Prevalence of latent tuberculosis infection among healthcare workers in China as detected by two interferon-gamma release assays

Healthcare workers in China have a high risk of tuberculosis infection. This study measured the prevalence of latent tuberculosis infection in 210 healthcare workers in a chest hospital in Harbin using two interferon-gamma release assays (IGRAs) [QuantiFERON(®)-TB Gold In-Tube (QFT-GIT) and A.TB] and the tuberculin skin test. Results from the IGRAs had moderate agreement with positivity rates of 76.5% (QFT-GIT) and 65.7% (A.TB) but <50% of subjects returned for tuberculin skin test readings. Risk of infection increased with patient exposure. IGRAs may be more useful than tuberculin skin test in monitoring tuberculosis infections in high risk environments.

Effects of retrograde autologous priming on blood transfusion and clinical outcomes in adults: a meta-analysis

Objective:

Reducing the priming volume is an effective means of decreasing hemodilution and blood transfusion during cardiopulmonary bypass (CPB). The patient’s own blood was used to replace the crystalloid in the CPB circuit by retrograde autologous priming (RAP) in order to decrease the priming volume. Therefore, we performed a meta-analysis to investigate whether RAP could reduce blood transfusion and improve clinical outcomes.

Materials and Methods:

A comprehensive search was conducted for randomized, controlled trials (RCTs) exploring RAP in PubMed, Embase, The Cochrane Library, Google Scholar and Chinese literature databases (WanFang, WeiPu and CNKI). Clinical parameters and outcomes were focused on the lowest hematocrit (Hct) during CPB, the number of patients transfused blood intraoperatively, the number of patients transfused blood perioperatively, the number of blood units transfused, 24-hour chest tube drainage, hours to extubation, length of ICU stay, and length of hospital stay.

Results:

Ten trials, with a total of 1123 patients, were included. The number of patients transfused blood intraoperatively (RR = 0.39, 95% CI = [0.29, 0.53], p<0.00001, I2 = 40%) and perioperatively (RR = 0.53, 95% CI = [0.43, 0.66], p<0.00001, I2 = 0%) and the number of blood units transfused (SMD = -0.53, 95% CI = [-0.73, -0.33], p<0.00001, I2 = 14%) were all significantly reduced in the RAP group. No differences in the hours to extubation (SMD = -0.11, 95% CI = [-0.33, 0.12], p=0.37, I2 = 0%) and the length of ICU stay (SMD = -0.17, 95% CI = [-0.41, 0.08], p=0.18, I2 = 0%) were observed between the two groups.

Conclusion:

Compared to conventional priming, RAP could reduce transfusion in adults significantly, but had no effect on clinical outcomes, comparing to conventional priming. Further studies involving RAP are expected to investigate if this technique is beneficial to the patient.

Oncogenic K-Ras requires activation for enhanced activity

Oncogenic Ras mutations are widely considered to be locked in a permanent 'On' state and 'constitutively active'. Yet, many healthy people have cells possessing mutant Ras without apparent harm, and in animal models mutant Ras causes transformation only after upregulation of Ras activity. Here, we demonstrate that oncogenic K-Ras is not constitutively active but can be readily activated by upstream stimulants to lead to prolonged strong Ras activity. These data indicate that in addition to targeting K-Ras downstream effectors, interventions to reduce K-Ras activation may have important cancer-preventive value, especially in patients with oncogenic Ras mutations. As other small G proteins are regulated in a similar manner, this concept is likely to apply broadly to the entire Ras family of molecules.

The effects of zero-balance ultrafiltration on postoperative recovery after cardiopulmonary bypass: a meta-analysis of randomized controlled trials

OBJECTIVE

Considered as a significant ultrafiltration technology during cardiopulmonary bypass (CPB), zero-balance ultrafiltration (Z-BUF) has always received controversial support regarding its effectiveness in reducing inflammatory mediators in plasma. Therefore, we conducted a meta-analysis to evaluate the clinical effect of Z-BUF through screening all relevant published randomized controlled trials (RCTs).

METHODS

A comprehensive search was conducted to screen all RCTs of Z-BUF. Three trained investigators searched databases, including PubMed, Embase, the Cochrane Library, Google scholar, and Chinese literature databases (CNKI, WanFang, WeiPu). RCTs that compared Z-BUF with non-ultrafiltration were included. We focused on clinical outcomes such as length of stay in ICU, duration of ventilation, hospital stay, total amount of chest tube drainage and mortality. Finally, a total of 7 studies containing appropriate criteria were divided into an adult group and a pediatric group. A random effects model was used to calculate weighted mean difference with 95% confidence intervals.

RESULTS

In the adult group, the benefits of Z-BUF in duration of ventilation (WMD=-2.77, 95% CI = [-6.26, 0.72], I(2)=71%, p=0.12) and the length of ICU stay (WMD=-4.13, 95% CI = [-10.09, 1.84], I(2)=77%, Z=1.36, p=0.17) were not apparent, with significant heterogeneity existing in the statistical results. The rest of the clinical parameters could not be evaluated due to insufficient data. In the pediatric group, combined analysis showed Z-BUF could reduce the duration of mechanical ventilation (WMD=3.07; 95%CI= [-7.56, -3.46], I(2)=17%, p=0.27). The advantage of Z-BUF was not observed in other clinical outcomes.

CONCLUSION

The benefits of Z-BUF were not apparent, according to the report. Further studies involving combined ultrafiltration are expected to provide improved ultrafiltration during CPB.

Early changes in cerebral oxidative stress and apoptotic neuronal injury after various flows for selective cerebral perfusion in piglets

BACKGROUND

The impact of various flows for selective cerebral perfusion (SCP) on cerebral oxidative stress in the immature brain is unknown. We examined early changes in cerebral markers of oxidative damage, apoptotic protein activation and histological outcome after different flows for SCP in a piglet model of deep hypothermic circulatory arrest (DHCA).

METHODS

Twenty piglets, randomly divided into four groups (each n = 5), were placed on cardiopulmonary bypass (CPB) at 20°C, then underwent DHCA for 60 minutes. SCP was conducted at flow rates of 0, 25, 50 and 80 ml·kg(-1)·min(-1) through the innominate artery in the DHCA, SCP 25, SCP 50, and SCP 80 groups, respectively. The animals were killed at 2 hours off CPB. Brain tissues were examined for the activity of SOD, MDA and caspase-3, and histological damage was quantitatively assayed by light microscopic examinations.

RESULTS

There were no significant differences in the activities of SOD, MDA and the SOD/MDA index between the groups. Caspase-3 activity significantly decreased in the SCP 25, SCP 50 and SCP 80 groups compared with the DHCA group. However, the caspase-3 level was higher in the SCP 80 group than in the SCP 25 and SCP 50 group. There were no significant correlations between MDA, SOD, SOD/MDA index and caspase-3.

CONCLUSIONS

In this acute model, under different flows for SCP, cerebral MDA and SOD activities show no change, whereas activated caspase-3 has a marked change. There was no relationship between oxidative stress, indicated by MDA and SOD, and apoptotic protein activation in the early phase after DHCA.

Dysfunction of fronto-limbic brain circuitry in depression

BACKGROUND

depression is characterized by a stable negative bias toward emotional stimuli. This bias is associated with abnormal activities in emotion-processing regions (such as the amygdala) and cognitive-control regions (such as the dorsolateral prefrontal cortex [DLPFC]). However, it remains unclear whether the emotion-processing and cognitive-control regions affect negative cognitive bias independently or reciprocally.

EXPERIMENTAL PROCEDURE

a functional magnetic resonance imaging (fMRI) study of 16 depressed patients and 16 matched control subjects was conducted during an emotion-interference task.

RESULTS

the accuracies were significantly lower in the depressed group than in the control group when subjects attended to the happy and the neutral faces. Compared with control participants, depressed patients showed abnormal activity in bilateral amygdala and the right DLPFC. In addition, a significant correlation was found between the right amygdala and the right DLPFC when subjects observed the happy faces.

CONCLUSIONS

the results suggest that the dysfunction in positive emotion-processing and cognitive-control regions may reciprocally affect negative cognitive bias. Additionally, altered positive emotional interference processing in the fronto-limbic brain circuitry might be another cause of negative cognitive bias that finally leads to depression.

Beneficial effects of using a minimal extracorporeal circulation system during coronary artery bypass grafting

Background: In this study, we assessed clinical results by using a minimal extracorporeal circuit (MECC) and compared it to a conventional cardiopulmonary bypass (CPB) system in patients undergoing coronary artery bypass grafting (CABG) procedures.

Methods and Materials: From August to October 2006, forty consecutive patients undergoing isolated CABG procedures were randomly assigned to either a miniaturized closed circuit CPB with the Maquet-Cardiopulmonary MECC system (Group M, n=20) or to a conventional CPB system (Group C, n=20). Clinical outcomes were observed before, during and after the operation. Besides evaluating the perioperative clinical data, serial blood venous samples were obtained after induction, 30 minutes after CPB initiation, 2h, 6h, 12h, and 24h post-CPB. The focus of our study was on myocardial damage (cTnI), neutrophil and platelet counts, activated partial thromboplastin time (aPTT) and free hemoglobin.

Results: Both the transfusion of packed red blood cells and fresh frozen plasma were significantly lower in Group M compared to Group C ( p<0.05). The levels of cTnI were lower in Group M at 2h, 6h and 12h post-CPB than in Group C ( p<0.01). The values of aPTT in Group M recovered to normal levels after surgery, but were prolonged in Group C at early post-CPB and were statistically longer than Group M at 2h, 6h, and 12h post-CPB ( p<0.05). The concentrations of free hemoglobin in Group C were higher than in Group M during and post-CPB, and there was a statistical difference at 2h post-CPB ( p<0.05).

Conclusion: In conclusion, the MECC system is a safe alternative for patients who undertake extracorporeal circulation (ECC) for CABG surgery. Lower transfusion requirements and less damage to red cells may further promote the use of MECC systems, especially in higher risk patients.

Flocculation properties of a bioflocculant produced by Bacillus licheniformis

Studies of the flocculation properties of bioflocculant combined with its structure characterization are helpful to develop more effective bioflocculant. This paper reports findings of our research on the flocculation properties of the bioflocculant ZS-7 in the kaolin suspension based on its structure characterization. With the addition of 2 mg/L ZS-7 and 9 mM CaCl(2), the optimum temperature for flocculation performance of ZS-7 in the kaolin suspension is about 30°C, giving the highest flocculating activity 99.2%. Studies of the flocculation properties revealed that it was stable at 60-100°C and pH 4-10. Moreover, it could flocculate a kaolin suspension over a wide range of pH (2-12) and temperatures (4-95°C) in the presence of CaCl(2).

Effect of cold blood cardioplegia enriched with potassium-magnesium aspartate during coronary artery bypass grafting

AIM

The aim of this investigation is to evaluate the effect of enriched with potassium-magnesium aspartate cold-blood cardioplegia on early reperfusion injury and postoperative arrhythmias in patients with ischemic heart disease undergoing coronary artery bypass grafting (CABG), using measurements of cardiac troponin I (CTnI), hemodynamic indexes and clinical parameters.

METHODS

Forty patients with three-vessel coronary artery disease (CAD) and stable angina, receiving first-time elective CABG, were randomly divided into 2 groups: patients in control group (C group n=20) received routine institutional cold blood cardioplegia (4 degrees C) concentration of Mg2+4 mmol/L, Ca2+1.2 mmol/L and K+ 24mmol/L during myocardial arrest. Patients in P group (n=20) received modified cold blood cardioplegia enriched with potassium-magnesium aspartate and maintained concentration of Mg2+10 mmol/L, Ca2+1.2 mmol/L and K+20mmol/L in the final blood cardioplegia solution. Clinical outcomes were observed during operation and postoperatively. Serial venous blood samples for CTnI were obtained before induction, after cardiopulmonary bypass (CPB), and postoperative 6, 24, and 72 hours. Hemodynamic indexes were obtained before and after bypass by the radial catheter and Swan-Ganz catheter.

RESULTS

In both groups, there were no differences regarding preoperative parameters. There were no cardiac related deaths in either group. The time required to achieve cardioplegic arrest after cardioplegia administration was significantly shorter in P group (47.5+/-16.3 s) than in C group (62.5+/-17.6 s) (P<0.01). The number of patients showing a return to spontaneous rhythm after clamp off was significantly greater in P group (n=20, 100%) than in C group (n=14, 70%) (P<0.01). Eight patients in C group had atrial fibrillation (AF) compared with two patients in P group (P<0.05) in the early of postoperative period. The level of CTnI increased 6 hours and 12 hours postoperatively, and there was a significant difference between groups (P<0.05). P group also shortened the time of postoperative mechanical ventilation (P<0.05) after surgery.

CONCLUSIONS

Cold blood cardioplegia enriched with potassium-magnesium aspartate is beneficial on reducing reperfusion injury.

Cell culture studies of a carborane cholesteryl ester with conventional and PEG liposomes

A new cholesterol-carborane conjugate (BCH) has been synthesized as a potential targeting agent for boron neutron capture therapy (BNCT) of cancers. The compound is extremely water insoluble and was formulated in two liposomal formulations to determine if the compound could be adequately taken up by 9L rat glioma cells in cell culture. Several factors potentially affecting the cellular uptake were evaluated, such as concentration of BCH in the incubation medium, incubation time, cell confluence, and the addition of polyethylene glycol (PEG) phospholipids to the liposomal formulation. The studies indicated that the cellular uptakes of BCH in the conventional and PEG liposomal formulations were 49.1 and 45.9 microg boron/g cells, respectively. Therefore, this compound, formulated in both liposomal formulations, delivered sufficient levels of boron to cancer cells in vitro, indicating that BCH is a promising approach for use in BNCT. The uptake appeared to depend upon BCH concentration in the media as well as the confluence of the cells. The greater boron uptake by nonconfluent cells indicated that active growth of cells was a factor in the uptake of this compound.

Human pancreatic acinar cells lack functional responses to cholecystokinin and gastrin

BACKGROUND & AIMS

Pancreatic acinar cells from various species express cholecystokinin (CCK) A, CCK-B, or a combination of these CCK receptor subtypes. The presence and functional roles of CCK receptors on human acinar cells remain unclear.

METHODS

Acini isolated from human pancreas were treated with CCK receptor agonists, CCK-8 and gastrin, and an agonist for m3 muscarinic acetylcholine receptors (m3 AchR), carbachol. Functional parameters measured included intracellular [Ca(2+)], amylase secretion, and ERK phosphorylation. Binding studies were performed using (125)I-CCK-8. Expression of messenger RNAs (mRNAs) was determined using real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR) and localized by in situ hybridization.

RESULTS

Human acini did not respond to CCK agonists. In contrast, they responded to carbachol with robust increases in each of the functional parameters. Moreover, the cells responded to CCK agonists after adenoviral-mediated gene transfer of CCK-A or CCK-B receptors. A low level of specific and a high level of nonspecific binding of (125)I-CCK-8 were observed. Quantitative RT-PCR indicated that the message levels for CCK-A receptors were approximately 30-fold lower than those of CCK-B receptors, which were approximately 10-fold lower than those of m3 Ach receptors. In situ hybridization indicated the presence of m3 Ach receptor and insulin mRNA but not CCK-A or CCK-B receptor mRNAs in adult human pancreas.

CONCLUSIONS

These data indicate that human pancreatic acinar cells do not respond to CCK receptor agonists in terms of expected functional parameters and show that this is due to an insufficient level of receptor expression.

Effectiveness of once-weekly rifapentine and moxifloxacin regimens against Mycobacterium tuberculosis in mice

Mice infected with 1.6 x 10(7) CFU of Mycobacterium tuberculosis were treated 14 days later for 6 months with a regimen of once-weekly 10 mg of rifapentine and 75 mg of isoniazid per kg of body weight supplemented with either 150 mg of streptomycin per kg or 100 mg of moxifloxacin per kg during either both the 2-week daily initial and once-weekly continuation phases or only in the daily 2-week initial phase. On completion of treatment, all lung cultures were negative, except for three mice, each with a single colony: two whose rifapentine-isoniazid regimen was supplemented with streptomycin during the whole course of therapy and one whose rifapentine-isoniazid regimen had no initial daily phase, but was supplemented with streptomycin and moxifloxacin during the whole course of therapy. After 3 months of follow-up, positive lung cultures were obtained from 61 and 56% of mice supplemented with streptomycin during either the full course of therapy or only the daily 2-week initial phase, respectively, and 15 and 50% of mice supplemented with moxifloxacin during either the full course of therapy or only the daily 2-week initial phase, respectively. These results suggest that moxifloxacin has sterilizing activity against M. tuberculosis.

Glutathione S-transferase genotypes and stomach cancer in a population-based case-control study in Warsaw, Poland

Glutathione S-transferases are important in the detoxification of a wide range of human carcinogens. Previous studies have shown inconsistent associations between the GSTT1 and GSTM1 null genotypes and stomach cancer risk. We investigated the relationship between these and related genotypes and stomach cancer risk in a population-based case-control study in Warsaw, Poland, where stomach cancer incidence and mortality rates are among the highest in Europe. DNA from blood samples was available for 304 stomach cancer patients and 427 control subjects. We observed a 1.48-fold increased risk for stomach cancer (95% confidence interval 0.97-2.25) in patients with the GSTT1 null genotype but no evidence of increased risk associated with the GSTM1, GSTM3 or GSTP1 genotypes. Furthermore, the stomach cancer risk associated with the GSTT1 null genotype varied by age at diagnosis, with odds ratios of 3.85, 1.91, 1.78 and 0.59 for those diagnosed at ages less than 50, 50-59, 60-69 and 70 years or older, respectively (P trend = 0.01). This was due to a shift in the GSTT1 genotype distribution across age groups among stomach cancer patients only. These results suggest that the GSTT1 null genotype may be associated with increased risk of stomach cancer.

Efficacies of clarithromycin regimens against Mycobacterium xenopi in mice

Mice were infected intravenously with 3.5 x 10(7) CFU of Mycobacterium xenopi and treated with various clarithromycin-containing regimens or left untreated for 4 weeks. All nine of the clarithromycin-containing regimens reduced the CFU counts to the levels below the pretreatment values, indicating that these regimens had a bactericidal effect on M. xenopi in mice. The rifampin-isoniazid-ethambutol regimen was significantly less bactericidal than clarithromycin alone or clarithromycin-containing combined regimens.

[Effects of grazing and cultivating on emission of nitrous oxide, carbon dioxide and uptake of methane from grasslands]

Measurement of N2O, CO2 and CH4 with the optimized closed chamber/GC technique in the typical grassland, which were influenced by human activities, grazing and cultivating first time in situ were carried out in Inner Mongolia of P. R. China from 1998 to 1999. It was found that wheat cropping can increase N2O production 3 times than the native, and changed a CO2 sink of Inner Mongolia Steppe to a significant source, increased efflux CO2(C) average 14.3 mg.(m2.h)-1 from Jun. to Dec. in 1998. CH4 uptake was highly increased if there was grazing lightly. There were no effects of wheat cropping on CH4 uptake and no significant results of grazing on N2O emission. Soil moisture and temperature were the key factors, other than human activities, which affect the patterns of seasonal variation of N2O and CO2 emission and CH4 uptake. Highly inter-annual variations, which resulted from the annual precipitation, of the exchange fluxes and seasonal variation patterns of N2O and CO2 emission and CH4 uptake there were. It was a fact that N2O and CO2 emission from the soils was inversely related to CH4 uptake.

[Study on the association of pathologic myopia with HLA-DQB1 gene]

OBJECTIVE

To investigate the association of pathologic myopia (PM) with HLA-DQB1 alleles in order to study the pathogenesis of PM.

METHODS

The genome DNA of 66 patients with PM was extracted from the blood. The second exon of the HLA-DQB1 gene was amplified by polymerase chain reaction (PCR), and individual PCR products were digested by allele specific restriction enzymes of Hae III, BssH II, Apa I, BsaH I, Hae II, Hpa II, Rsa I, Bsp 1286 I for typing. Genotype was determined by restriction fragment length polymorphism (RFLP) pattern. The frequency of 16 alleles of HLA-DQB1 was detected and compared with that of the healthy control.

RESULTS

The frequencies of HLA-DQB1 * 0301 and * 0303 were significantly higher in the patients with PM (P < 0.0001), while that of HLA-DQB1 * 0601 and * 0602 were significantly lower (P < 0.0001) than that of the control group.

CONCLUSION

HLA-DQB1 * 0301, * 0303 alleles are susceptible alleles, and possibly they are the pathogenic genes, * 0601, * 0602 are resistant alleles, and may be they possess the protective property.

A possible mechanism of naproxen-induced lipid peroxidation in rat liver microsomes

Previous papers from our laboratory report that naproxen and salicylic acid induced lipid peroxidation in rat liver microsomes, however, the mechanism is still unclear. In the present paper, ferrous iron release, nicotinamide-adenine dinucleotide phosphate reduced form (NADPH) oxidation and hydrogen peroxide (H2O2) formation have been measured to find out which mechanisms are involved in naproxen- and salicylic acid-induced lipid peroxidation. While the increase of ferrous iron release was observed with high concentrations of naproxen, salicylic acid did not stimulate ferrous iron release. Neither of these drugs stimulated NADPH oxidation and H2O2 formation. However hexobarbital and perfluorohexane, known as uncouplers of cytochrome P450, stimulated microsomal NADPH oxidation, O2 consumption, H2O2 formation and water (H2O) formation involving four-electron oxidase reaction. These results suggest that ferrous iron release contributes to naproxen-induced microsomal lipid peroxidation and that naproxen and salicylic acid are not uncouplers of cytochrome P450. Apparently H2O2 does not play an important role in naproxen- and salicylic acid-induced microsomal lipid peroxidation.

CCK independently activates intracellular trypsinogen and NF-kappaB in rat pancreatic acinar cells

In the cholecystokinin (CCK) hyperstimulation model of acute pancreatitis, two early intracellular events, activation of trypsinogen and activation of nuclear factor-kappaB (NF-kappaB), are thought to be important in the development of the disease. In this study, the relationship between these two events was investigated. NF-kappaB activity was monitored by using a DNA binding assay and mob-1 chemokine gene expression. Intracellular trypsin activity was measured by using a fluorogenic substrate. Protease inhibitors including FUT-175, Pefabloc, and E-64d prevented CCK stimulation of intracellular trypsinogen and NF-kappaB activation. Likewise, the NF-kappaB inhibitors pyrrolidine dithiocarbamate and N-acetyl-L-cysteine inhibited CCK stimulation of NF-kappaB and intracellular trypsinogen activation. These results suggested a possible codependency of these two events. However, CCK stimulated NF-kappaB activation in Chinese hamster ovary-CCK(A) cells, which do not express trypsinogen, indicating that trypsin is not necessary for CCK activation of NF-kappaB. Furthermore, adenovirus-mediated expression in acinar cells of active p65 subunits to stimulate NF-kappaB, or of inhibitory kappaB-alpha molecules to inhibit NF-kappaB, did not affect either basal or CCK-mediated trypsinogen activation. Thus trypsinogen and NF-kappaB activation are independent events stimulated by CCK.