Protein covalently bound to minus-strand DNA intermediates of duck hepatitis B virus.

Analysis of duck hepatitis B viral DNA by gel electrophoresis, Southern blotting, and binding to benzoylated naphthoylated DEAE-cellulose showed that a protein is bound to the minus-strand virion DNA as well as to the full-length single strand, minus-strand species, and minus-strand DNA intermediates isolated from replicating complexes present in infected duck liver. By utilizing a modified dideoxynucleotidyl sequencing method, it was shown that the protein is covalently bound to the smallest detectable growing strands (ca. 30 bases) and that minus-strand synthesis begins at a unique site. These results support the notion that the protein may function as a primer for synthesis of the minus-strand DNA.     

中国的炭疽杆菌DNA分型及其地理分布

炭疽广泛分布于中国各地,特别是西部地区,并经常造成人畜疾病,在一项合作研究中,用多位点VNTR分析（MLVA）对从1952-1998年自中国主要地理流行区域分离的病人,病畜和土壤等来源的炭疽杆菌进行了基因分型,MLVA分析结果揭示了21种新的基因型,其等位基因组合在以前世界范围分离物的研究中未曾发现,此外,分离物的分群显示,A3b组是地理上最广泛分布的基因组,说明该组可能是中国的“地方流行株”。而来自古丝绸之路重要贸易中心新疆的大量分离株其基因型特别分散。     

Systems analysis of primary Sjögren's syndrome pathogenesis in salivary glands identifies shared pathways in human and a mouse model

Bone tissue has an exceptional quality to regenerate to native tissue in response to injury. However, the fracture repair process requires mechanical stability or a viable biological microenvironment or both to ensure successful healing to native tissue. An improved understanding of the molecular and cellular events that occur during bone repair and remodeling has led to the development of biologic agents that can augment the biological microenvironment and enhance bone repair. Orthobiologics, including stem cells, osteoinductive growth factors, osteoconductive matrices, and anabolic agents, are available clinically for accelerating fracture repair and treatment of compromised bone repair situations like delayed unions and nonunions. Preclinical and clinical studies using biologic agents like recombinant bone morphogenetic proteins have demonstrated an efficacy similar or better than that of autologous bone graft in acute fracture healing. A lack of standardized outcome measures for comparison of biologic agents in clinical fracture repair trials, frequent off-label use, and a limited understanding of the biological activity of these agents at the bone repair site have limited their efficacy in clinical applications.     

Reduced IgG anti-small nuclear ribonucleoprotein autoantibody production in systemic lupus erythematosus patients with positive IgM anti-cytomegalovirus antibodies

Introduction

In rheumatoid arthritis (RA), synovial fluid (SF) contains a large number of neutrophils that contribute to the inflammation and destruction of the joints. The SF also contains granulocyte-macrophage colony-stimulating factor (GM-CSF), which sustains viability of neutrophils and activates their functions. Using proteomic surveillance, we here tried to elucidate the effects of GM-CSF on neutrophils.

Methods

Neutrophils stimulated by GM-CSF were divided into four subcellular fractions: cytosol, membrane/organelle, nuclei, and cytoskeleton. Then, proteins were extracted from each fraction and digested by trypsin. The produced peptides were detected using matrix-assisted laser desorption ionisation-time-of-flight mass spectrometry (MALDI-TOF MS).

Results

We detected 33 peptide peaks whose expression was upregulated by more than 2.5-fold in GM-CSF stimulated neutrophils and identified 11 proteins out of the 33 peptides using MALDI-TOF/TOF MS analysis and protein database searches. One of the identified proteins was neutrophil gelatinase-associated lipocalin (NGAL). We confirmed that the level of NGAL in SF was significantly higher in patients with RA than in those with osteoarthritis. We next addressed possible roles of the increased NGAL in RA. We analysed proteome alteration of synoviocytes from patients with RA by treatment with NGAL in vitro. We found that, out of the detected protein spots (approximately 3,600 protein spots), the intensity of 21 protein spots increased by more than 1.5-fold and the intensity of 10 protein spots decreased by less than 1 to 1.5-fold as a result of the NGAL treatment. Among the 21 increased protein spots, we identified 9 proteins including transitional endoplasmic reticulum ATPase (TERA), cathepsin D, and transglutaminase 2 (TG2), which increased to 4.8-fold, 1.5-fold and 1.6-fold, respectively. Two-dimensional electrophoresis followed by western blot analysis confirmed the upregulation of TERA by the NGAL treatment and, moreover, the western blot analysis showed that the NGAL treatment changed the protein spots caused by post-translational modification of TERA. Furthermore, NGAL cancelled out the proliferative effects of fibroblast growth factor (FGF)-2 and epidermal growth factor (EGF) on chondrocytes from a patient with RA and proliferative effect of FGF-2 on chondrosarcoma cells.

Conclusions

Our results indicate that GM-CSF contributes to the pathogenesis of RA through upregulation of NGAL in neutrophils, followed by induction of TERA, cathepsin D and TG2 in synoviocytes. NGAL and the upregulated enzymes may therefore play an important role in RA.     

Frequent coexistence of anti-topoisomerase I and anti-U1RNP autoantibodies in African American patients associated with mild skin involvement: a retrospective clinical study

Introduction  

The presence of anti-topoisomerase I (topo I) antibodies is a classic scleroderma (SSc) marker presumably associated with a unique clinical subset. Here the clinical association of anti-topo I was reevaluated in unselected patients seen in a rheumatology clinic setting.     

T cell lines with dual specificity for strong Mls and H-2 determinants

To examine the relationship of T cell specificity for Mls vs H-2 determinants, BALB/c (H-2d,Mlsb)(d,b) T cells were stimulated repeatedly in vitro with H-2-compatible, Mls-incompatible DBA/2(d,a) stimulators. This line of T cells gave strong mixed-lymphocyte reactions to the priming Mlsa determinants but, in addition, gave appreciable responses to various foreign H-2 determinants. When this T cell line was subsequently stimulated over a period of 2 mo with Mlsa-negative cells of a particular foreign H-2 haplotype, e.g., H-2k, the cells gave high responses to H-2k determinants but only very low responses to third-party H-2 determinants. Significantly, the cells retained high reactivity for Mlsa determinants. In other experiments, BALB/c T cells positively selected to Mlsa,d-negative H-2-incompatible stimulator cells retained high reactivity for Mlsa determinants. The implications of these findings are discussed.     

E-box元件修饰端粒酶核心启动子序列及体外转录活性分析

人类端粒酶启动子(hTERT启动子)在肿瘤基因治疗中的有效性已经得到了证实. 然而,hTERT启动子有限的肿瘤靶向转录活性困扰着它的临床应用.早期研究已经揭示,核心hTERT启动子上的-34位E-box元件与该启动子的肿瘤靶向转录活性有关.为进一步探索核心hTERT启动子序列3′端富余E-box元件是否能提高启动子的肿瘤靶向转录能力,用化学合成方法在野生型hTERT(WT-hTERT)核心启动子片段(编码蛋白起始子ATG上游-268 bp～-10 bp)的3′端接入3个E-box序列, 构建成修饰型hTERT(Mod-hTERT)启动子. 然后,分别用WT-hTERT和Mod-hTERT启动子去调控增强型绿色荧光蛋白(EGFP)及荧光素酶报告基因在293FT、HepGⅡ、SGC7901、U2OS、以及原代培养人成纤维细胞(PHF)中表达. 结果表明, 在Mod-hTERT启动子的各实验组细胞中,能够在端粒酶阳性的293FT、HepGⅡ及 SGC7901细胞组中观测到EGFP的表达,而在端粒酶阴性的U2OS及PHF细胞组中没有观测到EGFP的表达;在端粒酶阳性的293FT、HepGⅡ和SGC7901细胞株中,Mod-hTERT启动子调控下的荧光素酶活性要高于WT-hTERT启动子组（P＜0.01）; 而在端粒酶阴性的U2OS细胞组中,Mod-hTERT启动子调控下的荧光素酶活性则低于WT-hTERT启动子组（P＜0.01); 在PHF细胞组中,Mod-hTERT启动子组与WT-hTERT启动子组的荧光素酶活性差异不显著(P＞0.05).研究提示,在3′端增加E-box元件可以提高核心hTERT启动子序列的肿瘤靶向转录活性.     

Species loss of stoneflies (Plecoptera) in the Czech Republic during the 20th century

1. Rapid expansion and intensification of anthropogenic activities in the 20th century has caused profound changes in freshwater assemblages. Unfortunately, knowledge of the extent and causes of species loss (SL) is limited due to the lack of reliable historical data. An unusual data set allows us to compare changes in the most sensitive of aquatic insect orders, the Plecoptera, at some 170 locations in the Czech Republic between two time periods, 1955–1960 and 2006–2010. Historical data (1890–1911) on assemblages of six lowland rivers allow us to infer even earlier changes. 2. Regional stonefly diversity decreased in the first half of the 20th century. Streams at lower altitudes lost a substantial number of species, which were never recovered. In the second half of the century, large‐scale anthropogenic pressure caused SL in all habitats, leading to a dissimilarity of contemporary and previous assemblages. The greatest changes were found at sites affected by organic pollution and a mixture of organic pollution and channelisation or impoundment. Colonisation of new habitats was observed in only three of the 80 species evaluated. 3. Species of moderate habitat specialisation and tolerance to organic pollution were most likely to be lost. Those with narrow specialisations in protected habitats were present in both historical and contemporary collections. 4. Contemporary assemblages are the consequence of more than a 100 years of anthropogenic impacts. In particular, streams at lower altitude and draining intensively exploited landscapes host a mere fragment of the original species complement. Most stonefly species are less frequently present than before, although their assemblages remain almost intact in near‐natural mountain streams. Our analyses demonstrate dramatic restriction of species ranges and, in some cases, apparent changes in altitudinal preference throughout the area.     

MicroRNAs in systemic rheumatic diseases

MicroRNAs (miRNAs) are endogenous, non-coding, single-stranded RNAs about 21 nucleotides in length. miRNAs have been shown to regulate gene expression and thus influence a wide range of physiological and pathological processes. Moreover, they are detected in a variety of sources, including tissues, serum, and other body fluids, such as saliva. The role of miRNAs is evident in various malignant and nonmalignant diseases, and there is accumulating evidence also for an important role of miRNAs in systemic rheumatic diseases. Abnormal expression of miRNAs has been reported in autoimmune diseases, mainly in systemic lupus erythematosus and rheumatoid arthritis. miRNAs can be aberrantly expressed even in the different stages of disease progression, allowing miRNAs to be important biomarkers, to help understand the pathogenesis of the disease, and to monitor disease activity and effects of treatment. Different groups have demonstrated a link between miRNA expression and disease activity, as in the case of renal flares in lupus patients. Moreover, miRNAs are emerging as potential targets for new therapeutic strategies of autoimmune disorders. Taken together, recent data demonstrate that miRNAs can influence mechanisms involved in the pathogenesis, relapse, and specific organ involvement of autoimmune diseases. The ultimate goal is the identification of a miRNA target or targets that could be manipulated through specific therapies, aiming at activation or inhibition of specific miRNAs responsible for the development of disease.