[Quality control of perioperative management after radical surgery for locally advanced gastric cancer]

Gastric cancer is a common malignant tumor in China. Most gastric cancer patients are already in the locally advanced stage when they seek medical treatment. Radical surgery is the main treatment for gastric cancer. The quality control of postoperative perioperative management is of great significance in improving the surgical treatment effect and the quality of life of patients. This article systematically summarizes seven aspects, including diet and nutrition management, antimicrobial drug management, pain management, prophylactic anticoagulation management, airway management, postoperative complication management, and discharge and follow-up management, establishes clear quality standards, and achieves the goals of reducing postoperative complications, standardizing perioperative medication use, reducing hospitalization time and costs, thereby reducing patient burden and improving the economic and social benefits of medical institutions.

Astragaloside IV-mediated inhibition of oxidative stress by upregulation of ghrelin in type 2 diabetes-induced cognitive impairment

This study is to observe the upregulation effect of astragaloside IV on ghrelin in diabetic cognitive impairment (DCI) rats and to investigate the pathway in prevention and treatment by reducing oxidative stress. The DCI model was induced with streptozotocin (STZ) in conjunction with a high-fat and high-sugar diet and divided into three groups: model, low-dose (40 mg/kg), and high-dose (80 mg/kg) astragaloside IV. After 30 days of gavage, the learning and memory abilities of rats, as well as their body weight and blood glucose levels, were tested using the Morris water maze and then detection of insulin resistance, SOD activity, and serum MDA levels. The whole brain of rats was sampled for hematoxylin-eosin and Nissl staining to observe pathological changes in the hippocampal CA1 region. Immunohistochemistry was used to detect ghrelin expression in the hippocampal CA1 region. A Western blot was used to determine changes in GHS-R1α/AMPK/PGC-1α/UCP2. RT-qPCR was used to determine the levels of ghrelin mRNA. Astragaloside IV reduced nerve damage, increased superoxide dismutase (SOD) activity, decreased MDA levels, and improved insulin resistance. Ghrelin levels and expression increased in serum and hippocampal tissues, and ghrelin mRNA levels increased in rat stomach tissues. According to Western blot, it increased the expression of the ghrelin receptor GHS-R1α and upregulated the mitochondrial function associated-protein AMPK-PGC-1α-UCP2. Astragaloside IV increases ghrelin expression in the brain to reduce oxidative stress and delay diabetes-induced cognitive impairment. It may be related to the promotion of ghrelin mRNA levels.

Evaluation of immunogenicity of gene-deleted and subunit vaccines constructed against the emerging pseudorabies virus variants

BACKGROUND

Pseudorabies (PR) (also called Aujeszky's disease, AD) is a serious infectious disease affecting pigs and other animals worldwide. The emergence of variant strains of pseudorabies virus (PRV) since 2011 has led to PR outbreaks in China and a vaccine that antigenically more closely matches these PRV variants could represent an added value to control these infections.

METHODS

The objective of this study was to develop new live attenuated and subunit vaccines against PRV variant strains. Genomic alterations of vaccine strains were based on the highly virulent SD-2017 mutant strain and gene-deleted strains SD-2017ΔgE/gI and SD-2017ΔgE/gI/TK, which constructed using homologous recombination technology. PRV gB-DCpep (Dendritic cells targeting peptide) and PorB (the outer membrane pore proteins of N. meningitidis) proteins containing gp67 protein secretion signal peptide were expressed using the baculovirus system for the preparation of subunit vaccines. We used experimental animal rabbits to test immunogenicity to evaluate the effect of the newly constructed PR vaccines.

RESULTS

Compared with the PRV-gB subunit vaccine and SD-2017ΔgE/gI inactivated vaccines, rabbits (n = 10) that were intramuscularly vaccinated with SD-2017ΔgE/gI/TK live attenuated vaccine and PRV-gB + PorB subunit vaccine showed significantly higher anti-PRV-specific antibodies as well as neutralizing antibodies and IFN-γ levels in serum. In addition, the SD-2017ΔgE/gI/TK live attenuated vaccine and PRV-gB + PorB subunit vaccine protected (90-100%) rabbits against homologous infection by the PRV variant strain. No obvious pathological damage was observed in these vaccinated rabbits.

CONCLUSIONS

The SD-2017ΔgE/gI/TK live attenuated vaccine provided 100% protection against PRV variant challenge. Interestingly, the subunit vaccines with gB protein linked to DCpep and PorB protein as adjuvant may also be a promising and effective PRV variant vaccine candidate.

Correlation between serum cytokines and clinicopathological features in patients with drug-induced liver injury

Objectives: Changes in serum levels of cytokines have been proposed as possible biological markers of tissue damage, including drug-induced liver injury (DILI). Here, we aimed to screen cytokine markers that have guiding significance for the degree of inflammation of DILI. Patients and methods: 54 patients with DILI were retrospectively analyzed as the experimental group, and 14 healthy subjects were randomly selected as the control group. A total of 20 cytokines were detected by using a cytokine protein antibody chip, and differentially expressed proteins were screened. Results: There were significant differences in serum cytokines between DILI patients and healthy controls. Compared with the control group, the DILI group expressed 11 differential proteins. IL-8, TNF RII, TNFα, TNF RI, MIP-1β, MIP-1α, and IL-1β were differentially expressed in DILI patients with different degrees of inflammation from G1 to G4. MIG, IL-12p40, and IL-10 were differentially expressed in the higher degree of inflammation groups (G2, G3, and G4 groups). Tissue inhibitor of metalloproteinases-1 (TIMP-1) was differentially expressed in the group with the highest inflammation degree (G4 group). Chemokine C-C motif ligand 1 (I-309) was only differentially expressed in the lowest inflammation group (G1 group). Conclusion: The changes and differential expression of specific cytokine levels were helpful for evaluating different degrees of inflammation of DILI.

[Investigation of an acute hydrogen sulfide mixture gas poisoning in a confined space]

Hydrogen sulphide poisoning is an acute poisoning event that occurs frequently in summer. A case of acute hydrogen sulphide poisoning in a confined space in August 2018 was investigated and clinical data were analyzed. This is a typical case of acute hydrogen sulfide gas poisoning in a confined space. The main cause of the accident is the lack of occupational protection and illegal rescue. Among the 5 patients, 3 died, 1 patient had long-term sequelae of nervous system damage such as cortical blindness, and 1 patient was cured.

Associations between Certain Polymorphisms in Proinflammatory Cytokines and Predisposition of Alzheimer's Disease: A Meta-Analysis

BACKGROUND

Functional gene polymorphisms of proinflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-18 (IL-18) may contribute to the onset and development of Alzheimer's disease (AD), but the relationships between these polymorphisms and predisposition of AD remain controversial.

OBJECTIVES

This meta-analysis was conducted to more robustly assess relationships between TNF-α/IL-6/IL-8/IL-18 polymorphisms and predisposition of AD by pooling the findings of relevant studies.

METHODS

A comprehensive literature searching was performed in PubMed, Embase, Web of Science, Wanfang, and CNKI databases, and 63 studies were found to be eligible for quantitative analyses.

RESULTS

The pooled meta-analysis results showed that genotypic frequencies of TNF-α rs1800629, IL-6 rs1800795, IL-8 rs4073, and IL-18 rs187238 polymorphisms among AD cases and controls of Asian ethnicity differed significantly. But, we did not observe such genotypic frequencies differences in Caucasians.

CONCLUSIONS

This meta-analysis suggests that TNF-α rs1800629, IL-6 rs1800795, IL-8 rs4073, and IL-18 rs187238 polymorphisms may affect predisposition of AD in Asians, but not in Caucasians.

[Disinfection By-products in Drinking Water and Their Control Strategies: A Review]

Disinfection by-products(DBPs) are secondary pollutants generated by the reaction of disinfectants with organic or inorganic precursors during drinking water disinfection. DBPs have received considerable global attention due to their carcinogenic, teratogenic, and mutagenic characteristics. Focusing on drinking water, this paper introduces the main classification and research history of DBPs, and then summarizes the concentration levels of common DBPs in drinking water, and DBPs regulatory compliance in global drinking water standards. Further, the control strategies for DBPs in drinking water, including source control, process control, DBPs removal and integrated control are introduced together with the advantages and disadvantages. Finally, a summary and review of the current level and future trends of DBPs research in China are presented with the proposed control strategies. On the one hand, when evaluating the control effect of a process or technology, the DBPs concentration and comprehensive toxicity should be considered; on the other hand, in order to realize the efficient control of DBPs in drinking water, the focus should be on the integrated methods coupling different DBPs control methods.

[Establishment and validation of a nomogram to predict overall survival of patients with gastric neuroendocrine neoplasms]

Objective: To establish a novel nomogram to predict overall survival of patients with gastric neuroendocrine neoplasms (g-NEN). Methods: A case control study was conducted. Clinicopathological and follow-up data of patients with g-NEN who were treated in two academic medical centers in Southern China between July 2008 and June 2018 were retrospectively collected, including 174 patients from Sun Yat-sen University Cancer Center and 102 patients from the First Affiliated Hospital of Sun Yat-sen University. Univariate survival analysis using Kaplan-Meier method and multivariate analysis using Cox regression were performed to identify prognostic factors. A nomogram was subsequently established based on prognostic factors. Harrell's concordance index (C-index), receiver operating characteristic (ROC) curve, calibration curve and decision curve analysis (DCA) were used to verify the performance of the model according to differentiation, calibration and clinical utility. Results: A total of 276 patients were enrolled in the study, of whom 189 patients were male and 87 were female. The age at diagnosis was below 60 years old in 150 patients and 60 years or older in 126 patients. There were patients diagnosed with gastric neuroendocrine carcinoma (g-NEC) and 101 patients with gastric neuroendocrine tumor (g-NET). The number of patients with primary tumor locating at upper, middle and lower parts of stomach was 131, 98 and 47, respectively. As for TNM stage, 72 patients were categorized as stage I, 26 patients stage II, 93 patients stage III, and 85 patients stage IV. Univariate analysis indicated that age, pathological type, primary site, Ki-67 index, T stage, N stage, and M stage were associated with overall survival of g-NEN patients (all P<0.05). Multivariate regression analysis testified that high Ki-67 index, advanced T stage and advanced M stage were independent prognostic factors (all P<0.05). The C-index of the nomogram was 0.806 (95%CI: 0.769-0.863). The calibration curve of the nomogram showed that the predicted survival rate was consistent with the actual survival rate in g-NEN patients. The ROC curves and DCA showed that the nomogram had better differentiation and clinical utility than the American Joint Committee on Cancer (AJCC) 8th TNM staging system (the area under the ROC curve was 0.862 vs. 0.792). Conclusion: The first nomogram to predict overall survival of patients with g-NEN is established and verified in this study, which provides individual prediction of 3-year overall survival rate and is applicable to both g-NET and g-NEC patients.

Autophagy is involved in the replication of H9N2 influenza virus via the regulation of oxidative stress in alveolar epithelial cells

Background

Oxidative stress is an important pathogenic factor in influenza A virus infection. It has been found that reactive oxygen species induced by the H9N2 influenza virus is associated with viral replication. However, the mechanisms involved remain to be elucidated.

Methods

In this study, the role of autophagy was investigated in H9N2 influenza virus-induced oxidative stress and viral replication in A549 cells. Autophagy induced by H9N2 was inhibited by an autophagy inhibitor or RNA interference, the autophagy level, viral replication and the presence of oxidative stress were detected by western blot, TCID50 assay, and Real-time PCR. Then autophagy and oxidative stress were regulated, and viral replication was determined. At last, the Akt/TSC2/mTOR signaling pathways was detected by western blot.

Results

Autophagy was induced by the H9N2 influenza virus and the inhibition of autophagy reduced the viral titer and the expression of nucleoprotein and matrix protein. The blockage of autophagy suppressed the H9N2 virus-induced increase in the presence of oxidative stress, as evidenced by decreased reactive oxygen species production and malonaldehyde generation, and increased superoxide dismutase 1 levels. The changes in the viral titer and NP mRNA level caused by the antioxidant, N-acetyl-cysteine (NAC), and the oxidizing agent, H₂O₂, confirmed the involvement of oxidative stress in the control of viral replication. NAC plus transfection with Atg5 siRNA significantly reduced the viral titer and oxidative stress compared with NAC treatment alone, which confirmed that autophagy was involved in the replication of H9N2 influenza virus by regulating oxidative stress. Our data also revealed that autophagy was induced by the H9N2 influenza virus through the Akt/TSC2/mTOR pathway. The activation of Akt or the inhibition of TSC2 suppressed the H9N2 virus-induced increase in the level of LC3-II, restored the decrease in the expression of phospho-pAkt, phospho-mTOR and phospho-pS6 caused by H9N2 infection, suppressed the H9N2-induced increase in the presence of oxidative stress, and resulted in a decrease in the viral titer.

Conclusion

Autophagy is involved in H9N2 virus replication by regulating oxidative stress via the Akt/TSC2/mTOR signaling pathway. Thus, autophagy maybe a target which may be used to improve antiviral therapeutics.

Genomic characterization and phylogenetic evolution of the SARS-CoV-2

 The coronavirus disease 2019 (COVID-19) starting on 12 December 2019 in Wuhan, China, caused 7,885,123 cases including 431,835 deaths by 14 Jun 2020 all over the world. Here we report the genomic characterization and phylogenetic evolution of coronavirus SARS-CoV-2 causing COVID-19. The SARS-CoV-2 and other coronavirus genomes were obtained from GISAID and GenBank. The genomes were annotated and potential genetic recombination was investigated. Phylogenetic analysis was conducted and used to determine the evolutionary history of the virus and to elucidate the origin of the virus. The analysis had revealed that SARS-CoV-2 possessed a similar genomic organization to bat-SARS-like-CoV collected in China. The genome sequences of SARS-CoV-2 were very similar, showing 99.6-100% sequence identity. Notably, SARS-CoV-2 was closely related (with 88% identity) to bat-SARS-like coronavirus, but was more distant from SARS-CoV (about 79%) and MERS-CoV (about 50%). Phylogenetic tree of the complete viral genome showed that the virus clustered with bat SARS-like coronavirus. The results of the similarity between SARS-CoV-2 and related viruses did not identify any potential genomic recombination events. Therefore, it seems that the SARS-CoV-2 might be originally hosted by bats, and might have been transmitted to humans via intermediate hosts of currently unknown wild animal(s). Finally, based on the wide spread of SARS-CoV in their natural reservoirs, future studies should focus more on surveillance of coronaviruses, and measures against the domestication and consumption of wild animals should be implemented. Keywords: coronavirus; SARS coronavirus; SARS-CoV-2; genomic characterization; phylogenetic evolution.

[Clinical features and prognostic factors in adult acute myeloid leukemia patients with FLT3-ITD and CEBPA gene co-mutation]

目的

研究FLT3-ITD及CEBPA双等位基因突变(CEBPAdm)共突变成人急性髓系白血病(AML)患者的临床特征及预后。

方法

对2016年1月至2018年9月就诊于郑州大学第一附属医院的初治成人AML患者的临床资料进行回顾性研究，比较分析其临床特点及预后。基因突变检测采用直接测序法。

结果

①接受基因突变检测的非M₃且资料完整患者599例，检出FLT3-ITD基因突变阳性（FLT3-ITD⁺）且CEBPAdm阳性（CEBPAdm⁺）患者19例（A组），FLT3-ITD⁺且CEBPAdm⁻患者84例（B组），FLT3-ITD⁻且CEBPAdm⁺患者95例（C组），未检出任何已知基因突变患者70例（D组），共计268例。②A、B、C、D四组间性别、PLT、FAB分型、诱导治疗方案、融合基因突变情况差异均无统计学意义（P值均>0.05）；而发病年龄、初诊时WBC、HGB含量、外周血原始幼稚细胞比例、骨髓原始幼稚细胞比例差异均有统计学意义（P值均<0.05）。组间两两比较，A组较B、C、D组性别、年龄、HGB含量、PLT、FAB分型差异无统计学意义（P值均>0.05）。A组初诊时外周血WBC、外周血原始幼稚细胞比例、首疗程诱导治疗后微小残留病（MRD）水平高于B、C、D各组。③A、B、C、D组首疗程化疗后完全缓解（CR₁）率分别为50.0%、32.4%、59.8%、39.0%（P=0.003），复发率分别为55.6%、50.0%、21.1%、40.0%（P<0.001），中位总生存时间分别为6.25、3.0、15.5、10.5个月（P<0.001），中位无进展生存时间分别为5.0、4.0、10.0、6.7个月（P=0.032）。

结论

FLT3-ITD及CEBPAdm共突变成人AML患者初诊时外周血WBC高，外周血原始幼稚细胞比例高，首疗程诱导化疗后MRD水平高，CR₁率低，复发率高，中位总生存时间、中位无进展生存时间短，预后不佳。

Molecular characterization and pathogenesis of H9N2 avian influenza virus isolated from a racing pigeon

H9N2 avian influenza viruses (AIVs) can cross species barriers and expand from birds tomammals and humans. It usually leads to economic loss for breeding farms and poses a serious threat to human health.This study investigated the molecular characteristics of H9N2 AIV isolated from a racing pigeon and its pathogenesis in BALB/c mice and pigeons. Phylogenetic analysis indicated that the H9N2 virus belonged to the Ck/BJ/94-like lineage, and acquired multiple specific amino acid substitutions that might contribute to viral transmission from birds to mammals and humans. A pathogenesis study showed that both mice and pigeons infected with H9N2 virus showed clinical signs and mortality. The H9N2 viruses efficiently replicated in mice and pigeons. In our study, high levels of viral shedding were detected in pigeons, but the infection was not transmitted to co-housed pigeons. Histopathological examination revealed the presence of inflammatory responses in the infected mice and pigeons. Immunohistochemical analysis showed the presence of H9N2 virus in multiple organs of the infected mice and pigeons. Moreover, the infected mice and pigeons demonstrated significant cytokine/chemokine production. Our results showed that the H9N2 virus can infect mice and pigeons, and can not be transmitted between pigeons through direct contact.

Identification of a functional nuclear localization signal in 3Dpol/3CD of duck hepatitis A virus 1

The nuclear localization signals (NLS) were usually composed of basic residues (K and R) and played an important role in delivery of genomes and structural protein into nucleus. In this research, we identified that 3D^pol/3CD entered into nucleus during viral propagation of duck hepatitis A virus type 1 (DHAV-1). To investigate the reason that 3D^pol/3CD entered into nucleus, the amino acid sequence of 3CD was analyzed through NLS Mapper program. The basic region ¹⁷PRKTAYMRS²⁵ was subsequently proved to be a functional NLS to guide 3D^pol/3CD into nucleus. ¹⁸R, ¹⁹K and ²⁴R were found essential for maintaining the nuclear targeting activity, and exchange between ²⁴R and ²⁴K had no impact on cellular localization of 3D^pol. Since the entry of 3D^pol/3CD into nucleus was essential for shutoff of host cell transcription and maintaining the viral propagation of picornavirus numbers, our study provided new insights into the mechanism of DHAV-1 propagation.

Autophagy is involved in the acute lung injury induced by H9N2 influenza virus

Influenza A virus usually leads to economic loss to breeding farms and pose a serious threat to human health. Virus infecting tissues directly and influenza virus-induced excessive production of inflammatory factors play the key role in pathogenesis of the disease, but the mechanism is not well clarified. Here, the role of autophagy was investigated in H9N2 influenza virus-triggered inflammation. The results showed that autophagy was induced by H9N2 virus in A549 cells and in mice. Inhibiting autophagy by an autophagy inhibitor (3-methyladenine, 3-MA) or knockdown of Atg5(autophagy-related gene) by Atg5 siRNA significantly suppressed H9N2 virus replication, H9N2 virus-triggered inflammatory cytokines and chemokines, including IL-1β, TNF-α, IL-8, and CCL5 in vitro and in vivo, and suppressed H9N2 virus-triggered acute lung injury as indicated as accumulative mortality of mice, inflammatory cellular infiltrate and interstitial edema, thickening of the alveolar walls in mice lung tissues, increased inflammatory cytokines and chemokines, increased W/D ratio in mice. Moreover, autophagy mediated inflammatory responses through Akt-mTOR, NF-κB and MAPKs signaling pathways. Our data showed that autophagy was essential in H9N2 influenza virus-triggered inflammatory responses, and autophagy could be target to treat influenza virus-caused lung inflammation.

Identification of a novel missense eya4 mutation causing autosomal dominant non‑syndromic hearing loss in a chinese family

The aim of this study was to identify the novel missense eya4 mutation which cause autosomal dominant non syndromic hearing loss In a Chinese family. Hearing loss is the most common sensory deficit in humans, but the middle-frequency sensorineural hearing loss (MFSNHL) is rare among hereditary non-syndromic hearing loss, and EYA4 is one of the genes reported to be associated with MFSNHL. A genetic analysis of a Chinese family with autosomal dominant non‑syndromic progressive hearing impairment was conducted and assessed. Targeted exome sequencing, conducted using DNA samples of an affected member in this family, revealed a novel heterozygous missense mutation c.1855T&gt;G in exon 20 of EYA4, causing amino-acid (aa) substitution Gly for Trp at a conserved position aa-619. The p.W619G mutation related to hearing loss in this Chinese family was validated by Sanger sequencing. Bioinformatic analysis confirmed the pathogenic effects of this mutation. We identified the novel missense mutation c.1855T&gt;G (p.W619G) in EYA4 causing autosomal dominant non-syndromic hearing impairment in the selected Chinese family.

The Functional Role of the 3' Untranslated Region and Poly(A) Tail of Duck Hepatitis A Virus Type 1 in Viral Replication and Regulation of IRES-Mediated Translation

The duck hepatitis A virus type 1 (DHAV-1) is a member of Picornaviridae family, the genome of the virus contains a 5′ untranslated region (5′ UTR), a large open reading frame that encodes a polyprotein precursor and a 3′ UTR followed by a poly(A) tail. The translation initiation of virus proteins depends on the internal ribosome-entry site (IRES) element within the 5′ UTR. So far, little information is known about the role of the 3′ UTR and poly(A) tail during the virus proliferation. In this study, the function of the 3′ UTR and poly(A) tail of DHAV-1 in viral replication and IRES-mediated translation was investigated. The results showed that both 3′ UTR and poly(A) tail are important for maintaining viral genome RNA stability and viral genome replication. During DHAV-1 proliferation, at least 20 adenines were required for the optimal genome replication and the virus replication could be severely impaired when the poly (A) tail was curtailed to 10 adenines. In addition to facilitating viral genome replication, the presence of 3′ UTR and poly(A) tail significantly enhance IRES-mediated translation efficiency. Furthermore, 3′ UTR or poly(A) tail could function as an individual element to enhance the DHAV-1 IRES-mediated translation, during which process, the 3′ UTR exerts a greater initiation efficiency than the poly(A)₂₅ tail.

C-terminal 20 residues of ORF3 protein of duck circovirus genotype 2 regulates the nuclear localization and inhibits apoptotic activity of ORF3 protein

Duck circovirus (DuCV) is divided into genotypes 1 and 2. The DuCV ORF3 protein is a newly identified viral protein with apoptotic activity. In this study, the differences in the gene sequences, subcellular localization, and apoptotic activities of the ORF3 proteins of DuCV genotypes 1 and 2 were analyzed. A T-to-A point mutation at nucleotide 236 (T236A) in the ORF3 gene sequence of DuCV genotype 1 was observed, which generates a premature stop codon (TAG) and resulted in a truncated ORF3 protein. The ORF3 protein of DuCV genotype 2 is 20 amino acids longer at its C-terminus than the truncated ORF3 protein of genotype 1. A variant monopartite-type nuclear localization signal (RRLRTCNCRACRTLK) was identified within the C-terminal region of the ORF3 protein of DuCV genotype 2, which is essential for the nuclear localization of the protein. The 20 C-terminal residues of the DuCV genotype 2 ORF3 protein also inhibits the apoptotic activity of the protein. Our findings provide insight into the biological and functional characteristics of the DuCV ORF3 protein.

Roles of p38 MAPK in the regulation of the inflammatory response to swine influenza virus-induced acute lung injury in mice

Swine influenza virus (SIV), one of the most important zoonotic agents, is associated with major public health concerns. The current study was conducted to investigate the role of p38 mitogen-activated protein kinase (p38 MAPK) in the regulation of the inflammatory response to acute lung injury (ALI) induced by SIV of H9N2 subtype (H9N2-SIV) in mice. For this purpose, BALB/c mice were intranasally infected with 20 LD(50) of H9N2-SIV (infected group), while non-infected mice served as control (control group). To assess the effect of p38 MAPK, its specific inhibitor SB203580 was employed followed by SIV infection (SB group). At various times after infection, mouse lungs were subjected to pathological and histological observations and detection of inflammatory cytokines tumor necrosis factor α (TNF)-α, interleukin (IL)-1β, IL-6, and IL-10 and phosphorylated p38 MAPK. The obtained results showed obvious inflammatory responses, injury and raised levels of inflammatory cytokines and phosphorylated p38 MAPK in the lungs of virus-infected mice. In the mice inoculated with the virus alone, the level of phosphorylated p38 MAPK increased from day 2 and peaked at day 6 post infection (p.i.). However, SB203580 caused lower increases in inflammatory cytokines and phosphorylated p38 MAPK and a milder lung injury. These findings indicate that the activation of p38 MAPK upregulated the inflammatory responses to H9N2-SIV-induced ALI, increased its severity and promoted the production of inflammatory cytokines.

The complete mitochondrial genome of the ice pigeon (Columba livia breed ice)

The ice pigeon is a breed of fancy pigeon developed over many years of selective breeding. In the present work, we report the complete mitochondrial genome sequence of ice pigeon for the first time. The total length of the mitogenome was 17,236 bp with the base composition of 30.2% for A, 24.0% for T, 31.9% for C, and 13.9% for G and an A-T (54.2 %)-rich feature was detected. It harbored 13 protein-coding genes, 2 ribosomal RNA genes, 22 transfer RNA genes and 1 non-coding control region (D-loop region). The arrangement of all genes was identical to the typical mitochondrial genomes of pigeon. The complete mitochondrial genome sequence of ice pigeon would serve as an important data set of the germplasm resources for further study.

N-acetyl-l-cystine (NAC) protects against H9N2 swine influenza virus-induced acute lung injury

The antioxidant N-acetyl-l-cysteine (NAC) had been shown to inhibit replication of seasonal human influenza A viruses. Here, the effects of NAC on H9N2 swine influenza virus-induced acute lung injury (ALI) were investigated in mice. BALB/c mice were inoculated intranasally with 10⁷ 50% tissue culture infective doses (TCID₅₀) of A/swine/HeBei/012/2008/(H9N2) viruses with or without NAC treatments to induce ALI model. The result showed that pulmonary inflammation, pulmonary edema, MPO activity, total cells, neutrophils, macrophages, TNF-α, IL-6, IL-1β and CXCL-10 in BALF were attenuated by NAC. Moreover, our data showed that NAC significantly inhibited the levels of TLR4 protein and TLR4 mRNA in the lungs. Pharmacological inhibitors of TLR4 (E5564) exerted similar effects like those determined for NAC in H9N2 swine influenza virus-infected mice. These results suggest that antioxidants like NAC represent a potential additional treatment option that could be considered in the case of an influenza A virus pandemic.

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NAC protects against H9N2 swine influenza virus-induced acute lung injury (ALI).

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NAC protects against acute lung injury by inactivation of TLR4.

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Eritoran (E5564), a TLR4 antagonist, also protects against acute lung injury.

ChIP-seq analysis of histone H3K9 trimethylation in peripheral blood mononuclear cells of membranous nephropathy patients

Membranous nephropathy (MN), characterized by the presence of diffuse thickening of the glomerular basement membrane and subepithelial in situ immune complex disposition, is the most common cause of idiopathic nephrotic syndrome in adults, with an incidence of 5-10 per million per year. A number of studies have confirmed the relevance of several experimental insights to the pathogenesis of human MN, but the specific biomarkers of MN have not been fully elucidated. As a result, our knowledge of the alterations in histone methylation in MN is unclear. We used chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) to analyze the variations in a methylated histone (H3K9me3) in peripheral blood mononuclear cells from 10 MN patients and 10 healthy subjects. There were 108 genes with significantly different expression in the MN patients compared with the normal controls. In MN patients, significantly increased activity was seen in 75 H3K9me3 genes, and decreased activity was seen in 33, compared with healthy subjects. Five positive genes, DiGeorge syndrome critical region gene 6 (DGCR6), sorting nexin 16 (SNX16), contactin 4 (CNTN4), baculoviral IAP repeat containing 3 (BIRC3), and baculoviral IAP repeat containing 2 (BIRC2), were selected and quantified. There were alterations of H3K9me3 in MN patients. These may be candidates to help explain pathogenesis in MN patients. Such novel findings show that H3K9me3 may be a potential biomarker or promising target for epigenetic-based MN therapies.

[Effects of xinfuli granule on cardiomyocyte apoptosis in rats with dilated heart failure induced by adriamycin]

OBJECTIVE

To investigate the effects of Xinfuli Granule (XG) on cardiomyocyte apoptosis in rats with adriamycin-induced dilated cardiomyopathy (DCM).

METHODS

Seventy-two male SD rats were randomly divided into 6 groups, i.e., the normal control group, the model group, the irbesartan group, the low dose XG group, the medium dose XG group, and the high dose XG group. The DCM heart failure rat model was established using peritoneal injection of ADR. Equal volume of normal saline was injected to those in the normal control group, once per week for 6 consecutive weeks. The medication was started from the 5th week by gastrogavage. XG was dispensed into 0.5 g/mL suspension with distilled water. The XG was administered at the daily dose of 0.675 g/kg, 1.350 g/kg, and 2.700 g/kg to those in the low dose XG group, the medium dose XG group, and the high dose XG group, respectively. Irbesartan was administered to rats in the irbesartan group at the daily dose of 50 mg/kg. Equal volume of normal saline was administered to those in the normal control group and the model group by gastrogavage, once in the morning for 4 consecutive weeks. Myocardial apoptosis was measured by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL), and the expressions of the Bcl-2 and Bax protein of cardiomyocytes were measured by immunohistochemical assay.

RESULTS

Compared with the normal control group, the cardiomyocyte apoptosis rate and Bax expression level obviously increased, but the expression of Bcl-2 and the Bcl-2/Bax ratio decreased significantly in the model group (P < 0.05). Compared with the model group, the expression of Bax and the Bcl-2/Bax ratio increased significantly in the high dose XG group and the irbesartan group (P < 0.01). The Bax expression level obviously decreased in all groups except the normal control group (P < 0.01).

CONCLUSIONS

XG could obviously attenuate cardiomyocyte apoptosis in the adriamycin-induced DCM rats, and reverse the occurrence and development of heart reconstruction. The underlying mechanism might be related to regulating and controlling the expressions of Bax and Bcl-2.

Controlling growth rate anisotropy for formation of continuous ZnO thin films from seeded substrates

Solution-processed zinc oxide (ZnO) thin films are promising candidates for low-temperature-processable active layers in transparent thin film electronics. In this study, control of growth rate anisotropy using ZnO nanoparticle seeds, capping ions, and pH adjustment leads to a low-temperature (90 ° C) hydrothermal process for transparent and high-density ZnO thin films. The common 1D ZnO nanorod array was grown into a 2D continuous polycrystalline film using a short-time pure solution method. Growth rate anisotropy of ZnO crystals and the film morphology were tuned by varying the chloride (Cl(-)) ion concentration and the initial pH of solutions of zinc nitrate and hexamethylenetetramine (HMTA), and the competitive adsorption effects of Cl(-) ions and HMTA ligands on the anisotropic growth behavior of ZnO crystals were proposed. The lateral growth of nanorods constituting the film was promoted by lowering the solution pH to accelerate the hydrolysis of HMTA, thereby allowing the adsorption effects from Cl(-) to dominate. By optimizing the growth conditions, a dense ∼100 nm thickness film was fabricated in 15 min from a solution of [Cl(-)]/[Zn(2+)] = 1.5 and pH=  4.8 ± 0.1. This film shows >80% optical transmittance and a field-effect mobility of 2.730 cm(2) V(-1) s(-1) at zero back-gate bias.

Hydrogen sensor based on Au and YSZ/HgO/Hg electrode for in situ measurement of dissolved H2 in high-temperature and -pressure fluids

Gold as a hydrogen-sensing electrode for in situ measurement of dissolved H2 in aqueous solutions under extreme conditions is reported. The dissolved H2 sensor, constructed with a Au-based sensing element and coupled with a YSZ/HgO/Hg electrode, is well suited for determining dissolved H2 concentrations of aqueous fluids at elevated temperatures and pressures. The Au electrode is made of Au wire mounted in a quartz bar, which can be pressurized and heated in the high-pressure and -temperature conditions. The Au-YSZ sensor has been tested for its potential response to the concentrations of dissolved H2 in fluids by using a flow-through reactor at high temperatures up to 400 degrees C and pressures to 38 MPa. Good sensitivity and linear response between the hydrogen concentrations in the fluids and the H2 sensor potentials are reported for hydrogen gas in the concentration range of 0.1-0.001 M H2 in aqueous fluids at temperatures up to 340 degrees C and 30 MPa. Nernstian response of the cell potential to dissolved H2 in fluids was determined at 340 degrees C and 30 MPa, described as follows: DeltaE = 0.9444 + 0. 0603 log m H2 The experimental results indicate that the Au-YSZ/HgO/Hg cell can be used to measure the solubility of H2 in aqueous fluid at temperatures and pressures near to the critical state of water. Thus, this type of Au hydrogen sensor could be easily used for in situ measurement of H2 in hydrothermal fluids in a high-pressure vessel, or at midocean ridge, due to its structure of compression resistance.

The way and therapeutic efficacy of traditional Chinese medicine treatments based on the differentiation of symptoms and signs on gastrointestinal function disorder after cardiovascular surgery

AIM: To study the way and summarize the therapeutic effect of syndrome differentiation-based Chinese medicine treatments on gastrointestinal function disorder after cardiovascular surgery.

METHODS: This study included a group of 80 patients with gastrointestinal function disorder after cardiovascular surgery, who were treated by traditional Chinese medicine based on the differentiation of symptoms and signs.

RESULTS: Of the 80 patients, 46 showed excellent efficacy and 31 exhibit general efficacy. No effectiveness was found in 3 patients. The total effective rate of the treatment by traditional Chinese medicine was 96.25%.

CONCLUSION: Treatment based on the differentiation of symptoms and signs can improve the gastrointestinal function of patients after cardiovascular surgery and reduce the in-hospital time.

[Effects of shading light quality at seedling stage on the photosynthesis and growth of ginger]

With different color plastic films as shading materials, this paper studied the effects of shading light quality at seedling stage on the growth and photosynthesis of ginger. The results showed that shading with green or blue film induced the greatest chlorophyll content in ginger leaves, followed by shading with white film, and red film. In parallel, the photosynthetic rate under green film-shading was the highest, being 14.9 micromol x m(-2) x s(-1) in the 4th leaves, which was 5.7%, 10.4%, and 18.3% higher than that under white, red, and blue film-shading, respectively. After removing the films at vigorous growth stage, the photosynthetic rate became larger, and its change pattern in different shading treatments was similar to that at seedling stage. No significant differences in the chlorophyll content of young leaves were observed among the shading treatments, except the low chlorophyll content under red film-shading. In contrast, the chlorophyll content in low position leaves under blue and red film-shading was lower than that under green and white film-shading. In the whole growth period, the plants under blue film-shading were higher in height and with thinner stem and lesser shoot, compared with those shaded with other color films. The fresh mass of root, stem, leaf, and rhizome decreased in the order of green, white, red, and blue film-shading, and the yields at harvesting stage were 57,000, 53,709, 51,487, and 48,712 kg x hm(-2), respectively, illustrating that shading with green film at seedling stage could increase the leaf photosynthesis, plant growth, and yield of ginger.

Improved human T-cell responses against synthetic HLA-0201 analog peptides derived from the WT1 oncoprotein

Wilms tumor protein 1 (WT1) is a transcription factor overexpressed in several types of leukemia and solid tumors. For this reason, WT1 is an attractive target for immunotherapy. Four peptide nonamers from WT1 have been identified by others to generate a WT1-specific cytotoxic response in the context of human leukocyte antigen (HLA)-A0201 and A2402. However, as WT1 is a self-antigen, breaking tolerance is a potential obstacle to vaccination. Here, we use a strategy to circumvent tolerance by designing synthetic immunogenic analog peptides that could crossreact to the native peptides (a heteroclitic response). A number of synthetic peptides derived from nonamer sequences of the WT1 protein were designed in which single amino-acid substitutions were introduced at HLA-A0201 major histocompatibility complex (MHC)-binding positions. Several of new peptides could stabilize MHC class I A0201 molecules better than native sequences. Some analogs were also able to elicit WT1-specific T-cell recognition and cytotoxic T-cell lymphocytes more effectively than native sequences. Importantly, T cells stimulated with the new analogs crossreacted with the native WT1 peptide sequence and were able to kill HLA-matched chronic myeloid leukemia cell lines. In conclusion, analog heteroclitic WT1 peptides with increased immunogenicity can be synthesized and are potential cancer vaccine candidates.

[A latex agglutination test for detection of hemagglutinin serum antibodies to H5 avian influenza virus in chicken]

A Latex Agglutination Test (LAT) was developed for quick detection of hemagglutinin serum antibodies of H5 Avian Influenza Virus (AIV) in chicken. Recombinant hemagglutinin protein of H5 AIV were obtained and purified, then HA protein were covalently linked to carboxylated polyethylene latex beads by EDAC. The sensitisation condition such as ionic strength of the diluting mixture pH, concentration, antigen, the times of linking were optimized. 126 fresh serum after vaccination were detected by this LAT and HI simultaneously, the result show that sensitivity for the LAT was 87.03%, the specificity was 88.8%, the coincidence rate of both methods was 87.30%. The result indicated that this LAT method can be used for quick detection of serum antibodies and epidemiological study of H5 AIV.

[Expression of hemagglutinin of avian influenza virus (AIV) and its application in diagnosis of AIV H9 subtype]

In order to differently diagnose avian influenza virus (AIV) subtypes, the HA gene of AIV H9 subtype was cloned, expressed and utilized in an enzyme-linked immunoad sorbent assay (ELISA). HA gene (1683bp) of H9N2 AIV was amplified by RT-PCR from a strain of field isolated H9N2 AIV, and its identity was confirmed by sequencing. The HA gene was subcloned into prokaryotic expression vector pGEX-KG with its secretion signal sequence removed. The expressed HA-GST fusion protein in E. coli BL21 was characterized by SDS-PAGE and western blotting analysis as a 90kD protein with immunogenicity. The fusion protein was present primarily in inclusion bodies and was purified via denaturation and renenaturation. The HA-GST fusion protein was used to establish an indirect ELISA for the detection of antibodies to H9 subtypes of AIV. The assay has 91.57% specificity to H9 AIV, 92.31% sensitivity and excellent reduplication. It could be used to differently detect antibodies to H9 AIV.

[Construction of an eukaryotic expression plasmid for short peptides used in DNA immunization]

AIM

To construct a plasmid which efficiently express short peptides in DNA immunization.

METHODS

The plasmid containing peptide-expressing cassette (PEC) was constructed and its effect in DNA immunization was investigated, using a DHBV B cell epitope as the short peptide. The peptide in vitro was detected by DOT-EIA. The BALB/c mice were immunized with the empty plasmid or the recombinant plasmid, and the specific antibodies against the epitope in the sera of the mice were determined by ELISA.

RESULTS

The plasmid containing peptide-expressing cassette (PEC) was successfully constructed. Recombinant epitope-based plasmid could efficiently express the short peptide in vitro and induce immune response against it in DNA immunization.

CONCLUSION

The constructed vector provides highly efficient short peptide expression in DNA immunization.

Effects of 2-hydroxypropyl-beta-cyclodextrin on pharmacokinetics of digoxin in rabbits and humans

Considering the narrow therapeutic index of digoxin and the low range between the safe and toxic serum concentrations of this drug, to evaluate the relative bioavailability of tablets and oral solution is necessary. The pharmacokinetic properties of digoxin after oral administration of its hydroxypropyl-beta-cyclodextrin (HPCD) inclusion complex to rabbits and human volunteers were investigated in comparison with those of commercially available tablets. The aqueous solubility of digoxin was enhanced by HPCD for about 2000 times at HPCD concentration of 50% (w/v). But in a human bioavailability study no significant difference was observed in the extent of absorption (AUC(0-t)) and Cmax between the two formulations. Time to reach peak was significantly shorter for the solution than for the tablets (p < 0.01). The pharmacokinetic results from the rabbit study were similar to human studies and no significant difference was observed for AUC, Cmax and Tmax. As the bioavailability of both tablets and solution is equivalent HPCD based oral digoxin solution could serve as an alternative to tablets.

Differential susceptibility of naïve versus cloned CD4+ T cells to antigen-specific and MHC-restricted anergy induction

T cell anergy has been successfully induced under different conditions in cloned CD4(+) T cells, but induction of T cell anergy in vivo has been difficult and controversial. Due to the low frequency of naturally occurring T cell population with specificity to a defined antigen, it is very difficult to study anergy of naïve T cells without prior in vivo priming which complicates the interpretation of experimental data. To solve this problem, we adopted the HNT-TCR transgenic mice which have homogeneous antigen specific CD4(+) T cell population. In this study, we generated an influenza virus hemagglutinin (HA) peptide-specific CD4(+) T cell clone from the HNT-TCR transgenic mice and induced anergy using APCs which were treated with the crosslinker, ECDI (1-ethyl-3-3(3-dimethylaminopropyl) carbodiimide). The proliferative response of the cloned or freshly purified naïve CD4(+) transgenic T cells after treatment with ECDI-treated APCs and the HA peptide antigen was monitored as the index of anergy induction. The results showed that anergy was successfully induced in the cloned HNT-TCR transgenic CD4(+) T cells. It was determined that the induced anergy was antigen- and MHC-specific. By contrast, anergy was not observed in freshly purified naïve CD4(+) transgenic T cells under the same conditions. The results suggest that naïve CD4(+) T cells may have different anergy inducing requirements, or that cloned CD4(+) T cells may have certain priming or in vitro cloning artifact which makes them more susceptible to anergy induction. We propose that induction of T cell anergy may depend on the T cell growth, activation and differentiation state or cloning conditions. The results from the present study may have important implications for the study of the mechanism(s) underlying T cell anergy induction in vivo and for applications of immune tolerance based therapy.

Breast-feeding among women exposed to polybrominated biphenyls in Michigan

In the early 1970s, the largest industrial accident in the United States resulted in widespread contamination of the food supply in Michigan with polybrominated biphenyls (PBBs). The chemical similarity of PBBs to compounds implicated as endocrine disruptors has raised the question of whether PBBs could affect the reproductive system. In the present analysis we examine the relation between serum measurements of PBBs and the frequency and duration of lactation. Persons who lived on or received food from farms exposed to PBBs were enrolled in a registry by the Michigan Department of Public Health. Female members of the cohort were invited to participate in a telephone survey of reproductive outcomes. The three outcomes of interest in the present analysis were a) the decision to breast-feed (yes/no); b) the duration, in months, of breast-feeding as the main source of nutrition; and c) the total duration, in months, of breast-feeding. None of the three outcomes was significantly associated with serum PBB levels, even after controlling for maternal age, previous history of breast-feeding, body mass index, maternal education, household income, history of smoking in the year before pregnancy, consumption of alcohol during the first trimester of pregnancy, history of thyroid disorder, gestational age of the infant in weeks, time to pregnancy, and year of birth.

Direct inhibition of the hexose transporter GLUT1 by tyrosine kinase inhibitors

The facilitative hexose transporter GLUT1 is a multifunctional protein that transports hexoses and dehydroascorbic acid, the oxidized form of vitamin C, and interacts with several molecules structurally unrelated to the transported substrates. Here we analyzed in detail the interaction of GLUT1 with a group of tyrosine kinase inhibitors that include natural products of the family of flavones and isoflavones and synthetic compounds such as the tyrphostins. These compounds inhibited, in a dose-dependent manner, the transport of hexoses and dehydroascorbic acid in human myeloid HL-60 cells, in transfected Chinese hamster ovary cells overexpressing GLUT1, and in normal human erythrocytes, and blocked the glucose-displaceable binding of cytochalasin B to GLUT1 in erythrocyte ghosts. Kinetic analysis of transport data indicated that only tyrosine kinase inhibitors with specificity for ATP binding sites inhibited the transport activity of GLUT1 in a competitive manner. In contrast, those inhibitors that are competitive with tyrosine but not with ATP failed to inhibit hexose uptake or did so in a noncompetitive manner. These results, together with recent evidence demonstrating that GLUT1 is a nucleotide binding protein, support the concept that the inhibitory effect on transport is related to the direct interaction of the inhibitors with GLUT1. We conclude that predicted nucleotide-binding motifs present in GLUT1 are important for the interaction of the tyrosine kinase inhibitors with the transporter and may participate directly in the binding transport of substrates by GLUT1.

[Study on the release mechanism of fenoprofen calcium from hydrophillic sustained-release matrix]

AIM

To study the release mechanism of fenoprofen calcium (FC) from hydroxypropylmethylcellulose (HPMC) matrices.

METHODS

The release of FC and the erosion properties of hydrophillic matrices containing HPMC was examined at different paddle speed. The release mechanism of FC was further confirmed by evaluating the n value in Peppas equation.

RESULTS

The results indicate that the release of FC and the erosion of matrices exhibit zero order kinetic equation, and it exhibits line relationship between them.

CONCLUSION

In the first 40 min, FC mainly released by diffusion and erosion from HPMC matrix, while it was controlled by the rate of tablet erosion after 50 min.

Age at menarche and tanner stage in girls exposed in utero and postnatally to polybrominated biphenyl

Accidental contamination of the Michigan food chain with polybrominated biphenyls (PBBs) led to the exposure of more than 4,000 individuals in 1973. Because PBB exposure is suspected to disrupt endocrine function, we assessed pubertal development in females 5-24 years of age (N = 327) who were exposed to PBB in utero and, in many cases, through breastfeeding. We estimated in utero PBB exposure using maternal serum PBB measurements taken after exposure (1976-1979) and extrapolated to time of pregnancy using a model of PBB decay. We found that breastfed girls exposed to high levels of PBB in utero (> or =7 parts per billion) had an earlier age at menarche (mean age = 11.6 years) than breastfed girls exposed to lower levels of PBB in utero (mean age = 12.2-12.6 years) or girls who were not breastfed (mean age = 12.7 years). This association persisted after adjustment for potential confounders (menarche ratio = 3.4, 95% confidence interval = 1.3-9.0). Perinatal PBB exposure was associated with earlier pubic hair stage in breastfed girls, but little association was found with breast development. The associations observed here lend support to the hypothesis that pubertal events may be affected by pre- and postnatal exposure to organohalogens.

K-ras and p53 in pancreatic cancer: association with medical history, histopathology, and environmental exposures in a population-based study

Pancreatic cancer is a highly fatal cancer with few identified risk factors. Increased risk of pancreatic cancer in tobacco smokers and among diabetic patients is well established, and some reports have suggested associations with coffee consumption and occupational exposure to organochlorines. At present, there is little information regarding the possible association of these risk factors with the known genetic alterations found in pancreatic cancers, such as activation of the K-ras oncogene and inactivation of the p53 tumor suppressor gene. Knowledge of such relationships may help to understand the molecular pathways of pancreatic tumorigenesis. We investigated the association between these molecular defects and risk factors for pancreatic cancer in 61 newly diagnosed patients identified through an ongoing study of pancreatic cancer in the San Francisco Bay Area. Interview information was obtained regarding environmental exposures, medical history, and demographic factors. Serum levels of dichlorodiphenyltrichloroethylene (DDE) and polychlorinated biphenyls were available on a subset of 24 patients. Tumor blocks were located from local hospitals and used for K-ras mutational analysis at codon 12 and for p53 protein immunohistochemistry. The molecular analyses were facilitated through the use of laser capture microdissection, which provides a reliable method to obtain almost pure populations of tumor cells. Mutations in K-ras codon 12 were found in 46 (75%) of 61 pancreatic cancers. A prior diagnosis of diabetes was significantly associated with K-ras negative tumors (P = 0.002, Fisher's exact test). The absence of this mutation was also associated with increased serum levels of DDE, although this association was not statistically significant (P = 0.16, Wilcoxon's test). There was no difference in polychlorinated biphenyl levels between the K-ras wild-type and mutant groups. Immunohistochemical staining for p53 protein did not differ by patient characteristics or clinical history, but significant associations were found with poor glandular differentiation (P = 0.002, chi2 trend test), severe nuclear atypia (P = 0.0007, chi2 trend test), and high tumor grade (P = 0.004, chi2 trend test). Our results are suggestive of the presence of K-ras codon 12 mutation-independent tumorigenesis pathways in patients with prior diabetes and possibly in patients with higher serum levels of DDE. Our results also support a role for the p53 tumor suppressor protein in the maintenance of genomic integrity.

Bis(1,5-diazacyclooctane-N,N')nickel(II) dibromide

The crystal structure of the title complex, [Ni(C(6)H(14)N(2))(2)]Br(2), consists of discrete [Ni(C(6)H(14)N(2))(2)](2+) cations and bromide counter-anions. The Ni(II) ion is at the center of symmetry and is four-coordinated by four nitrogen donors of the mesocyclic ligand 1,5-diazacyclooctane (DACO) [Ni-N 1.935 (2)-1.937 (2) A]. The coordination geometry of Ni(II) can be considered as square planar and both DACO ligands take the boat-chair conformation. The bromide anions are hydrogen bonded with the nitrogen donors of the ligands to form a macrocycle-like ring system.

Varying coordination modes and magnetic properties of copper(II) complexes with diazamesocyclic ligands by altering additional donor pendants on 1,5-diazacyclooctane

A series of new diazamesocyclic ligands based on a diazamesocycle, 1,5-diazacyclooctane (DACO), functionalized by additional donor groups--1,5-bis(N-1-methylimidazol-2-ylmethyl)-1,5- diazacyclooctane (L1), 1-(2-hydroxybenzyl)-1,5-diazacyclooctane (HL2), 1,5-bis(2-hydroxybenzyl)-1,5-diazacyclooctane (H2L3), and 1-(N-1-methylimidazol-2-ylmethyl)-1,5-diazacyclooctane (L4)--and their Cu(II) complexes have been synthesized and characterized. Single-crystal X-ray diffraction analysis of the four Cu(II) complexes revealed that L1 forms a five-coordinate mononuclear complex, HL2 a N3- mu-bridged binuclear complex, H2L3 an oxygen mu-bridged trinuclear complex, and L4 a one-dimensional zigzag coordination polymeric complex with Cu(II). [CuL1ClO4](ClO4) (I): a = 12.194(2) A, b = 13.351(3) A, c = 14.473(3) A, beta = 107.10(3) degrees, Z = 4. [CuL2(N3)]2 (II): a = 8.1864(6) A, b = 18.141(2) A, c = 9.3307(7) A, beta = 103.662(6) degrees, Z = 2. [Cu3(L3)2Cl2] (III): a = 10.7296(13) A, b = 13.7707(17) A, c = 13.5523(17) A, beta = 106.350(3) degrees, Z = 2. ([CuL4Cl]2ClO4) infinity (IV): a = 7.279(1) A, b = 23.695(5) A, c = 19.308(4) A, beta = 100.28(3) degrees, Z = 8. All four complexes crystallize in the monoclinic crystal system with the P2(1)/c space group, and each Cu(II) center coordinated with DACO is pentacoordinated with a distorted square-pyramidal or trigonal-bipyrimidal coordination environment. In complex IV, the binuclear cation unit [CuL4Cl]2(2+) constitutes the fundamental building block of an infinite alternating zigzag chain structure, and the binuclear unit contains two types of geometries around the Cu(II) centers: the Cu(1) center is a distorted square-pyramidal environment, while the Cu(2) is a distorted trigonal-bipyramidal coordination environment. To the best of our knowledge, this is the first Cu(II) complex of a diazamesocyclic ligand with an infinite polymeric structure. The magnetic properties of complexes II, III, and IV have been investigated by variable-temperature magnetic susceptibility measurements in the solid state. The obtained parameters are 2J = 2.06 cm-1 (II), -345.56 cm-1 (III), and -2.60 cm-1 (IV), which differ greatly from ferromagnetic to weak and strong antiferromagnetic coupling. These results unequivocally indicate that the nature of the pendant arms is a key factor governing the structure and properties of the complexes; therefore, the coordination modes and properties of the metal complexes of a diazamesocycle can be controlled by altering the pendant donors on it. Magneto-structural correlation has been precisely analyzed, and the solution properties of these complexes have also been described.

Determinants of polybrominated biphenyl serum decay among women in the Michigan PBB cohort

Accidental contamination of the food chain in Michigan in 1973 with polybrominated biphenyls (PBBs) led to the establishment of a registry of exposed individuals in 1976. Serum was collected and analyzed for PBB at the time of enrollment and for targeted studies in the following years. We used the archived PBB data to study the elimination of PBB and to identify factors associated with elimination. A total of 380 women >= 16 years of age who had an initial PBB level of 2 ppb and at least two serum samples drawn when they were not pregnant were included in the analysis. The mean initial PBB level was 20.9 ppb (median 4) and mean time between the first and last measurement was 4.2 years (range 0.5-11.1). PBB was assumed to reach equilibrium in the body before substantial amounts were eliminated and before the first serum measurements were taken; therefore, the entire body was modeled as a single compartment for PBB with exponential decay. Subject-specific decay rate estimates were regressed on predictor variables including initial age, body mass index (BMI), smoking history, breast-feeding duration, and parity. In women with an initial PBB level < 10 ppb, the median half-life was 12.9 years; in those with > 10 ppb, the median half-life was 28.7 years. Decay was significantly slower among women with an initial BMI at or above the median (BMI >= 23). The calculated half-life values are estimates of decay and can be used to estimate body burden of PBB at various points in time other than at the time of serum collection.

Pancreatic cancer and serum organochlorine levels

Occupational exposure to p,p'-dichlorodiphenyltrichloroethane (DDT) has been associated with increased pancreatic cancer risk. We measured organochlorine levels in serum obtained at the study enrollment from 108 pancreatic cancer cases and 82 control subjects aged 32-85 years in the San Francisco Bay Area between 1996 and 1998. Cases were identified using rapid case-ascertainment methods; controls were frequency-matched to cases on age and sex via random digit dial and random sampling of Health Care Financing Administration lists. Serum organochlorine levels were adjusted for lipid content to account for variation in the lipid concentration in serum between subjects. Median concentrations of p,p'-dichlorodiphenyldichloroethylene (DDE, 1290 versus 1030 ng/g lipid; P = 0.05), polychlorinated biphenyls (PCBs; 330 versus 220 ng/g lipid; P<0.001), and transnonachlor (54 versus 28 ng/g lipid; P = 0.03) were significantly greater among cases than controls. A significant dose-response relationship was observed for total PCBs (P for trend <0.001). Subjects in the highest tertile of PCBs (> or =360 ng/g lipid) had an odds ratio (OR) of 4.2 [95% confidence interval (CI) = 1.8-9.4] compared to the lowest tertile. The OR of 2.1 for the highest level of p,p'-DDE (95% CI = 0.9-4.7) diminished (OR = 1.1; 95% CI = 0.4-2.8) when PCBs were included in the model. Because pancreatic cancer is characterized by cachexia, the impact of this on the serum organochlorine levels in cases is difficult to predict. One plausible effect of cachexia is bioconcentration of organochlorines in the diminished lipid pool, which would lead to a bias away from the null. To explore this, a sensitivity analysis was performed assuming a 10-40% bioconcentration of organochlorines in case samples. The OR associated with PCBs remained elevated under conditions of up to 25% bioconcentration.

El Niño and the related phenomenon Southern Oscillation (ENSO): the largest signal in interannual climate variation

El Niño and the related phenomenon Southern Oscillation (ENSO) is the strongest signal in the interannual variation of ocean-atmosphere system. It is mainly a tropical event but its impact is global. ENSO has been drawing great scientific attention in many international research programs. There has been an observational system for the tropical ocean, and scientists have known the climatologies of the upper ocean, developed some theories about the ENSO cycle, and established coupled ocean-atmosphere models to give encouraging predictions of ENSO for a 1-year lead. However, questions remain about the physical mechanisms for the ENSO cycle and its irregularity, ENSO-monsoon interactions, long-term variation of ENSO, and increasing the predictive skill of ENSO and its related climate variations.