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Steel baffle installed on footing is commonly used to resist and dissipate the impact energy from boulders carried by debris flow. However, the deformation of a baffle and the resulting energy transfer to the footing during the impact process compound the challenges of predicting the impact force and size of the footing required. In this study, full-scale experiments were conducted to simulate a boulder impacting a steel baffle installed on a square footing. The experimental data were back-analyzed using a three-dimensional (3D) finite element model, which was then used to conduct a parametric study to examine the effects of a range of impact energies and footing sizes. New design charts are developed to assess the required size of a square footing, embedded up to 2 m depth, for a steel baffle subjected to boulder impact with energy in the range of 10–100 kJ.

Phosphorus (P) deficiency in agricultural soil is a worldwide concern. P modification of biochar, a common soil conditioner produced by pyrolysis of wastes and residues, can increase P availability and improve soil quality. This study aims to investigate the effects of P-modified biochar as a soil amendment on the growth and quality of a medicinal plant (Pseudostellaria heterophylla). P. heterophylla were grown for 4 months in lateritic soil amended with P-modified and unmodified biochar (peanut shell) at dosages of 0, 3% and 5% (by mass). Compared with unmodified biochar, P-modified biochar reduced available heavy metal Cd in soil by up to 73.0% and osmotic suction in the root zone by up to 49.3%. P-modified biochar application at 3% and 5% promoted the tuber yield of P. heterophylla significantly by 68.6% and 136.0% respectively. This was different from that in unmodified biochar treatment, where tuber yield was stimulated at 3% dosage but inhibited at 5% dosage. The concentrations of active ingredients (i.e., polysaccharides, saponins) in tuber were increased by 2.9–78.8% under P-modified biochar amendment compared with control, indicating the better tuber quality. This study recommended the application of 5% P-modified biochar for promoting the yield and quality of P. heterophylla.

Over the past few decades, high-throughput screening (HTS) has made great contributions to new drug discovery. HTS technology is equipped with higher throughput, minimized platforms, more automated and computerized operating systems, more efficient and sensitive detection devices, and rapid data processing systems. At the same time

Four novel betulinic acid (BA) derivatives modified at the C-3 position were prepared by the Mitsunobu reaction and subsequently evaluated for antitumor activity against four common cancer cell lines in vitro. The results from the MTT assay revealed that the four tested compounds showed remarkable cytotoxic activity against four cancer cell lines, much better than BA. Western blotting results indicated that the four compounds, especially compound 2c, caused a significant up-regulation expression of the caspase-12 in CT26 cell. Our results showed that configuration inversions of chiral C-3 of BA could also produce BA derivatives with potent antitumor activity.

Chlorogenic acid (CGA) has been reported to exhibit potent anti-inflammatory activity. However, the development of anti-inflammatory agent based on CGA has not been investigated. In this paper, a series of caffeoyl salicylate compounds derived from CGA were designed, synthesized, and evaluated by LPS-induced nitric oxide synthase inhibition and QRT-PCR technique. Most compounds showed modest activity to inhibit production of nitric oxide (NO) in RAW 264.7 cells induced by lipopolysaccharides (LPS). Among these compounds, QRT-PCR and western blotting results indicated that compounds 6b, 6c, 6f, 6g and D104 that possess 5-member ring or 6-member ring caused a significant inhibition against expression of the iNOS2 in LPS-induced macrophages. In addition, cytotoxic assay displayed most derivatives have good safety in vitro. This new promising scaffold could be further exploited for the development of anti-inflammatory agent in the future.

Berberine (BBR), isolated from a Chinese herb, is identified as a new cholesterol-lowering small molecule, and hundreds of berberine derivatives have been obtained for optimization of their hypolipidemic activities in recent years. However, so far there is no available quantitative structure-activity relationship (QSAR) model used for the development of novel BBR analogues with hypolipidemic activities, mainly due to lack of lipid-lowering molecular mechanisms and target identification of BBR. In this paper, the tactics using ligand efficiency indice instead of pIC50 as the activity could be adopted for the development of BBR QSAR models. A series of 59 BBR derivatives with hypolipidemic activities have been studied and split randomly into three sets of training and test sets. Statistical quality of most building models shows obviously robust. Best calculated model that employs LLE indice as the activity (Model 6) has the following statistical parameters: for training set R2 = .984, Q2 = 0.981, RMSE = 0.1160, and for test set R2 = .989, RMSE = 0.0067. This model would be used for the development of novel BBR analogues with lipid-lowering activities as a hit discovery tool.

Desmoid tumors (DTs) are nonmetastatic, locally aggressive neoplasms with a high rate of postoperative recurrence. Pancreatic DTs are especially rare; only a few cases have been reported to date. This paper describes a case of a sporadic cystic DT of the pancreas managed successfully with central pancreatectomy, with no signs of recurrence 40 mo after surgery. According to the literature, this is the first reported case in China of a pancreatic DT presenting as a solid cystic lesion, as well as the first pancreatic DT managed with central pancreatectomy and pancreaticogastrostomy. We report the case for its rarity and emphasize disease management by concerted application of clinical, pathological, radiological and immunohistochemical analyses.

During the past decade, laparoscopic distal pancreatectomy (LDP) has gained increasing acceptance in the surgical community as a viable treatment option for distal pancreatic lesions. However, the possible complication of post-LDP pancreatic leakage remains a challenge, because it may lead to a series of events resulting in intraperitoneal abscess formation, sepsis, pseudoaneurysm formation, and occasional fatal hemorrhage. Dealing with these complications is extremely difficult and not much experience has been reported to date. We report a case involving the aforementioned post-LDP complications successfully managed by interventional radiological techniques while avoiding reoperation. We conclude that these management options are attractive, safe and minimally invasive alternatives to standard protocols.

Isolated metastases to the spleen from gastric carcinoma is very rare. Only a few cases have been reported in the literature. We herein present a case of isolated splenic metastases in a 62-year-old man, occurring 12 mo after total gastrectomy for gastric carcinoma. The patient underwent a laparoscopic exploration, during which two lesions were found at the upper pole of the spleen, without involvement of other organs. A laparoscopic splenectomy was performed. Histological examination confirmed that the splenic tumor was a poorly differentiated adenocarcinoma similar to the primary gastric lesion. The postoperative course was uneventful and the patient has been well for 9 mo, with no tumor recurrence. The clinical data of 18 cases of isolated splenic metastases from gastric carcinoma treated by splenectomy were summarized after a literature review. To our knowledge, this is the first reported case of isolated splenic metastases undergoing laparoscopic splenectomy.

To evaluate the feasibility and efficacy of laparoscopic distal pancreatectomy.Totally 68 patients (male 23, female 45) aged 17 to 77 years, with distal pancreatic lesions, underwent laparoscopic distal pancreatectomy from November 2003 to December 2010. The clinical data were collected. Safety, feasibility and crucial technique manipulation were analyzed retrospectively.All 68 operations were successful with two cases conversion to open, including 48 cases combined with splenectomy, and 18 cases with preservation of spleen. Fourteen cases received with combination resection of multi-organs, including 4 cases with cholecystectomy, 1 case resection of right adrenal adenoma and cholecystectomy, 1 case with myomectomy and left ovarian teratomectomy; 1 case with right ovarian teratomectomy, 1 case with resection of left adrenal adenoma, 1 case with resection of both adrenal adenoma, 1 case with resection of liver metastasis, 1 case with cholecystectomy and resection of liver metastasis, 1 case with resection of left adrenal adenoma and liver metastasis, 1 case with resection of left adrenal adenoma and colon and spleen, 1 case with biopsy of liver nodule. The mean operative time was (209 ± 58) minutes, the mean intraoperative blood loss was (191 ± 123) ml, and the mean postoperative hospital stay was (8 ± 4) days. The rate of overall postoperative complications was 18.1%, including an 12.1% rate of clinical pancreatic fistula. Only one case needed a reoperation, and there was no postoperative mortality.Laparoscopic distal pancreatectomy with or without splenectomy is safe and feasible in the treatment of most distal pancreatic tumors.