Tissue Extracts From Infarcted Myocardium of Rats in Promoting the Differentiation of Bone Marrow Stromal Cells Into Cardiomyocyte-like Cells

Objective To investigate whether cardiac tissue extracts from rats could mimic the cardiac microenvironment and act as a natural inducer in promoting the differentiation of bone marrow stromal cells （BMSCs） into cardiomyocytes. Methods Three kinds of tissue extract or cell lysate [infarcted myocardial tissue extract （IMTE）, normal myocardial tissue extract （NMTE） and cultured neonatal myocardial lysate （NML）] were employed to induce BMSCs into cardiomyocyte-like cells. The cells were harvested at each time point for reverse transcription-polymerase chain reaction （RT-PCR） detection, immunocytochemical analysis, and transmission electron microscopy. Results After a 7-day induction, BMSCs were enlarged and polygonal in morphology. Myofilaments, striated sarcomeres, Z-lines, and more mitochondia were observed under transmission electron microscope. Elevated expression levels of cardiac-specific genes and proteins were also confirmed by RT-PCR and immunocytochemistry. Moreover, IMTE showed a greater capacity of differentiating BMSCs into cardiomyocyte-like cells. Conclusions Cardiac tissue extracts, especially IMTE, can effectively differentiate BMSCs into cardiomyocyte-like cells.

Degradable preformed particle gel as temporary plugging agent for low-temperature unconventional petroleum reservoirs:Effect of molecular weight of the cross-linking agent

The development of unconventional petroleum resources has gradually become an important succession for increasing oil production.However,the related engineers and researchers are paying more and more attention to the application of temporary plugging agents(TPAs)for their efficient development.TPAs can expand the stimulated reservoir volume(SRV)and facilitate the flow of oil and gas to the bottom of the well.Particle-gels used as temporary plugging agents have the characteristics of the simple injection process,good deformation,high plugging strength,and complete self-degradation performance,which have been widely applied in recent years.In this paper,five samples of DPPG polymerized by different molecular weights of cross-linking agents were prepared.In addition,infrared spectroscopy analysis,differential calorimetry scanning(DSC)analysis,static particle gel swelling and degradation performance evaluation experiments,and dynamic temporary plugging performance experiments in cores were conducted at 34°C.Results show that as the molecular weight of the cross-linking agent(at 0.01 g)in the DPPG molecule decreased from 1,000 to 200 Da,the fewer cross-linking sites of DPPG,the looser the microscopic three-dimensional mesh structure formed.The swelling ratio increased from 7 to 33 times.However,the complete degradation time increased from 40 to 210 min.Moreover,the DSC results confirmed that the higher the molecular weight of the cross-linking agent,the worse is chemical stability and the more prone it to self-degradation.DPPG samples had good temporary plugging performance in reservoir cores.DPPGs prepared by the cross-linking agent with smaller molecular weight has a stronger swelling ratio,higher gel strength,and greater plugging strength in the core permeabilities.Moreover,the degraded DPPG is less damaging to the cores.However,their slower degradation rates take a slightly longer times to reach complete degradation.The results of this paper can provide new ideas and a theoretical basis for the development of particle gel-type temporary plugging agents(TPA)with controllable degradation time in low-temperature reservoirs.It can help to expand the application range of existing DPPG reservoir conditions.

Evolution of blood lipids and risk factors of dyslipidemia among people living with human immunodeficiency virus who had received first-line antiretroviral regimens for 3 years in Shenzhen

Background:Lipid abnormalities are prevalent among people living with human immunodeficiency virus(HIV)(PLWH)and contribute to increasing risk of cardiovascular events.This study aims to investigate the incidence of dyslipidemia and its risk factors in PLWH after receiving different first-line free antiretroviral regimens.Methods:PLWH who sought care at the Third People’s Hospital of Shenzhen from January 2014 to December 2018 were included,and the baseline characteristics and clinical data during the follow-up were collected,including total cholesterol(TC),triglyceride(TG),low-density lipoprotein cholesterol(LDL-C)and high-density lipoprotein cholesterol(HDL-C).The risk factors of dyslipidemia after antiretroviral therapy were analyzed with the generalized estimating equation model.Results:Among the 7623 PLWH included,the mean levels of TC,HDL-C and LDL-C were 4.23±0.85 mmol/L,1.27±0.29 mmol/L and 2.54±0.65 mmol/L,respectively,and the median TG was 1.17(IQR:0.85-1.68)mmol/L.Compared with that in PLWH receiving tenofovir disoproxil fumarate(TDF)+lamivudine(3TC)+ritonavir-boosted lopinavir(LPV/r),zidovudine(AZT)+3TC+efavirenz(EFV),and AZT+3TC+LPV/r,the incidence of dyslipidemia was lower in PLWH receiving TDF+3TC+EFV.In multivariate analysis,we found that the risks of elevations of TG,TC,and LDL-C were higher with TDF+3TC+LPV/r(TG:odds ratio[OR]=2.82,95%confidence interval[CI]:2.55-3.11,P<0.001;TC:OR=1.24,95%CI:1.14-1.35,P<0.001;LDL:OR=1.06,95%CI:1.00-1.12,P=0.041),AZT+3TC+EFV(TG:OR=1.41,95%CI:1.28-1.55,P<0.001;TC:OR=1.43,95%CI:1.31-1.56,P<0.001;LDL:OR=1.18,95%CI:1.12-1.25,P<0.001),and AZT+3TC+LPV/r(TG:OR=3.08,95%CI:2.65-3.59,P<0.001;TC:OR=2.40,95%CI:1.96-2.94,P<0.001;LDL:OR=1.52,95%CI:1.37-1.69,P<0.001)than with TDF+3TC+EFV,while treatment with TDF+3TC+LPV/r was less likely to restore HDL-C levels compared with TDF+3TC+EFV(OR=0.95,95%CI:0.92-0.97,P<0.001).In addition to antiretroviral regimens,antiretroviral therapy duration,older age,overweight,obesity and other traditional factors were also important risk factors for dyslipidemia.Conclusion:The incidence of dyslipidemia varies with different antiretroviral regimens,with TDF+3TC+EFV having lower risk for dyslipidemia than the other first-line free antiretroviral regimens in China.

Alcohol dehydrogenase 5 of Helicoverpa armigera interacts with the CYP6B6 promoter in response to 2-tridecanone

Alcohol dehydrogenase 5(ADH5)is a member of medium-chain dehydro-genase/reductase family and takes part in cellular formaldehyde and S-nitrosoglutathione metabolic network.2-tridecanone(2-TD)is a toxic compound in many Solanaceae crops to defend against a variety of herbivory insects.In the broader context of insect development and pest control strategies,this study investigates how a new ADHS from Helicoverpa armigera(HaADH5)regulates the expression of CYP6B6,a gene involved in molting and metamorphosis,in response to 2-TD treatment.Cloning of the HaADH5 complementary DNA sequence revealed that its 1002 bp open reading frame encodes 334 amino acids with a predicted molecular weight of 36.5 kD.HaADH5 protein was purified in the Es-cherichia coli Transetta(pET32a-HaADH5)strain using a prokaryotic expression system.The ability of HaADH5 protein to interact with the 2-TD responsive region within the promoter of CYP6B6 was confirmed by an in vitro electrophoretic mobility shift assay and transcription activity validation in yeast.Finally,the expression levels of both HaADH5 and CYP6B6 were found to be significantly decreased in the midgut of 6th instar larvae after 48 h of treatment with 10 mg/g 2-TD artificial diet.These results indicate that upon 2-TD treatment of cotton bollworm,HaADHS regulates the expression of CYP6B6 by interacting with its promoter.As HaADH5 regulation of CYP6B6 expression may con-tribute to the larval xenobiotic detoxification,molting and metamorphosis,HaADH5 is a.candidate target for controlling the growth and development of cotton bollworm.