Background Arsenic exposure has been demonstrated to induce apoptosis. The fibronectin type III structural domain 3B protein (FNDC3B) has been shown to promote cancer cell proliferation; however, its role in arsenic-induced apoptosis remains to be elucidated. Objective To investigate the effects of sodium arsenite (NaAsO₂) and its metabolites on the expression of FNDC3B gene in A549 cells and to understand the function of FNDC3B gene in A549 cells. Methods (1) A549 cells were exposed to varying final concentrations of NaAsO₂ and their optical density at 450 nm values were measured by Cell Counting Kit-8 (CCK-8) after 48 h. Survival curves were plotted, and a final exposure dose was selected according to the survival rate. Total protein and RNA were extracted by exposing A549 cells to high (30 µmol·L⁻¹), medium (20 µmol·L⁻¹), and low (10 µmol·L⁻¹) NaAsO₂ concentrations, high (30 µmol·L⁻¹) monomethylarsinic acid (MMA), and high (30 µmol·L⁻¹) dimethylarsinic acid for a period of 48 h. mRNA expression and the protein expression of the FNDC3B gene was detected by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot (WB), while the protein ubiquitination expression of the FNDC3B gene was detected by co-immunoprecipitation (CO-IP) and WB assay. (2) Knockdown of FNDC3B gene expression was achieved in A549 cells by siRNA interference. The si-FNDC3B fragment was transfected in A549 cells for 48 h. The mRNA and protein expression of FNDC3B gene was then detected by qRT-PCR and WB assay. Cell viability was determined through CCK-8 assay. Hoechst 33342/propidium iodide (PI) double staining and JC-1 mitochondrial membrane potential assay were employed to detect both early and late apoptosis, while cleaved caspase3 protein and P53 signalling pathway related protein expressions were evaluated by WB. Results (1) The CCK-8 results demonstrated a decline in the viability of A549 cells with an increase in NaAsO₂ concentration, with an inhibitory concentration at 50% of 38.12 µmol·L⁻¹. The qRT-PCR results demonstrated that compared to the control group, varying concentrations of NaAsO₂ (10, 20, and 30 µmol·L⁻¹) significantly upregulated the mRNA expression of FNDC3B gene (P<0.01). In contrast, MMA and DMA showed no significant effect on FNDC3B mRNA expression (P>0.05). The WB analysis revealed that the protein expression of FNDC3B was reduced in the NaAsO₂-treated group compared to the control, accompanied by elevated ubiquitination levels of FNDC3B protein, particularly at the K48 ubiquitination site. MMA and DMA exhibited no impact on FNDC3B protein expression. (2) Following the specific knockdown of FNDC3B expression in A549 cells, the CCK-8 assay demonstrated a significant reduction in cell viability in the silenced FNDC3B group (si-FNDC3B) compared to the control group. The JC-1 assay demonstrated that the mitochondrial membrane potential was diminished in the si-FNDC3B group relative to the control group. The Hoechst 33342/PI staining assay revealed that the si-FNDC3B group exhibited a notable degree of apoptosis. The si-FNDC3B group also displayed substantial apoptosis. The WB analysis indicated that the relative expressions of cleaved caspase3, P53, MDM2, Bad, and Bax proteins were elevated in the si-FNDC3B group in comparison to the control group. Conclusion The presence of NaAsO₂ is observed to promote the ubiquitination expression of the FNDC3B protein, which in turn reduces the expression of FNDC3B protein. However, the main metabolites DMA and MMA have no effect on the expression of FNDC3B. Furthermore, the silencing of FNDC3B is observed to inhibit the viability of A549 cells and promote apoptosis, a phenomenon related to the activation of P53 signaling pathway.

To screen new antigens for novel tuberculosis(TB)vaccine research,we used bioinformatics to predict the B and T cell epitopes of Rv2318,and evaluated the immunogenicity of Rv2318 and its T/B epitope peptides(Rv2318p).The recombinant plas-mids pET32a-Rv2318 and pET32a-Rv2318p were constructed through gene synthesis methods.The recombinant proteins were ex-pressed in a prokaryotic system and purified with nickel affinity chromatography.Proteins were identified with SDS-PAGE and western blotting.BALB/c mice were immunized subcutaneously with the recombinant proteins to evaluate immunogenicity.Sera were collected,and antigen specific antibody titers were evaluated with ELISA.Splenocytes were isolated,and cytokines and T cell proliferation were analyzed with ELISA and flow cytometry,respectively.Rv2318 included two epitope fragments,aa10-130 and 350-410.SDS-PAGE and western blotting indicated that the target proteins were expressed and purified correctly,and their relative molecular weights were-approximately 68 kD and 42 kD,respectively.Rv2318 and Rv2318p induced stronger humoral immune responses than observed in the control groups(P<0.000 1,n=6).Compared with Rv2318,Rv2318p showed significantly greater enhancement of specific IgG and IgG subclass antibodies(P<0.000 1,n=6).In addition,Rv2318p increased the ratio of IgG2a/IgG1,thus indicating that it primarily induced a cellular immune response biased toward the Th1 type.Cytokine experiments revealed that IFN-γ,IL-2,IL-6,and IL-4 significantly increased after immunization with Rv2318p(P all<0.01,n=6),particularly Th1 type cytokines(IFN-γ and IL-2).Furthermore,Rv2318 increased the expression of only IL-2 and IL-6,particularly IL-6(P all<0.01,n=6).Although Rv2318 in-duced more IFN-γ,we observed no significant difference between Rv2318 and PBS immunized mice.Importantly,Rv2318p stimu-lated mice to express IFN-γ at 842 pg/mL,approximately 3 times the level elicited by Rv2318.Whereas both proteins increased the proportions of CD4+and CD8+T cells,Rv2318p promoted greater proliferation of T lymphocytes.These data indicated that both Rv2318 and its epitope peptides enhanced humoral and cellular immune responses,whereas the epitope peptides notably triggered a stronger Th1 type cellular response.In conclusion,the recombinant protein Rv2318 and its epitope peptides showed favorable immunogenicity,and the immunogenicity of Rv2318p was superior to that of Rv2318.This study provides a theoretical basis for TB vaccine development.

This study was aimed at analyzing the epidemiological and drug resistance characteristics of tuberculosis at a desig-nated tuberculosis hospital in Hunan Province in 2024.Patients diagnosed with TB at the hospital between April and October 2024 were included in the study.Demographic data,clinical information,and drug sensitivity test results were collected from the hospital′s electronic medical record system.Descriptive statistics,the chi-square test,and logistic regression were used to analyze the epidemic characteristics,drug resistance characteristics,and factors influencing tuberculosis.Whole genome sequencing of isolates was per-formed,and lineage classification and drug resistance gene mutations were detected with TB-Profiler.The male-to-female ratio was 2.72∶1,and the median age was 56(IQR:43-66)years.Among the 391 patients,most were farmers(46.8%,183/391)and were pri-marily from Changsha(41.1%,162/391).Significant differences were observed in sex and occupation between pulmonary tuberculosis(PTB)and extrapulmonary tuberculosis(EPTB).The overall prevalence of any type of drug resistance of tuberculosis was 33.25%,and the multidrug resistance TB(MDR-TB)and poly-drug resistance(PR-TB)rates were 14.23%and 4.35%,respectively.The re-sistance rates to rifampicin(RIF),isoniazid(INH),ethambutol(EMB),and streptomycin(SM)were 17.90%,22.25%,6.39%,and 20.20%,respectively.Multivariable logistic regression analysis indicated that both diabetes(OR:2.295,95%CI:1.082-4.866)and retreatment(OR:17.822,95%CI:8.343-38.072)were risk factors for developing MDR-TB.Lineage 2(L2)strains accounted for 64.40%(136/191),whereas lineage 4(L4)accounted for 28.80%(55/191).The most common drug resistance mutations were katG Ser315Thr(62.50%,20/32)for INH,rpoB Ser450Leu(50.00%,12/24)for RIF,embB Met306Val(55.56%,5/9)for EMB,and rpsL Lys43Arg(80.95%,34/42)for SM.In conclusion,TB drug resistance was found to be a serious problem at a designated tu-berculosis hospital in Hunan in 2024.Strengthening the treatment and management of patients infected with L2 strains,those with co-morbid diabetes,and retreatment cases is crucial for preventing and controlling the emergence of drug-resistant TB.

To screen new antigens for novel tuberculosis(TB)vaccine research,we used bioinformatics to predict the B and T cell epitopes of Rv2318,and evaluated the immunogenicity of Rv2318 and its T/B epitope peptides(Rv2318p).The recombinant plas-mids pET32a-Rv2318 and pET32a-Rv2318p were constructed through gene synthesis methods.The recombinant proteins were ex-pressed in a prokaryotic system and purified with nickel affinity chromatography.Proteins were identified with SDS-PAGE and western blotting.BALB/c mice were immunized subcutaneously with the recombinant proteins to evaluate immunogenicity.Sera were collected,and antigen specific antibody titers were evaluated with ELISA.Splenocytes were isolated,and cytokines and T cell proliferation were analyzed with ELISA and flow cytometry,respectively.Rv2318 included two epitope fragments,aa10-130 and 350-410.SDS-PAGE and western blotting indicated that the target proteins were expressed and purified correctly,and their relative molecular weights were-approximately 68 kD and 42 kD,respectively.Rv2318 and Rv2318p induced stronger humoral immune responses than observed in the control groups(P<0.000 1,n=6).Compared with Rv2318,Rv2318p showed significantly greater enhancement of specific IgG and IgG subclass antibodies(P<0.000 1,n=6).In addition,Rv2318p increased the ratio of IgG2a/IgG1,thus indicating that it primarily induced a cellular immune response biased toward the Th1 type.Cytokine experiments revealed that IFN-γ,IL-2,IL-6,and IL-4 significantly increased after immunization with Rv2318p(P all<0.01,n=6),particularly Th1 type cytokines(IFN-γ and IL-2).Furthermore,Rv2318 increased the expression of only IL-2 and IL-6,particularly IL-6(P all<0.01,n=6).Although Rv2318 in-duced more IFN-γ,we observed no significant difference between Rv2318 and PBS immunized mice.Importantly,Rv2318p stimu-lated mice to express IFN-γ at 842 pg/mL,approximately 3 times the level elicited by Rv2318.Whereas both proteins increased the proportions of CD4+and CD8+T cells,Rv2318p promoted greater proliferation of T lymphocytes.These data indicated that both Rv2318 and its epitope peptides enhanced humoral and cellular immune responses,whereas the epitope peptides notably triggered a stronger Th1 type cellular response.In conclusion,the recombinant protein Rv2318 and its epitope peptides showed favorable immunogenicity,and the immunogenicity of Rv2318p was superior to that of Rv2318.This study provides a theoretical basis for TB vaccine development.

This study was aimed at analyzing the epidemiological and drug resistance characteristics of tuberculosis at a desig-nated tuberculosis hospital in Hunan Province in 2024.Patients diagnosed with TB at the hospital between April and October 2024 were included in the study.Demographic data,clinical information,and drug sensitivity test results were collected from the hospital′s electronic medical record system.Descriptive statistics,the chi-square test,and logistic regression were used to analyze the epidemic characteristics,drug resistance characteristics,and factors influencing tuberculosis.Whole genome sequencing of isolates was per-formed,and lineage classification and drug resistance gene mutations were detected with TB-Profiler.The male-to-female ratio was 2.72∶1,and the median age was 56(IQR:43-66)years.Among the 391 patients,most were farmers(46.8%,183/391)and were pri-marily from Changsha(41.1%,162/391).Significant differences were observed in sex and occupation between pulmonary tuberculosis(PTB)and extrapulmonary tuberculosis(EPTB).The overall prevalence of any type of drug resistance of tuberculosis was 33.25%,and the multidrug resistance TB(MDR-TB)and poly-drug resistance(PR-TB)rates were 14.23%and 4.35%,respectively.The re-sistance rates to rifampicin(RIF),isoniazid(INH),ethambutol(EMB),and streptomycin(SM)were 17.90%,22.25%,6.39%,and 20.20%,respectively.Multivariable logistic regression analysis indicated that both diabetes(OR:2.295,95%CI:1.082-4.866)and retreatment(OR:17.822,95%CI:8.343-38.072)were risk factors for developing MDR-TB.Lineage 2(L2)strains accounted for 64.40%(136/191),whereas lineage 4(L4)accounted for 28.80%(55/191).The most common drug resistance mutations were katG Ser315Thr(62.50%,20/32)for INH,rpoB Ser450Leu(50.00%,12/24)for RIF,embB Met306Val(55.56%,5/9)for EMB,and rpsL Lys43Arg(80.95%,34/42)for SM.In conclusion,TB drug resistance was found to be a serious problem at a designated tu-berculosis hospital in Hunan in 2024.Strengthening the treatment and management of patients infected with L2 strains,those with co-morbid diabetes,and retreatment cases is crucial for preventing and controlling the emergence of drug-resistant TB.

Background Arsenic is a human carcinogen. Arsenic and its metabolites affect the expression of p53, but whether there are any changes of p53 phosphorylation and ubiquitination levels in human bronchial epithelium cells (BEAS-2B) are not clear after exposure to arsenic and its metabolites. Objective To study the effects of arsenic and its metabolites monomethylarsic acid (MMA) and dimethylarsinic acid (DMA) on the expression of tumor suppressor gene p53 in BEAS-2B cells. Methods Different concentrations of sodium arsenite (NaAsO₂) were used to infect BEAS-2B cells, and the cell viability was detected with CCK-8 reagent to determine the dose and time of NaAsO₂ used for the following study. Based on the results of cell viability, the cells were divided into two panels: a sodium arsenide panel and an arsenic methylation metabolite penal. The doses of sodium arsenite were 0, 2, 4, and 6 μmol·L⁻¹ NaAsO₂; the arsenic methylation metabolite panel consisted of 0 μmol·L⁻¹ NaAsO₂ group (control), 6 μmol· L⁻¹ MMA group, 6 μmol· L⁻¹ DMA group， and 6 μmol· L⁻¹ NaAsO₂ group. The cells were collected after 48 h treatment, and the total protein and total RNA were extracted. The relative levels of p53 mRNA expression were determined by quantitative real-time polymerase chain reaction (qRT-PCR), the relative expression levels of p53 protein, p53 Ser9 and Ser15 phosphorylated proteins were determined by Western blot, and the level of p53 ubiquitination was detected by co-immunoprecipitation (CO-IP). Results Compared with the control group, the cell viability rates in all BEAS-2B cells treated by NaAsO₂ were significantly reduced (P<0.05), and the 50% cell viability was observed at 6 μmol·L⁻¹. Compared with the control group, the relative expression level of p53 mRNA gradually decreased after NaAsO₂ (2, 4, 6 μmol·L⁻¹) treatment (P<0.05), the relative expression levels of p53 protein and Ser9 phosphorylated protein induced by NaAsO₂ also decreased gradually (P<0.05), and the relative expression level of p53 Ser15 phosphorylated protein induced by NaAsO₂ followed the same pattern, but it was only lower than that of the control group in the 6 μmol·L⁻¹ NaAsO₂ group (P<0.05). Compared with the control group, there were no significant effects on the relative expression levels of p53 mRNA, p53 protein, Ser9 and Ser15 phosphorylated proteins in the MMA group and the DMA group. Compared with the control group, the expression level of p53 ubiquitination was significantly decreased and the expression of K48 ubiquitination decreased significantly after NaAsO₂ infection. Conclusion Arsenic causes a decrease in the expression of the p53 protein in BEAS-2B cells, largely due to inhibition of the phosphorylated pathway and a decrease in mRNA expression, and protein changes caused by a decrease in p53 ubiquitination do not play a dominant role. MMA and DMA do not affect p53 gene expression.

Objective:To evaluate the immunogenicity and protective effect of a multicomponent recombinant protein vaccine EPRHP014 constructed independently and provide a scientific basis for developing new tuberculosis (TB) vaccine and effective prevention and control of TB.Methods:Three full-length Mycobacterium ( M.) tuberculosis protein antigens (EsxH, Rv2628, and HspX) and two epitope-predicted and optimized epitope-dominant protein antigens (nPPE18 and nPstS1) were selected, from which five protein antigens were used to construct a protein antigen composition EPRHP014, including a fusion expression multi-component protein antigen (EPRHP014f) and a multi-component mixed protein antigen (EPRHP014m) formed with the five single protein using clone, purification, and purification respectively. Multicomponent protein vaccines EPRHP014f and EPRHP014m were prepared with aluminum adjuvant, and the BCG vaccine was used as a control. ELISA detected the titer of serum-specific antibodies, the secretion of various cytokines was detected by ELISpot and Luminex, and immune protection was observed by the M.tuberculosis growth inhibition test in vitro. The results were statistically analyzed by t-test or rank sum test, and P<0.05 was considered a statistically significant difference. Results:Mice Immunized with EPRHP014m and EPRHP014f could produce highly effective IgG antibodies and their subtypes IgG1 and IgG2a, and the antibody titers were similar to those of mice immunized with BCG, with no statistical significance ( P>0.05). The number of spot-forming cells (SFC) secreting IFN-γ and IL-4 induced by EPRHP014f group was significantly higher than those by EPRHP014m group and BCG group ( P<0.05), but there was no significant difference in the number of SFC for IFN-γ and IL-4 induced between EPRHP014m group and BCG group ( P>0.05). The secretion levels of GM-CSF and IL-12p70 induced by the EPRHP014m group were higher than those of the BCG group ( P<0.05), but there was no significant difference in the levels of IL-6 and IL-10 induced between EPRHP014m group and BCG group ( P>0.05). There was no significant difference in the secretions of IL-6, IL-10, IL-12, and GM-CSF between the EPRHP014f and BCG groups ( P>0.05). EPRHP014m group, EPRHP014f group, and BCG group had obvious antibacterial effects in vitro, and the difference was insignificant ( P>0.05). Conclusion:Both EPRHP014f and EPRHP014m can induce strong humoral and cellular immune responses in mice after immunization, and have a strong ability to inhibit the growth of M. tuberculosis in vitro, indicating that the antigen composition EPRHP014 has good potential in the development and application of TB vaccine.

Objective:To preliminarily evaluate the immunogenicity and efficacy of two novel tuberculosis vaccine candidates (a fusion multicomponent protein EPDPA015f and a mixed multicomponent protein EPDPA015m) and to provide a new antigen combination for the development of tuberculosis vaccines.Methods:Recombinant plasmids for the expression of EPDPA015f and EPDPA015m proteins were constructed. Six-week-old BALB/c mice were immunized with EPDPA015f or EPDPA015m in combination with aluminium adjuvant (50 μg/mouse) for three times with an interval of 10 d. The mice were sacrificed 10 d after the last immunization to collect blood and spleen samples. Serum antibody titers and cytokine levels were measured by ELISA, Luminex technique and enzyme-linked immunospot assay (ELISPOT). Mycobacterial growth inhibition assay (MGIA) was used to detect the ability of mouse splenocytes to inhibit the growth of Mtb in vitro. One-way analysis of variance and t-test were used for statistical analysis. Results:Both EPDPA015f and EPDPA015m could induce the production of various cytokines and IgG antibodies at a high level. The levels of cytokines related to Th1 (IL-2, TNF-α, IFN-γ), Th2 (IL-4, IL-6, IL-10) and Th17 (IL-17) as well as other proinflammatory cytokines (GM-CSF, IL-12) were higher in the EPDPA015f group than in the adjuvant group ( P<0.05). The titer of IgG antibody induced by EPDPA015f was as high as 1∶4×10 6. The results of MGIA showed that the numbers of Mtb (lgCFU) in the PBS, adjuvant, EPDPA015f and EPDPA015m groups were 3.46±0.11, 3.51±0.06, 2.98±0.09 and 3.19±0.08, respectively. The number of colonies in the EPDPA015f group was the least as compared with that in the other three groups ( P<0.001, P<0.001, P<0.01). Conclusions:The vaccine candidate EPDPA015f could elicit more comprehensive and high-level cellular and humoral immune responses, and exhibited superior in vitro inhibitory activity against the growth of Mtb. EPDPA015f had the potential to be used as a preventive vaccine or a booster vaccine

Objective: To investigate the pathogenic characteristics of viral encephalitis in children living in Hebei province. Methods: We randomly collected cerebrospinal fluid specimens from a total of 399 children diagnosed with viral encephalitis in Hebei Children′s Hospital from May to December 2017. Real-time fluorescence quantitative PCR and Sanger sequencing were used to detect viral nucleic acids in cerebrospinal fluid by an automatic laboratory station. Statistical analysis was performed on the experimental data using SPSS 21.0 software and the clinical data were analyzed. Comparison of infection rates of EV encephalitis in different months, using line × column chi-square test. The MRI and EEG positive rates of different viral encephalitis and viral encephalitis patients not infected with the virus were analyzed by Fisher′s exact probability test. The positive rate of infection with different viruses and non-virus agents was analyzed by Fisher′s exact probability test. Results: The result showed that 80 of 399 samples were positive, and the positive rate was 20.05%. It included 22 cases of enterovirus, 4 cases of influenza A virus, 3 cases of mumps virus, 2 cases of herpes simplex virus type 1, 1 case of herpes simplex virus type 2, 4 cases of EB virus, 7 cases of cytomegalovirus, 7 cases of herpes zoster virus, 8 cases of adenovirus, 14 cases of human herpesvirus type 6. Eight cases had combined viral infection. Eight cases had concurrent infections: 3 cases had enterovirus and herpesvirus type 6 concurrent infection, 1 case had enterovirus and Japanese encephalitis virus concurrent infection and 1 case had herpes simplex virus type 2 and adenovirus, 1 case had influenza A virus herpesvirus type 6, 1 case had mumps virus and herpesvirus type 6, 1 case had mumps virus and herpesvirus type 6, 1 case had herpes simplex virus type 1 and herpes zoster virus concurrent infections. Children with EV viral encephalitis in Hebei Province were highly prevalent in May and June (P=0.016). HHV6 virus encephalitis was more susceptible to infection than non-HHV6 virus (P=0.016); The rate of MRI positive findings in patients with different viral encephalitis was not statistically significant (P>0.05). The result of EEG of different viral encephalitis were P>0.05, which was not statistically significant. Conclusions EV was the most common pathogen of children with viral encephalitis in Hebei province. Encephalitis caused by influenza A virus cannot be ignored in clinical practice.

Objective To evaluate the changes of myocardial mechanics before and after percutaneous coronary intervention ( PCI ) in patients with acute myocardial infarction ( AM I ) by ultrasonic speckle tracking technique ,and investigate the recovery of left ventricular myocardium mechanics and the effects of common complications on the improvement of myocardial mechanics . Methods Sixty‐two patients with AM I were examined by echocardiography within 12 hours ,1 week and 3 months after PCI . According to the complications the patients were divided into simple AM I group ( 21 cases ) ,AM I with diabetes mellitus group ( 21 cases) ,and AM I with hypertension group ( 20 cases) . T hirty healthy volunteers were selected as control group . Conventional echocardiographic parameters and left ventricular strain parameters were evaluated in all subjects . Results ①Left ventricular end‐diastolic diameter ( LVEDD) ,left ventricular end‐systolic diameter ( LVESD) ,left ventricular end‐diastolic volume ( LVEDV ) ,and left ventricular end‐systolic volume ( LVESV ) in each AM I group before PCI were greater than the control group ( P ＜ 0 .05 ) ,left ventricular ejection fraction ( LVEF ) , global longitudinal and circumferential endocardial ( midcardial , epicardial) strain ,and left ventricular global radial strain were smaller than the control group ( P ＜0 .05) ;the global longitudinal and circumferential endocardial ( midcardial ,epicardial ) strain ,and left ventricular global radial strain in AM I with diabetes group were less than simple AM I group and AM I with hypertension group ( P ＜0 .05) ; the global longitudinal endocardial strain in AM I with hypertension group was less than simple AM I group ( P ＜0 .05) . ② The LVESV in the third month after PCI was less than that before and during 1 week after surgery ( P ＜ 0 .05 ) ,still greater than control group ( P ＜ 0 .05 ) . LVEF ,the left ventricular global longitudinal and circumferential endocardial( midcardial ,epicardial) strain , and left ventricular global radial strain were greater than those before and during 1 week after surgery ( P＜0 .05) ,still less than control group ( P＜0 .05) ; T here was no significant difference before PCI and during 1 week after PCI about routine and strain parameters ( P＞0 .05 ) . ③ T he degree of improvement of global longitudinal and circumferential endocardial strain in AM I with diabetes group were less than those in simple AM I group( P ＜0 .05) . T he degree of improvement of global longitudinal endocardial strain in AM I with hypertension group was less than that in simple AM I group ( P ＜0 .05) . Conclusions Patients with AMI have poor myocardial mechanics before PCI ,especially those with diabetes mellitus ; myocardial mechanics improves significantly 3 months after PCI ; diabetes mellitus or hypertension affectes the improvement of myocardial mechanics in patients with AM I after PCI .