Publications by authors named "Ji Tan"

37 Publications

Pharmacological Properties of 2,4,6-Trihydroxy-3-Geranyl Acetophenone and the Underlying Signaling Pathways: Progress and Prospects.

Front Pharmacol 2021 31;12:736339. Epub 2021 Aug 31.

Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang, Malaysia.

2,4,6-Trihydroxy-3-geranyl acetophenone (tHGA) is a bioactive phloroglucinol compound found in (Champ. ex Benth.) T.G.Hartley, a medicinal plant vernacularly known as "tenggek burung". A variety of phytochemicals have been isolated from different parts of the plant including leaves, stems, and roots by using several extraction methods. Specifically, tHGA, a drug-like compound containing phloroglucinol structural core with acyl and geranyl group, has been identified in the methanolic extract of the young leaves. Due to its high nutritional and medicinal values, tHGA has been extensively studied by using various experimental models. These studies have successfully discovered various interesting pharmacological activities of tHGA such as anti-inflammatory, endothelial and epithelial barrier protective, anti-asthmatic, anti-allergic, and anti-cancer. More in-depth investigations later found that these activities were attributable to the modulatory actions exerted by tHGA on specific molecular targets. Despite these findings, the association between the mechanisms and signaling pathways underlying each pharmacological activity remains largely unknown. Also, little is known about the medicinal potentials of tHGA as a drug lead in the current pharmaceutical industry. Therefore, this mini review aims to summarize and relate the pharmacological activities of tHGA in terms of their respective mechanisms of action and signaling pathways in order to present a perspective into the overall modulatory actions exerted by tHGA. Besides that, this mini review will also pinpoint the unexplored potentials of this compound and provide some valuable insights into the potential applications of tHGA which may serve as a guide for the development of modern medication in the future.
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http://dx.doi.org/10.3389/fphar.2021.736339DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8438195PMC
August 2021

A Novel Stimuli-Responsive Injectable Antibacterial Hydrogel to Achieve Synergetic Photothermal/Gene-Targeted Therapy towards Uveal Melanoma.

Adv Sci (Weinh) 2021 Jul 31:e2004721. Epub 2021 Jul 31.

Department of Ophthalmology, Ninth People's Hospital, Shanghai JiaoTong University School of Medicine, Shanghai, 200025, P. R. China.

Uveal melanoma (UM) is the most prevalent primary intraocular malignant tumor with a high lethal rate. Patients who undergo conventional enucleation treatments consistently suffer permanent blindness, facial defects, and mental disorders, therefore, novel therapeutic modalities are urgently required. Herein, an injectable and stimuli-responsive drug delivery antibacterial hydrogel ([email protected]@DC_AC50) is constructed via a facile grinding method that is inspired by the preparation process of traditional Chinese medicine. The incorporation of gold nanorods can enhance the mechanical strength of the hydrogel and realize photothermal therapy (PTT) and thermosensitive gel-sol transformation to release the gene-targeted drug DC_AC50 on demand in response to low-density near-infrared (NIR) light. The orthotopic model of UM is built successfully and indicates the excellent efficiency of [email protected]@DC_AC50 in killing tumors without damage to normal tissue because of its synergistic mild temperature PTT and gene-targeted therapy. Moreover, the eyeball infection model reveals the remarkable antibacterial properties of the hydrogel which can prevent endophthalmitis in the eyeball. There is negligible difference between the [email protected]@DC_AC50+NIR group and normal group. This NIR light-triggered gene-targeted therapy/PTT/antibacterial treatment pattern provides a promising strategy for building multifunctional therapeutic platform against intraocular tumors and exhibits great potential for the clinical treatment of UM.
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http://dx.doi.org/10.1002/advs.202004721DOI Listing
July 2021

Compensating nonlinear temperature dependence of ultrasonic motor.

Ultrasonics 2021 Dec 14;117:106522. Epub 2021 Jul 14.

Center of Ultra-precision Optoelectronic Instrument Engineering, Harbin Institute of Technology, Harbin 150080, China; Key Lab of Ultra-precision Intelligent Instrumentation (Harbin Institute of Technology), Ministry of Industry and Information Technology, Harbin 150080, China.

This article aims at realizing the linear parameter-varying (LPV) controller synthesis to compensate temperature dependence for the ultrasonic motor (USM). Initially, based on the improved optimal frequency tracking scheme, the compact LPV model is investigated to approximate the nonlinear temperature dependence. With the aid of the simulation tool, the accuracy of the proposed LPV model is proven. The LPV controller can be an appropriate choice to ensure the stability of passive nonlinear system. In view of the very strictly passivity (VSP) theorem, the VSP LPV controller is constructed as negative feedback. A set of well-designed experimental setup employed the Shinsei USR60 type USM is built afterwards, and the controller implemented by the host is applied to verify the control effect. Compared with the non-model-based controller, the USM with the proposed controller displays better performance, such as more stable output rotational speed. The feasible model in this paper is of great significance to USM. Particularly, the proposed modeling and control methodology are beneficial to the existing optimum frequency tracking technology for the USM.
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http://dx.doi.org/10.1016/j.ultras.2021.106522DOI Listing
December 2021

Biomedical Implants with Charge-Transfer Monitoring and Regulating Abilities.

Adv Sci (Weinh) 2021 08 24;8(16):e2004393. Epub 2021 Jun 24.

State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institutes of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China.

Transmembrane charge (ion/electron) transfer is essential for maintaining cellular homeostasis and is involved in many biological processes, from protein synthesis to embryonic development in organisms. Designing implant devices that can detect or regulate cellular transmembrane charge transfer is expected to sense and modulate the behaviors of host cells and tissues. Thus, charge transfer can be regarded as a bridge connecting living systems and human-made implantable devices. This review describes the mode and mechanism of charge transfer between organisms and nonliving materials, and summarizes the strategies to endow implants with charge-transfer regulating or monitoring abilities. Furthermore, three major charge-transfer controlling systems, including wired, self-activated, and stimuli-responsive biomedical implants, as well as the design principles and pivotal materials are systematically elaborated. The clinical challenges and the prospects for future development of these implant devices are also discussed.
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http://dx.doi.org/10.1002/advs.202004393DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8373130PMC
August 2021

Cryptic species and grey zone speciation of the Barbodes binotatus complex (Teleostei, Cyprinidae) in Sundaland.

J Fish Biol 2021 Jun 22. Epub 2021 Jun 22.

Department of Agricultural and Food Sciences, Faculty of Science, Universiti Tunku Abdul Rahman, Kampar, Malaysia.

Morphology-based taxonomy of freshwater fish is effective when there are representative specimens covering large regions. However, in Sundaland, where the presence of cryptic species is high, the technique has its limitations. This is compounded by uncritical descriptions of holotypes in old literature. We demonstrate the problem using Barbodes binotatus first described from an ink drawing. Several species in the Barbodes genus of Sundaland exhibit morphological similarity to B. binotatus. We applied new DNA sequences of 16S, cytochrome c oxidase subunit I (COI), cytochrome b (Cytb) and recombination-activating gene 1 (RAG1), and pigmentation markers to clarify species complex boundaries in the Malay Peninsula, namely B. aff. binotatus "Malay Peninsula", Barbodes cf. banksi and Barbodes rhombeus. Results suggest B. binotatus-like specimens in the Malay Peninsula are B. rhombeus based on a threshold of 3% COI genetic divergence. B. aff. binotatus recorded in Sumatra, Borneo and the Philippines are likely valid but undescribed species. However, if the 2% COI threshold is applied, some populations in the northern Malay Peninsula would qualify as new and undescribed species. The implications of the 2% threshold and the likelihood of "grey zone" incipient populations are discussed. We further found a rapid visual method, not reported previously, to delineate B. aff. binotatus and B. cf. banksi, but it requires further validation. Additionally, we offer fresh perspectives by discussing the roles of biological species concept, morphological species concept, genetic species concept and mate recognition concept in the B. binotatus complex. Our findings reinforce the standpoint that species delineation is not entirely a binary process, but there is a spectrum to consider, especially in biogeography intersection regions.
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http://dx.doi.org/10.1111/jfb.14829DOI Listing
June 2021

Complete mitochondrial genomes and phylogenetic relationships of the genera Nephila and Trichonephila (Araneae, Araneoidea).

Sci Rep 2021 May 21;11(1):10680. Epub 2021 May 21.

Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603, Kuala Lumpur, Malaysia.

Spiders of the genera Nephila and Trichonephila are large orb-weaving spiders. In view of the lack of study on the mitogenome of these genera, and the conflicting systematic status, we sequenced (by next generation sequencing) and annotated the complete mitogenomes of N. pilipes, T. antipodiana and T. vitiana (previously N. vitiana) to determine their features and phylogenetic relationship. Most of the tRNAs have aberrant clover-leaf secondary structure. Based on 13 protein-coding genes (PCGs) and 15 mitochondrial genes (13 PCGs and two rRNA genes), Nephila and Trichonephila form a clade distinctly separated from the other araneid subfamilies/genera. T. antipodiana forms a lineage with T. vitiana in the subclade containing also T. clavata, while N. pilipes forms a sister clade to Trichonephila. The taxon vitiana is therefore a member of the genus Trichonephila and not Nephila as currently recognized. Studies on the mitogenomes of other Nephila and Trichonephila species and related taxa are needed to provide a potentially more robust phylogeny and systematics.
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http://dx.doi.org/10.1038/s41598-021-90162-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8139964PMC
May 2021

Strontium ranelate incorporated 3D porous sulfonated PEEK simulating MC3T3-E1 cell differentiation.

Regen Biomater 2021 Feb 28;8(1):rbaa043. Epub 2020 Nov 28.

Department of Pharmacy, Tongren Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200336, China.

Polyetheretherketone (PEEK) has been used as an implant material because it has similar mechanical properties to natural bone. However, inferior osseointegration and bioinertness hamper the clinical application of PEEK. In this study, the surfaces of sulfonated three-dimensional (3D) PEEK porous structures were loaded with different concentrations of strontium ranelate, a compound commonly used in the treatment or prevention of osteoporosis by promoting bone formation and inhibiting bone resorption. Field-emission scanning electron microscopy was used to characterize the topography of the structures, elemental carbon, oxygen and strontium contents were measured by X-ray photoelectron spectroscopy, and surface zeta potentials and water-contact angle were also measured. The results indicated that strontium ranelate was successfully loaded onto the 3D porous structures. cellular results showed that strontium ranelate-treated sulfonated PEEK (SP-SR) strengthened the adhesion of MC3T3-E1 cells. The activity of alkaline phosphatase, collagen secretion and extracellular matrix mineralization deposition of MC3T3-E1 cells were also improved on the surface of SP-SR. These results indicate that SP-SR could serve a new implant candidate for surgical treatment.
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http://dx.doi.org/10.1093/rb/rbaa043DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7947580PMC
February 2021

The Potential use of Honey as a Remedy for Allergic Diseases: A Mini Review.

Front Pharmacol 2020 26;11:599080. Epub 2021 Jan 26.

Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Selangor, Malaysia.

Honey has been conventionally consumed as food. However, its therapeutic properties have also gained much attention due to its application as a traditional medicine. Therapeutic properties of honey such as anti-microbial, anti-inflammatory, anti-cancer and wound healing have been widely reported. A number of interesting studies have reported the potential use of honey in the management of allergic diseases. Allergic diseases including anaphylaxis, asthma and atopic dermatitis (AD) are threatening around 20% of the world population. Although allergic reactions are somehow controllable with different drugs such as antihistamines, corticosteroids and mast cell stabilizers, modern dietary changes linked with allergic diseases have prompted studies to assess the preventive and therapeutic merits of dietary nutrients including honey. Many scientific evidences have shown that honey is able to relieve the pathological status and regulate the recruitment of inflammatory cells in cellular and animal models of allergic diseases. Clinically, a few studies demonstrated alleviation of allergic symptoms in patients after application or consumption of honey. Therefore, the objective of this mini review is to discuss the effectiveness of honey as a treatment or preventive approach for various allergic diseases. This mini review will provide insights into the potential use of honey in the management of allergic diseases in clinical settings.
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http://dx.doi.org/10.3389/fphar.2020.599080DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7870997PMC
January 2021

Metallo-Helicoid with Double Rims: Polymerization Followed by Folding by Intramolecular Coordination.

Angew Chem Int Ed Engl 2021 01 18;60(3):1281-1289. Epub 2020 Nov 18.

College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, Guangdong, 518055, China.

In this study, we established a feasible strategy to construct a new type of metallo-polymer with helicoidal structure through the combination of covalent polymerization and intramolecular coordination-driven self-assembly. In the design, a tetratopic monomer (M) was prepared with two terminal alkynes in the outer rim for polymerization, and two terpyridines (TPYs) in the inner rim for subsequent folding by selective intramolecular coordination. Then, the linear covalent polymer (P) was synthesized by polymerization of M via Glaser-Hay homocoupling reaction. Finally, intramolecular coordination interactions between TPYs and Zn(II) folded the backbone of P into a right- or left-handed metallo-helicoid (H) with double rims. Owing to multiple positive charges on the inner rim of helicoid, double-stranded DNA molecules (dsDNA) could interact with H through electrostatic interactions. Remarkably, dsDNA allowed exclusive formation of H with right handedness by means of chiral induction.
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http://dx.doi.org/10.1002/anie.202010696DOI Listing
January 2021

Enhanced physicochemical and biological properties of C/Cu dual ions implanted medical titanium.

Bioact Mater 2020 Jun 19;5(2):377-386. Epub 2020 Mar 19.

State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050, China.

It is increasingly popular for titanium and its alloys to be utilized as the medical implants. However, their bio-inert nature and lack of antibacterial ability limit their applications. In this work, by utilizing plasma immersion ion implantation and deposition (PIII&D) technology, the titanium surface was modified by C/Cu co-implantation. The mechanical property, corrosion resistance, antibacterial ability and cytocompatibility of modified samples were studied. Results indicate that after C/Cu co-implantation, copper nanoparticles were observed on the surface of titanium, and titanium carbide existed on the near surface region of titanium. The modified surface displayed good mechanical property and corrosion resistance. The Cu/C galvanic corrosion existed on the titanium surface implanted by C/Cu dual ions, and release of copper ions can be effectively controlled by the galvanic corrosion effect. Moreover, improved antibacterial performance of titanium surface can be achieved without cytotoxicity.
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http://dx.doi.org/10.1016/j.bioactmat.2020.02.017DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7083793PMC
June 2020

A facile and universal strategy to endow implant materials with antibacterial ability via alkalinity disturbing bacterial respiration.

Biomater Sci 2020 Mar;8(7):1815-1829

State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 200050, China.

Multifarious strategies have been proposed to enhance the antibacterial ability of implant surfaces for preventing bacterial infection, however, developing facile and universal modification methods still remains extremely elusive. Herein, inspired by the fact that the electron transfer respiratory chain of bacteria is embedded in the membrane, we proposed a novel strategy of local alkalinity disturbing bacterial respiration to endow implant materials with antibacterial ability. As a demonstration, MgO was deposited on biomedical titanium via magnetron sputtering to regulate surface alkalinity. With the thickness of MgO films increasing, they exhibited an excellent antibacterial rate against both Gram-negative and positive bacteria. The antibacterial mechanism confirmed that the alkaline surface can disturb the bacterial respiration action via weakening the transmembrane proton concentration gradient, resulting in the blockage of energy metabolism and the increase of oxidative stress of bacteria. Cell experiments indicated that MgO films not only have no obvious cytotoxicity to osteoblast cells, but can also selectively kill bacteria and promote cell proliferation in the presence of both bacteria and cells. More importantly, the by-product of MgO was only the biocompatible Mg2+, reducing any concerns about potential toxic effects. Furthermore, sputtering alkaline MgO films was confirmed to work well on polyetheretherketone polymer and zirconia ceramic implants, which indicates that this strategy has broad prospects of clinical application for preventing implant-associated bacterial infection.
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http://dx.doi.org/10.1039/c9bm01793cDOI Listing
March 2020

The Ability of Baseline Triglycerides and Total Cholesterol Concentrations to Predict Incidence of Type 2 Diabetes Mellitus in Chinese Men and Women: A Longitudinal Study in Qingdao, China.

Biomed Environ Sci 2019 Dec;32(12):905-913

Qingdao Municipal Center for Disease Control and Prevention, Qingdao Institute of Preventive Medicine, Qingdao 266033, Shandong, China.

Objective: The purpose of this study was to assess the association between triglycerides (TG), total cholesterol (TC) at baseline, and type 2 diabetes mellitus (T2DM) incidence in a general Chinese population. Further, it aimed to evaluate the ability of TG and TC to predict T2DM incidence.

Methods: Qingdao Diabetes Prevention Program participants recruited between 2006 and 2009 were followed up in 2012-2015. TG, TC, and T2DM status were measured. Cox proportional hazards models were used to estimate the association between TG, TC, and T2DM incidence. The receiver operating characteristic (ROC) curve was used to evaluate the ability of TG and TC to identify T2DM participants.

Results: The incidence of T2DM significantly increased with TG in women and TC in both men and women (Ptrend < 0.05). Univariate Cox regression indicated that higher TG {borderline high TG [hazards ratio (HR): 2.05; 95% confidence interval (CI): 1.40, 3.00] and hypertriglyceridemia [HR: 2.64; 95% CI: 1.68, 4.15]} and TC [hypercholesterolemia (HR: 2.05; 95% CI: 1.43, 2.95)] were significantly associated with increased risk of T2DM incidence in women but not in men. Multivariate Cox regression showed that hypertriglyceridemia in women (HR: 1.78, 95% CI: 1.07, 2.97), borderline high TC in men (HR: 1.61, 95% CI: 1.04, 2.48), and hypercholesterolemia in women (HR: 1.68, 95% CI: 1.81, 2.61) had a higher significant risk of T2DM incidence. The optimal cutoff values of TG were > 1.15 and > 1.23 mmol/L in men and women, respectively. For TC, they were > 5.17 and > 5.77 mmol/L in men and women, respectively. The area under the ROCs of TG and TC were 0.54 (0.51-0.57) and 0.55 (0.52-0.58), respectively, in men, and 0.60 (0.58-0.62) and 0.59 (0.56-0.61), respectively, in women.

Conclusion: Elevated TG and TC were risk factors for T2DM incidence. However, no predictive capacity was found for both factors to identify T2DM incidence in Chinese men and women. Hence, TG and TC levels in both Chinese men and women might be used for decreasing the incidence of T2DM but no clinical predictive capacity for T2DM.
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http://dx.doi.org/10.3967/bes2019.113DOI Listing
December 2019

[Effect of Increasing Tidewater Inundation on Porewater Geochemistries and CO and CH Effluxes in the Tidal Freshwater Marshes of the Minjiang River Estuary, Southeast China].

Huan Jing Ke Xue 2019 Dec;40(12):5493-5502

Institute of Geography, Fujian Normal University, Fuzhou 350007, China.

While the effect of increasing tidewater inundation caused by sea-level rise on carbon cycling had been well studied in saltmarshes, little is known about the effect of increasing tidewater inundation on CO and CH effluxes in the tidal freshwater marsh soils. Herein, the effects of tide inundation on porewater geochemistries (NH, NO, DOC, dissolved CH, and DIC) and CH and CO effluxes were examined in the soils of tidal freshwater marshes in the Minjiang River Estuary, East China Sea. By applying "mesocosm" and a simulated tide pool, the tide inundation height increased by 15 cm and 30 cm over the control (CK). The CO effluxes decreased by 28.53% and 36.56%, and the dissolved CH concentrations increased by 47.83% and 73.91%, in treatments (CK+15 cm) and (CK+30 cm), respectively. The CH effluxes did not change significantly in the treatment (CK+15 cm), but increased by 29.27% in treatment (CK+30 cm). The increasing tidewater inundation had no significant impact on DOC concentrations, but increased NH concentrations and decreased DIC and NO concentrations. Increasing tide inundation also reduced the temperature sensitivity of CH and CO effluxes. The study highlighted that the sea level rise-induced increase in tidewater inundation would decrease the annual global warming potential of tidal freshwater wetlands by 28% and 35% in the next 50 and 100 years, respectively.
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http://dx.doi.org/10.13227/j.hjkx.201905214DOI Listing
December 2019

Diversiform and Transformable Glyco-Nanostructures Constructed from Amphiphilic Supramolecular Metallocarbohydrates through Hierarchical Self-Assembly: The Balance between Metallacycles and Saccharides.

ACS Nano 2019 11 31;13(11):13474-13485. Epub 2019 Oct 31.

The State Key Laboratory of Molecular Engineering of Polymers and Department of Macromolecular Science , Fudan University , Shanghai 200433 , PR China.

During the past decade, self-assembly of saccharide-containing amphiphilic molecules toward bioinspired functional glycomaterials has attracted continuous attention due to their various applications in fundamental and practical areas. However, it still remains a great challenge to prepare hierarchical glycoassemblies with controllable and diversiform structures because of the complexity of saccharide structures and carbohydrate-carbohydrate interactions. Herein, through hierarchical self-assembly of modulated amphiphilic supramolecular metallocarbohydrates, we successfully prepared various well-defined glyco-nanostructures in aqueous solution, including vesicles, solid spheres, and opened vesicles depending on the molecular structures of metallocarbohydrates. More attractively, these glyco-nanostructures can further transform into other morphological structures in aqueous solutions such as worm-like micelles, tubules, and even tupanvirus-like vesicles (TVVs). It is worth mentioning that distinctive anisotropic structures including the opened vesicles (OVs) and TVVs were rarely reported in glycobased nano-objects. This intriguing diversity was mainly controlled by the subtle structural trade-off of the two major components of the amphiphiles, , the saccharides and metallacycles. To further understand this precise structural control, molecular simulations provided deep physical insights on the morphology evolution and balancing of the contributions from saccharides and metallacycles. Moreover, the multivalency of glyco-nanostructures with different shapes and sizes was demonstrated by agglutination with a diversity of sugar-binding protein receptors such as the plant lectins Concanavalin A (ConA). This modular synthesis strategy provides access to systematic tuning of molecular structure and self-assembled architecture, which undoubtedly will broaden our horizons on the controllable fabrication of biomimetic glycomaterials such as biological membranes and supramolecular lectin inhibitors.
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http://dx.doi.org/10.1021/acsnano.9b07134DOI Listing
November 2019

Effects of Tidal Scenarios on the Methane Emission Dynamics in the Subtropical Tidal Marshes of the Min River Estuary in Southeast China.

Int J Environ Res Public Health 2019 08 5;16(15). Epub 2019 Aug 5.

Institute of Geography, Fujian Normal University, Fuzhou 350007, China.

In order to accurately estimate the effects of tidal scenarios on the CH emission from tidal wetlands, we examined the CH effluxes, dissolved CH concentrations, and environmental factors (including in situ pH, Eh and electrical conductivity, porewater SO, NO, and NH) during inundation and air-exposure periods in high- and low-tide seasons in the Min River Estuary in southeast China. By applying static and floating chambers, our results showed that the CH effluxes during the inundation periods were relatively constant and generally lower than those during the air-exposed periods in both seasons. When compared, the CH effluxes during the air-exposed periods were significantly higher in the high-tide season than those in the low-tide season. In contrast, CH effluxes during the inundation periods were significantly lower in the high-tide season than those in the low-tide season. During the inundation periods, dissolved CH concentrations were inversely proportional to in situ Eh. Under air-exposed conditions, CH effluxes were proportional to in situ pH in both seasons, while the dissolved CH concentrations were negatively correlated with the porewater SO concentrations in both seasons. Our results highlighted that CH effluxes were more dynamic between inundation and air-exposure periods compared to low- and high-tide seasons.
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http://dx.doi.org/10.3390/ijerph16152790DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6695609PMC
August 2019

Mast cell stabilizing effect of a geranyl acetophenone in dengue virus infection using model of DENV3-induced RBL-2H3 cells.

Biosci Rep 2019 06 4;39(6). Epub 2019 Jun 4.

Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43400, Malaysia

Mast cells (MCs), a type of immune effector cell, have recently become recognized for their ability to cause vascular leakage during dengue virus (DENV) infection. Although MC stabilizers have been reported to attenuate DENV induced infection in animal studies, there are limited studies on the use of MC stabilizers against DENV induced MC degranulation. 2,4,6-trihydroxy-3-geranyl acetophenone (tHGA) has been reported to be a potential MC stabilizer by inhibiting IgE-mediated MC activation in both cellular and animal models. The present study aims to establish an model of DENV3-induced RBL-2H3 cells using ketotifen fumarate as a control drug, as well as to determine the effect of tHGA on the release of MC mediators upon DENV infection. Our results demonstrated that the optimal multiplicities of infection (MOI) were 0.4 × 10 and 0.8 × 10 focus forming units (FFU)/cell. Ketotifen fumarate was proven to attenuate DENV3-induced RBL-2H3 cells degranulation in this model. In contrast, tHGA was unable to attenuate the release of both β-hexosaminidase and tumor necrosis factor (TNF)-α. Nonetheless, our study has successfully established an model of DENV3-induced RBL-2H3 cells, which might be useful for the screening of potential MC stabilizers for anti-dengue therapies.
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http://dx.doi.org/10.1042/BSR20181273DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6549089PMC
June 2019

[Parallel Factor Analysis of Fluorescence Excitation Emission Matrix Spectroscopy of CDOM from the Mid-culture Period of Shrimp Ponds in a Subtropical Estuary].

Huan Jing Ke Xue 2019 Jan;40(1):164-171

School of Environment and Resource, Fuzhou University, Fuzhou 350116, China.

Components of chromophoric dissolved organic matter (CDOM) from eight coastal land-based shrimp ponds in the Minjiang, Mulan, and Jiulong rivers of subtropical southeastern China were determined by fluorescence excitation emission matrix spectroscopy combined with parallel factor analysis (EEMs-PARAFAC). Four separate fluorescence components, including two protein-like components (C1, C4) and two humic-like components (C2, C3), were identified as the dominant components of the CDOM in these shrimp ponds. The fluorescence indices (FI, BIX, and HIX) suggest that the CDOM of shrimp ponds shows low humification and is mainly derived from spontaneous sources. The protein-like and humic-like components have similar sources and exhibit a similar geochemical behavior. The salinity is negatively correlated with all CDOM fractions, whereas the DOC concentrations show only a positive correlation with the humic fractions of the CDOM. This study provides a scientific basis for the photochemical properties of CDOM in shrimp ponds.
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http://dx.doi.org/10.13227/j.hjkx.201805235DOI Listing
January 2019

Effect of Local Alkaline Microenvironment on the Behaviors of Bacteria and Osteogenic Cells.

ACS Appl Mater Interfaces 2018 Dec 27;10(49):42018-42029. Epub 2018 Nov 27.

State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics , Chinese Academy of Sciences , Shanghai 200050 , China.

The interactions between material surfaces and bacteria/cells have been widely investigated, based on which biomaterials with antibacterial and osteogenic abilities can be designed to conquer implant failures. The pH of environments is known to affect bacterial growth and bone formation/resorption, and it is possible that the antibacterial and osteogenic abilities of biomaterials can be simultaneously improved by regulating their surface alkalinity. Herein, we fabricated many kinds of films with various alkalinity levels on titanium surface to explore the effect of local alkaline microenvironments around material surfaces on the behaviors of bacteria and osteogenic cells. Both Gram-positive and -negative bacteria were cultured on sample surfaces to investigate their antibacterial effects. Cell adhesion, proliferation, and alkaline phosphatase (ALP) activities were investigated by culturing both bone mesenchymal stem cells (MSCs) and osteoblast cells on sample surfaces. The results show that an appropriate local alkaline environment can effectively inhibit the growth of both Gram-positive and -negative bacteria through inactivating ATP synthesis and inducing oxidative stress. Meanwhile, it can promote the osteogenic differentiation of bone MSCs and enhance the proliferation and ALP activities of osteoblast cells. In conclusion, material surfaces endowed with appropriate alkalinity can possess antibacterial and osteogenic properties, which provide a novel strategy to design multifunctional biomaterials for bone generation.
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http://dx.doi.org/10.1021/acsami.8b15724DOI Listing
December 2018

Argiope hoiseni, a new species of the spider genus Argiope (Araneae, Araneidae) from Peninsular Malaysia based on morphology and molecular analyses.

Authors:
Ji Tan

Zootaxa 2018 Aug 7;4457(1):129-142. Epub 2018 Aug 7.

Department of Agricultural and Food Sciences, Universiti Tunku Abdul Rahman (UTAR), 31900 Kampar, Perak, Malaysia..

A new species of Argiope Audouin 1826, A. hoiseni new species is described from Perak and Selangor, Peninsular Malaysia based on morphology and DNA information of the mitochondrial (16S rRNA, COI and COII) and nuclear-encoded (H3A, 18S rRNA) molecular markers. Epigynal structure suggested Argiope hoiseni to be similar to A. jinghongensis Yin, Peng Wang 1994, A. luzona (Walckenaer 1841), A. pulchella Thorell 1881 and A. taprobanica Thorell 1887. Molecular sequence data including the new species inferred that it is monophyletic with an intraspecific variation of 0.87-3.59 % based on the 16S+COI+COII+H3A dataset. Phylogenetic analyses also revealed insights into the evolutionary lineages of Argiope species in Southeast Asia as well as corroborated recent taxonomic changes and species synonymies associated with Argiope. Two new distribution records were also reported for A. chloreis Thorell,1877 and A. doleschalli Thorell, 1873 in Peninsular Malaysia.
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http://dx.doi.org/10.11646/zootaxa.4457.1.6DOI Listing
August 2018

Synergistic Effects of N/Cu Dual Ions Implantation on Stimulating Antibacterial Ability and Angiogenic Activity of Titanium.

ACS Biomater Sci Eng 2018 Sep 22;4(9):3185-3193. Epub 2018 Aug 22.

State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China.

Titanium and its alloys have been commonly used as implant materials. However, the inherent bioinert nature hinders its good osseointegration which limits its permanent clinical applications. In this work, nitrogen (N) and copper (Cu) dual ions were implanted into titanium by plasma immersion ion implantation and deposition (PIII&D) technology. The corrosion resistance, mechanical property, antibacterial ability, and angiogenic activity of the modified titanium surfaces were investigated. Experimental results show that titanium nitride (TiN) film embedded with Cu nanoparticles (Cu NPs) forms on the surface of the N/Cu dual ions implanted titanium. The N/Cu dual ions implanted titanium exhibits excellent corrosion resistance and mechanical property. The galvanic corrosion of Cu/TiN can effectively control copper ion release to enhance the antibacterial and angiogenic performances of the Ti surface.
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http://dx.doi.org/10.1021/acsbiomaterials.8b00501DOI Listing
September 2018

Major Bioactive Compounds in Essential Oils Extracted From the Rhizomes of : A Mini-Review on the Anti-allergic and Immunomodulatory Properties.

Front Pharmacol 2018 20;9:652. Epub 2018 Jun 20.

Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Seri Kembangan, Malaysia.

is part of the family, one of the largest families of the plant kingdom. is a perennial, aromatic and tuberose plant that grows in humid locations where its center of distribution is located in the South-East Asia region. This plant has been traditionally used in foods and beverages and for ornamental purposes. Although many studies have reported on the biomedical applications of , the anti-allergic effects of and its major bioactive compounds have not yet been summarized in detail. Many major metabolites that have been reported to contain anti-allergic properties are terpene compounds which can be found in the essential oil extracted from the rhizomes of , such as zerumbone, limonene, and humulene. The rhizome is among the part of that has been widely used for many studies due to its exceptional biomedical applications. Most of these studies have shown that the essential oil, which can be obtained through hydro-distillation of the rhizomes from , is enriched with various active metabolites. Therefore, this mini-review provides an overview of the main aspects related to the anti-allergic and immunomodulatory properties of the major bioactive compounds found in the essential oils extracted from the rhizomes of , with the aim of demonstrating the importance of essential oil extracted from the rhizomes of and its bioactive compounds in the treatment of allergy and allergy-related diseases, in addition to other widely reported and extensively studied biomedical applications.
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http://dx.doi.org/10.3389/fphar.2018.00652DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6019502PMC
June 2018

LAT is essential for the mast cell stabilising effect of tHGA in IgE-mediated mast cell activation.

Biochem Pharmacol 2017 11 13;144:132-148. Epub 2017 Aug 13.

Department of Biomedical Science, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43300, Malaysia. Electronic address:

Mast cells play a central role in the pathogenesis of allergic reaction. Activation of mast cells by antigens is strictly dependent on the influx of extracellular calcium that involves a complex interaction between signalling molecules located within the cells. We have previously reported that tHGA, an active compound originally isolated from a local shrub known as Melicope ptelefolia, prevented IgE-mediated mast cell activation and passive systemic anaphylaxis by suppressing the release of interleukin-4 (IL-4) and tumour necrosis factor (TNF)-α from activated rat basophilic leukaemia (RBL)-2H3 cells. However, the mechanism of action (MOA) as well as the molecular target underlying the mast cell stabilising effect of tHGA has not been previously investigated. In this study, DNP-IgE-sensitised RBL-2H3 cells were pre-treated with tHGA before challenged with DNP-BSA. To dissect the MOA of tHGA in IgE-mediated mast cell activation, the effect of tHGA on the transcription of IL-4 and TNF-α mRNA was determined using Real Time-Polymerase Chain Reaction (qPCR) followed by Calcium Influx Assay to confirm the involvement of calcium in the activation of mast cells. The protein lysates were analysed by using Western Blot to determine the effect of tHGA on various important signalling molecules in the LAT-PLCγ-MAPK and PI3K-NFκB pathways. In order to identify the molecular target of tHGA in IgE-mediated mast cell activation, the LAT and LAT2 genes in RBL-2H3 cells were knocked-down by using RNA interference to establish a LAT/LAT2 competition model. The results showed that tHGA inhibited the transcription of IL-4 and TNF-α as a result of the suppression of calcium influx in activated RBL-2H3 cells. The results from Western Blot revealed that tHGA primarily inhibited the LAT-PLCγ-MAPK pathway with partial inhibition on the PI3K-p65 pathway without affecting Syk. The results from RNAi further demonstrated that tHGA failed to inhibit the release of mediators associated with mast cell degranulation under the LAT/LAT2 competition model in the absence of LAT. Collectively, this study concluded that the molecular target of tHGA could be LAT and may provide a basis for the development of a mast cell stabiliser which targets LAT.
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http://dx.doi.org/10.1016/j.bcp.2017.08.010DOI Listing
November 2017

Anti-allergic activity of 2,4,6-trihydroxy-3-geranylacetophenone (tHGA) via attenuation of IgE-mediated mast cell activation and inhibition of passive systemic anaphylaxis.

Toxicol Appl Pharmacol 2017 03 4;319:47-58. Epub 2017 Feb 4.

Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43400, Malaysia. Electronic address:

tHGA, a geranyl acetophenone compound originally isolated from a local shrub called Melicope ptelefolia, has been previously reported to prevent ovalbumin-induced allergic airway inflammation in a murine model of allergic asthma by targeting cysteinyl leukotriene synthesis. Mast cells are immune effector cells involved in the pathogenesis of allergic diseases including asthma by releasing cysteinyl leukotrienes. The anti-asthmatic properties of tHGA could be attributed to its inhibitory effect on mast cell degranulation. As mast cell degranulation is an important event in allergic responses, this study aimed to investigate the anti-allergic effects of tHGA in cellular and animal models of IgE-mediated mast cell degranulation. For in vitro model of IgE-mediated mast cell degranulation, DNP-IgE-sensitized RBL-2H3 cells were pre-treated with tHGA before challenged with DNP-BSA to induce degranulation. For IgE-mediated passive systemic anaphylaxis, Sprague Dawley rats were sensitized by intraperitoneal injection of DNP-IgE before challenged with DNP-BSA. Both in vitro and in vivo models showed that tHGA significantly inhibited the release of preformed mediators (β-hexosaminidase and histamine) as well as de novo mediators (interleukin-4, tumour necrosis factor-α, prostaglandin D and leukotriene C). Pre-treatment of tHGA also prevented IgE-challenged RBL-2H3 cells and peritoneal mast cells from undergoing morphological changes associated with mast cell degranulation. These findings indicate that tHGA possesses potent anti-allergic activity via attenuation of IgE-mediated mast cell degranulation and inhibition of IgE-mediated passive systemic anaphylaxis. Thus, tHGA may have the potential to be developed as a mast cell stabilizer for the treatment of allergic diseases in the future.
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http://dx.doi.org/10.1016/j.taap.2017.02.002DOI Listing
March 2017

Progesterone augments cell susceptibility to HIV-1 and HIV-1/HSV-2 co-infections.

J Mol Endocrinol 2016 10 18;57(3):185-99. Epub 2016 Aug 18.

Lab of Molecular VirologyDivision of Emerging Transfusion Transmitted Diseases, Center for Biologics Evaluation and Research, Food and Drug Administration, Silver Spring, Maryland, USA

In human immunodeficiency virus type 1 (HIV-1)-infected women, oral or injectable progesterone containing contraceptive pills may enhance HIV-1 acquisition in vivo, and the mechanism by which this occurs is not fully understood. In developing countries, Herpes simplex virus type-2 (HSV-2) co-infection has been shown to be a risk for increase of HIV-1 acquisition and, if co-infected women use progesterone pills, infections may increase several fold. In this study, we used an in vitro cell culture system to study the effects of progesterone on HIV-1 replication and to explore the molecular mechanism of progesterone effects on infected cells. In our in vitro model, CEMss cells (lymphoblastoid cell line) were infected with either HIV-1 alone or co-infected with HSV-2. HIV-1 viral load was measured with and without sex hormone treatment. Progesterone-treated cells showed an increase in HIV-1 viral load (1411.2 pg/mL) compared with cells without progesterone treatment (993.1 pg/mL). Increased cell death was noted with HSV-2 co-infection and in progesterone-treated cells. Similar observations were noted in peripheral blood mononuclear cells (PBMC) cells derived from three female donors. Progesterone-treated cells also showed reduced antiviral efficacy. Inflammatory cytokines and associations with biomarkers of disease progression were explored. Progesterone upregulated inflammatory cytokines and chemokines conversely and downregulated anti-apoptotic Bcl-2 expression. Nuclear protein analysis by electrophoretic mobility shift assay showed the association of progesterone with progesterone response element (PRE), which may lead to downregulation of Bcl-2. These data indicate that progesterone treatment enhances HIV-1 replication in infected cells and co-infection with HSV-2 may further fuel this process.
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http://dx.doi.org/10.1530/JME-16-0138DOI Listing
October 2016

Neuroprotective Effects of Biochanin A against β-Amyloid-Induced Neurotoxicity in PC12 Cells via a Mitochondrial-Dependent Apoptosis Pathway.

Molecules 2016 Apr 25;21(5). Epub 2016 Apr 25.

Institute of Bioscience, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia.

Alzheimer's disease is considered one of the major neurodegenerative diseases and is characterized by the production of β-amyloid (Aβ) proteins and progressive loss of neurons. Biochanin A, a phytoestrogen compound found mainly in Trifolium pratense, was used in the present study as a potential alternative to estrogen replacement therapy via the investigation of its neuroprotective effects against Aβ25-35-induced toxicity, as well as of its potential mechanisms of action in PC12 cells. Exposure of these cells to the Aβ25-35 protein significantly increased cell viability loss and apoptosis. However, the effects induced by Aβ25-35 were markedly reversed in the present of biochanin A. Pretreatment with biochanin A attenuated the cytotoxic effect of the Aβ25-35 protein by decreasing viability loss, LDH release, and caspase activity in cells. Moreover, we found that expression of cytochrome c and Puma were reduced, alongside with the restoration of Bcl-2/Bax and Bcl-xL/Bax ratio in the presence of biochanin A, which led to a decrease in the apoptotic rate. These data demonstrate that mitochondria are involved in the protective effect of biochanin A against Aβ25-35 and that this drug attenuated Aβ25-35-induced PC12 cell injury and apoptosis by preventing mitochondrial dysfunction. Thus, biochanin A might raise a possibility as a potential therapeutic agent for Alzheimer's disease and other related neurodegenerative diseases.
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http://dx.doi.org/10.3390/molecules21050548DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6274559PMC
April 2016

Association Between Serum Uric Acid and Prevalence of Type 2 Diabetes Diagnosed using HbA1c Criteria Among Chinese Adults in Qingdao, China.

Biomed Environ Sci 2015 Dec;28(12):884-93

Center for Disease Control and Prevention, Qingdao 266033, Shandong, China.

Objective: To determine whether elevated serum uric acid (UA) levels are associated with type 2 diabetes diagnosed using HbA1c levels among Chinese adults.

Methods: We conducted two population-based cross-sectional studies in Qingdao in China in 2006 and 2009. A total of 6894 (39.4% men) subjects aged 35-74 years were included in the data analysis. Newly diagnosed diabetes was defined as HbA1c level of ⋝6.5%, and prediabetes was classified as HbA1c level between 5.7% and 6.4% according to the International Diabetes Federation criteria. Multivariate logistic regression was employed to assess the association between UA and prevalence of type 2 diabetes defined using Glycated hemoglobin A1c (HbA1c) levels.

Results: Subjects with prediabetes had higher UA levels than those with normal glucose tolerance, newly diagnosed diabetes, and known diabetes, with corresponding values of 325.1 (82.5) µmol/L, 310.9 (84.2) µmol/L, 291.3 (81.7) µmol/L, 305.2 (83.6) µmol/L, respectively (P<0.001 for all comparisons). Binary logistic regression analysis showed that UA was a possible predictor for the prevalence of type 2 diabetes diagnosed using HbA1c levels, and the second quartile of UA levels had a higher odds ratio (OR: 4.088; 95% CI: 2.900-5.765) for HbA1c than the other quartiles after adjusting for age, body mass index, sex, marital status, education, income, alcohol consumption, smoking, and cardiometabolic parameters.

Conclusion: Serum UA is significantly associated with type 2 diabetes diagnosed using HbA1c levels, independent of other cardiometabolic parameters.
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http://dx.doi.org/10.3967/bes2015.122DOI Listing
December 2015

Multigene Phylogeography of Bactrocera caudata (Insecta: Tephritidae): Distinct Genetic Lineages in Northern and Southern Hemispheres.

PLoS One 2015 19;10(6):e0129455. Epub 2015 Jun 19.

Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.

Bactrocera caudata is a pest of pumpkin flower. Specimens of B. caudata from the northern hemisphere (mainland Asia) and southern hemisphere (Indonesia) were analysed using the partial DNA sequences of the nuclear 28S rRNA and internal transcribed spacer region 2 (ITS-2) genes, and the mitochondrial cytochrome c oxidase subunit I (COI), cytochrome c oxidase subunit II (COII) and 16S rRNA genes. The COI, COII, 16S rDNA and concatenated COI+COII+16S and COI+COII+16S+28S+ITS-2 nucleotide sequences revealed that B. caudata from the northern hemisphere (Peninsular Malaysia, East Malaysia, Thailand) was distinctly different from the southern hemisphere (Indonesia: Java, Bali and Lombok), without common haplotype between them. Phylogenetic analysis revealed two distinct clades (northern and southern hemispheres), indicating distinct genetic lineage. The uncorrected 'p' distance for the concatenated COI+COII+16S nucleotide sequences between the taxa from the northern and southern hemispheres ('p' = 4.46-4.94%) was several folds higher than the 'p' distance for the taxa in the northern hemisphere ('p' = 0.00-0.77%) and the southern hemisphere ('p' = 0.00%). This distinct difference was also reflected by concatenated COI+COII+16S+28S+ITS-2 nucleotide sequences with an uncorrected 'p' distance of 2.34-2.69% between the taxa of northern and southern hemispheres. In accordance with the type locality the Indonesian taxa belong to the nominal species. Thus the taxa from the northern hemisphere, if they were to constitute a cryptic species of the B. caudata species complex based on molecular data, need to be formally described as a new species. The Thailand and Malaysian B. caudata populations in the northern hemisphere showed distinct genetic structure and phylogeographic pattern.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0129455PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4474862PMC
April 2016

Genetic and environmental effects on the bone development of the hand and wrist in Chinese young twins.

Biomed Environ Sci 2015 Mar;28(3):235-8

School of Public Health, Shandong University, Jinan 250012, Shandong, China.

We assessed genetic and environmental effects on bone development of the hand and wrist, and on key anthropometric measures in Chinese young twins. In total, 139 monozygotic and 95 dizygotic twin pairs aged from 5 to 18 years were recruited. The twin correlations of total hand and wrist scores for monozygotic (MZ) and dizygotic (DZ) twins were 0.71 and 0.36, respectively. Bivariate model analysis showed moderate genetic correlations only for total skeletal maturity vs. weight and total skeletal maturity vs. waist circumference (r, 0.51 and 0.46, respectively). Our findings demonstrated that genetic factors played important roles in bone development of the hand and wrist in Chinese young twins, and that these genetic effects might be distinct from those influencing anthropometric measures.
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http://dx.doi.org/10.3967/bes2015.033DOI Listing
March 2015

Molecular phylogeny of Orthetrum dragonflies reveals cryptic species of Orthetrum pruinosum.

Sci Rep 2014 Jul 3;4:5553. Epub 2014 Jul 3.

Faculty of Science and Mathematics, Mataram University, Mataram, Indonesia.

Dragonflies of the genus Orthetrum are members of the suborder Anisoptera, family Libellulidae. There are species pairs whose members are not easily separated from each other by morphological characters. In the present study, the DNA nucleotide sequences of mitochondrial and nuclear genes were employed to elucidate the phylogeny and systematics of Orthetrum dragonflies. Phylogenetic analyses could not resolve the various subfamilies of the family Libellulidae unequivocally. The nuclear 28S rRNA gene is highly conserved and could not resolve congeneric species of Orthetrum. Individual mitochondrial genes (COI, COII, and 16S rRNA) and combination of these genes as well as the nuclear ITS1&2 genes clearly differentiate morphologically similar species, such as the reddish species pairs O. chrysis and O. testaceum, and the bluish-coloured species O. glaucum and O. luzonicum. This study also reveals distinct genetic lineages between O. pruinosum schneideri (occurring in Malaysia) and O. pruinosum neglectum (occurring north of Peninsular Malaysia from India to Japan), indicating these taxa are cryptic species.
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http://dx.doi.org/10.1038/srep05553DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5381552PMC
July 2014
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