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For studying the changing rules of the tribological properties and the related mechanisms of ta-C film in friction against several typical counterpart materials，a ta-C film with a thickness of approximately 1 μm was deposited by the laser-induced arc magnetic filtered vacuum cathode arc technology，and three kinds of counterpart balls with high hardness (WC，Al2O3 and 9Cr18) were used for friction and wear test.The microstructure and tribological properties of the ta-C film were systematically investigated by scanning electron microscopy，X-ray photoelectron spectroscopy，Raman spectrometer，surface profilometer，nano-indentation tester and ball-disk friction and wear equipment.Results showed that the ta-C film possessed extremely low friction coefficients in friction against all the three counterpart materials，and exhibited excellent antiwear and antifriction properties.When Al2O3 counterpart was employed，the friction coefficient of the film was the lowest with a value of around 0.11；when 9Cr18 counterpart was employed，the film showed the lowest wear rate of 4.0×10-7 mm3/(N·m)；and when WC counterpart was employed，the film showed the highest wear rate of 7.6×10-7 mm3/(N·m). Besides，the main wear mechanism of the film was abrasive wear，and a graphitized transfer film with the characteristics of carbon structure was detected on the surfaces of all the counterparts.

Patients with bilateral vertebral artery occlusion have a high incidence of cerebral infarction with poor prognosis. Infarction of bilateral middle cerebellar peduncle (MCP) is extremely rare and only a few cases have been reported in literature. A 74-year-old male patient was admitted to our hospital with a chief complaint of dizziness and walking instability for 13 d. Brain magnetic resonance image showed acute bilateral middle cerebellar peduncle infarction. Digital subtraction angiography showed occlusion of the initiation part of left vertebral artery and whole right vertebral artery, while a large amount of collateral circulations and recanalization were observed. After volume expansion, anti-platelet aggregation and lipid-lowering therapy, the symptoms disappeared. The patient was followed up for 10 months and he recovered well.

Objective: To construct wild-type and mutant pEGFP SPAST vectors and to explore the molecular mechanism of hereditary spastic paraplegia., Methods: Mutant SPAST vector was constructed using overlap PCR method following construction of wild-type SPAST vector. Wild-type and mutant constructs were transfected to COS7 cells and subcellular localization of spastin was observed. Co-localizations of spastin and microtubule, spastin and mitochondria were viewed by immunofluorescence staining., Results: Wild-type spastin is localized in plasma, and mutant spastin did not change its cellular localization. Wild-type and mutant spastins did not co-localize with microtubules and mitochondria by immunofluorescence analysis., Conclusion: Wild-type and mutant SPAST constructs were successfully generated. Mutant spastin did not change its localization in cells. Spastin does not co-localize with microtubules and mitochondria. This study may facilitate further studies on molecular mechanism of hereditary spastic paraplegia.

Objective: To review the clinical and genetic features of a pedigree of Kennedy disease in China., Methods: The clinical data of patients from a Kennedy disease family were collected. The numbers of trinucleotide CAG repeats in exon 1 of the androgen receptor gene were determined by DNA sequencing and repeat fragment analysis., Results: In the pedigree, 4 patients were identified as Kennedy disease. Clinical manifested with adult-onset, progressive proximal limb muscle weakness and atrophy, gynecomastia, oligospermia were also presented. The number of trinucleotide CAG repeats in exon 1 of the androgen receptor gene was 51 in the proband. The electrophysiological study showed sensory and motor involvement and their serum triglycerides values were elevated significantly., Conclusion: Androgen receptors gene testing is the most reliable diagnosing method, the patients suspected as Kennedy disease should have a gene testing of androgen receptors.

We investigated the clinical features and gene mutation in a pedigree of spinocerebellar ataxia (SCA). A series of clinical tests was performed including visual examination, retinal angiography, visual evoked potential, electroretinogram and magnetic resonance imaging. Genomic DNA of the family members and normal controls was used for amplification of the (CAG)n repeats of SCA1, SCA2, SCA3, SCA6, SCA7, SCA17 and DRPLA genes by PCR. The number of (CAG)n was determined by 8% denaturing polyacrylamide gel electrophoresis and direct sequencing. The main features of 2 patients were ataxia, visual failure, retinal degeneration, cerebellar and pontine atrophy. A mutation in SCA7 gene was detected, while no mutations were found in SCA1, SCA2, SCA3, SCA6, SCA17 or DRPLA gene. Therefore, this is a pedigree of SCA7. Analysis of the CAG trinucleotide repeat expansion at the SCA7 locus can provide valuable insights into SCA7.

We report the clinical and pathological features of two pedigrees of palmoplantar keratoderma (PPK), the expression of keratin 9 (K9) in palm tissue and the mutation of the keratin 9 gene (KRT9). Histopathology and immunohistochemical assessment was performed to analyze the epidermis in the palm of the probands. Genomic DNA of 46 family individuals was used for amplification of exon 1 of KRT9. The mutations were determined by direct sequencing. Epidermal abnormalities in the palm of the two probands were characterized by vacuolar changes of suprabasal keratinocytes accompanied by thickening of the living epidermis and stratum corneum. K9 was also expressed in particular epithelial tissues. Direct sequencing of polymerase chain reaction products revealed heterozygous missense mutations in exon 1 of KRT9 (N160S and L167S) in the two families, respectively. N160S and L167S of KRT9 are disease-causing mutations in these two Chinese pedigrees with epidermolytic palmoplanter keratoderma (EPPK).

To investigate the relationship between the clinical features and (CAG)n trinucleotide repeats in two pedigrees of Chinese Huntington's disease (HD). Clinical and neuroimaging features, the age of disease onset and pattern of transmission of the patients were studied in the two pedigrees of HD. Genomic DNA of 42 family members was used for amplification of the (CAG)n repeats of IT15 gene by PCR. The numbers of (CAG)n were determined by electrophoresis through a 6% polyacrylamide gel and direct sequence analysis. Results showed that patients in pedigree 1 were absent of the typical triad of HD symptoms or caudate atrophy. A total of 9 (5 patients and 4 asymptomatic) out of 18 family members had 40-50 (CAG)n repeats in the IT15 gene. In pedigree 2, all the patients were characterized by a triad of symptoms, including motor disturbance, cognitive impairment and psychiatric features. Three patients and two asymptomatic relatives had more than 50 (CAG)n repeats in the IT15 gene. In conclusion, the clinical symptoms are partly determined by (CAG)n repeats in the IT15 gene. The age of onset was correlated with (CAG)n repeats over 50, and the phenomenon called "anticipation" was found to have played a role.

Objective: To report a Chinese Charcot-Marie-Tooth disease type 2 (CMT2) family., Methods: All the members in the family were studied clinically,and 6 patients were studied electrophysiologically. Sural nerve biopsy was performed in the proband. PMP22 gene duplications were detected by highly polymorphic short tandem repeat. Point mutation analysis of PMP22, MPZ and NEFL gene was screened by PCR-SSCP combined with DNA direct sequencing. A genome-wide screening was carried out to the family., Result: Except 2 who had weakness and atrophy in both proximal and distal muscles of the lower limbs, all patients presented muscle wasting and a predominating weakness of distal parts of the lower limbs, and mild to moderate sensory impairments. In 6 patients who were subjected to elctrophysiological examinations, median-nerve conduction velocity (NCV) of the median nerve was normal. Electromyograms (EMGs) revealed signs of denervation with large motor unit potentials, fibrillation potentials and positive sharp waves. Sural nerve biopsy of the proband confirmed the presence of axonal neuropathy with an important loss of large myelinating fibers and a large number of clusters with mostly thinly myelinated axons. PMP22, MPZ and NEFL gene mutations were not found. The results of genome-wide screening revealed a linkage of CMT2 to a locus at chromosome 12q24., Conclusion: The results are consistent with the diagnosis of CMT2. This family represents a rare genetic type of CMT2 which can be designated as CMT2L.

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.

Objective: To identify mutations of keratin 9 (KRT9) gene in a big Chinese family with epidermolytic palmoplantar keratoderma(EPPK) combined with knuckle-pad-like lesions and nail lesions., Methods: Genomic DNA from peripheral blood of all available members in this family and 50 unrelated healthy individuals was used for amplification of the whole coding sequence and the intron-exon boundaries of KRT9 gene by PCR; The mutation was detected by direct sequence analysis and identified by restriction endonuclease Dde I., Results: A mutation of AAT>AGT at codon 160 (N160S) was found in all patients but not in unaffected family members and 50 controls., Conclusion: The mutation of AAT>AGT at codon 160 (N160S) is the disease-causing mutation in this Chinese pedigree with EPPK.

To investigate the relationship between X chromosome and obligatory gene of a pedigree with congenital nystagmus,we used the following markers: DXS1214, DXS1068, DXS993, DXS8035, DXS1047, DXS8033, DXS1192 and DXS1232. Genome screening and genotyping were conducted in this pedigree of congenital nystagmus, and linkage analysis by LINKAGE package was used to determine the potential location. The linkage was not found on the Xp (All LOD score <-1) but on Xq (the maximum LOD score=2). The related gene of this pedigree was located on the long arm of X chromosome. We demonstrate that Xq26-Xq28 is a common locus for CMN. It bring us closer to the identification of a gene responsible for X-linked CMN.