Metagenomic next-generation sequencing could play a pivotal role in validating the diagnosis of invasive mold disease of the central nervous system.

Background: Invasive mold diseases of the central nervous (CNS IMD) system are exceedingly rare disorders, characterized by nonspecific clinical symptoms. This results in significant diagnostic challenges, often leading to delayed diagnosis and the risk of misdiagnosis for patients. Metagenomic Next-Generation Sequencing (mNGS) holds significant importance for the diagnosis of infectious diseases, especially in the rapid and accurate identification of rare and difficult-to-culture pathogens. Therefore, this study aims to explore the clinical characteristics of invasive mold disease of CNS IMD in children and assess the effectiveness of mNGS technology in diagnosing CNS IMD. Methods: Three pediatric patients diagnosed with Invasive mold disease brain abscess and treated in the Pediatric Intensive Care Unit (PICU) of the First Affiliated Hospital of Zhengzhou University from January 2020 to December 2023 were selected for this study. Results: Case 1, a 6-year-old girl, was admitted to the hospital with "acute liver failure." During her hospital stay, she developed fever, irritability, and seizures. CSF mNGS testing resulted in a negative outcome. Multiple brain abscesses were drained, and Aspergillus fumigatus was detected in pus culture and mNGS. The condition gradually improved after treatment with voriconazole combined with caspofungin. Case 2, a 3-year-old girl, was admitted with "acute B-lymphoblastic leukemia." During induction chemotherapy, she developed fever and seizures. Aspergillus fumigatus was detected in the intracranial abscess fluid by mNGS, and the condition gradually improved after treatment with voriconazole combined with caspofungin, followed by "right-sided brain abscess drainage surgery." Case 3, a 7-year-old girl, showed lethargy, fever, and right-sided limb weakness during the pending chemotherapy period for acute B-lymphoblastic leukemia. Rhizomucor miehei and Rhizomucor pusillus was detected in the cerebrospinal fluid by mNGS. The condition gradually improved after treatment with amphotericin B combined with posaconazole. After a six-month follow-up post-discharge, the three patients improved without residual neurological sequelae, and the primary diseases were in complete remission. Conclusion: The clinical manifestations of CNS IMD lack specificity. Early mNGS can assist in identifying the pathogen, providing a basis for definitive diagnosis. Combined surgical treatment when necessary can help improve prognosis.

[Analysis of ADAR gene variants in a Chinese pedigree affected with Dyschromatosis symmetrica hereditaria in conjunct with developmental delay].

OBJECTIVE: To explore the clinical characteristics and genetic etiology for a Chinese pedigree affected with Dyschromatosis symmetrica hereditaria (DSH) in conjunct with developmental delay. METHODS: A child who had presented at the First Affiliated Hospital of Zhengzhou University on May 28 2021 for abnormal skin pigmentation of the extremities and growth retardation for over 2 years was selected as the study subject. Clinical data of the child and his pedigree (11 individuals from three generations) was collected. The child was subjected to whole exome sequencing, and candidate variant was verified by Sanger sequencing. RESULTS: The child, a two-year-and-seven-month-old male, had hyper- and hypopigmentation on his hands, feet and face, in addition with delayed development. All members of his pedigree had typical presentation of DSH. A heterozygous c.2657G>A variant was found in exon 8 of the ADAR gene in the child, his mother, and elder sister. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted as likely pathogenic (PM1+PM2_Supporting+PP1+PP3). CONCLUSION: The c.2657G>A variant of the ADAR gene probably underlay the DSH in this pedigree.

Neurological function and drug-refractory epilepsy in Sturge-Weber syndrome children: a retrospective analysis.

Epilepsy in Sturge-Weber syndrome (SWS) is common, but drug-refractory epilepsy (DRE) in SWS has rarely been studied in children. We investigated the characteristics of epilepsy and risk factors for DRE in children with SWS. A retrospective study was conducted to analyze the clinical characteristics of children with SWS with epilepsy in our hospital from January 2013 to October 2022. Univariate and multivariate logistic analyses were performed to investigate the factors influencing DRE in children with SWS. A total of 35 SWS children with epilepsy were included (51% male; mean age of presentation 3.6 ± 0.5 years), 71% of children with SWS had their first seizure within the first year of life, and the most common type of seizure was focal seizure (77%). Eleven (31%) patients developed DRE. The median age of onset for the first seizure was 1.0 years and all these cases were of SWS type I. Multivariate logistic analysis revealed that stroke-like episodes and seizure clusters were risk factors for DRE in SWS children. A poor neurological function group was observed in twenty-five children with SWS. Status epilepticus was a risk factor that affected the neurological function of SWS children with epilepsy.  Conclusion: The study explored the epileptic features of children with SWS. The results revealed that stroke-like episodes and seizure clusters are risk factors for DRE in children with SWS. The occurrence of status epilepticus impacts the neurological function of SWS children with epilepsy. Thus, long-term follow-up is necessary to monitor outcomes. What is Known: • Sturge-Weber syndrome (SWS) is a rare neurocutaneous disorder, over 75% of children with SWS experience seizures, and 30-57% develop drug-refractory epilepsy (DRE), which leads to a poor outcome. • Drug-refractory epilepsy in SWS has been rarely studied in children, and the risk factors associated with DRE are unclear. What is New: • Clinical features of SWS children with drug-refractory epilepsy. • In SWS, stroke-like episodes and seizure clusters are risk factors of DRE, the occurrence of status epilepticus impacts the neurological function.

Cell-membrane-coated nanoparticles for the fight against pathogenic bacteria, toxins, and inflammatory cytokines associated with sepsis.

Sepsis is the main cause of death in patients suffering from serious illness. Yet, there is still no specific treatment for sepsis, and management relies on infection control. Cell membrane-coated nanoparticles (MNPs) are a new class of biomimetic nanoparticles based on covering the surface of synthetic nanoparticles (NPs) with natural cell membranes. They retain the physicochemical properties of synthetic nanomaterials and inherit the specific properties of cellular membranes, showing excellent biological compatibility, enhanced biointerfacing capabilities, capacity to hold cellular functions and characteristics, immunological escape, and longer half-life when in circulation. Additionally, they prevent the decomposition of the encapsulated drug and active targeting. Over the years, studies on MNPs have multiplied and a breakthrough has been achieved for cancer therapy. Nevertheless, the use of "bio"-related approaches is still rare for treating sepsis. Herein, we discussed current state-of-the-art on MNPs for the treatment of bacterial sepsis by combining the pathophysiology and therapeutic benefits of sepsis, i.e., pathogenic bacteria, bacteria-producing toxins, and inflammatory cytokines produced in the dysregulated inflammatory response associated with sepsis.

[Analysis of clinical phenotype and genetic variant in a case of familial hemophagocytic lymphohistiocytosis type â ¢].

OBJECTIVE: To explore the genetic basis for a newborn with familial hemophagocytic lymphohistiocytosis type 3 (FHL3). METHODS: Clinical and laboratory data of the newborn and his family members were reviewed. Whole exome sequencing (including and flanking intronic regions) was carried out. Candidate variants were verified by Sanger sequencing. Wild type and mutant minigene vectors containing exon 23, intron 23 and exon 24 of the UNC13D gene were constructed and transfected into HEK293T cells by lipofectamine reagent. Reverse transcription PCR was carried out to verify the splicing of the minigenes. RESULTS: Pedigree analysis and clinical examinations indicated that the child has autosomal recessive FHL3. DNA sequencing revealed that he has harbored c.118-308 (IVS1) C>T and c.2298+1 (IVS23) G>A variants of the UNC13D gene, which were respectively inherited from his father and mother, which constituted compound heterozygosity and were both predicted to be pathogenic. Minigene experiment confirmed that the c.2298+1(IVS23) G>A variant has resulted skipping of exon 23 (-207nt) resulting in a truncated protein. CONCLUSION: The c.118-308(IVS1) C>T and c.2298+1(IVS23) G>A compound heterozygous variants of the UNC13D gene probably underlay the FHL3 in this child, which has resulted in low expression as well as abnormal splicing of UNC13D mRNA.

Overlapping infection of Nocardia farcinica and Aspergillus fumigatus in a child with X-linked chronic granulomatous disease: a case report.

BACKGROUND: Chronic granulomatous disease (CGD) is a rare inherited primary immunodeficiency syndrome, manifested as recurrent infections and inflammatory complications. Although prophylactic treatment with antibiotics and antifungals improved the outcome of CGD patients, infections remain the major cause of mortality. CASE PRESENTATION: A boy aged 3 years and 8 months was admitted to hospital complaining of lip swelling with fever for half a month and neck abscess for 11 days. After a thorough examination, severe pneumonia, respiratory failure, oral and maxillofacial space infection, and perianal abscess were confirmed. However, his condition didn't improve after initial comprehensive therapy. Subsequently, overlapping infections of Nocardia farcinica and Aspergillus fumigatus were identified by metagenomic next-generation sequencing. He was treated with imipenem, linezolid, and voriconazole intravenously, plus taking oral compound sulfamethoxazole. Later, his condition improved. Through whole-exome sequencing, the child was ultimately diagnosed as X-linked chronic granulomatous disease (X-CGD) caused by CYBB gene mutation. Allogeneic hematopoietic stem cell transplantation was the potential sanative approach but there were no available human leukocyte antigen compatible donors for the child. The family requested to transfer to a superior hospital for further treatment. Two months later, we followed up the child's family. Unfortunately, the child had expired due to severe infection. CONCLUSION: To our knowledge, this is the first case of overlapping infection of Nocardia farcinica and Aspergillus fumigatus identified by metagenomic next-generation sequencing in a child with X-CGD from China. For infectious pathogens that are hard to diagnosis by traditional detection methods, metagenomic next-generation sequencing is recommended as an adminicle or indispensable approach for microbial identification. Patients with X-CGD have poor prognosis, early diagnosis and intervention of X-CGD may reduce the mortality.

miR-141-3p inhibits the activation of astrocytes and the release of inflammatory cytokines in bacterial meningitis through down-regulating HMGB1.

BACKGROUND: Bacterial meningitis (BM) is a serious infectious disease of the central nervous system that often occurs in children and adolescents. Many studies have suggested that microRNAs (miRNAs) are involved in BM. This study aimed to address the effects of miR-141-3p on astrocyte activation and inflammatory response in BM through HMGB1. METHODS: The 3-week-old rats were injected with Streptococcus pneumoniae (SP) into the lateral ventricle to establish a BM model. Loeffler scoring method was used to evaluate the recovery of neurological function. Brain pathological damage was observed by hematoxylin and eosin (H&E) staining. Primary astrocytes were isolated from brain tissues of BM or non-infected SD rats. The levels of TNF-α, IL-1ß, and IL-6 in brain tissues and astrocyte culture supernatant were measured by enzyme-linked immunosorbent assay (ELISA). The targeting relationship between miR-141-3p and HMGB1 was tested using dual-luciferase reporter assay. The expression of miR-141-3p, HMGB1, and the astrocytic marker glial fibrillary acidic protein (GFAP) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blotting. Methylation-specific PCR (MSP) analysis was performed to measure the methylation status of miR-141 promoter. RESULTS: The results showed that lower Loeffler scores were exhibited in rats with BM. The subarachnoid space of brain tissues of BM rats was widened, and obvious inflammatory cells were observed. miR-141-3p expression was reduced in BM rats and SP-treated astrocytes. Additionally, we found that overexpression of miR-141-3p led to the downregulation of HMGB1, GFAP, and inflammatory cytokines (TNF-α, IL-1ß, and IL-6) in astrocytes. Furthermore, the results of dual-luciferase reporter assay confirmed that miR-141-3p directly targeted HMGB1. Overexpression of miR-141-3p inhibited the levels of GFAP, TNF-α, IL-1ß, and IL-6 in astrocytes, which was eliminated by the up-regulation of HMGB1. The results of MSP analysis indicated that miR-141 promoter was highly methylated in brain tissues and astrocytes. DNMT1 was involved in the methylation of miR-141 promoter in BM. CONCLUSION: The present study verified that miR-141-3p affected inflammatory response by suppressing HMGB1 in SP-induced astrocytes and BM rat model.

Starch and castor oil mutually modified, cross-linked polyurethane for improving the controlled release of urea.

Due to the poor controlled release ability, bio-based materials are difficult for large scale application on controlled release fertilizers (CRFs). Starch-based polyol (SP) and castor oil (CO) were mutually modified, and a cross-linked polymer film was formed on the surface of urea by in-situ reaction, which improved the slow release ability of the bio-based material. The results showed that increasing the CO ratio reduced porosity of coating and prolonged the nitrogen (N) release period, while the SP changed the high-temperature wrinkle characteristics and regulated the early N release rate. The mutual modification achieved an ultra-long release period of bio-based CRUs for 7 months. The degradation rate during nine months of bio-based coatings (5.05 %) was significantly higher than that of petroleum-based (3.74 %), and the coating was non-toxic to rice seeds. Mutual modification provided a safe and effective solution for the preparation of bio-based CRFs with long-term controlled release capability.

Silencing of long non-coding RNA DLX6-AS1 weakens neuroblastoma progression by the miR-513c-5p/PLK4 axis.

Emerging evidence has demonstrated the crucial roles of long noncoding RNAs in human cancers, including neuroblastoma (NB). DLX6 antisense RNA 1 (DLX6-AS1) has been identified as an oncogenic driver in NB. However, the mechanisms of DLX6-AS1 in NB progression are not fully understood. Our data showed that DLX6-AS1 was significantly overexpressed in NB tissues and cells. Moreover, DLX6-AS1 silencing repressed NB cell viability, colony formation, migration, and invasion, and promoted cell cycle arrest and apoptosis in vitro, as well as decreased tumor growth in vivo. Mechanistically, DLX6-AS1 operated as a miR-513c-5p sponge. MiR-513c-5p mediated the regulation of DLX6-AS1 on NB cell malignant progression in vitro. PLK4 was a target of miR-513c-5p- and DLX6-AS1-controlled PLK4 expression via sponging miR-513c-5p. Furthermore, the suppressive effect of miR-513c-5p overexpression on NB cell malignant progression in vitro was reversed by PLK4 upregulation. Our findings identified a novel regulatory mechanism, the DLX6-AS1/miR-513c-5p/PLK4 axis, in NB progression, highlighting a strong rationale for developing DLX6-AS1 as a new target for NB management.

Water Polishing improved controlled-release characteristics and fertilizer efficiency of castor oil-based polyurethane coated diammonium phosphate.

The production cost of controlled-release fertilizers is an important factoring limiting their applications. To reduce the coating cost of diammonium phosphate (DAP) and improve its nutrition release characteristics, the fertilizer cores were modified by water polishing with three dosages at 1, 2, and 3%. The effects of modification were evaluated in terms of particle hardness, size distribution, angle of repose and specific surface area. Castor oil-based polyurethane was used as coating material for fertilizer performance evaluation. A pot experiment was conducted to verify the fertilizer efficiency of coated diammonium phosphate (CDAP) with maize. The results showed that polishing with 2% water reduced the angle of repose by 2.48-10.57% and specific surface area by 5.70-48.76%, making it more suitable for coating. The nutrient release period of CDAP was significantly prolonged by 5.36 times. Soil available phosphorous, enzyme activities, maize grain yield, and phosphorous use efficiency were all improved through the blending application of coated and normal phosphate fertilizer. This study demonstrated that water-based surface modification is a low-cost and effective method for improvement and promotion of controlled release P fertilizers.

Association of TP53 rs1042522 C>G and miR-34b/c rs4938723 T>C polymorphisms with hepatoblastoma susceptibility: A seven-center case-control study.

BACKGROUND: Hepatoblastoma is a rare malignancy originating from pluripotent stem cells with unknown etiology. An understanding of the etiology in pediatric hepatoblastoma has been hampered by the unavailability of sufficient patient samples. To date, only a few epidemiological studies with small sample sizes have been performed investigating risk factors for hepatoblastoma. TP53 and pri-miR-34b/c genes are implicated in the tumorigenesis, yet the role of their polymorphisms in hepatoblastoma susceptibility remains unknown. METHODS: We conducted a seven-center case-control study to explore the genetic variants predisposing to hepatoblastoma susceptibility. In our study, we genotyped two functional polymorphisms, the TP53 rs1042522 C>G (Arg72Pro) and miR-34b/c rs4938723 T>C, in 313 cases and 1446 controls using the TaqMan method. RESULTS: Single loci analysis showed that neither TP53 rs1042522 C>G, nor miR-34b/c rs4938723 T>C significantly modified hepatoblastoma risk. In the stratification analysis, we identified that the miR-34b/c rs4938723 TC/CC genotypes were associated with a decreased risk in patients with clinical stages III + IV hepatoblastoma (adjusted odds ratio = 0.53, 95% confidence interval = 0.33-0.84, P=0.007] compared to the rs4938723 TT genotype. Subsequent analysis further showed that the combination of TP53 and miR-34b/c variant genotypes had no impact on susceptibility hepatoblastoma. CONCLUSIONS: Taken together, TP53 rs1042522 C>G and miR-34b/c rs4938723 T>C may not confer hepatoblastoma susceptibility. These findings may aid in our understanding of the genetic etiology of hepatoblastoma.

Selective targeting of MAPK family kinases JNK over p38 by rationally designed peptides as potential therapeutics for neurological disorders and epilepsy.

Human mitogen-activated protein kinase (MAPK) family members JNK and p38 are two homologous protein-serine/threonine kinases but play distinct roles in the pathological process of neurological disorders. Selective targeting of JNK over p38 has been established as a potential therapeutic approach to epilepsy and other nervous system diseases. Herein, we describe an integrated in vitro-in silico protocol to rationally design kinase-peptide interaction specificity based on crystal structure data. In the procedure, a simulated annealing (SA) iteration optimization strategy is described to improve peptide selectivity between the two kinases. The optimization accepts moderate compromise in peptide affinity to JNK in order to maximize the affinity difference between peptide interactions with JNK and p38. The structural basis, energetic properties and dynamic behavior of SA-improved peptides bound with the peptide-docking sites of JNK and p38 kinase domains are investigated in detail using atomistic molecular dynamics (MD) simulations and post binding free energy analysis. The theoretical findings and computational designs are then confirmed by fluorescence polarization assays. Using the integrated protocol we successfully obtain three decapeptide ligands, namely RLHPSMTDFL, RAKLPTSVDY and KPSRPWNLEI, that exhibit both potent affinity to JNK (K = 8.0, 5.4 and 12.1 µM, respectively) and high selectivity for JNK over p38 (K/K = 9.2, 17.9 and 6.3 fold, respectively). We also demonstrate that a JNK-over-p38 selective peptide should have a positively charged N-terminus, a polar central region and a negatively charged C-terminus, in which a number of hydrophobic residues distribute randomly along the peptide sequence. In particular, the residue positions 1, 6 and 9 play a crucial role in shaping peptide selectivity; the presence of, respectively, Arg, Thr and Asp at the three positions confers high specificity to kinase-peptide interactions.

A case of late-onset riboflavin responsive multiple acyl-CoA dehydrogenase deficiency (MADD) with a novel mutation in ETFDH gene.

We report a novel mutation in the electron transfer flavoprotein dehydrogenase (EFTDH) gene in an adolescent Chinese patient with late-onset riboflavin-responsive multiple acyl-CoA dehydrogenase deficiency (MADD) characterized by muscle weakness as early symptom. At the age of 9 years, the patient experienced progressive muscle weakness. Blood creatine kinase level and aminotransferase were higher than normal. The muscle biopsy revealed lipid storage myopathy. Serum acylcarnitine and urine organic acid analyses were consistent with MADD. Genetic mutation analysis revealed a compound heterozygous mutation in EFTDH gene. The patients showed good response to riboflavin and l-carnitine treatment.

[Early prenatal diagnosis for a family affected with X-linked spondyloepiphyseal dysplasia tarda family].

OBJECTIVE: X-linked spondyloepiphyseal dysplasia tarda (SEDL) is a rare osteochondrodysplasia caused by mutations of SEDL gene, which usually onset in late childhood without systemic complications. In this study, we have provided prenatal diagnosis for an affected family with a combined strategy including direct sequencing, fetal-sex identification and microsatellite linkage analysis. METHODS: Two amniotic fluid samples from carrier gravida and 7 blood samples from individuals in this SEDL pedigree were obtained. Genomic DNA was extracted from the samples using standard phenol-chloroform method. SRY and AMEL genes were employed to assess fetal sex. Microsatellite DXS16 was genotyped for linkage analysis. A pathogenic mutation of the SEDL gene was identified by bi-directionally direct sequencing of the third exon as well as its exon/intron boundaries. RESULTS: Two male fetuses were confirmed by fetal-sex assessment. The mutation of the SEDL gene was identified as a nucleotide substitution of the splice acceptor site in intron 2, IVS2-2A>C. DNA sequencing indicated that one fetus is hemizygote carrying the mutation, whilst another is not a carrier. Linkage analysis was identical with the sequencing results. Follow-up also confirmed the result of prenatal diagnosis. CONCLUSION: Fetal-sex assessment combined with microsatellite linkage analysis and bi-directionally direct sequencing is a more accurate and ready strategy for prenatal diagnosis of families affected with SEDL.

[Hydroa vacciniforme-like cutaneous T cell lymphoma: a case report and literature review].

OBJECTIVE: To study the clinical features, diagnosis and therapy of hydroa vacciniforme-like cutaneous T cell lymphoma. METHODS: The clinical presentations and the findings of laboratory examinations and skin biopsy of affected tissue in a child with hydroa vacciniforme-like cutaneous T cell lymphoma were retrospectively reviewed. RESULTS: The child manifested as rash, fever and lymph node intumesce. Rash was pantomorphia, including edematous erythema, vesicles, crusts, necrosis and depressed scar, and it was mild in winter and severe in summer, mainly involving in the face and extremities. Epstein-Barre virus (EBV)-IgM was positive. Histopathological findings revealed focal lymphocyte invasion in subcutaneous panniculus adiposus, mainly surrounding the blood vessels. Immunohistochemistry showed CD3 (+), CD43 (+), CD20 (-), pax-5 (-), TIA (+), CD5 (+), CD8 (+), Granmye (+) and CD4 (-). The clinical symptoms were improved after glucocorticoid treatment in this child. CONCLUSIONS: Hydroa vacciniforme-like cutaneous T cell lymphoma has special clinical manifestations. This disorder may be definitely diagnosed by skin biopsy of affected tissue and immunohistochemistry assay. Glucocorticoid treatment is effective. EBV infection may be related to the development of this disorder.

[Effect of a novel splicing mutation (IVS2-2A-->C) of SEDL gene on RNA processing].

X-linked spondyloepiphyseal dysplasia tarda (SEDL) is a rare osteochondrodysplasia caused by the mutation of SEDL gene, which mainly involves vertebral bodies and hips. To explore the effect of the novel splicing mutation (IVS2 -2A-->C) of SEDL gene on mRNA processing in a large Chinese family with X-linked spondyloepiphyseal dysplasia tarda and to elucidate the molecular base of SEDL, total RNA was isolated from EDTA blood samples of patients and controls. RT-PCR was performed on total RNA. cDNA was analyzed by bi-directionally direct sequencing of PCR products and Polyacrylamide gel electrophoresis (PAGE). Sequencing analysis revealed that there were two kinds of cDNA in patients. One is that exon 2 directly spliced exon 4, that is, exon 3 absence from the mature mRNA; and the other is that exon 1 directly spliced exon 4, meaning both exon 2 and 3 being spliced out completely. Meanwhile one kind of cDNA that exon 1 directly spliced exon 3 was found in normal controls. By PAGE, RT-PCR amplified products, 679bp and 537bp, were detected in normal controls, while 567bp and 425bp fragments were found in affected individuals. Our data show that the mutation of the splice-acceptor site in intron 2 causes exon 3 entirely exclusion from the mature RNA transcripts in affected individuals. As the translation start site of the SEDL gene locates on exon 3, the splicing defect causes affected individuals failure to produce sedlin, which elucidates the causative role of SEDL gene in the pathogenesis of SEDL. The absence of exon 2 indicates that there is alternative splicing in SEDL gene. The alternative splicing was also found in normal controls, which demonstrated that the alternative splicing might not be related to the phenotype of SEDL. Because the alternative splicing of exon 2 occurred in the 5'UTR, it is not clear whether it affects the gene expression.

[Clinical study of 83 cases with spinal muscular atrophy in children].

OBJECTIVE: Spinal muscular atrophy (SMA) is a common autosomal recessive disorder and represents one of the most common genetic causes of death in childhood. The last 10 years have seen major advances in the field of SMA, but no curative treatment is available so far. This study aimed to analyze the clinical characteristics of SMA, improve the clinical diagnosis of SMA, and explore the importance of gene diagnosis and prenatal diagnosis of SMA by gene deletion analysis. METHODS: Totally 83 cases with SMA including 55 males and 28 females were enrolled in this study. The age was between 1 day and 14 years (average 23.7 months). The clinical characteristics and changes of electromyography were assessed in all cases. The muscular biopsy was performed in 2 of 83 cases. The deletion of survival of motor neuron gene (SMN) was detected by PCR and restriction endonuclease spectrum analysis in 13 of 83 cases. RESULTS: The 83 cases were subdivided into three clinical groups based on age of onset of symptom, age at death and achievement of certain motor milestone, 60 cases with type I, 19 cases with type II and 4 cases with type III. They were all characterized by symmetric muscle weakness (more proximal than distal) associated with atrophy, absence or marked decrease of deep tendon reflexes. Electromyographic studies showed a pattern of denervation with neither sensory involvement nor marked decrease of motor nerve conduction velocities in all cases. Muscle biopsy provided evidence of skeletal muscle denervation with groups of atrophy in 2 cases. The SMN detection revealed deletion of exon 7 and exon 8 in 11 of 13 cases, only lacking exon 7 in 1 of 13 cases and lacking exon 8 in 1 of 13 cases. CONCLUSION: SMA is characterized by degeneration of lower motor neuron associated with muscle paralysis and atrophy. The definite diagnosis of SMA will rely on the typical clinical characteristics, changes of electromyogram and muscle biopsy and gene deletion analysis. Gene diagnosis of SMA can provide a basis for prenatal diagnosis which is of great importance in preventing SMA.

[Identification of a novel mutation IVS2-2A-->C of SEDL gene in a Chinese family with X-linked spondyloepiphyseal dysplasia tarda].

OBJECTIVE: To identify the mutation of spondyloepiphyseal dysplasia tarda (SEDL) gene in a large Chinese family with X-linked spondyloepiphyseal dysplasia tarda and to make a discussion on the pathogenesis of SEDL at the molecular level. METHODS: In two patients, four exons comprising the SEDL open reading frame as well as their exon/intron boundaries were analyzed by bi-directional direct sequencing of PCR products. The sequencing results were compared against the normal sequences in GenBank to find the mutation. Then the mutation was identified in other members of the family. RESULTS: A nucleotide substitution of the splice acceptor in SEDL intron 2, IVS2 -2A-->C,was detected in two affected individuals (IV(15) V(3)) in the Chinese family with SEDL, but no sequence change occurring on exons 3-6 was detected. The transversion was also identified in four heterozygous carriers. The mutation was not found in two unaffected male individuals and fifteen normal controls. Furthermore, four potential carriers were identified in the family. CONCLUSION: The mutation IVS2 -2A-->C of SEDL gene was firstly determined in the world. The change of the splice acceptor in SEDL intron 2 may cause skipping of exon 3 which is responsible for the disease. Molecular diagnosis can be made by detecting the mutation.

[Gene diagnosis of X-linked spondyloepiphyseal dysplasia tarda by linkage analysis and DNA sequencing].

OBJECTIVE: X linked spondyloepiphyseal dysplasia tarda (SEDL) is heritable osteochondrondysplasia characterized in affected males by disproportional short stature with short neck and trunk resulting from a growth defect of the vertebral bodies, accompanied by barrel chest and degenerative osteoarthropathy of hip joints. This progressive skeletal dysplasia is caused by the SEDL gene located approximately 100 kb centromeric of DXS16 at Xp22. The disorder usually manifests in late childhood without systemic complications, and generally female carriers of SEDL are asymptomatic. So the diagnosis of potential carriers and presymptomatic patients is almost impossible. This study aimed to establish methods of gene diagnosis for finding out potential carriers and presymptomatic patients. METHODS: The blood samples were collected from 21 individuals in a large Chinese pedigree with SEDL. Microsatellite marker DXS16 was selected for linkage analysis. In order to confirm the allele of DXS16 linked to the pathogenic SEDL gene, polymerase chain reaction (PCR) and polyacrylamide gel electrophoresis (PAGE) were used to examine the variability of the lengths of DXS16, and linkage analysis was performed for the diagnosis of potential carriers and presymptomatic patients. Then the pathogenic mutation of the SEDL gene in the family was identified by bi-directionally direct sequencing of PCR products amplified for each of the four coding exons as well as their exon/intron boundaries. The potential carriers and presymptomatic patients were also diagnosed in this way. RESULTS: Six young individuals (IV(14), IV(19), IV(21), IV(23), V(4), V(7))who wanted to know whether they were carriers or presymptomatic patients were diagnosed by linkage analysis. Four females of them (IV(14), IV(19), IV(21), V(7)) were determined being carriers because they carry the allele of DXS16 which links the pathogenic SEDL gene, and the other two (IV(23), V(4)) being normal individuals for their alleles of DXS16 linked with wild SEDL gene. DNA sequencing identified that the pathogenic mutation of SEDL gene in the family, which was a nucleotide substitution of the splice-acceptor site in intron 2, IVS2 -2 A-->C. This is a novel mutation in the SEDL gene. Four female individuals (IV(14), IV(19), IV(21), V(7)) carried the mutation; individuals IV(23) and V(4) carried the wild SEDL gene. The results of diagnosis of linkage analysis coincide completely with that of DNA sequencing. CONCLUSION: Linkage analysis is a simple, rapid and inexpensive gene diagnosis method for SEDL and its accuracy was the same as DNA sequencing. Each of linkage analysis and DNA sequencing can be used to diagnose SEDL, which is very helpful for finding potential carriers and presymptomatic patients.