Genetic analysis of mucopolysaccharidosis type VI in Taiwanese patients

BACKGROUND: Glutathione peroxidase 1 (GPX1), the key antioxidant enzyme in vascular endothelial cells, has been shown to exert a protective effect against the presence of coronary artery disease (CAD). The 198Pro/leu variant, located at codon 198 of GPX1 gene, has recently been linked to cardiovascular disease, but data were inconsistent. We investigated the association between the occurrence of CAD and the 198Pro/leu variant in a Chinese population. METHODS: A total of 265 unrelated CAD patients and 265 age- and sex-matched control subjects were recruited in this study. The GPX1 198Pro/leu genotype was determined using polymerase chain reaction-restriction fragment length polymorphism. RESULTS: Compared to the 198Pro/Pro carriers, subjects with the variant genotypes (198Pro/leu and 198Leu/leu) had a significantly higher risk of CAD (adjusted OR=2.02, 95%CI=1.27-3.22). In stratified analyses, the variant genotypes were significantly associated with increased CAD risk in subjects <64 y (adjusted OR=2.41, 95%CI=1.16-4.98), males (adjusted OR=1.86, 95%CI=1.09-3.18) and non-smokers (adjusted OR=2.40, 95%CI=1.15-5.01). However, no significant association was observed between this variant and the severity of CAD. CONCLUSION: These data provide evidence that GPX1 198Pro/leu variant genotypes are significantly associated with CAD risk in this Chinese population.     

Plasmacytoid dendritic cells induce NK cell-dependent, tumor antigen-specific T cell cross-priming and tumor regression in mice

A prerequisite for strong adaptive antiviral immunity is the robust initial activation of the innate immune system, which is frequently mediated by TLR-activated plasmacytoid DCs (pDCs). Natural antitumor immunity is often comparatively weak, potentially due to the lack of TLR-mediated activation signals within the tumor microenvironment. To assess whether pDCs are capable of directly facilitating effective antitumor immune responses, mice bearing established subcutaneous B16 melanoma tumors were administered TLR9-activated pDCs directly into the tumor. We found that TLR9-activated pDCs induced robust, spontaneous CTL cross-priming against multiple B16 tumor antigens, leading to the regression of both treated tumors and untreated tumors at distant contralateral sites. This T cell cross-priming was mediated by conventional DCs (cDCs) and was completely dependent upon the early recruitment and activation of NK cells at the tumor site. NK cell recruitment was mediated by CCR5 via chemokines secreted by pDCs, and optimal IFN-gamma production by NK cells was mediated by OX40L expressed by pDCs. Our data thus demonstrated that activated pDCs are capable of initiating effective and systemic antitumor immunity through the orchestration of an immune cascade involving the sequential activation of NK cells, cDCs, and CD8(+) T cells.     

Identification of eight novel mutations of the acid α-glucosidase gene causing the infantile or juvenile form of glycogen storage disease type II

Glycogen-storage disease type II (GSDII; OMIM #232300), an autosomal recessive disorder caused by a deficiency of the glycogen hydrolysis enzyme acid alpha-glucosidase (acid GAA; acid maltase, EC. 3.2.10.20), results in the accumulation of glycogen in the lysosome. We performed a molecular genetic study on 29 patients with infantile-onset glycogen-storage disease type II (GSDII), 6 with juvenile-onset GSDII and one carrier for GSDII. Seventeen different mutations were identified among them; 8 were novel mutations: c.421C > A (p.L141M), c.872T > C (p.L291P), c.893A > C (p.Y298S), c.1375G > A (p.D459N), c.1437G > C (p.K479N), c.1509_1511del (p.A504del), c.1960T > C (p.S654P), and c.2174G > C (p.R725P). One of the mutations identified, c.2238G > C (p.W746C), which was a sequence change of unknown pathogenic significance causing diminished enzyme activity,was found homozygously in a juvenile-onset patient. We also found a juvenile-onset patient with homozygote c.1935C > A mutation which was frequently found in infantile-onset patients. In addition to mutations, we also identified 14 new polymorphisms in the acid alpha-glucosidase gene. The genotype/phenotype correlations indicated that c.2238G > C (p.W746C) is correlated with juvenile- onset GSDII and that c.872T > C (p.L291P) and c.1411_1414del (p.E471fsX5) are correlated with infantile-onset GSDII. Mutational analysis of GAA is useful in genetic counseling and prenatal diagnosis of the disease.     

Case of vemurafenib‐induced Sweet's syndrome

Vemurafenib is a targeted therapy that has become standard treatment for patients with advanced melanoma with a V600E BRAF mutation. It has been associated with frequent skin toxicity, including photosensitivity, rash and squamous cell carcinomas. We present an 83‐year‐old woman with an advanced V600E BRAF‐mutant melanoma who developed a severe skin rash and fatigue after taking vemurafenib. The dose was reduced from 960 to 720 to 480 mg twice a day; however, she was subsequently admitted to the hospital with fever, chills, fatigue, confusion and a diffuse skin eruption. She then developed hypoxia and acute renal failure that required hemodialysis. A biopsy of her skin lesions revealed a neutrophilic dermatitis with papillary dermal edema, consistent with Sweet's syndrome. Her symptoms resolved upon discontinuation of vemurafenib and treatment with prednisone. This constellation of symptoms and clinical course are consistent with drug‐induced Sweet's syndrome caused by vemurafenib.     

Brief alcoholism screening questionnaire: establishment and validity in Taiwanese.

BACKGROUND AND PURPOSE: There has been a marked increase in the prevalence of alcoholism in the Taiwanese population over the past 6 decades. This study was designed to establish a Taiwanese Brief Alcoholism Screening Questionnaire (BASQ) for use in early detection in medical and public health settings. METHODS: Interview data were collected from the database of the Taiwan Psychiatric Epidemiological Project (TPEP). The TPEP interviews had been conducted using the Chinese-modified version of the Diagnostic Interview Schedule (DIS-CM) that included a section on alcoholism diagnosis. Data collected from a community sample of 13,373 subjects was used in this study. Twenty nine DIS-CM items for alcoholism diagnosis were entered into an analytic model with 7 statistical filters to identify cross-cultural items. A brief alcoholism screening questionnaire was constructed using these selected items. The validity of the questionnaire was tested in subjects (n = 457) recruited from a local medical center, a hospital clinic, and an alcoholism clinic of a psychiatric center. RESULTS: Four cross-cultural items were identified and the BASQ was constructed. This BASQ had a best cut-off point of 3 with adequate sensitivity (0.86 to 0.88), specificity (0.88 to 0.89), and positive prediction rate (0.90 to 0.91). It detected a varying prevalence of alcoholism (10.1 to 90.3%) in diverse clinical settings. CONCLUSIONS: A 4-item BASQ was established with adequate validity for clinical and public health application in the early detection of alcoholism in Taiwanese subjects.     

IL-21 synergizes with IL-7 to augment expansion and anti-tumor function of cytotoxic T cells

IL-21, a recently identified member of the common gamma-chain (gammac) receptor cytokine family, has been shown to be an important regulator of both innate and adaptive immune responses. In this study, we investigated whether IL-21 could synergize with another gammac cytokine, IL-7, to induce enhanced proliferation and effector function of tumor antigen-specific CD8(+) T cells. Our results showed that IL-21 could significantly augment the IL-7-induced expansion of cytotoxic T cells, possibly by preventing the cytokine-induced down-regulation of the IL-7Ralpha (CD127) on antigen-stimulated T cells. IL-21 also greatly enhanced the production of T(h)1 and inflammatory cytokines by activated T cells, including IFN-gamma, IL-2, tumor necrosis factor-alpha, granulocyte macrophage colony-stimulating factor, IL-1beta and IL-6. Finally, the addition of IL-21 to IL-7-cultured CTLs resulted in a considerably higher level of cytolytic activity, as measured by specific killing of tumor cells or antigen-pulsed target cells. These results suggest that IL-21 may play a cooperative role with IL-7 in modulating primary CD8(+) T-cell responses and may have important implications for immunotherapy of cancer.     

HTF9C gene of 22q11.21 region associates with schizophrenia having deficit-sustained attention

OBJECTIVE: A region at chromosome 22q11.21 has been reported to potentially harbor a candidate gene for schizophrenia, ZDHHC8 (zinc finger, DHHC domain containing 8; also annotated as KIAA1292) in a number of studies. This finding has been replicated in Han Chinese, but not in other ethnicity-specific studies. For further support from within the Han Chinese ethnic group, we selected two single nucleotide polymorphisms (SNP) located at the distal 5'-end (rs1633445; intron 10 of HpaII tiny fragments locus 9C, HTF9C) and the intron 4 (rs175174) of ZDHHC8 gene to test if these were associated with schizophrenia in a study sample of Taiwan. METHODS: A total of 218 schizophrenia families with at least two affected siblings participated in this study. These two SNPs were genotyped using matrix-assisted laser desorption/localization ionization time of flight (MALDI-TOF) mass spectrometry. RESULTS: Significant associations with schizophrenia were not shown from these two SNPs. After stratifying schizophrenia according to the deficit and the nondeficit of sustained attention assessed by the Continuous Performance Test, the rs1633445 showed significant association with schizophrenia in the presence of a deficit in sustained attention (P<0.04). CONCLUSION: SNP rs1633445 of the HTF9C gene may be associated with a deficit in sustained attention within schizophrenia, in a Taiwanese cohort. The deficit of sustained attention may be an endophenotype of schizophrenia, and warrants further study.     

Survivin DNA vaccine generated specific antitumor effects in pancreatic carcinoma and lymphoma mouse models

We investigated the antitumor effect of survivin DNA vaccine in murine pancreatic and lymphoma models, and if xenogenic survivin can generate stronger immune response. We found that mice vaccinated with either human or mouse survivin DNA have significantly slower tumor growth and longer survival than those vaccinated with vector DNA. There was no significant difference between groups that received human and mouse survivin DNA. Lymphocyte infiltration was greater in tumors of mice immunized with survivin DNA than in tumors of control mice. We conclude that survivin DNA vaccine generated specific antitumor effects with increased lymphocyte infiltration at the tumor sites.     

Management of Leigh syndrome: Current status and new insights

Leigh syndrome (LS) is an inherited mitochondrial encephalopathy associated with gene mutations of oxidative phosphorylation pathway that result in early disability and death in affected young children. Currently, LS is incurable and unresponsive to many treatments, although some case reports indicate that supplements can improve the condition. Many novel therapies are being continuously tested in pre‐clinical studies. In this review, we summarize the genetic basis of LS, current treatment, pre‐clinical studies in animal models and the management of other mitochondrial diseases. Future therapeutical strategies and challenges are also discussed.