Cloning and characterization of a pyridoxine 5'-phosphate oxidase from silkworm, Bombyx mori

A cDNA encoding Pyridoxine 5'-phosphate oxidase (PNPO) from Bombyx mori was cloned and characterized (GenBank accession number: DQ452398). The cDNA encodes a polypeptide of 257 amino acid residues. The recombinant enzyme purified from Escherichia coli exhibited maximal activity at pH 9.0, and the K(m) values for the substrates of pyridoxine 5'-phosphate and pyridoxamine 5'-phosphate were determined as 0.65 and 1.15 micromol/l. It was found that B. mori PNPO shares 51.44% homology with humans, but several function-related, key amino acid residues in B. mori PNPO are different from the human and E. Coli gene. B. mori has a single copy of the PNPO gene, which spans a 3.5 kb region and contains five exons and four introns. B. mori PNPO is a homodimer, with each monomer containing nine antiparallel beta-strands and five alpha-helical segments. The secondary structure was deduced from computational study.

HLA class I allele and haplotype diversity in Ugandans supports the presence of a major east African genetic cluster

The objective of this study was to characterize the class I human leukocyte antigen (HLA) genetic composition of the Ugandan population to better define its relationship with other African groups. Samples from 175 individuals from Kampala (Uganda) were subjected to class I HLA-A, -B, and -C sequence-based typing. The high concordance between the major alleles and haplotypes found in the current and Kenyan populations and interpopulation genetic distance analysis strongly supported the presence of an East African cluster that contained the current Ugandan population along with Kenyan Luo and Nandi populations. The congruence of major alleles in different populations would permit consideration of East Africa as an integrated setting when designing and evaluating much needed malaria, tuberculosis, and AIDS vaccines.

Serum bilirubin levels on ICU admission are associated with ARDS development and mortality in sepsis

BACKGROUND

Hyperbilirubinaemia is a common complication of sepsis. Elevated bilirubin may induce inflammation and apoptosis. It was hypothesised that increased serum bilirubin on Intensive Care Unit (ICU) admission contributes to sepsis-related acute respiratory distress syndrome (ARDS).

METHODS

Serum bilirubin on ICU admission was measured in 1006 patients with sepsis. Serial serum bilirubin was analysed prospectively in patients with sepsis who had ARDS for a period of 28 days. The effects of clinical factors and variants of the UGT1A1 gene on serum bilirubin levels were determined. Outcomes were ARDS risk and mortality.

RESULTS

During 60-day follow-up, 326 patients with sepsis developed ARDS, of whom 144 died from ARDS. The hyperbilirubinaemia (>or=2.0 mg/dl) rate in patients with ARDS (22.4%) was higher than in those without ARDS (14.1%, p = 0.002). For each 1.0 mg/dl increase in admission bilirubin, ARDS risk and 28- and 60-day ARDS mortalities were increased by 7% (OR = 1.07; p = 0.003), 20% (OR = 1.20; p = 0.002) and 18% (OR = 1.18; p = 0.004), respectively. Compared with subjects with bilirubin levels <2.0 mg/dl, patients with hyperbilirubinaemia had higher risks of ARDS (OR = 2.12; p = 0.0007) and 28-day (OR = 2.24; p = 0.020) and 60-day ARDS mortalities (OR = 2.09; p = 0.020). In sepsis-related ARDS, serial bilirubin levels in non-survivors were consistently higher than in survivors (p<0.0001). Clinical variables explained 29.5% of the interindividual variation in bilirubin levels, whereas genetic variants of UGT1A1 contributed 7.5%.

CONCLUSION

In sepsis, a higher serum bilirubin level on ICU admission is associated with subsequent ARDS development and mortality.

The correlation between the expression of ABH and Lewis A histo-blood group antigens and the biological behavior of primary pulmonary adenocarcinoma

e19066

Objective: To investigate the correlation between the expression of ABH and Lewis A histo-blood group antigens and the differentiation, tumorigenesis, progression, metastasis and prognosis of primary pulmonary adenocarcinoma. Methods: The expression of ABH and Lewis A histo-blood group antigens were detected in normal tissue (n=30), primary adenocarcinoma (n=103) and corresponding metastatic lesion (n=41) with immunohistochemistry S-P method. Results: The positive expression of A, B, H antigens was found in normal corresponding pulmonary tissue. While in cancer tissue, such expression was absent. The absence in poorly differentiated tumor was significantly higher than in moderate and highly differentiated cell (P<0.001). And the absent expression was statistically higher in tumor with metastasis than in without metastasis (P=0.036),higher in N2 than in N1 group, higher in secondary tumor in than primary focus(P=0.008).There was significantly statistical difference on the absent expression rates among normal pulmonary tissue, primary tumor and metastatic tumor (P<0.001), and having a tendency of increased absence rate. The expression of Lewis A antigen was markedly higher in pulmonary adenocarcinoma than in normal tissue (P=0.024). Concerning Lewis A expression, the significant difference was found in Stage I,II and III+IV cancers (P=0.001), while the positive expression rate in advanced cancer (StageII+III+IV) was remarkably higher than in early cancer (Stage I) . The 5-year survival of positive expression of ABH antigen was 25%, higher than that in negative expression group (P<0.0001). The 5-year survival in positive expression of Lewis A antigen was 7%, lower than in negative group (P=0.0002). Conclusions: The absence of ABH antigen is closely correlated with tumorigenesis, poor differentiation, and metastasis of primary adenocarcinoma. The detection of ABH, Lewis A antigen may be of vital significance for the prognosis.

No significant financial relationships to disclose.

Epidermal growth factor (EGF) gene polymorphism, gastroesophageal reflux disease (GERD), and esophageal adenocarcinoma (EAC) risk

11029

Background: Single nucleotide polymorphisms (SNPs) of key cancer genes, such as EGF A61G, are associated with an elevated risk of EAC, but the lack of full penetrance indicates that the effects of these SNPs on esophageal carcinogenesis are modified by additional genetic or environmental variables. Since GERD is an established risk factor for EAC, we evaluated whether the association between EGF polymorphism and EAC development is altered by the presence of GERD. Methods: EGF genotyping of DNA samples was performed and GERD history was collected for 309 EAC patients and 275 matched healthy controls. Associations between genotypes and EAC risk were examined with adjusted logistic regression. Genotype-GERD relationships were explored using analyses stratified by GERD history and joint effects models that considered severity and duration of GERD symptoms. Results: Baseline characteristics were comparable between cases and controls except that EGF variants (A/G or G/G) were more common (p=0.02) and GERD was more prevalent (p<0.001) in cases than in controls. When compared to the EGF wild type A/A genotype, the G/G variant was associated with an increased risk of EAC (OR 1.9; 95% CI, 1.2–3.0; p=0.007). Stratified analyses revealed that the G/G variant contributed to a substantial increase in EAC risk among individuals with GERD, but a slight decrease in risk for GERD-free individuals (see table). In the joint effects models, the odds of EAC was also highest for G/G patients who either experienced frequent GERD of more than once per week (OR 21.8; 95% CI, 5.1–94.0; p<0.001) or suffered GERD for longer than 15 years (OR 22.4; 95% CI, 6.5–77.6; p<0.001). There was a highly significant interaction between the G/G genotype and the presence of GERD (p<0.001). Conclusions: EGF A61G polymorphism exerts its effect on EAC susceptibility through an interaction with GERD. Performing EGF genotyping for patients with severe or longstanding GERD can help to identify individuals at the greatest risk of EAC. [Table: see text]

No significant financial relationships to disclose.

Effect of metronomic use of zoledronic acid (ZOL) on antitumor and antiosteoclastic effects in breast cancer patients with bone metastasis

e14603

Background: Zoledronic acid (ZOL) can reduce the risk of skeletal-related events (SREs) and may have direct and indirect antitumor effects, which have been shown in animal models, pilot clinical studies as well as in recent phase III randomized trials. However, the pharmacokinetics of the drug in breast cancer patients remains to be elucidated and optimized. The purpose of this randomized study was to compare the effects of ZOL on osteoclasts and angiogenesis between a weekly low-dose versus a conventional dosage. Methods: Sixty breast cancer patients with bone metastases were recruited in this randomized phase II clinical study. The participants either received ZOL 1mg IV weekly for 4 doses or a single dose of ZOL 4mg IV. No other antitumor treatments were administered. During the first month after initial infusion of ZOL, serial blood samples were collected on day 1, 15 and 29 measuring markers for bone resorption (NTx), angiogenesis (VEGF), and tumor burden (CEA and CA15–3). Results: Compared to a single-dose administration, weekly low dose of ZOL resulted in a greater reduction in serum levels of VEGF and NTx, with a significant trend over time during one month observation. There were no statistically significant differences in circulating levels of CEA and CA15–3 between the two dosing regimens. Patients who received metronomic ZOL had a longer median time to disease progression (TTP) (7.0 months, 95%CI, 6.1–7.9 months) than those who had a single dose of ZOL (2.8 months, 95%CI, 0–5.7 months; p=0.076). Conclusions: The metronomic use of low-dose ZOL 1 mg appeared to be more effective than the conventional regimen in the long-lasting reduction of VEGF and NTx, and in prolonging TTP. This dosing schedule should be further assessed in phase III trials as we demonstrated that ZOL 1mg has greater antitumor properties in our study.

No significant financial relationships to disclose.

Interlaboratory assay reproducibility study for loss of heterozygosity on chromosome 18 (18q LOH) in colon cancer

4052

Background: 18q LOH may be a useful marker in stage II colon carcinoma to assess who needs adjuvant chemotherapy. The objective of this study was to evaluate the intra- and inter-laboratory reproducibility of an assay for 18q LOH that is similar to the integral assay used in E5202, the current Intergroup phase III stage II colon carcinoma clinical trial. Methods: Specimens from 130 stage II/III colon cancer patients were obtained from the Cooperative Human Tissue Network and evaluated at three different laboratories. Samples were divided into subsamples, coded and distributed. Each laboratory used similar equipment in an established PCR protocol with 5 dinucleotide repeats. Starting materials used both histologic sections and extracted DNA samples of tumor and non-neoplastic tissue obtained only by scalpel microdissection. LOH was defined as tumor/normal peak ratio that was >1.35 or <0.67 without microsatellite instability (MSI). Tumors were categorized as either MSI+, LOH + or -, uninformative/monoallelic, or unevaluable (DNA not amplifiable). Standard tests assessed reproducibility of both the numerical ratios and the tumor 18q LOH status. Results: Sample quality issues prevented analysis of 13 tumors (10%). The frequency of 18q LOH was 64%. The probability of agreement on the same tumor evaluated twice was 92% (Cohen's kappa 0.83). Intra-class correlation coefficients for individual markers were consistently over 0.90. Tissue specimens must have high (>85%) tumor cell content for reproducibility. Differences among patients affected reproducibility much more than effects of laboratory and sample type (DNA vs. histologic section). Conclusions: This study validates reproducibility of the 18q LOH assay for both clinical categorization of status and numerical ratios if samples are high quality and appropriate for scalpel microdissection.

[Table: see text]

Prevalence of human respiratory viruses in adults with acute respiratory tract infections in Beijing, 2005-2007

To determine the aetiological role and epidemiological profile of common respiratory viruses in adults with acute respiratory tract infections (ARTIs), a 2-year study was conducted in Beijing, China, from May 2005 to July 2007. Nose and throat swab samples from 5808 ARTI patients were analysed by PCR methods for common respiratory viruses, including influenza viruses (IFVs) A, B, and C, parainfluenza viruses (PIVs) 1-4, enteroviruses (EVs), human rhinoviruses (HRVs), respiratory syncytial virus (RSV), human metapneumovirus (HMPV), human coronaviruses (HCoVs) OC43, 229E, NL63, and HKU1, and adenoviruses (ADVs). Viral pathogens were detected in 34.6% of patient samples, and 1.6% of the patients tested positive for more than one virus. IFVs (19.3%) were the dominant agents detected, followed by HRVs (6.5%), PIVs (4.3%), EVs (3.2%), and HCoVs (1.1%). ADVs, RSV and HMPV were also detected (<1%). The viral detection rates differed significantly between infections of the lower and upper respiratory tracts in the sample population: PIVs, the second most commonly detected viral agents in lower acute respiratory tract infections (LRTIs), were more prevalent than in upper acute respiratory tract infections, indicating that the pathogenic role of PIVs in LRTIs should be investigated. Currently, this study is the largest-scale investigation of respiratory virus infections in China with multiple agent detection, providing baseline data for further studies of respiratory virus infections in adults with ARTIs.

Learning brain connectivity with the false-discovery-rate-controlled PC-algorithm

Discovering the connectivity networks in the brain, i.e. the neural influence that brain regions exert over one another, has attracted increasing research attention in studies on brain functions. An important error rate criterion on the discovered network is the false discovery rate (FDR), that is the expected ratio of the falsely 'discovered' connections to all those 'discovered'. Very recently, we have developed an algorithm that is able to control the FDR under a given level q at the limit of large sample size, and its modification that controlled the FDR accurately in simulations with moderate sample sizes [1]. However, the algorithms do not consider prior knowledge on the network structure, and can not be applied to models such as dynamic Bayesian networks. In this paper, we extend the algorithms to incorporate prior knowledge, and demonstrate how to apply the extended algorithm to learning the structure of dynamic Bayesian networks from continuous data. Its application to a real functional-Magnetic-Resonance-Imaging (fMRI) data set revealed that Parkinson's disease patients' brain connectivities are normalized by L-dopa medication. This result is consistent with the fact that L-dopa has dramatic effects against bradykinesia and rigidity.

Clinicopathological characteristics of familial SLE patients with lupus nephritis

This study aimed to analyze the clinicopathological characteristics of familial SLE patients with lupus nephritis (LN). A total of 136 Chinese patients with lupus nephritis diagnosed by renal biopsy, including 34 familial patients and 102 sporadic cases, were recruited. Their demographic information, age of onset, disease duration, clinical features, laboratory data and histological manifestations were compared. The first-degree relatives (17 sibling cases and eight parent-offspring cases) of familial SLE patients were primarily affected. The prevalence of fever, rash and arthritis in familial subjects was higher than that in sporadic subjects. Familial patients had lower platelet counts and higher low-density lipoprotein. In familial patients, class V lupus nephritis was less common. After adjusted with the Benjamini and Hochberg procedure, however, fever was the only feature occurring significantly and more frequently in familial patients (58.8% vs 26.5%, P = 0.001). Moreover, SLEDAI and other clinicopathological features did not differ significantly between the two groups. Multivariate analysis showed that a higher prevalence of fever was an independent predictor of familial SLE. Most clinicopathological features in familial SLE patients were not significantly different from those in sporadic patients; the severity of LN in familial SLE patients was similar to that of sporadic cases. Thus, familial SLE may not be a different clinical entity.

A simple and evolutional approach proven to recanalise the nasolacrimal duct obstruction

Aim:

To evaluate a new approach of recanalisation of nasolacrimal duct obstruction (RC-NLDO) in the treatment of the nasolacrimal duct obstruction (NLDO) and chronic dacryocystitis.

Methods:

583 patients with 641 eyes suffering from NLDO and chronic dacryocystitis were enrolled in this study. The RC-NLDO was performed in 506 eyes, with 135 eyes undergoing external dacryocystorhinostomy (EX-DCR) as controls. Patient follow-up for 54 months was evaluated by symptoms, dye disappearance test, lacrimal irrigation and digital subtraction dacryocystogram. The RC-NLDO was also performed in 12 rhesus monkeys for histopathological examination.

Results:

The clinical success rates were 93.1% in 506 cases of RC-NLDO and 91.11% in 135 cases of EX-DCR. The success rates for second surgery were achieved in 85.19% on RC-NLDO and 40.0% on EX-DCR. No major intra- or postoperative complications were observed in the RC-NLDO group. The mean operative duration was 12.5 min for RC-NLDO and 40.3 min for EX-DCR (p<0.001). A pathological study in rhesus monkeys demonstrated that the RC-NLDO wounded epithelium in nasolacrimal duct healed completely within 1 month without granulation tissue formation.

Conclusion:

The findings demonstrate that the RC-NLDO is a simple and effective approach proven to recanalise the obstructed nasolacrimal duct with a comparable success rate to EX-DCR.

A dendritic cell-based tumour vaccine for lung cancer: full-length XAGE-1b protein-pulsed dendritic cells induce specific cytotoxic T lymphocytes in vitro

XAGE-1b is regarded as one of the most immunogenic antigens and the most promising targets for lung adenocarcinoma immunotherapy. In this study, we sought to determine whether monocyte-derived dendritic cells (DCs) pulsed with purified full-length XAGE-1b could induce specific cytotoxic T lymphocytes (CTLs) against tumour cells from patients with non-small cell lung cancer (NSCLC) in vitro. XAGE-1b mRNA expression was examined in primary cultures of lung cancer cells and normal lung epithelial cells established from fresh tissues surgically resected from 30 patients with NSCLC using reverse transcription-polymerase chain reaction (RT-PCR). XAGE-1b mRNA expression was observed in 11 of 18 (61.1%) adenocarcinomas and one of 12 (8.3%) lung cancers of other histological types (P = 0.015). The 246-base pairs XAGE-1b gene was inserted into a recombinant expression vector. Full-length XAGE-1b was then expressed in BL21 (DE3) Escherichia coli and purified by AKTA-fast performance liquid chromatography (FPLC). DCs generated from peripheral blood mononuclear cells were pulsed with XAGE-1b by incubation with the protein at an immature stage. The XAGE-1b-pulsed DCs induced CTLs following 14 days of co-culture. Finally, an adherent target detachment (ATD) assay was performed to test the cytotoxicity of the XAGE-1b-specific CTLs against cancer cells and normal lung epithelial cells. The XAGE-1b-specific CTLs had a stronger lytic effect on autologous XAGE-1b mRNA-positive cancer cells than on autologous XAGE-1b mRNA-negative cancer cells or allogenous XAGE-1b mRNA-positive cancer cells. The CTLs had no lytic activity against normal lung epithelial cells. These results can be used to develop simple and effective cancer/testis antigen-based immunotherapies for NSCLC.