ABSTRACT
A new prenylated coumarin (1) and a new anthranilamide derivative (2) were isolated from the aerial parts of Evodia lepta. Compound 2 represents the first anthranilamide derivative from the Evodia genus. Their structures were elucidated by spectroscopic data analysis (MS, UV, IR, and NMR). Compound 1 exhibited certain inhibition on nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 macrophages with an IC50 value of 37.96 ± 1.7 µM.
Subject(s)
Evodia , Rutaceae , Coumarins , Lipopolysaccharides , Molecular Structure , Nitric Oxide , ortho-AminobenzoatesABSTRACT
Two new naphthoate derivatives, including a symmetrical dimer (1) and a monomer (2), were separated from the roots of Morinda officinalis var. hirsuta. Their structures were characterized on the basis of spectroscopic means especially MS and NMR methods. Biological evaluations revealed that the two compounds did not show inhibition against both cholinesterases AChE and BChE, while the dimer (1) did exhibit moderate growth inhibitory activity toward one human osteosarcoma cell line U2OS with an IC50 value of 18.5 ± 1.1 µM.
Subject(s)
Morinda , Rubiaceae , Acetylcholinesterase , Cholinesterase Inhibitors/pharmacology , Humans , Molecular Structure , Plant RootsABSTRACT
An oxidative [3 + 2] C-H spiroannulation reaction of 2-alkenylphenols with ynamides has been developed toward the synthesis of spiro[4,5]decane derivatives. This dearomative reaction employs earth-abundant cobalt as the metal catalyst and occurs under rather mild reaction conditions (room temperature). The use of ynamides confers unique reactivity and exclusive regioselectivity. The products bearing an all-carbon quaternary stereogenic center were constructed in generally good yields with good functional group tolerance being observed. Experimental mechanistic studies were conducted, and a possible reaction mechanism is proposed.
ABSTRACT
OBJECTIVE: To assess bone volume stability and identify critical bone graft thickness for guided bone regeneration (GBR) simultaneous to implant placement in the maxillary anterior region. METHODS: Eighteen patients were included in the study and received placement of one maxillary anterior implant combined with GBR using deproteinised bovine bone mineral (DBBM) and resorbable collagen membrane. The multilevel buccal bone thickness (BT) was measured by CBCT 1 to 2 weeks and 5 to 8 months post-implantation (at implant uncovering surgery). RESULTS: Significant buccal alveolar crest collapse (ACCb 1.20 to 1.70 mm) occurred during the mean healing period of 5.3 months (P = 0.000). A greater percentage of ACCb occurred at the coronal aspect of the implant, with 59.24% ± 19.22% at the implant platform and 34.10% ± 30.50% 6.0 mm below the implant platform, respectively. Linear regression analysis demonstrated that if BT was 1.8 to 2.0 mm at the implant platform at uncovering surgery, then it was estimated to have been 4.1 to 4.5 mm immediately post-implantation. CONCLUSION: ACCb after maxillary anterior implant placement with simultaneous GBR occurred more coronally than apically. Excessive alveolar ridge augmentation, up to 4.0 mm of hard tissue buccal to the implant platform, should be achieved at the time of surgery to compensate for this potential resorption.
Subject(s)
Alveolar Ridge Augmentation , Dental Implants , Animals , Bone Regeneration , Cattle , Dental Implantation, Endosseous , Humans , Maxilla/diagnostic imaging , Maxilla/surgeryABSTRACT
Phytochemical investigation of Croton crassifolius led to the isolation of two new halimane diterpenoids (1 and 2), a new nor-clerodane diterpenoid (3), along with three known analogues (4-6). Their structures including absolute configurations were elucidated by spectroscopic analysis, single-crystal X-ray diffraction, and CD analysis. All isolates were evaluated for their inhibitory effects on the nitric oxide (NO) production induced by lipopolysaccharide (LPS) in RAW264.7 macrophage cells, and compound 1 exhibited moderate inhibition of NO production with an IC50 value of 25.8 ± 0.9 µM.
Subject(s)
Croton/chemistry , Diterpenes/isolation & purification , Animals , Crystallography, X-Ray , Diterpenes/chemistry , Diterpenes/pharmacology , Diterpenes, Clerodane/chemistry , Diterpenes, Clerodane/isolation & purification , Inhibitory Concentration 50 , Lipopolysaccharides/pharmacology , Macrophages/drug effects , Macrophages/metabolism , Mice , Nitric Oxide/biosynthesis , Plant Roots/chemistry , RAW 264.7 CellsABSTRACT
OBJECTIVE: Hemorrhagic fever with renal syndrome (HFRS), one of the main public health concerns in mainland China, is a group of clinically similar diseases caused by hantaviruses. Statistical approaches have always been leveraged to forecast the future incidence rates of certain infectious diseases to effectively control their prevalence and outbreak potential. Compared to the use of one base model, model stacking can often produce better forecasting results. In this study, we fitted the monthly reported cases of HFRS in mainland China with a model stacking approach and compared its forecasting performance with those of five base models. METHOD: We fitted the monthly reported cases of HFRS ranging from January 2004 to June 2019 in mainland China with an autoregressive integrated moving average (ARIMA) model; the Holt-Winter (HW) method, seasonal decomposition of the time series by LOESS (STL); a neural network autoregressive (NNAR) model; and an exponential smoothing state space model with a Box-Cox transformation; ARMA errors; and trend and seasonal components (TBATS), and we combined the forecasting results with the inverse rank approach. The forecasting performance was estimated based on several accuracy criteria for model prediction, including the mean absolute percentage error (MAPE), root-mean-squared error (RMSE) and mean absolute error (MAE). RESULT: There was a slight downward trend and obvious seasonal periodicity inherent in the time series data for HFRS in mainland China. The model stacking method was selected as the best approach with the best performance in terms of both fitting (RMSE 128.19, MAE 85.63, MAPE 8.18) and prediction (RMSE 151.86, MAE 118.28, MAPE 13.16). CONCLUSION: The results showed that model stacking by using the optimal mean forecasting weight of the five abovementioned models achieved the best performance in terms of predicting HFRS one year into the future. This study has corroborated the conclusion that model stacking is an easy way to enhance prediction accuracy when modeling HFRS.
Subject(s)
Disease Outbreaks/statistics & numerical data , Epidemiological Monitoring , Hemorrhagic Fever with Renal Syndrome/epidemiology , Machine Learning , Neural Networks, Computer , China/epidemiology , Datasets as Topic , Forecasting/methods , Orthohantavirus/pathogenicity , Hemorrhagic Fever with Renal Syndrome/virology , Humans , Incidence , Models, Statistical , SeasonsABSTRACT
OBJECTIVES: Human brucellosis is a public health problem endangering health and property in China. Predicting the trend and the seasonality of human brucellosis is of great significance for its prevention. In this study, a comparison between the autoregressive integrated moving average (ARIMA) model and the eXtreme Gradient Boosting (XGBoost) model was conducted to determine which was more suitable for predicting the occurrence of brucellosis in mainland China. DESIGN: Time-series study. SETTING: Mainland China. METHODS: Data on human brucellosis in mainland China were provided by the National Health and Family Planning Commission of China. The data were divided into a training set and a test set. The training set was composed of the monthly incidence of human brucellosis in mainland China from January 2008 to June 2018, and the test set was composed of the monthly incidence from July 2018 to June 2019. The mean absolute error (MAE), root mean square error (RMSE) and mean absolute percentage error (MAPE) were used to evaluate the effects of model fitting and prediction. RESULTS: The number of human brucellosis patients in mainland China increased from 30 002 in 2008 to 40 328 in 2018. There was an increasing trend and obvious seasonal distribution in the original time series. For the training set, the MAE, RSME and MAPE of the ARIMA(0,1,1)×(0,1,1)12 model were 338.867, 450.223 and 10.323, respectively, and the MAE, RSME and MAPE of the XGBoost model were 189.332, 262.458 and 4.475, respectively. For the test set, the MAE, RSME and MAPE of the ARIMA(0,1,1)×(0,1,1)12 model were 529.406, 586.059 and 17.676, respectively, and the MAE, RSME and MAPE of the XGBoost model were 249.307, 280.645 and 7.643, respectively. CONCLUSIONS: The performance of the XGBoost model was better than that of the ARIMA model. The XGBoost model is more suitable for prediction cases of human brucellosis in mainland China.
Subject(s)
Brucellosis , Brucellosis/epidemiology , China/epidemiology , Humans , Incidence , Models, Statistical , SeasonsABSTRACT
OBJECTIVE: To investigate the indications, safety and difficulties of one stage thyroidectomy and bilateral neck lymph node dissection for well-differentiated thyroid carcinoma. METHODS: A retrospective review was carried out in 36 well-differentiated thyroid carcinoma patients so treated from 1990 to 2004. Various incisions including H, L and modified Kocher types were selected according to the location of primary tumor and status of cervical lymph node metastasis. Either total thyroidectomy or sub-total thyroidectomy combined with bilateral neck lymph node dissection according to the principles of modified radical neck lymph node dissection: preserving the internal jugular vein, spinal accessory nerve and sternocleidomastoid muscles. RESULTS: There was no operative death in this group. Postoperative complications included: 2 wound bleeding, 3 recurrent laryngeal nerve resection due to tumor involvement, 1 recurrent laryngeal nerve injury, 2 unilateral internal branch of superior laryngeal nerve injury, 9 unilateral external branch of superior laryngeal nerve injury, 3 unilateral accessory nerve injury, 5 unilateral sympathetic nerve injury, 2 unilateral phrenic nerve injury, 6 chylus fistula, 13 temporary hypoparathyroidism, 2 permanent hypoparathyroidism. The dissected lymph nodes were found to be positive from 0 to 21 in each patient with a mean of 8.3. Of the 36 patients: 31 had bilateral positive lymph nodes; 3 unilateral positive; 2 bilateral negative lymph nodes. The follow up period ranged from 1 to 13 years, Three patients died of distant metastasis, 1 died of cerebral vascular accident. 7 patients lost in follow-up. Totally, 25 patients are still alive, 3 patients had local relapse and were surgically treated again. CONCLUSION: The procedure of one-stage thyroidectomy and bilateral neck lymph node dissection for well-differentiated thyroid carcinoma is safe, as it is mandatory that at least one unilateral internal jugular vein should be preserved; one unilateral recurrent laryngeal nerves and accessory nerves should not be injured. Well-differentiated thyroid carcinoma patients whose bilateral cervical lymph nodes are clinically suspected to be positive (obviously enlarged, hard, purplish grapelike lymph node) or are confirmed pathologically to be positive are indications for one-stage thyroidectomy and bilateral neck lymph node dissection. Total or sub-total thyroidectomy should be undertaken with emphasis that at least one parathyroid with blood supply should be preserved. It is of utmost importance that not only the cancer be completely resected but the function of the organs be preserved.