Two new daphnane diterpenes from the roots of Stelleropsis tianschanica.

Two new daphnane diterpenes named tianchaterpenes A and B were isolated from the roots of Stelleropsis tianschanica. Their structures were elucidated on the basis of chemical and spectral analysis, including 1D, 2D NMR analyses and HRESIMS. Compounds 1 and 2 were evaluated for their cytotoxic activities against HeLa and HCT-8 cell lines. The results showed that all compounds displayed weak cytotoxicities to the HeLa cells and were inactive to the HCT-8 cells.

Asymmetric Darzens Reaction of Isatins with Diazoacetamides Catalyzed by Chiral BINOL-Titanium Complex.

An efficient catalytic asymmetric Darzens reaction of N-protected isatins with diazoacetamides using a chiral BINOL/Ti(OiPr)4 complex as the catalyst has been developed. This reaction is a straightforward method for the synthesis of spiro-epoxyoxindoles in 40-95% yields, up to >20:1 dr and up to >99% ee. A gram-scale reaction was also achieved in 95% yield with excellent stereoselectivity and enantioselectivity (>20:1 dr, >99% ee).

Our expedition in eight-membered ring compounds: from planar dehydrocyclooctenes to tub-shaped chiral tetraphenylenes.

Our research focus for almost forty years concerning eight-membered ring compounds is herein summarized. The design and preparation of these structurally unique compounds featuring a central cyclooctene ring are described in the context of their planar or tub-shaped conformations. Furthermore, their intrinsic properties and potential applications are also presented.

Asymmetric synthesis of 3,3,5,5-tetrasubstituted 1,2-dioxolanes: total synthesis of epiplakinic acid F.

The first enantioselective total synthesis of epiplakinic acid F (1) was achieved through a pivotal step involving a radical-mediated asymmetric peroxidation of vinylcyclopropanes with molecular oxygen to construct highly substituted 1,2-dioxolanes. Subsequent conversions of the chiral 1,2-dioxolanes led to total synthesis of epiplakinic acid F (1) and the confirmation of its absolute configuration. The enantiomer of epiplakinic acid F methyl ester (2) was also prepared.

Spontaneous coronary artery rupture after lung cancer surgery: A case report and review of literature.

BACKGROUND: Spontaneous coronary artery rupture (SCAR) is a rare and life-threatening complication after lung cancer surgery. We present a case of SCAR following left upper lobectomy, successfully managed through emergency thoracotomy and coronary artery ligation. CASE SUMMARY: A 61-year-old male patient underwent left upper lobectomy and mediastinal lymph node dissection for lung cancer. The surgery was performed using single-port video-assisted thoracoscopic surgery, and there were no observed complications during the procedure. However, 19 h after surgery, the patient experienced chest discomfort and subsequently developed severe symptoms, including nausea, vomiting, and a drop in blood pressure. Urgent measures were taken, leading to the diagnosis of SCAR. The patient underwent emergency thoracotomy and coronary artery ligation, successfully stopping the bleeding and stabilizing the condition. Despite postoperative complications, the patient made a successful recovery and was discharged from the hospital. CONCLUSION: SCAR is a rare but life-threatening complication following lung cancer surgery. Immediate thoracotomy has been shown to be a life-saving measure, while stenting is not the preferred initial approach.

Fe@χ3-borophene as a promising catalyst for CO oxidation reaction: A first-principles study.

A novel single-atom catalyst of Fe adsorbed on χ3-borophene has been proposed as a potential catalyst for CO oxidation reaction (COOR). Quantitative pictures have been provided of both the stability of Fe@χ3-borophene and various kinetic reaction pathways using first-principles calculations. Strong adsorption energy of -3.19 eV and large diffusion potential of 3.51 eV indicates that Fe@χ3-borophene is highly stable. By exploring reaction mechanisms for COOR, both Eley-Ridel (E-R) and trimolecule E-R (TER) were identified as possible reaction paths. Low reaction barriers with 0.49 eV of E-R and 0.57 eV of TER suggest that Fe@χ3-borophene is a very promising catalyst for COOR. Charge transfer between the χ3-borophene and CO, O2 and CO2 gas molecules plays a key role in lowering the energy barrier during the reactions. Our results propose that Fe@χ3-borophene can be a good candidate of single-atom catalyst for COOR with both high stability and catalytic activity.

[Nedaplatin combined with tegafur in the treatment for advanced esophageal cancer].

OBJECTIVE: To investigate the efficacy and toxicity of nedaplatin combined with tegafur in the treatment for patients with advanced esophageal cancer. METHODS: Among the 65 patients with advanced esophageal cancer, 27 had no history of prior chemotherapy and the other 38 had ever received postoperative adjuvant chemotherapy before. The median age of those cases was 58.0 years. Nedaplatin was given daily by intravenous infusion at a dose of 20 mg/m(2) for 2 hours and tegafur at a dose of 500 mg/m(2) for 8 hours on D1 approximately D5, every 21 days as a cycle. RESULTS: 193 cycles of chemotherapy were accomplished in the 65 patients, and 63 patients were evaluable for response evaluation. Of 27 patients with no prior history of chemotherapy, 6 achieved complete response and 16 partial response, with a response rate (CR + PR) of 81.5%. Among the 36 patients who had ever received postoperative adjuvant chemotherapy, 6 obtained complete response and 10 partial response with a response rate (CR + PR) of 44.4%. The overall median time to tumor progression in this series was 5.6 months. The overall median actuarial survival was 9.3 months, and the one-year survival rate was 24.9%. Nausea and vomiting were the major toxicities, but were mild and well tolerable. Grade 3 to 4 neutropenia was only observed in two patients (3.2%). CONCLUSION: The regimen of nedaplatin combined with tegafur is effective and tolerable for the treatment of advanced esophageal cancer.

Synthesis and Chiroptical Properties of Double-Helical (M)- and (P)-o-Oligophenylenes.

All of the M and P isomers of optically pure oligophenylenes with 6, 8, 10, and 12 phenyl rings were synthesized and fully characterized. The Suzuki cross-coupling reaction has been revealed to be a viable strategy in the syntheses of tetraphenylene derivatives, which, together with the copper-mediated oxidative cross-coupling reaction, were employed in the quest for the oligophenylenes. X-ray diffraction analysis in combination with specific rotation and circular dichroism spectroscopy unambiguously identified the unique covalent double-helical frameworks of these oligophenylene molecules.

[An improved liquid nitrogen freezing method for establishing canine models of femoral head necrosis].

OBJECTIVE: To establish an canine model of femoral head osteonecrosis using an improved liquid nitrogen freezing method. METHODS: Sixteen adult canines were divided into 4 groups at random and subjected to instant freezing of the unilateral femoral head with liquid nitrogen. The dogs were observed at 2, 4, 8, and 16 weeks after the operation for radiographic, gross and pathological changes of the femoral head. RESULTS: Significant radiographic, gross and pathological changes occurred in the femoral head after the freezing. CONCLUSION: Improved liquid nitrogen freezing of the femoral head provides a simple and convenient method for establishing animal models of femoral head osteonecrosis.

[Cloning and identification of microRNA from human osteosarcoma cell line SOSP-9607].

BACKGROUND & OBJECTIVE: MicroRNA (miRNA), a group of non-coding small RNA (20-25 nt) involved in post-transcriptional regulation, regulate gene expression and closely relate to cancer pathogenesis. This study was to clone miRNA from osteosarcoma cell line SOSP-9607, and identify the expression of some functional genes. METHODS: Low molecular weight RNA fraction (< or =200 nt) was extracted from SOSP-9607 cells, and polyadenylated by poly(A) polymerase. Then a 5' RNA adapter was ligated to poly(A)-tailed RNA using T4 RNA ligase. RNAs were reversely transcribed and amplified by reverse transcription-polymerase chain reaction (RT-PCR). The PCR product of 109 bp was recovered and cloned into pCR 4-TOPO vector. After sequencing, database searching, and expression profiling, the expression of miRNA in SOSP-9607 cells was sieved. The expression of novel and some known miRNAs was examined by Northern blot with small RNAs (< or =200 nt) isolated from SOSP-9607 cells, osteosarcoma tissue, and HeLa cells. RESULTS: A total of 182 clones were subsequently characterized through DNA sequencing and database searching; 47 clones (correspond to 25 species) out of the 182 clones from SOSP-9607 cells were identified as miRNAs. Two novel miRNAs (miR-165 and miR-166) were discovered among other 23 known miRNAs, which were predicted in Nature. Northern blot confirmed that the 2 novel miRNAs and 3 solid cancer miRNAs (miR-21, miR-20a,miR-17-5p) were stably expressed in SOSP-9607 cells and osteosarcoma tissue, but miR-166 was not expressed in HeLa cells. CONCLUSION: We have cloned miRNAs for SOSP-9607 cells and identified parts of the functional ones, which imply that miRNAs may closely relate to the cancer pathogenesis.