same mutations in Korea mixed phenotypes with cardiac (38.4%) and neurologic (37%) symptoms.

Conclusion

aTTRv amyloidosis in Korea is different from other patients worldwide. The mixed phenotype was most common, emphasizing the need for heart failure management in the Korean population. Genotype wise, Koreans held a less common mutation of Asp38Ala. The most common mutation of Val30Met was more likely to be associated cardiac symptoms, which concurs with other studies that suggesting that geological features are more important than mutations itself.

Funding Acknowledgement

Type of funding sources: None.

Clinical features and prognosis of patients with idiopathic pulmonary fibrosis and chronic obstructive pulmonary disease

<sec> <title>BACKGROUND</title> 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. </sec> <sec> <title>METHOD</title> 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). </sec> <sec> <title>RESULTS</title> 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 (DL_CO) 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). </sec> <sec> <title>CONCLUSION</title> 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. </sec>.

STIM1 knock-down decreases the affinity of obinutuzumab for CD20 by altering CD20 localization to Triton-soluble membrane

Obinutuzumab is thought to exert its effects through its high antibody-dependent cellular cytotoxicity (ADCC) via glyco-engineering of the Fc region. In addition, obinutuzumab causes direct binding-induced cell death (DCD) only by specifically binding to its target CD20, a Ca²⁺ channel. However, the specific features of CD20 related to obinutuzumab binding-induction of cell death are not clearly understood. In this study, we evaluated the relationship between the Ca²⁺ channel features of CD20 as a store-operated Ca²⁺ channel (SOC) and obinutuzumab binding-induced cell death. Ca²⁺ channel function and biochemical analysis revealed that CD20 is an Orai1- and stromal interaction molecule (STIM1)-dependent Ca²⁺ pore. However, binding of obinutuzumab on CD20 did not have any effect on Ca²⁺ influx activity of CD20; the direct cell death rate mediated by obinutuzumab binding was almost equivalent with or without the extracellular Ca²⁺ condition. Given the apparent interaction between STIM1 and CD20, we observed Triton-X solubilized obinutuzumab-bound CD20 accompanied by STIM1. Subsequently, obinutuzumab binding and cell death were decreased by STIM1 knock-down in Ramos B cells. Thus, STIM1 directly contributes to cell death by increasing the affinity of cells for obinutuzumab by transferring CD20 to the Triton-soluble membrane region.

Treatment of latent tuberculous infection among health care workers at a tertiary hospital in Korea

OBJECTIVE

To evaluate the acceptance of, adherence to, and outcomes of latent tuberculous infection (LTBI) treatment among health care workers (HCWs).

DESIGN

This was a retrospective study in a tertiary hospital in Korea. From May to August 2017, 2190 HCWs simultaneously underwent a tuberculin skin test (TST) and interferon-gamma release assay (IGRA). LTBI was diagnosed if the TST induration was 10 mm or IGRA results were positive.

RESULTS

Of 2190 HCWs tested, 1006 (45.9%) were diagnosed with LTBI. Of these, 655 (65.1%) HCWs visited out-patient clinics, 234 (35.7%) of whom were advised treatment by physicians. Among these, 120 (51.3%) accepted the physicians' recommendations. In general, HCWs who were older, male and smoked were less likely to visit out-patient clinics. Sixty (50%) HCWs received 3 months of isoniazid plus rifampicin (3HR) and 57 (47.5%) HCWs received 4 months of rifampicin (4R). The proportion of HCWs with 2 side effects (3HR 20% vs. 4R 7.0%, P = 0.041) and drug stoppage rate (3HR 20% vs. 4R 5.3%, P = 0.017) were higher in the 3HR group than in the 4R group. Of the 120 HCWs, 78 (65%) completed LTBI treatment.

CONCLUSION

Overall, the acceptance and completion rate for LTBI treatment was not adequate. For effective LTBI management in HCWs, further programmatic strategies are needed.

Cooper Pair Density of Bi2Sr2CaCu2O8+ x in Atomic scale at 4.2 K

In pursuit of the elusive mechanism of high- T _C superconductors (HTSC), spectroscopic imaging scanning tunneling microscopy (SI-STM) is an indispensable tool for surveying local properties of HTSC. Since a conventional STM utilizes metal tips, which allow the examination of only quasiparticles and not superconducting (SC) pairs, Josephson tunneling using STM has been demonstrated by many authors in the past. An atomically resolved scanning Josephson tunneling microscopy (SJTM), however, was realized only recently on Bi₂Sr₂CaCu₂O_{8+ x} (Bi-2212) below 50 mK and on the Pb(110) surface at 20 mK. Here we report the atomically resolved SJTM on Bi₂Sr₂CaCu₂O_{8+ x} at 4.2 K using Bi-2212 tips created in situ. The I- V characteristics show clear zero bias conductance peaks following Ambegaokar-Baratoff (AB) theory. A gap map was produced for the first time using an atomically resolved Josephson critical current map I _C( r) and AB theory. Surprisingly, we found that this new gap map is anticorrelated to the gap map produced by a conventional method relying on the coherence peaks. Quasiparticle resonance due to a single isolated zinc atom impurity was also observed by SJTM, indicating that atomically resolved SJTM was achieved at 4.2 K. Our result provides a starting point for realizing SJTM at even higher temperatures, rendering possible investigation of the existence of SC pairs in HTSC above the T _C.

Acquisition of Carbapenemase-Producing Enterobacteriaceae in Solid Organ Transplantation Recipients

BACKGROUND

Carbapenemase-producing Enterobacteriaceae (CPE) can lead to life-threatening outcomes with rapid spread of the carbapenemase gene in solid organ transplantation (SOT) recipients because of limitations of available antibiotics. We examined the characteristics and importance of CPE acquisition in SOT recipients with large numbers of CPE isolates.

METHODS

Between November 2015 and October 2016, 584 CPE isolates were found in 37 recipients and verified by carbapenemase gene multiplex polymerase chain reaction (PCR). One hundred recipients with at least 2 negative results in carbapenemase PCR for stool surveillance and no CPE isolates in clinical samples were retrospectively included.

RESULTS

Most CPE isolates were Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (546, 93.5%). The most frequent transplantation organ was lung (43.3%), and the most common sample with CPE isolates other than stool was respiratory tract (22.6%). The median time between SOT and first CPE acquisition was 7 days. All-cause mortality was significantly higher in recipients with CPE than in those without CPE (24.3% vs 10.0%; P = .03). In multivariate regression analysis, stool colonization of vancomycin-resistant Enterococci and/or Clostridium difficile during 30 days before SOT (odds ratio [OR], 3.28; 95% CI, 1.24-8.68; P = .02), lung transplantation (OR, 4.50; 95% CI, 1.19-17.03; P = .03), and intensive care unit stay ≥2 weeks (OR, 6.21; 95% CI, 1.72-22.45; P = .005) were associated with acquisition of CPE.

CONCLUSIONS

Early posttransplantation CPE acquisition may affect the clinical outcome of SOT recipients. Careful screening for CPE during the early posttransplantation period would be meaningful in recipients with risk factors.

In vitro Analysis of the Hemostatic Properties of Whole Blood Products Prepared with a Platelet-Sparing Leukoreduction Filter

Background

Warm fresh whole blood (WFWB) is an ideal resuscitation fluid for exsanguinating patients but there are myriad logistic and infectious issues associated with its use. Cold whole blood (CWB) may be an acceptable alternative to the reconstituted whole blood (RWB), the current standard of care. A leukoreduction filter has been developed which maintains platelet count while eliminating white blood cells but its effect on platelet function is unknown. We hypothesize that CWB will retain an acceptable functional coagulation profile after filtration and over time.

Study Design and Methods

WFWB and CWB samples were obtained from eight donors and four units of RWB were created. The quantitative and qualitative in vitro coagulation profiles of WFWB, RWB, and CWB over time were compared.

Results

Filtration was successful at removing white blood cells (5.5 ± 1.2 vs. 0.3 ± 0.3 × 10⁶/L) while retaining an adequate platelet count (172.0 ± 47.0 to 166.0 ± 42.3 × 10⁹/L) and hemoglobin concentration (13.7 ± 0.5 vs. 13.0 ± 0.7 g/dL). Rotational Thromboelastography (ROTEM) results revealed a similar clotting time (CT) before and after filtration (64.9 ± 5.1 vs. 64.1 ± 6.8 s) but a decreased maximum clot firmness (MCF) (58.6 ± 4.2 vs. 54.9 ± 4.6 mm). Platelet aggregation decreased substantially (28.8 ± 6.7 vs. 9.3 ± 2.1 ohm) immediately after filtration. CWB function continued to diminish over time.

Conclusion

CWB holds great promise as a surrogate for WFWB, but use of a platelet-sparing LR filter diminishes platelet function almost immediately after filtration.

Acute Basilar Artery Occlusion: Differences in Characteristics and Outcomes after Endovascular Therapy between Patients with and without Underlying Severe Atherosclerotic Stenosis

BACKGROUND AND PURPOSE

Prediction of underlying intracranial atherosclerotic stenosis before endovascular therapy might be helpful for appropriate therapeutic planning in patients with acute ischemic stroke. This study aimed to compare the characteristics and treatment outcomes in patients with acute basilar artery occlusion relative to the existence or nonexistence of underlying intracranial atherosclerotic stenosis.

MATERIALS AND METHODS

Sixty-two patients with acute basilar artery occlusion underwent multimodal endovascular therapy. All patients underwent stent-retriever thrombectomy as a first-line endovascular therapy. Patients with underlying intracranial atherosclerotic stenosis underwent additional intracranial angioplasty and stent placement. The clinical and imaging characteristics and treatment outcomes were retrospectively analyzed and compared between patients with and without intracranial atherosclerotic stenosis.

RESULTS

Underlying intracranial atherosclerotic stenosis was identified at the occlusion site in 15 patients (24.1%). Occlusion in the proximal segment of the basilar artery was more common in patients with intracranial atherosclerotic stenosis (60% versus 6.4%, P < .001), whereas occlusion in the distal segment was more common in those without it (91.5% versus 26.7%, P < .001). Bilateral thalamic infarction on a pretreatment DWI was less common in patients with intracranial atherosclerotic stenosis (0% versus 27.7%, P = .027) compared with those without it. There were no significant differences in the rates of successful revascularization, favorable outcome, symptomatic hemorrhage, and mortality between the 2 groups.

CONCLUSIONS

Underlying intracranial atherosclerotic stenosis was not uncommon in patients with acute basilar artery occlusion. The occlusion segment of the basilar artery and the presence or absence of bilateral thalamic infarction on a pretreatment DWI might be helpful for predicting underlying intracranial atherosclerotic stenosis in patients with acute basilar artery occlusion. Patients with and without underlying intracranial atherosclerotic stenosis who underwent endovascular therapy had similar outcomes.

The association between whole body sagittal balance and risk of falls among elderly patients seeking treatment for back pain

Objectives

The objective of this study was to assess the association between whole body sagittal balance and risk of falls in elderly patients who have sought treatment for back pain. Balanced spinal sagittal alignment is known to be important for the prevention of falls. However, spinal sagittal imbalance can be markedly compensated by the lower extremities, and whole body sagittal balance including the lower extremities should be assessed to evaluate actual imbalances related to falls.

Methods

Patients over 70 years old who visited an outpatient clinic for back pain treatment and underwent a standing whole-body radiograph were enrolled. Falls were prospectively assessed for 12 months using a monthly fall diary, and patients were divided into fallers and non-fallers according to the history of falls. Radiological parameters from whole-body radiographs and clinical data were compared between the two groups.

Results

A total of 144 patients (120 female patients and 24 male patients) completed a 12-month follow-up for assessing falls. A total of 31 patients (21.5%) reported at least one fall within the 12-month follow-up. In univariate logistic regression analysis, the risk of falls was significantly increased in older patients and those with more medical comorbidities, decreased lumbar lordosis, increased sagittal vertical axis, and increased horizontal distance between the C7 plumb line and the centre of the ankle (C7A). Increased C7A was significantly associated with increased risk of falls even after multivariate adjustment.

Conclusion

Whole body sagittal balance, measured by the horizontal distance between the C7 plumb line and the centre of the ankle, was significantly associated with risk of falls among elderly patients with back pain.

Cite this article: J. Kim, J. Y. Hwang, J. K. Oh, M. S. Park, S. W. Kim, H. Chang, T-H. Kim. The association between whole body sagittal balance and risk of falls among elderly patients seeking treatment for back pain. Bone Joint Res 2017;6:–344. DOI: 10.1302/2046-3758.65.BJR-2016-0271.R2.

Improved design for a low temperature scanning tunneling microscope with an in situ tip treatment stage

The Low Temperature Scanning Tunneling Microscope (LT-STM) is an extremely valuable tool not only in surface science but also in condensed matter physics. For years, numerous new ideas have been adopted to perfect LT-STM performances-Ultra-Low Vibration (ULV) laboratory and the rigid STM head design are among them. Here, we present three improvements for the design of the ULV laboratory and the LT-STM: tip treatment stage, sample cleaving stage, and vibration isolation system. The improved tip treatment stage enables us to perform field emission for the purpose of tip treatment in situ without exchanging samples, while our enhanced sample cleaving stage allows us to cleave samples at low temperature in a vacuum without optical access by a simple pressing motion. Our newly designed vibration isolation system provides efficient space usage while maintaining vibration isolation capability. These improvements enhance the quality of spectroscopic imaging experiments that can last for many days and provide increased data yield, which we expect can be indispensable elements in future LT-STM designs.

Association between recovery from Bell's palsy and body mass index

BACKGROUND

Although many factors have been found to be involved in recovery from Bell's palsy, no study has investigated the association between recovery from Bell's palsy and obesity. This study therefore evaluated the association between recovery from Bell's palsy and body mass index (BMI).

METHODS

Subjects were classified into five groups based on BMI (kg/m² ). Demographic and clinical characteristics were compared among these groups. Assessed factors included sex, age, time from paralysis to visiting a hospital, the presence of comorbidities such as diabetes mellitus and hypertension, degree of initial facial nerve paralysis by House-Brackmann (H-B) grade and neurophysiological testing, and final recovery rate.

RESULTS

Based on BMI, 37 subjects were classified as underweight, 169 as normal weight, 140 as overweight, 155 as obese and 42 as severely obese. Classification of the degree of initial facial nerve paralysis as moderate or severe, according to H-B grade and electroneurography, showed no difference in severity of initial facial paralysis among the five groups (P > 0.05). However, the final recovery rate was significantly higher in the normal weight than in the underweight or obese group (P < 0.05).

CONCLUSIONS

Obesity or underweight had no effect on the severity of initial facial paralysis, but the final recovery rate was lower in the obese and underweight groups than in the normal group.

Increased sagittal vertical axis is associated with less effective control of acute pain following vertebroplasty

OBJECTIVES

Although vertebroplasty is very effective for relieving acute pain from an osteoporotic vertebral compression fracture, not all patients who undergo vertebroplasty receive the same degree of benefit from the procedure. In order to identify the ideal candidate for vertebroplasty, pre-operative prognostic demographic or clinico-radiological factors need to be identified. The objective of this study was to identify the pre-operative prognostic factors related to the effect of vertebroplasty on acute pain control using a cohort of surgically and non-surgically managed patients.

PATIENTS AND METHODS

Patients with single-level acute osteoporotic vertebral compression fracture at thoracolumbar junction (T10 to L2) were followed. If the patients were not satisfied with acute pain reduction after a three-week conservative treatment, vertebroplasty was recommended. Pain assessment was carried out at the time of diagnosis, as well as three, four, six, and 12 weeks after the diagnosis. The effect of vertebroplasty, compared with conservative treatment, on back pain (visual analogue score, VAS) was analysed with the use of analysis-of-covariance models that adjusted for pre-operative VAS scores.

RESULTS

A total of 342 patients finished the 12-week follow-up, and 120 patients underwent vertebroplasty (35.1%). The effect of vertebroplasty over conservative treatment was significant regardless of age, body mass index, medical comorbidity, previous fracture, pain duration, bone mineral density, degree of vertebral body compression, and canal encroachment. However, the effect of vertebroplasty was not significant at all time points in patients with increased sagittal vertical axis.

CONCLUSIONS

For single-level acute osteoporotic vertebral compression fractures, the effect of vertebroplasty was less favourable in patients with increased sagittal vertical axis (> 5 cm) possible due to aggravation of kyphotic stress from walking imbalance.Cite this article: Y-C. Kim, D. H. Bok, H-G. Chang, S. W. Kim, M. S. Park, J. K. Oh, J. Kim, T-H. Kim. Increased sagittal vertical axis is associated with less effective control of acute pain following vertebroplasty. Bone Joint Res 2016;5:544-551. DOI: 10.1302/2046-3758.511.BJR-2016-0135.R1.

Evaluation of 2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography in rat models with hepatocellular carcinoma with liver cirrhosis

Liver cirrhosis is a predominant risk factor for hepatocellular carcinoma (HCC). However, the exact mechanism of the progression from cirrhosis to cancer remains unclear. The uptake of 2-[(18)F]-fluoro-2-deoxy-D-glucose ((18)F-FDG) is widely used as a marker of increased glucose metabolism to monitor the progression of cancer with positron emission tomography (PET)/computed tomography (CT). Here we investigated the feasibility of using (18)F-FDG PET/CT in the diethylnitrosamine (DEN) mediated experimental hepatocellular carcinoma model. Rats received weekly intraperitoneal injections of DEN for 16 weeks for induction of HCC. We recorded starting from 0 days or 0 weeks after the last DEN injection. The weight and survival rate of rats were then measured. Also, an (18)F-FDG PET scan and serum analysis were performed at minus 2, 0, plus 2, and plus 4 weeks after the last DEN injection. The body weight of rats was maintained between 350 g and 370 g during 14 and 20 weeks, and the rats were euthanized at 35 days after the last DEN injection. The serum levels of alanine transaminase (ALT), aspartate transaminase (AST), and alkaline phosphate (ALP) were significantly higher at zero weeks after the last DEN injection. The (18)F-FDG uptake for the quantitative evaluation of HCC was done by measuring the region of interest (ROI). At minus two weeks after the last DEN injection, the ROI of rats had significantly increased compared to the normal group, in a time-dependent manner. These results suggest that FDG uptake serves as a good screening test to evaluate the feasibility of DEN-induced HCC.

The effect of fibroblast growth factor on distinct differentiation potential of cord blood-derived unrestricted somatic stem cells and Wharton's jelly-derived mesenchymal stem/stromal cells

BACKGROUND AIMS

Perinatal tissues are considered an attractive source of mesenchymal stem/stromal cells (MSCs) and have unique characteristics depending on their origin. In this study, we compared the basic characteristics of unrestricted somatic stem cells isolated from cord blood (CB-USSCs) and MSCs isolated from Wharton's jelly of umbilical cords (WJ-MSCs). We also evaluated the effect of basic fibroblast growth factor (bFGF) supplementation on the growth and differentiation of these cells.

METHODS

CB-USSCs and WJ-MSCs were isolated from the same individual (n = 6), and their morphology, cell surface antigens, proliferation, expression of stemness markers and adipogenic, osteogenic and chondrogenic differentiation potentials were evaluated. Their morphology, proliferation and differentiation potentials were then also compared in the presence of bFGF supplementation (10 ng/mL).

RESULTS

Overall, CB-USSCs expressed DLK-1 and negative for all the HOX gene markers. The expression of cell surface antigen CD90, growth capacity and adipogenic differential potential of CB-USSCs were lower than those of WJ-MSCs. WJ-MSCs showed higher growth capacity, but the expression of CD73 and CD105 and their osteogenic differentiation potential were lower than those of CB-USSCs. The spindle morphology of both CB-USSCs and WJ-MSCs and the growth and adipogenic differentiation of CB-USSCs were improved by bFGF supplementation. However, the bFGF supplement did not have any positive effect on the tri-lineage differentiation potentials of WJ-MSCs.

CONCLUSIONS

CB-USSCs and WJ-MSCs each had distinct characteristics including different growth capacity, distinguishable cell surface markers and distinct adipogenic and osteogenic potentials. bFGF supplementation improved the growth capacity and adipogenic differentiation of CB-USSCs.

Associations of Low Muscle Mass and the Metabolic Syndrome in Caucasian and Asian Middle-aged and Older Adults

OBJECTIVE

Age-related declines in skeletal muscle mass may confer significant metabolic consequences for older adults. Associations of low muscle mass and metabolic syndrome (MetS) in Caucasians, and comparisons with associations observed in Asian populations, have not been reported. We examined associations of low muscle mass and metabolic syndrome (MetS) in Asian and Caucasian middle-aged and older men and women using criteria for low muscle mass.

DESIGN, SETTING AND PARTICIPANTS

Two population-based studies of Australian (Tasmanian Older Adult Cohort Study; TASOAC; N=1005) and Korean (Korean Sarcopenic Obesity Study; KSOS; N=376) community-dwelling adults, mean age 62 and 58 years, respectively.

MEASUREMENTS

Appendicular lean mass (aLM) determined by dual-energy X-ray absorptiometry and normalised to height squared (aLM/Ht2), weight (aLM/Wt) or body mass index (aLM/BMI). Participants in the lowest sex-specific 20% for aLM measures were defined as having low muscle mass. MetS was defined according to National Cholesterol Education Program Adult Treatment Panel III criteria.

RESULTS

Although Australians demonstrated generally unfavourable anthropometric and metabolic characteristics compared to Koreans, prevalence of MetS was similar (29.5% in Australians and 31.4% in Koreans, respectively). Low aLM/Ht2 was associated with significantly reduced likelihood of MetS in both Australians (OR: 0.30, 95% CI 0.19 - 0.46) and Koreans (OR: 0.31, 95% CI 0.16 - 0.62). Conversely, low aLM/BMI was associated with increased odds for MetS in Australians (OR: 1.78, 95% CI 1.12 - 2.84), but not Koreans (OR: 1.33, 95% CI = 0.67 - 2.64).

CONCLUSION

Low aLM/BMI is associated with significantly increased likelihood of MetS in Australian adults, but not Koreans, suggesting potential differences in effects of low muscle mass relative to body mass on cardiometabolic health in Caucasian and Asian middle-aged and older adults. Low muscle mass relative to height is associated with reduced likelihood of MetS in both populations.

Measurements of surgeons' exposure to ionizing radiation dose: comparison of conventional and mini C-arm fluoroscopy

This study was performed to measure the equivalent scattered radiation dose delivered to susceptible organs while simulating orthopaedic surgery using conventional and mini C-arm fluoroscopy. In addition, shielding effects on the thyroid, thymus, and gonad, and the direct exposure delivered to the patient's hands were also compared. A conventional and mini C-arms were installed in an operating room, and a hand and an operator phantom were used to simulate a patient's hand and a surgeon. Photoluminescence dosimeters were used to measure the equivalent dose by scattered radiation arriving at the thyroid, thymus, and gonad on a whole-body phantom in the position of the surgeon. Equivalent scattered radiation doses were measured in four groups: (1) unshielded conventional C-arm group; (2) unshielded mini C-arm group; (3) lead-shielded conventional C-arm group; and (4) lead-shielded mini C-arm group. Equivalent scattered radiation doses to the unshielded group were significantly lower in the mini C-arm group than those in the conventional C-arm group for all organs. The gonad in the lead-shielded conventional C-arm group showed the highest equivalent dose among operator-susceptible organs, and radiation dose was reduced by approximately 96% compared with that in the unshielded group. Scattered radiation was not detected in any susceptible organ in the lead-shielded mini C-arm group. The direct radiation dose to the hand phantom measured from the mini C-arm was significantly lower than that measured from the conventional C-arm. The results show that the equivalent scattered radiation dose to the surgeon's susceptible organs and the direct radiation dose to a patient's hand can be decreased significantly by using a mini C-arm rather than a conventional C-arm. However, protective lead garments, such as a thyroid shield and apron, should be applied to minimize radiation exposure to susceptible organs, even during use of mini C-arm fluoroscopy.

Comparison of steroid administration methods in patients with idiopathic sudden sensorineural hearing loss: a retrospective observational study

OBJECTIVES

To compare the recovery rates of patients with idiopathic sudden sensorineural hearing loss (ISSHL) treated with oral systemic steroids (PO) or intratympanic steroid injection (IT) or both.

DESIGN

A retrospective observational study.

SETTING

Tertiary referral centre.

PARTICIPANTS

Eight hundred and forty-four patients diagnosed with ISSHL within 14 days of the onset of symptoms. The patients were divided into three groups by treatment modality.

MAIN OUTCOME MEASURES

Threshold of pure-tone tests, age, accompanying symptoms and underlying diseases were compared. The level of final hearing recovery was evaluated by the application of the results of the pure-tone test that was performed at least 3 months after the completion of each treatment.

RESULTS

Final hearing recovery rate differed significantly by the type of treatment (P = 0.031). Recovery rates in the PO and combined groups were significantly higher in patients with mild (85.1% and 88.6%, respectively) than with profound (52.8% and 69.0%, respectively) hearing loss (P < 0.05). In contrast, severity and recovery rate were not significantly correlated in the IT group (P > 0.05). Combined treatment yielded significantly higher recovery rates than other treatment modalities in patients without hypertension (HTN) and diabetes mellitus (DM) (P = 0.021).

CONCLUSION

In the group treated with combined therapy, better hearing improvement was obtained than in the groups treated with systemic steroid only or with intratympanic steroid injection only without complications. These findings suggest that the combination of systemic administration and intratympanic injection may improve patient prognosis.

Outcomes Are Not Different between Patients with Intermediate and High DWI-ASPECTS after Stent-Retriever Embolectomy for Acute Anterior Circulation Stroke

BACKGROUND AND PURPOSE

Questions remain as to what benefits embolectomy provides to patients presented with considerable early ischemic changes on baseline imaging studies. This study aimed to investigate the impact of the Alberta Stroke Program Early CT Score applied to DWI on treatment outcomes in patients with acute stroke undergoing stent-retriever embolectomy.

MATERIALS AND METHODS

We retrospectively analyzed the clinical and DWI data from 171 patients with acute anterior circulation stroke who were treated with stent-retriever embolectomy within 6 hours of symptom onset. DWI-ASPECTS scores were analyzed with the full scale or were dichotomized (4-6 versus 7-10). Patients with DWI-ASPECTS ≤3 were excluded from the study. Associations between outcome and clinical and radiologic factors were determined with a multivariate logistic regression analysis. A good outcome was defined as a modified Rankin Scale score of 0-2 at 3 months.

RESULTS

The median DWI-ASPECTS was 7 (interquartile range, 6-8). The rates of good outcome, symptomatic hemorrhage, and mortality were not different between high DWI-ASPECTS (scores of 7-10) and intermediate DWI-ASPECTS (scores of 4-6) groups. In patients with an intermediate DWI-ASPECTS, good outcome was achieved in 46.5% (20/43) of patients with successful revascularization, whereas no patients without successful revascularization had a good outcome (P = .016). In multivariate logistic regression analysis, independent predictors of good outcome were age and successful revascularization.

CONCLUSIONS

Our study suggested that there were no differences in outcomes between patients with a high DWI-ASPECTS and those with an intermediate DWI-ASPECTS who underwent stent-retriever embolectomy for acute anterior circulation stroke. Thus, patients with an intermediate DWI-ASPECTS otherwise eligible for endovascular therapy may not be excluded from stent-retriever embolectomy or stroke trials.

Pipeline Embolization Device with or without Adjunctive Coil Embolization: Analysis of Complications from the IntrePED Registry

Flow diversion to treat cerebral aneurysms has revolutionized neurointerventional surgery. Because the addition of coils potentially increases the time and complexity of endovascular procedures, we sought to determine whether adjunctive coil use is associated with an increase in complications. Patients in the International Retrospective Study of Pipeline Embolization Device registry were divided into those treated with the Pipeline Embolization Device alone (n = 689 patients; n = 797 aneurysms; mean aneurysm size, 10.3 ± 7.6 mm) versus those treated with the Pipeline Embolization Device and concurrent coil embolization (n = 104 patients; n = 109 aneurysms; mean aneurysm size, 13.6 ± 7.8 mm). Patient demographics and aneurysm characteristics were examined. Rates of neurologic morbidity and mortality were compared between groups. The Pipeline Embolization Device with versus without coiling required a significantly longer procedure time (135.8 ± 63.9 versus 96.7 ± 46.2 min; P < .0001) and resulted in higher neurological morbidity (12.5% versus 7.8%; P = .13). These data suggest that either strategy represents an acceptable risk profile in the treatment of complex cerebral aneurysms and warrants further investigation.

Posterior Inferior Cerebellar Artery Patency after Flow-Diverting Stent Treatment

BACKGROUND AND PURPOSE

The rate of PICA occlusion after flow-diverting stent placement for vertebral and vertebrobasilar artery aneurysms is not known. The purpose of this study is to determine the medium-term rate of PICA patency and risk factors for occlusion after such aneurysm treatment.

MATERIALS AND METHODS

Patients were identified who had vertebral or vertebrobasilar artery aneurysms and who were treated by placing a flow-diverting stent across the PICA ostium. Demographic and procedural factors associated with stent placement were recorded. Patency of the PICA was evaluated immediately after stent placement and on follow-up angiography.

RESULTS

Thirteen patients with vertebral or vertebrobasilar artery aneurysms were treated in the study period, of whom 4 presented with subarachnoid hemorrhage. The average number of devices that spanned the PICA ostium was 1.77 (range, 1-3), with no immediate PICA occlusions. There were no postoperative strokes in the treated PICA territory, although there was 1 contralateral PICA-territory stroke of unclear etiology without clinical sequelae. In 11 patients with follow-up angiography at a mean of 10.6 months (range, 0.67-27.9 months), the PICA patency rate remained 100%.

CONCLUSIONS

Flow-diverting stent placement across the PICA ostium in the treatment of vertebral and vertebrobasilar artery aneurysms may not result in immediate or midterm PICA occlusion.

Histologic Analysis of Retrieved Clots in Acute Ischemic Stroke: Correlation with Stroke Etiology and Gradient-Echo MRI

BACKGROUND AND PURPOSE

It is unclear whether clot composition analysis is helpful to predict a stroke mechanism in acute large vessel occlusion. In addition, the relationship between early vessel signs on imaging studies and clot compositions has been poorly understood. The purpose of this study was to elucidate the relationship between clot composition and stroke etiology following mechanical thrombectomy and to investigate the effect of varied clot compositions on gradient-echo MR imaging of clots.

MATERIALS AND METHODS

Histopathologic analysis of retrieved clots from 37 patients with acute MCA occlusion was performed. Patients underwent gradient-echo imaging before endovascular therapy. Retrieved clots underwent semiquantitative proportion analysis to quantify red blood cells, fibrin, platelets, and white blood cells by area. Correlations between clot compositions and stroke subtypes and susceptibility vessel signs on gradient-echo imaging were assessed.

RESULTS

Stroke etiology was classified as cardioembolism in 22 patients (59.4%), large-artery atherosclerosis in 8 (21.6%), and undetermined in 7 (18.9%). The clots from cardioembolism had a significantly higher proportion of red blood cells (37.8% versus 16.9%, P = .031) and a lower proportion of fibrin (32.3% versus 48.5%, P = .044) compared with those from large-artery atherosclerosis. The proportion of red blood cells was significantly higher in clots with a susceptibility vessel sign than in those without it (48.0% versus 1.9%, P < .001), whereas the proportions of fibrin (26.4% versus 57.0%, P < .001) and platelets (22.6% versus 36.9%, P = .011) were significantly higher in clots without a susceptibility vessel sign than those with it.

CONCLUSIONS

The histologic composition of clots retrieved from cerebral arteries in patients with acute stroke differs between those with cardioembolism and large-artery atherosclerosis. In addition, a susceptibility vessel sign on gradient-echo imaging is strongly associated with a high proportion of red blood cells and a low proportion of fibrin and platelets in retrieved clots.

The cortical contrast accumulation from brain computed tomography after endovascular treatment predicts symptomatic hemorrhage

BACKGROUND AND PURPOSE

The prognostic value of contrast accumulation from non-contrast brain computed tomography taken immediately after endovascular reperfusion treatment in acute ischaemic stroke patients to predict symptomatic hemorrhage was studied.

METHODS

Between July 2007 and August 2014, acute anterior circulation ischaemic stroke patients who were treated by intra-arterial thrombolysis or thrombectomy were included. Contrast accumulation was defined as a high attenuation area from non-contrast brain computed tomography immediately taken after endovascular reperfusion treatment, and patients were categorized into three groups according to the presence and location of contrast: (i) negative, (ii) cortical involvement and (iii) non-cortical involvement. The rates of symptomatic hemorrhage after 24 h and functional outcome at discharge were compared between patients with and without cortical involvement.

RESULTS

Of 64 patients who were treated by endovascular intervention, contrast accumulation was detected in 56, including 33 patients with cortical involvement and 23 patients without cortical involvement. The cortical involvement pattern was more frequently associated with symptomatic hemorrhage (13 vs. 1 patient, P = 0.003) and with grave outcome at discharge with modified Rankin Scale 5 or 6 (14 vs. 4, P = 0.048) than the non-cortical involvement group. Multivariate logistic regression analysis including initial collateral status and occlusion site disclosed that cortical involvement pattern independently predicted symptomatic hemorrhage after endovascular treatment (odds ratio 19.0, confidence interval 1.6-227.6, P = 0.020).

CONCLUSION

Our study provides evidence that the cortical involvement of contrast accumulation is associated with symptomatic hemorrhage after endovascular reperfusion treatment.

Enhanced Healing of Rat Calvarial Bone Defects with Hypoxic Conditioned Medium from Mesenchymal Stem Cells through Increased Endogenous Stem Cell Migration via Regulation of ICAM-1 Targeted-microRNA-221

The use of conditioned medium from mesenchymal stem cells may be a feasible approach for regeneration of bone defects through secretion of various components of mesenchymal stem cells such as cytokines, chemokines, and growth factors. Mesenchymal stem cells secrete and accumulate multiple factors in conditioned medium under specific physiological conditions. In this study, we investigated whether the conditioned medium collected under hypoxic condition could effectively influence bone regeneration through enhanced migration and adhesion of endogenous mesenchymal stem cells. Cell migration and adhesion abilities were increased through overexpression of intercellular adhesion molecule-1 in hypoxic conditioned medium treated group. Intercellular adhesion molecule-1 was upregulated by microRNA-221 in mesenchymal stem cells because microRNAs are key regulators of various biological functions via gene expression. To investigate the effects in vivo, evaluation of bone regeneration by computed tomography and histological assays revealed that osteogenesis was enhanced in the hypoxic conditioned medium group relative to the other groups. These results suggest that behavioral changes of endogenous mesenchymal stem cells through microRNA-221 targeted-intercellular adhesion molecule-1 expression under hypoxic conditions may be a potential treatment for patients with bone defects.

Steroid plus antiviral treatment for Bell's palsy

OBJECTIVES

The effectiveness of antiviral agents for the treatment of Bell's palsy is uncertain. We evaluated whether a steroid with an antiviral agent (S + A group) provided better recovery outcomes than a steroid alone (S group) in patients with Bell's palsy.

SUBJECTS AND DESIGN

A total of 1342 patients diagnosed with Bell's palsy who visited the Kyung Hee Medical Center in Seoul, Korea, from 2002 to 2012 were included in this study. Patients in the S + A group were treated with prednisolone and antiviral agents (n = 569) and those in the S group with prednisolone alone (n = 773). Outcomes were measured using the House-Brackmann (HB) scale according to age, initial disease severity, electroneurography (ENoG) findings and underlying comorbidities.

RESULTS

The rate of recovery (HB grades I and II) with initially severe Bell's palsy (HB grades V and VI) was higher in the S + A than in the S group (P = 0.001). However, the rates of recovery were similar with initially moderate palsy (HB grades II-IV) (P = 0.502). In patients classified according to age and ENoG-determined severity of palsy, the overall recovery rate was higher in the S + A than in the S group, but the differences were not statistically significant (P > 0.05 for both). The recovery rate without diabetes mellitus (DM) and hypertension (HTN) was higher in the S + A group than in the S group (P = 0.031). But in the patients with HTN and DM, the difference in recovery rates between the S + A and S groups was not statistically significant (P = 0.805).

CONCLUSIONS

Treatment with a steroid plus antiviral agent resulted in significantly higher recovery rates than steroid therapy alone in patients with initially severe Bell's palsy and without either HTN or DM, and a nonsignificant trend towards higher recovery rates in all patients with Bell's palsy in this study. Antiviral agents may therefore help in the treatment of Bell's palsy.

Supplemented dialysis: amino acid-based solutions in peritoneal dialysis

Peritoneal dialysis is associated with several metabolic and nutritional abnormalities, some of which are related to the use of glucose-based solutions. Furthermore, the catabolic effects of uremia per se, protein and amino acid losses into the dialysate, peritonitis and poor appetite contribute to amino acid abnormalities, negative nitrogen balance and a high prevalence of malnutrition in peritoneal dialysis patients. To overcome these problems the use of amino acid instead of glucose as an osmotic agent has been proposed. Short-term studies have shown that amino acid-based solutions in peritoneal dialysis may supplement in excess the daily losses of amino acids during dialysis with glucose-based solutions. The amino acid solutions produce similar ultrafiltration and solute transport as the standard glucose solutions although the period of effective ultrafiltration is rather short. However, it should be noted that some studies have reported that the transport of small and large solutes may increase in patients using amino acid solutions. During the early 1980s several investigators have developed and tested different amino acid solutions for peritoneal dialysis. The initial clinical experience from Toronto with amino acid solutions containing large amounts of non-essential amino acids and inadequate amount of buffer were in general discouraging. The patients, who were not always malnourished and tended to have a low energy intake, developed increased BUN levels, acidosis, no improvement in nutritional status or amino acid abnormalities and, in some cases, anorexia. In 1985 a new 1% amino acid solution, containing an increased buffer amount and amino acids (mainly essential) in proportions which take the amino acid abnormalities in uremic patients into account, became available. The use of this solution resulted in some improvement in amino acid pattern and nutritional parameters, but acidosis and increased BUN levels remained problems. The experiences from these and previous studies showed that: (1) the improvement of the composition of amino acid solutions was beneficial; (2) a further increase of the buffer amount was needed; (3) patients included should have signs of protein malnutrition combined with low dietary protein intake to benefit from intraperitoneal amino acid supply, and (4) energy intake should be sufficient to prevent amino acids to end up as energy source. For this purpose a new improved 1.1% amino acid solution has been developed containing a further increase of some essential amino acids and an increased amount of lactate (40 mmol/l). This solution has been tested in malnourished patients eating 0.8 g protein/kg/day and 25-30 kcal/kg/day.(ABSTRACT TRUNCATED AT 400 WORDS)

Focused low-intensity pulsed ultrasound enhances bone regeneration in rat calvarial bone defect through enhancement of cell proliferation

A number of studies have reported the therapeutic potential of low-intensity pulsed ultrasound (LIPUS) for induction of bone repair. This study investigated whether bone regeneration might be enhanced by application of focused LIPUS to selectively stimulate fractured calvarial bone. To accomplish this, bone defects were surgically created in the middle of the skull of rats that were subsequently exposed to focused LIPUS. Bone regeneration was assessed by repeated computed tomography imaging after the operation, as well as histologic analysis with calcein, hematoxylin and eosin and proliferating cell nuclear antigen assay. At 6 wk after surgery, bone formation in the focused LIPUS-treated group improved significantly relative to the control. Interestingly, new bone tissue sprouted from focused LIPUS target points. Histologic analysis after exposure to focused LIPUS revealed that proliferating cells were significantly increased relative to the control. Taken together, these results suggest that focused LIPUS can improve re-ossification through enhancement of cell proliferation in calvarial defect sites.

Negative Susceptibility Vessel Sign and Underlying Intracranial Atherosclerotic Stenosis in Acute Middle Cerebral Artery Occlusion

BACKGROUND AND PURPOSE

The role of MR imaging in predicting underlying intracranial atherosclerotic stenosis before endovascular stroke therapy has not been studied. Our aim was to determine the diagnostic value of the negative susceptibility vessel sign on T2*-weighted gradient-echo MR imaging for predicting underlying intracranial atherosclerotic stenosis in patients with acute MCA occlusion.

MATERIALS AND METHODS

Ninety-one consecutive patients with acute stroke because of MCA occlusion underwent gradient-echo MR imaging and MRA before endovascular therapy. The negative susceptibility vessel sign was defined as an absence of a hypointense signal change within the occluded MCA on gradient-echo imaging. Underlying intracranial atherosclerotic stenosis was determined by conventional angiography. The sensitivity, specificity, predictive values, and accuracy of the negative susceptibility vessel sign for predicting the presence of underlying intracranial atherosclerotic stenosis were assessed.

RESULTS

The negative susceptibility vessel sign was identified in 42 (46.1%) of 91 patients, and 18 (19.8%) patients had an underlying intracranial atherosclerotic stenosis responsible for acute ischemic symptoms. The negative susceptibility vessel sign was more frequently observed in patients with intracranial atherosclerotic stenosis than in those without it (100% versus 32.9%, P < .001). In the prediction of an underlying intracranial atherosclerotic stenosis, the negative susceptibility vessel sign had 100% sensitivity, 67.1% specificity, 42.9% positive predictive value, 100% negative predictive value, and an accuracy of 73.6%.

CONCLUSIONS

The negative susceptibility vessel sign on gradient-echo MR imaging is a sensitive marker with a high negative predictive value for the presence of an underlying intracranial atherosclerotic stenosis in patients with acute ischemic stroke because of MCA occlusions. The susceptibility vessel sign can be used in decision-making when performing subsequent endovascular revascularization therapy in patients with acute MCA occlusions.

Changes of knee joint and ankle joint orientations after high tibial osteotomy

OBJECTIVE

We sought to determine (1) whether change in the tibial plateau inclination (TPI) after high tibial osteotomy (HTO) is different from change in the knee joint line orientation (KJLO) relative to the ground; (2) whether, in varus knee OA patients before and after HTO, these radiographic measures are different from those in normal control; and (3) whether the postoperative values of the TPI and KJLO relative to the ground are associated with short term clinical outcome scores after HTO.

DESIGN

Fifty patients who underwent HTO and 75 normal controls were assessed with four radiographic measures. We compared the measures before HTO with those after HTO and with those of the normal controls, then examined associations between the postoperative radiographic measures and clinical outcome scores 1-year after HTO.

RESULTS

After HTO, TPI increased 9.0°, whereas KJLO relative to the ground only increased 4.1°, with a compensatory change of the ankle joint line orientation. However, the postoperative KJLO relative to the ground in the HTO group was significantly different from that of the normal controls (mean difference, 4.9°; P < 0.001). In the multiple regression analyses, the postoperative radiographic measures were not associated with outcome clinical scores 1 year after HTO.

CONCLUSION

After HTO the relative KJLO changed significantly less than did the anatomical geometry of the proximal tibia. Although the KJLO after the HTO was still significantly different from that of normal knees, its value did not adversely affect clinical outcome scores 1 year after HTO.

Association between vitamin D deficiency and tuberculosis in a Korean population

BACKGROUND

Several in vitro studies have been conducted regarding the immunomodulatory and mycobactericidal roles of vitamin D in tuberculous infection. However, discrepancies exist among epidemiological studies. We compared vitamin D deficiency between patients with tuberculosis (TB) and healthy control subjects and identified risk factors for vitamin D deficiency.

METHOD

This was an age- and sex-matched case-control analysis of 94 TB cohort and 282 Korean national survey participants.

RESULTS

The median baseline 25-hydroxyvitamin D (25[OH]D) level in the TB group (9.86 ng/ml, IQR 7.19-14.15) was lower than in controls (16.03 ng/ml, IQR 12.38-20.30, P < 0.001). The prevalence of severe vitamin D deficiency was higher in patients with TB (51.1%) than in controls (8.2%, P = 0.001). The median 25(OH)D level increased from 11.40 ng/ml (IQR 7.85-15.73) to 13.18 ng/ml (IQR 10.60-19.71) after treatment completion (P = 0.037). On multivariate analysis, presence of TB and history of TB were independently associated with severe vitamin D deficiency.

CONCLUSION

Patients with TB had a higher prevalence of vitamin D deficiency than control subjects in a Korean population. The median 25(OH)D level increased after TB treatment. Further studies are needed to establish a causal relationship.

Effect of dietary antimicrobials on immune status in broiler chickens

This study evaluated the effects of dietary anticoccidial drugs plus antibiotic growth promoters (AGPs) on parameters of immunity in commercial broiler chickens. Day-old chicks were raised on used litter from a farm with endemic gangrenous dermatitis to simulate natural pathogen exposure and provided with diets containing decoquinate (DECX) or monensin (COBN) as anticoccidials plus bacitracin methylene disalicylate and roxarsone as AGPs. As a negative control, the chickens were fed with a non-supplemented diet. Immune parameters examined were concanavalin A (ConA)-stimulated spleen cell proliferation, intestine intraepithelial lymphocyte (IEL) and spleen cell subpopulations, and cytokine/chemokine mRNA levels in IELs and spleen cells. ConA-induced proliferation was decreased at 14 d post-hatch in DECX-treated chickens, and increased at 25 and 43 d in COBN-treated animals, compared with untreated controls. In DECX-treated birds, increased percentages of MHC2(+) and CD4(+) IELS were detected at 14 d, but decreased percentages of these cells were seen at 43 d, compared with untreated controls, while increased TCR2(+) IELs were evident at the latter time. Dietary COBN was associated with decreased fractions of MHC2(+) and CD4(+) IELs and reduced percentages of MHC2(+), BU1(+), and TCR1(+) spleen cells compared with controls. The levels of transcripts for interleukin-4 (IL-4), IL-6, IL-17F, IL-13, CXCLi2, interferon-γ (IFN-γ), and transforming growth factorβ4 were elevated in IELs, and those for IL-13, IL-17D, CXCLi2, and IFN-γ were increased in spleen cells, of DECX- and/or COBN-treated chickens compared with untreated controls. By contrast, IL-2 and IL-12 mRNAs in IELs, and IL-4, IL-12, and IL-17F transcripts in spleen cells, were decreased in DECX- and/or COBN-treated chickens compared with controls. These results suggest that DECX or COBN, in combination with bacitracin and roxarsone, modulate the development of the chicken post-hatch immune system.

Activation of HIF-1α (hypoxia inducible factor-1α) prevents dry eye-induced acinar cell death in the lacrimal gland

The pathogenesis of immune-mediated lacrimal gland (LG) dysfunction in Sjögren's syndrome has been thoroughly studied. However, the majority of dry eye (DE) is not related to Sjögren type, and its pathophysiology remains unclear. The purpose of this study was to determine and investigate the protective mechanisms against DE stress in mice. DE induced prominent blood vessel loss without apoptosis or necrosis in the LG. Autophagic vacuoles, distressed mitochondria, and stressed endoplasmic reticulum were observed via electron microscopy. Immunoblotting confirmed the increase in autophagic markers. Glycolytic activities were enhanced with increasing levels of succinate and malate that, in turn, activated hypoxia-inducible factor (HIF)-1α. Interestingly, the areas of stable HIF-1α expression overlapped with COX-2 and MMP-9 upregulation in LGs of DE-induced mice. We generated HIF-1α conditional knockout (CKO) mice in which HIF-1α expression was lost in the LG. Surprisingly, normal LG polarities and morphologies were completely lost with DE induction, and tremendous acinar cell apoptosis was observed. Similar to Sjögren's syndrome, CD3⁺ and CD11b⁺ cells infiltrated HIF-1α CKO LGs. Our results show that DE induced the expression of HIF-1α that activated autophagy signals to prevent further acinar cell damage and to maintain normal LG function.

Acute basilar artery occlusion: outcome of mechanical thrombectomy with Solitaire stent within 8 hours of stroke onset

BACKGROUND AND PURPOSE

Mechanical thrombectomy with a stent retriever applied shortly after symptom onset could increase good functional outcomes and improve survival in patients with acute basilar artery occlusion, but this has not yet been studied. This study evaluated the efficacy and safety of mechanical thrombectomy with a Solitaire stent within 8 hours of stroke onset in patients with acute basilar artery occlusion.

MATERIALS AND METHODS

We analyzed 25 consecutive patients with acute basilar artery occlusion who were treated with mechanical thrombectomy by use of the Solitaire stent within 8 hours of stroke symptom onset. Successful recanalization was defined as TICI grade 2b or 3. Good outcome was defined as mRS score of 0-2 at 3 months. Clinical and radiologic data in patients with good outcomes were compared with those with poor outcomes.

RESULTS

Successful recanalization was achieved in 96% (24/25) of patients, and 48% (12/25) of patients had good outcomes. Eighty-eight percent (22/25) of patients survived to 3 months. The median NIHSS score on admission was significantly lower in patients with good outcomes than in those with poor outcomes (9.5 versus 14, P = .005). Procedure-related complications occurred in 2 patients (8%). No symptomatic intracerebral hemorrhages occurred.

CONCLUSIONS

The current study suggests that mechanical thrombectomy by use of a Solitaire stent within 8 hours of stroke onset increases good outcomes and improves survival in patients with acute basilar artery occlusion.

Ankle fractures have features of an osteoporotic fracture

We report the bone attenuation of ankle joint measured on computed tomography (CT) and the cause of injury in patients with ankle fractures. The results showed age- and gender-dependent low bone attenuation and low-energy trauma in elderly females, which suggest the osteoporotic features of ankle fractures.

INTRODUCTION

This study was performed to investigate the osteoporotic features of ankle fracture in terms of bone attenuation and cause of injury.

METHODS

One hundred ninety-four patients (mean age 51.0 years, standard deviation 15.8 years; 98 males and 96 females) with ankle fracture were included. All patients underwent CT examination, and causes of injury (high/low-energy trauma) were recorded. Mean bone attenuations of the talus, medial malleolus, lateral malleolus, and distal tibial metaphysis were measured on CT images. Patients were divided into younger age (<50 years) and older age (≥50 years) groups, and mean bone attenuation and causes of injury were compared between the two groups in each gender.

RESULTS

Proportion of low-energy trauma was higher in the older age group than in the younger age group, but the difference was only significant in female gender (p = 0.011). The older age group showed significantly lower bone attenuation in the talus, medial malleolus, lateral malleolus, and distal tibial metaphysis than the younger age group in both genders. The older age group showed more complex pattern of fractures than the younger age group. With increasing age, bone attenuations tended to decrease and the difference of bone attenuation between the genders tended to increase in the talus, medial malleolus, lateral malleolus, and distal tibial metaphysis.

CONCLUSIONS

Ankle fracture had features of osteoporotic fracture that is characterized by age- and gender-dependent low bone attenuation. Ankle fracture should not be excluded from the clinical and research interest as well as from the benefit of osteoporosis management.

Validation of a scoring tool to predict drug-resistant pathogens in hospitalised pneumonia patients

BACKGROUND

Health care-associated pneumonia (HCAP) affects a heterogeneous group of patients in frequent contact with health care systems. However, HCAP criteria poorly predict infection with drug-resistant (DR) pathogens.

OBJECTIVE

To validate our previously reported risk-scoring model (predictive of DR pathogen infection) in patients admitted to hospital with pneumonia.

DESIGN

We evaluated 580 patients admitted with culture-positive bacterial pneumonia. We identified risk factors, evaluated the risk-scoring model's capacity to predict infection by DR pathogens and compared the model's diagnostic accuracy with that of current HCAP criteria.

RESULTS

DR pathogens were observed in 227/580 patients (39.1%). Of 269 HCAP patients, 153 (56.9%) were infected with DR pathogens. Overtreatment was more common in HCAP than in community-acquired pneumonia (58.7% vs. 41.2%, P < 0.001). Recent hospitalisation, admission from a long-term care facility, recent antibiotic treatment and tube feeding were independently associated with DR pathogens. For pathogen prediction, the risk-scoring model showed better diagnostic accuracy than HCAP criteria (area under receiver operating-characteristic curve = 0.723 vs. 0.673, P < 0.001).

CONCLUSION

According to current HCAP criteria, half of the HCAP patients were treated unnecessarily with broad-spectrum antibiotics. Risk scoring by stratifying risk factors could improve the identification of patients likely to be infected with DR pathogens.

Rapid and safe learning of robotic gastrectomy for gastric cancer: multidimensional analysis in a comparison with laparoscopic gastrectomy

BACKGROUND

The learning curve of robotic gastrectomy has not yet been evaluated in comparison with the laparoscopic approach. We compared the learning curves of robotic gastrectomy and laparoscopic gastrectomy based on operation time and surgical success.

METHODS

We analyzed 172 robotic and 481 laparoscopic distal gastrectomies performed by single surgeon from May 2003 to April 2009. The operation time was analyzed using a moving average and non-linear regression analysis. Surgical success was evaluated by a cumulative sum plot with a target failure rate of 10%. Surgical failure was defined as laparoscopic or open conversion, insufficient lymph node harvest for staging, resection margin involvement, postoperative morbidity, and mortality.

RESULTS

Moving average and non-linear regression analyses indicated stable state for operation time at 95 and 121 cases in robotic gastrectomy, and 270 and 262 cases in laparoscopic gastrectomy, respectively. The cumulative sum plot identified no cut-off point for surgical success in robotic gastrectomy and 80 cases in laparoscopic gastrectomy. Excluding the initial 148 laparoscopic gastrectomies that were performed before the first robotic gastrectomy, the two groups showed similar number of cases to reach steady state in operation time, and showed no cut-off point in analysis of surgical success.

CONCLUSIONS

The experience of laparoscopic surgery could affect the learning process of robotic gastrectomy. An experienced laparoscopic surgeon requires fewer cases of robotic gastrectomy to reach steady state. Moreover, the surgical outcomes of robotic gastrectomy were satisfactory.

Survival of hypoxic human mesenchymal stem cells is enhanced by a positive feedback loop involving miR-210 and hypoxia-inducible factor 1

The use of mesenchymal stem cells (MSCs) has emerged as a potential new treatment for myocardial infarction. However, the poor viability of MSCs after transplantation critically limits the efficacy of this new strategy. The expression of microRNA-210 (miR-210) is induced by hypoxia and is important for cell survival under hypoxic conditions. Hypoxia increases the levels of hypoxia inducible factor-1 (HIF-1) protein and miR-210 in human MSCs (hMSCs). miR-210 positively regulates HIF-1α activity. Furthermore, miR-210 expression is also induced by hypoxia through the regulation of HIF-1α. To investigate the effect of miR-210 on hMSC survival under hypoxic conditions, survival rates along with signaling related to cell survival were evaluated in hMSCs over-expressing miR-210 or ones that lacked HIF-1α expression. Elevated miR-210 expression increased survival rates along with Akt and ERK activity in hMSCs with hypoxia. These data demonstrated that a positive feedback loop involving miR-210 and HIF-1α was important for MSC survival under hypoxic conditions.

The responses of multiple cytokines following incubation of whole blood from TB patients, latently infected individuals and controls with the TB antigens ESAT-6, CFP-10 and TB7.7

The development of clinically relevant biomarkers is important for diagnosing latent tuberculosis infection (LTBI) and active tuberculosis (TB) and predicting their prognoses. This study examined whether the responses of multiple cytokines can be used as a biomarker to distinguish the TB infection status and mycobacterial load. We analysed the responses of multiple cytokines (IFN-γ, IL-2, IL-10, IL-13, IL-17 and TNF-α) in the supernatant from the QuantiFERON-TB Gold In-Tube assay following stimulation of whole blood from the TB group (n = 32), LTBI group (n = 19) and healthy controls (n = 30) with TB antigens (ESAT-6, CFP-10 and TB7.7). The median responses of IFN-γ, IL-2, IL-10 and IL-13 were higher in the LTBI and active TB groups than in the non-TB control group (IFN-γ, P < 0.001; IL-2, P < 0.001; IL-10, P = 0.012; IL-13, P < 0.001). The median IL-2/IFN-γ ratio of the LTBI group was higher than that of the active TB group (P = 0.014) and differed significantly between patients with LTBI, patients with smear-negative TB and patients with smear-positive TB (P = 0.027). This difference was especially evident between the patients with LTBI and patients with smear-positive TB (P = 0.047). In conclusion, IFN-γ, IL-2, IL-10 and IL-13 can serve as biomarkers for distinguishing TB infection. In addition, the IL-2/IFN-γ ratio appears to be a biomarker for diagnosing LTBI and may be useful as a prognostic factor and for evaluating treatment responses.

Conversion rates of an interferon-γ release assay and the tuberculin skin test in the serial monitoring of healthcare workers

PURPOSE

Regular monitoring of latent tuberculosis (TB) infection in healthcare workers (HCWs) is recommended, but the view about the effective method and performance of serial monitoring is controversial. The aim of this study was to determine differences in conversion rates according to TB exposure risk using the tuberculin skin test (TST) and the QuantiFERON-TB Gold In-Tube (QFT-GIT), and to evaluate the reproducibility and within-subject variability of the QFT-GIT in South Korea.

METHODS

Fifty-three HCWs were grouped according to their risk for TB exposure: group 1, high risk (n = 21); group 2, low risk (n = 32). Baseline and follow-up TSTs and QFT-GITs were performed from June 2009 to July 2011. Enzyme-linked immunosorbent assays (ELISAs) were repeated for the second QFT-GIT and a third QFT-GIT was performed after 8 weeks when discordant results of the second TST and QFT-GIT or a conversion or reversion were observed.

RESULTS

No difference in the QFT-GIT conversion rate was evident between the two groups (15.4 vs. 6.5 %, p = 0.57), and no TST conversion was observed. The rate of QFT-GIT positivity was higher in the high-risk group (first QFT-GIT: 38.1 vs. 3.1 %, p = 0.002; second QFT-GIT: 33.3 vs. 9.4 %, p = 0.039). The re-test reproducibility of QFT-GIT results was high (100 %), and the within-subject results of repetitive QFT-GITs were variable.

CONCLUSIONS

Stricter prevention strategies remain necessary in HCWs at high risk of TB exposure, and serial interferon-γ release assays (IGRAs) should be interpreted with caution in HCWs.

A decision tree-based approach for identifying urban-rural differences in metabolic syndrome risk factors in the adult Korean population

AIM

The purpose of this study was to explore the difference in the pattern of metabolic syndrome (MetS) in urban and rural populations in Korea using data mining techniques.

SUBJECTS AND METHODS

In total, 1013 adults >30 yr of age from urban (184 males and 313 females) and rural districts (211 males and 305 females) were recruited from Gyeongsangnam-do, Korea. Modified National Cholesterol Education Program Adult Treatment Panel III criteria were used to identify individuals with MetS. We applied a decision tree analysis to elucidate the differences in the clustering of MetS components between the urban and rural populations.

RESULTS

The prevalence of MetS was 33.2% and 35.2% in urban and rural districts, respectively (p=0.598). The decision-tree approach revealed that the combination of high serum triglycerides (TG) + high systolic blood pressure (SBP), high TG + low HDL cholesterol, and high waist circumference (WC) + high SBP + high fasting plasma glucose (FPG) were strong predictors of MetS in the urban population, whereas the combination of TG + SBP + WC and SBP + WC + FPG showed high positive predictive value for the presence of MetS in the rural population.

CONCLUSIONS

Although no significant difference was found for the prevalence of MetS between the two populations, the differences in the clustering pattern of MetS components in urban and rural districts in Korea were identified by decision tree analysis. Our findings may serve as a basis to design necessary population-based intervention programs for prevention and progression of MetS and its complications in Korea.

Partial splenic artery embolization for thrombocytopenia and uncontrolled massive ascites after liver transplantation

Thrombocytopenia (platelet < 60,000/mm(3)) and uncontrolled massive ascites (ascitic fluid > 1000 mL/d over 10 days) after liver transplantation (OLT), although uncommon, usually represent serious complications. Splenectomy is a useful treatment despite its many side effects. Recently, partial splenic artery embolization (PSAE) is considered to be a nonsurgical, less invasive treatment. In this study, we retrospectively reviewed the results of PSAE after OLT. Between October 2008 and February 2010, 11 patients underwent PSAE after OLT due to thrombocytopenia (n = 6) or refractory ascites (RA; n = 5). Six patients (54.5%) were males and 3 (27.3%) were children. The primary liver disease was virus-related liver cirrhosis (n = 6), biliary atresia (n = 3), fulminant hepatitis (n = 1), or alcoholic liver cirrhosis (n = 1). Seven grafts were from living and four from deceased donors. The major axial size of spleen was 12.1 to 23.4 cm and its average embolized volume, 76.4% (range = 70%-80%). As the result, the platelet count significantly increased after PSAE in all patients maintaining values greater than 100,000/mm(3) in four thrombocytopenic patients (66.7%). Cases of RA showed marked decreases after PSAE (100%). The follow-up was 6 to 28 months. After PSAE, patients experienced abdominal pain (n = 9, 81.8%), fever (n = 2, 18.2%), and abdominal distension (n = 2, 18.2%). However, there was no serious complication after PSAE such as splenic abscess, rupture, pancreatic infarction, sepsis, or death. In conclusion, PSAE was effective and safe and can be the choice for thrombocytopenia or RA related to hypersplenism after OLT.

Phorbol myristate acetate differentiates human adipose-derived mesenchymal stem cells into functional cardiogenic cells

To achieve effective regeneration of injured myocardium, it is important to find physiological way of improving the cardiogenic differentiation of stem cells. Previous studies demonstrated that cardiomyocytes from bone marrow-derived mesenchymal stem cells (BMSCs) activated with phorbolmyristate acetate (PMA), a protein kinase C (PKC) activator, restore electromechanical function in infarcted rat hearts. In this study, we investigated the effect of PMA on cardiogenic differentiation of adipose-derived MSCs (ASCs) for clinical applications. To confirm the effect of PMA, ASCs treated with 1μM PMA were grown for nine days. The expression of cardiac-specific markers (cardiac troponin T, myosin light chain, myosin heavy chain) in PMA-treated MSCs was demonstrated by immunocytochemistry. Alhough few α(1A) receptors exist in ASCs, α(1)-adrenergic receptor subtypes were preferentially expressed in PMA-treated ASCs. Moreover, expression of the β-adrenergic and muscarinic receptors increased in PMA-treated ASCs compared to normal cells. The mRNA levels of Ca(2+)-related factors (SERCA 2a; sarcoplasmic reticulum Ca(2+)-ATPase, LTCC; L-type Ca(2+) channel) in treated ASCs were similar to the levels in cardiomyocytes. Following the transplantation of chemically activated cardiogenic ASCs into infarcted myocardium, histological analysis showed that infarct size, interstitial fibrosis, and apoptotic index were markedly decreased and cardiac function was restored. In conclusion, PMA might induce the cardiogenic differentiation of human ASCs as well as BMSCs. This result suggests successful use of human ASCs in cardiac regeneration therapy.

Electroacupuncture enhances motor recovery performance with brain-derived neurotrophic factor expression in rats with cerebral infarction

OBJECTIVE

Electroacupuncture (EA) is a traditional medicine in patients with post-stroke rehabilitation. Brain-derived neurotrophic factor (BDNF) is a potent growth factor involved in recovery following cerebral injury. The aim of the present study was to investigate whether EA increases BDNF levels and facilitates functional recovery.

METHODS

Occlusion of the middle cerebral artery was performed in rats (N=12) followed by reperfusion. EA was applied at the GV20 (Baihui) acupoint. Motor and sensory functions were monitored on the Garcia scale for 2 weeks. Expressions of BDNF and receptor tyrosine kinase B (trkB) were determined by immunoblotting and immunohistochemistry.

RESULTS

Improvement of Garcia scores, particularly in motor performance, were noted in the group with EA stimulation (p<0.05). With EA application, BDNF was elevated in the ischaemic hemisphere with increased numbers of BDNF(+) cells. Increased expression of trkB was also detected.

CONCLUSION

These results indicate that EA at GV20 improves motor recovery and stimulates BDNF/trkB expression in rats with cerebral ischaemia.