Objective To summarize the clinical features of patients suffering from pulmonary embolism (PE) with D-dimer ＜ 0. 5 μg/mL in order to raise the diagnostic accuracy and reduce the mortality rate of PE. MethodsD-dimer-negative patients with suspected PE were admitted from January 2006 through December 2009. A comparison of clinical features including clinical manifestations, vital signs, laboratory and ancillary findings between 16 patients finally diagnosed PE and 41 patients without PE. ResultsCompared with patients without PE, the D-dimer-negative patients with PE usually had past history of venous thromembolism (VTE) or recent surgery. The symptoms of chest tightness, acute dyspnea, tachypnea, lower extremity edema and typical S I QⅢTⅢ changes of ECG were more often occurred in patients with PE than those in patients without PE of control group. ConclusionsD-dimer test is a good screening test for acute PE because its negative predictive value is high, but when the patients have acute dyspnea, lower extremity edema, previous history of VTE or/and recent surgery and ECG SI QⅢ TⅢ changes, even if D -dimer ＜ 0. 5 μg/mL, clinicians also should pay attention to and if necessary, further tests should be considered to confirm the diagnosis of PE.

Acute-on-chronic liver failure is a common form of liver failure characterized by complicated clinical manifestations and high mortality.The pathophysiology of ACLF is still unclear.More efficacious treatments are based mainly on a better understanding of the pathophysiology of ACLF.The advances in the pathophysiology of ACLF have been extremely encouraging in the last few years.In this article,we reviewed the progress of ACLF,its definition,etiology and,pathophysiology.

Objective To investigate the expressions and correlation between Survivin and PTEN proteins in astrocytoma.Methods The expressions of Survivin and PTEN proteins were examined by immunohistrochemistry in astrocytoma specimens from 65 patients with astrocytoma.Results The positive expression rate of Survivin in astrocytoma grade Ⅱ was significantly lower than that in grade Ⅲ and grade Ⅳ(all P

Objective To investigate the role of IL-6 in the co-cultivation system of porcine hepatocytes with bone marrow mesenchymal stem cells (MSCs) in vitro.Methods Mononuclear cells were isolated from bone marrow aspirate of swines (n = 3) by 1.077 g/ml density gradient centrifugation.MSCs of passage 3 and primary hepatocytes harvested by a two-step in situ collagenase perfusion technique were inoculated in Millicell culture inserts at a seeding ratio of 1:2,and functional changes of heterotypic interactions were characterized.Levels of IL-6,TNF-α,and TGF-α were measured respectively.Results Hepatocyte viability was greater than 95%.Hepatocyte performance levels such as albumin secretion and urea synthesis were all significantly enhanced in co-culture group compared with hepatocyte homo-culture (P＜0.05).The IL-6 level also significantly increased in co-culture group (P ＜ 0.01).A significant decrease of hepatic functions was observed upon neutralization of IL-6 in co-culture.Conclusion MSC-derived IL-6 plays a key role in the up-regulation of hepatocyte functions in this co-culture.

Objective To establish porcine hepatocyte co-culture system with bone marrow mes-enchymal stem cells (MSCs) in vitro for the ideal cell source of bioartificial liver. Methods Mononu-clear cells were isolated from bone marrow aspirate extracted from the anterior superior lilac spine of swines (n=3) by 1.077 g/ml density gradient centrifugation. MSCs of passage 3 and primary hepato-cytes harvested by a two-step in situ collagenase perfusion technique were randomly distributed, and the morphological and functional changes of heterotypic interactions were characterized. Results The purity of the third passage MSCs and primary hepatoeytes was more than 90 % and 99%, respectively.Hepatocyte viability was greater than 95 %. A rapid attachment and self-organization of three-dimen-sional hepatocyte spheroids were encouraged in co-culture. Heterotypic junctions remained similar to that of hepatocytes in vivo. Hepatocyte performance levels such as albumin secretion and urea synthe-sis were all significantly enhanced in co-culture group compared with hepatocyte homo-culture (P<0.05). The best hepatic function levels were achieved on day 2 and moderately decreased in the following co-culture days. Conclusion Co-cultivation of porcine hepatocytes and MSCs may preserve hepatocyte morphology and function, which could contribute to the functional bioartificial liver.

Objective To explore the correlation of the radius and respiratory variation of inferior vena cava(IVC)with central venous pressure(CVP)for rapid evaluation of blood volume with ultrasound in elderly patients with septic shock.Methods The radius of IVC was measured using bedside ultrasound,respiration variation index(RVI)was calculated as following:RVI =(maximum radius-minimum radius)/maximum radius × 100％ and central venous pressure(CVP)was also recorded in 28 elderly patients with septic shock before and during 2 h and 6 h fluid recovery.Radius and RVI of IVC were compared between 28 shock patients and 22 healthy volunteers as control.Correlation of radius and RVI of IVC with CVP were analyzed.The thresholds of radius and RVI of IVC to estimate CVP 8 mmHg were determined by Receiver Operator Characteristic Curve (ROC)curves.Results The maximum and minimum radius[(1.23±0.28)cm and(0.48±0.18)cm]in the elderly patients with septic shock were smaller than in control group[(1.95±0.14)cm and (1.73±0.13)cm].RVI in the elderly patients with septic shock were larger than in control group [(55.88±11.18)％ vs.(11.23± 1.82)％].The maximum and minimum radius were positively(r=0.668 and 0.863,both P＜0.01)and RVI negatively(r=-0.848,P＜0.01)with CVP.The thresholds of maximum radius,minimum radius and RVI of IVC to estimate CVP 8 mmHg were 1.56cm(sensitivity 85.2％,specificity 86.3％),1.13 cm(sensitivity 96.3％,specificity 94.1％)and 30％(sensitivity 88.2％,specificity 96.3％),respectively.Conclusions Using ultrasound to measure radius of IVC and calculate RVI might estimate CVP to certain degree.It might be an option for physicians to rapidly estimate blood volume in the elderly patients with septic shock.

Objective To explore the correlation between radius and respiratory variation of inferior vena cava(IVC)and hemodynamic monitoring values of pulse-indicated continuous cardiac output(PiCCO)in septic shock pigs.Methods A total of 8 pigs were used to establish animal model of septic shock by intravenous infusing LPS(100 μg/kg),and fluid resuscitation was followed with normal saline.Ultrasound was used to measure the maximum radius(IVCmax)and minimum radius(IVCmin)of IVC,and respiration variation index(RVI)was calculated at basic status,septic shock,1 hour and 6 hours after fluid resuscitation,respectively.Respiratory variation index of IVC were calculated as:RVI =(IVCmax-IVCmin)/ IVCmax × 100％.Hemodynamic monitoring values,including ITBV,GEDV,SVV and CI of PiCCO,were recorded at the same time.Radius and RVI of IVC and PiCCO values between before and after fluid resuscitation were compared by LSD-t test.Correlation between radius and RVI of IVC andhemodynamic monitoring values were calculated by Pearson correlation coefficient.Results Compared with the moment of septic shock,IVC IVCmin,GEDV,ITBV and CI at 1 after hour fluid resuscitation were larger(P ＜ 0.01)and SVV and IVCrvi were smaller(P ＜ 0.01).Compared with the moment of septic shock and 1 after hour fluid resuscitation,IVC[VCmin,GEDV,[TBV and CI at 6 hours after fluid resuscitation were larger(P ＜ 0.01)and SVV and IVCrvi were smaller(P ＜ 0.01).IVCmax correlated with SVV(P=0.024)and it failed to correlate with GEDV,ITBV and CI.IVCmin correlated with GEDV(P=0.003),ITBV(P =0.001),SVV(P =0.009)and CI(P =0.015),respectively.RVI was correlated withGEDV(P＜0.01),ITBV(P＜0.01),SVV(P=0.007)and CI(P＜0.001),respectively.Conclusions Radius and RVI of IVC was correlated with hemodynamic monitoring values of PiCCO.It can serve as a parameter to rapidly estimate the blood volume.

ObjectiveTo identify the factors influencing the transfer of porcine endogenous retroviruses across the membrane of a new bioartificial liver (BAL),which is a necessary caution to consider for BALs carrying porcine hepatocytes.MethodsA novel porcine BAL composed of two circuits was constructed using a plasma filter with membrane pore size of 500 nm and a plasma component separator with membrane pore sizes 10 nm,20 nm,30 nm,and 35 nm.Co-cultured cells of porcine hepatocytes and mesenchymal stem cells or single porcine hepatocytes were incubated in the bioreactors.The BAL was continuously worked for 72 hours during which the supernatant was collected from the internal and external circuits every 12 hours.PERV RNA,reverse transcriptase (RT) activity,and in vitro infectivity from the supernatant were detected.ResultsIn the plasma filter group,the PERV RNAlevels were the same in both circuits,suggesting little to no effect of the plasma filter on the PERV RNA's crossing.With plasma component separators,PERV RNA was found in the external circuits at different times without positive RT activity and HEK293 cell infection,but its level was reduced significantly.The larger the membrane pore size was,the earlier and the more RNA was detected.ConclusionsThe membrane pore size,the treatment time and the viral level in the internal circuit are contributing factors influencing the transfer of PERV RNA across the membrane in a BAL.

AIM:To investigate the influence of continuous subculturing of human umbilical cord mesenchymal stem cells (hUC-MSCs) on the mRNA expression of all 23 family members of NOD-like receptors (NLRs), and to search for the way of improving the subculture quality of hUC-MSCs and increasing the quantity and safety in the experimental and clinical application .METHODS:Neonatal umbilical cord was collected to isolate and purify the hUC-MSCs with the colla-genase II digestion and adherence screening methods .These cells were continuously subcultured .The hUC-MSCs at pas-sage 3 and passage 28 were identified by flow cytometry and induced differentiation .The mRNA expression of NLRs in the passage 3 and passage 28 hUC-MSCs was detected by RT-qPCR.RESULTS: The cell phenotypes of both passage 3 and passage 28 hUC-MSCs were CD29 +/CD44 +/CD105 +/CD31 -/CD34 -/CD40 -/CD45 -/CD106 -/HLA-DR-, and both of the cells were induced into osteoblasts and adipocytes , which were conformed to the criteria of International Society for Cellular Therapy to define MSCs .All the NLR family members were expressed in passage 3 hUC-MSCs.NOD1, NLRC4, NLRC5, NLRP1, NLRP3, NLRP10, NAIP, NLRX1 and APAF1 at mRNA levels were highly expressed , and the rest were lowly expressed.When hUC-MSCs were subcultured to passage 28, NLRP10 mRNA was increased, NLRC5 mRNA and NLRX1 mRNA were hardly changed , and all of the rest members were decreased .The difference of NLRP1 mRNA expres-sion between passage 3 and passage 28 hUC-MSCs was observed with statistical significance (P<0.05).CONCLU-SION:The effects of subculturing on the expression of NLR family in hUC-MSCs are pleiotropic .It requires further investi-gation to confirm whether these effects are related to the proliferation , differentiation and immunomodulation of MSCs .

Objective As an effective means of liver function support for acute liver failure, bioartificial liver has seen great progress in recent years. However, the development of this type of device is currently hindered by limited oxygen transport to cultured hepatocytes. In this study we try to resolve this problem by supplementing the circulating medium of the bioreactor with red blood cells.Methods Freshly isolated primary porcine hepatocytes were inoculated into our newly designed bioreactor and were divided into two groups: RPMI1640 was circulated in the control group and porcine red blood cells were added into the culture medium in the experimental group. The culture media in both groups were oxygenated through extra-corporeal membrane oxygenation, and the oxygen consumption rate (OCR) in the bioreactor was measured by a blood gas analyzer. Liver-specific functions and glucose consumption were also determined. Results The OCR of the experimental group was 1.5 fold that of the control group, and the glucose consumption rate was twice that of the control group. The liver-specific functions of the experimental group were significantly higher than those of the control group in terrns of albumin secretion and urea synthesis. Conclusion Supplementing the circulating medium of the bioreactor with red blood cells can significantly improve the oxygen supply in the bioreactor, thereby enhancing the glucose consumption and liver-specific functions of hepatocytes. This method is convenient and effective, and is expected to be an effective means to resolve the problems of oxygen supply in the bioreactor.