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.

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 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 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 investigate the value of contrast-enhanced ultrasound in the differential diagnosis of solid focal lesions of pancreas (s-FLPs).

METHODSWe retrospectively analyzed the clinical data of 56 s-FLPs examined with contrast agent combined with low mechanical indicators contrast-enhanced ultrasound.

RESULTSThe surrounding pancreas parenchyma enhancement time, lesion enhancement time, and peak enhancement time between different groups of s-FLPs had no significant differences (P > 0.05), while the beginning to peak enhancement time showed significant difference (P < 0.05). When using the enhancement speed as a diagnostic indicator to differentiate pancreatic carcinoma from tumor-like pancreatitis, the sensitivity, specificity, and accuracy were 90.5%, 71.4%, and 85.7% for pancreatic carcinoma and 75.0%, 91.7%, and 89.3% for tumor-like pancreatitis. When using the enhancement pattern as a diagnosis indicator to differentiate pancreatic carcinoma from tumor-like pancreatitis, the sensitivity, specificity, and accuracy were 85.7%, 78.6%, and 83.9% for pancreatic carcinoma and 75.0%, 100%, and 94.6% for tumor-like pancreatitis. When different indicators were combined, enhancement pattern and enhancement speed showed the best diagnostic results; however, the Youden index was not improved.

CONCLUSIONSDifferent s-FLPs show different enhancement findings on contrast-enhanced ultrasound. The enhancement pattern and enhancement speed are the most useful diagnostic indicators.

Diagnosis, Differential ; Humans ; Pancreas ; diagnostic imaging ; Pancreatic Neoplasms ; diagnostic imaging ; Pancreatitis ; diagnostic imaging ; Retrospective Studies ; Ultrasonography

OBJECTIVETo evaluate the clinical performance of an innovative contrast-enhanced ultrasound (CEUS) technique in characterization of focal liver lesions (FLL).

METHODSCEUS was performed in 505 patients with FLLs. A sulfur hexafluoride-filled microbubble ultrasound contrast agent and a continuous real-time imaging technique of contrast pulse sequencing were used. The observation items included initial nodule enhancement time, enhancement level and pattern, and dynamic evolution of enhancement along with the CEUS phases.

RESULTSThere were similar findings for both malignant and benign FLLs in initial enhancement time and enhancement level on CEUS. The dynamic evolution of enhancement along with enhancement phase was the most significant parameter for characterization of FLLs. Most malignant lesions showed enhancement at arterial phase and hypo-enhancing at late phase, whereas the benign lesions presented enhancement at arterial phase and persistent hyper- or iso-enhancing until late phase. Using these characteristics as a diagnostic criteria, the sensitivity, specificity, positive predicative value, negative predicative value and accuracy of CEUS in identifying malignant FLLs were 95.7% (313/327), 86.0% (153/178), 92.6% (313/338), 91.6% (153/167) and 92.3% (466/505), respectively.

CONCLUSIONSCharacterization of FLLs by using the innovative CEUS technique is recommendable due to its safety, facility and high accuracy.

Adult ; Aged ; Aged, 80 and over ; Diagnosis, Differential ; Female ; Humans ; Liver Diseases ; diagnostic imaging ; Male ; Middle Aged ; Sulfur Hexafluoride ; Ultrasonography ; methods

OBJECTIVETo evaluate the feasibility, safety and short-term outcomes of laparoscopy-assisted distal gastrectomy for advanced gastric cancer.

METHODSFrom January 2007 to June 2008, 135 patients with advanced gastric cancer in the lower or middle stomach were operated, of whom 66 underwent laparoscopy-assisted distal gastrectomy(LADG) with D2 dissection of lymph nodes and 69 received conventional open D2 distal gastrectomy(ODG). Clinical data were recorded and compared between the two groups.

RESULTSThere were no significant differences in age, gender, and TNM staging between LADG and ODG(all P>0.05). All the patients in the LADG group underwent gastrectomy and lymph nodes dissection successfully without conversion to open surgery and no operative deaths occurred. The operative time was significantly longer for the LADG group than for the ODG group[(266.1±55.1) min vs. (223.8±26.8) min)]. The patients in the laparoscopic surgery group had less blood loss[(131.9±88.7) ml vs.(342.3±178.7) ml], earlier recovery of bowel activity[(3.18±1.22) d vs.(4.50±1.59) d], and shorter hospitalization time[(9.20±3.39) d vs. (11.35±4.61) d]. No significant differences were found in the total number of retrieved lymph nodes(25.81±12.53 vs. 27.47±10.28). The morbidity of complications was comparable between two groups(6.1% vs. 15.94%). No mortality and recurrence were observed during a follow-up period of 1-19 months.

CONCLUSIONSLADG with D2 lymph node dissection is a safe and feasible procedure with adequate lymphadenectomy for advanced gastric cancer.

Female ; Gastrectomy ; methods ; Humans ; Laparoscopy ; Laparotomy ; Male ; Middle Aged ; Retrospective Studies ; Stomach Neoplasms ; surgery ; Treatment Outcome