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1.
Chinese Journal of Pediatrics ; (12): 600-605, 2023.
Artículo en Chino | WPRIM | ID: wpr-985916

RESUMEN

Objective: To investigate the relationship between genetic polymorphisms of cytochrome P450 2C19 (CYP2C19) and the efficacy of Helicobacter pylori (Hp) eradication therapy in children. Methods: The retrospective cohort study was conducted on 125 children with gastroscopy and positive rapid urease test (RUT) from September 2016 to December 2018 who presented to the Children's Hospital of Zhejiang University School of Medicine due to gastrointestinal symptoms including nausea, vomiting, abdominal pain, bloating, acid reflux, heartburn, chest pain, vomiting blood and melena. Hp culture and drug susceptibility test were carried out with gastric antrum mucosa before treatment. All the patients completed 2 weeks of standardized Hp eradication therapy and had 13C urea breath test 1 month after that, which was used to evaluate the curative effect. The DNA of gastric mucosa after RUT was analyzed and CYP2C19 gene polymorphism was detected. Children were grouped according to metabolic type. Combined with the results of Hp culture and drug susceptibility, the relationship between CYP2C19 gene polymorphism and the efficacy of Hp eradicative treatment was analyzed in children. Chi square test was used for row and column variables, and Fisher exact test was used for comparison between groups. Results: One hundred and twenty five children were enrolled in the study, of whom 76 were males and 49 females. The genetic polymorphism of CYP2C19 in these children found poor metabolizer (PM) of 30.4% (38/125), intermediate metabolizer (IM) of 20.8% (26/125), normal metabolizer (NM) of 47.2% (59/125), rapid metabolizer (RM) of 1.6% (2/125), and ultrarapid metabolizer (UM) of 0. There were statistically significant in positive rate of Hp culture among these groups (χ2=124.00, P<0.001). In addition, the successful rates of Hp eradication in PM, IM, NM and RM genotypes were 84.2% (32/38), 53.8% (14/26), 67.8% (40/59), and 0, respectively, with significant differences (χ2=11.35, P=0.010); those in IM genotype was significantly lower than that in PM genotype (P=0.011). With the same standard triple Hp eradicative regimen, the successful rate of Hp eradication for IM type was 8/19, which was lower than that of PM (80.0%, 24/30) and NM type (77.3%, 34/44) (P=0.007 and 0.007, respectively). There was a significant difference in the efficacy of Hp eradication treatment among different genotypes (χ2=9.72, P=0.008). According to the clarithromycin susceptibility result, the successful rate of Hp eradication treatment for IM genotype was 4/15 in the sensitive group and 4/4 in the drug-resistant group (χ2=6.97, P=0.018). Conclusions: The genetic polymorphism of CYP2C19 in children is closely related to the efficacy of Hp eradication treatment. PM has a higher successful rate of eradication treatment than the other genotypes.


Asunto(s)
Femenino , Masculino , Humanos , Niño , Citocromo P-450 CYP2C19/genética , Helicobacter pylori , Estudios Retrospectivos , Genotipo , Dolor Abdominal
2.
Chinese Journal of Medical Genetics ; (6): 256-260, 2011.
Artículo en Chino | WPRIM | ID: wpr-326952

RESUMEN

<p><b>OBJECTIVE</b>To investigate the relationship of susceptibility loci in chromosomes 1q21-25 and 6p21-25 and schizophrenia subtypes in Chinese population.</p><p><b>METHODS</b>A genomic scan and parametric and non-parametric analyses were performed on 242 individuals from 36 schizophrenia pedigrees, including 19 paranoid schizophrenia and 17 undifferentiated schizophrenia pedigrees, from Henan province of China using 5 microsatellite markers in the chromosome region 1q21-25 and 8 microsatellite markers in the chromosome region 6p21-25, which were the candidates of previous studies. All affected subjects were diagnosed and typed according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revised (DSM-IV-TR; American Psychiatric Association, 2000). All subjects signed informed consent.</p><p><b>RESULTS</b>In chromosome 1, parametric analysis under the dominant inheritance mode of all 36 pedigrees showed that the maximum multi-point heterogeneity Log of odds score method (HLOD) score was 1.33 (α = 0.38). The non-parametric analysis and the single point and multi-point nonparametric linkage (NPL) scores suggested linkage at D1S484, D1S2878, and D1S196. In the 19 paranoid schizophrenias pedigrees, linkage was not observed for any of the 5 markers. In the 17 undifferentiated schizophrenia pedigrees, the multi-point NPL score was 1.60 (P= 0.0367) at D1S484. The single point NPL score was 1.95(P= 0.0145) and the multi-point NPL score was 2.39 (P= 0.0041) at D1S2878. Additionally, the multi-point NPL score was 1.74 (P= 0.0255) at D1S196. These same three loci showed suggestive linkage during the integrative analysis of all 36 pedigrees. In chromosome 6, parametric linkage analysis under the dominant and recessive inheritance and the non-parametric linkage analysis of all 36 pedigrees and the 17 undifferentiated schizophrenia pedigrees, linkage was not observed for any of the 8 markers. In the 19 paranoid schizophrenias pedigrees, parametric analysis showed that under recessive inheritance mode the maximum single-point HLOD score was 1.26 (α = 0.40) and the multi-point HLOD was 1.12 (α = 0.38) at D6S289 in the chromosome 6p23. In nonparametric analysis, the single-point NPL score was 1.52 (P= 0.0402) and the multi-point NPL score was 1.92 (P= 0.0206) at D6S289.</p><p><b>CONCLUSION</b>Susceptibility genes correlated with undifferentiated schizophrenia pedigrees from D1S484, D1S2878, D1S196 loci, and those correlated with paranoid schizophrenia pedigrees from D6S289 locus are likely present in chromosome regions 1q23.3 and 1q24.2, and chromosome region 6p23, respectively.</p>


Asunto(s)
Adulto , Humanos , Persona de Mediana Edad , Adulto Joven , Cromosomas Humanos , Ligamiento Genético , Sitios Genéticos , Predisposición Genética a la Enfermedad , Repeticiones de Microsatélite , Genética , Esquizofrenia , Genética
3.
Journal of Central South University(Medical Sciences) ; (12): 241-245, 2007.
Artículo en Chino | WPRIM | ID: wpr-813900

RESUMEN

OBJECTIVE@#To investigate the correlation between male infertility and Y chromosome microdeletions of azoospermia factor (AZF) regions, and to establish a reliable genetic diagnosis in idiopathic infertile male patients with azoospermia or severe oligozoospermia.@*METHODS@#Multiplex PCR amplification of 6 sequence-tagged sites in AZF regions of the Y chromosome was examined among 100 normal karyotype male patients with azoospermia or oligozoospermia.@*RESULTS@#Four patients (4%) had Y chromosome microdeletions, the microdeletions of 3 patients were idiopathic azoospermic and those of the other 1 patient were secretory azoospermia.@*CONCLUSION@#The PCR-based Y chromosome microdeletion screening is simple and effective in the diagnosis of patients with severe male infertility. Microdeletion of Y chromosome is one of the major causes of severe dyszooospermia.


Asunto(s)
Adulto , Humanos , Masculino , Azoospermia , Genética , Deleción Cromosómica , Cromosomas Humanos Y , Genética , Sitios Genéticos , Infertilidad Masculina , Diagnóstico , Genética , Cariotipificación , Oligospermia , Genética , Proteínas de Plasma Seminal , Genética
4.
Journal of Central South University(Medical Sciences) ; (12): 246-251, 2007.
Artículo en Chino | WPRIM | ID: wpr-813899

RESUMEN

OBJECTIVE@#To detect two exons of Duchenne muscular dystrophy (DMD) gene and a gender discrimination locus amelogenin gene by single cell triplex PCR, and to evaluate the possibility of this technique for preimplantation genetic diagnosis (PGD) in DMD family with DMD deletion mutation.@*METHODS@#Single lymphocytes from a normal male, a normal female, two DMD patients (exon 8 and 47 deleted, respectively) and single blastomeres from the couples treated by the in vitro fertilization pre-embryo transfer (IVF-ET) and without family history of DMD were obtained. Exons 8 and 47 of DMD gene were amplified by a triplex PCR assay, the amelogenin gene on X and Y chromosomes were co-amplified to analyze the correlation between embryo gender and deletion status.@*RESULTS@#In the normal single lymphocytes, the amplification rate of exons 8 and 47 of DMD and amelogenin gene were 93.8%, 93.8%, and 95.3% respectively. The false positive rate was 3.3%. In the exon 8 deleted DMD patient, the amplification rate of exon 47 of DMD and amelogenin gene was 95.8%, and the false positive rate was 3.3%. In the exon 47 deleted DMD patient, the amplification rate of exon 8 of DMD and amelogenin gene was 95.8%, and the false positive rate was 0. In the single blastomeres, the amplification rate of exons 8 and 47 of DMD and amelogenin gene was 82.5%, 80.0% and 77.5%, respectively, and the false positive rate was 0.@*CONCLUSION@#The single cell triplex PCR protocol for the detection of DMD and amelogenin gene is highly sensitive, specific and reliable, and can be used for PGD in those DMD families with DMD deletion mutation.


Asunto(s)
Femenino , Humanos , Masculino , Embarazo , Amelogenina , Genética , Blastómeros , Biología Celular , Metabolismo , Cromosomas Humanos X , Genética , Cromosomas Humanos Y , Genética , Análisis Citogenético , Métodos , Exones , Genética , Eliminación de Gen , Linfocitos , Biología Celular , Metabolismo , Distrofia Muscular de Duchenne , Sangre , Diagnóstico , Genética , Reacción en Cadena de la Polimerasa , Métodos , Diagnóstico Preimplantación , Métodos
5.
Journal of Central South University(Medical Sciences) ; (12): 264-267, 2007.
Artículo en Chino | WPRIM | ID: wpr-813896

RESUMEN

OBJECTIVE@#To identify the origin of the marker chromosome in a patient with chromosome aberration, and to provide the precise genetic diagnosis.@*METHODS@#Comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH) were performed to detect the known small marker chromosome in this patient.@*RESULTS@#The small marker chromosome originated from chromosome 13 pter->q12.@*CONCLUSION@#CGH and FISH can be used to detect the small marker chromosome, which is convenient and quick in detecting the origin of small marker chromosome.


Asunto(s)
Femenino , Humanos , Aberraciones Cromosómicas , Deleción Cromosómica , Cromosomas Humanos Par 13 , Genética , Genoma Humano , Hibridación Fluorescente in Situ , Métodos , Cariotipificación , Hibridación de Ácido Nucleico , Métodos
6.
Journal of Central South University(Medical Sciences) ; (12): 466-472, 2007.
Artículo en Chino | WPRIM | ID: wpr-813859

RESUMEN

OBJECTIVE@#To investigate the biological characteristics of endothelial progenitor cells (EPCs) from the umbilical cord blood (UCB), and to evaluate their oncogenicity after long-term culture in vitro.@*METHODS@#The mononuclear cells (MNCs) were isolated from the UCB and cultured in MCDB131 medium supplemented with 20% FBS, VEGF and other growth factors. Morphology of the EPCs was observed, and the growth curve of the EPCs was investigated. Surface antigens of the EPCs were analyzed by the flow-cytometer. The capability of intaking the acetylated low-density lipoprotein (acLDL) of the EPCs was detected using fluoresencent chemical method. The vasoformative capability and genetic stability of EPCs were cultured in matrigel, and examined by karyotype analysis. The oncogenicity of EPCs was verified by the tumorigenesis test in athymic mouse and soft agar.@*RESULTS@#EPCs were successfully derived from the UCB, and could be passaged to at least 42(nd) generation and had strong abilities of proliferation, acLDL intake and vasoformation, but there was not oncogenicity. They expressed endothelial cell-surface antigens and maintained normal karyotype.@*CONCLUSION@#The EPCs with proliferative potential can be isolated from the UCB. They can be passaged in long-term cultures without oncogenicity, and can maintain normal karyotype. The EPCs can be served as a new type of cells in cell and gene therapy.


Asunto(s)
Animales , Humanos , Recién Nacido , Ratones , Antígenos de Superficie , Línea Celular , Proliferación Celular , Células Cultivadas , Células Endoteliales , Biología Celular , Metabolismo , Sangre Fetal , Biología Celular , Citometría de Flujo , Células HeLa , Péptidos y Proteínas de Señalización Intercelular , Farmacología , Cariotipificación , Ratones Desnudos , Neoplasias Experimentales , Patología , Células Madre , Biología Celular , Metabolismo , Factor A de Crecimiento Endotelial Vascular , Farmacología
7.
China Biotechnology ; (12)2006.
Artículo en Chino | WPRIM | ID: wpr-685055

RESUMEN

Objective: To establish a method for isolation and purification of fetal membrane derived adherent cells (FMDACs) , and investigate their biological characteristics. Method: FMDACs were isolated with trypsin inducing and cultured in vitro. FMDACs were induced to differentiate into osteoblasts and adipocytes. FACS and immunocytochemistry technique were used to examine the cell surface antigen. The genetic stability was verified by karyotype analysis. Results: FMDACs were successfully isolated and expanded in vitro. They had strong proliferative ability. FMDACs were positive for CD44 and CD29, but negative for CD34, CD14 and CD45. FMDACs were differentiated into osteoblasts and adipocytes after inducement. The karyotype was stable in the sixth-passaged FMDACs and the tumorigenicity was not found. Conclusion; FMDACs have the possibility of multipotent stem cells, which have strong capacities of self-renewal and multidirectional differentiation. The genetic background of FMDACs is stable. FMDACs may be used as a kind of novel seed cells for tissue engineering.

8.
Journal of Central South University(Medical Sciences) ; (12): 9-13, 2006.
Artículo en Chino | WPRIM | ID: wpr-813777

RESUMEN

OBJECTIVE@#To identify the promoter of human nicastrin (NCT) gene, a major component of gamma-secretase which is closely related with pathogenesis of Alzheimer's disease.@*METHODS@#Promoter of human Alzheimer's disease related gene, nicastrin, a 1768 bp fragment was firstly isolated from human genomic DNA by PCR. This fragment's 3 flanking end was 4 bp upstream to the start codon ATG (+1) of the gene. This fragment was used as template, a series of deleted fragments were amplified and constructed to the pGL3-Enhancer plasmid with the artificial designed linkers. The relative activity of their promoter in Hela cells was studied by dual-luciferase assay.@*RESULTS@#The 420 bp fragment showed the strongest activity, and the 237 bp fragment was the minimal fragment in length with activity.@*CONCLUSION@#The promoter of NCT is located at -432/-133 region upstream the translational start codon, while its basal promoter is between -359/-90 that drives the transcription of reporter gene in Hela cells.


Asunto(s)
Humanos , Enfermedad de Alzheimer , Genética , Secretasas de la Proteína Precursora del Amiloide , Clonación Molecular , Genes Reporteros , Genética , Células HeLa , Glicoproteínas de Membrana , Genética , Regiones Promotoras Genéticas , Genética
9.
Chinese Journal of Medical Genetics ; (6): 147-150, 2006.
Artículo en Chino | WPRIM | ID: wpr-263832

RESUMEN

<p><b>OBJECTIVE</b>To study the gene mutation in a patient with multiple exostoses, identify the disease-causing gene mutation.</p><p><b>METHODS</b>Polymerase chain reaction and DNA sequencing were used to screen the EXT1 or EXT2 gene mutation, while mismatch primer amplification and restriction endonuclease digestion were performed to confirm the mutation.</p><p><b>RESULTS</b>By DNA sequencing, a mutation in the seventh intron was detected and located at 26 bp of 3' splice site upstream in EXT1 gene, which was unreported before. Mismatch primer amplification and restriction fragment length polymorphism analysis suggested that this mutation was not detected in the normal control.</p><p><b>CONCLUSION</b>The mutation 1633-26(C-->A) may be the disease-causing mutation in this patient with multiple exostoses.</p>


Asunto(s)
Femenino , Humanos , Adulto Joven , Análisis Mutacional de ADN , Exostosis Múltiple Hereditaria , Genética , Mutación , N-Acetilglucosaminiltransferasas , Genética
10.
Chinese Journal of Medical Genetics ; (6): 376-379, 2005.
Artículo en Inglés | WPRIM | ID: wpr-280047

RESUMEN

<p><b>OBJECTIVE</b>To identify the pathogenic gene for a non-syndromic hearing loss family.</p><p><b>METHODS</b>Mutation analysis was carried out by polymerase chain reaction and direct sequencing of all exons of SLC26A4 (solute carrier family 26, member 4) gene.</p><p><b>RESULTS</b>Compound heterozygous mutations N392Y and S448X were detected in the proband of the family, heterozygous mutation S448X was detected in the father, heterozygous mutation N392Y was detected in the mother.</p><p><b>CONCLUSION</b>The proband's hearing loss resulted from the compound heterozygous mutations N392Y and S448X for SLC26A4 gene.</p>


Asunto(s)
Adulto , Femenino , Humanos , Masculino , Secuencia de Bases , Análisis Mutacional de ADN , Sordera , Diagnóstico por Imagen , Genética , Patología , Salud de la Familia , Proteínas de Transporte de Membrana , Genética , Datos de Secuencia Molecular , Mutación , Reacción en Cadena de la Polimerasa , Tomografía Computarizada por Rayos X
11.
Chinese Journal of Medical Genetics ; (6): 493-496, 2005.
Artículo en Inglés | WPRIM | ID: wpr-280017

RESUMEN

<p><b>OBJECTIVE</b>To construct a human source vector containing minidystrophin-EGFP fusion gene and investigate its expression in Cos-7 cells.</p><p><b>METHODS</b>The recombinant human source vector named pHrnDysG was constructed with PCR-clone methods. Three fragments of dystrophin gene were PCR amplified from normal human dystrophin gene cDNA (GenBank NM04006). These three fragments were ligated to generate a minidystrophin gene. The enhanced green fluorescent protein (EGFP) gene was fused to the C terminal of the minidystrophin gene, and then the pHrnDysG was finally obtained by cloning the fusion gene to pHrneo. Fluorescence microscope and RT-PCR were used to detect the expression of minidystrophin-EGFP fusion gene after the recombinant construct was transfected into Cos-7 cells by lipofectamine.</p><p><b>RESULTS</b>Restrictive enzyme digestion analysis and sequencing confirmed that pHrnDysG vector was constructed successfully. After the recombinant pHrnDysG was transfected to Cos-7 cells, RT-PCR demonstrated that the fusion gene was successfully transcribed, and the green fluorescence was observed at the cell membrane.</p><p><b>CONCLUSION</b>The minidystrophin-EGFP fusion gene mediated by pHrneo vector could express in Cos-7 cells and its products' localization in the cell membrane was the same as that of full length dystrophin. These results suggested that the recombinant human source vector pHrnDysG might be potentially used in studies on the gene therapy of Duchenne muscular dystrophy.</p>


Asunto(s)
Animales , Humanos , Células COS , Chlorocebus aethiops , Distrofina , Genética , Metabolismo , Vectores Genéticos , Genética , Proteínas Fluorescentes Verdes , Genética , Metabolismo , Microscopía Fluorescente , Modelos Genéticos , Proteínas Recombinantes de Fusión , Genética , Metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transfección
12.
Journal of Central South University(Medical Sciences) ; (12): 510-514, 2005.
Artículo en Chino | WPRIM | ID: wpr-813517

RESUMEN

OBJECTIVE@#To localize the gene of autosomal dominant familial dilated cardiomyopathy with conduction defect.@*METHODS@#A Chinese family which was diagnosed as dilated cardiomyopathy with conduction defect was studied. Venous blood (3 - 5 mL) from some family members was collected, and genomic DNA was extracted from the blood. Then whole genome wide scan was performed after excluding the known markers on the candidate loci (CMD1A, CMD1 E, CMD1F, and CMD1H) by two-point linkage analysis.@*RESULTS@#No significant evidence for linkage was found in the two point linkage analyses to the known markers in the analyzed family. And the whole genome wide scan showed the maximum LOD score reached 2.68 at marker D3S1614 ( at recombination fraction theta = 0).@*CONCLUSION@#The related gene in this kindred is located on 3q26 other than on CMD1A, CMD1H, CMD1E, and CMD1F.


Asunto(s)
Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Arritmias Cardíacas , Genética , Cardiomiopatía Dilatada , Genética , Cromosomas Humanos Par 3 , Genética , Ligamiento Genético , Repeticiones de Microsatélite , Linaje
13.
Journal of Central South University(Medical Sciences) ; (12): 657-659, 2005.
Artículo en Chino | WPRIM | ID: wpr-813455

RESUMEN

OBJECTIVE@#To investigate the source of the extra small chromosome in a patient with karyotype 45,X[115]/46,X + mar[45]/46,XY[29].@*METHODS@#The SRYgene was detected by PCR, and the chromosome Y probe that labeled with biotin was detected by fluorescence in situ hybridization.@*RESULTS@#SRY gene is detected positive and the mar chromosome showed positive signal with FISH in human chromosome Y probe pool.@*CONCLUSION@#The extra small chromosome is part of the chromosome Y.


Asunto(s)
Adolescente , Femenino , Humanos , Aberraciones Cromosómicas , Genes sry , Genética , Hibridación Fluorescente in Situ , Cariotipificación , Reacción en Cadena de la Polimerasa , Cromosomas Sexuales , Diferenciación Sexual , Genética , Síndrome de Turner , Genética
14.
Chinese Journal of Medical Genetics ; (6): 207-210, 2004.
Artículo en Chino | WPRIM | ID: wpr-328917

RESUMEN

<p><b>OBJECTIVE</b>To study the mutation feature of ganglioside-induced differentiation associated protein-1 (GDAP1) gene in Chinese Charcot-Marie-Tooth disease(CMT) patients.</p><p><b>METHODS</b>Mutation analysis was carried out by use of polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP) combined with DNA direct sequencing of the six exons and their flanking regions of GDAP1 gene in twenty-three CMT patients, including 8 probands of autosomal recessive CMT families and 15 sporadic patients.</p><p><b>RESULTS</b>A compound heterozygous mutation A533G and A767G were unveiled in one autosomal recessive CMT kindred. The homozygous and heterozygous T507G were common SNPs in Chinese population.</p><p><b>CONCLUSION</b>A533G and A767G of GDAP1 gene were new mutations firstly reported.</p>


Asunto(s)
Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Masculino , Enfermedad de Charcot-Marie-Tooth , Genética , Mutación , Proteínas del Tejido Nervioso , Genética , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Análisis de Secuencia de ADN
15.
Chinese Journal of Medical Genetics ; (6): 392-394, 2004.
Artículo en Chino | WPRIM | ID: wpr-328868

RESUMEN

<p><b>OBJECTIVE</b>This study was conducted on a patient with ring-chromosome 13 syndrome and the results were presented and comparatively analyzed with reference to the related literature so as to detect the correlation between chromosome 13 band and the phenotype.</p><p><b>METHODS</b>In this study the authors used G-banding, C-banding, N-banding, high-resolution banding, phenotype location analysis, and a comparative review of literature.</p><p><b>RESULTS</b>It was found that karyotypes of the patient's parents are normal. The patient's karyotype is 45, XX, -13/46, XX, r(13)/46, XX, r(13;13)/47, XX, 2r(13) (p13q32.3). The typical syndrome of ring-chromosome 13 is related to the deletion of 13q34; the deletion of 13q32-13q32.2 is related to hand and foot abnormality, heart murmur, renal defect, skeletal abnormality and external genital abnormality; the deletion of 13q32.3-13q33 is related to micrognathia; 13q22-13q32 is related to atresia, and 13q13-q22 is related to anencephaly.</p><p><b>CONCLUSION</b>It is confirmed that a new breakage-reunion point of ring-chromosome is located at 13p13 and 13q32.3. The variety of clinical characteristics and phenotypes in patients with ring-chromosome 13 syndrome are closely related to the differences of the deletion of chromosome 13.</p>


Asunto(s)
Humanos , Lactante , Masculino , Aberraciones Cromosómicas , Bandeo Cromosómico , Trastornos de los Cromosomas , Diagnóstico , Genética , Cromosomas Humanos Par 13 , Genética , Cariotipificación , Fenotipo , Literatura de Revisión como Asunto , Cromosomas en Anillo
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