Effect of local watershed landscapes on the nitrogen and phosphorus concentrations in the waterbodies of reservoir bays

Reservoir bays, which are affected by the reservoir and watershed characteristics, are the initial and most sensitive areas in the evolution process of reservoir water quality. However, the relationship between the watershed characteristics and nitrogen and phosphorus concentrations in reservoir bays is poorly understood. We selected 66 bays from the Danjiangkou Reservoir and sampled twice per year (storage and discharge periods) from 2015 to 2018 to monitor the total nitrogen (TN) and total phosphorus (TP) concentration in the waterbodies of the reservoir bays. Four types of watershed characteristic indices (topographic variables, soil variables, land-use composition, and landscape patterns) around these bays were obtained. We quantified the relationship between the TN and TP concentrations and watershed characteristics in the waterbodies of the reservoir bays using partial least squares regression (PLSR). The results showed that the mean concentrations of TN and TP in the storage period (TN:1.69 mg·L^-1, TP:0.088 mg·L^-1) were higher than those in the discharge period (TN:1.22 mg·L^-1, TP:0.063 mg·L^-1). The optimal PLSR models explained 67.9% and 82.5% of the TN concentration variability, and 65.4% and 67.2% of the TP concentration variability during the storage and discharge period, respectively. Based on the variable importance in the projection (VIP) values, soil erodibility had significant effects on the TN and TP concentrations. The key factors affecting the TN concentration were the slope gradient, basin relief, topographic wetness index, forest and agricultural land use, whereas the factors controlling the TP concentration were the landscape shape index, edge density, Shannon's diversity index and grass land use, although the TP concentration was also controlled by the patch density and contagion during the storage period, and by mean patch size and largest patch index during the discharge period. This study provides critical insights into sustainable landscape planning and effective reservoir water quality management.

Follicle-Stimulating Hormone β-Subunit Potentiates Bone Morphogenetic Protein 9-Induced Osteogenic Differentiation in Mouse Embryonic Fibroblasts

Postmenopausal osteoporosis (PMOP)-related fractures usually result in morbidity and mortality in aging women, so it remains a global public health concern, and new effective safe treatments are urgently needed recently. Efficient osteogenesis from mesenchymal stem cells (MSCs) would have the clinical application potential in treating multiple osteal disorders. Follicle-stimulating hormone (FSH), a pituitary glycoprotein hormone highly associated with menopausal bone turnover, whose peculiar part of receptor binding is follicle-stimulating hormone β-subunit (FSHβ). Bone morphogenetic protein 9 (BMP9), a potent osteogenic factor, can up-regulate FSHβ in mouse embryonic fibroblasts (MEFs). However, it is unclear, whether extrapituitary FSHβ affects BMP9-induced osteogenesis in MEFs. In this study, we investigated the role of FSHβ in BMP9-induced osteogenesis in MEFs. We found that exogenous expression of FSHβ significantly increased BMP9-induced alkaline phosphatase activity (ALP), the expression of osteogenic transcriptional factors, Runx2 and Osx, and the established late osteogenic markers, osteopontin (OPN) and osteocalcin (OCN), so does the ectopic bone formation. Mechanistically, FSHβ dramatically enhanced BMP9-induced BMP/Smad signal transduction, presenting the augment phosphorylation of Smad1/5/8, whereas treatment with anti-FSHβ antibodies suppressed these effects. An adenylate cyclase inhibitor obviously suppressed ALP and BMP/Smad signal transduction induced by BMP9 or the combination of BMP9 and FSHβ in MEFs. Collectively, our findings suggested that FSHβ may promote BMP9-induced activation of BMP/Smad signaling through a FSH/FSH receptor (FSHR)/cAMP dependent pathway in MEFs partly. J. Cell. Biochem. 118: 1792-1802, 2017. © 2016 Wiley Periodicals, Inc.

TGF-β1/PTEN/PI3K signaling plays a critical role in the anti-proliferation effect of tetrandrine in human colon cancer cells

The diagnosis and treatment for colon cancer have been greatly developed, but the prognosis remains unsatisfactory. There is still a great clinical need to explore new efficacious drugs for colon cancer treatment. Tetrandrine (Tet) is a bis-benzylisoquinoline alkaloid. It has been shown that Tet may be a potential candidate for cancer treatment, but the explicit mechanism underlying this activity remains unclear. In this study, we investigated the anticancer activity of Tet in human colon cancer cells and dissected the possible mechanism. With cell viability assay and flow cytometry analysis, we confirmed that Tet can effectively inhibit the proliferation and induce apoptosis in HCT116 cells. Mechanically, we found that Tet greatly increases the mRNA and protein level of TGF-β1 in HCT116 cells. Exogenous TGF-β1 enhances the anti-proliferation and apoptosis inducing effect of Tet in HCT116 cells, which has been partly reversed by TGF-β1 inhibitor. Tet decreases the phosphorylation of Akt1/2/3 in HCT116 cells. This effect can be enhanced by exogenous TGF-β1, but partly reversed by TGF-β1 inhibitor. Tet exhibits no effect on total level of PTEN, but decreases the phosphorylation of PTEN; exogenous TGF-β1 enhances the effect of Tet on decreasing the phosphorylation of PTEN, which was partly reversed by TGF-β1 inhibitor. Our findings suggested that Tet may be a promising candidate for colon cancer treatment, and the anticancer activity may be mediated by inactivating PI3K/Akt signaling through upregulating TGF-β1 to decrease the phosphorylation of PTEN.

Ursolic acid inhibits proliferation and induces apoptosis by inactivating Wnt/β-catenin signaling in human osteosarcoma cells

Although multiple chemotherapeutic agents have been used for osteosarcoma (OS) treatment, their mechanisms need further study. Ursolic acid (UA), a pentacyclic triterpenoid, can reduce cell proliferation and induce apoptosis in various cancer cells, such as OS. However, the exact mechanism underlying this function remains unclear. In this study, we investigated the anti‑proliferative effect of UA in human OS 143B cells and dissected the possible molecular mechanism underlying this effect. We demonstrated that UA can reduce cell proliferation, induce apoptosis and arrest cell cycle in 143B cells, as well as inhibit OS tumor growth in a mouse xenograft model. Using a luciferase reporter assay, we found that the Wnt/β‑catenin signaling is inhibited by UA in 143B cells. Correspondingly, the expression level and nuclear translocation of β‑catenin are both decreased by UA. Exogenous expression of β‑catenin attenuates the anticancer effect of UA in 143B cells, while knockdown of β‑catenin enhances this effect. UA increases the expression level of p53 in a concentration‑dependent manner, and inhibition of p53 reduces the anticancer effect of UA in 143B cells. Moreover, inhibition of p53 partly reverses the UA‑induced downregulation of β‑catenin, as do the targets of Wnt/β‑catenin signaling, such as c‑Myc and cyclin D1. Our findings indicated that UA can inhibit the proliferation of 143B OS cells through inactivation of Wnt/β-catenin signaling, which may be mediated partly by upregulating the expression of p53.

All-trans retinoic acid shifts rosiglitazone-induced adipogenic differentiation to osteogenic differentiation in mouse embryonic fibroblasts

Rosiglitazone (RSG) is a potent drug used in the treatment of insulin resistance; however, it is associated with marked skeletal toxicity. RSG-induced osteoporosis may contribute to the promotion of adipogenic differentiation at the expense of osteogenic differentiation in bone marrow stromal cells. The aim of this study was to investigate whether RSG-induced bone toxicity can be reversed by combined treatment with all-trans retinoic acid (ATRA). We examined different osteogenic markers in mouse embryonic fibroblasts (MEFs) following treatment with RSG, ATRA, or RSG and ATRA in combination. We examined the effects of RSG and/or ATRA on ectopic bone formation, and dissected the possible molecular mechanisms underlying this process. We found that ATRA or RSG both induced alkaline phosphatase (ALP) activity in the MEFs, and that the ATRA-induced ALP activity was enhanced by RSG and vice versa. However, only the combination of RSG and ATRA increased the expression of osteopontin and osteocalcin, promoted matrix mineralization, and induced ectopic ossification in MEFs. Mechanistically, we found that the osteogenic differentiation induced by the combination of RSG and ATRA may be mediated partly by suppressing RSG-induced adipogenic differentiation and activating bone morphogenetic protein (BMP)/Smad signaling. On the whole, our findings demonstrate that RSG in combination with ATRA promotes the commitment of MEFs to the osteoblast lineage. Thus, the combination of these two agents may prove to be a promising and novel therapeutic regimen for insulin resistance without skeletal toxicity. It may also be a better strategy with which to prevent RSG-induced osteoporosis.

Antiproliferation effect of evodiamine in human colon cancer cells is associated with IGF-1/HIF-1α downregulation

Colon cancer is one of the most common malignancies. Although the current treatment regimes for colon cancer have been well-developed in the past decades, the prognosis remains still undesirable. It is still urgent to explore new treatment strategies for colon cancer. Natural products is one of the most useful sources for anticancer agents, although some of them have serious side-effects. Evodiamine (Evo) is an quinolone alkaloid from the traditional herb medicine Evodia rutaecarpa. In the present study, we investigated the anticancer effect of Evo in human colon cancer cells. We found that Evo exhibits prominent antiproliferation and apoptosis inducing effects in LoVo cells. Evo leads to apparent downregulation of HIF-1α either in vitro or in vivo; exogenous expression of HIF-1α can attenuate the antiproliferation effect of Evo in LoVo cells, while HIF-1α knockdown potentiates this effect greatly. Further analysis indicated that Evo can also inhibit the phosphorylation of Akt1/2/3 and decrease greatly the expression of IGF-1. Thus, our findings strongly suggested that the anticancer effect of Evo in human colon cancer may be partly mediated by downregulating HIF-1α expression, which is initiated by inactivating PI3K/Akt signaling transduction though decreasing the expression of IGF-1 in colon cancer cells. Therefore, Evo may be used alone or in combination as a potential anticancer agent for colon cancer treatment.

Prevalence, characteristics and natural history of cold intolerance after the reverse digital artery flap

This retrospective study was designed to investigate the prevalence, characteristics and natural history of cold intolerance after the use of the reverse digital artery flap. A total of 123 patients were treated between 2010 and 2013. After excluding patients who were lost to follow-up, 87 patients were studied. The mean follow-up time was 34 months (range 14-61). Cold intolerance occurred in 60% (52) of patients after the reverse digital artery flap procedure. The condition improved in only 15% (8) of the patients. Significant differences were observed in the age and the specific digit involved between the groups with and without cold intolerance. There was a lower incidence in younger patients, and the ring finger group showed a lower incidence than in other fingers. Furthermore, the Cold Intolerance Symptom Severity score was positively correlated with the temperature at which cold intolerance was triggered.

LEVEL OF EVIDENCE

IV.

Comparative study of functional and aesthetically outcomes of reverse digital artery and reverse dorsal homodigital island flaps for fingertip repair

This retrospective study was designed to compare functional and cosmetic outcomes of the reverse digital artery island flap and reverse dorsal homodigital island flap in fingertip repair. A total of 23 patients were followed for 24 to 30 months. The reverse digital artery island flap was used in 12 patients, and reverse dorsal homodigital island flap in another 11 patients. Flap sensibility was assessed using the Semmes-Weinstein monofilament test and static 2-point discrimination test. Patient satisfaction, active motion of the finger joints, complications and cold intolerance were evaluated. The static 2-point discrimination and Michigan Hand Outcomes Questionnaire (appearance) of the fingers treated with a reverse digital artery flap were significantly better than those with a reverse dorsal homodigital flap. The static 2-point discrimination of the skin-grafted donor sides after dorsal homodigital flap were poorer than that in the contralateral finger. No significant differences were found between the two flaps for pressure or touch sensibility, active ranges of digital motion, complications and cold intolerance.

LEVEL OF EVIDENCE

III.

Bioglass-derived glass-ceramic scaffolds: study of cell proliferation and scaffold degradation in vitro

Cell support function as well as cell proliferation on highly porous Bioglass(R)-derived glass-ceramic scaffolds (designed for bone tissue engineering) have been assessed in vitro using osteoblast-like cells (MG 63) cultured for up to 6 days. The biodegradation and mechanical stability of the scaffolds in the cell-culture medium have also been investigated. It was found that the scaffolds had excellent cell supporting ability, with cells effectively infiltrating into and surviving at the center of the scaffolds. A quantitative study using the AlamarBlue assay revealed that the proliferation of cells on the glass-ceramic materials was comparable to that on the noncrystallized Bioglass. While the crystalline phase in the glass-ceramic scaffolds transformed into a biodegradable amorphous calcium phosphate phase during cell culture, the mechanical strength of the scaffolds was maintained when compared with that of scaffolds incubated in simulated body fluid or immersed in cell-free culture medium. It is believed that the attached cells and collagen secreted by cells could fill the micropores and microcracks on the surface of the foam struts, thus contributing to the mechanical stability of the degrading scaffolds. In summary, the developed glass-ceramic scaffolds possess the most essential features of a scaffold for bone tissue engineering: they are capable to support and foster relevant cells, able to provide temporary mechanical function, and biodegradable.

Myocardial tissue engineering: a review

Myocardial tissue engineering, a concept that intends to overcome the obstacles to prolonging patients' life after myocardial infarction, is continuously improving. It comprises a biomaterial based 'vehicle', either a porous scaffold or dense patch, made of either natural or synthetic polymeric materials, to aid transportation of cells into the diseased region in the heart. Many different cell types have been suggested for cell therapy and myocardial tissue engineering. These include both autologous and embryonic stem cells, both having their advantages and disadvantages. Biomaterials suggested for this specific tissue-engineering application need to be biocompatible with the cardiac cells and have particular mechanical properties matching those of native myocardium, so that the delivered donor cells integrate and remain intact in vivo. Although much research is being carried out, many questions still remain unanswered requiring further research efforts. In this review, we discuss the various approaches reported in the field of myocardial tissue engineering, focusing on the achievements of combining biomaterials and cells by various techniques to repair the infarcted region, also providing an insight on clinical trials and possible cell sources in cell therapy. Alternative suggestions to myocardial tissue engineering, in situ engineering and left ventricular devices are also discussed.

Vaterite deposition on biodegradable polymer foam scaffolds for inducing bone-like hydroxycarbonate apatite coatings

Hydroxycarbonate apatite (HCA) coatings on the surface of bioresorbable materials for bone tissue engineering scaffolds were produced using macroporous poly(DL-lactide) (PDLLA) foams impregnated by calcium carbonate in vaterite crystalline form. Stable and homogeneous vaterite deposition on PDLLA foams was achieved using a slurry dipping technique. In vitro studies in simulated body fluid (SBF) were performed to induce formation of (HCA) on the surface of vaterite/PDLLA composite foams. HCA was detected after immersion of foams in SBF for 7 days. Hence, depositing vaterite on materials followed by immersion in SBF is confirmed to induce HCA coatings on the surface of the material. The HCA coated, bioactive and resorbable PDLLA foams are intended for use as bone tissue engineering scaffolds.

Poly(D,L-lactic acid) coated 45S5 Bioglass-based scaffolds: processing and characterization

A comparative investigation has been carried out on the mechanical properties and bioactivity of Bioglass-based foams, before and after applying a poly(D,L-lactic acid) (PDLLA) coating layer on the foam struts. It was found that the bioactivity of foams upon immersion in simulated body fluid (SBF) was maintained in the PDLLA-coated foams; however, the transformation kinetics in SBF of the crystalline phase (Na(2)Ca(2)Si(3)O(9)) in the foam struts to an amorphous calcium phosphate phase was retarded by PDLLA coating. The compressive and three-point bending strengths of the Bioglass-based foams were slightly improved by the PDLLA-coating, and the work-of-fracture of the foams was considerably enhanced, as indicated by stress-strain curves. Immersion in SBF for 4 weeks led to a large decrease of the mechanical strength of as-sintered foams decreased (from 0.3 to 0.03 MPa), because of the transformation of the crystalline phase to an amorphous calcium phosphate. On the other hand, the mechanical strength was well-maintained in PDLLA-coated foams after immersion in SBF for 8 weeks. This behavior was attributed to the in-situ formation of a nanocomposite PDLLA/calcium phosphate film on the strut surfaces upon immersion in SBF.

The surface functionalization of 45S5 Bioglass-based glass-ceramic scaffolds and its impact on bioactivity

The first and foremost function of a tissue engineering scaffold is its role as a substrate for cell attachment, and their subsequent growth and proliferation. However, cells do not attach directly to the culture substrate; rather they bind to proteins that are adsorbed to the scaffold's surface. Like standard tissue culture plates, tissue engineering scaffolds can be chemically treated to couple proteins without losing the conformational functionality; a process called surface functionalization. In this work, novel highly porous 45S5 Bioglass-based scaffolds have been functionalized applying 3-AminoPropyl-TriethoxySilane (APTS) and glutaraldehyde (GA) without the use of organic solvents. The efficiency and stability of the surface modification was assessed by X-ray photoemission spectroscopy (XPS). The bioactivity of the functionalized scaffolds was investigated using simulated body fluid (SBF) and characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). It was found that the aqueous heat-treatment applied at 80 degrees C for 4 hrs during the surface functionalization procedure accelerated the structural transition of the crystalline Na2Ca2Si3O9 phase, present in the original scaffold structure as a result of the sintering process used for fabrication, to an amorphous phase during SBF immersion. The surface functionalized scaffolds exhibited an accelerated crystalline hydroxyapatite layer formation upon immersion in SBF caused by ion leaching and the increased surface roughness induced during the heat treatment step. The possible mechanisms behind this phenomenon are discussed.

Biodegradable and bioactive porous polymer/inorganic composite scaffolds for bone tissue engineering

Biodegradable polymers and bioactive ceramics are being combined in a variety of composite materials for tissue engineering scaffolds. Materials and fabrication routes for three-dimensional (3D) scaffolds with interconnected high porosities suitable for bone tissue engineering are reviewed. Different polymer and ceramic compositions applied and their impact on biodegradability and bioactivity of the scaffolds are discussed, including in vitro and in vivo assessments. The mechanical properties of today's available porous scaffolds are analyzed in detail, revealing insufficient elastic stiffness and compressive strength compared to human bone. Further challenges in scaffold fabrication for tissue engineering such as biomolecules incorporation, surface functionalization and 3D scaffold characterization are discussed, giving possible solution strategies. Stem cell incorporation into scaffolds as a future trend is addressed shortly, highlighting the immense potential for creating next-generation synthetic/living composite biomaterials that feature high adaptiveness to the biological environment.

Bioactive and mechanically strong Bioglass®-poly(D,L-lactic acid) composite coatings on surgical sutures

New coating processes have been investigated for degradable (Vicryl) and nondegradable (Mersilk) sutures with the aim to develop Bioglass coated polymer fibers for wound healing and tissue engineering scaffold applications. First, the aqueous phase of a Bioglass particle slurry was replaced with a poly(D,L-lactic acid) (PDLLA) polymer dissolved in solvent dimethyle carbonate (DMC) to act as third phase. SEM observations indicated that this alteration significantly improved the homogeneity of the coatings. Second, a new coating strategy involving two steps was developed: the sutures were first coated with a Bioglass-PDLLA composite film followed by a second PDLLA coating. This two-step process of coating has addressed the problem of poor adherence of Bioglass particles on suture surfaces. The coated sutures were knotted to determine qualitatively the mechanical integrity of the coatings. The results indicated that adhesion strength of coatings obtained by the two-step method was remarkably enhanced. A comparative assessment of the bioactivity of one-step and two-step produced coatings was carried out in vitro using acellular simulated body fluid (SBF) for up to 28 days. Coatings produced by the two-step process were found to have similar bioactivity as the one-step produced coatings. The novel Bioglass/PDLLA/Vicryl and Bioglass/PDLLA/Mersilk composite sutures are promising bioactive materials for wound healing and tissue engineering applications.

Strengthening mechanisms of bone bonding to crystalline hydroxyapatite in vivo

The formation and strengthening mechanisms of bone bonding of crystalline hydroxyapatite (HA) has been investigated using high-resolution transmission electron microscope (HRTEM) and energy-dispersive X-ray (EDX) analysis. A series of results were obtained: (i) a layer of amorphous HA, which has almost the same chemistry as the implanted HA, was formed on the surface of crystalline HA particles prior to dissolution; (ii) at 3 months a bone-like tissue formed a bonding zone between mature bone and the HA implant, composed of nanocrystalline and amorphous apatite; and (iii) at 6 months, mature bone was in direct contact with HA particles, and collagen fibres were perpendicularly inserted into the surface layer of implanted HA crystals. Findings (i) and (ii) indicated the following dissolution-precipitation process. (i) The crystalline HA transforms into amorphous HA; (ii) the amorphous HA dissolves into the surrounding solution, resulting in over-saturation; and (iii) the nanocrystallites are precipitated from the over-saturated solution in the presence of collagen fibres. A preliminary analysis indicated several conclusions: (i) the transition from crystalline to amorphous HA might be the controlling step in the bone bonding of crystalline HA; (ii) biological interdigitation (or incorporation) of collagen fibres with HA and chemical bonding of a apatite layer were both necessary to strengthen and toughen a bone bond, not only for the bonding between bone and HA at 6 months, but also for the bonding zone at 3 months, which would otherwise be very fragile due to the inherited brittleness of polycrystalline ceramics; and (iii) perpendicular interdigitation is an effective way for collagen fibres to impart their unique combination of flexibility and strength to the interface which they are keying.

Ultrastructural study of mineralization of a strontium-containing hydroxyapatite (Sr-HA) cementin vivo

The purpose of this study was to investigate the mineralization leading to osseointegration of strontium-containing hydroxyapatite (Sr-HA) bioactive bone cement injected into cancellous bone in vivo. Sr-HA cement was injected into the ilium of rabbits for 1, 3, and 6 months. The bone mineralization area was found to be largest at 3 months, then at 1 month, and smallest at 6 months (p < 0.01) measured with tetracycline labeling. Osseointegration of Sr-HA cement was achieved at 3 months as observed by scanning electron microscopy. A high calcium and phosphorus area was observed at the interface of bone-Sr-HA cement determined by energy-dispersive X-ray analysis. Transmission electron microscopy gave evidence of the mechanism of bone formation. Dissolution of Sr-HA into debris by the bone remodeling process was thought to increase the concentration of calcium and phosphorus at the interface of bone-Sr-HA cement and stimulate bone formation. Crystalline Sr-HA formed an amorphous layer and dissolved into the surrounding solution, then apatite crystallites were precipitated and formed new bone at 3 months. This young bone then becomes mature bone, which bonds tightly to the Sr-HA cement with collagen fibers inserted perpendicularly after 6 months.

[The changes in retinol-binding protein, N-acetyl-beta-glucosaminidase, albumin and IgG in urine before and after ESWL]

The retinol-binding protein (RBP), N-acetyl-beta-glucosaminidase, (NAG) albumin (alb) and IgG in urine were measured from 67 patients with urinary stone before and after ESWL. The results showed that the amount of alb, IgG and RBP in urine was obviously increased for the patients with renal, upper ureteral or lower ureteral stone associated with hydronephrosis. ESWL may injure the glomerule and tubules by direct or indirect action. 2 weeks after ESWL, the alb, IgG and RBP in urine returned to normal in 56.8%, 70.3% and 51.4% of cases respectively. Therefore we suggest that retreatment should be put off as late as 2 weeks after the first ESWL. However, it is not limited for retreatment of lower ureteral stones without hydro nephrosis.

[Diagnostic value of imaging in localizing primary aldosteronism]

From May 1985 to March 1993, 159 patients with primary aldosteronism were treated surgically. The results of localization of aldosteronomas by B-type ultrasonography, CT and scintigraphy in 103 were compared with pathological results. The accurate rate of the modalities was 80.6%, 75.8% and 67.4% respectively. As a routine, we usually employ sonography and CT for localizing aldosteronomas. Only when difficulty was encountered with these two methods, scintigraphy was added. In our series, an accurate rate of 96.1% was obtained in surgical explorations with these imaging examinations with a consideration of clinical data.