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Abdallah LE, Abusubha A, Lee BH, Badami A, Abood G, Knab LM, Jr WS, Refaat T. Treatment Outcomes and Toxicity Profile of MRI-Guided Gated-Real Time Online Adaptive Stereotactic Body Radiotherapy to Patients with Pancreatic Tumors. Int J Radiat Oncol Biol Phys 2023; 117:e281. [PMID: 37785052 DOI: 10.1016/j.ijrobp.2023.06.1263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) Stereotactic body radiation therapy (SBRT) to patients with inoperable pancreas cancer has shown promising outcomes. Dose escalation is challenging given the associated risks to nearby organs at risk and requires treatment plan adaptation and motion management. This study reports the treatment related adverse events and treatment outcomes of MRI-guided SBRT utilizing gated-real time online adaptive radiotherapy to patients with pancreatic tumors. MATERIALS/METHODS This is a single institution retrospective IRB approved study and included patients with pancreatic tumors who were treated with MRI-guided SBRT utilizing gated-real time online adaptive radiotherapy, consecutively between 2019 and 2022. All patients were treated with 0.35T MRI linear accelerator. All patients' charts and radiation plans were reviewed for this study. RESULTS The study included 25 patients treated consecutively to 125 radiation fractions with MRI-guided SBRT. The study included 15 females and 10 males, 19 white, 2 Asians, 1 Latin American and 2 African Americans. The median age was 74, and all patients had pancreatic adenocarcinoma (92%) except two patients who had biopsy proven renal cell carcinoma metastatic to the pancreas without evidence of disease elsewhere. Most patients (68%) received chemotherapy (FOLFIRINOX or Gemcitabine / Protein-bound paclitaxel) prior to SBRT. The median dose to gross target volume (GTV) was 50 Gy, and to planning target volume (PTV) was 35 Gy. All patients were treated in 5 radiation fractions. Thirteen patients (52%) received elective nodal irradiation (ENI). All patients had at least a single real-time online adaptive replanning (median 3 fractions, range 1-5 fractions). All treatment fractions were gated (100%) with MRI guidance. The 1-, 2-, & 3- year local-regional control (LRC) were 81%, 57%, & 57% respectively (Median 16 months). The 1-, 2-, & 3- year Distant Control (DC) were 81%, 74%, & 56% respectively (Median 14 months). The 1-, 2-, 3-year overall survival (OS) were 77%, 35%, & 24% (Median 21 months). Planning Target Volume (PTV) dose ≥40Gy was significantly associated with improved local-regional control (p = 0.02). Gross Target Volume (GTV) dose <50Gy was significantly associated with lower DC (p = 0.03). ENI showed a trend towards improved local-regional control but was not statistically significant (p = 0.1). None of the patients experienced ≥ grade 3 toxicities. Most common adverse event were grades 1 or 2 fatigue (24%), nausea (16%), and abdominal discomfort (12%). CONCLUSION In this cohort, MRI-guided SBRT utilizing gated-real time online adaptive radiotherapy was a safe and effective approach for patients with pancreatic tumors who are not surgical candidates. In this study, dose escalation was significantly associated with improved local-regional (PTV ≥40 Gy) and distant control (GTV ≥50Gy). None of the patients experienced grade ≥3 radiation induced adverse events.
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Wang X, Leng S, Lu Z, Huang S, Lee BH, Baskaran L, Yew MS, Teo L, Chan MY, Ngiam KY, Lee HK, Zhong L, Huang W. Context-aware deep network for coronary artery stenosis classification in coronary CT angiography. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2023; 2023:1-4. [PMID: 38083399 DOI: 10.1109/embc40787.2023.10340650] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Automatic coronary artery stenosis grading plays an important role in the diagnosis of coronary artery disease. Due to the difficulty of learning the informative features from varying grades of stenosis, it is still a challenging task to identify coronary artery stenosis from coronary CT angiography (CCTA). In this paper, we propose a context-aware deep network (CADN) for coronary artery stenosis classification. The proposed method integrates 3D CNN with Transformer to improve the feature representation of coronary artery stenosis in CCTA. We evaluate the proposed method on a multicenter dataset (APOLLO study with NCT05509010). Experimental results show that our proposed method can achieve the accuracy of 0.84, 0.83, and 0.86 for stenosis diagnosis on the lesion, artery, and patient levels, respectively.
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Yoo H, Jang JS, Shin SW, Lee J, Kim J, Kim DM, Lee IJ, Lee BH, Park J, Kim JH. Influence of the Reaction Pathway on the Defect Formation in a Cu 2ZnSnSe 4 Thin Film. ACS APPLIED MATERIALS & INTERFACES 2021; 13:13425-13433. [PMID: 33706505 DOI: 10.1021/acsami.1c01307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Point defect engineering in Cu2ZnSnSe4 (CZTSe) thin films is the main issue to improve its device performance. This study reveals the correlation between the reaction pathway and the point defects in the CZTSe film. The reaction pathway from a metallic precursor (Mo/Zn/Sn/Cu) to a kesterite CZTSe film is varied by changing the annealing process. The synthesized CZTSe films under different reaction pathways induce different device performances with different defect energy levels, although all CZTSe films have similar structural and optical properties (Eg ∼ 1.0 eV). The admittance spectroscopy demonstrates the correlations between point defect types (VZn, ZnSn, ZnCu, CuZn, and VCu) and the reaction pathways for the formation of CZTSe films. The different growth rates of binary selenides, such as ZnSe and/or Sn-Se phases, during the annealing process are especially strongly related to the formation of point defects, leading to the different open-circuit voltages (396-451 mV) and fill factors (51-65%). The results of this study suggest that controlling the reaction pathway is an effective approach to adjust the formation of defects in the kesterite CZTSe film as well as to fabricate high-performance solar cell devices.
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Lee SB, Park Y, Kim DW, Kwon JW, Ha JW, Yang JH, Lee BH, Suk KS, Moon SH, Kim HS, Lee HM. Association between mortality risk and the number, location, and sequence of subsequent fractures in the elderly. Osteoporos Int 2021; 32:233-241. [PMID: 32820370 DOI: 10.1007/s00198-020-05602-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 08/13/2020] [Indexed: 12/16/2022]
Abstract
UNLABELLED The mortality risk showed a positive correlation as the number of subsequent fractures increased. Hip fracture showed the greatest association with mortality risk, followed by vertebral fracture. For the combination of hip and vertebral fracture, a hip fracture after a vertebral fracture showed the highest mortality risk. INTRODUCTION It is unclear whether subsequent fractures or a certain location and sequence of subsequent fractures are associated with mortality risk in the elderly. We aimed to investigate the relationship between subsequent fractures and mortality risk. METHODS Using the Korean National Health Insurance Research Database, we analyzed the cohort data of 24,756 patients aged > 60 years who sustained fractures between 2002 and 2013. Cox regression was used to assess the mortality risk associated with the number, locations, and sequences of subsequent fractures. RESULTS Mortality hazard ratios (HRs) for women and men were shown to be associated with the number of subsequent fractures (one, 1.63 (95% confidence interval [CI], 1.48-1.80) and 1.42 (95% CI, 1.28-1.58); two, 1.75 (95% CI, 1.47-2.08) and 2.03 (95% CI, 1.69-2.43); three or more, 2.46(95% CI, 1.92-3.15) and 1.92 (95% CI, 1.34-2.74), respectively). For women, the mortality risk was high when hip (HR, 2.49; 95% CI, 1.80-3.44) or vertebral (HR, 1.40; 95% CI, 1.03-1.90) fracture occurred as a second fracture. Compared with a single hip fracture, there was a high mortality risk in the group with hip fracture after the first vertebral fracture (HR, 2.90; 95% CI, 1.86-4.54), followed by vertebral fracture after the first hip fracture (HR, 1.90; 95% CI, 1.12-3.22). CONCLUSION The mortality risk showed a positive correlation as the number of subsequent fractures increased. Hip fracture showed the greatest association with mortality risk, followed by vertebral fracture. For the combination of hip and vertebral fracture, a hip fracture after a vertebral fracture showed the highest mortality risk.
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Gang MG, Karade VC, Suryawanshi MP, Yoo H, He M, Hao X, Lee IJ, Lee BH, Shin SW, Kim JH. A Facile Process for Partial Ag Substitution in Kesterite Cu 2ZnSn(S,Se) 4 Solar Cells Enabling a Device Efficiency of over 12. ACS APPLIED MATERIALS & INTERFACES 2021; 13:3959-3968. [PMID: 33463150 DOI: 10.1021/acsami.0c19373] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
A cation substitution in Cu2ZnSn(S,Se)4 (CZTSSe) offers a viable strategy to reduce the open-circuit voltage (Voc)-deficit by altering the characteristics of band-tail states, antisite defects, and related defect clusters. Herein, we report a facile single process, i.e., simply introducing a thin Ag layer on a metallic precursor, to effectively improve the device characteristics and performances in kesterite (Agx,Cu1-x)2ZnSn(Sy,Se1-y)4 (ACZTSSe) solar cells. Probing into the relationship between the external quantum efficiency derivative (dEQE/dλ) and device performances revealed the Voc-deficit characteristics in the ACZTSSe solar cells as a function of Cu and Ag contents. The fabricated champion ACZTSSe solar cell device showed an efficiency of 12.07% and a record low Voc-deficit of 561 mV. Thorough investigations into the mechanism underpinning the improved performance in the ACZTSSe device further revealed the improved band-tailing characteristic, effective minority carrier lifetime, and diode factors as well as reduced antisite defects and related defect clusters as compared to the CZTSSe device. This study demonstrates the feasibility of effectively suppressing antisite defects, related defect clusters, and band-tailing characteristics by simply introducing a thin Ag layer on a metallic precursor in the kesterite solar cells, which in turn effectively reduces the Voc-deficit.
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Jayaram P, Liu C, Dawson B, Ketkar S, Patel SJ, Lee BH, Grol MW. Leukocyte-dependent effects of platelet-rich plasma on cartilage loss and thermal hyperalgesia in a mouse model of post-traumatic osteoarthritis. Osteoarthritis Cartilage 2020; 28:1385-1393. [PMID: 32629163 PMCID: PMC7787501 DOI: 10.1016/j.joca.2020.06.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Revised: 06/14/2020] [Accepted: 06/22/2020] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Platelet-rich plasma (PRP) is an emerging therapeutic strategy for treatment of osteoarthritis (OA); however, there is a lack of preclinical and clinical evidence for its efficacy and its mechanism of action is unclear. In the current study, we utilized leukocyte poor-PRP (LP-PRP) and leukocyte rich-PRP (LR-PRP) to mimic clinical point of care formulations and assessed their potential to alter disease progression in a mouse model of post-traumatic OA. METHOD Three-month-old wild-type male FVB/N mice received destabilization of the medial meniscus (DMM) surgery to induce OA. To assess the efficacy of LP-PRP and LR-PRP, mice were given intraarticular injections at 2-, 7- and 28-days post-surgery. Mice were then assessed at 5-, 9-, and 13-weeks post-surgery for changes in chronic pain using the hot plate nociceptive assay. At 14-weeks, OA pathogenesis was evaluated using histology and phase-contrast μCT. RESULTS Treatment with LP-PRP and to a lesser extent LR-PRP preserved cartilage volume and surface area compared to phosphate-buffered saline (PBS) as measured by phase-contrast μCT. However, both treatments had higher Osteoarthritis Research Society International (OARSI) and synovitis scores compared to sham, and neither substantially improved scores compared to PBS controls. With respect to thermal hyperalgesia, PBS-treated mice displayed reduced latency to response compared to sham, and LR-PRP but not LP-PRP improved latency to response at 5-, 9- and 13-weeks post-surgery compared to PBS. CONCLUSION The results of this study suggest that effects of PRP therapy on OA progression and disease-induced hyperalgesia may be leukocyte-dependent. And while LP-PRP and to a lesser extent LR-PRP protect from volume and surface loss, significant pathology is still seen within OA joints. Future work is needed to understand how the different components of PRP effect OA pathogenesis and pain, and how these could be modified to achieve greater therapeutic efficacy.
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Lee BH, Massa AT, Taylor KR. Accessory Tragus: A Rare Congenital Anomaly in a Dog. J Comp Pathol 2020; 179:79-82. [PMID: 32958153 DOI: 10.1016/j.jcpa.2020.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 07/20/2020] [Indexed: 10/23/2022]
Abstract
Accessory tragus is a congenital malformation of part of the external ear, commonly reported in humans. Clinically, it is a benign, cutaneous mass located anywhere between the tragus of the ear and the angle of the mouth, along the migratory path of the first branchial arch. An accessory tragus was diagnosed in an otherwise healthy six-month-old male castrated American pit bull terrier that had a haired, pedunculated cutaneous mass on the left maxillary region from birth. Histologically, the mass was a polypoid extension of histologically normal haired skin with a central core of subcutaneous adipose tissue and well-differentiated elastic cartilage. To the authors' knowledge, this is the first report of this lesion in a non-human species. Retrospective examination of records from 2008 to 2018 at the Washington Animal Disease Diagnostic Laboratory failed to identify any other case. As accessory tragus in humans is commonly linked with other congenital anomalies and syndromes, recognition of this lesion in animals may aid in early discovery of other congenital defects and inform adequate excision of the lesion to prevent chondrodermatitis.
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Kim JO, Lee J, Lee BH. Effect of Scapular Stabilization Exercise during Standing on Upper Limb Function and Gait Ability of Stroke Patients. J Neurosci Rural Pract 2019; 8:540-544. [PMID: 29204011 PMCID: PMC5709874 DOI: 10.4103/jnrp.jnrp_464_16] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Background The purpose of this study was to determine the effect of scapular stabilization exercise during standing on a paretic side on upper limb function and gait ability of stroke patients. Methods This study was a hospital-based, randomized controlled trial with a blinded assessor. A total of 17 patients with hemiplegic diagnosis after stroke were divided into two groups (9 patients in a study group and 8 patients in a control group). The study group received physical therapy and scapular stabilization exercise on a paretic side. Participants were subjected to initial evaluation before the treatment. Subjects were subsequently re-evaluated 4 and 8 weeks later to compare the changes. Measurements of hand function and gait ability were performed. Results Based on multivariate analysis of variance for repeated-measures, there was a significant time effect for Timed Up and Go test (TUG) (F = 13.816, P = 0.000), Functional Gait Assessment (FGA) (F = 18.613, P = 0.000), and manual function test (MFT) (F = 16.777, P = 0.000). The group × time interaction effect was also significant for FGA (F = 4.966, P = 0.024) and MFT (F = 6.946, P = 0.003), but not for TUG test (F = 3.343, P = 0.069). Conclusion Results of the present study indicated that scapular stabilization exercise during standing on a paretic side for 8 weeks had an effect on hand function and gait ability of hemiplegic patients after stroke. Further studies are needed to find the most proper exercise for stroke patients who have gait disability and upper limb dysfunction.
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Lee BH, Ho SW, Kau CY. Surgical Fixation of a Comminuted Inter-Trochanteric Fracture in a Patient with Bilateral Below Knee Amputation. Malays Orthop J 2018; 12:54-56. [PMID: 29725516 PMCID: PMC5920262 DOI: 10.5704/moj.1803.013] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Surgical fixation of hip fractures in patients with below knee amputation is challenging due to the difficulty in obtaining optimal traction for reduction of the fracture. Surgeons may face difficulty in positioning such patients on the traction table due to the absence of the foot and distal lower limb. There are several techniques described to overcome this technical difficulty. In this case report, we present a case of a 64-year old gentleman with bilateral below knee amputation presenting with a comminuted right intertrochanteric fracture. We highlight a simple and effective method of applying skin traction to obtain adequate reduction for hip fracture fixation.
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Ghassemi Nejad J, Sung KI, Lee BH, Peng JL, Kim JY, Chemere B, Oh SM, Kim MJ, Kim SC, Kim BW. 3 Comparison of hair cortisol levels and body temperature response prior to and post heat stress and water deprivation in Holstein dairy cows. J Anim Sci 2018. [DOI: 10.1093/jas/sky073.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Park HC, Kim MJ, Lee BH. Randomized clinical trial of antibiotic therapy for uncomplicated appendicitis. Br J Surg 2017; 104:1785-1790. [DOI: 10.1002/bjs.10660] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2017] [Revised: 06/19/2017] [Accepted: 06/30/2017] [Indexed: 11/05/2022]
Abstract
Abstract
Background
Uncomplicated appendicitis may resolve spontaneously or require treatment with antibiotics or appendicectomy. The aim of this randomized trial was to compare the outcome of a non-antibiotic management strategy with that of antibiotic therapy in uncomplicated appendicitis.
Methods
Patients presenting to a university teaching hospital with CT-verified uncomplicated simple appendicitis (appendiceal diameter no larger than 11 mm and without any signs of perforation) were randomized to management with a no-antibiotic regimen with supportive care (intravenous fluids, analgesia and antipyretics as necessary) or a 4-day course of antibiotics with supportive care. The primary endpoint was rate of total treatment failure, defined as initial treatment failure within 1 month and recurrence of appendicitis during the follow-up period.
Results
Some 245 patients were randomized within the trial, and followed up for a median of 19 months. The duration of hospital stay was shorter (mean 3·1 versus 3·7 days; P < 0·001) and the medical costs lower (€1181 versus 1348; P < 0·001) among those randomized to therapy without antibiotics. There was no difference in total treatment failure rate between the groups: 29 of 124 (23·4 per cent) in the no-antibiotic group and 25 of 121 (20·7 per cent) in the antibiotic group (P = 0·609). Eighteen patients (9 in each group) had initial treatment failure, 15 of whom underwent appendicectomy and three received additional antibiotics. Thirty-six patients (20 in the no-antibiotic group, 16 in the antibiotic group) experienced recurrence, of whom 30 underwent appendicectomy and six received further antibiotics.
Conclusion
Treatment failure rates in patients presenting with CT-confirmed uncomplicated appendicitis appeared similar among those receiving supportive care with either a no-antibiotic regimen or a 4-day course of antibiotics. Registration number: KCT0000124 (http://cris.nih.go.kr).
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Elf S, Lin R, Xia S, Pan Y, Shan C, Wu S, Lonial S, Gaddh M, Arellano ML, Khoury HJ, Khuri FR, Lee BH, Boggon TJ, Fan J, Chen J. Targeting 6-phosphogluconate dehydrogenase in the oxidative PPP sensitizes leukemia cells to antimalarial agent dihydroartemisinin. Oncogene 2016; 36:254-262. [PMID: 27270429 PMCID: PMC5464402 DOI: 10.1038/onc.2016.196] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 04/19/2016] [Accepted: 04/24/2016] [Indexed: 12/13/2022]
Abstract
The oxidative pentose phosphate pathway (PPP) is crucial for cancer cell metabolism and tumor growth. We recently reported that targeting a key oxidative PPP enzyme, 6-phosphogluconate dehydrogenase (6PGD), using our novel small molecule 6PGD inhibitors Physcion and its derivative S3, shows anti-cancer effects. Notably, humans with genetic deficiency of either 6PGD or another oxidative PPP enzyme, glucose-6-phosphate dehydrogenase (G6PD), exhibit non-immune hemolytic anemia upon exposure to aspirin and various anti-malarial drugs. Inspired by these clinical observations, we examined the anti-cancer potential of combined treatment with 6PGD inhibitors and anti-malarial drugs. We found that stable knockdown of 6PGD sensitizes leukemia cells to anti-malarial agent dihydroartemisinin (DHA). Combined treatment with DHA and Physcion activates AMP-activated protein kinase, leading to synergistic inhibition of human leukemia cell viability. Moreover, our combined therapy synergistically attenuates tumor growth in xenograft nude mice injected with human K562 leukemia cells and cell viability of primary leukemia cells from human patients, but shows minimal toxicity to normal hematopoietic cells in mice as well as red blood cells and mononucleocytes from healthy human donors. Our findings reveal the potential for combined therapy using optimized doses of Physcion and DHA as a novel anti-leukemia treatment without inducing hemolysis.
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Lopez-Hilfiker FD, Mohr C, D'Ambro EL, Lutz A, Riedel TP, Gaston CJ, Iyer S, Zhang Z, Gold A, Surratt JD, Lee BH, Kurten T, Hu WW, Jimenez J, Hallquist M, Thornton JA. Molecular Composition and Volatility of Organic Aerosol in the Southeastern U.S.: Implications for IEPOX Derived SOA. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:2200-9. [PMID: 26811969 DOI: 10.1021/acs.est.5b04769] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
We present measurements as part of the Southern Oxidant and Aerosol Study (SOAS) during which atmospheric aerosol particles were comprehensively characterized. We present results utilizing a Filter Inlet for Gases and AEROsol coupled to a chemical ionization mass spectrometer (CIMS). We focus on the volatility and composition of isoprene derived organic aerosol tracers and of the bulk organic aerosol. By utilizing the online volatility and molecular composition information provided by the FIGAERO-CIMS, we show that the vast majority of commonly reported molecular tracers of isoprene epoxydiol (IEPOX) derived secondary organic aerosol (SOA) is derived from thermal decomposition of accretion products or other low volatility organics having effective saturation vapor concentrations <10(-3) μg m(-3). In addition, while accounting for up to 30% of total submicrometer organic aerosol mass, the IEPOX-derived SOA has a higher volatility than the remaining bulk. That IEPOX-SOA, and more generally bulk organic aerosol in the Southeastern U.S. is comprised of effectively nonvolatile material has important implications for modeling SOA derived from isoprene, and for mechanistic interpretations of molecular tracer measurements. Our results show that partitioning theory performs well for 2-methyltetrols, once accretion product decomposition is taken into account. No significant partitioning delays due to aerosol phase or viscosity are observed, and no partitioning to particle-phase water or other unexplained mechanisms are needed to explain our results.
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Wolfe GM, Kaiser J, Hanisco TF, Keutsch FN, de Gouw JA, Gilman JB, Graus M, Hatch CD, Holloway J, Horowitz LW, Lee BH, Lerner BM, Lopez-Hilifiker F, Mao J, Marvin MR, Peischl J, Pollack IB, Roberts JM, Ryerson TB, Thornton JA, Veres PR, Warneke C. Formaldehyde production from isoprene oxidation across NO x regimes. ATMOSPHERIC CHEMISTRY AND PHYSICS 2016. [PMID: 29619046 DOI: 10.5194/acp-16-2597-] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
The chemical link between isoprene and formaldehyde (HCHO) is a strong, non-linear function of NOx (= NO + NO2). This relationship is a linchpin for top-down isoprene emission inventory verification from orbital HCHO column observations. It is also a benchmark for overall photochemical mechanism performance with regard to VOC oxidation. Using a comprehensive suite of airborne in situ observations over the Southeast U.S., we quantify HCHO production across the urban-rural spectrum. Analysis of isoprene and its major first-generation oxidation products allows us to define both a "prompt" yield of HCHO (molecules of HCHO produced per molecule of freshly-emitted isoprene) and the background HCHO mixing ratio (from oxidation of longer-lived hydrocarbons). Over the range of observed NOx values (roughly 0.1 - 2 ppbv), the prompt yield increases by a factor of 3 (from 0.3 to 0.9 ppbv ppbv-1), while background HCHO increases by a factor of 2 (from 1.6 to 3.3 ppbv). We apply the same method to evaluate the performance of both a global chemical transport model (AM3) and a measurement-constrained 0-D steady state box model. Both models reproduce the NOx dependence of the prompt HCHO yield, illustrating that models with updated isoprene oxidation mechanisms can adequately capture the link between HCHO and recent isoprene emissions. On the other hand, both models under-estimate background HCHO mixing ratios, suggesting missing HCHO precursors, inadequate representation of later-generation isoprene degradation and/or under-estimated hydroxyl radical concentrations. Detailed process rates from the box model simulation demonstrate a 3-fold increase in HCHO production across the range of observed NOx values, driven by a 100% increase in OH and a 40% increase in branching of organic peroxy radical reactions to produce HCHO.
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Warneke C, Trainer M, de Gouw JA, Parrish DD, Fahey DW, Ravishankara AR, Middlebrook AM, Brock CA, Roberts JM, Brown SS, Neuman JA, Lerner BM, Lack D, Law D, Hübler G, Pollack I, Sjostedt S, Ryerson TB, Gilman JB, Liao J, Holloway J, Peischl J, Nowak JB, Aikin K, Min KE, Washenfelder RA, Graus MG, Richardson M, Markovic MZ, Wagner NL, Welti A, Veres PR, Edwards P, Schwarz JP, Gordon T, Dube WP, McKeen S, Brioude J, Ahmadov R, Bougiatioti A, Lin JJ, Nenes A, Wolfe GM, Hanisco TF, Lee BH, Lopez-Hilfiker FD, Thornton JA, Keutsch FN, Kaiser J, Mao J, Hatch C. Instrumentation and Measurement Strategy for the NOAA SENEX Aircraft Campaign as Part of the Southeast Atmosphere Study 2013. ATMOSPHERIC MEASUREMENT TECHNIQUES 2016. [PMID: 29619117 DOI: 10.5194/amt-2015-388] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Natural emissions of ozone-and-aerosol-precursor gases such as isoprene and monoterpenes are high in the southeast of the US. In addition, anthropogenic emissions are significant in the Southeast US and summertime photochemistry is rapid. The NOAA-led SENEX (Southeast Nexus) aircraft campaign was one of the major components of the Southeast Atmosphere Study (SAS) and was focused on studying the interactions between biogenic and anthropogenic emissions to form secondary pollutants. During SENEX, the NOAA WP-3D aircraft conducted 20 research flights between 27 May and 10 July 2013 based out of Smyrna, TN. Here we describe the experimental approach, the science goals and early results of the NOAA SENEX campaign. The aircraft, its capabilities and standard measurements are described. The instrument payload is summarized including detection limits, accuracy, precision and time resolutions for all gas-and-aerosol phase instruments. The inter-comparisons of compounds measured with multiple instruments on the NOAA WP-3D are presented and were all within the stated uncertainties, except two of the three NO2 measurements. The SENEX flights included day- and nighttime flights in the Southeast as well as flights over areas with intense shale gas extraction (Marcellus, Fayetteville and Haynesville shale). We present one example flight on 16 June 2013, which was a daytime flight over the Atlanta region, where several crosswind transects of plumes from the city and nearby point sources, such as power plants, paper mills and landfills, were flown. The area around Atlanta has large biogenic isoprene emissions, which provided an excellent case for studying the interactions between biogenic and anthropogenic emissions. In this example flight, chemistry in and outside the Atlanta plumes was observed for several hours after emission. The analysis of this flight showcases the strategies implemented to answer some of the main SENEX science questions.
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Warneke C, Trainer M, de Gouw JA, Parrish DD, Fahey DW, Ravishankara AR, Middlebrook AM, Brock CA, Roberts JM, Brown SS, Neuman JA, Lerner BM, Lack D, Law D, Hübler G, Pollack I, Sjostedt S, Ryerson TB, Gilman JB, Liao J, Holloway J, Peischl J, Nowak JB, Aikin K, Min KE, Washenfelder RA, Graus MG, Richardson M, Markovic MZ, Wagner NL, Welti A, Veres PR, Edwards P, Schwarz JP, Gordon T, Dube WP, McKeen S, Brioude J, Ahmadov R, Bougiatioti A, Lin JJ, Nenes A, Wolfe GM, Hanisco TF, Lee BH, Lopez-Hilfiker FD, Thornton JA, Keutsch FN, Kaiser J, Mao J, Hatch C. Instrumentation and Measurement Strategy for the NOAA SENEX Aircraft Campaign as Part of the Southeast Atmosphere Study 2013. ATMOSPHERIC MEASUREMENT TECHNIQUES 2016; 9:3063-3093. [PMID: 29619117 PMCID: PMC5880326 DOI: 10.5194/amt-9-3063-2016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Natural emissions of ozone-and-aerosol-precursor gases such as isoprene and monoterpenes are high in the southeast of the US. In addition, anthropogenic emissions are significant in the Southeast US and summertime photochemistry is rapid. The NOAA-led SENEX (Southeast Nexus) aircraft campaign was one of the major components of the Southeast Atmosphere Study (SAS) and was focused on studying the interactions between biogenic and anthropogenic emissions to form secondary pollutants. During SENEX, the NOAA WP-3D aircraft conducted 20 research flights between 27 May and 10 July 2013 based out of Smyrna, TN. Here we describe the experimental approach, the science goals and early results of the NOAA SENEX campaign. The aircraft, its capabilities and standard measurements are described. The instrument payload is summarized including detection limits, accuracy, precision and time resolutions for all gas-and-aerosol phase instruments. The inter-comparisons of compounds measured with multiple instruments on the NOAA WP-3D are presented and were all within the stated uncertainties, except two of the three NO2 measurements. The SENEX flights included day- and nighttime flights in the Southeast as well as flights over areas with intense shale gas extraction (Marcellus, Fayetteville and Haynesville shale). We present one example flight on 16 June 2013, which was a daytime flight over the Atlanta region, where several crosswind transects of plumes from the city and nearby point sources, such as power plants, paper mills and landfills, were flown. The area around Atlanta has large biogenic isoprene emissions, which provided an excellent case for studying the interactions between biogenic and anthropogenic emissions. In this example flight, chemistry in and outside the Atlanta plumes was observed for several hours after emission. The analysis of this flight showcases the strategies implemented to answer some of the main SENEX science questions.
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Oh KS, Lee JH, Yi KY, Lim CJ, Lee S, Park CH, Seo HW, Lee BH. The orally active urotensin receptor antagonist, KR36676, attenuates cellular and cardiac hypertrophy. Br J Pharmacol 2015; 172:2618-33. [PMID: 25597918 DOI: 10.1111/bph.13082] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 12/11/2014] [Accepted: 01/13/2015] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND AND PURPOSE Blockade of the actions of urotensin-II (U-II) mediated by the urotensin (UT) receptor should improve cardiac function and prevent cardiac remodelling in cardiovascular disease. Here, we have evaluated the pharmacological properties of the recently identified UT receptor antagonist, 2-(6,7-dichloro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl)-N-methyl-N-(2-(pyrrolidin-1-yl)-1-(4-(thiophen-3-yl)phenyl) ethyl)acetamide (KR36676). EXPERIMENTAL APPROACH Pharmacological properties of KR36676 were studied in a range of in vitro assays (receptor binding, calcium mobilization, stress fibre formation, cellular hypertrophy) and in vivo animal models such as cardiac hypertrophy induced by transverse aortic constriction (TAC) or myocardial infarction (MI). KEY RESULTS KR36676 displayed high binding affinity for the UT receptor (Ki : 0.7 nM), similar to that of U-II (0.4 nM), and was a potent antagonist at that receptor (IC50 : 4.0 nM). U-II-induced stress fibre formation and cellular hypertrophy were significantly inhibited with low concentrations of KR36676 (≥0.01 μM). Oral administration of KR36676 (30 mg·kg(-1) ) in a TAC model in mice attenuated cardiac hypertrophy and myocardial fibrosis. Moreover, KR36676 restored cardiac function and myocyte size in rats with MI-induced cardiac hypertrophy. CONCLUSIONS AND IMPLICATIONS A highly potent UT receptor antagonist exerted anti-hypertrophic effects not only in infarcted rat hearts but also in pressure-overloaded mouse hearts. KR36676 could be a valuable pharmacological tool in elucidating the complicated physiological role of U-II and UT receptors in cardiac hypertrophy.
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Halder D, Mandal C, Lee BH, Lee JS, Choi MR, Chai JC, Lee YS, Jung KH, Chai YG. PCDHB14- and GABRB1-like nervous system developmental genes are altered during early neuronal differentiation of NCCIT cells treated with ethanol. Hum Exp Toxicol 2015; 34:1017-27. [PMID: 25566775 DOI: 10.1177/0960327114566827] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Ethanol (EtOH) exposure during embryonic development causes dysfunction of the central nervous system (CNS). Here, we examined the effects of chronic EtOH on gene expression during early stages of neuronal differentiation. Human embryonic carcinoma (NCCIT) cells were differentiated into neuronal precursors/lineages in the presence or absence of EtOH and folic acid. Gene expression profiling and pathway analysis demonstrated that EtOH deregulates many genes and pathways that are involved in early brain development. EtOH exposure downregulated several important genes, such as PCDHB14, GABRB1, CTNND2, NAV3, RALDH1, and OPN5, which are involved in CNS development, synapse assembly, synaptic transmission, and neurotransmitter receptor activity. GeneGo pathway analysis revealed that the deregulated genes mapped to disease pathways that were relevant to fetal alcohol spectrum disorders (FASD, such as neurotic disorders, epilepsy, and alcohol-related disorders). In conclusion, these findings suggest that the impairment of the neurological system or suboptimal synapse formation resulting from EtOH exposure could underlie the neurodevelopmental disorders in individuals with FASD.
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Goh CH, Lee BH, Lahiri A. Biphasic motion of the median nerve in the normal Asian population. HAND SURGERY : AN INTERNATIONAL JOURNAL DEVOTED TO HAND AND UPPER LIMB SURGERY AND RELATED RESEARCH : JOURNAL OF THE ASIA-PACIFIC FEDERATION OF SOCIETIES FOR SURGERY OF THE HAND 2015; 20:73-80. [PMID: 25609278 DOI: 10.1142/s0218810415500100] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
BACKGROUND The biomechanical interaction between the median nerve and the flexor tendons is an important consideration in Carpal tunnel syndrome (CTS). We aim to quantify the displacement and compressive deformation pattern of the median nerve in various stages of finger flexion in the normal population at the inlet of the carpal tunnel. METHODS Transverse ultrasounds images were taken at the carpal tunnel inlet during full-extension, mid-flexion and full flexion. The displacement, distance, Feret's diameter, and perimeter of the median nerve were calculated and compared between each position. RESULTS Biphasic median nerve motion was observed, with a displacement of 2.84 ± 3.49 mm in the ulnar direction from full-extension to mid-flexion (Phase I) and a further 0.93 ± 3.04 mm from mid-flexion to full flexion (Phase II). Of 49 hands, 37 (75.5%) exhibited ulnar displacement in Phase I while 12 (24.5%) exhibited radial displacement. Feret's diameter (5.95 ± 1.08 mm) and perimeter (13.28 ± 2.09) of the median nerve were greatest in the mid-flexed position. CONCLUSION In a healthy Asian population, the median nerve has a biphasic motion during finger flexion, with maximal deformation in the mid-flexed position.
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Nejad JG, Hosseindoust A, Shoae A, Ghorbani B, Lee BH, Oskoueian E, Hajilari D, Amouzmehr A, Lohakare JD, Sung KI. Effects of feeding levels of starter on weaning age, performance, nutrient digestibility and health parameters in holstein dairy calves. ASIAN-AUSTRALASIAN JOURNAL OF ANIMAL SCIENCES 2014; 26:827-30. [PMID: 25049856 PMCID: PMC4093240 DOI: 10.5713/ajas.2012.12704] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/19/2012] [Revised: 03/15/2013] [Accepted: 02/24/2013] [Indexed: 11/27/2022]
Abstract
To evaluate the effects of feeding four different levels of starter in male Holstein dairy calves, a completely randomized study was conducted, using 28 calves with initial body weight of 40.5±2.4 kg. The animals were fed iso-nitrogenous starter and were weaned when they consumed 350, 500, 650 and 800 g/d of starter for 3 d consecutively. Starter and water were available ad-libitum throughout the experiment. Body weight at pre-weaning (less than 5 wk) and post-weaning (8 wk) was lower in calves that received 350 g/d of starter than in the other treatments (p<0.05). Feed conversion ratio (FCR) was the highest among all treatments in pre-weaning period (p<0.05). Dry matter intake (DMI) at weaning and total DMI was higher in that calves received 800 g/d of starter compared with other treatments (p<0.05). Calves fed 350 and 500 g/d of starter were weaned earlier (p<0.05) and showed lower milk consumption (kg, DM) compared with other treatments whereas no significant difference was observed between calves fed 350 and 500 g/d of starter (p>0.05). Dry matter, organic matter and crude protein digestibilities were lower in calves that received 350 g/d of starter compared with other treatments (p<0.05). No differences were observed in acid detergent and neutral detergent fiber digestibility among all treatments (p>0.05).Treatments had no significant effect on time of starting rumination, respiratory score, and days of drug administration for pneumonia. There were no meaningful differences in feces, fecal odor scores, body temperature, and days of drug administration for diarrhea among all treatments (p>0.05). Total dry matter intake at the end of experiment showed no significant difference among calves fed 600 and 800 g/d of starter, but calves fed 350 and 500 g/d of starter showed more dry matter (DM) intake than calves in the 600 and 800 g/d groups (p<0.05).
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Patel RM, Nagamani SCS, Cuthbertson D, Campeau PM, Krischer JP, Shapiro JR, Steiner RD, Smith PA, Bober MB, Byers PH, Pepin M, Durigova M, Glorieux FH, Rauch F, Lee BH, Hart T, Sutton VR. A cross-sectional multicenter study of osteogenesis imperfecta in North America - results from the linked clinical research centers. Clin Genet 2014; 87:133-40. [PMID: 24754836 DOI: 10.1111/cge.12409] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 04/08/2014] [Accepted: 04/19/2014] [Indexed: 02/06/2023]
Abstract
Osteogenesis imperfecta (OI) is the most common skeletal dysplasia that predisposes to recurrent fractures and bone deformities. In spite of significant advances in understanding the genetic basis of OI, there have been no large-scale natural history studies. To better understand the natural history and improve the care of patients, a network of Linked Clinical Research Centers (LCRC) was established. Subjects with OI were enrolled in a longitudinal study, and in this report, we present cross-sectional data on the largest cohort of OI subjects (n = 544). OI type III subjects had higher prevalence of dentinogenesis imperfecta, severe scoliosis, and long bone deformities as compared to those with OI types I and IV. Whereas the mean lumbar spine area bone mineral density (LS aBMD) was low across all OI subtypes, those with more severe forms had lower bone mass. Molecular testing may help predict the subtype in type I collagen-related OI. Analysis of such well-collected and unbiased data in OI can not only help answering questions that are relevant to patient care but also foster hypothesis-driven research, especially in the context of 'phenotypic expansion' driven by next-generation sequencing.
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Rosen MA, Sampson JB, Jackson EV, Koka R, Chima AM, Ogbuagu OU, Marx MK, Koroma M, Lee BH. Failure mode and effects analysis of the universal anaesthesia machine in two tertiary care hospitals in Sierra Leone. Br J Anaesth 2014; 113:410-5. [PMID: 24833727 PMCID: PMC4136424 DOI: 10.1093/bja/aeu096] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background Anaesthesia care in developed countries involves sophisticated technology and experienced providers. However, advanced machines may be inoperable or fail frequently when placed into the austere medical environment of a developing country. Failure mode and effects analysis (FMEA) is a method for engaging local staff in identifying real or potential breakdowns in processes or work systems and to develop strategies to mitigate risks. Methods Nurse anaesthetists from the two tertiary care hospitals in Freetown, Sierra Leone, participated in three sessions moderated by a human factors specialist and an anaesthesiologist. Sessions were audio recorded, and group discussion graphically mapped by the session facilitator for analysis and commentary. These sessions sought to identify potential barriers to implementing an anaesthesia machine designed for austere medical environments—the universal anaesthesia machine (UAM)—and also engaging local nurse anaesthetists in identifying potential solutions to these barriers. Results Participating Sierra Leonean clinicians identified five main categories of failure modes (resource availability, environmental issues, staff knowledge and attitudes, and workload and staffing issues) and four categories of mitigation strategies (resource management plans, engaging and educating stakeholders, peer support for new machine use, and collectively advocating for needed resources). Conclusions We identified factors that may limit the impact of a UAM and devised likely effective strategies for mitigating those risks.
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Cho SY, Yoon YA, Ki CS, Huh HJ, Yoo HW, Lee BH, Kim GH, Yoo JH, Kim SY, Kim SJ, Sohn YB, Park SW, Huh R, Chang MS, Lee J, Kwun Y, Maeng SH, Jin DK. Clinical characterization and molecular classification of 12 Korean patients with pseudohypoparathyroidism and pseudopseudohypoparathyroidism. Exp Clin Endocrinol Diabetes 2013; 121:539-45. [PMID: 24127307 DOI: 10.1055/s-0033-1349867] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
CONTEXT Pseudohypoparathyroidism (PHP) is defined as resistance toward parathyroid hormones. PHP and pseudopseudohypoparathyroidism (PPHP) are rare disorders resulting from genetic and epigenetic aberrations within or upstream of the GNAS locus. This study investigated the clinical characteristics and performed a molecular analysis of PHP and PPHP. METHODS A total of 12 patients with (P)PHP from 11 unrelated families (4 with PHP-Ia, 6 with PHP-Ib, and 2 with PPHP) were characterized using both clinical and molecular methods. Clinical features included the presenting symptoms, Albright hereditary osteodystrophy features, and resistance to hormones. Comprehensive analysis of the GNAS and STX16 loci was undertaken to investigate the molecular defects underlying (P)PHP. RESULTS All PHP-Ib patients displayed hypocalcemic symptoms. All PHP-Ia patients showed resistance toward TSH, in addition to PTH. In most patients with PHP, when the diagnosis of PHP was first established, hypocalcemia and hyperphosphatemia were associated with a significant increase in serum PTH levels. One patient with PHP-Ia was diagnosed with growth hormone deficiency and showed a good response to human recombinant growth hormone therapy. 6 patients with PHP-Ia and PPHP showed 5 different mutations in the GNAS gene. 5 patients with PHP-Ib displayed a loss of differentially methylated region (DMR) imprints of the maternal GNAS. One PHP-Ib patient showed a de novo microdeletion in STX16 and a loss of methylation of exon A/B on the maternal allele. No patients revealed paternal disomy among 4 patients with PHP-Ib. CONCLUSIONS Identification of the molecular causes of PHP and PPHP explains their distinctive clinical features and enables confirmation of the diagnosis and exact genetic counseling.
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Kim MT, Rhee KY, Lee BH, Kim CJ. Effect of carbon nanotube addition on the wear behavior of basalt/epoxy woven composites. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2013; 13:5631-5635. [PMID: 23882807 DOI: 10.1166/jnn.2013.7037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The effect of acid-treated carbon nanotube (CNT) addition on the wear and dynamic mechanical thermal properties of basalt/epoxy woven composites was investigated in this study. Basalt/CNT/epoxy composites were fabricated by impregnating woven basalt fibers into epoxy resin mixed with 1 wt% CNTs which were acid-treated. Wear and DMA (dynamic mechanical analyzer) tests were performed on basalt/epoxy composites and basalt/CNT/epoxy composites. The results showed that the addition of the acid-treated CNTs improved the wear properties of basalt/epoxy woven composites. Specifically, the friction coefficient of the basalt/epoxy composite was stabilized in the range of 0.5-0.6 while it fell in the range of 0.3-0.4 for basalt/CNT/epoxy composites. The wear volume loss of the basalt/CNT/epoxy composites was approximately 68% lower than that of the basalt/epoxy composites. The results also showed that the glass transition temperature of basalt/CNT/epoxy composites was higher than that of basalt/epoxy composites. The improvement of wear properties of basalt/epoxy composites by the addition of acid-treated CNTs was caused by the homogeneous load transfer between basalt fibers and epoxy matrix due to the reinforcement of CNTs.
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Sule G, Campeau PM, Zhang VW, Nagamani SCS, Dawson BC, Grover M, Bacino CA, Sutton VR, Brunetti-Pierri N, Lu JT, Lemire E, Gibbs RA, Cohn DH, Cui H, Wong LJ, Lee BH. Next-generation sequencing for disorders of low and high bone mineral density. Osteoporos Int 2013; 24:2253-9. [PMID: 23443412 PMCID: PMC3709009 DOI: 10.1007/s00198-013-2290-0] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 01/03/2013] [Indexed: 10/27/2022]
Abstract
UNLABELLED To achieve an efficient molecular diagnosis of osteogenesis imperfecta (OI), Ehlers-Danlos syndrome (EDS), and osteopetrosis (OPT), we designed a next-generation sequencing (NGS) platform to sequence 34 genes. We validated this platform on known cases and have successfully identified the causative mutation in most patients without a prior molecular diagnosis. INTRODUCTION Osteogenesis imperfecta, Ehlers-Danlos syndrome, and osteopetrosis are collectively common inherited skeletal diseases. Evaluation of subjects with these conditions often includes molecular testing which has important counseling and therapeutic and sometimes legal implications. Since several different genes have been implicated in these conditions, Sanger sequencing of each gene can be a prohibitively expensive and time-consuming way to reach a molecular diagnosis. METHODS In order to circumvent these problems, we have designed and tested a NGS platform that would allow simultaneous sequencing on a single diagnostic platform of different genes implicated in OI, OPT, EDS, and other inherited conditions, leading to low or high bone mineral density. We used a liquid-phase probe library that captures 602 exons (~100 kb) of 34 selected genes and have applied it to test clinical samples from patients with bone disorders. RESULTS NGS of the captured exons by Illumina HiSeq 2000 resulted in an average coverage of over 900X. The platform was successfully validated by identifying mutations in six patients with known mutations. Moreover, in four patients with OI or OPT without a prior molecular diagnosis, the assay was able to detect the causative mutations. CONCLUSIONS In conclusion, our NGS panel provides a fast and accurate method to arrive at a molecular diagnosis in most patients with inherited high or low bone mineral density disorders.
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