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This present study deals with synthesis, characterization and antibacterial activity of cross-linked chitosan-glutaraldehyde. Results from this study indicated that cross-linked chitosan-glutaraldehyde markedly inhibited the growth of antibiotic-resistant Burkholderia cepacia complex regardless of bacterial species and incubation time while bacterial growth was unaffected by solid chitosan. Furthermore, high temperature treated cross-linked chitosan-glutaraldehyde showed strong antibacterial activity against the selected strain 0901 although the inhibitory effects varied with different temperatures. In addition, physical-chemical and structural characterization revealed that the cross-linking of chitosan with glutaraldehyde resulted in a rougher surface morphology, a characteristic Fourier transform infrared (FTIR) band at 1559 cm-1, a specific X-ray diffraction peak centered at 2? = 15°, a lower contents of carbon, hydrogen and nitrogen, and a higher stability of glucose units compared to chitosan based on scanning electron microscopic observation, FTIR spectra, X-ray diffraction pattern, as well as elemental and thermo gravimetric analysis. Overall, this study indicated that cross-linked chitosan-glutaraldehyde is promising to be developed as a new antibacterial drug. [ABSTRACT FROM AUTHOR]

Peroxisomes are cellular organelles present ubiquitously in eukaryotic cells and are involved in β-oxidation, glyoxylate cycle and a variety of biochemical metabolisms. Recently peroxisomes have been demonstrated to play vital roles in the host infection processes by plant fungal pathogens. The biogenesis of peroxisomes requires a category of proteins named peroxins, which are encoded by the PEX genes. So far, more than 10 PEX genes were isolated in phytopathogenic fungi, and significant research efforts are focused on the mechanism of peroxisome formation and the roles of peroxisome in the development and pathogenicity of fungal pathogens. In this review, we summarize the latest advances in peroxisome biogenesis and functions in pathogenic fungi, including the roles of PEXs in life cycle of peroxisome, peroxisome related metabolisms, and fungal development, infection and pathogenicity, in order to provide references for future studies in plant pathogenic fungi and the control of disease.

The family members of PEX11 are key factors involved in regulation of peroxisome proliferation. Sixty-six PEX11p candidates of PEX11 gene family from 26 representative fungal species were obtained and analyzed by bioinformatic strategies. In most filamentous fungi, 2 or 3 potential PEX11ps were found, in contrast with 1 or 2 in yeast species. Compared with other fungal species, the Ascomycetes tend to have more PEX11ps, and even 5 in several individuals. The data of phylogenetic analysis and protein structure indicated that all of the PEX11ps were divided into 3 groups: I, II, and III. The members of group I and group III existed in most species, while those in group II were found only in Pezizomycotina. By MEME analysis, 5-6 conserved motifs were found in each PEX11ps. Among them,motif 8 in C-terminal had the most conservation, indicating that this motif probably plays a key role in maintaining the proper function of PEX11p.

Rice blast, caused by the fungal pathogen Magnaporthe grisea, is one of the most devastating diseases of rice. The specific interaction between rice and M. grisea is an important model system for studying the host-pathogen interaction mechanisms. In this article, we summarized recent research progresses on avirulence genes, which are the most important effectors in M. grisea with the focus on chromosome mapping, cloning method, functional analysis, and evolution study of avirulence genes, and the possible hotspot of the research on avirulence genes in the future was also been discussed. This knowledge may shed a light on the molecular mechanism underlying avirulence genes function and the possible interaction relationship between the host and the pathogen.

Targeted gene replacement (TGR) is an important technique for gene function analysis. With the development of genome sequencing and transformation, TGR has been applied widely to filamentous fungi, and many new systems and approaches have been established. In this paper, strategies involved in TGR in filamentous fungi were reviewed, including transformation systems, targeting vector construction, mutant selection and so on. Compared with TGR, RNAi and other techniques of gene function analysis were introduced and reviewed as well.

Objective: To assess the association of haplotype of HLA-DRB1 and HLA-DQA1 alleles with outcomes of hepatitis B virus infection in Han population of north China., Methods: Two hundred and seven chronic hepatitis B (HB) patients, two hundred and twelve chronic asymptomatic hepatitis B virus (HBV) carriers (HBV carrier) and one hundred and forty-eight self-limited HBV infection were investigated for HLA-DRB1 and HLA-DQA1 alleles by sequence specific-polymerase chain reaction (PCR-SSP)., Results: The frequency of DRB1*04-DQA1*0301 haplotype was 10.03% in self-limited HBV infection subjects, significantly higher than that in chronic HB patients (3.66%) (P=0.0005)ûthe frequency of DRB1*15/*16-DQA1*0102 haplotype was 6.80% in self-limited HBV infection subjects, significantly higher than 1.94% in chronic HB patients (P=0.0012) and 1.65% in asymptomatic HBV carriers (P=0.0004)ûwhile the frequency of DRB1*04-DQA1*0302 haplotype was 3.10% in chronic HB patients, higher than that in self-limited HBV infection subjects (0.39%) (P=0.0077)., Conclusion: Individuals with different haplotypes composed of HLA-DRB1 and HLA-DQA1 might have different outcomes of HBV infection.

Objective: To assess the association of polymorphisms of human leucocyte antigen (HLA) -DRB1 and -DQA1 region allele with outcomes of hepatitis B virus (HBV) infection in Han population of north China., Methods: A total of 207 chronic hepatitis B (HB) patients, 212 chronic asymptomatic HBV carriers (HBV carrier), and 148 self-limited HBV infection were recruited to examine the association between gene polymorphisms and outcomes of HBV infection. Polymerase chain reaction-sequence specific primers (PCR-SSP) technique was used to genotype HLA-DRB1 and HLA-DQA1 loci., Results: The frequency of HLA-DQA1 * 0301 in chronic HB patients (14.81%) was significantly lower than those in HBV carriers (25.24%) and self-limited HBV infection subjects (25.00%) (Pc = 0.002; Pc = 0.007). The frequency of HLA-DQA1 * 0102 in self-limited HBV infection subjects (8.78%) was significantly higher than those in chronic HB patients (2.18%) and HBV carriers (1.89%) (Pc = 0.000; P = 0.000). In addition, the frequency of HLA-DQA1 * 0302 in self-limited HBV infection subjects (4.05%) was significantly lower than that in chronic HB patients (11.41%) (Pc = 0.005). HLA-DQA1 * 0302 was demonstrated to be risk factors of chronic HBV (OR = 3.913, P = 0.0006), while HLA-DQA1* 0102 and HLA-DQA1 * 0301 to be protective factors against chronic HBV (OR = 0.200, P = 0.0004; OR = 0.258, P = 0.0000) after age, sex, smoking and drinking were adjusted by logistic regression analysis. There were positive interactions between drinking and HLA-DQA1 * 0102 [interaction index (II) = 1.49] or HLA-DQA1 * 0302 (II = 12.12). There were negative interactions between drinking and HLA-DQA1 * 0301 (II = 0.78), Conclusions: The subjects with HLA-DQA1 * 0302 allele have an increased risk to chronic HB infection compared with other subjects without this allele, while HLA-DQA1 * 0301 and HLA-DQA1 * 0102 are associated with HBV clearness. Gene-environment interaction can affect the outcomes of HBV infection.

Aim: To clarify whether -238G/A polymorphism of tumor necrosis factor-alpha (TNF-alpha) gene promoter region was associated with outcomes of hepatitis B virus (HBV) infection in Han population of northern China, and to analyze the gene-environment interaction between -238G/A polymorphism and cigarette smoking or alcohol consumption., Methods: A case-control study was conducted to analyze the association of TNF-alpha gene promoter polymorphism with HBV infection outcomes. A total of 207 patients with chronic hepatitis B (HB) and 148 cases of self-limited HBV infection from Ditan Hospital and Shunyi District Hospital in Beijing, respectively were recruited. History of smoking and alcohol drinking was inquired by a questionnaire. The -238G/A polymorphism of TNF-alpha gene promoter was genotyped by polymerase chain reaction-restricted fragment length polymorphism (PCR-RFLP)., Results: The frequencies of GG and GA genotypes were 98.07% and 1.93% in chronic HB patients and 93.24% and 6.76% in self-limited HBV infection individuals, respectively (chi(2)=5.30, P=0.02). The frequency of G allele was significantly higher in patients with chronic HB that in individuals with self-limited HBV infection (99.03% vs 96.62%, chi(2)=5.20, P=0.02). Only modestly increased risk of onset of chronic HB was found in smokers (OR=1.40, 95% CI: 0.87-2.28, P=0.14) and drinkers (OR=1.26, 95%CI: 0.78-2.05, P=0.32). There was a positive interaction between genotype GG and cigarette smoking with an interaction index (II) of 2.95, or alcohol consumption with an II of 1.64., Conclusion: The -238G/A polymorphism of TNF-alpha gene promoter region is independently associated with different outcomes of HBV infection.