The Wound Healing of Autologous Regenerative Factor on Recurrent Benign Airway Stenosis: A Canine Experimental and Pilot Study.

INTRODUCTION: Benign airway stenosis (BAS) is a severe pathologic condition. Complex stenosis has a high recurrence rate and requires repeated bronchoscopic interventions for achieving optimal control, leading to recurrent BAS (RBAS) due to intraluminal granulation. METHODS: This study explored the potential of autologous regenerative factor (ARF) for treating RBAS using a post-intubation tracheal stenosis canine model. Bronchoscopic follow-ups were conducted, and RNA-seq analysis of airway tissue was performed. A clinical study was also initiated involving 17 patients with recurrent airway stenosis. RESULTS: In the animal model, ARF demonstrated significant effectiveness in preventing further collapse of the injured airway, maintaining airway patency and promoting tissue regeneration. RNA-seq results showed differential gene expression, signifying alterations in cellular components and signaling pathways. The clinical study found that ARF treatment was well-tolerated by patients with no severe adverse events requiring hospitalization. ARF treatment yielded a high response rate, especially for post-intubation tracheal stenosis and idiopathic tracheal stenosis patients. CONCLUSION: The study concludes that ARF presents a promising, effective, and less-invasive method for treating RBAS. ARF has shown potential in prolonging the intermittent period and reducing treatment failure in patients with recurrent tracheal stenosis by facilitating tracheal mucosal wound repair and ameliorating tracheal fibrosis. This novel approach could significantly impact future clinical applications.

Inheritance and innovation of the diagnosis of peripheral pulmonary lesions.

As the leading cause of cancer-related deaths worldwide, early detection and diagnosis are crucial to reduce the mortality of lung cancer. To date, the diagnosis of the peripheral pulmonary lesions (PPLs) remains a major unmet clinical need. The urgency of diagnosing PPLs has driven a series of development of the advanced bronchoscopy-guided techniques in the past decades, such as radial probe-endobronchial ultrasonography (RP-EBUS), virtual bronchoscopy navigation (VBN), electromagnetic navigation bronchoscopy (ENB), bronchoscopic transparenchymal nodule access (BTPNA), and robotic-assisted bronchoscopy. However, these techniques also have their own limitations. In this review, we would like to introduce the development of diagnostic techniques for PPLs, with a special focus on biopsy approaches and advanced guided bronchoscopy techniques by discussing their advantages, limitations, and future prospects.

Loss-of-function mutations in TDRD7 lead to a rare novel syndrome combining congenital cataract and nonobstructive azoospermia in humans.

PURPOSE: Comorbid familial nonobstructive azoospermia (NOA) and congenital cataract (CC) have not been reported previously, and no single human gene has been associated with both diseases in humans. Our purpose was to uncover novel human mutations and genes causing familial NOA and CC. METHODS: We performed whole-exome sequencing for two brothers with both NOA and CC from a consanguineous family. Mutation screening of TDRD7 was performed in another similar consanguineous family and 176 patients with azoospermia or CC alone and 520 healthy controls. Histological analysis was performed for the biopsied testicle sample in one patient, and knockout mice were constructed to verify the phenotype of the mutation in TDRD7. RESULTS: Two novel loss-of-function mutations (c.324_325insA (T110Nfs*30) and c.688_689insA (p.Y230X), respectively) of TDRD7 were found in the affected patients from the two unrelated consanguineous families. Histological analysis demonstrated a lack of mature sperm in the male patient's seminiferous tubules. The mutations were not detected in patients with CC or NOA alone. Mice with Tdrd7 gene disrupted at a similar position precisely replicated the human syndrome. CONCLUSION: We identified TDRD7 causing CC as a new pathogenic gene for male azoospermia in human, with an autosomal recessive mode of inheritance.

Novel mutations of PKD genes in Chinese patients suffering from autosomal dominant polycystic kidney disease and seeking assisted reproduction.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD), the commonest inherited kidney disease, is generally caused by heterozygous mutations in PKD1, PKD2, or GANAB (PKD3). METHODS: We performed mutational analyses of PKD genes to identify causative mutations. A set of 90 unrelated families with ADPKD were subjected to mutational analyses of PKD genes. Genes were analysed using long-range PCR (LR-PCR), direct PCR sequencing, followed by multiplex ligation-dependent probe amplification (MLPA) or screening of GANAB for some patients. Semen quality was assessed for 46 male patients, and the correlation between mutations and male infertility was analysed. RESULTS: A total of 76 mutations, including 38 novel mutations, were identified in 77 families, comprising 72 mutations in PKD1 and 4 in PKD2, with a positive detection rate of 85.6%. No pathogenic mutations of GANAB were detected. Thirty-seven patients had low semen quality and were likely to be infertile. No association was detected between PKD1 mutation type and semen quality. However, male patients carrying a pathogenic mutation in the Ig-like repeat domain of PKD1 had a high risk of infertility. CONCLUSION: Our study identified a group of novel mutations in PKD genes, which enrich the PKD mutation spectrum and might help clinicians to make precise diagnoses, thereby allowing better family planning and genetic counselling. Men with ADPKD accompanied by infertility should consider intracytoplasmic sperm injection combined with preimplantation genetic diagnosis to achieve paternity and obtain healthy progeny.

Novel FOXL2 mutations cause blepharophimosis-ptosis-epicanthus inversus syndrome with premature ovarian insufficiency.

BACKGROUND: Blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) is a malformation of the eyelids. Forkhead Box L2 (FOXL2) is the only gene known to be associated with BPES. METHODS: We identified two Han Chinese BPES families with premature ovarian insufficiency (POI). Sanger sequencing and in vitro functional analysis were performed to identify the genetic cause. RESULTS: Sanger sequencing identified two novel mutations (c.462_468del, c.988_989insG) in FOXL2, one in each family. The in vitro functional analysis confirmed that both novel mutations were associated with impaired transactivation of downstream genes. Specifically, the single-base insertion, c.988_989insG, led to subcellular mislocalization and aggregation of the encoded protein, which validated the hypothesis that the two novel FOXL2 mutations are deleterious and associated with POI in the two BPES families. CONCLUSION: The novel mutations identified in the present study will enhance the present knowledge of the mutation spectrum of FOXL2. The in vitro experiments provide further insights into the molecular mechanism by which the two new variants mediate disease pathogenesis and may contribute to elucidating the genotype-phenotype correlation between the two novel FOXL2 mutations and POI.

DMC1 mutation that causes human non-obstructive azoospermia and premature ovarian insufficiency identified by whole-exome sequencing.

BACKGROUND: The genetic causes of the majority of male and female infertility caused by human non-obstructive azoospermia (NOA) and premature ovarian insufficiency (POI) with meiotic arrest are unknown. OBJECTIVE: To identify the genetic cause of NOA and POI in two affected members from a consanguineous Chinese family. METHODS: We performed whole-exome sequencing of DNA from both affected patients. The identified candidate causative gene was further verified by Sanger sequencing for pedigree analysis in this family. In silico analysis was performed to functionally characterise the mutation, and histological analysis was performed using the biopsied testicle sample from the male patient with NOA. RESULTS: We identified a novel homozygous missense mutation (NM_007068.3: c.106G>A, p.Asp36Asn) in DMC1, which cosegregated with NOA and POI phenotypes in this family. The identified missense mutation resulted in the substitution of a conserved aspartic residue with asparaginate in the modified H3TH motif of DMC1. This substitution results in protein misfolding. Histological analysis demonstrated a lack of spermatozoa in the male patient's seminiferous tubules. Immunohistochemistry using a testis biopsy sample from the male patient showed that spermatogenesis was blocked at the zygotene stage during meiotic prophase I. CONCLUSIONS: To the best of our knowledge, this is the first report identifying DMC1 as the causative gene for human NOA and POI. Furthermore, our pedigree analysis shows an autosomal recessive mode of inheritance for NOA and POI caused by DMC1 in this family.

[Analysis of FOXL2 gene mutations in 5 families affected with blepharophimosis, ptosis and epicanthus inversus syndrome].

OBJECTIVE: To screen for FOXL2 gene mutations in 6 patients with blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES), and explore their genotype-phenotype correlation. METHODS: Peripheral venous blood samples were collected from the patients for the extraction of genomic DNA. PCR and Sanger sequencing were employed to analyze the coding region and flanking sequences of the FOXL2 gene. Pathogenicity of the identified mutations was verified through literature review and bioinformatic analysis. RESULTS: A heterozygous c.672_701dup30 mutation was found in the probands from the two familial cases, while three heterozygous mutations (two were novel), namely c.462_468del (p.Pro156Argfs*113), c.251T to A (p.Ile84Asn) and c.988_989insG (p.Ala330Glyfs*204) were detected in the three sporadic cases. Literature review and bioinformatic analysis indicated that all these mutations are pathogenic. CONCLUSION: Identification of causative mutations in the BPES patients has provided a basis for genetic counseling and reproductive guidance. The novel mutations have enriched the mutation spectrum of the FOXL2 gene.

[Karyotyping and analysis of 5α -reductase-2 gene mutation in 25 patients with hypospadias].

OBJECTIVE: To analyze the karyotypes and SRD5A2 gene mutations in 25 patients with sporadic or familial hypospadias. METHODS: The patients included 10 adults and 15 children, whose chromosomes were analyzed by G-banded karyotyping, and the SRD5A2 genes were sequenced. RESULTS: Two patients were found to have an abnormal karyotype, while eight have carried compound heterozygous mutations of the SRD5A2 gene, which included 5 genotypes formed by 6 types of mutations, i.e., p.G203S/p.R227Q, p.R227Q/p.R246Q, p.Q6X/p.Q71X, p.L20P/p.G203S, and p.Q71X/p.R227Q. Mutations of the SRD5A2 gene were present in 32% (8/25) of all patients, 35% (8/23) in those with a normal karyotype, and 44.4% (8/18) in those with proximal type hypospadia. Bioinformatic analysis, literature review and pedigree analysis confirmed that all such mutations are pathogenic. CONCLUSION: Chromosomal anomalies and mutations of the SRD5A2 gene are the main cause of hypospadias. Sequencing of the SRD5A2 gene may explain the etiology of nearly half of the patients with proximal type of hypospadas but a normal karyotype, which can facilitate genetic consulting.

[Study of a Bethlem myopathy pedigree resulted from a novel mutation of COL6A3 gene].

OBJECTIVE: To determine the molecular etiology for a muscular dystrophy pedigree with target region sequencing platform using hereditary myopathy capture array. METHODS: Specific gene testing was performed based on the clinical diagnosis. Since no pathogenic mutation was found, target region sequencing with hereditary myopathy capture array combined with Sanger sequencing and bioinformatics analysis were employed in turn. PolyPhen and NCBI were used to evaluate the pathogenicity of identified mutation and conservation of the gene. RESULTS: Target region sequencing indicated the proband has carried a heterozygous c.3353 A>C mutation of COL6A3 gene, which was confirmed by Sanger-sequencing in 4 affected individuals from the family. The same mutation was not detected in healthy members of the pedigree. Bioinformatics analysis suggested that the mutation has caused a highly pathogenic amino acid substitution from Histidine to Proline. The affected patients featured normal intelligence with mild myogenic damage by muscle biopsy, slightly increased serum creatine kinase and slow disease progression, which was consistent with Bethlem myopathy. CONCLUSION: Target region sequencing is an effective and efficient method for genetic testing. The heterozygous c.3353A>C mutation in exon 8 of the COL6A3 gene probably underlies the Bethlem myopathy with autosomal dominant inheritance.

The first patient with a pure 1p36 microtriplication associated with severe clinical phenotypes.

BACKGROUND: Copy Number Variants (CNVs) is a new molecular frontier in clinical genetics. CNVs in 1p36 are usually pathogenic and have attracted the attention of cytogeneticists worldwide. None of 1p36 triplication has been reported thus far. RESULTS: We present three patients with CNVs in 1p36. Among them one is the first 1p36 tetrasomy due to a pure microtriplication and the other two are 1p36 microdeletion. Traditional chromosome G-banding technique showed a normal karyotype. Single nucleotide polymorphism (SNP) microarray analysis combined with multiplex ligation-dependent probe amplification (MLPA) and fluorescence in situ hybridization (FISH) were used to identify and confirm the chromosome microdeletion/microtriplication. The facial dysmorphisms of the patient with 1p36 tetrasomy differed from those two patients with 1p36 monosomy. The expression levels of B3GALT6, MIB2, PEX10 and PANK4 in the blood were determined, and differential expressions were observed between the patients and controls. CONCLUSIONS: Our study shows the first case of 1p36 tetrasomy due to a pure microtriplication in a patient with severe intellectual disability and seizures. The study provides a new resource for studying the mechanisms of microtriplication formation, and provides an evidence that overexpression of the specific genes might be related the specific phenotype of 1p36 microtriplication.

[Mutation screening and prenatal diagnosis of tuberous sclerosis complex].

OBJECTIVE: To screen mutations of tuberous sclerosis complex (TSC) patients to confirm a clinical diagnosis of TSC, and to perform prenatal diagnosis for families with mutations. METHODS: In this study, PCR-denaturing high-performance liquid chromatography(DHPLC), supplemented with sequencing when necessary, was used to screen TSC1 and TSC2 mutations in 21 patients from 19 pedigrees visited author's hospital in the last five years. For novel mutations, one hundred unrelated healthy individuals were screened to exclude the possibility of polymorphism. RESULTS: Seventeen different mutations were found in 21 patients of 19 pedigrees with 13 being novel mutations, including c. 2672delA, c. 2672insA of TSC1 gene and c.4918insCGCC, c.1143delG, Intron27+1 G>A, c.1957-1958delAG, Intron5+1 G>A, c.910insCT, c.2753 C>G, c.4078dupAGCAAGTCCAGCTCCTC, Intron 11 -1 G>A, Intron 14+1 G>A, c.684 C>A of TSC2 gene, indicating a high frequency of de novo mutations in TSC. Three of these mutations were in the TSC1 gene (N762S, c.2672insA and c. 2672delA), while all remaining 14 were in the TSC2 gene. Prenatal diagnosis for TSC was performed for 7 fetuses from these pedigrees. The six fetuses that tested negative for TSC mutations were carried to term and, to date, none of these children has shown symptoms of TSC. CONCLUSION: Author's data showed that a mutation detection rate of tuberous sclerosis was 89.5%(17/19) among patients in author's hospital. The ratio of TSC2 and TSC1 mutations was about 1:1 in the familial cases, but TSC2 mutation was more common than TSC1 mutation in sporadic cases. Author's data demonstrated that birth of TSC children for those with familial history of TSC could be prevented through prenatal diagnosis.

[Mutation detection of PKD1 gene in patients with autosomal dominant polycystic kidney diseases].

OBJECTIVE: To detect gene mutation in the patients with autosomal dominant polycystic kidney disease (PKD). METHODS: Polymerase chain reaction (PCR)-denaturing high-performance liquid chromatography (DHPLC) analyses were performed in 3o single copy region of PKD 1 gene (PKD1). DNA sequencing were carried out on PCR products with abnormal peak shape afterwards. RESULTS: A new nonsense mutation (C11901A in exon 42 of PKD1 was identified to cause serine in position 3897 turning to a stop codon. A missense mutation, C10737T, was detected in exon 35 which caused threonine in position 3509 turn to methionine. Two kinds of samesense mutation, G11824A and C11860T in exon 42, were found in normal control. CONCLUSION: PKD1 mutation were detected successfully by PCR-DHPLC. A new nonsense mutation, a missense mutation and two polymorphisms are identified in this study.

Molecular cloning and preliminary function study of a novel human gene, TSARG7, related to spermatogenesis.

A novel human gene TSARG7 (GenBank accession No. AY513610) was identified from a human testis cDNA library by using the mTSARG7 gene (GenBank accession No. AY489184) as an electronic probe. The gene whose full cDNA length is 2,463 bp containing 12 exons and 11 introns is located in the human chromosome 8p11.21. The predicted protein encoded by this gene contains 456 amino acids with a theoretical molecular weight of 56,295 dalton and isoelectric point of 9.13. It is a new member of the acyltransferase family since its sequence possesses the highly conserved PlsC domain existing in all acyltransferase-like proteins. Two groups, the TSARG7 and mTSARG7, the TSARG7 and Au041707, share 97% identity in the 456 amino acids. Expression of the TSARG7 gene is restricted to the testis. Subcellular localization studies show that the EGFP-tagged TSARG7 protein was localized in the cytoplasm of GC-1 cells. The TSARG7 mRNA expression was initiated in the testis of a 13-year-old boy, and its level increased steadily along with spermatogenesis and sexual maturation of the human. The results of heat stress experiment demonstrate that TSARG7 expression has a relation with temperature. In conclusion, our study suggests that we have cloned a novel human gene and this gene may play an important role in human spermatogenesis and sexual maturation.

Molecular cloning of a novel mouse testis-specific spermatogenic cell apoptosis inhibitor gene mTSARG7 as a candidate oncogene.

A novel mouse gene, mTSARG7 (GenBank accession No. AY489184), with a full cDNA length of 2279 bp and containing 12 exons and 11 introns, was cloned from a mouse expressed sequence tag (GenBank accession No. BE644543) that was significantly up-regulated in cryptorchidism. The gene was located in mouse chromosome 8A1.3 and encoded a protein containing 403 amino acid residues that was a new member of the acyltransferase family because the sequence contained the highly conserved phosphate acyltransferase (PlsC) domain existing in all acyltransferase-like proteins. The mTSARG7 protein and AU041707 protein shared 83.9% identity in 402 amino acid residues. Expression of the mTSARG7 gene was restricted to the mouse testis. The results of the in situ hybridization analysis revealed that the mTSARG7 mRNA was expressed in mouse spermatogonia and spermatocytes. Subcellular localization studies showed that the EGFP-tagged mTSARG7 protein was localized in the cytoplasm of GC-1 spg cells. The mTSARG7 mRNA expression was initiated in the mouse testis in the second week after birth, and the expression level increased steadily with spermatogenesis and sexual maturation of the mouse. The results of the heat stress experiment showed that the mTSARG7 mRNA expression gradually decreased as the heating duration increased. The pcDNA3.1 Hygro(-)/mTSARG7 plasmid was constructed and introduced into GC-1 spg cells by liposome transfection. The mTSARG7 can accelerate GC-1 spg cells, causing them to traverse the S-phase and enter the G2-phase, compared with the control group where this did not occur as there was no transfection of mTSARG7. In conclusion, our results suggest that this gene may play an important role in spermatogenesis and the development of cryptorchid testes, and is a testis-specific apoptosis candidate oncogene.

[Preliminary exploration of the influence factors on amplification of single cell duplex-nested PCR].

OBJECTIVE: To explore the influence factors on amplification of single cell duplex-nested PCR. METHODS: The mutational loci region CD41-42 and IVS-II 654 of beta-globin gene were amplified by duplex-nested PCR with different combination of primers concentration, different Taq DNA polymerases, different neutralization buffers and with or without predenaturation at 98 degrees C before the PCR amplification in single lymphocyte or single blastomere, thus, to investigate the influence of these factors on the amplification efficiency of PCR. RESULTS: TaKaRa EX Taq was the most efficient Taq DNA polymerase among different Taq DNA polymerases; primer pair R1+F1 at final concentration of 0.25 micromol/L and R2+F2 at 0.3 micromol/L were the most efficient ones in amplification among different combinations of primers concentrations; the amplification efficiency in neutralization buffer-1 (200 mmol/L Tricine) was obviously higher than that of neutralization buffer-2 (900 mmol/L Tris-HCl, pH 8.3/300 mmol/L KCl/200 mmol/L HCl)(P<0.05); there were no remarkable differences of the amplification efficiency while using whether predenaturation at 98 degrees C before the single cell PCR amplification or not (P>0.05). CONCLUSION: There were remarkable differences of the amplification efficiency of single cell duplex-nested PCR while using different combination of primers concentrations, different Taq DNA polymerases, different neutralization buffers. However, predenaturation at 98 degrees C before the single cell PCR amplification could not improve the PCR amplification efficiency.

[Diagnosis of hemophilia A by a combination of St14(DXS52) VNTR polymorphism and (CA)n repeat polymorphism within FVIII gene].

OBJECTIVE: To improve the accuracy and the diagnostic rate of gene diagnosis and prenatal gene diagnosis for hemophilia A (HA) families. METHODS: Linkage analysis was performed by using St14(DXS52) VNTR polymorphism and intron 13 (CA)n repeat polymorphism of the factor VIII gene among HA families for indirect diagnosis. RESULTS: The diagnostic rates using linkage analysis based upon one of the above mentioned two polymorphic loci among 9 HA families were 66.7% and 66.7%, respectively. The diagnostic rate rose to 88.9% by using a combination of the two polymorphic loci. Prenatal gene diagnoses were performed for 4 HA families. A wrong prenatal diagnosis which may happen when linkage analysis was performed by using only St14 VNTR was monitored. CONCLUSION: The rapid and accurate gene diagnosis and prenatal gene diagnosis could be performed by a combination of the two polymorphic loci for about 90% HA families.

[46,XY female sex reversal patient with a novel point mutation in the coding sequence of the SRY gene].

OBJECTIVE: To investigate the molecular mechanism of a Chinese patient with 46, XY sex reversal. METHODS: DNA fragments of the SRY gene from the typical XY female sex reversal patient and her father were amplified by polymerase chain reaction (PCR). The amplified PCR fragments were cloned into the pUCm-T vector, and direct sequencing was carried out on an ABI 377-3 automated DNA sequencer to detect the mutation. PCR-restriction enzyme digestion was applied to detect the results of DNA sequencing. RESULTS: A novel mutation of the SRY gene was identified in the XY sex reversal patient of this study. A T is replaced by an A in codon 129 at position +387, resulting in the replacement of the polar amino acid tyrosine (TAT) by the stop code (TAA) in the HMG-box, whereas her father was proved to have the wild-type sequence. Because the mutation introduced an enzyme site of MaeIII, the PCR-restrict enzyme digestion showed that there were three bands (131 bp,231 bp and 247 bp) in the patient, whereas two bands (131 bp and 478 bp) in normal man. It verified the results of sequencing analysis. The results after searching the Human Gene Mutation Database showed that this mutation was not described before and should be a new mutation. CONCLUSION: The novel mutation in SRY gene has provided valuable information for the understanding of molecular mechanism of the patient with 46,XY female sex reversal.

[Diagnosing achondroplasia by single cell nested-PCR].

OBJECTIVE: To research on the reliability of diagnosing achondroplasia (ACH) on single cell level and to provide a basis for preimplantation genetic diagnosis(PGD). METHODS: The high-frequency mutation region G380R of fibroblast growth factor receptor 3(FGFR3) gene was amplified by nested-PCR with single lymphocyte and single blastomere. The products of PCR were digested by restriction enzyme Bfm I, then the digested products were detected by 10% polyacrylamida gel electrophoresis(PAGE). RESULTS: The amplification success rate, allele dropout rate and correct diagnosis rate of single lymphocyte's PCR were 90.4%, 8.2% and 91.8%,respectively. The amplification success rate of single blastomere was 75.4%. CONCLUSION: The diagnosis of ACH by single cell nested-PCR is comparatively stable and reliable.

[The detection of the frequent mutations of iduronate-2-sulphatase gene in mucopolysaccharidosis type II patients in Chinese].

OBJECTIVE: To investigate and establish the gene diagnosis methods for the frequent mutations of iduronate-2-sulphatase(IDS) gene in mucopolysaccharidosis type II patients. METHODS: polymerase chain- reaction-single strand conformation polymorphism PCR-SSCP) analysis was applied to detect the mutations of exons 3, 8 and 9 which were hot spots in the iduronate-2-sulfatase gene; DNA sequencing was applied to analyze the mutations which had been detected by PCR-SSCP; PCR-restriction fragment length polymorphism (PCR-RFLP) was applied to detect the results of DNA sequencing. RESULTS: Obvious and abnormal bands in exon 9 of the IDS gene were found by applying PCR-SSCP; the mutation(C1672T) of exon 9 was found in the patient through DNA sequencing, which led to amino acid replacement(R468W); the PCR-restriction enzyme digestion showed that only one band(554 bp) appeared in the patient, but there were two bands (257 bp and 297 bp) in his parents, and it verified the results of sequencing analysis. CONCLUSION: PCR-SSCP analysis, DNA sequencing analysis and PCR-restriction enzyme digestion are effective methods for MPS II diagnosis. Combined applications of these methods can verify and complement each other and improve the accuracy of diagnosis.