AIMTo observe the effect of stretching left ventricles in the end of action potential on rabbit cardiac activity, and to investigate its possible mechanisms.

METHODSStretch (120 mmHg, 50 ms) was applied in the end of action potential by the pressure-clamp technique to observe if there would be any changes in rabbit cardiac activity and streptomycin (500 micromol/L) was used to identify the mechanism.

RESULTSStretch in the end of action potential caused arrhythmia (P < 0.05) and streptomycin blocked the above effect (P < 0.05).

CONCLUSIONStreptomycin could block the effect of stretching left ventricles in the end of action potential on rabbit cardiac activity, which indicates that stretch-activated ion channels involve it.

Action Potentials ; physiology ; Animals ; Arrhythmias, Cardiac ; etiology ; physiopathology ; Female ; Heart Ventricles ; physiopathology ; In Vitro Techniques ; Ion Channels ; physiology ; Male ; Mechanoreceptors ; drug effects ; Proprioception ; Rabbits ; Streptomycin ; pharmacology

OBJECTIVETo develop a system for automatically controlling carotid sinus pressure in the study on baroreceptors.

METHODSThe preparation containing carotid sinus with parts of the connected vessels and carotid sinus nerve (CS-CSN) were isolated and perfused. A critical pressure controlling component (PRE-U, Hoerbiger, Deutschland) dictated by a computer was integrated into the system to clamp the intrasinus pressure. The pressure command and the relevant intrasinus pressure were compared to evaluate the validity of the pressure controlling system.

RESULTSA variety of sinus pressure-controlling patterns, including pulsation, ramp and step pressures, could be achieved accurately by using the system, and the pressure-dependent discharge activities of sinus nerve were confirmed.

CONCLUSIONThis system for clamping carotid sinus pressure could realize multiple pressure-controlling patterns and is a useful and flexible pressure controlling method that could applied in the study on mechano-electric transduction of baroreceptors.

Animals ; Blood Pressure ; Carotid Sinus ; innervation ; physiology ; Nerve Fibers ; physiology ; Pressoreceptors ; physiology ; Rabbits

It is necessary to control the mechanical stimuli precisely in the studies of cardiac mechano-electrical feedback (MEF). In the present study a ventricular pressure-clamping system has been developed, which can be applied to isolated-perfused rabbit hearts. Controlled by a computer, this system not only can make the left ventricle follow a command defining the same pressure wave as that during a beating cycle under physiological condition, but also deliver mechanical stimuli with a proper waveform to the ventricle at a particular time phase. This system integrates multiple functions, including perfusing, pacing, recording of electrocardiogram and monophasic action potentials, and clamping and measuring of ventricular pressures in isolated-perfused hearts. Thus, it is a distinct system for investigating the phenomena and mechanisms of cardiac MEF at organ level.
Action Potentials ; Animals ; Constriction ; Electrocardiography ; Feedback ; Heart ; physiology ; In Vitro Techniques ; Rabbits ; Ventricular Pressure

BACKGROUNDBaseline white blood cell (WBC) count was correlated with ischemic events occurrence in patients with ST-elevated myocardial infarction (STEMI). However, circulating WBC count is altered after percutaneous coronary intervention (PCI). The aim of this study was to assess the relationship between postprocedural WBC count and clinical outcomes in STEMI patients who underwent PCI.

METHODSA total of 242 consecutive acute STEMI patients who underwent successful primary PCI were enrolled and followed up for two years. WBC counts were measured within 12 hours after PCI. ST-segment resolution (ST-R) and myocardial blush grades (MBG) were evaluated immediately after PCI. Left ventricular ejection fraction (LVEF) was obtained at baseline and 12 - 18 months after PCI.

RESULTSPostprocedural WBC count was an independent inverse predictor of ST-R (OR 0.80, P < 0.0001) and MBG 3 (OR 0.82, P < 0.0001). It was negatively correlated with LVEF (baseline r = -0.22, P = 0.001; 12 - 18 months r = -0.29, P < 0.0001). The best cutoff value of WBC for predicting death was determined to be 13.0 × 10(9)/L. The patients with a postprocedural WBC count above 13.0 × 10(9)/L showed a significantly lower cumulative survival rate (30 days, 82.4% vs. 99.0%, P < 0.0001 and 2 years 75.0% vs. 96.4%, P < 0.0001). Multivariate Cox regression analysis showed that a postprocedural WBC count was a strong independent predictor of 30-day mortality (HR 8.48, P = 0.019) and 2-year mortality (HR 4.93, P = 0.009).

CONCLUSIONSIncreased postprocedural WBC count is correlated with myocardial malperfusion and left ventricular dysfunction, and is an independent predictor of poor clinical outcomes in STEMI patients who underwent PCI.

Adult ; Aged ; Angioplasty, Balloon, Coronary ; Electrocardiography ; Female ; Humans ; Leukocyte Count ; Male ; Middle Aged ; Myocardial Infarction ; blood ; physiopathology ; therapy ; Predictive Value of Tests ; Proportional Hazards Models ; Treatment Outcome ; Ventricular Function, Left

OBJECTIVETo investigate the gene mutation and the molecular pathogenesis of an inherited coagulation factor VII (F VII) deficiency pedigree with consanguineous marriage.

METHODSThe diagnosis was validated by coagulant parameter assay on the prothrombin time (PT), activated partial thromboplastin time, fibrinogen and coagulation factor activity. F VII gene mutations were analyzed in the proband and other family members by direct DNA sequencing of the PCR products of all exons, exon-intron boundaries and 5'and 3' untranslated sequences. The mutations were confirmed by reverse sequencing.

RESULTSThe values of PT and F VII activity in the proband were significantly abnormal, they were 30.9 s and 3% respectively. The PT of her daughter, father and mother was slightly extended to 21.2 s, 16.3 s and 16.1 s respectively, and the F VII activity was reduced to 22%, 25% and 35% respectively. The coagulant parameters of her younger brother were within normal range. Homozygous T-->G transition at position 11482 in exon 8 was identified in the proband resulting in His348Gln, and heterozygosity for His348Gln was confirmed in her daughter and her parents, and the normal wild-type was observed in her younger brother.

CONCLUSIONHomozygous missense mutation of His348Gln was found in a pedigree of hereditary F VII deficiency. The mutation was inherited from her heterozygote parents.

Adolescent ; Adult ; Aged ; Factor VII ; genetics ; Factor VII Deficiency ; genetics ; Female ; Homozygote ; Humans ; Infant, Newborn ; Male ; Middle Aged ; Mutation, Missense ; Pedigree

OBJECTIVEThe aim of the study was to evaluate the prognostic value of the postprocedural neutrophil count in patients with first acute ST elevation myocardial infarction (STEMI) treated with successful primary percutaneous coronary intervention (PCI).

METHODSA total of 226 consecutive STEMI patients underwent successful primary PCI were enrolled. Electrocardiograms were recorded before PCI and 2 hours after PCI. Neutrophil counts were measured within 12 hours after PCI. All patients were followed up for 2 years. Logistic regression analysis was used to evaluate predictive values of postprocedural neutrophil for ST-segment resolution (STR) after PCI and for death, non-fatal myocardial infarction and heart failure at 30 days and 2 years post PCI. Time-to-event analyses were performed using the Kaplan-Meier survival curves in patients with various ranges of postprocedural neutrophil counts.

RESULTSPostprocedural neutrophil count ranged from 2.83x10(9)/L to 18.74x10(9)/L, first quartile, median and fourth quartile were 5.66x10(9)/L, 7.38x10(9)/L and 9.34x10(9)/L respectively. Multivariable logistic analysis showed that when postprocedural neutrophil count increased 1x10(9)/L, the risk of non-STR increased 2.28 fold (OR: 2.28, P=0.009), the risk of death (OR: 1.63, P=0.010) and heart failure (OR: 1.16, P=0.035) at 30 days increased 1.63 and 1.16 folds respectively, and the risk of death (OR: 1.29, P=0.003) and heart failure (OR: 1.20, P=0.007) at 2 years increased 1.29 and 1.20 folds respectively, but the risk of non-fatal myocardial infarction was not affected by postprocedural neutrophil count. Furthermore, the patients with postprocedural neutrophil count>or=9.34x10(9)/L had significant lower 30-day (89.1% vs. 99.1% vs. 98.2%, P=0.010) and 2-year (82.4% vs. 96.1% vs. 96.3%, P=0.003) survival rates compared with the patients with postprocedural neutrophil count from 5.66x10(9)/L to 9.33x10(9)/L and the patients with postprocedural neutrophil count<5.66x10(9)/L (all P<0.05).

CONCLUSIONPostprocedural neutrophil count is an independent predictor of short- and long-term death and heart failure in first acute STEMI patients treated with successful primary PCI.

Aged ; Aged, 80 and over ; Angioplasty, Balloon, Coronary ; adverse effects ; Emergency Treatment ; adverse effects ; Female ; Follow-Up Studies ; Humans ; Leukocyte Count ; Leukocytosis ; Male ; Middle Aged ; Myocardial Infarction ; blood ; diagnosis ; therapy ; Neutrophils ; Prognosis

OBJECTIVETo perform gene analysis and family survey of a patient with combined inherited FVII and FX deficiency, and to identify the gene mutation of this patient.

METHODSThe phenotype diagnosis was validated by coagulant parameter assay on prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen, FVII and FX activity (FVII:C, FX:C) and FVII and FX antigen (FVII:Ag, FX:Ag). FVII and FX gene mutations were analyzed in the proband and other family members by DNA direct sequencing of all exons, exon-intron boundaries and 5', 3' untranslated sequences. One hundred and six health examination participants were selected as control.

RESULTSThe values of PT and APTT of the proband showed significantly prolonged, which were 84.5s and 63.4s, respectively. The levels of FVII:C, FVII:Ag, FX:C and FX:Ag were 6%, 7%, 4% and 30%, respectively. The PT of his father, mother and sister was prolonged slightly while both APTT and FVII:Ag were in the normal range. Two homozygous mutations, g.11267C→T in exon 8 of FVII gene resulting in the substitution of Arg277Cys and g.28139G→T in exon 8 of FX gene leading to the substitution of Val384Phe, were identified in the proband. The proband's parents and sister were heterozygous for Arg277Cys and Val384Phe mutations.

CONCLUSIONHomozygous mutation Arg277Cys in FVII gene and Val384Phe in FX gene were the molecular mechanism causing combined inherited FVII and FX deficiency. The Val384Phe substitution was a novel mutation, which may affect the synthesis or secretion of FX protein.

Adolescent ; Adult ; Base Sequence ; DNA Mutational Analysis ; Factor VII ; genetics ; Factor VII Deficiency ; complications ; genetics ; Factor X Deficiency ; complications ; genetics ; Female ; Heterozygote ; Humans ; Male ; Middle Aged ; Mutation ; Pedigree ; Young Adult

OBJECTIVETo retrospectively investigate the distribution in kidney transplantation for fifteen years in Peking Union Medical College Hospital.

METHODSWe conducted a descriptive research counting up the number of patients who received kidney transplantation each year in our hospital during 1995 and 2010.

RESULTSThe first kidney transplantation in our hospital occurred in the 1960s. The number of kidney transplantation increased until reaching a maximum of 47 grafts in 2001; since then the number fell.

CONCLUSIONSWith the decreased number of kidney transplantation, we have realized the shortage of transplantable organs is very serious. The continuing transplant shortage requires major efforts to expand the donor pool. Donation after cardiac death offers the potential to enlarge the donor pool, but we need to strictly control the criteria for potential donors.

China ; Humans ; Kidney Transplantation ; methods ; statistics & numerical data ; trends ; Postoperative Complications ; epidemiology ; Retrospective Studies ; Time Factors ; Tissue Donors ; statistics & numerical data ; Tissue and Organ Procurement ; statistics & numerical data ; trends ; Treatment Outcome

OBJECTIVETo fabricate polyvinyl alcohol (PVA)/chitosan hybrid nanofibrous scaffolds owning the similar physiological structure of ECM, and to observe its biodegradation behavior in vivo and in vitro.

METHODS(1) The PVA nanofibrous scaffold and PVA/chitosan hybrid nanofibrous scaffold were fabricated by electrospinning technique, and then they were crosslinked by glutaraldehyde vapor method. The morphology of both scaffolds was observed by scanning electron microscope (SEM). (2) Biodegradation experiment in vitro: the samples of two scaffolds with size of 2 cm x 2 cm were placed into phosphate-buffer saline (PBS) fluid under 37.0 degrees C water for incubation, and then they were dried to observe morphologic changes under SEM on post incubation day (PID) 3, 7, and 14. (3) Biodegradation experiment in vivo: 48 Wistar rats were divided into PVA group and PVA/chitosan group according to the random number table, with 24 rats in each group. PVA or PVA/chitosan nanofibrous scaffold was implanted into subcutaneous tissue on both sides of back in rats of both groups, with 4 scaffolds in each rat. The scaffold samples were harvested to observe morphologic changes with HE staining on post operation day (POD) 3, 7, 14, and 28.

RESULTS(1) After crosslinking, the surface of fibers in PVA and PVA/chitosan hybrid nanofibrous scaffolds were smooth, and the diameters of fibers were similar, ranging from 200 to 300 nm, with high porosity. (2) Biodegradation experiment in vitro showed that the morphologic changes in fiber was respectively swelling, dissolution, fusion in PVA nanofibrous scaffold on PID 3, 7, 14, and that in PVA/chitosan hybrid nanofibrous scaffold was respectively swelling, dissolution and fragmentation, and disappearance. (3) Biodegradation experiment in vivo showed that the morphologic changes in scaffold structure was respectively loosening, fuzziness of edges, degradation, and disappearance in PVA group and PVA/chitosan group on POD 3, 7, 14, 28.

CONCLUSIONSPVA/chitosan hybrid nanofibrous scaffolds can be prepared with electrospinning technique, and it has an appropriate biodegradation rate compatible with tissue reconstruction after crosslinking.

Animals ; Biocompatible Materials ; Cells, Cultured ; Chitosan ; chemical synthesis ; chemistry ; Materials Testing ; Polyvinyl Alcohol ; chemical synthesis ; chemistry ; Rats ; Rats, Wistar ; Tissue Engineering ; methods ; Tissue Scaffolds

Antibodies, Monoclonal, Murine-Derived ; therapeutic use ; Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Humans ; Lymphoma, Follicular ; drug therapy ; Rituximab