Objective To evaluate the diagnostic value of dobutamine?stressed cardiac morphing ( CM) MPI ( CMMPI) for coronary artery disease ( CAD) in middle?aged patients. Methods A total of 97 middle?aged patients (52 males, 45 females, age 40-65 (52.98±7.74) years) from March 2011 to Febru?ary 2015 with chest distress, cardiopalmus and chest pain symptoms ( suspected CAD) were retrospectively studied. Informed consents were signed by patients before examination. All patients underwent one?day dobu?tamine?stressed/rest CMMPI and CAG within one month. The diagnostic value of CMMPI was assessed and compared with CAG. Results CMMPI revealed 42 abnormal cases and 9 normal cases in 51 cases with cor?onary artery stenosis by CAG. CMMPI found 11 abnormal cases and 35 normal cases in 46 cases with normal coronary artery by CAG. In comparison with CAG, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of CMMPI were 82.35%(42/51), 76.09%(35/46), 79.38%(77/97), 79.25%(42/53)and 79.55%(35/44) respectively. The side effect was slight and transient with an inci?dence of 82.47%(80/97). Conclusion The dobutamine?stressed CMMPI has an important value for the diagnosis of CAD and the assessment of myocardial damage in middle?aged patients.

Objective To evaluate the utility of multi-slice computed tomography (MSCT) in assessing acute non-reperfused myocardial infarct size. Methods Seven domestic pigs (mean weight 17.3 ± 1.9 kg) underwent ligation of the distal left anterior descending artery to establish a model of acute myocardial infarction (MI). MSCT and triphenyltetrazolium chloride (TTC) staining were performed two hours later. The following data were acquired and analyzed:MI volume (%), CT values of the infarcted region, left ventricular cavity and normal cardiac tissue at various scanning time-points (1, 5, 10, 15, 20 min after contrast injection). Results Using MSCT, the overall MI volume showed a time-dependent decrease, with a reduction of 28.87%after 20 min. The greatest reduction occurred at the 5 min time-point. In TTC staining, MI volume was 9.87%± 2.44%. When MI size, as determined by MSCT, was compared with that by TTC staining in Bland-Altman plots, there was a better agreement at 5, 10, and 15 min time-points at 1 and 20 min. Conclusions The study indicates that double-phase scanning examination using MSCT is a useful tool to assess MI size, and the optimal late-phase scanning time-point set within 5-15 min of contrast injection.

Objective To analyze the epidemiological characteristics of an outbreak of carbapenem resistant Klebsiella pneumoniae(CRKP)hospital infection in the neonatal intensive care unit(NICU),and to explore possible causes of the outbreak.Methods Case analysis,epidemiological studies and environmental detection methods were used to investigate the detection of CRKP in the NICU of a hospital from March 11,2022 to May 3,2022,and the causes and corresponding prevention and control measures were analyzed.Results This CRKP outbreak in the NICU occurred in two phases.The first phase was from March 11,2022,to March 30,2022,during which 3 people contracted CRKP hospital infections.The second phase was from April 13,2022,to May 3,2022,during which 4 people contracted CRKP hospital infections.The source of the hospital infection outbreak was patient No.1.All 13 CRKP cases showed sensitivity only to amikacin and tigecycline,with intermediate sensitivity to levofloxacin,and high resistance to other antibiotics.All 13 CRKP cases carried resistant genes for metalloenzymes.After the outbreak,the ward environment was sampled three times,with 35 samples taken in total,and 14 of them tested positive for CRKP.After strict environmental cleaning,disinfection,and multiple control measures,no new hospital infection cases similar to this outbreak were detected after May 13,2022.Conclusion The outbreak of NICU hospital infections may be due to the contamination of the ward environment,medical equipment,and inadequate hand hygiene of medical staff,leading to its spread.Therefore,strict cleaning and disinfection of the environmental surfaces,strengthening hand hygiene of medical staff,and implementing multiple measures can effectively control hospital infections of CRKP.

Objective To examine the associations between season of birth and factors as age at menarche,age at menopause and reproductive span.Methods A total of 285 186 female from the China Kadoorie Biobank,with complete data on critical variables and had menarche at 9-18 years old,were included.A total of 132 373 female with natural menopause were included for the analysis on age at menopause and reproductive span.Multiple linear regression models were used to assess the associations of birth season and the age at menarche,menopause,and reproductive span.Subgroup analyses were performed on birth cohorts and urban/rural residence.Results Compared with the Spring-born (March,April,and May),participants who were born in Summer (June,July,and August),Autumn (September,October,and November),and Winter (December,January,and February)appeared late on both age at menarche and menopause.Multivariable-adjusted coefficients (95％ CI)appeared as 0.14 (95％CI:0.13-0.16),0.26(95％CI:0.24-0.27),0.10 (95％CI:0.08-0.12) for age at menarche respectively and 0.14 (95％CI:0.08-0.20),0.18 (95％CI:0.12-0.24),0.09 (95％CI:0.03-0.16) for age at menopause respectively.No statistically significant association was found between the season of birth and reproductive span.The association was consistent between urban and rural residents and across the birth cohorts.Conclusions female born in spring showed both earlier age on both menarche and menopause,compared to the ones born in other seasons.Our findings suggested that exposures in early life with some degree of seasonal variation might influence the development of female reproductive system.

Objective:To study the expressions of heat shock protein (HSP) 90α and HSP90β in colorectal cancer and paracancer tissues, and to investigate the relationships between HSP90α, HSP90β and clinicopathological features of colorectal cancer patients, and to analyze their correlation.Methods:The tumor tissues and paracancer tissues of 117 patients with colorectal cancer were selected from the Department of Gastrointestinal Surgery, Third Affiliated Hospital of Shandong First Medical University from January 2016 to December 2020. The expression levels of HSP90α and HSP90β were detected by immunohistochemistry, and the relationships between the two proteins and clinicopathological features and the correlation of their expressions were analyzed.Results:The positive expression rates of HSP90α in colorectal cancer tissues and paracancer tissues were 74.4% (87/117) and 12.0% (14/117) , and there was a statistically significant difference ( χ2=92.83, P<0.001) . The positive expression rate of HSP90β in colorectal cancer tissues and paracancer tissues was 61.5% (72/117) and 10.3% (12/117) , and there was a statistically significant difference ( χ2=66.86, P<0.001) . The expression of HSP90α was correlated with tumor location ( χ2=8.67, P=0.003) , vascular invasion ( χ2=8.68, P=0.003) , lymph node metastasis ( χ2=8.52, P=0.004) , T stage ( χ2=21.07, P<0.001) , N stage ( χ2=11.94, P=0.003) , M stage ( χ2=5.37, P=0.020) , pathological stage ( χ2=25.64, P<0.001) . The expression of HSP90β was correlated with lymph node metastasis ( χ2=4.03, P=0.045) , T stage ( χ2=11.09, P=0.007) , N stage ( χ2=6.56, P=0.038) , M stage ( χ2=12.43, P<0.001) , pathological stage ( χ2=17.34, P=0.001) . There was a positive correlation between the expressions of the two proteins in colorectal cancer tissues ( r=0.42, P<0.001) . Conclusion:The expressions of HSP90α and HSP90β in colorectal cancer tissues are significantly higher than those in paracancer tissues, and they are related to lymph node metastasis and pathological stage. There is a positive correlation between the two proteins, which may be involved in the occurrence and development of colorectal cancer and are expected to become new tumor markers.

Inhibition of Mycobacterium tuberculosis (Mtb) cell wall assembly is an established strategy for anti-TB chemotherapy. Arabinosyltransferase EmbB, which catalyzes the transfer of arabinose from the donor decaprenyl-phosphate-arabinose (DPA) to its arabinosyl acceptor is an essential enzyme for Mtb cell wall synthesis. Analysis of drug resistance mutations suggests that EmbB is the main target of the front-line anti-TB drug, ethambutol. Herein, we report the cryo-EM structures of Mycobacterium smegmatis EmbB in its "resting state" and DPA-bound "active state". EmbB is a fifteen-transmembrane-spanning protein, assembled as a dimer. Each protomer has an associated acyl-carrier-protein (AcpM) on their cytoplasmic surface. Conformational changes upon DPA binding indicate an asymmetric movement within the EmbB dimer during catalysis. Functional studies have identified critical residues in substrate recognition and catalysis, and demonstrated that ethambutol inhibits transferase activity of EmbB by competing with DPA. The structures represent the first step directed towards a rational approach for anti-TB drug discovery.