Hydrophobic TaOx Species Overlayer Tuning Light-Driven Methane Chlorination with Inorganic Chlorine.

Halogenated methane serves as a universal platform molecule for building high-value chemicals. Utilizing sodium chloride solution for photocatalytic methane chlorination presents an environmentally friendly method for methane conversion. However, competing reactions in gas-solid-liquid systems leads to low efficiency and selectivity in photocatalytic methane chlorination. Here, an in situ method is employed to fabricate a hydrophobic layer of TaOx species on the surface of NaTaO3. Through in-situ XPS and XANES spectra analysis, it is determined that TaOx is a coordination unsaturated species. The TaOx species transforms the surface properties from the inherent hydrophilicity of NaTaO3 to the hydrophobicity of TaOx/NaTaO3, which enhances the accessibility of CH4 for adsorption and activation, and thus promotes the methane chlorination reaction within the gas-liquid-solid three-phase system. The optimized TaOx/NaTaO3 photocatalyst has a good durability for multiple cycles of methane chlorination reactions, yielding CH3Cl at a rate of 233 µmol g-1 h-1 with a selectivity of 83%. In contrast, pure NaTaO3 exhibits almost no activity toward CH3Cl formation, instead catalyzing the over-oxidation of CH4 into CO2. Notably, the activity of the optimized TaOx/NaTaO3 photocatalyst surpasses that of reported noble metal photocatalysts. This research offers an effective strategy for enhancing the selectivity of photocatalytic methane chlorination using inorganic chlorine ions.

Exploring BODIPY derivatives as sonosensitizers for anticancer sonodynamic therapy.

Sonodynamic therapy (SDT) is an emerging non-invasive and effective therapeutic modality for cancer treatment bearing benefit of deep tissue-penetration in comparison to photo-inspired therapy. However, exploring novel sonosensitizers with high sonosensitivity and desirable biosafety remains a significant challenge. Although boron dipyrromethene (BODIPY) dyes have been widely used in biomedical filed, no BODIPY-based sonosensitizers have been reported yet. Herein, we synthesized four BODIPY dyes (BDP1-BDP4) and investigated their potential applications in SDT. BDP4 exhibited superb sonosensitivity and high SDT efficiency against cancer cells and tumors in tumor-bearing mice. The types of the generated reactive oxygen species, cavitation effect, and cell apoptosis were investigated to figure out the sonodynamic therapeutic mechanisms of BDP4. This work for the first time demonstrates the potential of BODIPY dyes as novel sonosensitizers for SDT, which may pave an avenue for developing more efficient and safer sonosensitizers in future.

Three-pronged attacks by hybrid nanoassemblies involving a natural product, carbon dots, and Cu2+ for synergistic HCC therapy.

Tumor microenvironment (TME) stimuli-responsive nanoassemblies are emerging as promising drug delivery systems (DDSs), which acquire controlled release by structural transformation under exogenous stimulation. However, the design of smart stimuli-responsive nanoplatforms integrated with nanomaterials to achieve complete tumor ablation remains challenging. Therefore, it is of utmost importance to develop TME-based stimuli-responsive DDSs to enhance drug-targeted delivery and release at tumor sites. Herein, we proposed an appealing strategy to construct fluorescence-mediated TME stimulus-responsive nanoplatforms for synergistic cancer therapy by assembling photosensitizers (PSs) carbon dots (CDs), chemotherapeutic agent ursolic acid (UA), and copper ions (Cu2+). First, UA nanoparticles (UA NPs) were prepared by self-assembly of UA, then UA NPs were assembled with CDs via hydrogen bonding force to obtain UC NPs. After combining with Cu2+, the resulting particles (named UCCu2+ NPs) exhibited quenched fluorescence and photosensitization due to the aggregation of UC NPs. Upon entering the tumor tissue, the photodynamic therapy (PDT) and the fluorescence function of UCCu2+ were recovered in response to TME stimulation. The introduction of Cu2+ triggered the charge reversal of UCCu2+ NPs, thereby promoting lysosomal escape. Furthermore, Cu2+ resulted in additional chemodynamic therapy (CDT) capacity by reacting with hydrogen peroxide (H2O2) as well as by consuming glutathione (GSH) in cancer cells through a redox reaction, hence magnifying intracellular oxidative stress and enhancing the therapeutic efficacy due to reactive oxygen species (ROS) therapy. In summary, UCCu2+ NPs provided an unprecedented novel approach for improving the therapeutic efficacy through the three-pronged (chemotherapy, phototherapy, and heat-reinforced CDT) attacks to achieve synergistic therapy.

Rational design of a minimum nanoplatform for maximizing therapeutic potency: Three birds with one stone.

Therapeutic modalities and drug formulations play a crucial and prominent role in actualizing effective treatment and radical cures of tumors. However, the therapeutic efficiency was severely limited by tumor recurrence and complex multi-step preparation of formulation. Therefore, the exploration of novel nanoparticles via a simple and green synthesis process for conquering traditional obstacles and improving therapeutic efficiency is an appealing, yet remarkably challenging task. Herein, a universal nanoplatform allows all cancerous cell-targeting, acid-responsive, cell imaging, synergistic chemotherapy, and nucleolar targeted phototherapy function was tactfully designed and constructed by using chemotherapeutic agents ursolic acid (UA), sorafenib (SF), and carbon dots (CDs) photosensitizers (PSs). The designed US NPs were formed by self-assembly of UA and SF associated with electrostatic, π-π stacking, and hydrophobic interactions. After hydrogen bonding reaction with CDs, the obtained (denoted as USC NPs) have a relatively uniform size of an average 125.6 nm, which facilitated the favorable accumulation of drugs at the tumor region through a potential enhanced permeability and retention (EPR) effect as compared to their counterpart of free CDs solution. Both in vitro and in vivo studies revealed that the advanced platform commenced synergistic anticancer therapeutic potency, imperceptible systematical toxicity, and remarkable reticence towards drug-resistant cancer cells. Moreover, the CDs PSs possess intrinsic nucleolus-targeting ability. Taken together, this theranostics system can fully play the role of "killing three birds with one stone" in a safe manner, implying a promising direction for exploring treatment strategies for cancer and endowing them with great potential for future translational research and providing a new vision for the advancing of an exceptionally forceful protocol for practical cancer therapy.

Fabrication of 2H/3C-SiC heterophase junction nanocages for enhancing photocatalytic CO2 reduction.

The morphology and structure of photocatalyst play an important role in photocatalytic activity. SiC semiconductor is considered as a promising material for the photocatalytic CO2 reduction due to its negative conduction band position. Herein, SiC nanocages is creatively synthesized by simple low-temperature molten-salt-mediated magnesiothermic reduction method with using SiO2 as template. The morphology and phase composition of SiC nanocages can be controlled by magnesium dosage and reaction temperature. The 2H and 3C crystal phase in SiC nanocage can form heterophase junctions uniformly to effectively accelerate the photogenerated electron transfer, and plays a key role in improving the photocatalytic activity of 2H/3C-SiC samples. The optimal SiC nanocage sample possesses a CO generation rate of 4.68 µmol g-1h-1 for photocatalytic CO2 reduction, which is 3.25 times higher than that of commercial SiC.

[Medial approach versus lateral approach in laparoscopic colorectal resection: a meta-analysis].

OBJECTIVE: To compare the safety and efficacy of the medial approach(MA) and the lateral approach (LA) in the treatment of colorectal disease. METHODS: Studies published from January 1994 to April 2013 that compared MA to LA in laparoscopic colorectal resection were collected. Publications in English were mainly identified from Medline, Embase, Cochrane Library, and those in Chinese from Wanfang database and CNKI database. Conversion rate, operative time, blood loss, number of harvested lymph nodes, hospital stay, complication, mortality, recurrence, and hospitalization costs of MA and LA were meta-analyzed using fixed-effect and random-effect models. RESULTS: Five cohort studies (2 randomized controlled trials and 3 retrospective studies) including 881 patients were enrolled and analyzed. Of these patients, 416 and 465 underwent laparoscopic colorectal resection with MA and LA respectively. As compared to LA, MA had significantly lower conversion rate (OR=0.42, 95%CI:0.25-0.72, P=0.001), shorter operative time (WMD=-52.62, 95%CI:-63.23--42.01, P<0.01), less number of harvested lymph nodes (WMD=-1.17, 95%CI:-1.89--0.45, P=0.001), while blood loss was less and hospitalization cost lower. Significant differences in intraoperative complications and postoperative complications were not found between the two group (OR:0.57, 95%CI:0.15-2.18, P=0.41; OR:0.78, 95%CI:0.52-1.17, P=0.23). CONCLUSIONS: Compared with LA, MA has the advantages of shorter operative time and lower conversion rate with similar safety. Differences in blood loss, hospitalization cost and oncological safety between the two approaches warrant further investigation.

[Expression and significance of Slug, E-cadherin and N-cadherin in gastrointestinal stromal tumors].

OBJECTIVE: To explore the expression and clinical significance of Slug, E-cadherin and N-cadherin in gastrointestinal stromal tumors (GIST). METHODS: Seventy eight GIST specimens removed surgically from 2004 to 2007 were collected from the Department of Gastrointestinal Surgery at Guizhou Provincial People's Hospital. There were 48 males and 30 females with an age range of 28 - 87 years old. The expressions of Slug, E-cadherin and N-cadherin in GIST were determined by immunohistochemistry. And the correlations with their clinicopathologic characteristics were analyzed. RESULTS: The positive rates of Slug, E-cadherin and N-cadherin in GIST were 53.8% (42/78), 35.9% (28/78) and 75.6% (59/78) respectively. And the differences were statistically significant (χ(2) = 24.98, P < 0.05). Slug was expressed markedly higher in the cases of GIST with distant metastasis or distant metastasis and local invasion: 75% (18/24) vs 44.4% (24/54), 63.6% (28/44) vs 41.2% (14/34), both P < 0.05. And E-cadherin was expressed markedly lower in the cases of GIST with distant metastasis: 16.7% (4/24) vs 44.4% (24/54), P < 0.05. The expression of N-cadherin was not significantly different between its clinicopathological characteristics (allP > 0.05). The expression of Slug correlated negatively with that of E-cadherin (r(s) = -0.267, P = 0.018). But it had no correlation with that of N-cadherin (r(s) = 0.056, P = 0.625). CONCLUSION: Slug is expressed markedly higher while E-cadherin markedly lower in metastatic GIST, and both are closely correlated with the metastasis of GIST.

[Meta-analysis of laparoscopic and open repair of perforated peptic ulcer].

OBJECTIVE: To assess the safety and feasibility of laparoscopic and open repair of perforated peptic ulcer. METHODS: Studies on comparison between laparoscopic repair(LR) and open repair(OR) of perforated peptic ulcer were collected. Data of operating time, blood loss, time to first flatus, postoperative hospital stay, postoperative complications and mortality between LR group and OR group were meta-analyzed using fixed effect model and random effect model. RESULTS: Nineteen studies including 1507 patients were selected for this study,including laparoscopic surgery(n=673) and open surgery(n=834). There were significant differences in blood loss, time to first flatus, postoperative hospital stay, wound infection rate and mortality between LR group and OR group. However, no significant differences existed in operative time, postoperative sepsis, pulmonary infection, abdominal abscess, and suture leakage between the two groups. CONCLUSIONS: Laparoscopic repair of perforated peptic ulcer is associated with improved outcomes in terms of less blood loss, quicker recovery, and lower rates of wound infection and mortality. Laparoscopic repair of perforated peptic ulcer is safe and feasible.

[Necessity of splenectomy in radical resection of gastric cancer: a meta-analysis].

OBJECTIVE: To evaluate the necessity of splenectomy in radical resection of gastric cancer. METHODS: Twelve studies comparing outcomes after radical resection of gastric cancer with or without splenectomy were identified. Both fixed effect model and random effect model were used. RESULTS: There were 2628 patients in total. There were significant differences in complications between splenectomy group and spleen-preserving group(OR=1.91, 95% CI:1.28-2.87, P<0.05), while no significant difference in 5-year survival rate was noticed(HR=0.90, 95% CI:0.73-1.11, P>0.05). CONCLUSION: Radical resection of gastric cancer combined with splenectomy is not associated with improved survival but increased postoperative complications.