Enhanced Delivery of F-, Ca2+, K+, and Na+ Ions into Enamel by Electrokinetic Flows.

As the outermost layer of the tooth crown, dental enamel is the most mineralized tissue in mammals, consisting of hydroxyapatite crystallites separated by long and narrow nanochannels. A major challenge in dentistry is how various molecules can be infiltrated into these nanopores in an efficient and controlled way. Here we show a robust method to transport various ions of interest, such as fluoride (F-), potassium (K+), calcium (Ca++), and sodium (Na+), into these nanopores by electrokinetic flows. It is verified by fluorescence microscopy, laser-scanning confocal microscopy, mass spectrometry, and ion selective electrode technique. Different ions are demonstrated to infiltrate through the entire depth of the enamel layer (~1 mm), which is significantly enhanced penetration compared with diffusion-based infiltration. Meanwhile, transport depth and speed can be controlled by infiltration time and applied voltage. This is the first demonstration of reliably delivering both anions and cations into the enamel nanopores. This technique opens opportunities in caries prevention, remineralization, tooth whitening, and nanomedicine delivery in clinical dentistry, as well as other delivery challenges into various biomaterials such as bones.

LncRNA GIHCG promotes development of ovarian cancer by regulating microRNA-429.

OBJECTIVE: To explore whether lncRNA GIHCG participates in the pathogenic progression of ovarian cancer (OC) and its underlying mechanism. PATIENTS AND METHODS: Expression levels of GIHCG and microRNA-429 in 30 OC tissues and normal ovarian tissues were detected by quantitative Real time-polymerase chain reaction (qRT-PCR). Subsequently, 15 pairs of OC tissues and paracancerous tissues were selected for correlation analyses of GIHCG, microRNA-429 and the overall survival (OS) of OC patients using Kaplan-Meier method. Pearson correlation analyses were conducted for investigating the correlation between GIHCG and microRNA-429. GIHCG expression in OC cell lines (HEY, A2780 and HO8910) and normal epithelial OC cell line (IOSE-386) was detected by qRT-PCR. After transfection of GIHCG overexpression plasmid in HEY cells, cell cycle, proliferation and colony formation ability were detected by flow cytometry, cell counting kit-8 (CCK-8) and colony formation assay. MicroRNA-429 expression in HEY cells overexpressing GIHCG was detected by qRT-PCR. Rescue experiments were conducted by co-transfection of GIHCG overexpression plasmid and microRNA-429 mimics, followed by cell cycle and colony formation detection. RESULTS: GIHCG was highly expressed, whereas microRNA-429 was lowly expressed in OC tissues than that of paracancerous tissues. OC patients with higher expression of GIHCG showed shorter OS than those with lower expression. However, OC patients with higher expression of microRNA-429 had longer OS than those with lower expression. GIHCG expression was positively correlated to microRNA-429. In vitro experiments showed that GIHCG was highly expressed in HEY, A2780 and HO8910 cells than that of IOSE-386 cells. GIHCG overexpression in HEY cells promoted cell cycle and colony formation abilities, which were reversed by microRNA-429 overexpression. CONCLUSIONS: GIHCG is highly expressed in OC, which promotes OC development by stimulating cell cycle progression and cell proliferation by regulating microRNA-429.

Silencing FOXA1 gene regulates liver cancer cell apoptosis and cell proliferation.

OBJECTIVE: Liver cancer emerged as a major health problem, and it accounts for leading cancer-related death worldwide. Due to recurrence and metastatic behavior, it is challenging to be controlled and managed. Understanding the regulative role of different proteins, which regulates liver cancer in various pathological stages, is essential to be investigated. In this study, we analyzed the correlation between Foxa1 suppression along with apoptosis and cancer stem cell proliferation. MATERIALS AND METHODS: CD133+ cells were used to induce the initial and advanced stage of liver cancer. Histology was used to study and confirm the tissue complications associated with initial, advanced and Foxa1 silenced liver cancer tissues. Immunohistochemistry and Western blotting were used to quantify Foxa1, CD133 expression. TUNEL assay was performed to study apoptosis. RESULTS: Initially using CD133+ cells, we successfully developed a mouse model with the initial and advanced stage of liver cancer upon 4 and 8 weeks incubation. Histologically, as the tumor progress, it shows more proliferative cells with disorganized tissue structure. Foxa1 silencing aids in recovering from initial liver cancer, but it has only limited effects with advanced liver cancer. The apoptosis process is enhanced in initial liver cancer, and Foxa1 silenced tissue when compared with the advanced stage of liver cancer. Foxa1 silencing also suppresses the cancer stem cell proliferation. CONCLUSIONS: Overall, our results reveal the critical role of Foxa1 in regulating apoptosis and liver cancer stem cells.

Crustal fluid and ash alteration impacts on the biosphere of Shikoku Basin sediments, Nankai Trough, Japan.

We present data from sediment cores collected from IODP Site C0012 in the Shikoku Basin. Our site lies at the Nankai Trough, just prior to subduction of the 19 Ma Philippine Sea plate. Our data indicate that the sedimentary package is undergoing multiple routes of electron transport and that these differing pathways for oxidant supply generate a complex array of metabolic routes and microbial communities involved in carbon cycling. Numerical simulations matched to pore water data document that Ca(2+) and Cl(1-) are largely supplied via diffusion from a high-salinity (44.5 psu) basement fluid, which supports the presence of halophile Archean communities within the deep sedimentary package that are not observed in shallow sediments. Sulfate supply from basement supports anaerobic oxidation of methane (AOM) at a rate of ~0.2 pmol cm(-3) day(-1) at ~400 mbsf. We also note the disappearance of δ-Proteobacteria at 434 mbsf, coincident with the maximum in methane concentration, and their reappearance at 463 mbsf, coinciding with the observed deeper increase in sulfate concentration toward the basement. We did not, however, find ANME representatives in any of the samples analyzed (from 340 to 463 mbsf). The lack of ANME may be due to an overshadowing effect from the more dominant archaeal phylotypes or may indicate involvement of unknown groups of archaea in AOM (i.e., unclassified Euryarchaeota). In addition to the supply of sulfate from a basement aquifer, the deep biosphere at this site is also influenced by an elevated supply of reactive iron (up to 143 µmol g(-1)) and manganese (up to 20 µmol g(-1)). The effect of these metal oxides on the sulfur cycle is inferred from an accompanying sulfur isotope fractionation much smaller than expected from traditional sulfate-reducing pathways. The detection of the manganese- and iron-reducer γ-Proteobacteria Alteromonas at 367 mbsf is consistent with these geochemical inferences.

Enhanced transport of materials into enamel nanopores via electrokinetic flow.

The ability to infiltrate various molecules and resins into dental enamel is highly desirable in dentistry, yet transporting materials into dental enamel is limited by the nanometric scale of their pores. Materials that cannot be infiltrated into enamel by diffusion/capillarity are often considered molecules with sizes above a critical threshold, which are often considered to be larger than the pores of enamel. We challenge this notion by reporting the use of electrokinetic flow to transport solutions with molecules with sizes above a critical threshold-namely, an aqueous solution with a high refractive index (Thoulet's solution) and a curable fluid resin infiltrant (without acid etching)-deep into the normal enamel layer. Volume infiltration by Thoulet's solution is increased by 5- to 6-fold, and resin infiltration depths as large as 600 to 2,000 µm were achieved, in contrast to ~10 µm resulting from diffusion/capillarity. Incubation with demineralization solution for 192 h resulted in significant demineralization at noninfiltrated histologic points but not at resin infiltrated. These results open new avenues for the transport of materials in dental enamel.

High-resolution ultrasound in the evaluation and prognosis of Bell's palsy.

INTRODUCTION: Bell's palsy is a commonly encountered paralysis of the facial nerve occurring worldwide. Prognosis for Bell's palsy is good, but the proportion of patients with poor outcomes may reach 30%. Ultrasound (US) may provide a novel approach for evaluating and prognosticating Bell's palsy, in comparison with known electrophysiological techniques. METHODS: In this study, we measured the diameter of the distal facial (VII) nerve using US in patients with Bell's palsy treated with prednisolone, in comparison with healthy controls. Blink reflex and VII nerve conduction studies were also performed. Studies were prospective and performed within 1 week of disease onset. RESULTS: Our results have shown that diameter of the distal VII nerve is a good predictor of favorable (positive predictive value: 100%) and bad outcomes (negative predictive value: 77%) in Bell's palsy at 3 months after clinical presentation. Furthermore, we also noted the lack of correlation of VII diameter with conventional VII nerve conduction studies (NCS) and blink reflex studies. US was superior to VII nerve conduction and blink reflex studies in outcome prediction. CONCLUSIONS: This first study utilizing US in Bell's palsy highlights its role in outcome prediction and contributes to our understanding of recovery processes in this common neurological disorder.

Micromixer based on viscoelastic flow instability at low Reynolds number.

We exploited the viscoelasticity of biocompatible dilute polymeric solutions, namely, dilute poly(ethylene oxide) solutions, to significantly enhance mixing in microfluidic devices at a very small Reynolds number, i.e., Re approximately 0.023, but large Peclet and elasticity numbers. With an abrupt contraction microgeometry (8:1 contraction ratio), two different dilute poly(ethylene oxide) solutions were successfully mixed with a short flow length at a relatively fast mixing time of <10 mus. Microparticle image velocimetry was employed in our investigations to characterize the flow fields. The increase in velocity fluctuation with an increase in flow rate and Deborah number indicates the increase in viscoelastic flow instability. Mixing efficiency was characterized by fluorescent concentration measurements. Our results showed that enhanced mixing can be achieved through viscoelastic flow instability under situations where molecular-diffusion and inertia effects are negligible. This approach bypasses the laminar flow limitation, usually associated with a low Reynolds number, which is not conducive to mixing.

Arterial stiffness, metabolic syndrome and inflammation amongst Asian ischaemic stroke patients.

BACKGROUND AND PURPOSE: Arterial stiffness and metabolic syndrome (MetS) are risk factors for ischaemic stroke. We studied the association of arterial stiffness, measured by carotid-femoral pulse wave velocity (PWV) and MetS amongst ischaemic stroke patients. We also investigated the role of inflammation measured by serum erythrocyte sedimentation rate (ESR) in the metabolic syndrome-arterial stiffness relationship. METHODS: Amongst the 229 prospectively recruited acute ischaemic stroke patients, we measured carotid-femoral PWV using applanation tonometry and the inflammatory marker serum ESR. RESULTS: Carotid-femoral PWV was significantly higher amongst patients with MetS (P = 0.002), increased waist circumference (P = 0.010), raised blood pressure (P < 0.001) and abnormal glycemia (P = 0.002); and increased with the number of MetS components (P = 0.002). In a sub-group of 199 patients, carotid-femoral PWV was significantly correlated with serum ESR (P < 0.001). In multivariate regression analysis including serum ESR and MetS as variables, carotid-femoral PWV was independently associated with higher ESR (P = 0.002) but not with MetS (P = 0.139). CONCLUSIONS: Arterial stiffness is significantly associated with MetS amongst ischaemic stroke patients, and inflammation appears to be involved in this relationship.

Rapid ultrasonographic diagnosis of radial entrapment neuropathy at the spiral groove.

BACKGROUND: Entrapment neuropathy of the radial nerve at the spiral groove region is relatively common. However, its localization may be technically challenging. OBJECTIVE: To evaluate the use of ultrasound (US), in relation to electrophysiological testing, for this purpose. METHODS: We studied 32 normal controls to obtain US parameters of the radial nerve. In addition, 10 patients with suspected radial neuropathy were tested using US and electrophysiological techniques. RESULTS: US examination correctly identified all 6 patients with radial neuropathy. The other 4 patients with alternate diagnoses did not show US abnormalities exceeding that of normal controls. US examination required a significantly shorter time than electrophysiological testing. CONCLUSIONS: US is of value as a rapid diagnostic adjunct for the localization of radial nerve entrapment.

Arterial stiffness is associated with raised levels of the inflammatory marker erythrocyte sedimentation rate among ischaemic stroke patients.

We studied the relationship of arterial stiffness, measured by carotid-femoral pulse wave velocity and inflammation, measured by serum erythrocyte sedimentation rate among 334 ischaemic stroke patients. There was a significant correlation between carotid-femoral pulse wave velocity and erythrocyte sedimentation rate (P = 0.001), a relationship independent of age, hypertension, diabetes and smoking. Arterial stiffness and inflammation are associated among ischaemic stroke patients and are independent of established vascular risk factors.

[Purification of proteins in human plasma with new nylon affinity membranes].

A series of affinity membranes were prepared by using microporous nylon membrane as matrix and activation method with s-triazine and 1,4-butanediol diglycidyl ether, separately. Three proteins with clinic value, gamma-globulin, plasminogen and thrombin, were purified from human plasma by one step with affinity membrane chromatography. The purities of gamma-globulin purified were higher than 83%, and purification folds were higher than 5. The purity of gamma-globulin obtained was higher than that of standard human gamma-globulin. The efficiencies of gamma-globulin purification with affinity membranes prepared by two activation methods were equal. Plasminogen purified with affinity membranes prepared by s-triazine activation was higher than that by 1,4-butanediol diglycidyl ether activation. And SDS-PAGE analysis showed that the purities of gamma-globulin and plasminogen obtained were higher than that of the commercial product. In addition, the purification of thrombin from human plasma by one step with trypsin activation column and affinity membrane was studied. Thrombin with specific activity of 42 NIH unit/mg and 42.5 NIH unit/mg could be obtained from human plasma through affinity membranes prepared by s-triazine and 1,4-butanediol diglycidyl ether methods, respectively.

New affinity nylon membrane used for adsorption of gamma-globulin.

Microporous polyamide membranes were first modified by acid hydrolysis and subsequently bound with hydroxy-ethylcellulose to amplify reactive groups and reduce nonspecific interactions with proteins. Then 1,6-diaminohexane as space arm and phenylalanine as ligand were immobilized onto the nylon membranes by s-triazine trichloride activation. Affinity membranes thus obtained were set in a stack and used to adsorb gamma-globulin. The adsorption capacity (qm) of the affinity membrane is 53 micro gamma-globulin per m2 membrane and the desorption constant (Kd) is 2.35 x 10(-6) mol/l. The effects of feed, washing and elution rates on adsorption and desorption behavior were investigated. The results showed that affinity purification through these membranes could not be operated at very high flow-rates. A stack of 20 membranes with 47 mm diameter can adsorb 7.8 mg gamma-globulin with a purity of 91.6% from 4 ml of human plasma in a single-pass mode.