Objective To investigate the indications to use a temporary pacemaker for bifascicular block in perioperative period.Methods The treatment for 40 patients with heart bifascicular block and a special case were retrospectively studied.All cases,according to their disease history,clinical symptoms,physical ability and atrio-ventricular conduction ability,were divided into two groups:P group(prophylactic insertion of a temporary pacemaker) and N group(without inserting a pacemaker).During operation,we observed whether atrio-ventricular block occurs,the performance of pacemaker and atropine's therapeutic efficacy to bradycardia.Results Anesthesia was postponed in one case because of acute left bundle branch block(LBBB) and the patient died with severe myocardium damage soon after failed resuscitation.All other cases went through anesthesia and operation smoothly.Bradycardia and hypotension could be relieved somewhat by medication in operation,and no complete atrio-ventricular block developed.Conclusion There is no need inserting a temporary pacemaker for chronic bifascicular block if asymptomatic and no atrio-ventricular block.Transesophageal atrial pacing is an easy way to evaluate in quantification atrio-ventricular conduction ability.

To improve the extraction of solanesol from tobacco waste, we developed an enzymatic cell wall-breaking process with combined cellulase and ligninase. The effects of reaction time, temperature, pH and enzyme/substrate ratio were determined. The results show that the catalytic effect was better than either single enzyme when the ratio of cellulase to ligninase was 15:1 (U/U). Under the optimized conditions of 175 U/g (enzymes/substrate), tobacco to water 1:5 (W/W), temperature 40 degrees C and pH 6.0, the concentration of solanesol in the solution could reach 0.33 g/L after 8 h. And the average leaching rate reached 96.53% which was 1.68 times of the extraction methods of chemical reflux. It provides new way for the extraction of solanesol from tobacco waste, and worthwhile to be further explored.
Cell Wall ; metabolism ; Cellulase ; metabolism ; Oxygenases ; metabolism ; Plant Leaves ; chemistry ; Terpenes ; isolation & purification ; Tobacco ; chemistry

Poly(ADP-ribose)polymerase-1 (PARP-1) plays a significant role in the DNA repair process by catalyzing the transfer of ADP-ribose from NAD+ to its receptors. It is a promising anticancer drug target and many PARP-1 inhibitors have been developed and used in the clinical trial. In this work, a series of 3-(2-oxo-2-substituted acetamido)benzamides have been synthesized and their inhibitory activities against PARP-1 were evaluated. Of all the tested compounds, six compounds displayed inhibitory activities with IC50 values ranging from 0.23 to 5.78 µmol.L-1 . The binding pose of compound 5a was predicted using molecular docking to facilitate further structural modification.

Objective To investigate the effect of diabetes on the expression of the glucose transporter (GLUT-1) in blood brain barrier (BBB) endothelial cell at different time points. Methods Forty male SD rats were randomly divided into normal control and diabetic group. Diabetic model of SD rats was established by intravenous streptozotocin(50 mg/kg) injection. Ten rats in each group were sacrificed on the 2nd month and 10th month respectively. The rat' s prefrontal cortex was removed to observe the expression of GLUT-1 in BBB EC with immunohistochemical(IHC) staining. Results By IHC method, the number of GLUT-1 positive microvessels was significantly decreased in diabetic group in the 2nd month (4. 3 ± 0. 9) compared with that of control group (6.4 ± 1.7, t = 7. 586, P < 0. 01 ) ; the number of GLUT-1 positive microvessels was significantly increased in the diabetic group in the 10th month (8.4 ± 1.4) compared with that of control group (5. 8 ± 1.7, t = 15.922,P < 0. 01 ). Conclusions Short-term diabetes GLUT-1 expression in BBB EC is downregulated in early stage, while it is upregulated in advanced stage.

The root bark extract of Aralia taibaiensis is used traditionally for the treatment of diabetes mellitus in China. The total saponin extracted from Aralia Taibaiensis (sAT) has effective combined antihyperglycemic and hypolipidemic activities in experimental type 2 diabetic rats. However, the active compounds have not yet been fully investigated. In the present study, we examined effects of twelve triterpenoid saponins on AMP-activated protein kinase (AMPK) activation, and found that compound 28-O-β-D-glucopyranosyl ester (AT12) significantly increased phosphorylation of AMPK and Acetyl-CoA carboxylase (ACC). AT12 effectively decreased blood glucose, triglyceride (TG), free fatty acid (FFA) and low density lipoprotein-cholesterol (LDL-C) levels in the rat model of type 2 diabetes mellitus (T2DM). The mechanism by which AT12 activated AMPK was subsequently investigated. Intracellular ATP level and oxygen consumption were significantly reduced by AT12 treatment. The findings suggested AT12 was a novel AMPK activator, and could be useful for the treatment of metabolic diseases.
Acetyl-CoA Carboxylase ; Adenosine Triphosphate ; AMP-Activated Protein Kinases* ; Animals ; Aralia* ; Blood Glucose ; China ; Diabetes Mellitus ; Diabetes Mellitus, Type 2 ; Metabolic Diseases ; Models, Animal ; Oxygen Consumption ; Phosphorylation ; Rats ; Saponins ; Triglycerides

BACKGROUND:Bone tissue remodeling is closely related to stress loading.Currently,there are few studies or guidelines on the relationship between bone and occlusal adjustment of implant prostheses and there is also a lack of scientific evidence. OBJECTIVE:To investigate the effects of different implant occlusal gaps on stress distribution,stress peak and displacement at the implant-bone interface under Ⅰ-Ⅳ bone conditions by a finite element method. METHODS:After scanning the equal-scale tooth model with an optical scanner,equal-scale models of the upper right first molar Straumann 4.8×8 mm BL RC implant and its related components was constructed using Solidworks 2022.Then,using Mimics,Geomagic,and Solidworks software,the maxillary and mandibular bone models of class Ⅰ-Ⅳ bones were established based on the bone classification proposed by ZARB and LEKHOLM in the literature,and the NORTON and TRISI bone density classification method.The models were assembled with the occlusal gaps of 0,20,40,60,80,and 100 μm for the restorations,and an additional set of homogeneous models without density ratio settings was constructed for comparison.After the above models were imported into Hypermesh for meshing,the material assignment,boundary constraints and parameter setting were performed for the finite element analysis.Finally,250 N was used as the loading force to simulate the maxillary and mandibular stress conditions.Stress distribution,peak stress and displacement of the implant-bone interface in each group of models were analyzed and compared. RESULTS AND CONCLUSION:Under the same loading conditions,the stresses in the implant restorations were evenly distributed with the occlusal contact points.When the occlusal gap reached 80 and 100 μm,stress interruptions occurred in the implant crowns under class Ⅰ bone and class Ⅱ,Ⅲ and Ⅳ bones,respectively.The displacement of the implant-bone interface was mainly concentrated in the cortical bone region around the implant and transmitted down the long axis of the implant to the cancellous bone region at the bottom.With the changes of class Ⅰ-Ⅳ jaw bones,the displacement and Von Mises stress in the cortical bone region increased in all groups,and were greater than those in the cancellous bone region.The Von Mises stress in the cancellous bone region was similar to that in the cortical bone region except that it showed a downward trend from class Ⅱ bone.However,when the occlusal gap increased,the stress and displacement peak values in the cortical bone and the cancellous bone showed a decreasing trend.The stress of the implant-bone interface was between 20 MPa and 60 MPa when the occlusal gap was 0-40 μm for class Ⅱ-Ⅳ bones and 60 μm for class Ⅳ bone,and the stress of the other groups was less than 20 MPa.The Von Mises stress was mainly concentrated in the neck of the implant,and the peak value of von Mises stress in class Ⅱ-Ⅳ bones with the occlusal gap of 20 μm was higher than that(144.10 MPa)in class Ⅰ bone with the occlusal gap of 0 μm.In the homogeneous model with different elastic moduli,the distribution of stress and displacement was more uniform than that in the heterogeneous model and the occlusal space should increase with the decrease of jaw bone density in clinical practice.To conclude,from the perspective of biomechanics,the alveolar bone should be taken into account in the occlusal adjustment of implant denture.An occlusal gap of 20-40 μm between a single dental implant and a natural tooth in the opposite jaw is a relatively suitable solution for occlusal adjustment under different bone conditions.However,due to the particularity of finite element analysis method,it needs to be further studied in combination with clinical practice.

BACKGROUND:Socket-shield technique can effectively maintain labial soft and hard tissues,but the incidence of postoperative complications such as exposure and displacement of root shield is relatively high.It is speculated that the root shield may be exposed and displaced due to excessive load after long-term function of dental implants. OBJECTIVE:Through three-dimensional finite element analysis,we aim to study the influence of varying root shield thicknesses on the stress distribution,equivalent stress peaks,and displacement in the root shield,periodontal ligaments,implant,and surrounding alveolar bone under normal occlusal loading.We also attempt to analyze the correlation between the thickness of the root shield and occurrence of mechanical events such as root shield exposure,displacement,and fracture. METHODS:Cone-beam CT data of a patient who met the indication standard of socket-shield technique for maxillary central incisor were retrieved from database.Reverse engineering techniques were used to build models of the maxillary bone and root shield,while forward engineering was used to create models for the implant components based on their parameters.Models depicting various root shield thicknesses(0.5,1.0,1.5,and 2.0 mm)were created using Solidworks 2022 software.ANSYS Workbench 2021 software was then used to simulate and analyze the effects of varying root shield thicknesses on stress distribution,equivalent stress peaks,and displacement of the root shields,periodontal ligaments,implants,and surrounding alveolar bone under normal occlusion. RESULTS AND CONCLUSION:(1)In all root shield models,the stress was concentrated on the palatal cervical side,both sides of the edges and the lower edge of the labial side.As the thickness of the root shield increased,the equivalent stress peak and displacement showed a decreasing trend.The 0.5 mm thickness model produced a stress concentration of 176.20 MPa,which exceeded the yield strength(150 MPa)of tooth tissue.(2)The periodontal ligament stress in each group was concentrated in the neck margin and upper region.With the increase of root shield thickness,the equivalent stress peak and displacement of periodontal ligament showed a decreasing trend.(3)Implant stress in all models was concentrated in the neck of the implant and the joint of the implant-repair abutment,and the labial side was more concentrated than the palatal side.With the increase of root shield thickness,the equivalent stress peak of the implant in the model showed an increasing trend.(4)In each group of models,stress of cortical bone concentrated around the neck of the implant and the periphery of the root shield,and the labial side was more concentrated than the palatal side.With the increase of the thickness of the root shield,the equivalent stress peak around the root shield decreased;the peak value of the equivalent stress of the bone around the neck of the implant showed an increasing trend.In the model,the stress of cancellous bone was mainly concentrated around the neck of the lip of the implant,the top of the thread,the root tip and the lower margin of the root shield,and the labial side was more concentrated than the palatal side.With the increase of the thickness of the root shield,the peak value of the equivalent stress of the bone around the root shield in the model showed a decreasing trend.The minimum principal stress of cortical bone in each group of models was concentrated around the neck of the implant,exhibiting a fan-shaped distribution.As the thickness of the root shield increased,the minimum principal stress of cortical bone showed an increasing trend.(5)These results indicate that different thicknesses of the root shield have different biomechanical effects.The root shield with a thickness of 0.5 mm is easy to fracture.For patients with sufficient bone width,the root shield with a thickness of 2.0 mm is an option to reduce the risk of complications such as root shield exposure,fracture,and displacement.Meanwhile,it should be taken into account to protect the periodontal ligament in the preparation process,and rounding treatments ought to be carried out on both sides and the lower edge of the root shield.

Objective: To discuss the taxonomy and molecular characteristics of one virus strain (SZC30) isolated from Culicoides in Yunnan. Methods: Culicoides were collected with light trap method in the Wulong Village of Shizong County of Yunnan Province in July, 2013. BHK-21 and C6/36 cells were used for virus isolation. The positive isolates were inoculated into brain of one-day suckling mice. Alphavirus and Getah virus specific primers were used to amplify the genome of the virus isolation by RT-PCR. The products of RT-PCR were sequenced. Clustal X1.83, DNAStar, Mega5.1 were used for bioinformatics analysis. Results: Totally 3 500 culicoides were collected and divided into 41 batches for virus isolation. One isolate (SZC30) produced cytopathic effect (CPE) on BHK-21 and C6/36 cells; the result of RT-PCR with Alphavirus and Getah virus NS1 specific primer were positive; the sequence analysis of NS1 gene suggested that SZC30 and two Getah virus strains (YN0540, SC1210) from China were in the same evolutionary branching, the nucleotide homology were 97%-100%, and the amino acid was 97%-100%. Conclusions SZC30 isolated in Yunnan province was identified as Getah virus.