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1.
Eur Radiol ; 30(7): 3803-3812, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32152744

RESUMEN

OBJECTIVE: To compare the diagnostic performance of contrast-enhanced CT with that of MRI in the detection of cartilage invasion in patients with laryngo-hypopharyngeal cancer. METHODS: A systematic literature search in the Ovid-MEDLINE and EMBASE databases was performed for studies reporting diagnostic accuracy of CT and/or MRI in detecting cartilage invasion from laryngo-hypopharyngeal cancer between 2000 and 2018. The pooled sensitivity and specificity, and their 95% confidence intervals were calculated for CT and MRI using bivariate random effects modeling. Subgroup and meta-regression analyses were performed. Indirect comparison was also performed by univariable meta-regression. RESULT: Fourteen articles including 776 patients were included in the systematic review and meta-analysis: eight for CT, and six for MRI. CT and MRI showed pooled sensitivities of 66% (95% CI, 49-80%) and 88% (95% CI, 79-93%), and pooled specificities of 90% (95% CI, 82-94%) and 81% (95% CI, 76-84%), respectively. MRI showed significantly higher sensitivity than CT (p = 0.02). The specificities showed no statistically significant difference between CT and MRI (p = 0.39). The CT studies showed heterogeneity and a threshold effect, while MRI showed neither heterogeneity nor threshold effect. In the meta-regression analysis for CT, the type of cartilage analyzed (thyroid only vs. thyroid/cricoid/arytenoid, p < 0.001) was a significant factor influencing the heterogeneity in the diagnostic performance of the CT studies. CONCLUSIONS: In conclusion, MRI has significantly higher sensitivity than CT for detecting cartilage invasion in patients with laryngo-hypopharyngeal cancer, without a significant difference in the specificity. KEY POINTS: • MRI has significantly higher sensitivity than CT for detecting cartilage invasion in patients with laryngo-hypopharyngeal cancer.


Asunto(s)
Neoplasias Hipofaríngeas/diagnóstico , Imagen por Resonancia Magnética/métodos , Estadificación de Neoplasias/métodos , Tomografía Computarizada por Rayos X/métodos , Cartílago/diagnóstico por imagen , Humanos , Invasividad Neoplásica
2.
Eur Radiol ; 30(1): 346-356, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31338651

RESUMEN

OBJECTIVES: To investigate whether clinical condition, imaging session, and locations affect repeatability of amide proton transfer-weighted (APTw) magnetic resonance imaging (MRI) in the brain. MATERIALS AND METHODS: Three APTw MRI data sets were acquired, involving two intrasession scans and one intersession scan for 19 healthy, 15 glioma, and 12 acute stroke adult participants (mean age 53.8, 54.6, and 68.5, respectively) on a 3T MR scanner. The mean APTw signals from five locations in healthy brain (supratentorial and infratentorial locations) and from entire tumor and stroke lesions (supratentorial location) were calculated. The within-subject coefficient of variation (wCV) and intraclass correlation coefficient (ICC) were calculated for each clinical conditions, image sessions, and anatomic locations. Differences in APTw signals between sessions were analyzed using repeated-measures analysis of variance. RESULTS: The ICC and wCV were 0.96 (95% confidence interval [CI], 0.91-0.99) and 16.1 (12.6-21.3) in glioma, 0.93 (0.82-0.98) and 15.0 (11.4-20.6) in stroke, and 0.84 (0.72-0.91) and 34.0 (28.7-41.0) in healthy brain. There were no significant differences in APTw signal between three sessions, irrespective of disease condition and location. The ICC and wCV were 0.85 (0.68-0.94) and 27.4 (21.8-35.6) in supratentorial, and 0.44 (- 0.18 to 0.76) and 32.7 (25.9 to 42.9) in infratentorial locations. There were significant differences in APTw signal between supra- (mean, 0.49%; 95% CI, 0.38-0.61) and infratentorial locations (1.09%, 0.98-1.20; p < 0.001). CONCLUSION: The repeatability of APTw signal was excellent in supratentorial locations, while it was poor in infratentorial locations due to severe B0 inhomogeneity and susceptibility which affects MTR asymmetry. KEY POINTS: • In supratentorial locations, APTw MRI showed excellent intrasession and intersession repeatability in brains of healthy controls and patients with glioma, as well as in stroke-affected regions. • APTw MRI showed excellent repeatability in supratentorial locations, but poor repeatability in infratentorial locations. • Considering poor repeatability in the infratentorial locations, the use of APTw MRI in longitudinal assessment in infratentorial locations is not indicated.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Glioma/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Accidente Cerebrovascular/diagnóstico por imagen , Adulto , Anciano , Algoritmos , Amidas , Encéfalo/patología , Neoplasias Encefálicas/patología , Femenino , Glioma/patología , Humanos , Masculino , Persona de Mediana Edad , Protones
3.
Materials (Basel) ; 12(18)2019 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-31500244

RESUMEN

The objective of the present study is to demonstrate the versatility of the digital light processing (DLP) technique particularly when using a freeze-cast ceramic layer as the feedstock, which can manufacture porous calcium phosphate (CaP) scaffolds with arbitrarily designed macroporous structures with tailored microporous frameworks specially designed for bone scaffold applications. For this goal, we employed camphene-camphor as the freezing vehicle and porogen for the preparation of photocurable CaP suspensions containing diurethane dimethacrylate (UDMA) monomers. After freeze-casting, the CaP suspensions could be solidified at controlled temperatures (~33-38 °C) and then be photopolymerized by DLP. All produced CaP scaffolds fairly resembled the designed macroporous structures (the gyroid structure with two interpenetrating macropore networks). In addition, numerous micropores were created in the CaP filaments, while the microporosity increased with increasing the camphene-camphor amount from 40 vol % to 60 vol %. As a consequence, compressive strength and modulus of hierarchically porous CaP scaffolds decreased due to an increase in overall porosity. However, reasonable mechanical properties could be obtained at high porosities owing to the CaP frameworks constructed in a periodic manner. In addition, excellent water penetration capability, biocompatibility, and apatite-forming ability were obtained, which were attributed to the microporous CaP frameworks with good pore interconnectivity and large surface area.

4.
PLoS One ; 14(8): e0220603, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31386679

RESUMEN

BACKGROUND: The black-blood (BB) technique was developed to suppress the signal from blood and cerebrospinal fluid (CSF) to provide improved depiction of vessel walls. PURPOSE: The aim was to compare three-dimensional turbo spin echo T1-weighted imaging (3D TSE T1WI) with or without two BB techniques (delay alternating with nutation for tailored excitation [DANTE], and improved motion-sensitized driven equilibrium [iMSDE]) for high-resolution magnetic resonance imaging (HR-MRI) of the vessel walls of intracranial arteries. STUDY TYPE: Prospective. POPULATION: Fourteen healthy volunteers who underwent 3D T1WI for examination of intracranial vessel walls. FIELD STRENGTH/SEQUENCE: 3 Tesla, 3D TSE T1WI (SPACE and BrainVIEW) and BB (DANTE and iMSDE). ASSESSMENT: SPACE with or without DANTE, and BrainVIEW with or without iMSDE, were acquired in each subject. Two neuroradiologists independently assessed image quality, vessel wall delineation, BB effect, CSF, and acceptability using visual scoring systems, and measured signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in vessel walls, lumen, and CSF, while blinded to the presence and type of BB technique used. STATISTICAL TESTS: Repeated measures ANOVA or Friedman tests were performed for the comparisons, followed by Bonferroni correction. RESULTS: The 3T T1WI sequences without BB are significantly superior in vessel wall delineation (P = 0.001). Black CSF scores were lower in SPACE with DANTE than SPACE without DANTE, and in BrainVIEW without iMSDE than SPACE without DANTE (P < 0.001). However, there were no significant differences in BB effect, image quality, and acceptability between the four 3D T1WI sequences (p > .05). The SNRVessel wall, CNRWall-Lumen, and CNRWall-CSF were higher (all p < .001) on SPACE with and without DANTE than on BrainVIEW with and without iMSDE. SNRLumen were higher (all p < .001) on BrainVIEW with and without iMSDE than on SPACE with and without DANTE. SNRCSF was higher (all p < .001) on BrainVIEW with iMSDE than on SPACE with DANTE. DATA CONCLUSION: Both 3D TSE T1WI sequences were acceptable for intracranial vessel wall evaluation, with or without BB techniques. Therefore, BB techniques may not necessarily be required with 3D TSE T1WI with a long ETL and TR (below 1160 ms).


Asunto(s)
Vasos Sanguíneos/diagnóstico por imagen , Encéfalo/irrigación sanguínea , Angiografía por Resonancia Magnética/métodos , Adulto , Anciano , Vasos Sanguíneos/citología , Angiografía Cerebral/métodos , Angiografía Cerebral/normas , Endotelio Vascular/diagnóstico por imagen , Femenino , Voluntarios Sanos , Humanos , Angiografía por Resonancia Magnética/normas , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Relación Señal-Ruido , Túnica Media/diagnóstico por imagen
5.
Eur Radiol ; 29(8): 4077-4087, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30617485

RESUMEN

OBJECTIVE: To investigate the diagnostic performance of perfusion CT for prediction of hemorrhagic transformation in acute ischemic stroke. METHODS: A computerized literature search of Ovid MEDLINE and EMBASE was conducted up to October 29, 2018. Search terms included acute ischemic stroke, hemorrhagic transformation, and perfusion CT. Studies assessing the diagnostic performance of perfusion CT for prediction of hemorrhagic transformation in acute ischemic stroke were included. Two reviewers independently evaluated the eligibility of the studies. A bivariate random effects model was used to calculate the pooled sensitivity and pooled specificity. Multiple subgroup analyses were performed. RESULTS: Fifteen original articles with a total of 1134 patients were included. High blood-brain barrier permeability and hypoperfusion status derived from perfusion CT are associated with hemorrhagic transformation. The pooled sensitivity and specificity were 84% (95% CI, 71-91%) and 74% (95% CI, 67-81%), respectively. The area under the hierarchical summary receiver operating characteristic curve was 0.84 (95% CI, 0.81-0.87). The Higgins I2 statistic demonstrated that heterogeneity was present in the sensitivity (I2 = 80.21%) and specificity (I2 = 85.94%). CONCLUSION: Although various perfusion CT parameters have been used across studies, the current evidence supports the use of perfusion CT to predict hemorrhagic transformation in acute ischemic stroke. KEY POINTS: • High blood-brain barrier permeability and hypoperfusion status derived from perfusion CT were associated with hemorrhagic transformation. • Perfusion CT has moderate diagnostic performance for the prediction of hemorrhagic transformation in acute ischemic stroke. • The pooled sensitivity was 84%, and the pooled specificity was 74%.


Asunto(s)
Isquemia Encefálica/diagnóstico por imagen , Isquemia Encefálica/patología , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/patología , Tomografía Computarizada por Rayos X/métodos , Barrera Hematoencefálica/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Isquemia Encefálica/complicaciones , Humanos , Valor Predictivo de las Pruebas , Curva ROC , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Accidente Cerebrovascular/complicaciones
6.
Materials (Basel) ; 11(9)2018 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-30217045

RESUMEN

This study demonstrates the usefulness of the lithography-based ceramic 3-dimensional printing technique with a specifically designed top-down process for the production of porous calcium phosphate (CaP) ceramic scaffolds with tailored pore orientations and mechanical properties. The processing parameters including the preparation of a photocurable CaP slurry with a high solid loading (φ = 45 vol%), the exposure time for photocuring process, and the initial designs of the porous scaffolds were carefully controlled. Three types of porous CaP scaffolds with different pore orientations (i.e., 0°/90°, 0°/45°/90°/135°, and 0°/30°/60°/90°/120°/150°) were produced. All the scaffolds exhibited a tightly controlled porous structure with straight CaP frameworks arranged in a periodic pattern while the porosity was kept constant. The porous CaP scaffold with a pore orientation of 0°/90° demonstrated the highest compressive strength and modulus due to a number of CaP frameworks parallel to the loading direction. On the other hand, scaffolds with multiple pore orientations may exhibit more isotropic mechanical properties regardless of the loading directions. The porous CaP scaffolds exhibited an excellent in vitro apatite-forming ability in a stimulated body fluid (SBF) solution. These findings suggest that porous CaP scaffolds with tailored pore orientations may provide tunable mechanical properties with good bone regeneration ability.

7.
Food Sci Biotechnol ; 27(1): 277-282, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30263750

RESUMEN

Ethyl carbamate is naturally occurring compound, commonly found in many fermented foods and alcoholic beverages. During the process of plum wine production, ethyl carbamate can be formed. To this date, limited studies were conducted to monitor the ethyl carbamate in the plum wine brewed in-house. The objective of this study was to analyze the ethyl carbamates in plum wine, that were produced in differently: in-house and commercial production. A total of 33 plum wines were analyzed. The levels of ethyl carbamate ranged from N.D to 352.7 µg/kg in plum wines available in Korea. The current level of ethyl carbamate in plum wine was below the governmental regulation. However, continuous monitoring and further develop a strategy to reduce the level of ethyl carbamate in plum wine is in need, as the highest level of ethyl carbamate in plum wine is near the governmental standard (400 µg/kg).

8.
J Food Sci ; 81(1): T262-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26661512

RESUMEN

In this study, the effect of food additives such as iron sulfate, magnesium sulfate, zinc sulfate, citric acid, gallic acid, and ascorbic acid on the reduction of 4(5)-methylimidazole (4(5)-MI) was investigated using a soy sauce model system. The concentration of 4(5)-MI in the soy sauce model system with 5% (v/v) caramel colorant III was 1404.13 µg/L. The reduction rate of 4(5)-MI level with the addition of 0.1M additives followed in order: iron sulfate (81%) > zinc sulfate (61%) > citric acid (40%) > gallic acid (38%) > ascorbic acid (24%) > magnesium sulfate (13%). Correlations between 4(5)-MI levels and the physicochemical properties of soy sauce, including the amount of caramel colorant, pH value, and color differences, were determined. The highest correlations were found between 4(5)-MI levels and the amount of caramel colorant and pH values (r(2) = 0.9712, r(2) = 0.9378). The concentration of caramel colorants in 8 commercial soy sauces were estimated, and ranged from 0.01 to 1.34% (v/v).


Asunto(s)
Carcinógenos/análisis , Color , Aditivos Alimentarios , Manipulación de Alimentos , Imidazoles/análisis , Alimentos de Soja/análisis , Ácido Ascórbico , Carbohidratos , Ácido Cítrico , Compuestos Ferrosos , Ácido Gálico , Concentración de Iones de Hidrógeno , Reacción de Maillard , Modelos Biológicos , Glycine max , Sulfato de Zinc
9.
Skeletal Radiol ; 42(2): 239-47, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22669731

RESUMEN

PURPOSE: The aim of this work is to prospectively compare the effectiveness of iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL), T2-weighted fast spin-echo (FSE), and spoiled gradient-echo (SPGR) MR imaging to frequency selective fat suppression (FSFS) protocols for minimizing metallic artifacts in postoperative ankles with metallic hardware. MATERIALS AND METHODS: The T2-weighted and SPGR imaging with IDEAL and FSFS were performed on 21 ankles of 21 patients with metallic hardware. Two musculoskeletal radiologists independently analyzed techniques for visualization of ankle ligaments and articular cartilage, uniformity of fat saturation, and relative size of the metallic artifacts. A paired t test was used for statistical comparisons of MR images between IDEAL and FSFS groups. RESULTS: IDEAL T2-weighted FSE and SPGR images enabled significantly improved visualization of articular cartilage (p < 0.05), the size of metallic artifact (p < 0.05), and the uniformity of fat saturation (p < 0.05). However, no significant improvement was found in the visibility of ligaments. CONCLUSIONS: IDEAL T2-weighted FSE and SPGR imaging effectively reduces the degree of tissue-obscuring artifacts produced by fixation hardware in ankle joints and improves image quality compared to FSFS T2-weighted FSE and SPGR imaging. However, visibility of ligaments was not improved using IDEAL imaging.


Asunto(s)
Traumatismos del Tobillo/patología , Traumatismos del Tobillo/cirugía , Artefactos , Fracturas Óseas/patología , Fracturas Óseas/cirugía , Fijadores Internos , Imagen por Resonancia Magnética/métodos , Adolescente , Adulto , Femenino , Humanos , Masculino , Metales , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
10.
PLoS One ; 7(3): e32778, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22412925

RESUMEN

It has been reported that human mesenchymal stem cells (MSCs) can transfer mitochondria to the cells with severely compromised mitochondrial function. We tested whether the reported intercellular mitochondrial transfer could be replicated in different types of cells or under different experimental conditions, and tried to elucidate possible mechanism. Using biochemical selection methods, we found exponentially growing cells in restrictive media (uridine(-) and bromodeoxyuridine [BrdU](+)) during the coculture of MSCs (uridine-independent and BrdU-sensitive) and 143B-derived cells with severe mitochondrial dysfunction induced by either long-term ethidium bromide treatment or short-term rhodamine 6G (R6G) treatment (uridine-dependent but BrdU-resistant). The exponentially growing cells had nuclear DNA fingerprint patterns identical to 143B, and a sequence of mitochondrial DNA (mtDNA) identical to the MSCs. Since R6G causes rapid and irreversible damage to mitochondria without the removal of mtDNA, the mitochondrial function appears to be restored through a direct transfer of mitochondria rather than mtDNA alone. Conditioned media, which were prepared by treating mtDNA-less 143B ρ(0) cells under uridine-free condition, induced increased chemotaxis in MSC, which was also supported by transcriptome analysis. Cytochalasin B, an inhibitor of chemotaxis and cytoskeletal assembly, blocked mitochondrial transfer phenomenon in the above condition. However, we could not find any evidence of mitochondrial transfer to the cells harboring human pathogenic mtDNA mutations (A3243G mutation or 4,977 bp deletion). Thus, the mitochondrial transfer is limited to the condition of a near total absence of mitochondrial function. Elucidation of the mechanism of mitochondrial transfer will help us create a potential cell therapy-based mitochondrial restoration or mitochondrial gene therapy for human diseases caused by mitochondrial dysfunction.


Asunto(s)
ADN Mitocondrial/genética , Células Madre Mesenquimatosas/metabolismo , Mitocondrias/metabolismo , Mutación , Secuencia de Bases , Línea Celular , Movimiento Celular/genética , Supervivencia Celular/genética , Técnicas de Cocultivo , Medios de Cultivo Condicionados , Perfilación de la Expresión Génica , Humanos , Células Madre Mesenquimatosas/citología , Repeticiones de Microsatélite/genética , Datos de Secuencia Molecular , Factores de Tiempo
11.
Aging Cell ; 10(1): 148-57, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21108727

RESUMEN

Human diploid fibroblasts have the capacity to complete a finite number of cell divisions before entering a state of replicative senescence characterized by growth arrest, changes in morphology, and altered gene expression. Herein, we report that interaction with extracellular matrix (ECM) from young cells is sufficient to restore aged, senescent cells to an apparently youthful state. The identity of the restored cells as having been derived from senescent cells has been confirmed by a variety of methods, including time lapse live cell imaging and DNA finger print analysis. In addition to cell morphology, phenotypic restoration was assessed by resumption of proliferative potential, growth factor responsiveness, reduction of intracellular reactive oxygen species levels, recovery of mitochondrial membrane potential, and increased telomere length. Mechanistically, we find that both Ku and SIRT1 are induced during restoration and are required for senescent cells to return to a youthful phenotype. These observations demonstrate that human cellular senescence is profoundly influenced by cues from the ECM, and that senescent cell plasticity is much greater than that was previously believed to be the case.


Asunto(s)
Antígenos Nucleares/metabolismo , Proteínas de Unión al ADN/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo , Sirtuina 1/metabolismo , Antígenos Nucleares/genética , División Celular , Proliferación Celular , Células Cultivadas , Senescencia Celular/fisiología , Niño , Dermatoglifia del ADN , Proteínas de Unión al ADN/genética , Diploidia , Fibroblastos/citología , Expresión Génica/fisiología , Humanos , Recién Nacido , Autoantígeno Ku , Masculino , Potencial de la Membrana Mitocondrial/fisiología , Especies Reactivas de Oxígeno/metabolismo , Recuperación de la Función , Sirtuina 1/genética , Telómero/ultraestructura
14.
Forensic Sci Int ; 149(2-3): 267-9, 2005 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-15749371

RESUMEN

Sequence polymorphism of the mitochondrial DNA (mtDNA) control region, hypervariable regions HVR I, HVR II and HVR III, from 51 unrelated China Han (Yan Bian area) were determined by PCR amplification and cycle sequencing.


Asunto(s)
ADN Mitocondrial/genética , Etnicidad/genética , Variación Genética , Genética de Población , Haplotipos , China , Dermatoglifia del ADN/métodos , Frecuencia de los Genes , Humanos , Reacción en Cadena de la Polimerasa , Secuencias Repetidas en Tándem
15.
Cell Biol Int ; 28(12): 943-8, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15566963

RESUMEN

To elucidate the function of PLCgamma1, we have investigated the proteins that bind to its SH (Src homology) domain. Immunoscreening was performed with purified antisera specific for SH223 (two SH2 and one SH3)-binding proteins. Several immunoreactive clones were identified as putative binding proteins and one of them was identified as synapsin IIb. We demonstrate a stable association between PLCgamma1 and synapsin IIb, which binds the carboxyl terminal SH2 and SH3 domains of the enzyme and inhibits it.


Asunto(s)
Sinapsinas/metabolismo , Fosfolipasas de Tipo C/química , Fosfolipasas de Tipo C/metabolismo , Dominios Homologos src/inmunología , Animales , Sitios de Unión/inmunología , Sitios de Unión/fisiología , Inhibidores Enzimáticos/inmunología , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Inmunoquímica , Fosfolipasa C gamma , Unión Proteica/inmunología , Unión Proteica/fisiología , Conejos , Ratas , Sinapsinas/inmunología , Sinapsinas/farmacología , Fosfolipasas de Tipo C/antagonistas & inhibidores
16.
Forensic Sci Int ; 141(2-3): 189-92, 2004 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-15062961

RESUMEN

Allele and genotype frequencies for the 15 STR loci (FGA, vWA, MBP-L, MBP-H, HumTh01, D3S1358, D3S2406, D5S818, D7S820, D8S1179, D13S317, D18S51, D19S253, and D21S11) and two VNTR loci (D1S80 and D17S5) in a sample of unrelated Koreans were determined.


Asunto(s)
Frecuencia de los Genes , Genética de Población , Polimorfismo Genético , Secuencias Repetidas en Tándem , Dermatoglifia del ADN/métodos , Genotipo , Humanos , Corea (Geográfico)
17.
Forensic Sci Int ; 138(1-3): 116-8, 2003 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-14642729

RESUMEN

Allele frequencies for the nine tetrameric short tandem repeats (STR) loci D3S1358, vWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, and D7S820 (AmpFlSTR Profiler Plus PCR amplification kit, PE Applied Biosystems) and two pentameric STR loci Penta D and Penta E (PowerPlex 16 system, Promega Corporation) were determined in a population sample of unrelated China Han.


Asunto(s)
Etnicidad/genética , Frecuencia de los Genes , Genética de Población , Secuencias Repetidas en Tándem , China , Dermatoglifia del ADN/métodos , Humanos , Reacción en Cadena de la Polimerasa
18.
Int J Legal Med ; 116(2): 74-8, 2002 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12056524

RESUMEN

Sequencing the mitochondrial control region is very useful for individual identification when conventional DNA typing using autosomal STRs is unavailable. However, low discriminatory power is a problem and another polymorphic locus within the mitochondrial genome is necessary. The cytochrome B (MTCYB) gene, which has undergone several changes during evolution, may be a good candidate for this purpose. Here the sequencing data of the MTCYB gene of 98 unrelated Koreans is presented. A total of 30 polymorphic sites were found which were distributed evenly along the gene. All were nucleotide substitutions and no insertions/deletions were noted. A total of 22 different MTCYB lineages were revealed. Out of 22 different control region lineages with 79 samples which shared the same D-loop sequence with some others within a lineage, 10 lineages with 37 samples could be sub-grouped according to different MTCYB sequences. Some issues concerning the MTCYB gene polymorphism are discussed.


Asunto(s)
Grupo Citocromo b/genética , ADN Mitocondrial/genética , Polimorfismo Genético , ADN Mitocondrial/sangre , Femenino , Marcadores Genéticos , Genotipo , Humanos , Técnicas In Vitro , Corea (Geográfico)
19.
Exp Parasitol ; 102(3-4): 143-9, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12856309

RESUMEN

Three new members of the cysteine proteinase gene family of Paragonimus westermani have been isolated and classified. Comparisons of the predicted amino acid sequences of PwCP2 (U69121), PwCP4 (U56958), and PwCP5 (U33215) were performed with those of the previously reported PwCP1 (U69120) and PwCP3 (U56865) sequence. The amino acid alignment showed conservation of the cysteine, histidine, and asparagine residue that form the catalytic triad. With 57 cysteine proteinases including PwCP1-5, we conducted phylogenetic analysis using neighbor joining method (NJ). A resultant unrooted tree revealed that PwCP1-5 were clustered with cruzipain-like or cathepsin L-like cysteine proteinases. More detailed phylogenetic analyses with a reduced alignment set (22 cysteine proteinases) were performed by NJ and maximum parsimony (MP) methods. The results showed coincidently that PwCP1, 2, 3, and 4 belonged to the group of previously reported cruzipain-like cysteine proteinases (bootstrapping values of 97 and 100% in the MP and NJ trees) but PwCP5 to cathepsin L-like cysteine proteinases (the value of 76 and 100% in MP and NJ trees). Within the cruzipain-like clade, PwCP2 and 4 were found to be the most closely related. PwCP 2, 3, and 4 have five of six cruzipain signature sequences known previously, whereas PwCP5 do not have any cruzipain sequences in the corresponding sites. We found that two signature candidate sites (Gly 174, Asn 175--human cathepsin L numbering) for cathepsin L-like group are conserved in PwCP5, which are conserved within cathepsin L-like group and also different from those of cruzipain and other cysteine proteinase groups. PwCP5 has three-residue insertion (hydrophilic residues, Ser-Tyr-Gly) within the position corresponding to S3 subsite of SmCL2. Compared to the two-residue insertion (Tyr-Gly) in SmCL2, the three-residue insertion appeared in PwCP5 may bring bigger difference in substrate specificity between PwCP1-4 (cruzipain) and PwCP5 (cathepsin L-like). Such presumption is quite plausible considering extremely lower amino acid sequence similarity (18.2%) between PwCP1-4 and PwCP5. The present study is worthy of reporting one another case, the third organism after Schistosoma mansoni and Schistosoma japonicum, which has the two kinds of genes encoding both the cruzipain and cathepsin L-like cysteine proteinases. In addition, the fact that most of cysteine proteinases from P. westermani are cruzipain-like type implies strongly that a new powerful drug for paragonimiasis could be designed and developed if we focus on the exploration of anti-agents against P. westermani cruzipain-like cysteine proteinases.


Asunto(s)
Cisteína Endopeptidasas/química , Cisteína Endopeptidasas/clasificación , Paragonimus/enzimología , Secuencia de Aminoácidos , Animales , Astacoidea , Secuencia de Bases , Cisteína Endopeptidasas/genética , Perros , Regulación Enzimológica de la Expresión Génica , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Especificidad por Sustrato
20.
Kisaengchunghak Chapchi ; 21(1): 58-73, 1983 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12902670

RESUMEN

The intestinal lesions were studied in dog metagonimiasis by reinfection. The metacercariae of M. yokogawai were collected from naturally infected sweetfish. A total of twenty dogs were divided into three groups; control, primary infection and reinfection groups. The 18 dogs were infected with 10,000 metacercariae; the 5 dogs in primary infection group were killed at the 5 days in 1 week, 4 weeks, 6 weeks after the infection. The remaining 13 dogs were kept for nine weeks, and challenged again with 5,000 metacercaricae. The reinfected dogs were killed at the 1 day, 3 days, 5 days and 1 week, 2 weeks, 4 weeks, 6 weeks, 8 weeks respectively. The chronologic changes of the intestinal lesions in both groups, the worm recovery rate, and distribution patten were examined by gross observation, light and scanning electron microscopies. The results were summarized as follows: 1. Worm recovery rate in primary infection group ranged from 19.8% to 37.8%. The rates were 6.3% to 16.3% in reinfected dogs within 5 dats. And the ratio of young worms collected to old ones was 1:1.83. In primary infection group, the collected worms were distributed in upper portion of the small intestine, while the distribution of worms shifted down to the lower portion of the small intestine in reinfection group. 2. In primary infection group, gross pathologic findings of intestinal mucosa began to appear in the 5th day and the 1st week after infection. The changes were effacement of transverse folds, watery or serous intestinal content, and enlargement of Peyer's patches as well as mesenteric lymph nodes. After the 4 week of infection, these findings returned to normal. In the reinfection group, these findings did occur again, but were lighter in degree when compared with primary infection group in early phase of infection. Again the gross changes returned to normal in two weeks which resolved earlier than in promary infection groups. 3, By histopathologic observations, mucosal changes such as blunted, adhered villi with hyperplasia of crypt epithelium, stromal changes, edema, and inflammatory cell infiltration were observed. These regressed mucosal changes were returned to almost normal, except for inflammatory cell infiltration. The reinfected dogs showed less severe lesions of the small intestine, with shorter period of the changes especially in aspect of villous changes. 4. By the scanning electron microscopy, the histopathological findings of villi lesions were also confirmed. From the above results, it was inferred that the so-called spontaneous and/or self cure phenomena were of negligible importance in metagonimiasis in dogs. In the chronologic observations of pathologic process in intestine, it was also suggested that the host immunity tend to recover the intestinal integrity. And early invasion of young worms to the Lieberkuhn's crypt was considered as the primary cause of lesions of villi.

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