[Analysis of lung cancer screening through low-dose spiral computed tomography among petroleum company staffs in Sichuan-Chongqing Area in 2020].

Objective: To provide scientific evidence for early lung cancer screening, to analyze the incidence of pulmonary nodules among petroleum company staffs in Sichuan-Chongqing Area. Methods: In January 2021 , 6002 petroleum company staffs in Sichuan-Chongqing Area which scanned by low-dose spiral computed tomography (LDCT) of chest in medical examination center in 2020 were retrospectively collected as objects. Their imaging and clinical data were collected. χ(2) test was used to analyze the differences in the detection rates of lung nodules and suspected lung cancer nodules among workers in petroleum company staffs of different genders, ages and types of work. Results: Among the 6002 objects, 3853 (64.2%) were male and 2149 (35.8%) were female, with an average age of (47.25±12.13) years old. A total of 431 cases (7.2%) of pulmonary nodules and 57 cases (0.9%) of suspected lung cancer nodules were detected. 45 cases were followed up with surgical treatment, and 41 cases (91.1%) of lung cancer were diagnosed by postoperative pathology. There were significant differences in the detection rates of pulmonary nodules and suspected lung cancer nodules between different age groups (χ(2)=51.23, 18.81 , P<0.001). The detection rates of pulmonary nodules in the age groups 51-60 years old and ≥61 years old were higher than those in the age groups≤40 years old and 41-50 years old (P<0.05). The detection rate of suspected lung cancer nodules in the age group≥ 61 years old was higher than those in the age groups≤40 years old, 41-50 years old and 51-60 years old (P< 0.05) . And the detection rate of suspected lung cancer pulmonary nodules in oil workers was higher than that of ordinary workers (P<0.05) . Among female objects, the detection rate of pulmonary nodules in oil workers was higher than that in ordinary workers (χ(2)=8.09, P=0.004) . The detection rate of pulmonary nodules in oil workers aged ≥61 years old was higher than ordinary workers (χ(2)=37.94, P<0.001) . Among male objects, the detection rate of suspected lung cancer pulmonary nodules in oil workers was higher than that in ordinary workers (χ(2)=8.42, P=0.004) . The detection rates of suspected lung cancer pulmonary nodules in oil workers aged 51-60 years old and ≥61 years old groups were higher than those of ordinary workers (χ(2)=4.70, 8.74; P=0.030, 0.003) . Conclusion: LDCT is suitable for early lung cancer screening for petroleum company staffs. During the clinical screening process, LDCT should be used as a routine physical examination item for petroleum workers older than 51 years old.

Dietary alpha lipoic Acid improves body composition, meat quality and decreases collagen content in muscle of broiler chickens.

A total of 192 broiler chicks were used to evaluate the influence of dietary α-lipoic acid (ALA) on growth performance, carcass characteristics and meat quality of broiler chickens with the purpose of developing a strategy to prevent the occurrence of pale, soft, and exudative (PSE) meat and to improve the meat quality of broilers. At 22 d of age, birds were allocated to 4 ALA treatments (0, 400, 800, and 1200 ppm). The results showed that dietary ALA significantly decreased average feed intake (AFI), average daily gain (ADG), final live body weight (BW) and carcass weight (p<0.05), while no difference in feed conversion ratio (FCR) was detected among chickens fed with and without ALA. Abdominal fat weight significantly decreased (p<0.05) for broilers fed 800 and 1200 ppm ALA. However when calculated as the percentage of carcass weight there was no significant difference between control and ALA treatments. Meat quality measurements showed that dietary ALA regulated postmortem glycolysis and improved meat quality as evidenced by increased muscle pH and decreased drip loss of meat (p<0.05). Although ALA did not change the tenderness of meat as indicated by meat shear force, dietary ALA decreased collagen content and mRNA expression of COL3A1 gene (p<0.05). In conclusion, the results indicate that dietary ALA may contribute to the improvement of meat quality in broilers.

[Mission and vision of clinical research in bariatric and metabolic surgery].

Clinical research progress in bariatric and metabolism research had promoted the development in clinical practice. In U. S and Europe, pivotal scientific questions had been explored by clinical researchers, which brought the updating of guidelines, accumulation in key evidences, promotion of the consensus of metabolic benefits, following further development in scientific area. Compared to U. S and Europe, clinical practice in bariatric and metabolic surgery development in China started later. Clinical research in China just developed into initial phase with few achievements with high quality and breakthrough contribution. However, with wider practice, larger patient population and higher quality of surgery, clinical research in bariatric and metabolic surgery in China will go to a new stage through clinical research with standardized guidance, broad cooperation and clinical data digitalization and standardization.

Sequence variants in the bovine nucleophosmin 1 gene, their linkage and their associations with body weight in native cattle breeds in China.

The nucleophosmin (nucleolar phosphoprotein B23, numatrin) gene (NPM1, previously known as nucleophosmin/nucleoplasmin family, member 1) encodes a multifunctional nucleolar phosphoprotein that plays a crucial role in cell growth and homeostasis. Seven sequence variants (SVs) were identified in the coding region of bovine NPM1, five of which were in complete linkage disequilibrium. Eight different haplotypes were identified, of which two major haplotypes have a frequency of 23.2% and 20.4%. Three SVs were significantly associated with body weight in the Nanyang population as analysed at different ages. No significant association was detected between 18 combined genotypes and body weight at five different ages. Our results suggest that some polymorphisms in NPM1 are associated with body weight at some ages and may be used as candidates for marker-assisted selection and management in beef cattle breeding programmes.

LncNORAD interference inhibits tumor growth and lung cancer cell proliferation, invasion and migration by down-regulating CXCR4 to suppress RhoA/ROCK signaling pathway.

OBJECTIVE: Non-small cell lung cancer (NSCLC) accounts for the majority of lung cancer, with an unfavorable prognosis of 5-year survival rates. It is of great clinical significance to further search for more efficacious and novel targets for diagnosis and therapeutic strategies. This study aimed at clarifying the role of long non-coding RNA (lncRNA) NORAD in proliferation, invasion and migration and tumor growth of NSCLC. MATERIALS AND METHODS: In this study, mRNA levels of lncRNA NORAD were examined by RT-PCR. CCK-8 assay was applied to test cell viability. Furthermore, wound healing assay and transwell assay were performed to detect the migration and invasion of A549 cells, respectively. Immunohistochemistry was applied to assess the levels of CXC chemokine receptor (CXCR) 4 and CXC chemokine ligand (CXCL) 12. Mice models of NSCLC in vivo were exploited to further examine the potential role of NORAD in tumor growth. Key proteins related to Ras homolog gene family member A (RhoA) GTPase/Rho-associated kinase (RhoA/ROCK) pathway were determined by Western blot. RESULTS: NORAD has elevated the levels in NSCLC tissues and cells. NORAD interference dramatically inhibited tumor growth and suppressed A549 cell proliferation, migration and invasion by downregulating CXCR4 and CXCL12 expression. RhoA/ROCK signaling pathway was activated in NSCLC. CONCLUSIONS: This study revealed that the downregulation of lncRNA NORAD could slow down the progression of NSCLC by regulating CXCR4 and RhoA/ROCK signaling pathway.

Pre-slaughter transport, AMP-activated protein kinase, glycolysis, and quality of pork loin.

Numerous studies have revealed that pre-slaughter stress, like transport, increases the occurrence of pale, soft, and exudative (PSE) pork meat. The molecular mechanism underlying this phenomenon, however, is poorly defined. In this study, we investigated the effects of pre-slaughter transport and subsequent rest on energy metabolism, AMP-activated protein kinase (AMPK) activation, and glycolysis in postmortem pork loin. Results indicated that pre-slaughter transport accelerated ATP depletion, which led to lower energy status in postmortem muscle immediately post-exsanguination when compared with control. The lower energy status led to AMPK activation within 1h postmortem, subsequently increasing glycolysis, leading to rapid glycolysis and high incidence of PSE meat. Allowing pigs to rest after transport restored energy status in muscle ante-mortem. Higher energy status then prevented premature and rapid AMPK activation in postmortem muscle and lessened the negative effects of pre-slaughter transport on meat quality. AMPK regulated glycolysis in postmortem muscle, at least partially, through phosphorylation and activation of phosphofructose kinase-2, since fructose-2,6-diphosphate content, an allosteric activator of phosphofructose kinase-1, was well correlated with AMPK activation and glycolytic rate. This suggests that AMPK is a potential molecular target for the control of PSE incidence in pork.

Effects of dietary α-lipoic acid on glycolysis of postmortem muscle.

The effects of dietary α-lipoic acid (α-LA) on the pH value, AMP-activated protein kinase (AMPK) activation, and the activities of glycogen phosphorylase and pyruvate kinase in postmortem muscle were investigated. Eighteen C57BL/6J mice were fed diets containing 0%, 0.5%, and 1.0% α-LA. At the end of 2-week feeding trial, the mice were killed and longissimus muscles were sampled at 0-, 1-, and 24-h postmortem for pH determination and enzyme assay. The results showed that dietary α-LA treatment significantly slowed down the decrease of pH values in postmortem muscle. The ultimate pH values in postmortem muscle of mice receiving 0.5% and 1.0% α-LA treatments were 6.40 and 6.63, respectively, significantly higher than that (6.21) of no α-LA treatment (p<0.05). AMPK was activated at the early postmortem stage. Dietary α-LA can suppress the activation of AMPK in postmortem muscle. At 1- and 24-h postmortem, activities of AMPK were much lower in postmortem muscle of mice receiving 0.5% and 1.0% α-LA treatments than that with no α-LA treatment. Between these two dietary α-LA treatments, however, no difference in AMPK activity was observed, indicating that 0.5% dietary α-LA is enough to suppress AMPK in postmortem muscle. Similar to AMPK, glycogen phosphorylase activity was higher in the treatment without dietary α-LA than those with 0.5% and 1.0% dietary α-LA supplements. No difference in the activity of glycogen phosphorylase was observed between the 0.5% and 1.0% dietary α-LA treatments. Dietary α-LA had no significant influence on the activity of pyruvate kinase in postmortem muscle. All these results indicate that AMPK plays a role in glycolysis in postmortem muscle. Dietary α-LA supplementation can suppress the activation of AMPK in postmortem muscle, down-regulate the activity of glycogen phosphorylase, resulting in a higher ultimate pH values in postmortem muscle. Therefore, dietary α-LA supplementation is a potential way to reduce the incidence of pale, soft, exudative (PSE) meat.

[Establishment of two cell lines secreting monoclonal antibodies against pathogenic free-living amoeba in Shanghai].

Taking Naegleria australiensis, a species of pathogenic free-living amoeba (isolated in Shanghai in 1986), as antigen, two cell lines which provided potentially permanent source of monoclonal antibodies were established by lymphocytic hybridoma technique. The results of identification showed that: (1) the two cell lines could secret two different kinds of McAbs; (2) both of the McAbs were IgG (by gel diffusion); (3) McAbs produced in BALB/c mice were at high concentrations. One of them had a titer of > or = 1:8,192 and the other > or = 1:1,024 (by enzyme linked immunosorbent assay). A decline of the titers after purification by salting-out method was shown. One of the purified McAbs had a titer of > or = 1:2,024 and the other > or = 1:128. We have adopted two ways of recovering cryopreserved cells: ordinary recovering and "direct" recovering. The latter way was more practical because it could reduce the cycle of antibody production, and avoid contamination and chromosome variation. Experiments with different doses of cells revealed that, if the latter way was used, the optimal dose was 3 to 5 x 10(6) cells per mouse.

Leucine stimulates mammalian target of rapamycin signaling in C2C12 myoblasts in part through inhibition of adenosine monophosphate-activated protein kinase.

Mammalian target of rapamycin (mTOR) signaling is one of the main signaling pathways controlling protein synthesis. Leucine treatment upregulates mTOR signaling, which enhances protein synthesis; however, the mechanisms are not well understood. Herein, treatment of C2C12 myoblast cells with leucine enhanced the phosphorylation of mTOR and ribosomal protein S6 kinase. Leucine treatment also decreased the adenosine monophosphate/ATP ratio in myoblasts by 36.4 +/- 9.1% (P < 0.05) and reduced the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) alpha subunit at Thr172 (28.6 +/- 4.9% reduction, P < 0.05) and inhibited AMPK activity (43.6 +/- 3.5% reduction, P < 0.05). In addition, leucine increased the phosphorylation of mTOR at Ser2448 by 63.5 +/- 10.0% (P < 0.05) and protein synthesis by 30.6 +/- 6.1% (P < 0.05). Applying 5-aminoimidazole-4-carbox-amide 1-beta-d-ribonucleoside, an activator of AMPK, abolished the stimulation of mTOR signaling by leucine, showing that AMPK negatively controls mTOR signaling. To further show the role of AMPK in mTOR signaling, myoblasts expressing a dominant negative AMPKalpha subunit were employed. Negative myoblasts had very low AMPK activity. The activation of mTOR induced by leucine in these cells was abated, showing that AMPK contributed to mTOR activation. In conclusion, leucine stimulates mTOR signaling in part through AMPK inhibition. This study implicates AMPK as an important target for nutritional management to enhance mTOR signaling and protein synthesis in muscle cells, thereby increasing muscle growth.

The halothane gene, energy metabolism, adenosine monophosphate-activated protein kinase, and glycolysis in postmortem pig longissimus dorsi muscle.

The presence of the halothane gene results in PSE meat. However, the exact mechanisms linking the halothane gene and the incidence of PSE meat remain unclear. We hypothesize that the presence of the halothane gene accelerates energy consumption in postmortem muscle, which activates adenosine monophosphate-activated protein kinase (AMPK), leading to enhanced glycolysis and PSE meat. To test our hypothesis, energy status, AMPK activity, and glycolysis in the postmortem LM of the halothane gene carrier and halothane-negative pigs were compared. The results showed that the presence of the halothane gene accelerated energy depletion in postmortem muscle immediately after exsanguination, leading to rapid and early depletion of ATP, as shown by an increase in the (adenosine monophosphate + inosine monophosphate):ATP ratio in postmortem LM. In addition, an early AMPK activation was observed in LM from halothane carriers. The fructose-2,6-diphosphate concentration in postmortem LM was well correlated with AMPK activation. To be a potent stimulator of phosphofructose kinase, the increase in fructose-2,6-diphosphate is expected to activate phosphofructose kinase, a key enzyme controlling glycolysis, leading to enhanced glycolysis and early accumulation of lactic acid. In summary, this study showed that the presence of the halothane gene induced early energy depletion, which could be a primary reason causing AMPK activation, leading to accelerated glycolysis and an increased incidence of PSE meat. However, AMPK might also be activated by other mechanisms besides energy depletion, which warrants further studies.

Effect of dietary alpha-lipoic acid on growth, body composition, muscle pH, and AMP-activated protein kinase phosphorylation in mice.

The effects of alpha-lipoic acid (ALA) on the growth, body composition, postmortem AMP-activated protein kinase (AMPK) activation, and 24-h muscle pH were investigated. Thirty male C57BL/6J mice were fed diets containing 0, 0.5, or 1.0% ALA (DM basis). At the end of the 3-wk feeding trial, carcass weights decreased (P < 0.05) 14 and 30% for mice fed 0.5 and 1.0% ALA, respectively, compared with the 0% group, with decreases in BW as the levels of dietary ALA increased. This change in carcass weight occurred because carcass fat content for mice receiving 0.5 and 1.0% ALA was 7.32 and 8.09% lower (P < 0.05), respectively, than for the 0% ALA treatment, and because gonadal fat decreased (P < 0.05) 85% in mice fed 1.0% ALA compared with those fed 0% ALA. Dietary ALA caused a slight increase (P < 0.05) in carcass moisture content, with no (P = 0.07) effect on protein and ash content. Furthermore, ALA supplement decreased (P < 0.05) ADFI (DM basis) from 4.3 g/d for 0% ALA-fed mice to 3.4 g/d for 1.0% ALA-fed mice. At 20 min postmortem, pH was greater (P < 0.05) in muscle of mice fed 1.0% ALA than in muscle of mice fed 0% ALA. Ultimate (24-h) pH values differed (P < 0.05) among treatments, and mean values were 5.83, 6.08, and 6.29 for 0, 0.5, and 1.0% ALA, respectively. Phosphorylation of AMPK alpha subunit at Thr172, an indicator of AMPK activation, was decreased (P < 0.05) in muscle of ALA-treated mice at 20 min postmortem. Because AMPK has a crucial role in the control of glycolysis, the reduction in AMPK activation decreases glycolysis, and thereby increases the ultimate pH of postmortem muscle. In summary, dietary ALA supplement can decrease fat accumulation in mice, and because ALA increased muscle pH at 20 min and 24 h postmortem, these results suggest that dietary ALA supplementation might decrease carcass fatness and prevent the development of PSE pork and poultry. However, further research is required to test the effects of ALA in swine and poultry.