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[Over one hundred year sedimentary record of polycyclic aromatic hydrocarbons in the Andaman Sea, Malaysia]

Wu YL, Wang XH, Li YY, Hong HS, Li HY, Yin MD

Huan Jing Ke Xue, 2009 Sep 15;30(9):2512-9.
PMID: 19927796

Polycyclic aromatic hydrocarbons (PAHs) in a sediment core collected from Langkawi Island of the Andaman Sea, Malaysia were determined by GC/MS, the vertical variations of concentration and distributions of PAHs were investigated. In combining with 210Pb-dating, the PAHs sedimentary record in the last 100 years was reconstructed and their possible sources were also discussed. The sigmaPAH concentration ranged from 13.2-60.1 ng x g(-1) in the whole sedimentary section (0-56 cm) with the dominant compounds of phenanthrene, naphthalene and perylene. The sediments contaminated to a lesser extent comparing with the surrounding waters. Before the 1920s, the concentrations of PAHs were considered to be the background level, which was implied from the natural inputs. The historical records of PAHs in the core showed that two distinct peaks which represented the input time of 1960s and 1980s, respectively, inferred that there were some relatively dramatically land-based inputs, and human activities leaded a clear impact to these waters during these periods. Furthermore, PAHs diagnostic ratios indicated that PAHs in the core sediments were mainly of pyrolytic origin (combustion), accompanied with minor petroleum origin. These were related with agriculture, industry, ocean import and export, and shipping activities in the surrounding regions. Meanwhile as the vital communication line, the marine transportation of the Strait of Malacca had influenced the environmental quality of the Andaman Sea. Meanwhile, based on the sedimentary record, PAHs concentrations were found to correlate positively with humanism activities and socioeconomic development (Gross Domestic Production) in the surrounding regions.
Size Preferences Uptake of Glycosilica Nanoparticles to MDA-MB-231 Cell

Li HY, Lin HC, Huang BJ, Kai Lo AZ, Saidin S, Lai CH

Langmuir, 2020 09 29;36(38):11374-11382.
PMID: 32902993 DOI: 10.1021/acs.langmuir.0c02297

Recently, studies on the development and investigation of carbohydrate-functionalized silica nanoparticles (NPs) and their biomedicine applications such as cell-specific targeting and bioimaging has been carried out extensively. Since the number of breast cancer patients has been growing in recent years, potential NPs were being studied in this project for targeting breast cancer cells. Mannose receptors can be found on the surface of MDA-MB-231, which is a kind of human breast cancer cell line. Therefore, we decorated a cyanine 3 fluorescent dye (Cy3) and mannosides on the surface of silica NPs for the purpose of imaging and targeting. Galactoside was also introduced onto the surface of silica NPs acting as a control sample. Various sizes of silica NPs were synthesized by using different amounts of ammonium to investigate the effect of the size of NPs on the cellular uptake rate. The physical properties of these NPs were characterized by scanning electron microscope, dynamic light scattering, and their zeta potential. Cellular experiments demonstrated that mannoside-modified NPs can be uptaken by MDA-MB-231. From the experiment, we found out that the best cellular uptake rate of nanoparticle size is about 250 nm. The MTT assay showed that Man@Cy3SiO2NPs are not cytotoxic, indicating they may have the potential for biomedical applications.
Fulltext Implication of single year seasonal sampling to genetic diversity fluctuation that coordinates with oceanographic dynamics in torpedo scads near Taiwan

Su YC, Su SH, Li HY, Wang HY, Lee SC

Sci Rep, 2020 10 08;10(1):16829.
PMID: 33033371 DOI: 10.1038/s41598-020-74025-9

Many fisheries management and conservation plans are based on the genetic structure of organisms in pelagic ecosystems; however, these structures tend to vary over time, particularly in cyclic ocean currents. We performed genetic analyses on the populations of the pelagic fish, Megalaspis cordyla (Osteichthyes: Carangidae) in the area surrounding Taiwan during 2000-2001. Genotyping was performed on M. cordyla collected seasonally around Taiwan as well as specimens collected from Singapore (Malacca strait) and Indonesia (Banda Sea). Gonadosomatic indices (GSI) revealed that M. cordyla does not spawn near Taiwan. Data related to the mitochondrial control region revealed that the samples from Singapore and Indonesia represented two distinct genetic cohorts. Genotyping revealed that during the summer (June-August 2000), the Indonesian variant was dominant in eastern Taiwan (presumably following the Kuroshio Current) and in the Penghu region (following the Kuroshio Branch Current). During the same period, the Singapore genotype was dominant along the western coast of Taiwan (presumably following the South China Sea Current); however, the number dropped during the winter (December-February 2001) under the effects of the China Coast Current. Divergence time estimates indicate that the two genetic cohorts split during the last glacial maximum. Despite the fact that these results are based on sampling from a single year, they demonstrate the importance of seasonal sampling in unravelling the genetic diversity in pelagic ecosystems.
Fulltext Zyxin regulates embryonic stem cell fate by modulating mechanical and biochemical signaling interface

Zhang S, Chong LH, Woon JYX, Chua TX, Cheruba E, Yip AK, et al.

Commun Biol, 2023 Jan 18;6(1):62.
PMID: 36653484 DOI: 10.1038/s42003-023-04421-0

Biochemical signaling and mechano-transduction are both critical in regulating stem cell fate. How crosstalk between mechanical and biochemical cues influences embryonic development, however, is not extensively investigated. Using a comparative study of focal adhesion constituents between mouse embryonic stem cell (mESC) and their differentiated counterparts, we find while zyxin is lowly expressed in mESCs, its levels increase dramatically during early differentiation. Interestingly, overexpression of zyxin in mESCs suppresses Oct4 and Nanog. Using an integrative biochemical and biophysical approach, we demonstrate involvement of zyxin in regulating pluripotency through actin stress fibres and focal adhesions which are known to modulate cellular traction stress and facilitate substrate rigidity-sensing. YAP signaling is identified as an important biochemical effector of zyxin-induced mechanotransduction. These results provide insights into the role of zyxin in the integration of mechanical and biochemical cues for the regulation of embryonic stem cell fate.
Fulltext Predictors for Successful Endovascular Intervention in Chronic Carotid Artery Total Occlusion

Chen YH, Leong WS, Lin MS, Huang CC, Hung CS, Li HY, et al.

JACC Cardiovasc Interv, 2016 09 12;9(17):1825-32.
PMID: 27609258 DOI: 10.1016/j.jcin.2016.06.015

OBJECTIVES: This study sought to determine predictors for successful endovascular treatment in patients with chronic carotid artery occlusion (CAO).
BACKGROUND: Endovascular recanalization in patients with chronic CAO has been reported to be feasible, but technically challenging.
METHODS: Endovascular attempts in 138 consecutive chronic CAO patients with impaired ipsilateral hemisphere perfusion were reviewed. We analyzed potential variables including epidemiology, symptomatology, angiographic morphology, and interventional techniques in relation to the technical success.
RESULTS: The technical success rate was 61.6%. Multivariate analysis showed absence of prior neurologic event (odds ratio [OR]: 0.27; 95% confidence interval [CI]: 0.10 to 0.76), nontapered stump (OR: 0.18; 95% CI: 0.05 to 0.67), distal internal carotid artery (ICA) reconstitution via contralateral injection (OR: 0.19; 95% CI: 0.05 to 0.75), and distal ICA reconstitution at communicating or ophthalmic segments (OR:0.12; 95% CI: 0.04 to 0.36) to be independent factors associated with lower technical success. Point scores were assigned proportional to model coefficients, and technical success rates were >80% and <40% in patients with scores of ≤1 and ≥4, respectively. The c-indexes for this score system in predicting technical success was 0.820 (95% CI: 0.748 to 0.892; p < 0.001) with a sensitivity of 84.7% and a specificity of 67.9%.
CONCLUSIONS: Absence of prior neurologic event, nontapered stump, distal ICA reconstitution via contralateral injection, and distal ICA reconstitution at communicating or ophthalmic segments were identified as independent negative predictors for technical success in endovascular recanalization for CAO.