Unexpected assembly machinery for 4(3H)-quinazolinone scaffold synthesis.

4(3H)-quinazolinone is the core scaffold in more than 200 natural alkaloids and numerous drugs. Many chemosynthetic methodologies have been developed to generate it; however, investigation of its native enzymatic formation mechanism in fungi has been largely limited to fumiquinazolines, where the two nitrogen atoms come from anthranilate (N-1) and the α-NH2 of amino acids (N-3). Here, via biochemical investigation of the chrysogine pathway, unexpected assembly machinery for 4(3H)-quinazolinone is unveiled, which involves a fungal two-module nonribosomal peptide synthase ftChyA with an unusual terminal condensation domain catalysing tripeptide formation; reveals that N-3 originates from the inorganic ammonium ions or the amide of L-Gln; demonstrates an unusual α-ketoglutarate-dependent dioxygenase ftChyM catalysis of the C-N bond oxidative cleavage of a tripeptide to form a dipeptide. Our study uncovers a unique release and tailoring mechanism for nonribosomal peptides and an alternative route for the synthesis of 4(3H)-quinazolinone scaffolds.

Prenatal diagnosis of harlequin ichthyosis by ultrasonography: a case report.

Autosomal recessive congenital ichthyosis is a genetically and phenotypically heterogeneous group of skin disorders, including harlequin ichthyosis (HI), lamellar ichthyosis, and bullous congenital ichthyosiform erythroderma. HI is the most phenotypically severe autosomal recessive congenital ichthyosis associated with the mutation of the adenosine triphosphate-binding cassette subfamily A member 12 (ABCA12) gene. The clinical manifestations include generalized hyperkeratotic plaques and deep fissures, ectropion, eclabium, and contractures. However, the severe HI may easily be misdiagnosed as epidermolysis bullosa or syndromic ichthyosis. Meanwhile, no consensus exists about the best used in clinical trials or clinical practice when more elaborate scoring systems have been proposed to evaluate skin xerosis, palmoplantar keratoderma, and disease extension an accurate prenatal diagnosis is necessary. Until the ABCA12 gene was identified as the pathogenic gene, prenatal diagnosis of HI had been performed by the invasive techniques of fetal skin biopsy. Now, advances in ultrasound technology and fetal DNA-based analysis have replaced it. The mortality rate is markedly high and prompt; prenatal diagnosis of neonate HI is critical for appropriate perinatal and postnatal management. It is also essential to prepare parents for future pregnancies and reduce the family's physical and mental distress and financial burden. This report presents a rare case of harlequin ichthyosis diagnosed by the ultrasound and discusses the significance of prenatal ultrasound diagnosis and molecular diagnosis in the prenatal diagnosis of HI.

Psychometric Properties of the Chinese Version of the M.D. Anderson Dysphagia Inventory for Head and Neck Cancer Patients.

BACKGROUND: Dysphagia is a common side effect of anticancer treatments in patients with head and neck cancer (HNC) and can worsen patients' quality of life. A well-established measure is essential to evaluate dysphagia in HNC patients. OBJECTIVES: The aim of this study is to determine the psychometric properties of the Chinese version of the M.D. Anderson Dysphagia Inventory (MDADI-C) for HNC patients. METHODS: A total of 220 subjects were included in the study. Reliability was examined by internal consistency (Cronbach's α) and test-retest reliability (intraclass correlation coefficient). Validity was evaluated with Spearman correlations (r). RESULTS: The Cronbach's α and intraclass correlation coefficient of the MDADI-C were .923 and 0.942, respectively. The criterion validity of the MDADI-C was 0.777. The Spearman correlation coefficients of the MDADI-C with the European Organization for Research Into the Treatment of Cancer Quality of Life Questionnaire for Head and Neck Cancer (r = -0.851), Hospital Anxiety and Depression Scale (r = -0.424), radiotherapy dose (r = -0.553), and treatment regimens (r = -0.407) demonstrated good construct validity (all P < .01). CONCLUSIONS: The MDADI-C demonstrated good psychometric properties and would be a valuable tool for clinicians to screen dysphagia rapidly and evaluate its impact on the quality of life of HNC patients. IMPLICATIONS FOR PRACTICE: The MDADI-C could be used to document and monitor the dysphagia level of HNC patients for clinicians, nurses, and researchers. This validated questionnaire will help nurses and doctors to improve dysphagia management in HNC patients and will allow researchers to compare the study results across different countries.

[Investigation of different pregnant results of pregnant women infected with toxoplasma gondii in Nanjing region].

OBJECTIVE: To explore the influence of Toxoplasma gondii infection on pregnant results during different pregnancies of women. METHODS: The antibodies of IgG and IgM against Toxoplasma gondii in peripheral blood were detected by ELISA in 6 849 pregnant women and the antibody of IgM against Toxoplasma gondii in cord blood was also detected in 1 032 newborns in Nanjing City. The general status of these women was investigated with questionnaire, and the outcome of pregnancies of the women was followed up. RESULTS: A total of 6 849 pregnant women were screened, 438 persons were found with antibodies against Toxoplasma gondii, and the positive rate was 6.4%. Among them, 87 women were IgM positive accounting for 19.9%, and 351 IgG positive accounting for 80.1%. Totally 1 032 newborns were screened and they were divided into a normal group and a deformed group according to their health. Among them, the IgM positive rates were 0.6% in the normal group and 28.13% in the deformed group respectively, and there was a statistically significant deference between 2 groups (P < 0.01). The exposure to animals and bad eating habits were the main risk factors for Toxoplasma gondii infection. CONCLUSIONS: Toxoplasma infection can lead to different pregnancy outcomes in pregnant women. The detection of IgM antibody against Toxoplasma gondii may contribute to screening deformed newborns.

[Blockage of allergic rhinitis in mice with recombinant protein of cytotoxic T lymphocyte associated antigen-4 extracellular domain].

OBJECTIVE: To explore a new immunotherapy against allergic rhinitis. METHODS: The recombinant protein of CTLA4 extracellular domain was obtained through construction of CTLA4-yeast expression system. The allergic rhinitis in mice was induced by sensitizing and challenging with ovalbumin (OVA). The allergic rhinitis related symptoms and the morphological changes in nasal mucosa were compared between the allergic rhinitis group and the CTLA4 extracellular domain group treated with CTLA4 extracellular domain before each challenge by ways of intraperitoneal injection. RESULTS: CTLA4 extracellular domain with a molecular weight of 28 000, which was confirmed by Western blot, could be generated through CTLA4-yeast expression system. The purified CTLA4 extracellular domain could inhibit T cells proliferation in mixed lymphocyte reaction with a inhibitory rate of 95.4%. The mice in allergic rhinitis group appeared typical allergic rhinitis symptoms after OVA challenge, such as rhinorrhea and sneeze. Meanwhile the nasal pathological studies showed edema and congestion in mucosa tissue and local influx of inflammatory cells. Whereas in CTLA4 extracellular domain group, the nasal symptoms were rarely observed, and the pathological change in nasal mucosa was significantly abated. CONCLUSIONS: The protein of CTLA4 extracellular domain could prevent the allergic rhinitis in mice. The underlying mechanism of which might be the inhibition of the T cell activation.

[Experimental study on the antibacterial effects of zirconium phosphate gauze loaded with silver on the common bacteria on rat burn wound].

OBJECTIVE: To investigate the antibacterial effects of zirconium phosphate gauze loaded with silver on rat burn wounds seeded with commonly seen bacteria. METHODS: Wistar rats were employed in the study and were scalded and infected. The minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) of zirconium phosphate loaded with silver were determined by double dilution in tubes. The effect on wound healing and the subeschar bacterial count of the rat burn wounds were observed after the wounds had been covered by gauze loaded with zirconium phosphate and silver, and also with the gauze which has been rinsed for 20 times. RESULTS: The MIC of silver loaded zirconium phosphate on Staphylococcus aureus, Pseudomonas aeruginosa and E. coli were 8, 8 and 16 mg/L, respectively, while the MBC were 16, 8 and 32 mg/L, respectively. The subeschar bacterial count in the burn wounds with the gauze with silver loaded zirconium phosphate was ten times lower than that in those which were treated with gauze with SD-Ag and 100 times lower than that with ordinary gauze. But there was no difference in the bacterial count between the wounds which were treated with fresh gauze with silver loaded zirconium phosphate and that with the gauze which has been rinsed for 20 times (P > 0.05). Furthermore, wound healing seemed to be better with the gauze with silver loaded zirconium phosphate when compared with those by the other two kinds of gauze. CONCLUSION: The silver loaded zirconium phosphate was found to be bacteriocidal against bacteria commonly seen in the burn wounds.

[The influence of the application of cytotoxic lymphocyte antigen 4-Ig adenovirus on the burn wounds with alloskin grafting on the murine immune function].

OBJECTIVE: To investigate the influence of local application of cytotoxic lymphocyte antigen 4-Ig (CTLA4-Ig) adenovirus on the burn wound with alloskin grafting upon the murine immune function. METHODS: Sixty BALB/c mice were randomly divided into A (operation control), B (CTLA4-Ig transfection) and C (normal control) groups, with 20 mice in each group. Skin wounds (full-thickness loss) sized 1.5 cm x 1.5 cm were created on the backs of mice in A and B groups. Then the skin grafts of the same size obtained from C57BL mice were grafted into the skin wounds. 0.1 g of cross-linking polyacrylic resin (carbomer cream) without adenovirus was daubed onto the wounds in A group, and the same amount of carbomer cream with adenovirus in titers of 5 x 10(9)/L was daubed onto the wounds in B group, while no treatment was given in C group. 1 ml of 10% SRBC (sheep red blood cell) was injected intraperitoneally to all the mice of the three groups on the 1st post injury day (PID). Splenocytes from BALB/c, C57BL and Kunming mice were harvested for mixed lymphocyte culture on 7, 14, 21 and 28 PIDs. Agglutination assay was used in the same time to detect the SRBC antibody titers. RESULTS: The reaction of murine splenocytes in B group to the donor (C57BL) splenocytes was suppressed in a specific way (P < 0.05) within 14 PIDs. There was no difference in the titers of anti-SRBC antibody among the 3 groups (P > 0.05). CONCLUSION: Local application of CTLA4-Ig recombinant adenovirus exhibited no influence on the murine humoral immunity, but might induce systemic and specific T cell tolerance in immunity system.

[An experimental study on the role of indirect antigen presentation pathway on the immunogenetic of epidermal cells].

OBJECTIVE: To explore the role of indirect antigen presentation pathway on the immunogenecity of epidermal cells. METHODS: Human epidermal cells (HEC), allogeneic human peripheral blood lymphocytes (PBL) and mononuclear cells (PBM, including monocytes) were isolated and cultured in vitro. HECs were transfected by human-originated CTLA4Ig-adenovirus vector. The CTLA4Ig expression was observed. Allogeneic PBLs or PBMs were added to the transfected and non-transfected HECs with simple cultured PBLs and PBMs as the control. The proliferation of PBL and PBM was determined by (3)H-TdR incooperation. RESULTS: HECs could be successfully transfected by CTLA4Ig-adenovirus vector and expressed corresponding proteins. The non-transfected HECs could stimulate slight proliferation of allogeneic PBLs (P < 0.05) and stimulate remarkable proliferation of PBMs (including monocytes) (P < 0.05). The proliferation reaction of PBLs and PBMs decreased significantly (P < 0.05) after being stimulated by HEC which was modulated by CTLA4Ig genes. CONCLUSION: Indirect antigen presentation pathway might play important roles in the HEC immunogenicity which could be evidently inhibited by CTLA4Ig.