[Analysis of the awareness rate and correlates of core information on tuberculosis prevention and control in elderly in Chinese]

Objective: To understand the awareness and influencing factors of core information on tuberculosis prevention and control in the elderly population in China. Methods: The study included all participants aged ≥60 from the "13th Five-Year" National Tuberculosis Control Plan end-term assessment in 2020, with 13 706 valid questionnaires obtained. Multivariate logistic regression was used to analyze the influencing factors of the awareness rate of core information on tuberculosis prevention and control in the elderly. Results: The total awareness rate of core information on tuberculosis prevention and control in the elderly aged ≥60 was 78.4%, with the highest for "suspicious symptoms of pulmonary tuberculosis" (85.4%) and the lowest for "whether pulmonary tuberculosis can be cured" (65.3%). The complete awareness rate of core information on tuberculosis prevention and control in the elderly was 41.3%, and the proportion of those who received tuberculosis health education is 67.6%. Multivariate logistic regression analysis results showed that factors associated with low awareness of core information included females (OR=0.93, 95%CI: 0.86-1.00), ages 70- (OR=0.91, 95%CI: 0.84-0.98) and ≥80 (OR=0.77, 95%CI: 0.68-0.87) and minority ethnicity (OR=0.85, 95%CI: 0.74-0.99). Factors associated with high awareness of core information included educational levels of junior high school (OR=1.46, 95%CI: 1.34-1.58), high school (OR=1.62, 95%CI: 1.45-1.81), junior college (OR=1.37, 95%CI: 1.11-1.68), and an undergraduate degree or higher (OR=1.52, 95%CI: 1.09-2.11), and receiving tuberculosis health education (OR=2.13, 95%CI: 1.97-2.27). Conclusions: In 2020, the awareness rate of core information on tuberculosis prevention and control in Chinese older adults aged ≥60 was lower than the national planning target. Therefore, there should be an increased focus on health education about tuberculosis for elderly females, those aged ≥70, ethnic minorities, and those with lower education levels.

Singlet oxygen induces cell wall thickening and stomatal density reducing by transcriptome reprogramming

Singlet oxygen (1O2) has a very short half-life of 10-5 s; however, it is a strong oxidant that causes growth arrest and necrotic lesions on plants. Its signaling pathway remains largely unknown. The Arabidopsis flu (fluorescent) mutant accumulates a high level of 1O2 and shows drastic changes in nuclear gene expression. Only two plastid proteins, EX1 (executer 1) and EX2 (executer 2), have been identified in the singlet oxygen signaling. Here, we found that the transcription factor abscisic acid insensitive 4 (ABI4) binds the promoters of genes responsive to 1O2-signals. Inactivation of the ABI4 protein in the flu/abi4 double mutant was sufficient to compromise the changes of almost all 1O2-responsive-genes and rescued the lethal phenotype of flu grown under light/dark cycles, similar to the flu/ex1/ex2 triple mutant. In addition to cell death, we reported for the first time that 1O2 also induces cell wall thickening and stomatal development defect. Contrastingly, no apparent growth arrest was observed for the flu mutant under normal light/dim light cycles, but the cell wall thickening (doubled) and stomatal density reduction (by two-thirds) still occurred. These results offer a new idea for breeding stress tolerant plants.

Hyperon Polarization along the Beam Direction Relative to the Second and Third Harmonic Event Planes in Isobar Collisions at sqrt[s_{NN}]=200 GeV

The polarization of Λ and Λ[over ¯] hyperons along the beam direction has been measured relative to the second and third harmonic event planes in isobar Ru+Ru and Zr+Zr collisions at sqrt[s_{NN}]=200  GeV. This is the first experimental evidence of the hyperon polarization by the triangular flow originating from the initial density fluctuations. The amplitudes of the sine modulation for the second and third harmonic results are comparable in magnitude, increase from central to peripheral collisions, and show a mild p_{T} dependence. The azimuthal angle dependence of the polarization follows the vorticity pattern expected due to elliptic and triangular anisotropic flow, and qualitatively disagrees with most hydrodynamic model calculations based on thermal vorticity and shear induced contributions. The model results based on one of existing implementations of the shear contribution lead to a correct azimuthal angle dependence, but predict centrality and p_{T} dependence that still disagree with experimental measurements. Thus, our results provide stringent constraints on the thermal vorticity and shear-induced contributions to hyperon polarization. Comparison to previous measurements at RHIC and the LHC for the second-order harmonic results shows little dependence on the collision system size and collision energy.

Measurements of the Elliptic and Triangular Azimuthal Anisotropies in Central ^{3}He+Au, d+Au and p+Au Collisions at sqrt[s_{NN}]=200 GeV

The elliptic (v_{2}) and triangular (v_{3}) azimuthal anisotropy coefficients in central ^{3}He+Au, d+Au, and p+Au collisions at sqrt[s_{NN}]=200  GeV are measured as a function of transverse momentum (p_{T}) at midrapidity (|η|<0.9), via the azimuthal angular correlation between two particles both at |η|<0.9. While the v_{2}(p_{T}) values depend on the colliding systems, the v_{3}(p_{T}) values are system independent within the uncertainties, suggesting an influence on eccentricity from subnucleonic fluctuations in these small-sized systems. These results also provide stringent constraints for the hydrodynamic modeling of these systems.

Observation of Directed Flow of Hypernuclei _{Λ}^{3}H and _{Λ}^{4}H in sqrt[s_{NN}]=3 GeV Au+Au Collisions at RHIC

We report here the first observation of directed flow (v_{1}) of the hypernuclei _{Λ}^{3}H and _{Λ}^{4}H in mid-central Au+Au collisions at sqrt[s_{NN}]=3  GeV at RHIC. These data are taken as part of the beam energy scan program carried out by the STAR experiment. From 165×10^{6} events in 5%-40% centrality, about 8400 _{Λ}^{3}H and 5200 _{Λ}^{4}H candidates are reconstructed through two- and three-body decay channels. We observe that these hypernuclei exhibit significant directed flow. Comparing to that of light nuclei, it is found that the midrapidity v_{1} slopes of _{Λ}^{3}H and _{Λ}^{4}H follow baryon number scaling, implying that the coalescence is the dominant mechanism for these hypernuclei production in the 3 GeV Au+Au collisions.

Beam Energy Dependence of Triton Production and Yield Ratio (N_{t}×N_{p}/N_{d}^{2}) in Au+Au Collisions at RHIC

We report the triton (t) production in midrapidity (|y|<0.5) Au+Au collisions at sqrt[s_{NN}]=7.7-200  GeV measured by the STAR experiment from the first phase of the beam energy scan at the Relativistic Heavy Ion Collider. The nuclear compound yield ratio (N_{t}×N_{p}/N_{d}^{2}), which is predicted to be sensitive to the fluctuation of local neutron density, is observed to decrease monotonically with increasing charged-particle multiplicity (dN_{ch}/dη) and follows a scaling behavior. The dN_{ch}/dη dependence of the yield ratio is compared to calculations from coalescence and thermal models. Enhancements in the yield ratios relative to the coalescence baseline are observed in the 0%-10% most central collisions at 19.6 and 27 GeV, with a significance of 2.3σ and 3.4σ, respectively, giving a combined significance of 4.1σ. The enhancements are not observed in peripheral collisions or model calculations without critical fluctuation, and decreases with a smaller p_{T} acceptance. The physics implications of these results on the QCD phase structure and the production mechanism of light nuclei in heavy-ion collisions are discussed.

ABO blood groups and nosocomial infection

The timely identification of the high-risk groups for nosocomial infections (NIs) plays a vital role in its prevention and control. Therefore, it is crucial to investigate whether the ABO blood group is a risk factor for NI. In this study, patients with NI and non-infection were matched by the propensity score matching method and a logistic regression model was used to analyse the matched datasets. The study found that patients with the B&AB blood group were susceptible to Escherichia coli (OR = 1.783, p = 0.039); the A blood group were susceptible to Staphylococcus aureus (OR = 2.539, p = 0.019) and Pseudomonas aeruginosa (OR = 5.724, p = 0.003); the A&AB blood group were susceptible to Pseudomonas aeruginosa (OR = 4.061, p = 0.008); the AB blood group were vulnerable to urinary tract infection (OR = 13.672, p = 0.019); the B blood group were susceptible to skin and soft tissue infection (OR = 2.418, p = 0.016); and the B&AB blood group were vulnerable to deep incision infection (OR = 4.243, p = 0.043). Summarily, the patient's blood group is vital for identifying high-risk groups for NIs and developing targeted prevention and control measures for NIs.

Measurement of Sequential ϒ Suppression in Au+Au Collisions at sqrt[s_{NN}]=200 GeV with the STAR Experiment

We report on measurements of sequential ϒ suppression in Au+Au collisions at sqrt[s_{NN}]=200  GeV with the STAR detector at the Relativistic Heavy Ion Collider (RHIC) through both the dielectron and dimuon decay channels. In the 0%-60% centrality class, the nuclear modification factors (R_{AA}), which quantify the level of yield suppression in heavy-ion collisions compared to p+p collisions, for ϒ(1S) and ϒ(2S) are 0.40±0.03(stat)±0.03(sys)±0.09(norm) and 0.26±0.08(stat)±0.02(sys)±0.06(norm), respectively, while the upper limit of the ϒ(3S) R_{AA} is 0.17 at a 95% confidence level. This provides experimental evidence that the ϒ(3S) is significantly more suppressed than the ϒ(1S) at RHIC. The level of suppression for ϒ(1S) is comparable to that observed at the much higher collision energy at the Large Hadron Collider. These results point to the creation of a medium at RHIC whose temperature is sufficiently high to strongly suppress excited ϒ states.

Beam Energy Dependence of Fifth- and Sixth-Order Net-Proton Number Fluctuations in Au+Au Collisions at RHIC

We report the beam energy and collision centrality dependence of fifth and sixth order cumulants (C_{5}, C_{6}) and factorial cumulants (κ_{5}, κ_{6}) of net-proton and proton number distributions, from center-of-mass energy (sqrt[s_{NN}]) 3 GeV to 200 GeV Au+Au collisions at RHIC. Cumulant ratios of net-proton (taken as proxy for net-baryon) distributions generally follow the hierarchy expected from QCD thermodynamics, except for the case of collisions at 3 GeV. The measured values of C_{6}/C_{2} for 0%-40% centrality collisions show progressively negative trend with decreasing energy, while it is positive for the lowest energy studied. These observed negative signs are consistent with QCD calculations (for baryon chemical potential, μ_{B}≤110  MeV) which contains the crossover transition range. In addition, for energies above 7.7 GeV, the measured proton κ_{n}, within uncertainties, does not support the two-component (Poisson+binomial) shape of proton number distributions that would be expected from a first-order phase transition. Taken in combination, the hyperorder proton number fluctuations suggest that the structure of QCD matter at high baryon density, μ_{B}∼750  MeV at sqrt[s_{NN}]=3  GeV is starkly different from those at vanishing μ_{B}∼24  MeV at sqrt[s_{NN}]=200  GeV and higher collision energies.

Collision-System and Beam-Energy Dependence of Anisotropic Flow Fluctuations

Elliptic flow measurements from two-, four-, and six-particle correlations are used to investigate flow fluctuations in collisions of U+U at sqrt[s_{NN}]=193  GeV, Cu+Au at sqrt[s_{NN}]=200  GeV and Au+Au spanning the range sqrt[s_{NN}]=11.5-200  GeV. The measurements show a strong dependence of the flow fluctuations on collision centrality, a modest dependence on system size, and very little if any, dependence on particle species and beam energy. The results, when compared to similar LHC measurements, viscous hydrodynamic calculations, and trento model eccentricities, indicate that initial-state-driven fluctuations predominate the flow fluctuations generated in the collisions studied.

Evidence for Nonlinear Gluon Effects in QCD and Their Mass Number Dependence at STAR

The STAR Collaboration reports measurements of back-to-back azimuthal correlations of di-π^{0}s produced at forward pseudorapidities (2.6<η<4.0) in p+p, p+Al, and p+Au collisions at a center-of-mass energy of 200 GeV. We observe a clear suppression of the correlated yields of back-to-back π^{0} pairs in p+Al and p+Au collisions compared to the p+p data. The observed suppression of back-to-back pairs as a function of transverse momentum suggests nonlinear gluon dynamics arising at high parton densities. The larger suppression found in p+Au relative to p+Al collisions exhibits a dependence of the saturation scale Q_{s}^{2} on the mass number A. A linear scaling of the suppression with A^{1/3} is observed with a slope of -0.09±0.01.

Measurements of Proton High-Order Cumulants in sqrt[s_{NN}]=3 GeV Au+Au Collisions and Implications for the QCD Critical Point

We report cumulants of the proton multiplicity distribution from dedicated fixed-target Au+Au collisions at sqrt[s_{NN}]=3.0  GeV, measured by the STAR experiment in the kinematic acceptance of rapidity (y) and transverse momentum (p_{T}) within -0.5<y<0 and 0.4<p_{T}<2.0  GeV/c. In the most central 0%-5% collisions, a proton cumulant ratio is measured to be C_{4}/C_{2}=-0.85±0.09 (stat)±0.82 (syst), which is 2σ below the Poisson baseline with respect to both the statistical and systematic uncertainties. The hadronic transport UrQMD model reproduces our C_{4}/C_{2} in the measured acceptance. Compared to higher energy results and the transport model calculations, the suppression in C_{4}/C_{2} is consistent with fluctuations driven by baryon number conservation and indicates an energy regime dominated by hadronic interactions. These data imply that the QCD critical region, if created in heavy-ion collisions, could only exist at energies higher than 3 GeV.

Measurements of _{Λ}^{3}H and _{Λ}^{4}H Lifetimes and Yields in Au+Au Collisions in the High Baryon Density Region

We report precision measurements of hypernuclei _{Λ}^{3}H and _{Λ}^{4}H lifetimes obtained from Au+Au collisions at sqrt[s_{NN}]=3.0  GeV and 7.2 GeV collected by the STAR experiment at the Relativistic Heavy Ion Collider, and the first measurement of _{Λ}^{3}H and _{Λ}^{4}H midrapidity yields in Au+Au collisions at sqrt[s_{NN}]=3.0  GeV. _{Λ}^{3}H and _{Λ}^{4}H, being the two simplest bound states composed of hyperons and nucleons, are cornerstones in the field of hypernuclear physics. Their lifetimes are measured to be 221±15(stat)±19(syst)  ps for _{Λ}^{3}H and 218±6(stat)±13(syst)  ps for _{Λ}^{4}H. The p_{T}-integrated yields of _{Λ}^{3}H and _{Λ}^{4}H are presented in different centrality and rapidity intervals. It is observed that the shape of the rapidity distribution of _{Λ}^{4}H is different for 0%-10% and 10%-50% centrality collisions. Thermal model calculations, using the canonical ensemble for strangeness, describes the _{Λ}^{3}H yield well, while underestimating the _{Λ}^{4}H yield. Transport models, combining baryonic mean-field and coalescence (jam) or utilizing dynamical cluster formation via baryonic interactions (phqmd) for light nuclei and hypernuclei production, approximately describe the measured _{Λ}^{3}H and _{Λ}^{4}H yields. Our measurements provide means to precisely assess our understanding of the fundamental baryonic interactions with strange quarks, which can impact our understanding of more complicated systems involving hyperons, such as the interior of neutron stars or exotic hypernuclei.

Probing the Gluonic Structure of the Deuteron with J/ψ Photoproduction in d+Au Ultraperipheral Collisions

Understanding gluon density distributions and how they are modified in nuclei are among the most important goals in nuclear physics. In recent years, diffractive vector meson production measured in ultraperipheral collisions (UPCs) at heavy-ion colliders has provided a new tool for probing the gluon density. In this Letter, we report the first measurement of J/ψ photoproduction off the deuteron in UPCs at the center-of-mass energy sqrt[s_{NN}]=200  GeV in d+Au collisions. The differential cross section as a function of momentum transfer -t is measured. In addition, data with a neutron tagged in the deuteron-going zero-degree calorimeter is investigated for the first time, which is found to be consistent with the expectation of incoherent diffractive scattering at low momentum transfer. Theoretical predictions based on the color glass condensate saturation model and the leading twist approximation nuclear shadowing model are compared with the data quantitatively. A better agreement with the saturation model has been observed. With the current measurement, the results are found to be directly sensitive to the gluon density distribution of the deuteron and the deuteron breakup process, which provides insights into the nuclear gluonic structure.

Modeling the early transmission of COVID-19 in New York and San Francisco using a pairwise network model

Classical epidemiological models assume mass action. However, this assumption is violated when interactions are not random. With the recent COVID-19 pandemic, and resulting shelter in place social distancing directives, mass action models must be modified to account for limited social interactions. In this paper we apply a pairwise network model with moment closure to study the early transmission of COVID-19 in New York and San Francisco and to investigate the factors determining the severity and duration of outbreak in these two cities. In particular, we consider the role of population density, transmission rates and social distancing on the disease dynamics and outcomes. Sensitivity analysis shows that there is a strongly negative correlation between the clustering coefficient in the pairwise model and the basic reproduction number and the effective reproduction number. The shelter in place policy makes the clustering coefficient increase thereby reducing the basic reproduction number and the effective reproduction number. By switching population densities in New York and San Francisco we demonstrate how the outbreak would progress if New York had the same density as San Francisco and vice-versa. The results underscore the crucial role that population density has in the epidemic outcomes. We also show that under the assumption of no further changes in policy or transmission dynamics not lifting the shelter in place policy would have little effect on final outbreak size in New York, but would reduce the final size in San Francisco by 97%.

The influence of mask use on the spread of COVID-19 during pandemic in New York City

In New York City, the situation of COVID-19 is so serious that it has caused hundreds of thousands of people to be infected due to its strong infectivity. The desired effect of wearing masks by the public is not ideal, though increasingly recommended by the WHO. In order to reveal the potential effect of mask use, we posed a dynamical model with the effective coverage of wearing face masks to assess the impact of mask use on the COVID-19 transmission. We obtained the basic reproduction number  R 0 which determined the global dynamics. According to the implement of policies in New York City, we divided the transmission of COVID-19 in three stages. Based on mathematical model and data, we obtain the mean value  R 0 = 1 . 822 in the first stage of New York City, while  R 0 = 0 . 6483 in the second stage due to that the US Centers for Disease Control and Prevention (CDC) recommended the public wear masks on April 3, 2020,  R 0 = 1 . 024 in the third stage after reopening. It was found that if the effective coverage rate of mask use  α exceed a certain value  α c = 0 . 182 , COVID-19 can be well controlled in the second stage of New York City. Additionally, when the effective coverage of masks reaches a certain level  α = 0 . 5 , the benefits are not obvious with the increased coverage rate compared to the cost of medical resources. Moreover, if the effective coverage of mask use in public reaches 20% in the first stage, then the cumulative confirmed cases will be reduced about 50% by 03 April, 2020. Our results demonstrated a new insight on the effect of mask use in controlling the transmission of COVID-19.

The Impact of Quarantine and Medical Resources on the Control of COVID-19 in Wuhan based on a Household Model

In order to understand how Wuhan curbed the COVID-19 outbreak in 2020, we build a network transmission model of 123 dimensions incorporating the impact of quarantine and medical resources as well as household transmission. Using our new model, the final infection size of Wuhan is predicted to be 50,662 (95%CI: 46,234, 55,493), and the epidemic would last until April 25 (95%CI: April 23, April 29), which are consistent with the actual situation. It is shown that quarantining close contacts greatly reduces the final size and shorten the epidemic duration. The opening of Fangcang shelter hospitals reduces the final size by about 17,000. Had the number of hospital beds been sufficient when the lockdown started, the number of deaths would have been reduced by at least 54.26%. We also investigate the distribution of infectious individuals in unquarantined households of different sizes. The high-risk households are those with size from two to four before the peak time, while the households with only one member have the highest risk after the peak time. Our findings provide a reference for the prevention, mitigation and control of COVID-19 in other cities of the world.

[A Meta-analysis on varicella-zoster virus antibody levels in healthy population in China]

Objective: To systematically analyze and evaluate the IgG antibody levels of varicella-zoster virus (VZV) in healthy population in China. Methods: CNKI, Wanfang, CBM and PubMed databases were used for the retrieval of literatures about VZV IgG antibody levels in healthy people in China from January 1, 2000 to November 3, 2020. The quality of the included papers was evaluated by the critical appraisal tools for cross sectional study from Joanna Briggs Institute (JBL). The stratified analysis on the IgG antibody levels in populations in different age groups, provinces, regions, gender groups, and years was performed by using software Stata 14.0. Results: A total of 59 papers were included that met the inclusion criteria, including 51 papers in Chinese and 8 papers in English. There were 22 papers with quality score of 8, 16 papers with quality score of 7, 15 papers with quality score of 6, and 6 papers with quality score of 5. Meta-analysis showed that the positive rate of VZV IgG antibody in healthy population in China was 64% (95%CI:60%-67%, I² =98.7%), and the IgG antibody levels were reported in the papers for 22 provinces of China. The positive rate of VZV IgG antibody was highest in Yunnan (79%, 95%CI: 64%-93%, I² =94.7%) and lowest in Inner Mongolia (50%, 95%CI: 46%-54%); the positive rate of VZV IgG antibody was highest in Northeastern China (71%, 95%CI: 69%-73%) and lowest in Eastern China (62%, 95%CI: 57%-67%); the positive rate of VZV IgG antibody in urban population was higher than that in rural population (RR=1.08, 95%CI: 1.04-1.11). The positive rate of VZV IgG antibody in women was higher than that in men (RR=1.10, 95%CI: 1.08-1.11); the positive rate of VZV IgG antibody in the population increased with age; and the positive rate of VZV IgG antibody increased with the change of sampling time. Conclusion: The positive rate of VZV IgG antibody in healthy population in China was relatively low; the coverage of varicella vaccine should be improved for the outbreak control and incidence reduction of varicella in China.

[Clinical characteristics and prognostic risk factors analysis of carbapenem-resistant organism in the department of hematology]

Objective: To study the distribution and drug resistance of Carbapenem-Resistant Organism (CRO) and to analysis the risk factors of CRO 30-day mortality. Methods: A total of 181 patients with CRO infection diagnosed in Department of Hematology, Fujian Medical University Union Hospital from January 2018 to June 2020 were retrospectively investigated. The clinical and laboratory data of the patients were collected, the prognosis of patients diagnosed with CRO infection in day 30 was followed up, and the risk factors of prognosis were analyzed. The clinical significance of Carbapenem-Resistant Enterobacteriaceae (CRE) active screening was further evaluated in the CRE subgroup. Results: Among the total of 181 CRO isolates, 47.2% were CRE, 37.0% were Pseudomonas aeruginosa, and 32.6% were Klebsiella pneumoniae, which were highly resistant to carbapenem and had high MIC value, 76.8% (139/181) of CRO were MIC of imipenem resistance≥16 μg/ml. The main sources of isolates were blood and sputum. The 30-day all-cause mortality rates of patients with CRO or CRE infection were (41.4±3.7) % and (44.7±5.4) %, respectively. The COX multivariate regression analysis showed that the level of procalcitonin >0.2 ng/ml and the MIC value of imipenem resistance ≥ 16 μg/ml were independent risk factors for 30-day mortality of CRO infected patients. The CRE subgroup analysis showed that MIC value of imipenem resistance ≥16 μg/ml were independent risk factors for 30-day mortality of CRE infected patients. The 30-day cumulative survival rate of patients with CRE active screening was higher than the patients without CRE active screening [ (68.0±9.3) % vs (50.0±6.5) %, P=0.21]. Conclusion: The high MIC value of imipenem resistance isolates seriously affects the prognosis of patients with CRO infection in the hematology department, and the mortality rate was high. CRE active screening is expected for early prevention, early diagnosis, and early treatment for high-risk patients.

A lysosome-targetable two-photon excited near-infrared fluorescent probe for visualizing hypochlorous acid-involved arthritis and its treatment

Lysosome of phagocyte is the main site of hypochlorous acid (HClO) production, and HClO can be employed as the biomarker for the diagnosis and treatment evaluation of arthritis. In recent years, developing fluorescent probes for lysosomal HClO has attracted considerable attention, but most of them still have some defects, such as autofluorescence, phototoxicity and photobleaching because of their excitation and emission located in short-wavelength region. Due to the advantages of two-photon fluorescent probes with near-infrared emissions, a lysosome-targetable two-photon fluorescent probe (Lyso-TP-HClO) with a near-infrared emission was reported in this paper. Lyso-TP-HClO has a high selectivity and a high sensitivity to HClO in the linear range (10.0 × 10^-8 to 5.0 × 10^-6 M), with a detection limit of 3.0 × 10^-8 M. Due to the two-photon excited near-infrared emission, Lyso-TP-HClO has excellent imaging performances, such as small autofluorescence, excellent photostability, and large imaging depth. Furthermore, Lyso-TP-HClO was successfully employed for visualizing lysosomal HClO in bacteria-infected cells. At last, we have successfully used Lyso-TP-HClO to image the arthritis and evaluate the treatment of arthritis in mice. All the results confirm that Lyso-TP-HClO is a useful chemical tool for imaging of lysosomal HClO, the diagnosis of arthritis, and treatment evaluation of arthritis.

Comparison of two electronic hand hygiene monitoring systems in promoting hand hygiene of healthcare workers in the intensive care unit

Background

Hand hygiene (HH) is the cornerstone of infection control, and the promotion of HH is the focus of the world. The study aims to compare the role of two different types of electronic hand hygiene monitoring systems (EHHMSs) in promoting HH of healthcare workers (HCWs) in the intensive care unit (ICU).

Methods

In a 16-bed ICU of a general tertiary hospital in Shenzhen, the research was divided into three stages with interrupted time series (ITS) design. In the first stage, the direct observation method was used to monitor and feed back the HH compliance rate of HCWs monthly. In the second stage, the type1 EHHMS was applied to monitor and feed back the individual number of HH events monthly. In the third stage, the type2 EHHMS with a function of instant reminder and feedback was employed, and the personal HH compliance rates were fed back monthly. Meanwhile, direct observation continued in the last two stages.

Results

In the second stage, The HH compliance rate increased. However, there was no significant difference in the trajectory of the rate compared with the first stage. In the first month of the third stage, the HH compliance rate increased by 12.324% immediately and then ascended by 1.242% over time. The number of HH events per bed day and HH products’ consumption per bed day were consistent with the change of HH compliance rate observed.

Conclusion

Monitoring and feedback can improve the HH of HCWs. The EHHMS, with the function of real-time reminders and feedback, has a more noticeable effect on promoting HH.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-020-05748-3.

Impact of a quality control circle on the incidence of catheter-associated urinary tract infection: An interrupted time series analysis

BACKGROUND

To report a quality control circle (QCC) activity on the theme of reducing the incidence of catheter-associated urinary tract infection (CAUTI), and used an interrupted time series analysis to evaluate the impact of the QCC.

METHODS

In a general tertiary hospital in Shenzhen, China, we carried out a QCC activity with the theme of reducing CAUTI from April 2017 to December 2017. Before the QCC, we carried out the routine measures; during the QCC, we implemented usual measures and the countermeasures of QCC, and after the QCC, we performed the routine measures and adhered to the core measures of QCC. The interrupted time series analysis method was used to analyze the changes in the CAUTI incidence during the 3 stages.

RESULTS

Before, during, and after the QCC activities, the catheter use ratios and mean indwelling time both had a downward trend; meanwhile, the compliance rate of CAUTI prevention measures showed an upward trend. After the interventions, the CAUTI incidence decreased by 1.317‰ immediately, then gradually decreased by 0.510‰ per month. After the completion of QCC, the CAUTI incidence increased by 0.266‰ immediately and increased by 0.070‰ over time, but the difference was not statistically significant.

CONCLUSIONS

The CAUTI incidence is reduced through QCC, providing a useful reference for the prevention of CAUTI and the development of medical quality improvement activities.

Iron overload as a risk factor for poor graft function following allogeneic hematopoietic stem cell transplantation

Hematological malignancies are increasingly treated with allogeneic hematopoietic stem cell transplantation (allo-HSCT). Unfortunately, iron overload is a frequent adverse effect of allo-HSCT and is associated with poor prognosis. In the present study, we investigated hematopoiesis in iron-overloaded mice and elucidated the effects of iron overload on the bone marrow (BM) microenvironment. Iron-overloaded BALB/C mice were generated by injecting 20 mg/mL saccharated iron oxide intraperitoneally. Hematoxylin-eosin staining was performed to evaluate the effects of an iron overload in mice. BM cells obtained from C57BL/6 mice were transplanted into irradiated BALB/C mice (whole-body irradiation of 4 Gy, twice with a 4-hours interval) by tail vein injection. Two weeks after allo-HSCT, the hematopoietic reconstitution capacity was evaluated in recipients by colony-forming assays. Histopathological examinations showed brown-stained granular deposits, irregularly arranged lymphocytes in the liver tissues, and blue-stained blocks in the BM collected from mice received injections of high-dose saccharated iron oxide (20 mg/mL). Iron-overloaded mice showed more platelets, higher-hemoglobin (HGB) concentration, fewer granulocyte-macrophage colony-forming units (CFU-GM), erythrocyte colony-forming units (CFU-E), and mixed granulocyte/erythrocyte/monocyte/megakaryocyte colony-forming units (CFU-mix) than healthy mice. Iron-overloaded recipients presented with reduced erythrocytes and HGB concentration in peripheral blood, along with decreased marrow stroma cells, CFU-GM, CFU-E, and CFU-mix relative to healthy recipients. Taken together, our findings demonstrate that iron overload might alter the number of red blood cells after transplantation in mice by destroying the BM microenvironment, thereby affecting the recovery of BM hematopoietic function.

[Effect of using scenario infiltration joint interactive training mode for junior nurse training in the prevention and treatment of pressure sore]

Objective: To explore the application effect of scenario infiltration joint interactive training mode for junior nurse training in the prevention and treatment of pressure sore. Methods: A total of 118 junior nurses starting to work in the First Affiliated Hospital of Air Force Medical University from July 2017 to July 2018 met the inclusion criteria and were divided into routine training (RT) group and scenario infiltration joint interactive training (SIJIT) group using the random number table for prospective randomized controlled trial. There were 2 males and 57 females, aged (23.9±1.2) years in RT group and 3 males and 56 females, aged (23.5±1.3) years in SIJIT group. Before the training, nurses in both groups received theory and practical tests for the prevention and treatment of pressure sore with a homemade theory test paper and operation requirements designed by the training group. The training content was drawn up in 3 themes according to the weak points shown in the test. Nurses in RT group were trained in a large classroom with the help of multimedia teaching technique, and one lesson of 2 h targeting one theme was given once a week.Nurses in SIJIT group were trained by using the SIJIT mode, with online self-study for 2 weeks and then multimedia theory and practical teaching, and interaction in scene. After the training, theoretical and practical tests were conducted again in nurses of two groups. Satisfaction scores of nurses for the training mode, training effect, and curriculum design and answers to open questions about the degree of training satisfaction were investigated through homemade questionnaire for satisfaction degree. Homemade training contents and requirements questionnaire designed by the training group was used to understand the demands of nurses for training contents and requirements in 2 groups. Data were statistically analyzed with chi-square test and independent sample t test. Results: (1) The theoretical and practical scores on the prevention and treatment of pressure sore before the training were (78±11) and (83±10) points respectively in RT group, similar to (79±11) and (84±10) points in SIJIT group (t=0.522, 0.615, P>0.05). The theoretical and operational scores on prevention and treatment of pressure score of nurses after the training were (90±8) and (92±5) points in SIJIT group, significantly higher than (82±10) and (85±9) points in RT group (t=4.581, 5.259, P<0.01). (2) The satisfaction degree scores for training mode, curriculum design, and training effect of nurses in SIJIT group were significantly higher than those in RT group (t=5.169, 7.976, 4.463, P<0.01). Nurses in the 2 groups were satisfied with the curriculum content, and unsatisfied with the curriculum time and the ways of test. (3) The top demand of the training nurses for curriculum content was the treatment of phase Ⅱ-Ⅲ pressure sore, accounting for 81.36% (96/118). Conclusions: The SIJIT has flexible training mode, and reasonable curriculum design and content, which significantly improves the theoretical and operational levels on prevention and treatment of pressure sore of the training nurses and receives recognition of the training nurses.

[Design of a multifunctional urine bag]

At present, there are many monitoring devices for vital signs parameters for clinical selection, but urine monitoring has not received enough attention. The traditional manual visual measurement, intermittent measurement of urine pH value, and other methods are still in use, so the authors designed a multifunctional urine bag. The urine bag can set up an alarm system per unit time according to patient's age and condition as well as set up urine pH value detection area in hard plastic measuring bottle. This device can not only accurately monitor urine volume per unit time, but also hopefully realize the alarm automation of abnormal urine volume per unit time, as well as real-time dynamic monitoring of urine pH value. It is helpful for medical staff to make accurate judgment on patients' condition changes, to guide the formulation and modification of clinical treatment plans, and to reduce the workload of clinical nursing staff to a certain extent.

[Application of stretched exponential diffusion-weighted imaging model in quantitative diagnosis of nonalcoholic fatty liver disease: in a rabbit model]

Objective: To evaluate the feasibility of diffusion parameters obtained from mono-exponential and stretched exponential diffusion-weighted imaging models in staging of nonalcoholic fatty liver disease and compare the diagnosis ability of nonalcoholic steatohepatitis. Methods: Thirty-two 12 -week-old male New Zealand rabbits, about 2.5 kg of each, were randomly divided into five groups. To obtained different severity groups of NAFLD, a variety of diet (from standard to high-fat, high cholesterol chow) were feed for different periods before liver diffusion imaging was performed by using 3.0 T MR imaging system (Discovery 750W GE health care), the value of ADC, stretched exponential model parameters distributed diffusion coefficient (DDC) and α (water molecular diffusion heterogeneity index) were measured. Liver specimens were obtained for pathological grading (NAFLD activity scoring system). The diffusion parameters of each group of NAFLD were compared by ANOVA, LSD-t test was utilized to pairwise comparison between different grades of NAFLD. Spearman rank correlation analysis was used to evaluate the correlation between ADC, DDC, α and different severity groups of NAFLD. ROC curve was compared to evaluate the diagnostic efficiency of MR parameters for NASH. Results: α was significant different between borderline and NASH groups (0.65±0.05 vs 0.72±0.07; P<0.05); ADC and DDC showed no statistical difference between borderline and NASH groups (ADC:(1.09±0.14)×10(-3) vs (1.04±0.24)×10(-3) mm(2)/s; DDC: (0.73±0.08)×10(-3) vs (0.66±0.19)×10(-3) mm(2)/s; P>0.05); ADC and DDC were negatively correlated with NAFLD, and the correlation coefficients were -0.552, -0.596, respectively (P<0.05). α was found to be positively correlated with advancement of NAFLD, the correlation coefficient was 0.729 (P<0.05).In terms of the diagnostic efficiency of NASH, the AUC of ADC, DDC and α were 0.736, 0.784, 0.900, respectively, α was significantly greater than ADC in diagnosis of NASH (P<0.05). Conclusion: Stretched exponential model parameter α (water molecular diffusion heterogeneity index) could be utilized to identify NAFLD. α may provide more information and improve the staging of NASH compared with conventional diffusion parameters.

[Distribution and drug resistance of pathogens of blood stream infection in patients with hematological malignancies after chemotherapy]

Objective: To investigate the distribution and resistance of pathogens isolated from blood cultures in patients with hematological malignancies after chemotherapy in Union Hospital of Fujian Medical University so as to understand the real situation of blood stream infection (BSI) and provide the basis for rational use of antibiotics in clinic. Methods: The data of 657 strains isolated from blood culture specimens of patients with hematological malignancies from January 2013 to December 2016 were collected analyzed. Results: A total of 657 cases of blood culture positive bacterial strains were included in the study, involving 410 cases (62.4%) with single Gram-negative bacteria (G(-) bacteria) , 163 cases (24.8%) with single Gram-positive bacteria (G(+) bacteria) , 50 cases (7.6%) with single fungi. The most common 5 isolates in blood culture were Klebsiella pneumoniae (17.5%) , Escherichia coli (17.2%) , Coagulase negative staphylococci (CNS) (14.9%) , Pseudomonas aeruginosa (14.2%) and Staphylococcus aureus (3.5%) . The extended-spectrum beta-lactamase (ESBL) production rates of Klebsiella pneumoniae and Escherichia coli were 25.2% and 55.8%, respectively. ESBL producing strains were almost more resistant than non-ESBL producing strains. The resistance rates of Enterobacteriaceae to carbapenems, piperacillin/tazobactam and tigecycline were lower than 14.0%. The resistance rates of Pseudomonas aeruginosa to a variety of drugs were lower than 12.0%. Tigecycline-resistant Acinetobacter baumannii bacteria were not detected, and the resistance rates of Acinetobacter baumannii to cefixime and cefotaxime were 7.1%. Methicillin-resistant strains in CNS (MRCNS) and in Staphylococcus aureus (MRSA) accounted for 84.7% and 43.5%, respectively. Vancomycin, linezolid and tigecycline-resistant G(+) bacteria were not detected. Conclusion: The pathogens isolated from blood culture were widely distributed. Most of them were G(-) bacteria, and the resistance to antibiotics was quite common. Furhermore, vancomycin, linezolid and tigecycline can be chosen empirically to treat patiens who ar suspected to have G(+) bacterial BSI.

Bone marrow-derived mesenchymal stem cells overexpressing MiR-21 efficiently repair myocardial damage in rats

Objective

We investigated the ability of bone marrow derived mesenchymal stem cells (BMSCs) overexpressing microRNA-21 (miR-21) to repair cardiac damage induced by anthracyclines in rats.

Methods

Sprague-Dawley (SD) rats of 2~3 weeks old were selected to isolate and culture BMSCs. A lentivirus harboring pLVX-miR-21 was generated and transfected into rat BMSCs. The rats were assigned into an untreated negative control group, and groups injected with adriamycin alone or with adriamycin followed by BMSCs, pLVX-BMSCs or pLVX-miR-21-BMSCs (n = 10 each). Proliferation and migration of cells were detected by cholecystokinin-8 (CCK- 8) and transwell. MiR-21 expression, mRNA expressions of B cell lymphoma 2 (Bcl2), BAX (BCL-2-associated X protein) and vascular endothelial growth factor (VEGF) were tested by qRT-PCR. Western blotting was applied to detect protein expressions of Bcl-2, Bax and VEGF.

Results

Using CCK- 8 and transwell assays, we found that pLVX-miR-21-BMSCs, which overexpressed miR-21, exhibited greater proliferation and migration than untransfected BMSCs or pLVX-BMSCs. Ultrasonic cardiograms and immunohistochemical analysis demonstrated that among the five groups, the pLVX-miR-21-BMSC group exhibited the most improved heart function and enhanced angiogenesis. Moreover, the pLVX-miR-21-BMSC group showed enhanced expression of Bcl-2, VEGF and Cx43 and reduced expression of Bax, BNP and troponin T.

Conclusion

These findings suggest miR-21 overexpression enhanced the proliferation, invasiveness and differentiation of BMSCs as well as expression of key factors (Bcl-2, VEGF and Bax) essential for repairing the cardiac damage induced by anthracyclines and restoring heart function.

In vitro effects of reprogramming factors on the expressions of pluripotent genes and CD34 gene in human acute promyelocytic leukemia HL-60 cells

OBJECTIVE

Our study aims to explore the in vitro effects of reprogramming factors on the expressions of pluripotent genes and CD₃₄ gene in HL-60 cells.

METHODS

According to the construction of lentiviral vector LV-OSCK of reprogramming factors (Oct-4, Sox2, Klf4, c-Myc), 293T cells were transfected to detect virus titer. The endogenous pluripotent genes (Oct4, SOX2, c-Myc and Klf4) and CD₃₄ mRNA and protein expressions were detected by AP staining, immunofluorescence staining, qRT-PCR and flow cytometry.

RESULTS

Expressions of Oct4, SOX2, c-Myc and Klf4 were 0.220±0.013, 0.186±0.009, 0.287±0.015 and 0.153±0.007. These levels were significantly higher in the experimental group than the control and blank groups. CD₃₄ protein expression in the experimental group was also discovered to be significantly higher than the other two groups.

CONCLUSION

The reprogramming factors could increase the expressions of pluripotent genes and CD₃₄ gene in HL-60 cells.

The Construction and Identification of Induced Pluripotent Stem Cells Derived from Acute Myelogenous Leukemia Cells

Objective: The present study aimed to establish an induced pluripotent stem cell (iPSC) line from acute myelogenous leukemia (AML) cells in vitro and identify their biological characteristics. Methods: Cells from the AML-infiltrated skin from an M6 patient were infected with a lentivirus carrying OCT4, SOX2, KLF4 and C-MYC to induce iPSCs. The characteristics of the iPSCs were confirmed by alkaline phosphatase (ALP) staining. The proliferation ability of iPSCs was detected with a CCK-8 assay. The expression of pluripotency markers was measured by immunostaining, and the expression of stem cell-related genes was detected by qRT-PCR; distortion during the induction process was detected by karyotype analysis; the differentiation potential of iPSCs was determined by embryoid body-formation and teratoma-formation assays. ALP staining confirmed that these cells exhibited positive staining and had the characteristics of iPSCs. Results: The CCK-8 assay showed that the iPSCs had the ability to proliferate. Immunostaining demonstrated that iPSC clones showed positive expression of NANOG, SSEA-3, SSEA-4, TRA-1-60 and TRA-1-81. qRT-PCR results revealed that the mRNA expression of Nanog, Lin28, Cripto, FOX3, DNMT3b, DPPA2, and DPPA4 significantly increased in iPSCs. Karyotype analysis found no chromosome aberration in the iPSCs. The results of the embryoid body-formation and teratoma-formation assays indicated that the iPSCs had the potential to differentiate into all three germ layers. Conclusion: Our study provided evidence that an iPSC line derived from AML cells was successfully established.

Effects of Blood Purification on Serum Levels of Inflammatory Cytokines and Cardiac Function in a Rat Model of Sepsis

OBJECTIVE

The study aimed to explore the effects of blood purification (BP) on serum levels of inflammatory cytokines and cardiac function in a rat model of sepsis.

METHODS

A rat model of sepsis was established by cecal ligation and puncture. All rats were divided into the normal control, sham operation, model, sham treatment, and BP treatment groups. Cardiac functions, inflammatory cytokines, myocardial enzymes, pathological score of cardiac muscle tissue, and myocardial apoptosis of rats in each group were compared.

RESULTS

Sepsis rats had higher serum levels of inflammatory cytokines and lower cardiac function than those in the normal control and sham operation groups. Compared with the model and sham treatment groups, improved cardiac functions, decreased inflammatory cytokines, myocardial enzymes, pathological score, and myocardial apoptosis and mortality were observed in the BP treatment group.

CONCLUSION

BP may reduce serum levels of inflammatory cytokines and improve cardiac function of sepsis rats.

Establishment of a nested-ASP-PCR method to determine the clarithromycin resistance of Helicobacter pylori

AIM: To investigate clarithromycin resistance positions 2142, 2143 and 2144 of the 23SrRNA gene in Helicobacter pylori (H. pylori) by nested-allele specific primer-polymerase chain reaction (nested-ASP-PCR).

METHODS: The gastric tissue and saliva samples from 99 patients with positive results of the rapid urease test (RUT) were collected. The nested-ASP-PCR method was carried out with the external primers and inner allele-specific primers corresponding to the reference strain and clinical strains. Thirty gastric tissue and saliva samples were tested to determine the sensitivity of nested-ASP-PCR and ASP-PCR methods. Then, clarithromycin resistance was detected for 99 clinical samples by using different methods, including nested-ASP-PCR, bacterial culture and disk diffusion.

RESULTS: The nested-ASP-PCR method was successfully established to test the resistance mutation points 2142, 2143 and 2144 of the 23SrRNA gene of H. pylori. Among 30 samples of gastric tissue and saliva, the H. pylori detection rate of nested-ASP-PCR was 90% and 83.33%, while the detection rate of ASP-PCR was just 63% and 56.67%. Especially in the saliva samples, nested-ASP-PCR showed much higher sensitivity in H. pylori detection and resistance mutation rates than ASP-PCR. In the 99 RUT-positive gastric tissue and saliva samples, the H. pylori-positive detection rate by nested-ASP-PCR was 87 (87.88%) and 67 (67.68%), in which there were 30 wild-type and 57 mutated strains in gastric tissue and 22 wild-type and 45 mutated strains in saliva. Genotype analysis showed that three-points mixed mutations were quite common, but different resistant strains were present in gastric mucosa and saliva. Compared to the high sensitivity shown by nested-ASP-PCR, the positive detection of bacterial culture with gastric tissue samples was 50 cases, in which only 26 drug-resistant strains were found through analyzing minimum inhibitory zone of clarithromycin.

CONCLUSION: The nested-ASP-PCR assay showed higher detection sensitivity than ASP-PCR and drug sensitivity testing, which could be performed to evaluate clarithromycin resistance of H. pylori.

Inhibition of Notch 1 receptor influenced the differentiation of Lin-CD45RA-dendritic cell precursors within ovarian carcinoma microenvironment

Background

Previous evidence suggested that the differentiation of Lin-CD45RA-DC precursors were prior to plasmcytoid dendritic cells (pDCs) than myeloid dendritic cells (mDCs) within ovarian cancer microenvironment. However, the mechanism is still unclear. Therefore, we investigated the function of Notch 1 signal pathway in the differentiation of Lin-CD45RA-DC precursors.

Methods

The CD34+ hematopoietic stem cells were extracted from umbilical cord blood in term parturition, and Lin-CD45RA-DC precusors were separated and induced mature. Expression of Notch1 receptor and ligands in Lin-CD45RA-DC precusors was detected by Real-time PCR and was down-regulated by shRNA or γ-secretase inhibitor (GSI). Flow cytometry was used to analyze the subset of DCs with or without SKOV3 culture supernatants. IL-12 level was detected by ELISA.

Results

Expression of Notch1 receptors and ligands were detected in Lin-CD45RA-DC precursor cells. The Notch1 mRNA in Lin-CD45RA-DC precursors can be down-regulated by shRNA-Notch1 lentivirus transfection and GSI. ShRNA mediated Notch 1 knock-down significantly differentiated less plasmcytoid dendritic cells (pDCs), but generated more myeloid dendritic cells (mDCs), and this would not be influenced by the supernatant of the ovarian carcinoma cell line. GSI had the same effect in the differentiation of pDC. The secretion of IL-12 significantly increased after Notch1 knock-down with or without SKOV3 culture supernatants.

Conclusions

Notch1 is an important signaling pathway in the differentiation of Lin-CD45RA-DC precursor cells to plasmcytoid dendritic cells (pDCs). And this would not be affected by the supernatant of the ovarian carcinoma cell line.

Prevalence and correlates of alcohol use and subsequent sexual activity among adult males in a rural community of ethnic minorities in Yunnan Province, China

This community-based cross-sectional study examined alcohol use and HIV risks among a sample of predominantly ethnic males in Yunnan Province, China. Information about alcohol use, sexual behavior, sex after drinking, and HIV infection was collected using face-to-face interviews and blood testing. Out of 497 potential male participants, 382 males agreed to participate in this study. Of these males, 70% were ethnic minorities, 74.1% were currently married, 95.5% were sexually experienced, 27.5% had used drugs, and 6% were HIV-infected. Over 81% were current drinkers and 55.7% started drinking before the age of 18. Among current drinkers, 44.5% drank daily and 31.9% had drunk heavily in the past 30 days. Baijiu (a Chinese liquor distilled from sorghum with an ethanol content of at least 40%) was the preferred drink of choice. Excessive alcohol use was associated with being an ethnic Jingpo (OR = 1.96), being a smoker (OR = 2.09) and having multiple lifetime sex partners (OR = 1.55). Over 21% reported having ever engaged in sex after drinking. Those who were aged 26 to 35 (OR = 3.80), started drinking before age 18 (OR = 2.14), who were heavy drinkers (OR = 1.99), or who had ever used drugs (OR = 2.00) were more likely to have ever engaged in sex after drinking. Health education programs for alcohol abuse and unwanted outcomes, particularly the risk of HIV, are urgently needed for ethnic males in Yunnan.

[Homing characteristics of graft cells in leukemia mice after allogenic bone marrow transplantation with different conditioning regimens]

The aim of this study was to investigate the homing characteristics of bone marrow cells in leukemia mice after allogenic bone marrow transplantation with different conditioning regimens on the basis of a leukemia mouse model. Allogenic bone marrow transplantation was performed after three different kinds of conditioning regimen, including nonmyeloablative conditioning regimen (5 Gy (60)Co γ ray total body irradiation, A group), radiotherapeutic myeloablative conditioning regimen (9 Gy (60)Co γ ray total body irradiation, B group) and chemotherapeutic myeloablative conditioning regimen (large dose chemotherapy, C group). In the recipient mice, the nucleated cell number in peripheral blood, bone marrow and spleen was counted, the percentage of positive cells capable of connecting with FITC labeled anti-mouse H-2K(b) antibody was detected by flow cytometry and the homing ratio in bone marrow and spleen was calculated at 24, 48, 72, 96 h after bone marrow transplantation. The results showed that donor myeloid cells displayed homing and then mobilization (going out of home) in group A; homing, mobilization, and rehoming in group B and C, and there was a little delay of homing in the spleen in group C. In bone marrow, the homing efficiency of A group was the highest in early period and the lowest [(0.90 ± 0.09)%] in the fourth day with the mobilization of myeloid cells (P < 0.05), and the homing efficiency of B and C groups was lower in the early period and the highest [(2.17 ± 0.26)%, B group] in the fourth day with the rehoming of myeloid cells (P < 0.05). In spleen, the homing efficiency was similar to that in bone marrow and there still was a little delay in C group. It is concluded that the homing ratio is high in the early period and decrease obviously in 72 h after bone marrow of leukemia mice treated with nonmyeloablative conditioning regimen. The homing ratio is low in the early period and increases obviously in 72 h after bone marrow of leukemia mice treated with radio-or chemotherapeutic myeloablative conditioning regimens. The homing ratio does not obviously change between the early period and 72 h after bone marrow of leukemia mice treated with chemotherapeutic myeloablative conditioning regimen, and lies between group A and B.

[Apoptosis-inducing effect of C-MYC siRNA on acute lymphoblastic leukemia Jurkat cell line]

The study was purposed to investigate the effects of C-MYC siRNA on the proliferation and apoptosis of acute lymphoblastic Jurkat cell line. siRNA targeting the site 1545-1565 of C-MYC mRNA was designed and chemically synthesized, then C-MYC siRNA was transfected into Jurkat cells by the transfer agent (HiPerFect Transfection Reagent), the morphological changes were observed under inverted microscope; the tetrazole compound (MTS) was applied to draw the cell growth curve; the cell colony test was used to detect the effect of C-MYC siRNA on the proliferation of Jurkat cells; the flow cytometry and TUNEL method were used to analyze the apoptosis of Jurkat cells. The results showed that after Jurkat cells were treated with different concentrations of C-MYC siRNA, the growth of Jurkat cells was inhibited to various degrees, inhibitory rate was enhanced as C-MYC siRNA concentration increased. C-MYC siRNA also could obviously inhibit the cell clony formation. The apoptosis of cells could be detected by flow cytometry and TUNEL method, the apoptosis rate of cells increased along with prolonging of treatment with C-MYC siRNA. It is concluded that the chemically synthesized C-MYC siRNA can inhibit significantly the proliferation and induce the apoptosis of Jurkat cells.

[Effects of small interference RNA against c-myc on expression of c-myc and h-tert genes in acute lymphoblastic leukemia cell line Jurkat]

This study was purposed to investigate the effect of small interfering RNA against c-myc on c-myc, h-tert gene and protein expressions in acute lymphoblastic leukemia cell line (Jurkat cells), so as to provide new methods and targets for gene therapy of leukemia. The siRNA against target sites 1545-1565 of c-myc mRNA was chemically synthesized and was transfected into Jurkat cells by transfectant. The c-myc, h-tert mRNA and protein expression levels before and after treatment with c-myc siRNA were detected by RT-PCR and Western blot, respectively. The results showed that c-myc siRNA obviously inhibited the proliferation of Jurkat cells, the half inhibitory concentration (IC50) for 48 hours was about 75 nmol/L. c-myc siRNA could decrease c-myc, h-tert mRNA and C-MYC, h-TERT protein expression levels of Jurkat cells. It is concluded that c-myc siRNA significantly reduce c-myc, h-tert mRNA and protein expression levels through inhibiting c-myc mRNA expression and decreasing intracellular level of C-MYC protein.

Induction with and without antithymocyte globulin combined with cyclosporine/tacrolimus-based immunosuppression in renal transplantation: a meta-analysis of randomized controlled trials

OBJECTIVE

The objective of this study was to conduct a meta-analysis of randomized controlled trials (RCT) to compare the effectiveness and safety of induction with and without antithymocyte globulin (ATG) combined with cyclosporine/tacrolimus-based immunosuppression in renal transplantation.

METHODS

Trials were identified through a computerized literature search of PubMed, EMBASE, Cochrane controlled trials register, Cochrane Renal Group Specialized Register of RCTs, and Chinese Biomedical database. Two independent reviewers assessed trials for eligibility and quality, and then extracted data. Data were extracted for patient and graft survival, acute rejection, the incidence of Banff, cytomegalovirus (CMV) infection, leukopenia, and thrombocytopenia. Dichotomous outcomes were reported as relative risk (RR) with 95% confidence intervals (CI).

RESULTS

Four RCTs (892 patients) were identified. The data showed that induction with ATG was more beneficial than no induction with ATG to reduce the incidence of chronic rejection (RR 0.70; 95% CI, 0.57-0.84) and acute rejection within 6 months (RR 0.68; 95% CI, 0.49-0.96) and at 12 months (RR 0.67; 95% CI, 0.50-0.89) as well as Banff II episodes (RR 0.53; 95% CI, 0.30-0.91), but increased the incidences of CMV infection (RR 1.61; 95% CI, 1.27-2.04) and leukopenia (RR 3.88; 95% CI, 2.80-5.38) and thrombocytopenia (RR 2.92; 95% CI, 1.77-4.04). There was no statistical difference between patient or graft survival rates at 6 and 12 months, as well as the incidences of Banff III or Banff I after transplantation.

CONCLUSION

Based on available data induction with ATG was more efficient to reduce the rate of acute rejection episodes and chronic rejection responses after renal transplantation, but was associated with increased side effects, particularly CMV infections. It is important to provide the most benefit for an individual patient.

Longitudinal analysis of circulating myeloma cells detected by allele specific mRNA in situ hybridization

Individual myeloma cells in the peripheral blood of 7 patients with multiple myeloma were detected by mRNA in situ hybridization (ISH) using biotinylated antisense oligonucleotide probes to non-germline sequences of the CDR3 region of the immunoglobulin heavy chain gene. Peripheral blood samples from these patients were studied over a period of 2-3 years. The number of circulating myeloma cells varied from 0.1-23% of the mononuclear cell population. Longitudinal studies showed that the highest number of circulating myeloma cells were present during escape phase and thus the percentage of mRNA ISH+ cells correlated with the clinical state of the patient. This technique is the most accurate means of monitoring and quantitating individual myeloma cells in the peripheral blood of patients with myeloma and provides insight into the relevance of circulating myeloma cells.

Genetic differentiation among three populations of Anopheles minimus of Guangxi and Yunnan Provinces in the People's Republic of China

Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, 'Yunnan-Field' (Y-F), was highly polymorphic at 14 of 20 loci (P = 0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively, Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).

Disease progression in patients with multiple myeloma is associated with a concurrent alteration in the expression of both oncogenes and tumour suppressor genes and can be monitored by the oncoprotein phenotype

The dysregulation of specific oncogenes due to either mutation or activation has previously been reported in a small number of patients with myeloma but the extent of oncogene dysregulation during the course of the disease is not known. The oncoprotein phenotype of plasma cells in 146 bone marrow samples from 81 patients with multiple myeloma was determined by dual colour flow cytometry using a predetermined panel of 8 monoclonal antibodies. High intensity CD38 expression was used to distinguish the plasma cell population and the cells were permeabilised to detect intracellular antigen expression. In situ hybridization using biotinylated cDNA probes for c-myc and bcl-2 was used to determine mRNA expression and to validate the flow cytometric assay. The normal range of expression for each of 6 oncoproteins (c-myc, c-fos, c-neu, bcl-2, p-ras, p53 mutant) and 2 tumour suppressor gene products (p53 wild and Rb) was determined in plasma cells from 33 normal bone marrows. Disease progression was associated with the concurrent abnormal expression of at least one oncogene and one tumour suppressor gene where as stable disease was associated with a normal expression of at least one or both (chi2 = 34.1; p < 0.001). At diagnosis there was a correlation between serum beta2 microglobulin and the concurrent overexpression of both an oncoprotein and a tumour suppressor gene product. Longitudinal studies of 33 different patients over 4 years, suggests that the progressive evolution of myeloma is a multistep process of genomic instability producing ongoing alterations in the expression of both oncogenes and tumour suppressor genes.

Genetic differentiation among three populations of Anopheles minimus of Guangxi and Yunnan Provinces in the People's Republic of China

Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, Y-F, was highly polymorphic at 14 of 20 loci (P=0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively. Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).

Nucleoside transporters, bcl-2 and apoptosis in CLL cells exposed to nucleoside analogues in vitro

The purine nucleoside analogues fludarabine (F1) and chlorodeoxyadenosine (2-CdA) are considered to be cell cycle specific agents which require DNA synthesis for cytotoxicity. However, their efficacy in the treatment of CLL, an indolent lymphoid malignancy suggests additional mechanisms of action. Like cytosine arabinoside (AraC), F1 and 2-CdA gain access to the cell via a specific nucleoside transporter (NST) protein. To investigate the mode of action of these drugs in CLL, we used a fluorescent ligand for the NST (5'-(SAENTA- x8)-fluorescein) and 3-colour flow cytometry to determine NST expression on CD5+/CD19+ B-cells from the peripheral blood (PB) of patients with CLL. NST levels on these cells was found to be not significantly different from normal control lymphocytes (mean = 485 +/- 425) vs. (mean = 553 +/- 178). Exposure to varying concentrations (0, 3 microM and 30 microM) of F1 and 2-CdA, however, resulted in an upregulation of NST (mean = 1552 +/- 775 with 30 microM FL; mean = 3392 +/- 2197 with 30 microM 2-CdA) after 48. "Large" lymphoid cells (not present in normal PB) were found to express significantly more NST (mean = 2540 +/- 2861) and have a higher proliferative capacity than "small" cells (mean = 357 +/- 517 NST/cell). Incubation of CLL cells with F1 (n = 6) and 2-CdA (n = 8) in vitro over 48 h also resulted in an increase in the proportion of cells in S-phase (0 microM = 0.2 + 2 - 0.1; 30 microM FL = 2.4 +/- 2.0; 30 microM 2-CdA = 3.3 +/- 1.3) and a significant increase in morphologically identifiable apoptosis. Apoptosis was confirmed by flow cytometric DNA analysis (0 microM = 13 +/- 8%; 30 microM FL = 40 +/- 20%; 30 microM 2-CdA = 48 +/- 11%). In situ hybridization using a biotinylated cDNA bcl-2 probe demonstrated that bcl-2 mRNA expression was markedly decreased in treated cells after 24 h. These studies have demonstrated that: (1) NST expression on CLL lymphocytes is low; (2) in vitro exposure to the analogues increases both the level of NST expression and the % cells in S-phase; (3) exposure to the analogues downregulates bcl-2 expression and increases apoptosis.

Idiotypic oligonucleotide probes to detect myeloma cells by mRNA in situ hybridization

An mRNA in situ hybridization (ISH) method which used non-radioactive idiotypic oligonucleotide probes has been used to detect malignant cells in the bone marrow and peripheral blood of patients with multiple myeloma. For each of two patients with multiple myeloma a pair of biotinylated antisense oligonucleotide probes (18-22mer) was prepared from non-germline sequences of the rear-ranged immunoglobulin heavy chain (IgH) gene. These oligonucleotide sequences were not homologous with any previously published sequence. The probes from each patient were specific as shown by a failure to hybridize to any cells from six other myeloma patients and four normal individuals. Specific staining of IgH gene mRNA occurred only when the myeloma cells and the sequence of the probe used were from the same patient. Using simultaneous fluorescent immunocytochemistry it was shown that more than 95% of the ISH-positive cells expressed the malignant light chain in their cytoplasm. ISH positive cells were found in 1-4% of the peripheral blood mononuclear fraction of these two patients. These studies show that idiotypic oligonucleotide IgH gene probes can be used to identify individual cells belonging to the malignant clone and offer the possibility of developing innovative tumour-specific therapeutic procedures using antisense technology for patients with myeloma.

The oncoprotein phenotype of plasma cells from patients with multiple myeloma

The expression of 6 different oncoproteins and 2 tumour suppressor gene products in the plasma cells of 63 bone marrow samples was used to determine a profile of the oncogenic phenotype of patients with multiple myeloma. Dual label flow cytometry after periodatelysine paraformaldehyde fixation was used to detect cell surface phenotype and intracellular protein expression simultaneously. The normal range for both the incidence and intensity of expression was determined for each protein by analysing plasma cells (high CD38 intensity) in 22 normal bone marrow samples. The percentage of myeloma patients with a greater than normal incidence of plasma cells expressing these proteins was 53% for c-myc, 28% for Rb, 28% for bcl-2, 27% for c-fos, 24% for p53 wild, 22% for p53 mutant, 13% for c-neu and 13% for pan-ras. When a panel of 8 antibodies was used, 82% of the samples (n = 28) had an increased incidence of expression by at least one oncoprotein or tumour suppressor gene product. The 5 patients with a normal incidence of expression of all 8 proteins were in plateau stage and 4 had not received chemotherapy for more than 12 months. The number of patients with an increased incidence of expression by 2 or more oncoproteins was significantly greater (X2 = 9.0; p < 0.005) in progressive disease (55%) than in stable disease (14%) but there was no specific phenotype pattern associated with progressive disease. All 6 oncoproteins and both tumour suppressor gene products had a greater incidence and intensity of expression in progressive than in stable disease. The expression of c-myc oncoprotein correlated with c-myc mRNA expression in the same samples (n = 10) but c-myc did not correlate with either the plasma cell labelling index (r = -0.15) nor serum thymidine kinase (r = 0.10). Our results suggest that there is a heterogeneous, non-systematic but almost universal presence of activated oncogenes and tumour suppressor genes in the plasma cells of patients with multiple myeloma and that disease progression is associated with the accumulation of a variety of secondary genetic changes which confer increased malignant behaviour.