ABSTRACT
Objective The purpose of this study was to identify a pathogenic variant in a Chinese family with Alport syndrome and analyze the pathogenicity of the variant. Methods Using targeted region capture and high-throughput sequencing technology, we identified the genetic variant of the proband with Alport syndrome, verified the variant in the family members by Sanger sequencing, and analyzed its influence on the pre-mRNA splicing process by in vitro minigene assay. Results A heterozygous variant c.2767G>T (p.Gly923Cys) was identified as a novel variant in exon 32 of the COL4A5 gene in the proband, which was confirmed by Sanger sequencing to be cosegregated with disease in the family. The minigene assay demonstrated that the c.2767G>T variant induced deletion of exon 32 of the COL4A5 gene. Conclusion A novel COL4A5 mutation was identified by targeted region capture and high-throughput sequencing, which has enriched the gene mutation spectrum of Alport syndrome. The exonic mutation c.2767G>T confirmed to be a splicing mutation by in vitro minigene assay, which may lead to a deeper insight into the molecular pathogenesis of Alport syndrome.
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<p><b>OBJECTIVE</b>This study aimed to determine the effect of recasting in vacuum with argon on the chemical composition of cobalt-chromium (Co-Cr), commercially pure titanium (cpTi), palladium-based (Pd-based), and aurum-platinum (Au- Pt) ceramic alloys.</p><p><b>METHODS</b>Without adding new alloys, Co-Cr, cpTi, Pd-based, and Au-Pt ceramic alloys were recast one to three times under the condition of vacuum compressive casting with argon. Before recasting, four previously cast ceramic alloys were treated with the corresponding method. After polishing, the chemical composition of the four ceramic alloys recasted one to three times were determined by energy-dispersive spectrometry.</p><p><b>RESULTS</b>No significant difference was observed in the chemical composition of the four ceramic alloys recast 1-3 times (P>0.05).</p><p><b>CONCLUSIONS</b>Under the condition of vacuum with argon, the recasting had no obvious influence on the chemical composition of Co-Cr, cpTi, Pd-based, and Au-Pt ceramic alloys.</p>
ABSTRACT
High-throughput sequencing was performed for the peripheral blood DNA from two probands in the family with tuberous sclerosis complex (TSC) to determine the sequences of TSC-related genes TSC1 and TSC2 and their splicing regions and identify mutation sites. Amplification primers were designed for the mutation sites and polymerase chain reaction and Sanger sequencing were used to verify the sequences of peripheral blood DNA from the probands and their parents. The two probands had c.3981-3982 insA (p.Asp1327AspfsX87) and c.4013-4014 delCA (p.Ser1338Cysfs) heterozygous mutations, respectively, in the TSC2 gene. The parents of proband 1 had no abnormalities at these two loci; the mother of proband 2 had c.4013-4014 delCA heterozygous mutation in the TSC2 gene, while the father and the grandparents of proband 2 had no abnormalities. c.3981-3982 insA mutation may cause early coding termination of amino acid sequence at the 1413th site, and c.4013-4014 delCA mutation may cause early coding termination of amino acid sequence at the 1412th site. These two mutations are the pathogenic mutations for families 1 and 2, respectively, and both of them are novel frameshift mutations, but their association with the disease needs to be further verified by mutant protein function cell model and animal model.
Subject(s)
Child , Child, Preschool , Female , Humans , Frameshift Mutation , Tuberous Sclerosis , Genetics , Tumor Suppressor Proteins , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To study gene mutations in four pedigrees with methymalonic aciduria, as well as the feasibility of prenatal diagnosis of methymalonic aciduria.</p><p><b>METHODS</b>High-throughput sequencing was performed for related genes in the peripheral blood of children or parents who were diagnosed with methymalonic aciduria to identify the loci with mutations. Then amplification primers were designed for each locus, and PCR and direct sequencing were performed to validate the sequencing in the first generation in the four pedigrees. Whether the mutations were pathogenic were determined with reference to literature review and medical history. In the pedigrees 1, 3, and 4, ultrasound-guided chorionic villi biopsy was performed at weeks 11-13 of pregnancy to perform early prenatal diagnosis.</p><p><b>RESULTS</b>In pedigree 1, c.656A>T and c.729-730insTT heterozygous mutations in the MUT gene were detected in the proband's father and mother, respectively. Early prenatal diagnosis showed c.656A>T and c.729-730insTT double heterozygous mutations in the fetus. The couple decided to terminate pregnancy. In pedigree 2, c.1106G>A and c.755-756insA double heterozygous mutations in the MUT gene were detected in the proband. c.1106G>A came from the father and c.755-756insA came from the mother. In pedigree 3, c.217C>T and c.609G>A double heterozygous mutations in the MMACHC gene were detected in the proband. c.217C>T came from the father and c.609G>A came from the mother. Prenatal diagnosis showed c.609G>A heterozygous mutation in the fetus. The baby was successfully delivered, and the result of umbilical cord blood testing was consistent with the prenatal diagnosis. In pedigree 4, c.609G>A and c.567dupT double heterozygous mutations in the MMACHC gene were detected in the proband. c.609G>A came from the father and c.567dupT came from the mother. Prenatal diagnosis showed c.567dupT heterozygous mutation in the fetus. The baby was successfully delivered, and the result of umbilical cord blood testing was consistent with the prenatal diagnosis.</p><p><b>CONCLUSIONS</b>Identification of gene mutations helps with prenatal diagnosis in pedigrees with methymalonic aciduria.</p>
Subject(s)
Female , Humans , Male , Amino Acid Metabolism, Inborn Errors , Diagnosis , Genetics , DNA Mutational Analysis , Mutation , Pedigree , Prenatal DiagnosisABSTRACT
Williams-Beuren syndrome is a common chromosome microdeletion syndrome. Early diagnosis and treatment are very helpful for patients and their families. This study identified the chromosome karyotype in one fetus with ultrasonography abnormalities and three children with developmental disorders from four families. This provided guidance for subsequent pregnancy and prenatal diagnosis by using routine G-banding chromosome karyotyping analysis, multiplex ligation-dependent probe amplification (MLPA) and array comparative genomic hybridization (array-CGH). In one amniotic fluid sample from a pregnant woman with fetal abnormalities on an ultrasound screen and three peripheral blood samples from three children with developmental disorders, the decreased signal of ELN gene probes at 7q11.23 and heterozygous deletions at 7q11.23 were detected by MLPA and array-CGH analysis. The laboratory genetic tests of amniotic fluid samples were normal when the mothers from the four families became pregnant again. It was concluded that MLPA and array-CGH are rapid and accurate tools for the diagnosis of Williams-Beuren syndrome and can provide more information for clinical genetic counseling.
Subject(s)
Adult , Child , Child, Preschool , Female , Humans , Pregnancy , Comparative Genomic Hybridization , Multiplex Polymerase Chain Reaction , Prenatal Diagnosis , Williams Syndrome , Diagnosis , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To diagnose a new born baby with 2q37 deletion syndrome by comprehensive use of cytogenetic and molecular techniques and to investigate the phenotype characteristics and applicability of array-comparative genomic hybridization (array-CGH) and multiplex ligation-dependent probe amplification (MLPA) for detection of this syndrome.</p><p><b>METHOD</b>Following conventional chromosome preparation, G banded karyotyping was performed.Genomic DNA was extracted using standard procedures, which were then analyzed by array-CGH and MLPA.</p><p><b>RESULT</b>The patient presented with a typical face, special fist posture and congenital heart disease in 2q37 deletion syndrome. A 4.709 Mb deletion at 2q37.3 (chr2:237, 967, 852-242, 677, 269.NCBI36/hg18, including genes from COL6A3 toPDCD1) was detected by array-CGH. The results of MLPA and G banded karyotyping confirmed the existence of this deletion.</p><p><b>CONCLUSION</b>2q37.3 deletion was determined to be the cryptic cause of this case.2q37 deletion syndrome has some clinically recognizable characteristics. And array-CGH is a powerful technique for the accurate diagnosis and genotype-phenotype correlation study of this syndrome.</p>
Subject(s)
Female , Humans , Infant, Newborn , Abnormalities, Multiple , Genetics , Chromosome Deletion , Chromosomes, Human, Pair 2 , Genetics , Comparative Genomic Hybridization , Genetic Association Studies , Karyotyping , Multiplex Polymerase Chain Reaction , Phenotype , Translocation, GeneticABSTRACT
<p><b>OBJECTIVE</b>To evaluate idic(Yp) in genetic diagnosis by examining 1 infertile man and 1 prenatal fetus using cytogenetic and molecular techniques.</p><p><b>METHODS</b>Following conventional chromosome preparation, we performed G- and C-banding karyo. typing and fluorescence in situ hybridization (FISH). Then we extracted genomic DNA using standard procedures and analyzed it by array-CGH and multiplex ligation-dependent probe amplification (MLPA).</p><p><b>RESULTS</b>Both cases were diagnosed as 45, X/46, X, idic (Yp11.31) mosaicism. The man showed 2 intact copies of Yp11.31-q12 (chrY:2, 710, 250-57, 428, 567, SRY, ZFY, UTY and AZF), and the prenatal fetus exhibited similar findings except a paternal deletion in the AZFc region.</p><p><b>CONCLUSION</b>idic(Y) (p11.31) causes short stature and male infertility. Array-CGH and MLPA can improve the accuracy of the diagnosis of 45, X/46, X, idic (Y) mosaicism, which may contribute to the studies of the phenotype-genotype correlation and clinical genetic counseling.</p>
Subject(s)
Adult , Humans , Male , Chromosomes, Human, Y , Fetus , Infertility, Male , Diagnosis , Genetics , Karyotyping , Microarray Analysis , Mosaicism , Sequence DeletionABSTRACT
<p><b>OBJECTIVE</b>To confirm the diagnosis of a Wolf-Hirschhorn syndrome by family study using both cytogenetic and molecular genetic techniques.</p><p><b>METHOD</b>G-band karyotyping was performed for all the 6 members in the family. Multiplex ligation-dependent probe amplification (MLPA) was used to detect the chromosome abnormality for the proband, his father and brother. Microarray comparative genomic hybridization (Array-CGH) was carried out to map the exact chromosomal breakpoints for the proband.</p><p><b>RESULT</b>The proband presented with a typical face, delayed growth and hypotonia in Wolf-Hirschhorn syndrome. His G-band karyotype was 46, XY, der(4)t(4;8) (p16.2; p23.1)pat. MLPA showed 4pter loss and 8pter gain. Array-CGH revealed an XY male with a 3.781 Mb deletion of 4p16.3-p16.2 and a 6.760 Mb duplication of 8p23.3-p23.1. The proband's brother has mental retardation and skeletal abnormalities. His G-band karyotype was 46, XY, der(8)t(4;8)(p16.2;p23.1)pat. MLPA showed 4pter gain and 8pter loss. The proband's father had normal phenotype with a balanced translocation of 46, XY, t(4;8)(p16.2;p23.1)pat. MLPA showed a normal result. The proband's grandfather showed a normal phenotype with a balanced translocation 46, XY, t(4;8)(p16.2;p23.1). The other members in the family showed normal phenotypes with normal karyotypes.</p><p><b>CONCLUSION</b>The proband has features of Wolf-Hirschhorn syndrome with partial monosomy 4p and partial trisomy 8p. The proband's brother has a partial trisomy 4p and partial monosomy 8p. The derived chromosomes are inherited from paternal balanced translocation t(4;8)(p16.2;p23.1).</p>
Subject(s)
Adult , Female , Humans , Infant , Male , Abnormalities, Multiple , Genetics , Chromosome Deletion , Chromosomes, Human, Pair 4 , Genetics , Chromosomes, Human, Pair 8 , Genetics , Comparative Genomic Hybridization , Karyotyping , Multiplex Polymerase Chain Reaction , Methods , Oligonucleotide Array Sequence Analysis , Pedigree , Phenotype , Translocation, Genetic , Trisomy , Wolf-Hirschhorn Syndrome , Diagnosis , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To explore the necessity of large-scale screening of mitochondria DNA (mtDNA) A1555G mutation for prevention of aminoglycoside antibiotic induced deafness in newborns.</p><p><b>METHODS</b>One thousand blood filter samples were collected from neonates born in July 2008 in Shenzhen. DNA was extracted with Chelex-100 Resin and amplified by PCR. The mtDNA A1555G mutation was determined by denaturing high-performance liquid chromatography(DHPLC) for PCR products. The positive frequency was calculated.</p><p><b>RESULTS</b>The mitochondrial DNA A1555G mutation was detected in 2 cases of 1000 neonates. The frequency of mutation was 0.2%.</p><p><b>CONCLUSION</b>There is a high frequency of mtDNA A1555G mutation in neonates, the large-scale screening of mtDNAA1555G mutation in newborns might detect the individuals sensitive to aminoglycoside antibiotic, which is helpful to guide a rational medication for newborns and the maternal relatives at high-risk. Furthermore, it might be useful to prevent aminoglycoside antibiotic induced deafness.</p>
Subject(s)
Female , Humans , Infant, Newborn , Male , Base Sequence , DNA Mutational Analysis , Methods , DNA, Mitochondrial , Genetics , Polymerase Chain ReactionABSTRACT
<p><b>OBJECTIVE</b>To identify the mutation of human androgen receptor gene (AR) in a patient with complete androgen insensitivity syndrome (CAIS).</p><p><b>METHODS</b>DNA sequences of 8 exons and their exon/intron boundaries of the AR gene in the patient were amplified by PCR and directly sequenced.</p><p><b>RESULTS</b>DNA sequencing revealed a nonsense mutation in exon 1, resulting in a change of codon 441 GAA (glutamic acid) to a stop codon (TAA).</p><p><b>CONCLUSION</b>A novel mutation Glu441stop (GAA to TAA) of the androgen receptor gene leading to complete androgen insensitivity syndrome was identified in this study in a Chinese patient. It may help us further understanding the pathogenesis of CAIS.</p>
Subject(s)
Adult , Humans , Male , Androgen-Insensitivity Syndrome , Genetics , Base Sequence , Molecular Sequence Data , Mutation , Polymerase Chain Reaction , Methods , Receptors, Androgen , Genetics , Sequence Analysis, DNA , MethodsABSTRACT
<p><b>OBJECTIVE</b>To identify potential mutation in the MLC1 gene in a Chinese family affected with megalencephalic leukoencephalopathy and subcortical cysts (MLC), and to provide prenatal diagnosis.</p><p><b>METHODS</b>Genomic DNA of the patients, their parents and younger sister were extracted from peripheral blood. That of the fetus was extracted from an amniotic fluid sample. A total of 12 exons and at least 100 bp flanking the intronic sequence of the MLC1 gene were amplified with PCR. MLC1 mutations were screened by sequencing. Linkage analysis was performed for the family to assure accuracy of prenatal diagnosis.</p><p><b>RESULTS</b>The two patients were both heterozygote for c.177_178delG (p.Ser60AlafsX5) mutation in exon 2 and c.598-2A>C change in intron 7. The c.177_178delG mutation was inherited from the father, and the c.598-2A>C mutation was inherited from the mother. The younger sister and the fetus have both inherited c.177_178delG from the father but did not inherit c.598-2A>C from the mother. Prenatal diagnosis suggested the fetus to be a carrier for a MLC1 mutation. Linkage analysis was consistent with the result of mutation detection. The fetus was born normal as predicted.</p><p><b>CONCLUSION</b>The c.598-2A>C is a novel splicing mutation. Prenatal diagnosis through DNA sequencing and linkage analysis were performed for the first time on Chinese patients with MLC.</p>
Subject(s)
Adolescent , Female , Humans , Male , Pregnancy , Base Sequence , Brain , Pathology , Cysts , Diagnosis , Genetics , DNA Mutational Analysis , Exons , Genetic Linkage , Genetic Testing , Hereditary Central Nervous System Demyelinating Diseases , Diagnosis , Genetics , Magnetic Resonance Imaging , Membrane Proteins , Genetics , Pedigree , Prenatal DiagnosisABSTRACT
<p><b>OBJECTIVE</b>To study the mechanical properties of Co-Cr ceramic alloy after recasts.</p><p><b>METHODS</b>Co-Cr ceramic alloy cast samples were prepared and recast for 3 times without adding any new Co-Cr ceramic alloy. The tensile strength, 0.2% yield strength, percentage of elongation, flexural strength, flexural modulus and Vickers hardness of each specimen were measured.</p><p><b>RESULTS</b>Being cast for different times, the Co-Cr ceramic alloy showed no significant differences on their tensile strength, 0.2% yield strength, percentage of elongation, flexural strength, flexural modulus and Vickers hardness.</p><p><b>CONCLUSION</b>Co-Cr ceramic alloy can be recast for 3 times at least, without decrease of the mechanical properties.</p>
Subject(s)
Alloys , Ceramics , Chromium Alloys , Dental Stress Analysis , Hardness , Materials Testing , Metal Ceramic Alloys , Tensile StrengthABSTRACT
<p><b>OBJECTIVE</b>To conduct molecular and prenatal diagnosis for a couple with β thalassemia.</p><p><b>METHODS</b>Blood routine examination and hemoglobin analysis were used for screening of thalassemia. Seventeen common Chinese mutations of β thalassemia were detected for the carriers with β thalassemia using PCR/RDB. The unknown mutation of β thalassemia was identified by DNA sequencing and DHPLC analysis.</p><p><b>RESULTS</b>The husband was heterozygote of CD41/42 (-TCTT). The wife carried a mutation IVS-I-110 (G→A) of β thalassemia having not been reported in Chinese so far. The fetus was a double mutated heterozygote of IVS-I-110 (G→A) and CD41/42 (-TCTT). The pregnancy was terminated.</p><p><b>CONCLUSION</b>Mutation IVS-I-110 (G→A) of β thalassemia in Chinese is of importance to the genetic counseling and prenatal diagnosis of thalassemia.</p>
Subject(s)
Female , Humans , Male , Pregnancy , Base Sequence , DNA Mutational Analysis , Mutation , Pregnancy Complications, Hematologic , Genetics , Prenatal Diagnosis , beta-Thalassemia , Diagnosis , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To investigate the change of retentive forces of cast cobalt-chromium (Co-Cr) alloy clasp in cyclic fatigue test.</p><p><b>METHODS</b>Samples of three types of cast Co-Cr alloy (Group A: Hardalloy; B: Regalloy™; C: Vera PDN™) clasps were fabricated and placed at undercut depths of 0.25 mm, 0.50 mm. The clasps were drawn from the model molar cyclicly to simulate 5 years of clinical use in an universal testing machine. Retentive force were record at 21 different time point for each clasp during the whole fatigue testing process. Data were subjected to ANOVA, Chi-square test and linear regression analysis.</p><p><b>RESULTS</b>All clasps showed decreasing retention during the cyclic fatigue test. Clasps engaged in 0.50 mm undercut depth exhibited greater initial retentive force [Group A: (8.714 +/- 1.104) N, B: (9.072 +/- 0.653) N, C: (9.588 +/- 1.980) N] as well as greater loss of retention [Group A: (4.408 +/- 0.662) N, B: (3.484 +/- 0.494) N, C: (3.290 +/- 1.484) N] at the end of the test than clasps engaged in 0.25 mm undercut did [initial forces were (7.940 +/- 0.357), (7.834 +/- 1.308) and (8.156 +/- 1.067) N for Group A, B, C, respectively; loss of retention were (2.444 +/- 0.736) N, (2.954 +/- 1.048) N and (1.832 +/- 1.180) N for group A, B, C, respectively]. Negative correlation was found between the clasp retention and the logarithm of cycling times.</p><p><b>CONCLUSIONS</b>Co-Cr alloy cast clasp could provide adequate retentive force for 5 years of clinical use.</p>
Subject(s)
Chromium Alloys , Chemistry , Dental Alloys , Chemistry , Dental Casting Technique , Dental Clasps , Dental Stress Analysis , Denture RetentionABSTRACT
<p><b>OBJECTIVE</b>To evaluate the possible association of the MTHFR C677T polymorphism with genetic susceptibility to hepatocellular carcinoma (HCC) in a Chinese population.</p><p><b>METHODS</b>Five hundred and eight HCC cases and 543 controls were studied. The MTHFR genotypes were determined using a PCR-based restriction fragment length polymorphism (RFLP) method. Odds ratios (ORs) for HCC and 95% confidence intervals (CIs) from unconditional logistic regression models were used to evaluate relative risks. Potential HCC risk factors were included in the logistic regression models as covariates in the multivariate analyses on genotypes and HCC risks.</p><p><b>RESULTS</b>No overall significant difference in genotype distribution was found when comparing all HCC cases to controls (P = 0.258). However, a significantly increased risk of HCC was observed among T/T homozygotes (adjusted OR = 1.66, 95% CI = 1.08-2.54, P<0.05) compared to C-allele carriers (CC or CT). When stratified with sex, this trend was more prominent in females, but not in males. Females who were homozygous (T/T) for the C677T polymorphism were at a 2.64-fold (95% CI = 1.19-5.88, P<0.05) increased risk of developing HCC when compared to C-allele carriers. However in males, T/T homozygotes had a similar risk with C-allele carriers.</p><p><b>CONCLUSION</b>The MTHFR C677T polymorphism may be associated with a higher HCC risk in females, but not in males in this population.</p>
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Carcinoma, Hepatocellular , Genetics , Genetic Predisposition to Disease , Liver Neoplasms , Genetics , Logistic Models , Methylenetetrahydrofolate Reductase (NADPH2) , Genetics , Polymorphism, GeneticABSTRACT
<p><b>OBJECTIVE</b>To investigate gene mutations of a consanguineous family with two oculocutaneous albinism (OCA) patients.</p><p><b>METHODS</b>Genomic DNA was prepared from peripheral leukocytes. All of the exons and flanking introns of P gene and TYR gene were PCR-direct-sequenced. Hha I restriction fragment length polymorphism in codon 787 of the P gene was studied in the family and 102 unrelated normal Chinese individuals.</p><p><b>RESULTS</b>Although no mutations were found in TYR gene, a missense mutation A787T was found in P gene. Two patients of the family were both homozygous for A787T. Their parents and brother were heterozygous for the mutation. The mutation was not observed among 102 normally pigmented subjects.</p><p><b>CONCLUSION</b>The A787T mutation is not a common polymorphism among normal Chinese and it seems most likely to be a pathological OCA2 mutation. This is the first report on the study of gene diagnosis in Chinese OCA2 patients.</p>
Subject(s)
Adult , Female , Humans , Male , Albinism, Oculocutaneous , Ethnology , Genetics , Amino Acid Sequence , Asian People , Genetics , Base Sequence , China , Codon , Consanguinity , DNA Mutational Analysis , Exons , Homozygote , Introns , Membrane Transport Proteins , Genetics , Molecular Sequence Data , Monophenol Monooxygenase , Genetics , Mutation, Missense , Pedigree , Sequence Homology, Nucleic AcidABSTRACT
<p><b>OBJECTIVE</b>A functional single nucleotide polymorphism (SNP) at codon 72 of the gene for p53 protein (p53 R72P) has been implicated in a variety of human cancers, but the relationship between this SNP and hepatocellular carcinoma (HCC) remains obscure despite the fact that the critical role of p53 protein in HCC has been documented. This study was conducted to evaluate the link between the polymorphism with HCC stratified by chronic hepatitis B infection status in a Chinese population.</p><p><b>METHODS</b>Four hundred and sixty-nine HCC cases (359 HbsAg-positive, 110 HbsAg-negative) and 567 controls (137 HbsAg-positive, 430 HbsAg-negative) were studied. The p53 genotypes were determined by a PCR based restriction fragment length polymorphism (RFLP) method.</p><p><b>RESULTS</b>Overall, no correlation between HCC and the R72P genotypes was found when comparing all cases to controls or when comparing the HbsAg-positive HCC subgroup to controls. However, in HbsAg-negative subjects, the 72P allele was significantly associated with the presence of HCC (P=0.01) and had a higher risk (OR=1.69, 95% CI: 1.25-2.27) of HCC as compared to the 72R allele. By comparison to R/R homozygotes, the R/P heterozygotes and P/P homozygotes had a 1.73-fold (95% CI: 0.96-3.11) and a 3.29-fold (95% CI: 1.58-6.86) increased risk for HCC, respectively. The subjects with the 72P allele and a family history of HCC and those with the 72P allele and male gender also yielded an 11.14-fold (95% CI: 1.62-76.67) and a 9.39 fold (95% CI: 3.08-28.62) increased risk of HCC, respectively.</p><p><b>CONCLUSION</b>The P allele of the p53 R72P polymorphism has an increased risk for HCC in HbsAg-negative subjects, and exerts a synergistic influence on the risk for HCC when combined with HCC family history and the male gender.</p>
Subject(s)
Female , Humans , Male , Asian People , Genetics , Carcinoma, Hepatocellular , Ethnology , Genetics , China , Codon , Genetics , Gene Frequency , Genetic Predisposition to Disease , Genetics , Genotype , Linkage Disequilibrium , Liver Neoplasms , Ethnology , Genetics , Polymerase Chain Reaction , Polymorphism, Single Nucleotide , Tumor Suppressor Protein p53 , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To investigate the role of loss of heterozygosity (LOH) in tumor suppressor genes (TSG) and microsatellite instability (MSI) in hepatocarcinogenesis, as well as their correlation with clinicopathologic features.</p><p><b>METHODS</b>LOH in 6 TSG (APC, DCC, MCC, OGG1, p53 and RB1) was detected in 36 informative cases of hepatocellular carcinoma (HCC), among 92 surgically resected HCC. Thirteen polymorphic microsatellite markers were also studied in 15 of these cases by microdissection-based PCR amplification and direct DNA sequencing. The correlation between genetic alterations and clinicopathologic features was analyzed.</p><p><b>RESULTS</b>The overall incidence of LOH in HCC was 41.7% (15/36). There was no LOH in MCC gene. 46.2% (6/13) microsatellites showed LOH in 9 of the 15 cases of HCC (60%). Certain clinicopathologic differences were observed between cases (number = 7) with LOH in APC, OGG1 and DCC ("type I") and cases (number = 8) with LOH in p53 and RB1 ("type II"). The mean tumor size of these two types was 2.9 (+/- 1.7) cm and 7.2 (+/- 3.4) cm, respectively (P < 0.01); and the mean survival was 72.0 (+/- 38.6) months, and 51.0 (+/- 30.4) months, respectively (P < 0.05).</p><p><b>CONCLUSIONS</b>Compared with MSI pathway, LOH pathway plays a more important role in the development of HCC. A multistep hepatocarcinogenesis is likely, with LOH in APC, OGG1 and DCC ("type I") being an early event and LOH in p53 and RB1 ("type II") being a late event. On the other hand, MCC gene seems to play no role in the whole process.</p>
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Infant , Male , Middle Aged , Carcinoma, Hepatocellular , Genetics , Pathology , Genes, APC , Genes, DCC , Genes, MCC , Genes, Tumor Suppressor , Genes, p53 , Liver Neoplasms , Genetics , Pathology , Loss of Heterozygosity , Microsatellite InstabilityABSTRACT
<p><b>OBJECTIVE</b>To study the clinicopathological characteristics, immunohistochemical features and differential diagnosis of hepatic angiomyolipoma (AML).</p><p><b>METHODS</b>The clinicopathological features of hepatic AML were systematically examined in 44 surgically resected tumor specimens, with additional immunohistochemistry study using 10 relevant antibodies.</p><p><b>RESULTS</b>The tumors were composed of various amounts of three components, i.e. blood vessels, smooth muscle cells and adipose cells. According to the proportions of each of these tissue components, AML was subcategorized into the classical type (n = 13), myomatous type (n = 25), lipomatous type (n = 4), and angiomatous type (n = 2). Myoid cells displayed various morphology, including epithelioid, intermediate (ovoid or short spindle), spindle, oncocytic, and pleomorphic features. Hematopoietic elements were present as minor findings in eight tumors. Immunohistochemically, the tumor cells were strongly positive for HMB45 (44/44, 100%), SMA (38/38, 100%) and CD117 (30/38, 78.9%).</p><p><b>CONCLUSIONS</b>A correct diagnosis of hepatic AML might be difficult due to its various growth patterns and cell types. HMB-45 positivity in the myoid cells is a key feature for hepatic AML. CD117 may be another useful ancillary marker for reaching a definite diagnosis.</p>
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Angiomyolipoma , Classification , Allergy and Immunology , Pathology , Antigens, Neoplasm , Biomarkers, Tumor , Diagnosis, Differential , Follow-Up Studies , Immunohistochemistry , Liver , Pathology , Liver Neoplasms , Classification , Allergy and Immunology , Pathology , Melanoma-Specific Antigens , Neoplasm Proteins , Proto-Oncogene Proteins c-kitABSTRACT
<p><b>OBJECTIVE</b>To investigate the elastic limit and relevant enclasp force of the non-precious metal casting clasp.</p><p><b>METHODS</b>Casting clasp samples of five cobalt-chromium alloys and one 18 - 8 nickel-chromium alloy were made from prefabricated clasp wax by invesing, casting, sandblasting, and ultrasonic cleaning. The process of casting clasp samples deflected by loading and returned by unloading was tested and electric signals were collected by an omnipotent material machine. The analog electric signal was converted to digital signal by an analog to digital converter and stored in a computer. The elastic limit and the relevant enclasp force were analyzed using a relative software.</p><p><b>RESULTS</b>The elastic limit and the relevant enclasp force of the casting clasp made from the 18 - 8 nickel-chromium alloy were smallest and those of the clasps made from the cobalt-chromium alloys in various brands were different. The range of the elastic limit of the cobalt-chromium alloy casting clasp with the length of 5.0 mm in undercut was 0.28 mm-0.33 mm and the relevant enclasp force was 14.42 g-19.28 g.</p><p><b>CONCLUSIONS</b>In clinic, we should select the suitable undercut deepness wherein the cobalt-chromium alloy casting clasps, according to different brands of the casting alloy, undercut length, undercut slope, and the clasp thickness.</p>