Characterization and expression of a novel alternatively spliced human angiopoietin-2

Angiopoietin-2 (Ang2) is a naturally occurring antagonist of angiopoietin-1 (Ang1) that competes for binding to the Tie2 receptor and blocks Ang1-induced Tie2 autophosphorylation during vasculogenesis. Using the polymerase chain reaction, we isolated a cDNA encoding a novel shorter form of Ang2 from human umbilical vein endothelial cell cDNA and have designated it angiopoietin-2(443) (Ang2(443)), because it contains 443 amino acids. Part of the coiled-coil domain (amino acids 96-148) is absent in Ang2(443) because of alternative splicing of the gene. Like Ang2, recombinant Ang2(443) expressed in COS-7 cells is secreted as a glycosylated homodimeric protein. Recombinant Ang2(443) binds to the Tie2 receptor but does not induce Tie2 phosphorylation. Pre-occupation of Ang2(443) on Tie2 inhibits Ang1 or Ang2 binding and inhibits Ang1-induced phosphorylation. Expression of Ang2(443) mRNA is detectable in primary endothelial cells, several nonendothelial tumor cell lines, and primary tumor tissues. Interestingly, two cervical carcinoma cell lines express relatively moderate levels of Ang2(443) mRNA and protein. Macrophages express mainly Ang2 mRNA, but the expression of Ang2(443) mRNA is temporarily up-regulated during macrophage differentiation. These results suggest that Ang2(443) is a functional antagonist of Ang1 and could be an important regulator of angiogenesis during some tumorigenic and inflammatory processes.     

Distribution of sarcophytol A in soft coral of the Sarcophyton genus

The distribution of sarcophytol-A in the Sarcophyton genus was investigated in seven samples belonging to S. glaucum (3 samples), S. infundibulifurme (2 samples), S. crassocaule (1 sample) and S. trocheliophorum (1 sample) that were collected on Ishigaki Island in Okinawa Prefecture. Sarcophytol-A was present in one sample each of S. glaucum and S. infundibulifurme. This study indicates that the composition of cembranoids in the Sarcophyton genus is not related with the respective species, but with the individual samples collected.     

HIV-1 Balances the Fitness Costs and Benefits of Disrupting the Host Cell Actin Cytoskeleton Early after Mucosal Transmission

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High-depth sequencing of over 750 genes supports linear progression of primary tumors and metastases in most patients with liver-limited metastatic colorectal cancer

BackgroundColorectal cancer with metastases limited to the liver (liver-limited mCRC) is a distinct clinical subset characterized by possible cure with surgery. We performed high-depth sequencing of over 750 cancer-associated genes and copy number profiling in matched primary, metastasis and normal tissues to characterize genomic progression in 18 patients with liver-limited mCRC.ResultsHigh depth Illumina sequencing and use of three different variant callers enable comprehensive and accurate identification of somatic variants down to 2.5% variant allele frequency. We identify a median of 11 somatic single nucleotide variants (SNVs) per tumor. Across patients, a median of 79.3% of somatic SNVs present in the primary are present in the metastasis and 81.7% of all alterations present in the metastasis are present in the primary. Private alterations are found at lower allele frequencies; a different mutational signature characterized shared and private variants, suggesting distinct mutational processes. Using B-allele frequencies of heterozygous germline SNPs and copy number profiling, we find that broad regions of allelic imbalance and focal copy number changes, respectively, are generally shared between the primary tumor and metastasis.ConclusionsOur analyses point to high genomic concordance of primary tumor and metastasis, with a thick common trunk and smaller genomic branches in general support of the linear progression model in most patients with liver-limited mCRC. More extensive studies are warranted to further characterize genomic progression in this important clinical population.

Electronic supplementary material

The online version of this article (doi:10.1186/s13059-015-0589-1) contains supplementary material, which is available to authorized users.     

Conceptualization And Manifestation Of Depression In An Asian Context: Formal Construction And Validation Of A Children’S Depression Scale In Singapore

Understanding that the conceptualization and manifestation of depression vary across cultures, in a preliminary study, Koh and colleagues (2002) identified a cultural model and a prototype measure of depression for Asian children. The present study sought to provide further examination of the initially identified conceptualization, manifestation, and measurement of depression in Asian children. Involving a community sample of 442 Singaporean Chinese children (6 to 12 years old), a culturally salient factor, Negative Social Self, was established to constitute part of depression, in addition to three universally recognized factors: Negative Affect and Cognitive Dysfunction, Loss of Interest, and Psychosomatic Manifestations. The Asian Children Depression Scale (ACDS) and Negative Social Self (NSS) were found to be positively related to hopelessness and negatively related to self-esteem, subjective well-being, and control-related beliefs, establishing support for convergent validity. Notably, NSS was found to account for significant incremental validity over that of the universally recognized factors in predicting most of the above-mentioned variables, supporting its added value as a factor of depression in Asian children. The results suggested that the ACDS and the culturally salient dimension reflect the phenomenological experiences and manifestations of depression in Asian children.     

Development of a method for reconstruction of crowded NMR spectra from undersampled time-domain data

NMR is a unique methodology for obtaining information about the conformational dynamics of proteins in heterogeneous biomolecular systems. In various NMR methods, such as transferred cross-saturation, relaxation dispersion, and paramagnetic relaxation enhancement experiments, fast determination of the signal intensity ratios in the NMR spectra with high accuracy is required for analyses of targets with low yields and stabilities. However, conventional methods for the reconstruction of spectra from undersampled time-domain data, such as linear prediction, spectroscopy with integration of frequency and time domain, and analysis of Fourier, and compressed sensing were not effective for the accurate determination of the signal intensity ratios of the crowded two-dimensional spectra of proteins. Here, we developed an NMR spectra reconstruction method, “conservation of experimental data in analysis of Fourier” (Co-ANAFOR), to reconstruct the crowded spectra from the undersampled time-domain data. The number of sampling points required for the transferred cross-saturation experiments between membrane proteins, photosystem I and cytochrome b ₆ f, and their ligand, plastocyanin, with Co-ANAFOR was half of that needed for linear prediction, and the peak height reduction ratios of the spectra reconstructed from truncated time-domain data by Co-ANAFOR were more accurate than those reconstructed from non-uniformly sampled data by compressed sensing.     

Bidirectional Association between Self-Reported Hypertension and Gout: The Singapore Chinese Health Study

It has been hypothesized that the association between hypertension and gout is bidirectional, however, few studies have examined this in a prospective cohort. We analyzed data from the Singapore Chinese Health Study (SCHS) follow-up I (1999–2004) and II (2006–2010) interviews, when both physician-diagnosed hypertension and gout were self-reported. We included participants with data for both follow-up interviews and who were free of heart disease, stroke and cancer at follow-up I. The analysis of hypertension and risk of gout included 31,137 participants when prevalent gout cases were excluded, while the analysis of gout and risk of hypertension included 20,369 participants when prevalent hypertension cases were excluded. Cox proportional hazards models were used to estimate multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs). The mean age at follow-up I was 60.1 (SD 7.3) years, and the average follow-up was 6.8 (SD 1.4) years. In the analysis of hypertension and risk of gout, 682 incident cases were identified. Compared to normotensive participants, hypertensive patients had an88% increased risk of developing gout (HR 1.88; 95% CI 1.61–2.21). In the parallel analysis, 5,450 participants reported to have newly diagnosed hypertension during follow-up. Compared to participants without gout, those with gout had an18% increased risk of developing hypertension (HR 1.18; 95% CI 1.02–1.37). The bidirectional association was stronger in normal weight adults compared to overweight/obese individuals (P _interaction = 0.06 and 0.04, respectively). The hypertension to gout association was stronger in women compared to men (P _interaction = 0.04), while the gout to hypertension association was evident in women but not in men (P _interaction = 0.02). In conclusion, our results suggest that the hypertension-gout association is bidirectional in this cohort of Singapore Chinese adults. The potential interactions of the bidirectional association with obesity and sex deserve further investigations.     

Radiographic Structural Damage Is Worse in the Dominant than the Non-Dominant Hand in Individuals with Early Rheumatoid Arthritis

Objective

The relationship between mechanical stress and radiographic progression in rheumatoid arthritis (RA) is unclear. The assumption is that mechanical stress is greater in the dominant hand. Therefore, the aim of the present study was to compare the presence and progression of erosions and joint space narrowing (JSN) in the dominant and non-dominant hand.

Methods

Data from 194 patients recently diagnosed with seropositive RA, and with hand radiographs taken at the time of diagnosis and at 2-year follow-up, were analyzed retrospectively. Radiographs were scored using the van der Heijde-modified Sharp Score (HSS) method. Each joint group within each hand was rated separately by two independent examiners in a double-blinded manner.

Results

One hundred and ninety-four patients were enrolled (80% female, 88% positive rheumatoid factor, 92% positive anti-citrullinated protein antibody, and 95.4% right-handed). The baseline, follow-up erosion and JSN HSS were significantly higher in the dominant hand than in the non-dominant hand. The annual rate of radiographic progression was also higher in the dominant hand. The erosive progression in the wrist joints varied significantly according to handedness, but the erosion in the proximal interphalangeal joints and metacarpophalangeal joints was similar in both hands. The radiographic progression was associated with the dominant hand, an abnormal baseline C-reactive protein level, and joint damage at baseline. There was no significant difference in bone mineral density between the right and left hands.

Conclusion

Radiological damage was worse and progressed faster in the dominant hand, suggesting that mechanical stress is associated with radiographic joint damage in early and active RA.