Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector

This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13  TeV and corresponding to an integrated luminosity of 137  fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst)  pb.

Measurement of the Centrality Dependence of the Dijet Yield in p+Pb Collisions at sqrt[s_{NN}]=8.16 TeV with the ATLAS Detector

ATLAS measured the centrality dependence of the dijet yield using 165  nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16  TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.

Search for New Phenomena in Two-Body Invariant Mass Distributions Using Unsupervised Machine Learning for Anomaly Detection at sqrt[s]=13 TeV with the ATLAS Detector

Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140  fb^{-1} of pp collisions at sqrt[s]=13  TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,μ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.

Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst)  fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06  fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.

Combined Measurement of the Higgs Boson Mass from the H→γγ and H→ZZ^{*}→4ℓ Decay Channels with the ATLAS Detector Using sqrt[s]=7, 8, and 13 TeV pp Collision Data

A measurement of the mass of the Higgs boson combining the H→ZZ^{*}→4ℓ and H→γγ decay channels is presented. The result is based on 140  fb^{-1} of proton-proton collision data collected by the ATLAS detector during LHC run 2 at a center-of-mass energy of 13 TeV combined with the run 1 ATLAS mass measurement, performed at center-of-mass energies of 7 and 8 TeV, yielding a Higgs boson mass of 125.11±0.09(stat)±0.06(syst)=125.11±0.11  GeV. This corresponds to a 0.09% precision achieved on this fundamental parameter of the Standard Model of particle physics.

Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector

A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139  fb^{-1} of sqrt[s]=13  TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.

Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector

This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02  TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72  nb^{-1} and 257  pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158 Collapse

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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings

A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13  TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8  pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.

Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector

A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.

[The prognostic value of free triiodothyronine/free thyroxine ratio in patients hospitalized with heart failure]

Objective: To investigate the effect of free triiodothyronine/free thyroxine (FT3/FT4) ratio on the prognosis of patients with heart failure (HF). Methods: A total of 3 527 patients hospitalized in the Heart Failure Center of Fuwai Hospital from March 2009 to June 2018 were analyzed in our study. Patients were divided into two groups according to median of FT3/FT4 ratio: low FT3/FT4 group (n=1 764, FT3/FT4<2.15) and high FT3/FT4 group (n=1 763, FT3/FT4≥2.15). The primary endpoint was defined as a composite endpoint of all-cause death or heart transplantation or implantation of a left ventricular assist device. The baseline characteristics of patients with different FT3/FT4 ratio groups were compared, and a multivariate Cox proportional hazard regression model was used to analyze the relationship between FT3/FT4 ratio and the prognosis of hospitalized patients with HF. Results: The age of the total population was (56.8±16.0) years, and 2 544 cases (72.1%) were males. The median follow-up time was 2.79 (1.00, 5.03) years, and a total of 1 542 end-point events were recorded at the final follow-up. The mean ages of patients in the low FT3/FT4 group and high FT3/FT4 group were (58.8±16.5) and (54.8±15.2) years (P<0.001), respectively; and the cumulative survival rates were 38.4% and 61.9%, respectively (P<0.001). FT3 (HR=0.72, 95%CI: 0.63-0.84, P<0.001), FT3/FT4 (HR=0.76, 95%CI: 0.65-0.87, P<0.001) was associated with all-cause death, heart transplantation, or LVAD implantation in patients with heart failure. HR values (95%CI) of FT3/FT4 ratio predicting the risk of composite endpoint in the subgroup of left ventricular ejection fraction (LVEF)<40%, 40% to 49%, and≥50% were 0.91 (0.77-1.08), 0.83 (0.50-1.39), and 0.65 (0.50-0.85), respectively (P interaction=0.045). Conclusions: Low FT3 and low FT3/FT4 are important correlative factors for poor prognosis in hospitalized HF patients, especially in patients with LVEF≥50%.

[Clinical features and prognosis of patients hospitalized with heart failure and low T3 syndrome]

Objective: To investigate the association between triiodothyronine (T₃) and inflammatory factors, and its potential effect on long-term outcomes in hospitalized patients with heart failure (HF). Methods: A total of 2 475 patients with HF admitted in Heart Failure Care Unit were consecutively enrolled in this retrospective cohort study from December 2006 to June 2018. Patients were divided into low T₃ syndrome group (n=610, 24.6%) and normal thyroid function group (n=1 865, 75.4%). The median follow-up time was 2.9 (1.0, 5.0) years. A total of 1 048 all-cause deaths were recorded at the final follow-up. The effects of free T₃ (FT₃) and high-sensitivity C-reactive protein (hsCRP) on the risk of all-cause death were evaluated by Cox regression analysis and Kaplan-Meier analysis. Results: The age of the total population was 19-95 (57±16) years, 1 823 cases (73.7%) were male. Compared to those with normal thyroid function, albumin [(36.5±5.4) vs. (40.7±4.7) g/L], hemoglobin [(129.4±25.1) vs. (140.6±20.6) g/L], total cholesterol [3.6 (3.0, 4.4) vs. 4.2 (3.5, 4.9) mmol/L] (all P<0.001) were lower, Whereas age [(60.5±16.0) vs. (55.2±15.4) years], creatinine [105.0 (83.6, 137.0) vs. 87.8 (75.6, 106.3) mmol/L], log N-terminal B-type natriuretic peptide [(8.2±1.3) vs. (7.2±1.4) ng/L] were higher in LT₃S patients (all P<0.001). In Kaplan-Meier survival analysis, patients with lower FT₃ and higher hsCRP had significantly lower cumulative survival (P<0.001), lower FT₃ combined with higher hsCRP subgroup had the highest risk of all-cause death (P_trend<0.001). In multivariate Cox regression analysis, LT₃S was an independent predictor of all-cause mortality (HR=1.40, 95%CI 1.16-1.69, P<0.001). Conclusion: LT₃S is an independent predictor of poor prognosis in patients with heart failure. FT₃ combined with hsCRP improve the predictive value of all-cause death in hospitalized patients with heart failure.

[Clinical characteristics of hypertrophic cardiomyopathy and restricted cardiomyopathy patients complicating with intracardiac thrombosis]

Objective: To investigate the clinical characteristics of patients with hypertrophic cardiomyopathy (HCM) and restrictive cardiomyopathy (RCM) complicating with intracardiac thrombosis. Methods: This is a retrospective observational study. Consecutive patients diagnosed with HCM or RCM and complicated with intracardiac thrombosis (including left and right atrium or ventricular thrombosis), who were admitted to the Heart Failure Care Unit of Fuwai Hospital, Chinese Academy of Medical Sciences, from September 2008 to September 2018, were enrolled in this study. Patients with myocardial infarction were excluded. The general clinical data of the enrolled patients, including demographic data, major complications, laboratory indicators, echocardiographic indicators, drug application and distribution of intracardiac thrombosis, were collected from electronic medical record system and analyzed. Results: A total of 98 patients were enrolled in this study, including 52 patients (53.1%) with HCM and 46 patients (46.9%) with RCM. The most common comorbidity was atrial fibrillation/flutter: 40 patients (76.9%) in HCM group and 36 patients (78.3%) in RCM group. Majority of patients received oral anticoagulants treatment: 43 patients (82.7%) in HCM group and 35 patients (76.1%) in RCM group. Intracardiac thrombosis was mainly located in the left atrium in both HCM group (39 cases (75.0%)) and RCM group (32 cases (69.6%)). Thrombosis was found in ≥ 2 chambers in 7 patients (7.1%). Rate of left atrial thrombosis was the highest (81.6% (62/76)) in HCM and RCM patients complicating with atrial fibrillation/flutter. Intra-aneurysmal thrombosis occurred in 4 out of 5 patients complicated with apical left ventricular aneurysm. The rate of left ventricular thrombosis in patients with left ventricular ejection fraction≥50% was 7.4% (4/54), which was significantly lower than that in patients with left ventricular ejection fraction<50% (34.5%(10/29)) (P<0.01). Conclusion: There are certain distribution characteristics of HCM and RCM patients with intracardiac thrombosis, and the left atrium is the most common site of thrombosis, more attention should be paid in HCM and RCM patients on the diagnosis and treatment of intracardiac thrombosis.

[The Ophthalmology-centered medical industry in Suzhou in the Ming and the Qing Dynasties - from the Painting Album of Cityscapes and Business]

The Painting Album of Cityscapes and Business was finished in the early Qing Dynasty with realism. This painting album described the prosperity in business and everyday life in Suzhou during the late Ming and the early Qing Dynasties. They were drawn and painted retrospectively, ie, the content of the pictures was based on existing paintings handed down. In the painting album, more than ten medical-related elements were specifically depicted, such as traditional Chinese medicine clinics and pharmacies and seven ophthalmology-related elements including one clinic specialized in ophthalmology, two spectacle shops, two people wearing eyeglasses and three blind people. Up to now, no specialized ophthalmology clinics and spectacle shops have been found in earlier literature and paintings. It can be speculated that the Painting Album of Cityscapes and Business is the earliest album of paintings depicting clinics specialized in ophthalmology and spectacle shops in China. This painting album provides important information for the study of the medical industry in Suzhou in the late Ming and the early Qing Dynasties, particularly, in terms of ophthalmology-related diagnosis and treatment.

A novel therapy, using Ghrelin with pegylated G-CSF, inhibits brain hemorrhage from ionizing radiation or combined radiation injury

Medical treatment becomes challenging when complicated injuries arise from secondary reactive metabolic and inflammatory products induced by initial acute ionizing radiation injury (RI) or when combined with subsequent trauma insult(s) (CI). With such detrimental effects on many organs, CI exacerbates the severity of primary injuries and decreases survival. Previously, in a novel study, we reported that ghrelin therapy significantly improved survival after CI. This study aimed to investigate whether brain hemorrhage induced by RI and CI could be inhibited by ghrelin therapy with pegylated G-CSF (i.e., Neulasta®, an FDA-approved drug). B6D2F1 female mice were exposed to 9.5 Gy 60Co-γ-radiation followed by 15% total-skin surface wound. Several endpoints were measured at several days. Brain hemorrhage and platelet depletion were observed in RI and CI mice. Brain hemorrhage severity was significantly higher in CI mice than in RI mice. Ghrelin therapy with pegylated G-CSF reduced the severity in brains of both RI and CI mice. RI and CI did not alter PARP and NF-κB but did significantly reduce PGC-1α and ghrelin receptors; the therapy, however, was able to partially recover ghrelin receptors. RI and CI significantly increased IL-6, KC, Eotaxin, G-CSF, MIP-2, MCP-1, MIP-1α, but significantly decreased IL-2, IL-9, IL-10, MIG, IFN-γ, and PDGF-bb; the therapy inhibited these changes. RI and CI significantly reduced platelet numbers, cellular ATP levels, NRF1/2, and AKT phosphorylation. The therapy significantly mitigated these CI-induced changes and reduced p53-mdm2 mediated caspase-3 activation. Our data are the first to support the view that Ghrelin therapy with pegylated G-CSF is potentially a novel therapy for treating brain hemorrhage after RI and CI.

Multiple functions of miR-8-3p in the development and metamorphosis of the red flour beetle, Tribolium castaneum

The microRNA miR-8-3p is conserved among insects and closely involved in development and immunity, but its functions in vivo are unexplored in the red flour beetle, Tribolium castaneum. Here, we show that miR-8-3p was highly expressed in late larva and early adult stages, as determined by quantitative real-time PCR. It was enriched in the fat body and cuticle in late larval tissues and abundant in the head and cuticle in early adult tissues, indicating this microRNA plays important roles during T. castaneum development. Specific inhibition of miR-8-3p in late larvae led to metamorphosis defects in the development of wings, eyes, legs and embryo. Moreover, a series of genes related to organism development were identified as miR-8-3p targets by computational prediction and microRNA-messenger RNA interaction validation, including Wingless, Eyg, Fpps and Sema-1a. These genes were critical for the regulation of the larva-to-adult transition. Eyg, as a functional target of miR-8-3p, participates in eye development, which was further confirmed by luciferase assay and loss-of-function analyses. In brief, miR-8-3p is broadly involved in the development of wings, eyes and legs through its target genes and has extensive regulatory roles during T. castaneum development.

Both JrWRKY2 and JrWRKY7 of Juglans regia mediate responses to abiotic stresses and abscisic acid through formation of homodimers and interaction

WRKY transcription factors belong to a large protein family that is involved in diverse developmental processes and abiotic stress responses. Currently, there is little understanding of the role of WRKY transcription factors in regulatory mechanisms in plants, especially in the protein-protein interactions that are essential for biological regulatory functions and networks. In the present study, yeast one-hybrid, yeast two-hybrid, transient expression and quantitative RT-PCR were applied to investigate the potential characteristics of two WRKY proteins from Juglans regia, JrWRKY2 (GenBank Accession No. KU057089) and JrWRKY7 (GenBank Accession No. KP784651). JrWRKY2 and JrWRKY7 can form homodimers and interact with each other. JrWRKY2 and JrWRKY7 can bind to W-box motifs. Similarly high levels of transcription were found for JrWRKY2 and JrWRKY7 under NaCl and polyethylene glycol (PEG) stresses, as well as at different developmental stages, e.g., the pistil or terminal leaf. JrWRKY2 and JrWRKY7 were transiently overexpressed in an independent manner in the terminal leaf. Analyses of superoxide dismutase (SOD) and peroxidase (POD) activities, proline and malondialdehyde (MDA) contents, and electrolyte leakage rate showed that JrWRKY2 and JrWRKY7 overexpression improved plant tolerance to NaCl, PEG, abscisic acid, and cold stress. Additionally, JrWRKY2 and JrWRKY7 overexpression elevated transcription of SOD, POD, glutathione peroxidase (GPX), catalase (CAT), ascorbate peroxidase (APX), and MYB genes, but downregulated the expression of NAC. Overall, the results demonstrate that JrWRKY2 and JrWRKY7 are dimeric proteins that can form functional homodimers and interact with each other and that they are involved in abiotic stress responses.

Controllable Synthesis of a Smart Multifunctional Nanoscale Metal-Organic Framework for Magnetic Resonance/Optical Imaging and Targeted Drug Delivery

As a result of their extraordinarily large surfaces and well-defined pores, the design of a multifunctional metal-organic framework (MOF) is crucial for drug delivery but has rarely been reported. In this paper, a novel drug delivery system (DDS) based on nanoscale MOF was developed for use in cancer diagnosis and therapy. This MOF-based tumor targeting DDS was fabricated by a simple postsynthetic surface modification process. First, magnetic mesoporous nanomaterial Fe-MIL-53-NH₂ was used for encapsulating the drug and served as a magnetic resonance contrast agent. Moreover, the Fe-MIL-53-NH₂ nanomaterial exhibited a high loading capacity for the model anticancer drug 5-fluorouracil (5-FU). Subsequently, the fluorescence imaging agent 5-carboxyfluorescein (5-FAM) and the targeting reagent folic acid (FA) were conjugated to the 5-FU-loaded Fe-MIL-53-NH₂, resulting in the advanced DDS Fe-MIL-53-NH₂-FA-5-FAM/5-FU. Owing to the multifunctional surface modification, the obtained DDS Fe-MIL-53-NH₂-FA-5-FAM/5-FU shows good biocompatibility, tumor enhanced cellular uptake, strong cancer cell growth inhibitory effect, excellent fluorescence imaging, and outstanding magnetic resonance imaging capability. Taken together, this study integrates diagnostic and treatment aspects into a single platform by a simple and efficient strategy, aiming for facilitating new possibilities for MOF use for multifunctional drug delivery.

The influence of cytidine deaminase -33delC polymorphism on treatment outcome with high-dose cytarabine in Chinese patients with relapsed acute myeloid leukaemia

WHAT IS KNOWN AND OBJECTIVE

Identification of biomarkers that could predict high-dose cytarabine (Ara-C) efficacy and toxicity is a key issue in individualized therapy. The aim of our study was to evaluate the influence of cytidine deaminase (CDA) single nucleotide polymorphisms (SNPs) -451G>A (rs532545), 435C>T (rs1048977) and -33delC (rs3215400) on treatment outcome in patients with relapsed acute myeloid leukaemia (AML) after high-dose Ara-C chemotherapy.

METHODS

In total, 173 patients with relapsed AML, treated with high-dose Ara-C chemotherapy, were genotyped for three polymorphisms in CDA gene using the allele-specific matrix-assisted laser desorption/ionization time-of-flight mass spectrometry assays. Binary logistic regression was used to evaluate the influence of selected polymorphisms on tumour response and occurrence of treatment-related toxicity.

RESULTS AND DISCUSSION

The CC genotype at -33delC, a promoter polymorphism, increased the odds of overall response rate (odds ratio [OR] = 5·125; 95% confidence intervals (CI) = 2·446-10·74; P = 0·0008) and grade ≥3 infection toxicity incidence rate (OR = 3·572; 95% CI = 1·68-7·594; P = 0·003). In multivariable analysis, this polymorphism was a potential independent prognostic marker for the risk of overall response (P = 0·011), but not grade ≥3 infection toxicity incidence rate (P = 0·49). Two other polymorphisms, -451G>A and 435C>T, did not influence treatment outcome, including overall response rate, infection toxicity and nausea/vomiting, in patients with relapsed AML (P > 0·05).

WHAT IS NEW AND CONCLUSION

The findings suggest that CDA -33delC variant might be a potential marker for predicting treatment outcome in Chinese patients with relapsed AML given high-dose cytarabine chemotherapy.

Algorithms for Two Gate Optimization in Injection Molding

In injection molding, the injection pressure is often limited by the capacity of injection machines. Therefore, for large-volume part, multiple gates are needed so that the maximum flow path can be shortened, with a corresponding decrease in injection pressure. Many components produced by injection molding today require more than one gate. As multiple gates affect resin flow in a mold interactively, their locations might not be easily determined. For a mold with two gates, a pressure gradient search scheme (PGSS) is proposed to optimize their locations in this investigation. A search direction associated with pressure gradient is developed based on the physical nature of the mold-filling process. An alternative scheme based on genetic algorithm is also employed for comparison. Through minimizing the objective function of injection pressure, the optimum gates can be located to achieve balanced flow. Examples indicate that the proposed pressure gradient search scheme is more efficient than genetic algorithm for two gate location optimization.

Carvedilol reduces myocardial no-reflow by decreasing endothelin-1 via activation of the ATP-sensitive K+ channel

It has been verified that carvedilol can attenuate myocardial no-reflow. However, the effects of carvedilol on adenosine triphosphate-sensitive K+ (KATP) channel and endothelin-1 (ET-1) are unknown. Forty mini-swines were randomized into 5 study groups: 8 control, 8 carvedilol pretreatment, 8 glibenclamide (KATP channel blocker)-treated, 8 carvedilol and glibenclamide-pre-treated and 8 sham-operated. An acute myocardial infarction(AMI) and reperfusion model was created with a three-hour occlusion of the left anterior descending coronary artery followed by one-hour reperfusion. Compared with the control group, carvedilol significantly decreased the area of no-reflow (myocardial contrast echocardiography: from 78.5±4.5% to 24.9±4.1%, pathological means: from 82.3±1.9% to 25.8±4.3% of ligation area, respectively; all p < 0.01) and reduced necrosis size from 98.5±1.3% to 74.4±4.7% of ligation area, p < 0.05). It also decreased plasma ET-1 and myocardial tissue ET-1. However, glibenclamide abrogated the protective effect of carvedilol. The beneficial effect of carvedilol on myocardial no-reflow could be due to its effect on ET-1 via the activation of the KATP channel.

Accumulation of Mn(II) in Deinococcus radiodurans facilitates gamma-radiation resistance

Deinococcus radiodurans is extremely resistant to ionizing radiation. How this bacterium can grow under chronic gamma radiation [50 grays (Gy) per hour] or recover from acute doses greater than 10 kGy is unknown. We show that D. radiodurans accumulates very high intracellular manganese and low iron levels compared with radiation-sensitive bacteria and that resistance exhibits a concentration-dependent response to manganous chloride [Mn(II)]. Among the most radiation-resistant bacterial groups reported, Deinococcus, Enterococcus, Lactobacillus, and cyanobacteria accumulate Mn(II). In contrast, Shewanella oneidensis and Pseudomonas putida have high iron but low intracellular manganese concentrations and are very sensitive. We propose that Mn(II) accumulation facilitates recovery from radiation injury.

[In vitro autonomous growth of megakaryocytic progenitors and the role of thrombopoietin (Tpo) in essential thrombocythemia]

OBJECTIVE

To investigate in vitro autonomous growth of megakaryocytic progenitors and the role of Tpo in essential thrombocythemia (ET).

METHODS

Purified bone marrow and peripheral blood CD(34)(+) cells and nonadherent mononuclear cells (NMNC) from patients with ET were cultured to assay the spontaneous megakaryocyte colony formation. The autocrine and paracrine of Tpo in the spontaneous growth cells in liquid culture were examined by RT-PCR. The effect of Tpo on megakaryocytic progenitors was observed by addition of Tpo into CD(34)(+) cell culture.

RESULTS

There was no spontaneous CFU-MK growth in purified CD(34)(+) cell culture and spontaneous megakaryocyte colonies disappeared at NMNC cell concentrations of 10(4)/ml and 10(3)/ml. There was no Tpo expression in the spontaneous growth cells in liquid culture. Addition of Tpo to the culture of purified CD(34)(+) cells resulted in the formation of megakaryocyte colonies.

CONCLUSION

In vitro spontaneous CFU-MK formation in ET patients is not from autonomous growth of megakaryocyte progenitors. There is no autocrine or paracrine Tpo secretion. Megakaryocyte progenitors may be hypersensitive to Tpo or other MK-CSF.

[Proliferative signal transmission mediated by EpoR in leukemic cell lines]

OBJECTIVE

To investigate the expression of erythropoietin receptor (EpoR) in leukemic cell lines and to clarify the mechanism of proliferative signal transmission in the leukemic cell line KOCL-33 mediated by EpoR.

METHODS

Biotinylated Epo and flow cytometry were used for EpoR expression, (3)H-TdR incorporation for cell proliferation, immunoprecipitation and Western blot analysis for the tyrosine phosphorylation of signal transmission proteins.

RESULTS

(1) All the cell lines tested expressed EpoR except for T-lymphoid cell lines. The positivity rates ranged from 18% to 99% with an average of 52%, and was no difference among T, B and non-lymphoid cells. (2) The cell proliferation was significantly enhanced in response to Epo in 7 of 9 cell lines tested. The stimulating effects of Epo did not correlate with the densities of EpoR expressed on the cells. (3) The proliferation of KOCL-33 cells was significantly enhanced in response to Epo. Dimerization and tyrosine phosphorylation of EpoR and tyrosine phosphorylation of JAK2 occurred in 1 min and tyrosine phosphorylation of STAT5 in 5 minutes after Epo stimulation.

CONCLUSION

(1) There was EpoR expression in leukemic cell lines. (2) The cell proliferation could be stimulated by Epo in some leukemic cell lines. The stimulating effect of Epo did not correlate with the densities of EpoR expressed on the cells. (3) Dimerization and tyrosine phosphorylation of EpoR occurred, and JAK2, STAT5 involved in the proliferative signal transmission in KOCL-33 cells mediated by EpoR.

Engineering Deinococcus radiodurans for metal remediation in radioactive mixed waste environments

We have developed a radiation resistant bacterium for the treatment of mixed radioactive wastes containing ionic mercury. The high cost of remediating radioactive waste sites from nuclear weapons production has stimulated the development of bioremediation strategies using Deinococcus radiodurans, the most radiation resistant organism known. As a frequent constituent of these sites is the highly toxic ionic mercury (Hg) (II), we have generated several D. radiodurans strains expressing the cloned Hg (II) resistance gene (merA) from Escherichia coli strain BL308. We designed four different expression vectors for this purpose, and compared the relative advantages of each. The strains were shown to grow in the presence of both radiation and ionic mercury at concentrations well above those found in radioactive waste sites, and to effectively reduce Hg (II) to the less toxic volatile elemental mercury. We also demonstrated that different gene clusters could be used to engineer D. radiodurans for treatment of mixed radioactive wastes by developing a strain to detoxify both mercury and toluene. These expression systems could provide models to guide future D. radiodurans engineering efforts aimed at integrating several remediation functions into a single host.

[Secretive activity of tumor necrosis factor alpha (TNF alpha) of marrow stromal cells in acute leukemia and its clinical significance]

OBJECTIVE

To investigate the TNF alpha secreting activity of marrow stromal cells in acute leukemia.

METHODS

TNF alpha in vitro culture supernate of marrow stromal cells from 20 acute leukemia patients and 10 normal controls was detected. TNF alpha activities in patients and control serum and in patients leukemic cell culture supernate were also detected.

RESULTS

TNF alpha activity in leukemic stromal cell supernate was significantly higher than that of the control (P < 0.05). Some AML cell could spontaneously secret TNF alpha. Serum TNF alpha activity of the patient group is also evidently higher than that of the control group (P < 0.001).

CONCLUSION

There were qualitative and quantitative defects of marrow stromal cells in acute leukemia patients. Increased secretion of TNF alpha is probably an important factor leading to the abnormal proliferation of acute leukemia cells.

[Determination of formaldehyde in indoor air by gas chromatography]

Formaldehyde in indoor air was collected by water, derivatized with 2,4-dinitrophenylhydrazine and extracted by cyclohexane. The sample was separated on an OV-17 and QF-1 mixed chromatographic column and determined by electron capture detector. The detection limit was 0.02 mg/L (solution), the minimum detectable concentration was 0.01 mg/m3 while 10 L indoor air was collected. The results show that this is a rapid and sensitive method with less interferences and fairly good precision. The recoveries were 71.0%-90.4% and coefficients of variation were 4.1%-6.5%. The development of this method has made a reliable methodological foundation for the determination of formaldehyde in indoor air.

[Allogeneic bone marrow transplantation for a patient with malignant histiocytosis]

OBJECTIVE

To observe the efficacy and side effects of allogeneic bone marrow transplantation (allo-BMT) in the treatment of malignant histiocytosis (MH).

METHODS

After conditioning with chemotherapy and total body irradiation, HLA-A, B, DR, DQ compatible allo-BMT was performed in a patient with MH.

RESULTS

DNA fingerprinting showed engraftment on day 22, bone marrow aspiration showed hypercellularity on day 50, and no abnormal cell was found. The patient developed acute graft-versus-host disease ( II degrees) on day 40 and herpes zoster 6 months post-transplantation, and the patient has survived disease-freely for 24 months after allo-BMT.

CONCLUSION

This is the first report of treatment of MH with allo-BMT in China, showing that allo-BMT may significantly prolong the survival of MH.

[Changes of peripheral blood stem cells of patients with malignant hematopoietic tumor after chemotherapy]

To investigate the most appropriate condition for collecting stem cells during peripheral blood stem cells transplantation (PBSCT), we used colony forming unit-granulocyte, macrophage (CFU-GM) as index to observe the change of PBSC after chemotherapy in 12 patients with malignant hematopoietic tumor. The results showed that it was more suitable to collect PBSC when the number of leucocytes was 2 x 10(9)/L, neutrophils 0.8 x 10(9)/L and platelets 110 x 10(9)/L after chemotherapy for 2 weeks. After chemotherapy, the number of leucocytes were suppressed evidently. On the contrary, a lot of CFU-GM appeared during the recovery phase of peripheral hemogram. At the nadir of peripheral hemogram, the number of leucocytes correlated negatively with the number of CFU-GM (P < 0.05). The longer the time of chemotherapy, the less the CFU-GM that in the same patients. After chemotherapy the CD34+ cells which appeared early might not form CFU-GM, but the CD34+ cells at the recovery phase of peripheral hemogram had the same trend of change with CFU-GM.

[Bone marrow necrosis and malignant tumors]

Twelve patients with bone marrow necrosis were diagnosed in our hospital during the past thirteen years. All were related to malignant tumors. Bone marrow metastatic carcinoma was diagnosed in 5, suspicious metastatic carcinoma in 3, acute leukemia in 2, chronic granulocytic leukemia in 1 and malignant histiocytosis in 1. In case 1, the necrosis was secondary to gastric cancer metastasis into the bone marrow and complicated by microangiopathic hemolytic anemia; in case 3, bone marrow necrosis was the initial manifestation and a diagnosis of acute lymphocytic leukemia was finally confirmed; in case 4 of acute monocytic leukemia, bone marrow necrosis followed intramedullary chemotherapy and in case 5, marrow necrosis was secondary to chronic granulocytic leukemia. These four manifestations mentioned above have not been reported yet at home. Three cases examined by systemic 99mTe bone scan suggest that 99mTe bone scan be useful in the diagnosis of marrow necrosis. In this paper, the causes, diagnosis, treatment, prognosis and pathogenesis are discussed.