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1.
Exp Mol Med ; 56(3): 721-733, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38528124

RESUMEN

Acetyl-CoA synthetase 2 (ACSS2)-dependent acetate usage has generally been associated with tumorigenesis and increased malignancy in cancers under nutrient-depleted conditions. However, the nutrient usage and metabolic characteristics of the liver differ from those of other organs; therefore, the mechanism of ACSS2-mediated acetate metabolism may also differ in liver cancer. To elucidate the underlying mechanisms of ACSS2 in liver cancer and acetate metabolism, the relationships between patient acetate uptake and metabolic characteristics and between ACSS2 and tumor malignancies were comprehensively studied in vitro, in vivo and in humans. Clinically, we initially found that ACSS2 expression was decreased in liver cancer patients. Moreover, PET-CT imaging confirmed that lower-grade cancer cells take up more 11C-acetate but less 18F-fluorodeoxyglucose (18F-FDG); however, this trend was reversed in higher-grade cancer. Among liver cancer cells, those with high ACSS2 expression avidly absorbed acetate even in a glucose-sufficient environment, whereas those with low ACSS2 expression did not, thereby showing correlations with their respective ACSS2 expression. Metabolomic isotope tracing in vitro and in vivo revealed greater acetate incorporation, greater lipid anabolic metabolism, and less malignancy in high-ACSS2 tumors. Notably, ACSS2 downregulation in liver cancer cells was associated with increased tumor occurrence in vivo. In human patient cohorts, patients in the low-ACSS2 subgroup exhibited reduced anabolism, increased glycolysis/hypoxia, and poorer prognosis. We demonstrated that acetate uptake by ACSS2 in liver cancer is independent of glucose depletion and contributes to lipid anabolic metabolism and reduced malignancy, thereby leading to a better prognosis for liver cancer patients.


Asunto(s)
Glucosa , Neoplasias Hepáticas , Humanos , Acetilcoenzima A/metabolismo , Glucosa/metabolismo , Tomografía Computarizada por Tomografía de Emisión de Positrones , Línea Celular Tumoral , Acetatos , Ligasas
2.
Cancer Lett ; 588: 216781, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38494150

RESUMEN

Metastatic lung adenocarcinoma (LuAC) presents a significant clinical challenge due to the short latency and the lack of efficient treatment options. Therefore, identification of molecular vulnerabilities in metastatic LuAC holds great importance in the development of therapeutic drugs against this disease. In this study, we performed a genome-wide siRNA screening using poorly and highly brain-metastatic LuAC cell lines. Using this approach, we discovered that compared to poorly metastatic LuAC (LuAC-Par) cells, brain-metastatic LuAC (LuAC-BrM) cells exhibited a significantly higher vulnerability to c-FLIP (an inhibitor of caspase-8)-depletion-induced apoptosis. Furthermore, in vivo studies demonstrated that c-FLIP knockdown specifically inhibited growth of LuAC-BrM, but not the LuAC-Par, tumors, suggesting the addiction of LuAC-BrM to the function of c-FLIP for their survival. Our in vitro and in vivo analyses also demonstrated that LuAC-BrM is more sensitive to c-FLIP-depletion due to ER stress-induced activation of the c-JUN and subsequent induction of stress genes including ATF4 and DDIT3. Finally, we found that c-JUN not only sensitized LuAC-BrM to c-FLIP-depletion-induced cell death but also promoted brain metastasis in vivo, providing strong evidence for c-JUN's function as a double-edged sword in LuAC-BrM. Collectively, our findings not only reveal a novel link between c-JUN, brain metastasis, and c-FLIP addiction in LuAC-BrM but also present an opportunity for potential therapeutic intervention.


Asunto(s)
Adenocarcinoma del Pulmón , Neoplasias Encefálicas , Neoplasias Pulmonares , Humanos , Adenocarcinoma del Pulmón/genética , Adenocarcinoma del Pulmón/patología , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Neoplasias Pulmonares/metabolismo , Encéfalo/patología , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Proteína Reguladora de Apoptosis Similar a CASP8 y FADD
3.
Biomol Ther (Seoul) ; 31(6): 599-610, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37183002

RESUMEN

According to recent evidence, ferroptosis is a major cell death mechanism in the pathogenesis of kidney injury and fibrosis. Despite the renoprotective effects of classical ferroptosis inhibitors, therapeutic approaches targeting kidney ferroptosis remain limited. In this study, we assessed the renoprotective effects of melatonin and zileuton as a novel therapeutic strategy against ferroptosis-mediated kidney injury and fibrosis. First, we identified RSL3-induced ferroptosis in renal tubular epithelial HK-2 and HKC-8 cells. Lipid peroxidation and cell death induced by RSL3 were synergistically mitigated by the combination of melatonin and zileuton. Combination treatment significantly downregulated the expression of ferroptosis-associated proteins, 4-HNE and HO-1, and upregulated the expression of GPX4. The expression levels of p-AKT and p-mTOR also increased, in addition to that of NRF2 in renal tubular epithelial cells. When melatonin (20 mg/kg) and zileuton (20 mg/kg) were administered to a unilateral ureteral obstruction (UUO) mouse model, the combination significantly reduced tubular injury and fibrosis by decreasing the expression of profibrotic markers, such as α-SMA and fibronectin. More importantly, the combination ameliorated the increase in 4-HNE levels and decreased GPX4 expression in UUO mice. Overall, the combination of melatonin and zileuton was found to effectively ameliorate ferroptosis-related kidney injury by upregulating the AKT/mTOR/ NRF2 signaling pathway, suggesting a promising therapeutic strategy for protection against ferroptosis-mediated kidney injury and fibrosis.

4.
Biomed Pharmacother ; 162: 114716, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37086509

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) exhibits a pronounced extracellular matrix (ECM)-rich response, which is produced by an excessive amount of transforming growth factor ß (TGF-ß), resulting in tumor progression and metastasis. In addition, TGF-ß signaling contributes to rapidly acquired resistance and incomplete response to gemcitabine. Recently, selective inhibitors of the TGF-ß signaling pathway have shown promise in PDAC treatment, particularly as an option for augmenting responses to chemotherapy. Here, we investigated the synergistic anticancer effects of a small-molecule TGF-ß receptor I kinase inhibitor (vactosertib/EW-7197) in the presence of gemcitabine, and its mechanism of action in pancreatic cancer. Vactosertib sensitized pancreatic cancer cells to gemcitabine by synergistically inhibiting their viability. Importantly, the combination of vactosertib and gemcitabine significantly attenuated the expression of major ECM components, including collagens, fibronectin, and α-SMA, in pancreatic cancer compared with gemcitabine alone. This resulted in potent induction of mitochondrial-mediated apoptosis, gemcitabine-mediated cytotoxicity, and inhibition of tumor ECM by vactosertib. Additionally, the combination decreased metastasis through inhibition of migration and invasion, and exhibited synergistic anti-cancer activity by inhibiting the TGF-ß/Smad2 pathway in pancreatic cancer cells. Furthermore, co-treatment significantly suppressed tumor growth in orthotopic models. Therefore, our findings demonstrate that vactosertib synergistically increased the antitumor activity of gemcitabine via inhibition of ECM component production by inhibiting the TGF-ß/Smad2 signaling pathway. This suggests that the combination of vactosertib and gemcitabine may be a potential treatment option for patients with pancreatic cancer.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Gemcitabina , Desoxicitidina/farmacología , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/patología , Factor de Crecimiento Transformador beta/metabolismo , Línea Celular Tumoral , Neoplasias Pancreáticas
5.
Nanomaterials (Basel) ; 13(4)2023 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-36838990

RESUMEN

Ca1-xLaxFeAs2 (CLFA112) belongs to a new family of Fe-based superconductors (FeSCs) and has a unique crystal structure featuring an arsenic zigzag chain layer, which has been proposed to be a possible two-dimensional topological insulator. This suggests that CLFA112 is a potential topological superconductor-a platform to realize Majorana fermions. Up to now, even a clear superconducting (SC) gap in CLFA112 has never been observed, and the SC properties of CLFA112 remain largely elusive. In this letter, we report the results of an atomic-scale investigation of the electronic structure of CLFA112 crystals using low-temperature scanning tunneling microscopy (STM). We revealed four different types of surfaces exhibiting distinct electronic properties, with all surfaces displaying dominating 2 × 1 surface reconstructions. On a Ca/La layer on top of an FeAs layer, a clear SC gap of ~12 mV was observed only at the crevices (vacancies) where the FeAs layer can be directly accessed. Remarkably, the FeAs termination layer displayed a dispersing nematic modulation both in real and q space. We also present peculiar zero-bias conductance peaks for the very As chain layer that is believed to exhibit a topological edge state as well as the influence of La dopants on the As chain layer.

6.
Am J Cancer Res ; 12(9): 4326-4342, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36225647

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is an extracellular matrix (ECM)-rich carcinoma, which promotes chemoresistance by inhibiting drug diffusion into the tumor. Discoidin domain receptor 1 (DDR1) increases tumor progression and drug resistance by binding to collagen, a major component of tumor ECM. Therefore, DDR1 inhibition may be helpful in cancer therapeutics by increasing drug delivery efficiency and improving drug sensitivity. In this study, we developed a novel DDR1 inhibitor, KI-301690 and investigated whether it could improve the anticancer activity of gemcitabine, a cytotoxic agent widely used for the treatment of pancreatic cancer. KI-301690 synergized with gemcitabine to suppress the growth of pancreatic cancer cells. Importantly, its combination significantly attenuated the expression of major tumor ECM components including collagen, fibronectin, and vimentin compared to gemcitabine alone. Additionally, this combination effectively decreased mitochondrial membrane potential (MMP), thereby inducing apoptosis. Further, the combination synergistically inhibited cell migration and invasion. The enhanced anticancer efficacy of the co-treatment could be explained by the inhibition of DDR1/PYK2/FAK signaling, which significantly reduced tumor growth in a pancreatic xenograft model. Our results demonstrate that KI-301690 can inhibit aberrant ECM expression by DDR1/PYK2/FAK signaling pathway blockade and attenuation of ECM-induced chemoresistance observed in desmoplastic pancreatic tumors, resulting in enhanced antitumor effect through effective induction of gemcitabine apoptosis.

7.
Am J Cancer Res ; 12(7): 3083-3098, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35968350

RESUMEN

The use of anesthetics in the surgical resection of tumors may influence the prognosis of cancer patients. Lidocaine, a local anesthetic, is known to act as a chemosensitizer and relieve pain in some cancers. In addition, palbociclib, a potent cyclin-dependent kinase (CDK) 4/6 inhibitor, has been approved for chemotherapy of advanced breast cancer. However, recent studies have revealed the acquired resistance of breast cancer cells to palbociclib. Therefore, the development of combination therapies that can extend the efficacy of palbociclib or delay resistance is crucial. This study investigated whether lidocaine would enhance the efficacy of palbociclib in breast cancer. Lidocaine synergistically suppressed the growth and proliferation of breast cancer cells by palbociclib. The combination treatment showed an increased cell cycle arrest in the G0/G1 phase by decreasing retinoblastoma protein (Rb) and E2F1 expression. In addition, it increased apoptosis by loss of mitochondrial membrane potential as observed by increases in cytochrome c release and inhibition of mitochondria-mediated protein expression. Additionally, it significantly reduced epithelial-mesenchymal transition and PI3K/AKT/GSK3ß signaling. In orthotopic breast cancer models, this combination treatment significantly inhibited tumor growth and increased tumor cell apoptosis compared to those treated with a single drug. Taken together, this study demonstrates that the combination of palbociclib and lidocaine has a synergistic anti-cancer effect on breast cancer cells by the inhibition of the PI3K/AKT/GSK3ß pathway, suggesting that this combination could potentially be an effective therapy for breast cancer.

8.
J Natl Cancer Inst ; 114(2): 228-234, 2022 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-34613397

RESUMEN

BACKGROUND: Pancreatic cancer (PC) has a grim prognosis, and an early diagnostic biomarker has been highly desired. The molecular link between diabetes and PC has not been well established. METHODS: Bioinformatics screening was performed for a serum PC marker. Experiments in cell lines (5 PC and 1 normal cell lines), mouse models, and human tissue staining (37 PC and 10 normal cases) were performed to test asprosin production from PC. Asprosin's diagnostic performance was tested with serums from multi-center cohorts (347 PC, 209 normal, and 55 additional diabetic patients) and evaluated according to PC status, stages, and diabetic status, which was compared with that of CA19-9. RESULTS: Asprosin, a diabetes-related hormone, was found from the bioinformatics screening, and its production from PC was confirmed. Serum asprosin levels from multi-center cohorts yielded an age-adjusted diagnostic area under the curve (AUC) of 0.987 (95% confidence interval [CI] = 0.961 to 0.997), superior to that of CA19-9 (AUC = 0.876, 95% CI = 0.847 to 0.905), and a cut-off of 7.18 ng/mL, at which the validation set exhibited a sensitivity of 0.957 and a specificity of 0.924. Importantly, the performance was maintained in early-stage and non-metastatic PC, consistent with the tissue staining. A slightly lower performance against additional diabetic patients (n = 55) was restored by combining asprosin and CA19-9 (AUC = 0.985, 95% CI = 0.975 to 0.995). CONCLUSIONS: Asprosin is presented as an early-stage PC serum marker that may provide clues for PC-induced diabetes. Larger prospective clinical studies are warranted to solidify its utility.


Asunto(s)
Diabetes Mellitus , Neoplasias Pancreáticas , Animales , Biomarcadores de Tumor , Antígeno CA-19-9 , Humanos , Ratones , Neoplasias Pancreáticas/patología , Estudios Prospectivos
9.
Materials (Basel) ; 16(1)2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36614374

RESUMEN

We propose a deformable photonic crystal that exhibits the thermal-mediative shape memory effect. The chiral liquid crystalline polymeric scaffold, which produces the structural colors from a helical twist of the liquid crystal director, is prepared through phase-stabilization of a reactive mesogen in a small molecular chiral liquid crystal (CLC), polymerization, and removal of the CLC. The prepolymer of polyurethane acrylate (PUA) is then infiltrated in the prepared scaffold and subsequently photo-polymerized to form a CLC-PUA composite film. Upon compression, this film shows the blue shift of the structural color and retains this color-shift as released from compression. As the temperature increases, the color is recovered to a pristine state. The concept proposed in this study will be useful for designing mechanochromic soft materials.

10.
Cancer Lett ; 521: 294-307, 2021 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-34416337

RESUMEN

The deregulation of polypeptide N-acetyl-galactosaminyltransferases (GALNTs) contributes to several cancers, but their roles in lung cancer remain unclear. In this study, we have identified a tumor-suppressing role of GALNT3 in lung cancer. We found that GALNT3 suppressed lung cancer development and progression in both xenograft and syngeneic mouse models. Specifically, GALNT3 suppressed lung cancer initiation by inhibiting the self-renewal of lung cancer cells. More importantly, GALNT3 attenuated lung cancer growth by preventing the creation of a favorable tumor microenvironment (TME), which was attributed to GALNT3's ability to inhibit myeloid-derived suppressor cell (MDSC) infiltration into tumor sites and subsequent angiogenesis. We also identified a GALNT3-regulated gene (GRG) signature and found that lung cancer patients whose tumors exhibit the GRG signature showed more favorable prognoses. Further investigation revealed that GALNT3 suppressed lung cancer cell self-renewal by reducing ß-catenin levels, which led to reduced expression of the downstream targets of the WNT pathway. In addition, GALNT3 inhibited MDSC infiltration into tumor sites by suppressing both the TNFR1-NFκB and cMET-pAKT pathways. Specifically, GALNT3 inhibited the nuclear localization of NFκB and the c-MET-induced phosphorylation of AKT. This then led to reduced production of CXCL1, a chemokine required for MDSC recruitment. Finally, we confirmed that the GALNT3-induced inhibition of the TNFR1-NFκB and cMET-pAKT pathways involved the O-GalNAcylation of the TNFR1 and cMET receptors. In summary, we have identified GALNT3 as the first GALNT member capable of suppressing lung cancer and uncovered a novel mechanism by which GALNT3 regulates the TME.

11.
FEBS J ; 288(9): 2888-2910, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33205541

RESUMEN

Poly (ADP-ribose) polymerase 1 (PARP1) and polycomb-repressive complex 2 (PRC2) are each known for their individual roles in cancer, but their cooperative roles have only been studied in the DNA damage repair process in the context of BRCA-mutant cancers. Here, we show that simultaneous inhibition of PARP1 and PRC2 in the MDA-MB-231 BRCA-proficient triple-negative breast cancer (TNBC) cell line leads to a synthetic viability independent of the mechanisms of DNA damage repair. Specifically, we find that either genetic depletion or pharmacological inhibition of both PARP1 and PRC2 can accelerate tumor growth rate. We attribute this to modifications in the tumor microenvironment (TME) that are induced by double-depleted breast cancer cells, such as promoting intratumoral angiogenesis and increasing the proportion of tumor-promoting type 2 (M2) macrophages. These changes subsequently inhibit cell death and promote proliferation. Mechanistically, we find that PARP1 and PRC2 double depletion induces not only a basal activation of the NF-κB pathway but also a maximal activation of NF-κB within the TME in response to external stimuli such as hypoxia and the presence of macrophages. In summary, our study reveals an unprecedented synthetic viable interaction between PARP1 and PRC2 in BRCA-proficient TNBC and identifies NF-κB as the downstream mediator. DATABASE: RNA-seq data are available in the GEO databases under the accession GSE142769.


Asunto(s)
Proteína Potenciadora del Homólogo Zeste 2/genética , Poli(ADP-Ribosa) Polimerasa-1/genética , Complejo Represivo Polycomb 2/genética , Neoplasias de la Mama Triple Negativas/genética , Animales , Proteína BRCA1/genética , Línea Celular Tumoral , Proliferación Celular/genética , Daño del ADN/genética , Reparación del ADN/genética , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Ratones , Neoplasias de la Mama Triple Negativas/patología , Microambiente Tumoral/genética , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Oncol Rep ; 34(5): 2602-8, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26323587

RESUMEN

The present study is the first to demonstrate the anticancer effects of a hexane extract from the brown algae Sargassum serratifolium (HES) on human cancer cell lines, including glioblastoma U87MG, cervical cancer HeLa and gastric cancer MKN-28 cells, as well as liver cancer SK-HEP 1 cells. Among these cancer cell lines, U87MG cells were most sensitive to the cell death induced by HES. HES exhibited a cytotoxic effect on U87MG cells at concentrations of 14-16 µg/ml, yet an effect was not observed in human embryonic kidney HEK293 cells. The antiproliferative effects of HES were regulated by inhibition of the MAPK/ERK signaling pathway which plays a pivotal role in the proliferation of glioblastoma U87MG cells. In addition, treatment with HES led to cell morphological changes and cell cytoskeleton degradation through regulation of actin dynamic signaling. Furthermore, migration and invasion of the U87MG cells were inhibited by HES via suppression of matrix metalloproteinase (MMP)-2 and -9 expression. Thus, our results suggest that HES is a potential therapeutic agent which has anticancer effects on glioblastoma.


Asunto(s)
Antineoplásicos/farmacología , Glioblastoma/metabolismo , Hexanos/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Sargassum/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Citoesqueleto/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma/tratamiento farmacológico , Células HEK293 , Células HeLa , Humanos , Metástasis de la Neoplasia/tratamiento farmacológico
13.
Drug Dev Res ; 76(3): 132-42, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25959042

RESUMEN

Hepatocellular carcinoma (HCC) is one of the most malignant and frequent cancers with a high metastatic potential. The prevention of HCC metastasis is a critical target for effective therapies in HCC. Gambogic acid (GA), a natural compound obtained from Garcinia hanburyi has reported anticancer activity in cell lines. However, the antimetastatic mechanisms of GA are unclear, particularly with respect to HCC. In this study, the influence of GA on migration and invasion of SK-HEP1 cells was evaluated. At concentrations above 0.6 µM, GA reduced cell proliferation in SK-HEP1 cells without affecting proliferation of noncancerous HEK-293 cells. GA also suppressed migration and invasion of SK-HEP1 cells. GA downregulated the expression of the integrin ß1/rho family GTPase signaling pathway, suppressed the actin rearrangement related to cell cytoskeleton and migration and decreased matrix metalloproteinases MMP-2, MMP-9, and NF-κB expression involved in cancer invasion. These results suggest that GA may be a potential lead in developing an antimetastatic therapeutic for the treatment of HCC.


Asunto(s)
Citoesqueleto de Actina/metabolismo , Antineoplásicos/farmacología , FN-kappa B/metabolismo , Xantonas/farmacología , Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Movimiento Celular/efectos de los fármacos , Movimiento Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Relación Dosis-Respuesta a Droga , Células HEK293 , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , FN-kappa B/antagonistas & inhibidores , Invasividad Neoplásica/patología , Xantonas/uso terapéutico
14.
J Craniofac Surg ; 23(5): e497-9, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22976720

RESUMEN

Subperiosteal orbital hematoma occurs rarely after blunt trauma. However, this is of importance, as this condition may cause ocular symptoms. The major characteristics of subperiosteal orbital hematomas are painful proptosis, downward displacement of the globe, absence of lid ecchymosis, chemosis without subconjunctival hemorrhage, and motility impairment. Visual impairment is known as a rarely presenting symptom. A 22-year-old male patient presented with right periorbital ecchymosis, swelling, and diplopia with upper lateral gaze limitation. Besides, the patient complained of lower visual field disturbance. Radiologic evaluation revealed traumatic subperiosteal orbital hematoma. The hematoma was evacuated through a lacerated wound on the right lateral eyebrow with additional incision. After the hematoma evacuation, the orbital symptoms are restored. Postoperative computed tomographic scans showed normally restored orbital space without any evidence of remnant hematoma or rebleeding. In case of subperiosteal hematoma, early detection and complete surgical evacuation is crucial for preventing possible complications and sequelae.


Asunto(s)
Enfermedades Orbitales/cirugía , Fracturas Craneales/cirugía , Heridas no Penetrantes/cirugía , Accidentes por Caídas , Diplopía/cirugía , Hueso Frontal/diagnóstico por imagen , Hueso Frontal/lesiones , Hueso Frontal/cirugía , Hematoma , Humanos , Masculino , Enfermedades Orbitales/diagnóstico por imagen , Fracturas Craneales/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Heridas no Penetrantes/diagnóstico por imagen , Adulto Joven
15.
Arch Plast Surg ; 39(3): 204-8, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22783527

RESUMEN

BACKGROUND: Isolated pure blowout fractures are clinically important because they are the main cause of serious complications such as diplopia and limitation of extraocular movement. Many reports have described the incidence of blowout fractures associated with diplopia and limitation of extraocular movement; however, no studies have statistically analyzed this relationship. The purpose of this study was to demonstrate the correlation between the location of isolated pure blowout fractures and orbital symptoms such as diplopia and limitation of extraocular movement. METHODS: We enrolled a total of 354 patients who had been diagnosed with isolated pure blowout fractures, based on computed tomography, from June 2008 to November 2011. Medical records were reviewed, and the prevalence of extraocular movement limitations and diplopia were determined. RESULTS: There were 14 patients with extraocular movement limitation and 58 patients complained of diplopia. Extraocular movement limitation was associated with the following findings, in decreasing order of frequency: floor fracture (7.1%), extended fracture (3.6%), and medial wall (1.7%). However, there was no significant difference among the types of fractures (P=0.60). Diplopia was more commonly associated with floor fractures (21.4%) and extended type fractures (23.6%) than medial wall fractures (10.4%). The difference was statistically significant (Bonferroni-corrected chi-squared test P<0.016). CONCLUSIONS: Data indicate that extended type fractures and orbital floor fractures tend to cause diplopia more commonly than medial wall fractures. However, extraocular movement limitation was not found to be dependent on the location of the orbital wall fracture.

16.
J Microbiol ; 48(1): 111-6, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20221738

RESUMEN

Traditionally primers for PCR detection of viruses have been selected from genomic sequence of single or representative viral strain. However, high mutation rate of viral genomes often results in failure in detecting viruses in clinical and environmental samples. Thus, it seems necessary to consider primers designed from multiple viral sequences in order to improve detection of viral variants. Matchup is a program intended to select universal primers from multiple sequences. We designed using Matchup program primer pairs for HBV detection from 691 full genomic HBV DNA sequences available from NCBI GenBank database. Thousands of primer candidates were initially extracted and these were sequentially filtered down to 5 primer pairs. These primer pairs were tested by PCR using 5 HBV Korean HBsAg(+) patient sera, and eventually one universal primer pair was selected and named MUW (multiple-universal-worldwide). This primer pair, 3 HBV reference primer pairs reported by others and 1 commercial primer pair were compared using 86 HBV HBsAg(+) sera from Korean and Vietnamese patients. The detection rate for MUW primer pair was 72.1%, much greater than those obtained by reference and commercial primers (32.5 to 40.7%). The superiority of MUW primer pair appeared to be correlated with the conserved sequences of the forward primer binding sites and primer quality score. These results suggest that the universal primers designed by the Matchup program from multiple sequences could be useful in detecting viruses from clinical samples.


Asunto(s)
Cartilla de ADN/genética , ADN Viral/genética , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Análisis de Secuencia de ADN/métodos , Secuencia de Bases , ADN Viral/sangre , Bases de Datos Genéticas , Variación Genética , Humanos , Datos de Secuencia Molecular , Mutación , Carga Viral
17.
Sensors (Basel) ; 9(10): 7943-56, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-22408487

RESUMEN

This paper describes the procedures for development of signal analysis algorithms using artificial neural networks for Bridge Weigh-in-Motion (B-WIM) systems. Through the analysis procedure, the extraction of information concerning heavy traffic vehicles such as weight, speed, and number of axles from the time domain strain data of the B-WIM system was attempted. As one of the several possible pattern recognition techniques, an Artificial Neural Network (ANN) was employed since it could effectively include dynamic effects and bridge-vehicle interactions. A number of vehicle traveling experiments with sufficient load cases were executed on two different types of bridges, a simply supported pre-stressed concrete girder bridge and a cable-stayed bridge. Different types of WIM systems such as high-speed WIM or low-speed WIM were also utilized during the experiments for cross-checking and to validate the performance of the developed algorithms.

18.
J Phys Condens Matter ; 19(24): 242201, 2007 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-21694031

RESUMEN

To understand the effect of carbon doping on the superconductivity in MgB(2), we obtained the angle- and temperature-dependent upper critical fields [H(c2)(θ) and H(c2)(T)] for Mg(B(1-x)C(x))(2) single crystals (x = 0.06 and 0.1) from resistivity measurements while varying the temperature, the field, and the direction of the field. The detailed values of the diffusivity for two different directions for each σ-band and π-band were obtained to explain both the temperature- and the angle-dependent H(c2) by using the dirty-limit two-gap model. The induced impurity scattering of the σ-band and the π-band for both the ab-plane and the c-direction is studied.

20.
Solid State Nucl Magn Reson ; 26(3-4): 236-45, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15388188

RESUMEN

Nuclear magnetic resonance (NMR) measurements have been made on two of the electron-doped high-temperature superconducting cuprates (HTSCs), Pr(2-x)Ce(x)CuO(4) and Sr(0.9)La(0.1)CuO(2) that represent the two known electron-doped structures. The results are compared with the more-studied hole-doped HTSCs. We show that the electron and hole-doped HTSCs probe a similar antiferromagnetic spin fluctuation spectrum in the normal state, which provides support for theories of superconductivity where the pairing is mediated by antiferromagnetic spin fluctuations and the superconducting order parameter has a [Formula: see text] symmetry. Contrary to results from underdoped and hole-doped HTSCs, there is no evidence for a normal-state pseudogap in the NMR data from measurements on the electron-doped HTSCs. Therefore, the electron-doped HTSCs can be better compared with overdoped and hole-doped HTSCs where the normal-state pseudogap is absent. The antiferromagnetic spin fluctuation spectrum as probed by the Cu spin-lattice relaxation rate, is independent of the doped electrons per Cu. A similar effect is observed in the overdoped and hole-doped HTSC, Y(1-x)Ca(x)Ba(2)Cu(3)O(7-delta) for a hole concentration range of approximately 0.063. The anomalous Cu NMR linewidth anisotropy observed in the electron-doped HTSCs suggests a small and static spin variation for temperatures up to room temperature.

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