With the continuous development in microfluidic fabrication technology, microfluidic analysis has evolved from a concept to one of research frontiers in last twenty years. The research of enzymes and enzyme inhibitors based on microfluidic devices has also made great progress. Microfluidic technology improved greatly the analytical performance of the research of enzymes and enzyme inhibitors by reducing the consumption of reagents, decreasing the analysis time, and developing automation. This review focuses on the development and classification of enzymes and enzyme inhibitors research based on microfluidic devices.
Enzyme Inhibitors ; metabolism ; Enzymes ; metabolism ; Microfluidic Analytical Techniques ; methods ; Microfluidics ; methods

OBJECTIVETo investigate the frequency of JAK2 V617F mutation in 145 myeloproliferative disorders (MPDs) patients, analyze the correlation between JAK2 V617F mutation and clinical features.

METHODSThe JAK2 V617F mutation was detected by direct DNA sequencing of PCR product and allele-specific PCR respectively. The expression of JAK2, phospho-JAK2 and phospho-STAT5 proteins was determined by Western blot. The clinical data of MPDs patients with or without JAK2 V617F mutation was collected and analyzed for evaluating the clinical significance of JAK2 V617F mutation.

RESULTS1) The frequency of JAK2 V617F mutation for PV, IMF, ET was 92%, 58%, 50% respectively. Compared with conventional DNA sequencing (PV 84%, IMF 44%, ET 39%, respectively), allele-specific PCR exhibited a higher sensitivity in JAK2 V617F mutation detection. 2) The expression levels of phospho-JAK2 and phospho-STAT5 in peripheral blood mononuclear cells (PBMNCs) were upregulated significantly in JAK2 V617F-positive patients than in JAK2 V617F negative patients. 3) Compared with the patients with no JAK2 V617F mutation, the JAK2 V 617F-positive patients' features were as follows: older age of onset, higher mean leukocyte counts, lower platelet counts and smaller spleen volume. Frequency of thrombosis events in PT, ET, IMF was 17%, 32%, 16% respectively for JAK2 V617F positive group, and 0% (PV), 16% (ET), 5% (IMF) for JAK2 V617F negative group.

CONCLUSIONSMPDs patients display higher frequency of JAK2 V617F mutation. JAK2 V617F mutation positive patients predispose to a thrombosis tendency.

Female ; Humans ; Janus Kinase 2 ; genetics ; metabolism ; Male ; Mutation ; Myeloproliferative Disorders ; genetics ; metabolism ; Phosphorylation ; STAT5 Transcription Factor ; metabolism ; Sequence Analysis, DNA

Objective To investigate the different pathogeneses of asymptomatic lacunar infaction and symptomatic nonlacunar infaction by investigating their risk factors.Methods A total of 1989 people more than 50 years old,performed physical examination were chosen with the results showing 48 patients with asymptomatic lacunar infaction (group A) and 51 patients with symptomatic nonlacunar infaction (group B).Another 1862 controls without cerebrovascular disease were also chosen.Single factor analysis and logistic regression analysis were used to analyze the risk factors.Each risk factor and amount of risk factors for the two diseases was compared between group A and group B.Results Age,hypertension and smoking were the independent predictors of asymptomatic lacunar infaction (P＜0.05).Age,sex,diabetes mellitus,drinking,family history of stroke and stenosis of intracrianial artery were the independent predictors of the symptomatic nonlacunar infaction (P＜0.05).Both rates of diabetes mellitus and stenosis of intracrianial artery in group B were higher than those in group A (diabetes mellitus:x2=17.603,P=0.008; stenosis of intracrianial artery:x2=19.319,P=0.005).The amount of risk factors in patients from group B was significantly more than that in patients from group A (Z=2598,P=0.009).Conclusion The risk factors and vascular mechanism in patients with symptomatic nonlacunar infaction and asymptomatic lacunar infaction are different.Diabetes mellitus and stenosis of intracrianial artery are more often noted in patients with symptomatic nonlacunar infarction.

OBJECTIVETo study the airflow velocity, trace, distribution, pressure, as well as the airflow exchange between the nasal cavity and paranasal sinuses in a computer simulation of nasal cavity pre and post virtual endoscopic sinus surgery (ESS).

METHODSComputational fluid dynamics (CFD) technique was applied to construct an anatomically and proportionally accurate three-dimensional nasal model based on a healthy adult woman's nasal CT scans. A virtual ESS intervention was performed numerically on the normal nasal model using Fluent 6.1.22 software. Navier-Stokes and continuity equations were used to calculate and compare the airflow characteristics between pre and post ESS models.

RESULTS(1) After ESS flux in the common meatus decreased significantly. Flux in the middle meatus and the connected area of opened ethmoid sinus increased by 10% during stable inhalation and by 9% during exhalation. (2) Airflow velocity in the nasal sinus complex increased significantly after ESS. (3) After ESS airflow trace was significantly changed in the middle meatus. Wide-ranging vortices formed at the maxillary sinus, the connected area of ethmoid sinus and the sphenoid sinus. (4) Total nasal cavity resistance was decreased after ESS. (5) After ESS airflow exchange increased in the nasal sinuses, most markedly in the maxillary sinus.

CONCLUSIONSAfter ESS airflow velocity, flux and trace were altered. Airflow exchange increased in each nasal sinus, especially in the maxillary sinus.

Computer Simulation ; Endoscopy ; Humans ; Hydrodynamics ; Maxillary Sinus ; surgery ; Nasal Cavity ; surgery ; Paranasal Sinuses ; surgery

Biochemistry is one of the basic disciplines of life sciences‚ and plays an important role in the undergraduate teaching of biology. However‚ the biochemistry course system is huge‚ and the knowledge is numerous. How to improve students' interest in learning‚ improve teaching effect‚ and promote course construction are important questions faced by many biochemistry teachers. Here the authors put forward the " three-dimensional teaching concept based on FACT" ‚ and take the biochemistry course construction of the School of Life Sciences‚ Sun Yat-sen University‚ as an example to analyze the connotation and practice of this teaching concept. " Three-dimension" is inspired by the " seemingly identical but actually different" concept of biological chiral molecules‚ which not only reflects the need for universities to carry out course construction based on their own actual situation and seek truth from facts with distinct characteristics‚ but also emphasizes the construction of a multi-dimensional course construction system. The authors will introduce the concept of " three-dimension" in “form” ‚ “angle” ‚ “content” and “team” in an all-round way. Moreover‚ the authors also conduct in-depth analysis from aspects such as teaching methods‚ second classroom‚ knowledge point logic‚ ideological and political education for courses‚ and teaching team construction‚ which has certain reference significance for peer teachers to carry out biochemistry course construction.

OBJECTIVETo investigate the effect of solanine on the growth of human prostate cancer cell xenograft in nude mice.

METHODSHuman prostate cancer Du145 cells were injected into the subcutaneous layers on the back of nude mice. After a week, the mice bearing subcutaneous tumor graft were randomly divided into solanine treatment group and saline control group for treatment for 3 weeks. The tumor grafts were then harvested to evaluate the inhibition rate. The mRNA and protein expressions of cell cycle-related genes in the tumors were detected by qRT-PCR and Western blotting, respectively, and tumor cell apoptosis was detected using TUNEL method.

RESULTSThe tumor growth rate in solanine-treated group was significantly slower than that in the control group (P<0.01). The mRNA and protein expressions of C-myc, cyclin D1, cyclin E1, CDK2, CDK4 and CDK6 were significantly inhibited by solanine. Solanine significantly up-regulated p21 mRNA and protein expression in the tumors and induced a higher apoptosis rate of the tumor cells than saline (P<0.01).

CONCLUSIONThe tumor-inhibition effect of solanine is probably mediated by regulating the expressions of genes related with G1/S cell cycle arrest and cell apoptosis.

Animals ; Apoptosis ; Cyclin-Dependent Kinases ; metabolism ; Cyclins ; metabolism ; G1 Phase Cell Cycle Checkpoints ; Humans ; Male ; Mice ; Mice, Nude ; Neoplasm Transplantation ; pathology ; Prostatic Neoplasms ; drug therapy ; pathology ; S Phase ; Solanine ; pharmacology

Aged ; Coronary Angiography ; Coronary Restenosis ; diagnostic imaging ; etiology ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Sirolimus ; administration & dosage ; Stents

OBJECTIVETo evaluate the effectiveness and safety of sirolimus-eluting stents (SESs) for treatment of in-stent restenosis (ISR).

METHODSAll 27 patients with ISR and clinical evidence of ischemia had been treated with SESs. Among them, 23 patients had diffuse and complex lesions, and 5 of them received 2 SESs. Clinical and angiographic follow-up were performed for all patients and the results were analyzed.

RESULTSAll stents were implanted successfully. There were no remained stenosis and major in-hospital complications. Average follow-up time was 8.9 +/- 2.1 (5-14) months, with a clinical follow-up rate of 96.3% and angiographic follow-up rate of 92.6%. During the follow-up, there was none of death. One patient had recurrent angina with an angiographic evidence of the proximal edge restenosis of the stent. Mild neointimal hyperplasia in the proximal edge was found in 2 patients, but the stenosis was less than 25%. No late lumen loss was found in other 24 patients. The late lumen loss of the in-stent averaged 0.09 +/- 0.02 mm, and of the distal edge vessel averaged 0.10 +/- 0.03 mm, and of the proximal edge vessel averaged 0.20 +/- 0.06 mm. The rate of target vessel revascularization was 3.8%.

CONCLUSIONThe SES implantation is safe and feasible for the treatment of in-stent restenosis, which could effectively prevent neointimal hyperplasia and recurrent restenosis of the lesion.

Adult ; Aged ; Coronary Angiography ; Coronary Restenosis ; diagnostic imaging ; therapy ; Female ; Follow-Up Studies ; Humans ; Male ; Middle Aged ; Sirolimus ; administration & dosage ; Stents

OBJECTIVETo establish an improved method for stereotactic location of the supraoptic nucleus in rats.

METHODSTwenty-four SD rats were randomly divided into experimental group (12 rats) and control group (12 rats) for oblique (20° to the left) stereotactic puncture (OSP group) and vertical stereotactic puncture (VSP group), respectively, both targeting the supraoptic nucleus (SON). The surgical data and postoperative (within 24) mortality of the rats were compared between the two groups.

RESULTSThe nucleus locating time was longer in OSP group than in VSP group (59.55∓3.64s vs 27.44∓2.18 s, P=0.000), and the postoperative mortality rate of the rats did not differ significantly between the groups (0 vs 44.4%, P=0.082). In OSP group, compared with VSP group, the procedure was associated with a lowered rupture rate of the superior sagittal sinus (11.1% vs 88.9%, P=0.003), a shortened hemostatic time after craniotomy (52.89∓24.05 s vs 157.445 ime a s, P=0.000) and after puncture (24.33 reas 45 s vs 133.89∓28.81 s, P=0.000), and also a shortened operation time (178.89 on tims vs 362.44 timees, P=0.000).

CONCLUSIONThe improved method for locating supraoptic nucleus in rats is convenient, stable and reproducible, and helps to avoid important blood vessels and specific nuclei according to the needs of different experiments and allows the operators to choose different surgical paths.

OBJECTIVETo analysis the efficacy and safety of lamivudine (made in China) therapy for 52 weeks in adolescent patients with chronic hepatitis B (CHB).

METHODSOne hundred and five teenage CHB patients were treated with lamivudine 100 mg once daily for 52 weeks. Patients with elevated ALT at baseline were in group 1 and those with normal ALT were in group 2. The changes of HBV DNA, HBV seromarkers and ALT at the end of 12, 24 and 52 weeks after lamivudine therapy were compared with those at baseline. Adverse events were recorded and evaluated.

RESULTSAt the end of 52 weeks of lamivudine therapy, HBV DNA-ve, HBeAg loss and anti-HBe seroconversion were observed in 92.0%, 24.4% and 22.0% in group 1 patients and 76.1%, 14.2% and 14.2% in group 2 patients respectively. No significant differences were found between two groups. At 12, 24 and 52 weeks, normalization rates of ALT were 59.0%, 66.7% and 76.0%, normal ALT with undetectable HBV DNA were 44.9%, 64.1% and 70.7% at the same time. During 52 weeks lamivudine treatment 26 mild adverse events were observed in 18 patients.

CONCLUSIONLamivudine can inhibit HBV replication rapidly and normalize ALT in majority adolescent CHB patients. HBeAg loss or seroconversion of anti-HBe was observed in some of these patients. All patients in this study were safety and well tolerated.

Adolescent ; Alanine Transaminase ; blood ; Antiviral Agents ; adverse effects ; therapeutic use ; Child ; DNA, Viral ; blood ; Female ; Hepatitis B Antibodies ; blood ; Hepatitis B e Antigens ; blood ; immunology ; Hepatitis B virus ; genetics ; Hepatitis B, Chronic ; drug therapy ; immunology ; Humans ; Interferons ; administration & dosage ; therapeutic use ; Lamivudine ; adverse effects ; therapeutic use ; Male ; Mutation ; genetics ; Reverse Transcriptase Inhibitors ; adverse effects ; therapeutic use ; Safety ; Treatment Outcome