Atrial fibrillation is one of common arrhythmias and can significantly increase risks of stroke and heart failure with high rates of mortality and disability. The incidence of atrial fibrillation increases year by year due to aging population, high incidences of coronary heart disease and hypertension, and lifestyle changes. As one of widely consumed drinks in the world, coffee affects the daily life of modern people. The intake of caffeine, which is the main ingredient of coffee, can influence the incidence of atrial fibrillation, but the relationship between them is still controversial. Most studies deem that the intake of caffeine is negatively correlated with the incidence of atrial fibrillation. This paper reviews current studies in China and abroad on the relationship between the intake of caffeine and the incidence of atrial fibrillation.

Objectives To investigate the etiological factors,clinical features and treatment of pediatric primary spontaneous pneumothorax (PSP). Methods The clinical data of 84 PSP patients under the age of 18 from Departments of Emergency,Respiratory Diseases and Thoracic Surgery of our hospital from June 1999 to June 2009 were collected. There were 72 males (85.7%) and 12 females (15.3%) with a ratio of 6 to 1. Their age ranged from 14 to 18 (mean 17.06). Patients with pneumothorax following trauma,pneumonia,iatrogenic and other underlying causes were excluded. Therapeutic methods included oxygen therapy for 4.8% patients,closed drainage of pleural cavity for 57.1% patients,and surgery for 38.1% patients,But there were 31 patients receiving surgical treatment after closed drainage was failed. The period of follow-up ranged from 1 to 123 months (mean 25.73 months) through telephone or outpatient. Results Eighty-four patients were included,of whom 96.4% had chest pain,7.1% had chest tightness,66.7% had dyspnea,8.3% had shortness of breath and 14.3% had cough. There were 96.4% patients having decreased breathing sound and 3.6% having absent breathing sound. Bullae or blebs occurred mostly in apex and upper lobe. Twenty-one patients suffered from recurrent pneumothorax. Smokers (66.7%,n=9) had higher recurrent rate than non-smokers (22.0%,n=75). Conclusion PSP should be considered when symptoms such as chest pain and dyspnea appear in teenagers. Closed drainage of pleural cavity combined with surgical procedure is recommended for treatment. PSP patient with a history of smoking has higher recurrent rate of PSP.

Objective To investigate the medial-lateral tilting of patella in two different coordinate systems before and after total knee arthroplasty (TKA). Methods Six fresh-frozen left low limbs from cadaver were tested using a modified Oxford Rig. Anatomically based multiple loading of the quadriceps mechanism was applied(Vastus medialis 24.5 N, Vastus intermedius/rectus femoris 29.4 N, Vastus lateralis 19.6 N). In a three dimensional coordinate system, patellar tilting was tracked using a custom-made Laser tracking device. The femoral trochlea was used as the other coodinate system in skyline view of patellar-femoral joint. Total knee arthroplasty was performed using PFC? posterior cruciate ligament substituting knee system. The tilting angles of patellar were measured before and after TKA. Results In three dimensional coordinate system, when knee flexed 30?,60?,90?,120?,150?, the patella titled :-3.10??2.25?,2.50??1.07?,5.46??2.60?,6.32??2.16?,-2.10??1.90? respectively before total knee arthroplasty was undertaken. After total knee arthroplasty, the patella tilted 3.24??0.35?,2.30??1.39?,1.65??1.17?,1.29??1.03?,-0.86??1.42? respectively. When femoral trochlea was taken as coordinate, the patella tilted 0??0?,0??0?,0??0?,0.24??0.35?,-3.21??1.80?; 0??0?,0??0?,0??0?,0??0?,-1.12??1.20? respectively both before and after TKA (Lateral patella tilting was defined as positive and medial patella tilting, negative). Conclusion Even the relationship between patella and femoral trochlea remains normal, the mode and magnitude of patellar tilting changes significantly after TKA. In early flexion of knee joint, patella tilts medially before TKA while it tilts laterally after TKA. After TKA, patella tilts less laterally than it does before TKA when a knee flexes from 60 to 120 degrees.

Objective To investigate the coupling of tibial rotation and extension-flexion motion of knee joint both before and after total knee arthroplasty. Methods Six fresh-frozen left lower limbs from cadavers were tested using a modified Oxford motor rig for the knee joint. Anatomically based multiple loadings of the quadriceps mechanism were applied (Vastus medialis: 24.5 N, Vastus intermedius/rectus femoris: 29.4 N, Vastus lateralis: 19.6 N). The tibial rotation was tracked using a custom-made laser tracking device while the tibial-femoral flexion was measured with goniometer. Total knee arthroplasty (TKA) was performed using ?PFC-PS posterior cruciate ligament substituting knee system. Results Before TKA, when the knee flexed 10?, 20?, 30?, 60?, 90?, 120? and 150?, tibia rotated 5.1??2.3?, 9.3??3.3?, 10.2??4.8?,11.7??3.5?, 13.5??8.4?, 22.0??8.6? and 29.6??9.3? respectively. After TKA, tibia rotated -2.2??1.7?, -2.5??1.5?, -2.0??1.3?, 1.7??2.5?, 3.9??2.4?, 13.5??6.1? and 18.6??4.7? respectively (Tibial rotation was defined as 0? in knee extension; internal rotation as positive and external rotation as negative). Conclusion The tibial internal rotation is coincident with tibial-femoral flexion, its magnitude of tibial rotation varies in different degrees of knee flexion. The tibial internal rotatation is significant in early knee flexion(0? to 30?), then enters into a platform stage on knee bending from 30? to 90?, Once the knee bends over 90?, the tibia rotates internally markedly again, maximum internal rotation is achieved in fully flexion, probably due to relaxation of soft tissue. After TKA, in early flexion (0? to 30?) the external rotation occurs abnormally, but later on 30? to 150?, it rotates again intenally as normal.

The aim of this study was to explored the mechanism of inhibitory effect of chloroquine on IL-6 release induced synergistically by bacterial DNA and endotoxin. Before experiment mice were sensitized for 1 hour with D-GalN by I.P. injection. Mortality within seven days was observed after mice were challenged with CpG ODN or LPS with or without chloroquine treatment. ANA-1 cell line cells were cultivated in vitro. We investigated the influence of chloroquine on IL-6 release induced by both EC DNA and LPS. Expressions of TLR4 and TLR9 and activation of NF-?B p65 were investigated in cultured THP-1 cells pretreated with chloroquine and stimulated by EC DNA and LPS. The results showed that all mice died within 4 hours after challenged with CpG ODN and LPS. Only 4 or 5 mice pretreated with chloroquine (30mg/kg) died after challenged with CpG ODN and LPS (P

Blood-brain barrier is a natural protection for human body. It protects central nervous system from the interruption and damage of xenobiotics. However, it prevents potential drugs aimed at central nervous system, thus becomes an obstruction for the development of central nervous system drugs. The recent development of blood-brain barrier permeability research and several lead optimization strategies to improve blood-brain barrier permeability are reviewed. These structure optimization methods include increasing lipophilicity, reducing hydrogen bond doners, simplifying molecule, increasing rigidity, lowering polar surface area, avoiding acid group, prodrug strategy, modifying into active transporter's substrates, as well as avoiding P-glycoprotein recognized structures.
ATP-Binding Cassette, Sub-Family B, Member 1 ; metabolism ; Biological Transport ; Blood-Brain Barrier ; Central Nervous System ; drug effects ; Central Nervous System Agents ; pharmacokinetics ; Drug Design ; Humans ; Permeability ; Xenobiotics ; adverse effects

Blood-brain barrier is a natural protection for human body. It protects central nervous system from the interruption and damage of xenobiotics. However, it prevents potential drugs aimed at central nervous system, thus becomes an obstruction for the development of central nervous system drugs. The recent development of blood-brain barrier permeability research and several lead optimization strategies to improve blood-brain barrier permeability are reviewed. These structure optimization methods include increasing lipophilicity, reducing hydrogen bond doners, simplifying molecule, increasing rigidity, lowering polar surface area, avoiding acid group, prodrug strategy, modifying into active transporter's substrates, as well as avoiding P-glycoprotein recognized structures.

ObjectiveTo investigate the effects of platelet derived growth factor (PDGF) on brain cell apoptosis rate and serum neuron-specific enolase (NSE) concentration after hypoxic-ischemic brain damage (HIBD) in neonatal rats. MethodsForty-eight HIBD models of 7-day old neonatal Wistar rats were established and then divided into two groups randomly:PDGF group and normal saline control group (n =24 in each).Another 24 neonatal Wistar rats were taken into the sham operation group.The treatment group received intraperitoneal injection of PDGF-BB (50 ng/kg) once,while the other two groups received normal saline at the same time.In each group,rats were randomly sacrificed immediately at 12,24 and 72 hours after injection (n=8).The serum of rats were reserved for NSE concentration determination by enzyme linked immunosorbent assay,and the right brains of the sacrificed rats were used to prepare brain cell suspension for neurocyte apoptosis rate examination by flow cytometry.Mono-variate analysis and q-test were performed for statistical analysis. Results(1) The brain cell apoptotic rates of treatment group [ (6.09 ± 0.70)％,(9.67 ± 1.52) ％ and (14.15±1.52)％] and control group [(8.00± 1.10)％,(11.45±2.42)％ and (22.90±2.03) ％] were significantly increased compared to that of sham group [(2.11 ± 0.54)％,(2.34 ±0.46)％ and (2.21±0.49)％] at all time points (all P＜0.01 or ＜0.05),the apoptotic rate of treatment group was lower than that of control group (P＜0.01 or ＜0.05).Statistical differences were found among the three groups at 12,24 and 72 hours (F =39.01,66.60 and 194.20respectively; P＜0.01).(2) Serum NSE concentration was significantly increased in the treatment group [(8.43 ± 0.17) μg/L,(6.73 ± 0.16) μg/L and (6.12 ± 0.13) μg/L] and control group [(10.04±0.19) μg/L,(9.330.15) μg/L and (8.36 ± 0.16) μg/L] than in the sham group [(4.22±0.53) μg/L,(3.96±0.60) μg/L and (3.59±0.55) μg/L] at all time points,and it was significantly lower in treatment group than in control group (P＜ 0.01).Statistical difference was found among three groups at 12,24 and 72 hours (F=371.25,245.61 and 236.22 respectively,P＜0.01). ConclusionsPDGF might have neuroprotective effect,which could inhibit apoptosis of neural cells and decrease the serum NSE concentration.

There is a high degree of information asymmetry in medical services.Public hospitals are characteristic of the nature of multi-layer principal-agent relationships.Asymmetric information can lead to inconsistent value goals between the principal and the agent,giving birth to the government regulation capture as a result.Such capture ranks a fundamental cause for diluted public welfare nature of public hospitals.To offset such capture at public hospitals calls for reconstruction of government regulation system within the framework of public hospital corporate governance at an institution level.It is also necessary to eliminate the information asymmetry and its negative results,bringing public hospitals back on track to public welfare.

Arrhythmias, Cardiac ; physiopathology ; Electromyography ; methods ; Female ; Humans ; Infant, Newborn ; Male