Historical isolation and contemporary gene flow drive population diversity of the brown alga Sargassum thunbergii along the coast of China.

BACKGROUND: Long-term survival in isolated marginal seas of the China coast during the late Pleistocene ice ages is widely believed to be an important historical factor contributing to population genetic structure in coastal marine species. Whether or not contemporary factors (e.g. long-distance dispersal via coastal currents) continue to shape diversity gradients in marine organisms with high dispersal capability remains poorly understood. Our aim was to explore how historical and contemporary factors influenced the genetic diversity and distribution of the brown alga Sargassum thunbergii, which can drift on surface water, leading to long-distance dispersal. RESULTS: We used 11 microsatellites and the plastid RuBisCo spacer to evaluate the genetic diversity of 22 Sargassum thunbergii populations sampled along the China coast. Population structure and differentiation was inferred based on genotype clustering and pairwise F ST and allele-frequency analyses. Integrated genetic analyses revealed two genetic clusters in S. thunbergii that dominated in the Yellow-Bohai Sea (YBS) and East China Sea (ECS) respectively. Higher levels of genetic diversity and variation were detected among populations in the YBS than in the ECS. Bayesian coalescent theory was used to estimate contemporary and historical gene flow. High levels of contemporary gene flow were detected from the YBS (north) to the ECS (south), whereas low levels of historical gene flow occurred between the two regions. CONCLUSIONS: Our results suggest that the deep genetic divergence in S. thunbergii along the China coast may result from long-term geographic isolation during glacial periods. The dispersal of S. thunbergii driven by coastal currents may facilitate the admixture between southern and northern regimes. Our findings exemplify how both historical and contemporary forces are needed to understand phylogeographical patterns in coastal marine species with long-distance dispersal.

Hidden diversity and phylogeographic history provide conservation insights for the edible seaweed Sargassum fusiforme in the Northwest Pacific.

Understanding the evolutionary processes that have created diversity and the genetic potential of species to adapt to environmental change is an important premise for biodiversity conservation. Herein, we used mitochondrial trnW-L and cox3 and plastid rbcL-S data sets to analyze population genetic variation and phylogeographic history of the brown alga Sargassum fusiforme, whose natural resource has been largely exterminated in the Asia-Northwest Pacific in the past decades. Phylogenetic trees and network analysis consistently revealed three major haplotype groups (A, B, and C) in S. fusiforme, with A and B distributed in the Japan-Pacific coast. Group C consisted of three subgroups (C1, C2, and C3) which were distributed in the Sea of Japan, the Yellow-Bohai Sea, and East China Sea, respectively. Isolation-with-migration (IM a) analysis revealed that the three groups diverged approximately during the mid-Pleistocene (c. 756-1,224 ka). Extended Bayesian skyline plots (EBSP) showed that groups A and B underwent relatively long-term stable population size despite a subsequent rapid demographic expansion, while subgroups C2 and C3 underwent a sudden expansion at c. 260 ka. FST and AMOVA detected low population-level genetic variation and high degrees of divergence between groups. The cryptic diversity and phylogeographic patterns found in S. fusiforme not only are essential to understand how environmental shifts and evolutionary processes shaped diversity and distribution of coastal seaweeds but also provide additional insights for conserving and managing seaweed resources and facilitate predictions of their responses to future climate change and habitat loss.

TLR4 Overexpression Inhibits Endothelial PAS Domain-Containing Protein 1 Expression in the Lower Respiratory Tract of Patients with Chronic COPD.

BACKGROUND/AIMS: The study was designed to explore the potential relationship of TLR4 and endothelial PAS domain-containing protein 1 (EPAS1) in vivo and vitro experiments. METHODS: Bronchoalveolar lavage fluid (BALF) samples were collected from 55 chronic obstructive pulmonary disease (COPD) patients and 25 healthy subjects. The differential cell count was performed using Wright-Giemsa staining. The expression levels of TLR4 and TLR5 were detected by RT-qPCR. The levels of methylation and mRNA expression of EPAS1 were assayed by bisulfite sequencing PCR and real-time PCR. The correlation of TLR4 and EPAS1 was also analyzed in TLR 4-overexpressing endothelial cells. RESULTS: The results showed that the number of neutrophils, lymphocytes and macrophages and expression of TLR 4 were significantly increased in lower respiratory tract of COPD patients. Moreover, decreased EPAS1 mRNA and increased EPAS1 promoter methylation were detected in COPD, which were closely associated with increased TLR4 expression. According to in vitro experiments, TLR 4 inhibited EPAS1 mRNA expression and promoted promoter methylation in endothelial cells. CONCLUSION: These findings suggest that TLR4 over-expression decreased EPAS1expression which contributes to the progress of COPD.

Phylogeographic data revealed shallow genetic structure in the kelp Saccharina japonica (Laminariales, Phaeophyta).

BACKGROUND: Population structure and genetic diversity of marine organisms in the Northwestern Pacific Ocean exhibited complex patterns. Saccharina japonica is a commercially and ecologically important kelp species widely distributed along the coast of Japan Sea. However, it is still poorly known about population genetics and phylogeographic patterns of wild S. japonica populations on a large geographic scale, which is an important contribution to breeding and conservation of this marine crop. RESULTS: We collected 612 mitochondrial COI and trnW-trnL sequences. Diversity indices suggested that S. japonica populations along the coast of Hokkaido exhibited the highest genetic diversity. Bayesian Analysis of Population Structure (BAPS) revealed four clusters in the kelp species (cluster 1: Hokkaido and South Korea; cluster 2: northwestern Hokkaido; cluster 3: Far Eastern Russia; cluster 4: China). The network inferred from concatenated data exhibited two shallow genealogies corresponding to two BAPS groups (cluster 2 and cluster 3). We did not detect gene flow between the two shallow genealogies, but populations within genealogy have asymmetric gene exchange. Bayesian skyline plots and neutrality tests suggested that S. japonica experienced postglacial expansion around 10.45 ka. CONCLUSIONS: The coast of Hokkaido might be the origin and diversification center of S. japonica. Gene exchange among S. japonica populations could be caused by anthropogenic interference and oceanographic regimes. Postglacial expansions and gene exchange apparently led to more shared haplotypes and less differentiation that in turn led to the present shallow phylogeographical patterns in S. japonica.

Phylogeographic structure and deep lineage diversification of the red alga Chondrus ocellatus Holmes in the Northwest Pacific.

A major goal of phylogeographic analysis using molecular markers is to understand the ecological and historical variables that influence genetic diversity within a species. Here, we used sequences of the mitochondrial Cox1 gene and nuclear internal transcribed spacer to reconstruct its phylogeography and demographic history of the intertidal red seaweed Chondrus ocellatus over most of its geographical range in the Northwest Pacific. We found three deeply separated lineages A, B and C, which diverged from one another in the early Pliocene-late Miocene (c. 4.5-7.7 Ma). The remarkably deep divergences, both within and between lineages, appear to have resulted from ancient isolations, accelerated by random drift and limited genetic exchange between regions. The disjunct distributions of lineages A and C along the coasts of Japan may reflect divergence during isolation in scattered refugia. The distribution of lineage B, from the South China Sea to the Korean Peninsula, appears to reflect postglacial recolonizations of coastal habitats. These three lineages do not coincide with the three documented morphological formae in C. ocellatus, suggesting that additional cryptic species may exist in this taxon. Our study illustrates the interaction of environmental variability and demographic processes in producing lineage diversification in an intertidal seaweed and highlights the importance of phylogeographic approaches for discovering cryptic marine biodiversity.

Expression of fibroblast specific protein-1 in pleural tuberculosis and its clinical biological significance.

BACKGROUND: Fibroblast specific protein-1 (S100A4) is related with many fibrotic diseases, but its role in the pathogenesis of pleural fibrosis has not been fully elucidated. Then we aim to investigate the expression and effect of fibroblast specific protein-1 (S100A4) in pleural tuberculosis and, subsequently, pleural fibrosis. METHODS: The expression of S100A4 in pleura was examined in 30 patients with pleural tuberculosis and 5 control (disease-free) patients by immunohistochemistry using the streptavidin-peroxidase (S-P) conjugated method. RESULTS: The expression of S100A4 in pleura was mainly distributed in the nucleus and cytoplasm of fibroblasts and vascular endothelial cells, and the positive rate was 90.0% (27 out of 30 patients with pleural tuberculosis). There were no expressions of S100A4 in the control group. In the pleura of all 30 patients with pleural tuberculosis, S100A4 had a higher expression in the two- to eight-week duration of the disease. CONCLUSIONS: S100A4 plays an important role in the phenotypic transformation of pleural mesothelial cells and the development of pleural fibrosis.

Antibacterial activity and mechanism of action of Monarda punctata essential oil and its main components against common bacterial pathogens in respiratory tract.

The aim of the current research work was to study the chemical composition of the essential oil of Monarda punctata along with evaluating the essential oil and its major components for their antibacterial effects against some frequently encountered respiratory infection causing pathogens. Gas chromatographic mass spectrometric analysis revealed the presence of 13 chemical constituents with thymol (75.2%), p-cymene (6.7%), limonene (5.4), and carvacrol (3.5%) as the major constituents. The oil composition was dominated by the oxygenated monoterpenes. Antibacterial activity of the essential oil and its major constituents (thymol, p-cymene, limonene) was evaluated against Streptococcus pyogenes, methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pneumoniae, Haemophilus influenzae and Escherichia coli. The study revealed that the essential oil and its constituents exhibited a broad spectrum and variable degree of antibacterial activity against different strains. Among the tested strains, Streptococcus pyogenes, Escherichia coli and Streptococcus pneumoniae were the most susceptible bacterial strain showing lowest MIC and MBC values. Methicillin-resistant Staphylococcus aureus was the most resistant bacterial strain to the essential oil treatment showing relatively higher MIC and MBC values. Scanning electron microscopy revealed that the essential oil induced potent and dose-dependent membrane damage in S. pyogenes and MRSA bacterial strains. The reactive oxygen species generated by the Monarda punctata essential oil were identified using 2', 7'-dichlorofluorescein diacetate (DCFDA).This study indicated that the Monarda punctata essential oil to a great extent and thymol to a lower extent triggered a substantial increase in the ROS levels in S. pyogenes bacterial cultures which ultimately cause membrane damage as revealed by SEM results.

[Correlations of S100A4 and MMP9 expressions to infiltration, metastasis and prognosis of non-small cell lung cancer].

OBJECTIVE: To observe the expressions of metastasis-associated protein (S100A4) and matrix metalloproteinase 9 (MMP9) in human non-small cell lung cancer (NSCLC) and investigate their correlations to the infiltration, metastasis and prognosis of NSCLC. METHODS: The expressions of S100A4 and MMP9 were detected in 41 NSCLC specimens and 6 normal lung tissue specimens using immunohistochemistry with SP method. Univariate and multivariate survival analysis were used to analyze the correlations of S100A4 and MMP9 to the clinicopathological characteristics and progrnosis of NSCLC. RESULTS: Compared with normal lung tissues, NSCLC showed significantly increased positivity for S100A4 and MMP9 expression (P<0.05); their expression were significantly higher in adenocarcinoma than in squamous cell carcinoma (P<0.01), and higher in metastatic NSCLC than in that without lymphatic metastasis (P<0.01). The positive expression rates of S100A4 and MMP9 were significantly higher in tumors in TNM stages III +IV than in stages II+I (P<0.05). S100A4 expression was positively correlated to tumor size (P<0.001), while MMP9 was inversely correlated to tumor differentiation (P<0.05). The expressions of S100A4 and MMP9 were both correlated to lymphatic metastasis, TNM stages and pathological types (P<0.05), and they also showed a mutual correlation (P<0.01). Univariate survival analysis confirmed the effects of histological types, lymphatic metastasis, clinical TNM stages and expressions of S100A4 and MMP9 on the survival time of NSCLC patients (P<0.001). Multivariate survival analysis identified clinical TNM stages and expressions of S100A4 and MMP9 as the independent factors affecting the prognosis of NSCLC (P<0.05). CONCLUSION: The expressions of S100A4 and MMP9 are up-regulated in NSCLC and have significant correlations to the clinical and biological behaviors of NSCLC. S100A4 and MMP9 status are independent prognostic predictors of NSCLC, and detection of their expressions may help evaluate the prognosis of NSCLC.

[Correlations of S100A4 protein expression to invasion and metastasis of non-small cell lung cancer].

BACKGROUND & OBJECTIVE: Metastasis-associated protein S100A4 is overexpressed in many malignant tumor cells; it may play a pivotal role in invasion and metastasis of malignant tumors. This study was to determine the expression of S100A4 in human non-small cell lung cancer (NSCLC), and to investigate its correlations to invasion and metastasis of NSCLC. METHODS: The expression of S100A4 in 41 specimens of NSCLC and 6 specimens of normal lung tissues was detected by SP immunohistochemistry. The correlations of S100A4 to clinicopathologic features of NSCLC were analyzed. RESULTS: The positive rate of S100A4 was significantly higher in NSCLC than in normal lung tissues (70.7% vs. 16.7%, P<0.05), and was significantly higher in adenocarcinoma than in squamous cell carcinoma (90.0% vs. 52.4%, P<0.01). The positive rate of S100A4 was significantly higher in stage III-IV than in stage II and stage I NSCLC (100.0% vs. 66.7% and 30.0%, P<0.01), while there was no obvious difference between the latter 2 groups (P>0.05). The positive rate of S100A4 was significantly higher in NSCLC with lymphatic metastasis than in NSCLC without lymphatic metastasis (90.0% vs. 52.4%, P<0.01), and significantly higher in NSCLC with tumor size of > or = 3 cm than in NSCLC with tumor size of < 3 cm (91.3% vs. 44.4%, P<0.001). The expression of S100A4 was closely related to lymphatic metastasis (r=0.480, P=0.001), and tumor size (r=0.288, P=0.017). No significant correlation was found between the expression of S100A4 and pathologic grade of NSCLC (P>0.05). CONCLUSION: S100A4 expression is up-regulated in NSCLC, and closely related to lymphatic metastasis, TNM stage and tumor size, which suggest an important role of S100A4 in the invasion and metastasis of NSCLC.