Two-dimensional polyimide heterojunctions for the efficient removal of environmental pollutants under visible-light irradiation.

Two-dimensional (2D) heteromaterials with large interface contact and intimate interfacial charge transition have been considered to be an ideal model for constructing highly efficient photocatalysts. However, few studies have reported on these 2D heterojunctions. Herein, we report a series of new 2D heterojunctions comprising polyimide (PI) and perylene-3,4,9,10-tetracarboxylic dianhydride (TD). These heterojunctions, denoted as PI-TDx (where x represents the amount of TD added, i.e., x = 0.13, 0.18, 0.27, 0.54, and 1.08 g), were prepared by the solid thermal copolymerization of melamine (MA), pyromellitic dianhydride (PD), and different amounts of TD. FT-IR spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and transmission electron microscopy analyses were used to verify the 2D heterojunction structure. Photocatalytic experiments reveal that PI-TDx exhibit excellent and stable photocatalytic performance for the degradation of the organic dyes rhodamine B (RhB) and methyl violet (MV), as well as for the photoreduction of Cr(vi), under visible-light irradiation. Among the samples, PI-TD0.18 exhibits the best photocatalytic performance. Its activity is about 2.7 times and 7.5 times higher than that of individual PIMP (formed by MA and PD) and PIMT (formed by MA and TD) for RhB degradation, respectively. Notably, PI-TD0.18 retains a certain photocatalytic activity under light irradiation at 600 nm. The photocatalytic-mechanism study demonstrates that PI-TD0.18 has a classic type-II heterojunction. Its 2D heterojunction greatly enhances the visible-light absorption of the composites and effectively suppresses the radiation recombination of photogenerated carriers, thereby improving its charge transfer and separation abilities and providing excellent photocatalytic performance. This work may serve as an important reference for the design and construction of new highly efficient 2D organic conjugated-polymer photocatalysts.

Association Between Helicobacter pylori Infection and Risk of Periodontal Diseases in Han Chinese: A Case-Control Study.

BACKGROUND: This study was performed to test the association between Helicobacter pylori (HP) and periodontal disease (PD). MATERIAL/METHODS: This was a case-control study in a comprehensive hospital, including all patients with newly diagnosed PD between 2012 and 2014 as cases and all patients without PD as controls, thorough periodontal examinations. Those who tested positive for HP were examined by means of polymerase chain reaction. Single and multivariate logistic regression was used to analyze the data using SPSS 19.0 software. RESULTS: This case-control study included 212 Han Chinese non-smoking adults. The results indicated that HP-positive status significantly increased the risk of PD (2.63 times higher (odds ratio [OR]=2.63; 95% confidence interval [CI]=1.48-4.67). After adjustment for age, sex, level of education, physical exercise, body mass index, and history of alcohol and diabetes mellitus, this association remained significantly (OR=2.82, 95% CI=1.55-5.13). CONCLUSIONS: PD might be associated with HP infection in adults and HP infection may be a significant and independent risk factor for PD.

Comparative study of covered stent with coil embolization in the treatment of cranial internal carotid artery aneurysm: a nonrandomized prospective trial.

To evaluate whether Willis covered stent implantation yielded angiographic and clinical results were better than those with coil embolization. Eighty-nine patients with cranial internal carotid artery (CICA) aneurysms were treated nonrandomly with covered stents (n = 43, group A) or coil embolization (n = 46, group B). Data on the technical success, procedure time, initial and final angiographic results, and final clinical outcomes were collected and analyzed at >6 months post-procedure. Covered stent placement and coil embolization were successful in all patients, except for one patient in group A. The initial angiographic results showed complete occlusion in 34 group-A patients (80.9%; 95% CI: 69%, 93%) and 24 group-B patients (52.2%; 95% CI: 37%, 67%) (P = 0.004). The final angiographic results indicated complete occlusion in 39 group A patients (39/41, 95.1%; 95% CI: 88%, 102%) and 22 group B patients (48.9%; 95% CI: 34%, 64%) (P < 0.001). The average procedure time was shorter in group A than that in group B (P < 0.001). CICA aneurysm treatment with covered stents yielded better intermediate-term angiographic outcome than those with the recommended approach of coil embolization. (ClinicalTrials.gov number, NCT01029938).

A feasibility study on laser rapid forming of a complete titanium denture base plate.

This work attempted to integrate the technologies of computer-aided design and computer-aided manufacture (CAD/CAM) and laser rapid forming (LRF) for the fabrication of the titanium plate of a complete denture. By the combination of laser scan and reverse engineering software, the standard triangulation language (STL)-formatted denture base plate was finally designed and sliced into a sequence of numerical controlled codes. The titanium (Ti) complete denture plate was finally built, layer-by-layer, on the LRF system. To evaluate the quality of fit, a virtual adaptation test that measured and compared the profiles of the laser free formed denture plate and those of the edentulous plaster cast had been conducted, and the mean deviation was found to be 0.34 mm. After traditional dental finishing techniques, a complete denture with a Ti base plate was then made and judged to be acceptable. The CAD/CAM/LRF system is a potential candidate and a new platform for the design and manufacture of custom-made Ti denture plates and restorations.

Evaluation of BP-M-CPF4 polyhydroxyalkanoate (PHA) synthase on the production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) from plant oil using Cupriavidus necator transformants.

Among the various types of polyhydroxyalkanoate (PHA), poly[(R)-3-hydroxybutyrate-co-(R)-3-hydroxyhexanoate] [P(3HB-co-3HHx)] has a high potential to serve as commercial bioplastic due to its striking resemblance to petroleum-based plastics. In this study, five different genotypes of Cupriavidusnecator transformants harbouring the phaCBP-M-CPF4 gene (including PHB¯4/pBBR1-CBP-M-CPF4) were developed to evaluate the efficiency of 3HHx monomer incorporation. The fraction of 3-hydroxyhexanoate (3HHx) monomer that was incorporated into the PHA synthesized by these C. necator transformants using palm oil as the sole carbon source, was examined. Overall, co-expression of enoyl-CoA hydratase gene (phaJ1) from Pseudomonas aeruginosa, along with PHA synthase (PhaC), increased the 3HHx composition in the PHA copolymer. The differences in the enzyme activities of ß-ketothiolase (PhaACn) and NADPH-dependent acetoacetyl-CoA reductase (PhaBCn) of the C. necator mutant hosts used in this study, were observed to alter the 3HHx composition and molecular weight of the PHA copolymer produced. The 3HHx fractions in the P(3HB-co-3HHx) produced by these C. necator transformants ranged between 1 and 18 mol%, while the weight-average molecular weight ranged from 0.7 × 106 to 1.8 × 106 Da. PhaCBP-M-CPF4 displayed a typical initial lag-phase and a relatively low synthase activity in the in vitro enzyme assay, which is thought to be the reason for the higher molecular weights of PHA obtained in this study.

Treatment of distal internal carotid artery aneurysm with the willis covered stent: a prospective pilot study.

PURPOSE: To evaluate the flexibility and efficacy of the Willis covered stent in the treatment of distal internal carotid artery (DICA) aneurysms. MATERIALS AND METHODS: The study was approved by the authors' institutional review board, and the research was conducted by the authors' institution and the MicroPort Medical Company (Shanghai, China). Thirty-one patients with 33 DICA aneurysms were considered for treatment with a Willis covered stent. The angiographic assessments were categorized as complete or incomplete occlusion. The data on technical success, initial and final angiographic results, mortality, morbidity, and final clinical outcome were collected, and follow-up was performed at 1, 3, 6, and 12 months and yearly after the procedures. RESULTS: Navigation and deployment of the covered stents were successful in 97.6% (41 of 42; 95% confidence interval [CI]: 93%, 102%) of the attempted stent placement procedures. The initial angiographic results showed a complete occlusion in 23 patients with 25 aneurysms (of 32 aneurysms, 78.1% [95% CI: 63%, 93%]) and an incomplete occlusion in seven patients with seven aneurysms (21.9%). The angiographic follow-up (mean, 14 months [95% CI: 12, 15 months]) findings exhibited a complete occlusion in 27 patients with 29 aneurysms (of 31 aneurysms, 93.5% [95% CI: 84%, 103%]) and an incomplete occlusion in two aneurysms (6.5%), with a mild in-stent stenosis in two patients. The clinical follow-up (mean, 27 months [95% CI: 23, 30 months]) demonstrated that 15 patients experienced a full recovery and 14 patients improved. CONCLUSION: The preliminary results demonstrate good flexibility and efficacy of the Willis covered stent in the treatment of DICA aneurysms in selected patients; longer follow-up and expanded clinical trials are needed.

Preclinical characteristics of the hepatitis C virus NS3/4A protease inhibitor ITMN-191 (R7227).

Future treatments for chronic hepatitis C virus (HCV) infection are likely to include agents that target viral components directly. Here, the preclinical characteristics of ITMN-191, a peptidomimetic inhibitor of the NS3/4A protease of HCV, are described. ITMN-191 inhibited a reference genotype 1 NS3/4A protein in a time-dependent fashion, a hallmark of an inhibitor with a two-step binding mechanism and a low dissociation rate. Under preequilibrium conditions, 290 pM ITMN-191 half-maximally inhibited the reference NS3/4A protease, but a 35,000-fold-higher concentration did not appreciably inhibit a panel of 79 proteases, ion channels, transporters, and cell surface receptors. Subnanomolar biochemical potency was maintained against NS3/4A derived from HCV genotypes 4, 5, and 6, while single-digit nanomolar potency was observed against NS3/4A from genotypes 2b and 3a. Dilution of a preformed enzyme inhibitor complex indicated ITMN-191 remained bound to and inhibited NS3/4A for more than 5 h after its initial association. In cell-based potency assays, half-maximal reduction of genotype 1b HCV replicon RNA was afforded by 1.8 nM; 45 nM eliminated the HCV replicon from cells. Peginterferon alfa-2a displayed a significant degree of antiviral synergy with ITMN-191 and reduced the concentration of ITMN-191 required for HCV replicon elimination. A 30-mg/kg of body weight oral dose administered to rats or monkeys yielded liver concentrations 12 h after dosing that exceeded the ITMN-191 concentration required to eliminate replicon RNA from cells. These preclinical characteristics compare favorably to those of other inhibitors of NS3/4A in clinical development and therefore support the clinical investigation of ITMN-191 for the treatment of chronic hepatitis C.

Trans-arterial embolisation therapy of dural carotid-cavernous fistulae using low concentration n-butyl-cyanoacrylate.

BACKGROUND: Trans-venous embolisation has been accepted as the preferred treatment for dural carotid-cavernous fistulae (DCCF). However, such an approach is not always feasible. In this circumstance, trans-arterial embolisation with low concentration n-butyl-cyanoacrylate glue (NBCA) may be a feasible alternative. We report our results and experience of this method for DCCF. MATERIALS AND METHODS: Five patients with DCCF were treated by trans-arterial embolisation using low concentration NBCA by wedging the microcatheter into the main feeding artery. All five lesions were associated with venous drainage into the superior ophthalmic vein. The inferior petrosal sinus was patent in one patient and thrombosed in four. Additional venous drainage into the Sylvian vein and the superior petrosal sinus was observed in two patients. FINDINGS: The definitive NBCA injection was performed via the branches of the middle meningeal artery in three patients and accessory meningeal artery as well as ascending pharyngeal artery in two patients. Four patients showed complete obliteration of the DCCF on the post-embolisation angiogram, and follow-up studies showed clinical cure or improvement and successful obliteration of the DCCF. One patient had a residual DCCF after the procedure, but showed complete obliteration and clinical cure at 5-month follow-up. Glue penetrated into the Sylvian vein in one patient during the procedure without sequelae. Two patients had transient worsening of ocular symptoms after the procedure. CONCLUSIONS: Trans-arterial embolisation with low concentration NBCA using a wedged microcatheter technique is still a safe and effective treatment for DCCF when the transvenous approach is not feasible. However, care must be taken to prevent inadvertent arterial and venous embolisation.

Reconstructive endovascular treatment of intracranial aneurysms with the Willis covered stent: medium-term clinical and angiographic follow-up.

OBJECT: Placement of covered stents has emerged as a promising therapeutic option for cerebrovascular diseases. However, the medium- and long-term efficacy and safety of covered stents in the treatment of these diseases remain unclear. The purpose of this study was to evaluate the medium-term clinical and angiographic outcomes of covered stent placement for the treatment of intracranial aneurysms. METHODS: The authors' institutional review board approved the study. Thirty-four patients (13 females and 21 males; mean age 41.9 years) with 38 intracranial aneurysms were treated with the Willis covered stent. Clinical and angiographic follow-up were performed at 3 months, at 6-12 months, and annually thereafter. The initial procedural and follow-up outcomes were collected and analyzed retrospectively. RESULTS: Forty-two covered stents were successfully implanted into the target artery in 33 patients with 37 aneurysms, and 1 covered stent navigation failed in 1 patient. A complete aneurysm exclusion was initially achieved in 24 patients with 28 aneurysms, and a minor endoleak occurred in 9 patients with 9 aneurysms. Postoperatively, 2 patients died of complications related to the procedure. Angiographic and clinical follow-up data are available in 30 patients. The angiographic follow-up (17.5 ± 9.4 months [mean ± SD]) exhibited complete occlusion in 28 patients with 31 aneurysms, and incomplete occlusion in 2 aneurysms, with an asymptomatic in-stent stenosis in 3 patients (10%). The clinical follow-up (26.7 ± 13 months [mean ± SD]) demonstrated that 16 patients (53.3%) experienced a full recovery, and 14 patients (46.7%) improved. No aneurysm rupture, thromboembolic events, or neurological deficits resulting from closure of a perforating vessel by covered stent placement occurred. CONCLUSIONS: Endovascular reconstruction with the Willis covered stent represents a safe, durable, and curative treatment option for selected intracranial aneurysms, yielding an excellent medium-term patency of the parent artery and excellent clinical outcomes.

[Experimental study on fabricating Ni-Cr alloy coping with laser rapid forming].

OBJECTIVE: To probe the feasibility of fabricating Ni-Cr alloy coping with laser rapid forming (LRF). METHODS: The digitalized model of coping was designed using the technology of reverse engineering and computer aided design (CAD) based on the abutment. The Ni-Cr alloy coping was fabricated with LRF. The gaps between the internal surface of coping and the external surface of abutment were measured respectively at the locations of occlusal surface edge, midpoint of axial wall and shoulder edge. The results were compared with the reference of 120 microm which was accepted generally to analyze the adaptation by statistical means. RESULTS: With statistical analysis of the t-test, the mean of gap width of each group, (82.60 +/- 13.58) microm for group A, (45.80 +/- 16.12) microm for group B, and (57.90 +/- 9.04) microm for group C, was less than 120 pm and the differences were statistically significant (t(A) = 8.71, t(B) = 14.56, t(C) =21.72, P <0.05). CONCLUSIONS: The Ni-Cr alloy coping with a thickness of 0.8 mm can be fabricated with LRF successfully and the adaptation can meet the reference of 120 microm.

Transferring complementary target DNA from aqueous solutions onto solid surfaces by using affinity microcontact printing.

In this paper, we report a method of transferring complementary target DNA from an aqueous solution onto a solid surface by using affinity microcontact printing. In this approach, the probe DNA is first immobilized on the surface of an aminated poly(dimethylsiloxane) (PDMS) stamp. After a complementary target DNA hybridizes with the probe DNA on the stamp surface, the PDMS stamp is printed on an aminated glass slide. By using fluorescent microscopy, we show that only complementary target DNA, but not noncomplementary DNA, can be captured onto the surface of the stamp and then transferred to the aminated glass slide. The transfer of DNA can be attributed to the stronger electrostatic attraction between DNA and amine groups compared to the hydrogen bonds between the hybridized DNA molecules. We also investigate several factors that may influence the transfer of DNA, such as the surface density of amine groups, hybridization conditions, and contamination from unreacted PDMS monomers.