Diterpenes, an important class of natural compounds, are widely distributed in nature. As the valuable diterpenoids continue to be found, diterpene synthase in the course of diterpene synthesis get as much attention as possible. The multiformity of end-product-diterpenoids were also due to the diversity of diterpene synthase. This paper focuses on the advances in recent biosynthesis pathway of diterpene and types, cloning, catalytic mechanism, synthetic biology application.
Alkyl and Aryl Transferases ; metabolism ; Biosynthetic Pathways ; Diterpenes ; metabolism ; Isomerases ; metabolism ; Phosphorus-Oxygen Lyases ; metabolism ; Plant Proteins ; metabolism

OBJECTIVETo study the effect of Dangua Recipe (DGR) on glycolipid metabolism, vascular cell adhesion molecule-1 (VCAM-1) and its mRNA expression level of transgenic Apo E(-/-) mouse with spontaneous atherosclerosis, thus revealing its partial mechanism for curing diabetes mellitus (DM) with angiopathy.

METHODSDiabetic model was prepared by peritoneally injecting streptozotocin (STZ) to Apo E(-/-) mouse. Totally 32 modeled mice were stratified by body weight, and then divided into 4 groups referring to blood glucose levels from low to high by random digit table, i.e., the model group (MOD, fed with sterile water, at the daily dose of 15 mL/kg), the DGR group (fed with DGR at the daily dose of 15 mL/kg), the combination group (COM, fed with DGR at the daily dose of 15 mL/kg and pioglitazone at the daily dose of 4.3 mg/kg), and the pioglitazone group (PIO, at the daily dose of 4.3 mg/kg), 8 in each group. Another 8 normal glucose C57 mouse of the same age and strain were recruited as the control group. All interventions lasted for 12 weeks by gastrogavage. The fasting blood glucose (FBG), body weight, food intake, water intake, skin temperature, the length of tail, and the degree of fatty liver were monitored. The hemoglobin A1c (HbA1c), total cholesterol (TC), and LDL-C were determined. Endothelin-1 (ET-1) was determined by radioimmunoassay. Nitrogen monoxidum (NO) was determined by nitrate reductase. The kidney tissue VCAM-1 level was analyzed with ELISA. The expression of VCAM-1 mRNA in the kidney tissue was detected with real time quantitative PCR.

RESULTSCompared with the control group, the body weight and food intake decreased, water intake increased in all the other model groups (P < 0.05). Besides, the curve of blood glucose was higher in all the other model groups than in the control group (P < 0.01). Compared with the model group, the body weight increased; levels of HbAlc, TC, LDL-C, ET-1, and VCAM-1 were significantly lower; and skin temperature was higher in the DGR group (P < 0.05, P < 0.01). Compared with the PIO group, body weight, the increment of body weight, FBG, TC, and LDL-C were lower (P < 0.05, P < 0.01); food intake and water intake increased more and the tail length was longer in the DRG group (P < 0.01). There was no statistical difference in the level of NO among groups. The degree of fatty liver in the model group was significantly severer than that in the control group (P < 0.05). It was obviously alleviated in the DGR group (P < 0.05) when compared with the model group and the PIO group (P < 0.05, P < 0.01). But it was severer in the PIO group than in the model group (P < 0.01). The degree of fatty liver in the combination group ranged between that of the DGR group and the PIO group (P < 0.05). The level of VCAM-1 mRNA expression was significantly lower in the DGR group than in the model group, the PIO group, and the combination group (P < 0.05).

CONCLUSIONSDGR had effect in lowering blood glucose and blood lipids, and fighting against fatty liver of transgenic Apo E(-/-) mouse with spontaneous atherosclerosis. DGR played an effective role in preventing and treating DM with angiopathy by comprehensively regulating glycolipid metabolism and promoting the vascular function.

Animals ; Apolipoproteins E ; genetics ; Blood Glucose ; metabolism ; Diabetes Mellitus, Experimental ; blood ; drug therapy ; Diabetic Angiopathies ; drug therapy ; Drugs, Chinese Herbal ; pharmacology ; Lipids ; blood ; Male ; Mice ; Mice, Knockout ; RNA, Messenger ; genetics ; Random Allocation ; Thiazolidinediones ; pharmacology ; Vascular Cell Adhesion Molecule-1 ; genetics ; metabolism

Objectives: . Type 2 diabetes mellitus (T2DM) is a risk factor for deep neck infection (DNI) and leads to complications and poor outcomes. Our study aimed to investigate the risk, prognosis, and complications of peritonsillar abscess (PTA) in patients with T2DM. Methods: . We extracted data of patients newly diagnosed as having T2DM between January 2000 and December 2011 from Taiwan’s National Health Insurance Research Database. These patients were matched with patients without T2DM, and PTA incidence was compared between both cohorts. Results: . In total, 67,852 patients with and 135,704 patients without T2DM were enrolled. PTA incidence was significantly higher in patients with T2DM (incidence rate ratio, 1.91; P<0.001); moreover, PTA incidence was higher at 1 to 5 years after T2DM diagnosis than at <1 and >5 years after T2DM diagnosis. Cox regression analysis showed that patients with T2DM had an approximately 2-fold higher PTA risk (adjusted hazard ratio [aHR]: 1.89, P<0.001). Patients with a higher adapted Diabetes Complications Severity Index (aDCSI) had higher PTA risk than those with a lower aDCSI (aHRs: 2.17 for aDCSI ≥1, P=0.006 and 1.81 for aDCSI=0, P=0.002). T2DM patients with a high aDCSI (≥1) had a nonsignificantly longer hospitalization duration and a higher rate of DNI complications than did those with a low aDCSI (=0). Conclusion . In patients with T2DM, PTA incidence was relatively high, and it increased with T2DM severity. Moreover, T2DM patients should be particularly careful about PTA within 1 to 5 years after the diagnosis, and physicians should keep in mind that the prognosis of PTA was correlated with T2DM severity.

Objectives: . Type 2 diabetes mellitus (T2DM) is a risk factor for deep neck infection (DNI) and leads to complications and poor outcomes. Our study aimed to investigate the risk, prognosis, and complications of peritonsillar abscess (PTA) in patients with T2DM. Methods: . We extracted data of patients newly diagnosed as having T2DM between January 2000 and December 2011 from Taiwan’s National Health Insurance Research Database. These patients were matched with patients without T2DM, and PTA incidence was compared between both cohorts. Results: . In total, 67,852 patients with and 135,704 patients without T2DM were enrolled. PTA incidence was significantly higher in patients with T2DM (incidence rate ratio, 1.91; P<0.001); moreover, PTA incidence was higher at 1 to 5 years after T2DM diagnosis than at <1 and >5 years after T2DM diagnosis. Cox regression analysis showed that patients with T2DM had an approximately 2-fold higher PTA risk (adjusted hazard ratio [aHR]: 1.89, P<0.001). Patients with a higher adapted Diabetes Complications Severity Index (aDCSI) had higher PTA risk than those with a lower aDCSI (aHRs: 2.17 for aDCSI ≥1, P=0.006 and 1.81 for aDCSI=0, P=0.002). T2DM patients with a high aDCSI (≥1) had a nonsignificantly longer hospitalization duration and a higher rate of DNI complications than did those with a low aDCSI (=0). Conclusion . In patients with T2DM, PTA incidence was relatively high, and it increased with T2DM severity. Moreover, T2DM patients should be particularly careful about PTA within 1 to 5 years after the diagnosis, and physicians should keep in mind that the prognosis of PTA was correlated with T2DM severity.

INTRODUCTIONThis study investigated whether heavy metal levels were higher in people from Taiwan as compared to those from Western countries.

METHODSWe measured the level of heavy metals (lead, mercury, arsenic and cadmium) in the blood of 40 apparently healthy adults. Since mercury does not respond to ethylenediaminetetraacetic acid (EDTA) infusion, only urine lead, arsenic and cadmium levels were determined by applying the body burden concept after calcium disodium EDTA infusion. These three heavy metals were extracted from daily urine samples for three consecutive days.

RESULTSThe mean blood lead, mercury and cadmium levels of the Taiwanese individuals (24.46 ± 9.69 µg/L, 9.64 ± 6.98 µg/L and 0.73 ± 0.27 µg/L, respectively) were greater than those of the Americans. The Taiwanese also had greater blood mercury and cadmium levels than the Germans. The first-day urine lead, arsenic and cadmium levels were 77.9%, 33.1% and 62.4%, respectively, of the total lead, arsenic and cadmium excretion during the three days. This indicates that the first-day urine lead and cadmium excretion represented most (> 60%) of the lead and cadmium excretion in those three days.

CONCLUSIONThis study demonstrated that the Taiwanese population has higher blood mercury and cadmium levels than Western populations. To study the urine lead and cadmium body burden of patients, detection of first-day, rather than three-day, urine lead and cadmium levels can be done, as the former yields results that are fairly representative, and is more time- and cost-effective.

Background/Aims: Despite the high efficacy of direct-acting antivirals (DAAs), approximately 1–3% of hepatitis C virus (HCV) patients fail to achieve a sustained virological response. We conducted a nationwide study to investigate risk factors associated with DAA treatment failure. Machine-learning algorithms have been applied to discriminate subjects who may fail to respond to DAA therapy. Methods: We analyzed the Taiwan HCV Registry Program database to explore predictors of DAA failure in HCV patients. Fifty-five host and virological features were assessed using multivariate logistic regression, decision tree, random forest, eXtreme Gradient Boosting (XGBoost), and artificial neural network. The primary outcome was undetectable HCV RNA at 12 weeks after the end of treatment. Results: The training (n=23,955) and validation (n=10,346) datasets had similar baseline demographics, with an overall DAA failure rate of 1.6% (n=538). Multivariate logistic regression analysis revealed that liver cirrhosis, hepatocellular carcinoma, poor DAA adherence, and higher hemoglobin A1c were significantly associated with virological failure. XGBoost outperformed the other algorithms and logistic regression models, with an area under the receiver operating characteristic curve of 1.000 in the training dataset and 0.803 in the validation dataset. The top five predictors of treatment failure were HCV RNA, body mass index, α-fetoprotein, platelets, and FIB-4 index. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of the XGBoost model (cutoff value=0.5) were 99.5%, 69.7%, 99.9%, 97.4%, and 99.5%, respectively, for the entire dataset. Conclusions Machine learning algorithms effectively provide risk stratification for DAA failure and additional information on the factors associated with DAA failure.