Objective To explore the impact of prolonged sitting on lumbar disc degeneration using MRI T1ρ and T2 mapping.Methods A total of 25 taxi drivers(prolonged sitting group)and 24 age-matched non-prolonged sitting volunteers(control group)underwent routine lumbar MRI,T1ρ,and T2 mapping.The differences of T1ρ and T2 values for different Pfirrmann grades of anterior annulus fibrosus(AAF),nucleus pulposus(NP),and posterior annulus fibrosus(PAF)were analyzed using Variance analysis,Spearman correlation test,and receiver operating characteristic(ROC)curve was drawn,with independent t-tests was used for between-group com-parisons.Results Statistically significant differences were observed in T1ρ and T2 values for all Pfirrmann Ⅰ-Ⅱ grades NP and Pfirrmann Ⅱ-Ⅳgrades AAF,NP,and PAF in both groups(P＜0.05).Both T1ρ and T2 values were negatively correlated with Pfirrmann grades.The area under the curve(AUC)of T1ρ values for NP at each Pfirrmann grade were 0.928,0.987,and 0.968,respectively,while the AUC of T2 values for NP were 0.777,0.966,and 0.975,respectively.The T1ρ and T2 values of L4/L5 NP and L5/S1 AAF,NP,and PAF were lower in the prolonged sitting group compared to the control group(P＜0.05).Conclusion T1ρ is superior to T2 mapping in detecting lumbar disc degeneration.Prolonged sitting is more likely to cause degeneration of L4/L5 and L5/S1 inter-vertebral discs.

Objective:To study the expression level of programmed death ligand 1 (PD-L1) in combined hepatocellular-cholangiocarcinoma (cHCC-CCA) and its correlation with the clinical characteristics and prognosis.Methods:The clinical data of 75 patients with cHCC-CCA undergoing surgery in Tianjin Medical University Cancer Institute and Hospital from January 2011 to December 2019, including 61 males and 14 females, with a median age of 55 years (36 to 77). Immunohistochemistry was conducted to determine the PD-L1 expression in tumor. The status of PD-L1 expression, clinicopathological data and prognosis of patients were analyzed.Results:In low-differentiated cHCC-CCA tissues, the proportion of PD-L1 expression (21.1%, 8/38) was higher than that in moderately to well-differentiated cHCC-CCA tissues (2.70%, 1/37, χ2=4.366, P=0.037). The median disease-free survival (DFS) and overall survival (OS)of PD-L1 positive patients were 12.3 and 15.1 months, respectively, lower than those of PD-L1 negative patients (14.4 and 23.3 months). The difference of DFS was statistically significant ( χ2=4.052, P=0.044). In multivariate analysis, major vascular invasion (DFS: HR=1.965, 95% CI: 1.119-3.450, P=0.019; OS: HR=1.781, 95% CI: 1.022-3.105, P=0.042) and lymph node metastasis (DFS: HR=2.451, 95% CI: 1.1033-5.814, P=0.042; OS: HR=2.652, 95% CI: 1.120-6.279, P=0.027) were identified as independent prognostic factors affecting DFS and OS. Conclusions:The proportion of PD-L1 positive is higher inthe low-differentiated cHCC-CCA tissue compared to that in moderately to well-differentiated cHCC-CCA. The major vascular invasion and lymph node metastasis are independent factors affecting the prognosis of patients with cHCC-CCA.

Objective:To explore the facilitators and barriers of weight self-management (WSM) in breast cancer patients, so as to provide reference for WSM intervention in breast cancer patients.Methods:This study was a descriptive qualitative study. From July to October 2021, 17 patients with breast cancer admitted to the Affiliated Hospital of Hebei University were selected as research objects by purposive sampling. Semi-structured interviews were conducted with patients. The data were analyzed by thematic analysis.Results:Two themes of WSM facilitators and barriers of breast cancer patients were extracted. Facilitators included three subthemes, namely: correct personal perception, positive self-regulation, positive social influence and social support. Barriers were composed of five subthemes, namely: lack of knowledge and skills, negative emotions, unhealthy living habits, role conflicts, limited physical functions.Conclusions:Medical and nursing staff should strengthen WSM health education for breast cancer patients, improve their awareness of WSM, self-regulation ability and symptom self-management, encourage them to exercise moderately, so as to promote the WSM level of breast cancer patients.

Objective:To investigate the distribution and antimicrobial resistance profile of clinical bacteria isolated from blood culture in China.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2016 to December 2017. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by US Clinical and Laboratory Standards Institute (CLSI) 2019. WHONET 5.6 was used to analyze data.Results:During the study period, 8 154 bacterial strains were collected from 33 hospitals, of which 2 325 (28.5%) were Gram-positive bacteria and 5 829 (71.5%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (34.7%), Klebsiella pneumoniae (15.8%), Staphylococcus aureus (11.3%), coagulase-negative Staphylococci (7.4%), Acinetobacter baumannii (4.6%), Pseudomonas aeruginosa (3.9%), Enterococcus faecium (3.8%), Streptococci (2.9%), Enterobacter cloacae (2.7%) and Enterococcus faecalis (2.5%). Methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus (MRCNS) accounted for 34.2%(315/922) and 77.7%(470/605), respectively. No vancomycin-resistant Staphylococcus was detected. The resistance rate of Enterococcus faecium to vancomycin was 0.6%(2/312), and no vancomycin-resistant Enterococcus faecium was detected. The ESBLs-producing rates in Escherichia coli, Klebsiella pneumoniae and Proteus were 55.7%(1 576/2 831), 29.9%(386/1 289) and 38.5%(15/39), respectively. The incidences of carbapenem-resistance in Escherichia coli, Klebsiella pneumoniae were 1.2%(33/2 831), 17.5%(226/1 289), respectively. The resistance rates of Acinetobacter baumannii to polymyxin and tigecycline were 14.8%(55/372) and 5.9%(22/372) respectively, and those of Pseudomonas aeruginosa to polymyxin and carbapenem were 1.3%(4/315) and 18.7%(59/315), respectively. Conclusion:The surveillance results from 2016 to 2017 showed that the main pathogens of blood stream infection in China were gram-negative bacteria, while Escherichia coli was the most common pathogen; the MRSA incidence was lower than other surveillance data in the same period in China; carbapenem-resistant Escherichia coli was at a low level during this surveillance, while carbapenem-resistant Klebsiella pneumoniae is on the rise.

Objective:To explore the feasibility and safety of minimally invasive surfactant administration (MISA) in preterm neonates with respiratory distress syndrome (NRDS).Methods:In this multicenter prospective randomized controlled trial, 92 preterm infants with gestation age ≤30 weeks and diagnosed with NRDS were enrolled in 8 level Ⅲ neonatal intensive care units (NICU) in Beijing-Tianjin-Hebei Region from 1 st July 2017 to 31 st December 2018. They were randomly assigned to minimally invasive surfactant administration (MISA) group or endotracheal intubation surfactant administration (EISA) group according to random number generated by computer. Infants in both groups received calf pulmonary surfactant preparation at a dose of 70-100 mg/kg. The data of demography, perinatal situation, medication administration, complications, clinical outcomes in the two groups were compared with Chi-square test, Student′s t-test, Mann-Whitney U test or Fisher′s exact test. Results:Among the 92 preterm infants, 53 were males, 39 were females; 47 were in the MISA group (25 males), and 45 were in the EISA group (28 males). The gestational age and birth weight were (29.5±1.2) weeks and (1 271±242) g in all patients, (29.5±1.4) weeks and (1 285±256) g in the MISA group, and (29.6±0.9) weeks and (1 255±227) g in the EISA group. The duration of surfactant infusion and the length of whole procedure in the MISA group were significantly longer than that in the EISA group (60 (18, 270) s vs. 50 (30, 60) s, Z=3.009, P=0.003; 90 (60, 300) s vs. 60 (44, 270) s, Z=3.365, P=0.001). For the outcomes, the incidence of hemodynamically significant patent ductus arteriosus (hsPDA) and bronchopulmonary dysplasia (BPD) were lower in the MISA group than in the EISA group (36% (17/47) vs. 67% (30/45), χ 2=8.556, P=0.003; 26% (12/47) vs. 47% (21/45), χ 2=4.464, P=0.035). Conclusions:Minimally invasive surfactant administration is applicable in preterm infants ≤30 weeks gestational age with NRDS. Although the length of whole procedure is longer than route endotracheal administration, the benefit of decreasing the incidences of hsPDA and BPD outweighs this demerit.

Radiation safety has been a focus of attention in the past few years. This review summarizes the researches related to the effective dose (ED) of PET/CT in recent years, including the ranges and influential factors of ED. In order to provide guidance in clinical practice, the common methods for estimating ED of PET/CT are also introduced.

Most diploid cells proliferate by proceeding through the canonical G1 (DNA pre-synthesis), S (DNA synthesis), G2 (DNA post-synthesis), and M(mitosis) phases of the cell cycle. However, there is another type of cell cycle that occurs frequently in both plants and animals, known as endoreplication. Endoreplication consists of alternating periods of G and S phases without cytokinesis, which results in polyploidy. It is indispensable for normal development, organ formation, and wound healing in humans. In recent years, con-siderable attention has been paid to delineating the connections of endoreplication with tumorigenesis and tumor progression. Here, we review the role of endoreplication in normal human development and discuss its possible role in tumor development and the un-derlying molecular mechanisms.

Objective:To investigate the inhibitory effect of Dickkopf-1 (Dkk1) on vasculogenic mimicry (VM) formation and the relevant mechanism. Methods:CD34-PAS dual staining and immunohistochemical staining were used to detect and analyze the re-lationship between VM existence and Dkk1 expression in 217 human colon cancer tissue samples;three dimensional (3D) culture was used to detect the influence of Dkk1 on tube structure formation and on VE-cadherin expression;a subcutaneous mouse xenograft mod-el was made to further validate the inhibitory role of Dkk1 on VM formation in vivo. Results:VM-positive samples indicated a lower expression of Dkk1(P<0.05);colon cancer cells with Dkk1 overexpression exhibited a decreased ability to form tube-like structure and a decreased expression of VE-cadherin;Dkk1 inhibited the VM-formation abilities of human colorectal carcinoma cell line xenograft tu-mor tissue. Conclusion:Dkk1 inhibits the VM formation of colon cancer.

Objective:To analyze the clinico-pathological characteristics, pathological diagnosis, and treatment of rhabdoid tu-mor. Methods:The medical records of four rhabdoid tumor patients that were admitted to the Tianjin Medical University Cancer Insti-tute and Hospital since 2000 were analyzed based on existing literature. Results:In one of the four cases, the tumor originated from the kidney, whereas in the other three, the tumor occurred from extra-renal soft tissues. Histologic analysis revealed that the tumor cells were loosely arranged with diffuse growth, vesicular nuclei, dyed cytoplasm, visible eosinophilic inclusions, and more nuclear fission. The results of immunohistochemical staining showed that the vimentin and epithelial membrane antigen were positive, whereas CK, CD99, CD34, and S-100 were positive at different degrees. MyoD1, Desmin, and INI-1 were negative. Conclusion:Rhabdoid tumor is rare and highly aggressive. It occurs mainly in the kidney and can also be found in other systems. The unique pathological form and im-munohistochemical staining observed on the tumor can be used as reference for diagnosis.

Given the unlimited proliferation and aerobic glycolysis in tumor cells, these cells require more glucose, glutamine, and other nutrients compared with normal cells. Tumor cells are often affected by insufficient nutrient supply. However, by sensing changes in the nutrient supply in tumor microenvironment and by regulating signal-transduction pathways, some specific proteins can help tumor cells in blocking the cell cycle, reprogramming metabolism, and regulating autophagy to progress and survive against nutri-ent stress. Exciting innovations have been made to elucidate the mechanisms relevant to this process. This review aims to highlight re-cent studies on the mechanisms of sensing the low nutrient supply in microenvironments, as well as the downstream effect factors in cancer cells.