[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.

[Effects of exosomes from human adipose-derived mesenchymal stem cells on inflammatory response of mouse RAW264.7 cells and wound healing of full-thickness skin defects in mice]

Objective: To investigate the effects of exosomes from human adipose-derived mesenchymal stem cells (ADSCs) on inflammatory response of mouse RAW264.7 cells and wound healing of full-thickness skin defects in mice. Methods: The experimental research methods were adopted. The discarded adipose tissue was collected from 3 female patients (aged 10-25 years) who underwent abdominal surgery in the First Affiliated Hospital of Air Force Medical University. ADSCs were extracted from the adipose tissue by collagenase Ⅰ digestion and identified with flow cytometry. Exosomes were extracted from the human ADSCs by differential ultracentrifugation, the morphology of the exosomes was observed by transmission electron microscopy, the particle diameter of the exosomes was detected by nanoparticle tracking analyzer, and the protein expressions of CD9, CD63, tumor susceptibility gene 101 (TSG101), and β-actin were detected by Western blotting. The human ADSCs exosomes (ADSCs-Exos) and RAW264.7 cells were co-cultured for 12 h, and the uptake of RAW264.7 cells for human ADSCs-Exos was observed. The RAW264.7 cells were divided into phosphate buffer solution (PBS) group stimulated with PBS for suitable time, endotoxin/lipopolysaccharide (LPS) stimulation 2 h group, LPS stimulation 4 h group, LPS stimulation 6 h group, LPS stimulation 12 h group, and LPS stimulation 24 h group stimulated with LPS for corresponding time, with 3 wells in each group, and the mRNA expressions of interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), IL-6, and IL-10 were detected by real-time fluorescence quantitative reverse transcription polymerase chain reaction (RT-PCR) method. The RAW264.7 cells were divided into PBS group, LPS alone group, and LPS+ADSCs-Exos group, with 3 wells in each group, which were dealt correspondingly for the time screened out in the previous experiment, the mRNA expressions of IL-1β, TNF-α, IL-6, IL-10, trasforming growth factor β (TGF-β,) and vascular endothelial growth factor (VEGF) were detected by real time fluorescence quantitative RT-PCR method, and the protein expressions of inducible nitric oxide synthase (iNOS) and arginase 1 (Arg1) were detected by Western blotting. Twenty-four 8-week-old male BALB/c mice were divided into PBS group and ADSCs-Exos group according to the random number table, with 12 mice in each group, and a full-thickness skin defect wound with area of 1 cm×1 cm was inflicted on the back of each mouse. Immediately after injury, the wounds of mice in the two groups were dealt correspondingly. On post injury day (PID) 1, the concentration of IL-1β and TNF-α in serum were detected by enzyme-linked immunosorbent assay, and the mRNA expressions of IL-1β, TNF-α, and IL-6 were detected by real time fluorescence quantitative RT-PCR method. On PID 3, 6, 9, 12, and 15, the wound healing was observed and the wound non-healing rate was calculated. On PID 15, the defect length of skin accessory and collagen volume fraction (CVF) were detected by hematoxylin eosin staining and Masson staining, respectively, the CD31 expression and neovascularization were detected by immunohistochemistry, and the ratio of Ki67 positive cells, the ratio of iNOS and Arg1 double positive cells, and the ratio of iNOS positive cells to Arg1 positive cells and their fluorescence intensities were detected by immunofluorescence method. The number of samples in animal experiments was 6. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and independent sample t test. Results: At 12 h of culture, the cells exhibited a typical spindle shape, which were verified as ADSCs with flow cytometry. The exosomes with a vesicular structure and particle diameters of 29-178 nm, were positively expressed CD9, CD63, and TSG101 and negatively expressed β-actin. After 12 h of co-culture, the human ADSCs-Exos were endocytosed into the cytoplasm by RAW264.7 cells. The mRNA expressions of IL-1β, TNF-α, IL-6, and IL-10 of RAW264.7 cells in LPS stimulation 2 h group, LPS stimulation 4 h group, LPS stimulation 6 h group, LPS stimulation 12 h group, and LPS stimulation 24 h group were significantly higher than those in PBS group (with t) values of 39.10, 14.55, 28.80, 4.74, 48.80, 22.97, 13.25, 36.34, 23.12, 18.71, 29.19, 41.08, 11.68, 18.06, 8.54, 43.45, 62.31, 22.52, 21.51, and 37.13, respectively, P<0.01). The stimulation 12 h with significant expressions of all the inflammatory factors was selected as the time point in the following experiment. After stimulation of 12 h, the mRNA expressions of IL-1β, TNF-α, IL-6, and IL-10 of RAW264.7 cells in LPS alone group were significantly higher than those in PBS group (with t values of 44.20, 51.26, 14.71, and 8.54, respectively, P<0.01); the mRNA expressions of IL-1β, TNF-α, and IL-6 of RAW264.7 cells in LPS+ADSCs-Exos group were significantly lower than those in LPS alone group (with t values of 22.89, 25.51, and 8.03, respectively, P<0.01), while the mRNA expressions of IL-10, TGF-β, and VEGF were significantly higher than those in LPS alone group (with t values of 9.89, 13.12, and 7.14, respectively, P<0.01). After stimulation of 12 h, the protein expression of iNOS of RAW264.7 cells in LPS alone group was significantly higher than that in PBS group and LPS+ADSCs-Exos group, respectively (with t values of 11.20 and 5.06, respectively, P<0.05 or P<0.01), and the protein expression of Arg1 was significantly lower than that in LPS+ADSCs-Exos group (t=15.01, P<0.01). On PID 1, the serum concentrations of IL-1β and TNF-α and the mRNA expressions of IL-1β, TNF-α, and IL-6 in wound tissue of mice in ADSCs-Exos group were significantly those in lower than PBS group (with t values of 15.44, 12.24, 9.24, 7.12, and 10.62, respectively, P<0.01). On PID 3, 6, 9, 12, and 15 d, the wound non-healing rates of mice in ADSCs-Exos group were (73.2±4.1)%, (53.8±3.8)%, (42.1±5.1)%, (24.1±2.8)%, and 0, which were significantly lower than (82.5±3.8)%, (71.2±4.6)%, (52.9±4.1)%, (41.5±3.6)%, and (14.8±2.5)% in PBS group, respectively (with t values of 4.77, 8.93, 5.54, 7.63, and 7.59, respectively, P<0.01). On PID 15, the defect length of skin accessory in wounds of mice in PBS group was significantly longer than that in ADSCs-Exos group (t=9.50, P<0.01), and the CVF was significantly lower than that in ADSCs-Exos group (t=9.15, P<0.01). On PID 15, the CD31 expression and the number of new blood vessels (t=12.99, P<0.01), in wound tissue of mice in ADSCs-Exos group were significantly more than those in PBS group, and the ratio of Ki67 positive cells was significantly higher than that in PBS group (t=7.52, P<0.01). On PID 15, the ratio of iNOS and Arg1 double positive cells in wound tissue of mice in PBS group was (12.33±1.97)%, which was significantly higher than (1.78±0.29)% in ADSCs-Exos group (t=13.04, P<0.01), the ratio of iNOS positive cells and the fluorescence intensity of iNOS were obviously higher than those of ADSCs-Exos group, and the ratio of Arg1 positive cells and the fluorescence intensity of Arg1 were obviously lower than those of ADSCs-Exos group. Conclusions: The human ADSCs-Exos can alleviate inflammatory response of mouse RAW264.7 cells, decrease macrophage infiltration and secretion of the pro-inflammatory cytokines, increase the secretion of anti-inflammatory cytokines to promote neovascularization and cell proliferation in full-thickness skin defect wounds of mice, hence accelerating wound healing.

Clinical judgement perplexed by initially undisclosed use of herbal medicine and unexpected cross-reactivity of immunoassay

We report a case of symptomatic bradycardia caused by consumption of a Chinese herbal medicine which was initially undisclosed to the attending emergency physician. The scientific name of the herb is Panax japonicus. Electrocardiogram revealed sinus bradycardia. Laboratory tests were normal except for the detection of a high serum digoxin level. Further interrogation of the patient eventually disclosed ingestion of the herb which, however, did not contain any digoxin. Other active ingredients in the herb include various types of ginsenoside. These are digoxin-like substances that had caused the observed false-positive detection of digoxin by fluorescence polarization immunoassay due to cross-reactivity. Our case-report provides an important insight about a blind-spot in the field of laboratory medicine (clinical pathology), namely, the false positive detection of digoxin due to crossreactivity in the immunoassay when we come across digoxin-like substances in clinical scenarios, which has barely received attention in the medical literature. It also conveys a clear educational message that with full understanding of the laboratory methodology and its mechanistic rationale there are actually some tricks-of-the-trade that allow us to optimize the specificity of the biochemical tests and the treatment of digoxin-like substances overdose.

Synthesis and analytical properties of a novel columnar metallomesogenic polymer

A metallomesogenic side-chain polymer with copper carboxylato discotic units in stacks prepared by covalent bonding of 14-pentadecenoic acid, stearic acid and poly(methylhydrosiloxane) is described. The physico-chemical and thermal properties of both monomeric and polymeric metallomesogens were determined by elemental analysis, IR, polarizing optical microscopy, thermal gravimetric analysis and differential scanning calorimetry. The polymeric states showed a discotic lamellar phase at 50-95 degrees C and an ordered discotic hexagonal phase at 95-200 degrees C. By dynamic coating, the metallomesogenic polymer was crosslinked to the capillary wall via benzoyl peroxide. The wall-coated capillary columns (15 m x 0.25 mm I.D.) were used for the separation of phenols. Factors affecting the retention and the sample selectivity were examined. Van 't Hoff plots as a function of temperature indicated that phase transitions were occurring. Thermodynamic properties of the analytes in this system were also studied. For the determination of a mixture of 3-aminophenol, 2-chlorophenol, 2-nitrophenol, 4-nitrophenol, o-methylphenol, m-methylphenol, p-methylphenol, 2,4-dichlorophenol, 2,4-dimethylphenol, 2,4-dinitrophenol, 2,4,6-trichlorophenol, 2,4,6-trimethylphenol, 4-bromophenol, 3-methyl-4-chlorophenol, pentachlorophenol, and unsubstituted phenol, the calibration graphs for most phenols were linear over the range of 10-1000 microg ml(-1) and the mass detection limits were in the ng range based on three times standard deviation of seven measurements of the lowest peak that could be detected.

The effect of DDB on dystrophic hamsters: an in vivo and in vitro study

Dimethyl-4, 4'-dimethoxy-5, 6, 5'-6'-dimethylenedioxybiphenyl-2, 2'-dicarboxylate (DDB) is a synthetic analogue of Schizandrin C, an active compound isolated from a Chinese herb, Fructus schizandrae. We administered this compound to dystrophic hamsters in vivo for 31 days. This led to a 61% reduction of the calcium content, an 86% reduction of the area of calcium deposits, and a 52% reduction of the area of necrosis of cardiac muscle. However, skeletal muscle necrosis was not significantly improved. No clear change in plasma creatine kinase (CK) was observed. In an in vitro incubation study, the rate of CK release and tetanus tension of the extensor digitorum longus muscle of dystrophic hamsters were not substantially changed by the addition of DDB. This study suggests that DDB has some effect on cardiac necrosis, and that it might be useful for treatment of the cardiac involvement in patients with muscular dystrophy or other conditions with accompaning Ca accumulation.

Pharmacological properties of Dibenzo[a,c]cyclooctene derivatives isolated from Fructus Schizandrae Chinensis III. Inhibitory effects on carbon tetrachloride-induced lipid peroxidation, metabolism and covalent binding of carbon tetrachloride to lipids

Fructus Schizandrae, a traditional Chinese tonic, has been shown to lower the elevated serum glutamic pyruvic transaminase (SGPT) levels of patients with chronic viral hepatitis and several of its components decrease the hepatotoxicity of carbon tetrachloride (CCl4) in animals. This paper deals with the mechanism of protection against CCl4-hepatotoxicity of these compounds as well as of DDB, a synthetic analogue of Schizandrin (Sin) C. Of the seven components, Sin B and C, Schizandrol (Sol) B, Schizandrer (Ser) A and B, as well as dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylenedioxy-biphenyl-2,2'-dicarboxylate (DDB) were shown to inhibit CCl4-induced lipid peroxidation and [14C]Cl4 covalent binding to lipids of liver microsomes from phenobarbital(PB)-treated mice. The compounds also decreased carbon monoxide (CO) production and cofactor (NADPH, oxygen) utilization during CCl4 metabolization by liver microsomes. It may be postulated, therefore, that the hepatoprotective effect of certain components isolated from Fructus Schizandrae as well as DDB is due to their inhibitory effect on CCl4-induced lipid peroxidation and the binding of CCl4-metabolites to lipids of liver microsomes.

Pharmacological properties of dibenzo[a,c]cyclooctene derivatives isolated from Fructus Schizandrae chinensis. II. Induction of phenobarbital-like hepatic monooxygenases

Schizandrin (Sin) A, B and C, Schizandrol (Sol) A and B and Schizandrer (Ser) A and B were isolated from Fructus Schizandrae chinensis, a traditional Chinese tonic. These components are the derivatives of dibenzo[a,c]cylooctene. Dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylenedioxy-biphenyl-2,2'-dicarboxylate (DDB) is an intermediate for synthesizing Sin C. The effect of these compounds on rat liver microsomal monooxygenases and epoxide hydrolase has been studied. Among these compounds, Sin B, Sin C, Sol B and DDB significantly increased rat liver cytochrome P-450 concentration, NADPH-cytochrome c reductase, benzphetamine and aminopyrene demethylase activities. The four compounds also markedly stimulated proliferation of smooth endoplasmic reticulum of liver cells. Metyrapone (1 mM) inhibited to a same extent (about 50%) the activity of aminopyrene demethylase of microsomes from rats treated by Sin B, Sin C, Sol B, DDB and phenobarbital (PB). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of liver microsomal preparations showed that Sin B and Sol B induce a major protein band of P-450 similar to that induced by PB. In addition, the effect of Sin B-, Sol B- and DDB-treated rat liver microsomes on [G-3H]-benzo[a]pyrene (BP) metabolism and covalent binding of reactive metabolites to DNA, in vitro, resembles that of PB. Dual induction of rats by Sol B and BP decreased mutagenicity of BP.

Pharmacological properties of dibenzo[a,c]cyclooctene derivatives isolated from Fructus Schizandrae chinensis. I. Interaction with rat liver cytochrome P-450 and inhibition of xenobiotic metabolism and mutagenicity

Seven compounds isolated from Fructus Schizandrae chinensis, a traditional Chinese tonic, which is also able to increase liver lesions by hepatoxic chemicals, are named Schizandrin (Sin) A, B and C, Schizandrol (Sol) A and B and Schizandrer (Ser) A and B. They are dibenzo[a,c]cyclooctene derivatives. Dimethyl-4,4'-dimethoxy-5,6,5',6'-dimethylenedioxy-biphenyl-2,2'-dicarboxylate (DDB) is an intermediate for synthesizing Sin C. The interactions of these compounds with rat liver microsomes in vitro have been investigated. Sol A and Sol B gave type I difference spectrum, the other six compounds gave 'reverse type I' difference spectrum. When Schizandrins or DDB were incubated with NADPH-reduced microsomes, Sin B, Sin C, Sol B, Ser A and Ser B generated dual Soret peaks of 455--460 nm and 425--430 nm, the other three compounds caused a difference spectrum without 455 nm peak. All these compounds more or less inhibit liver microsomal hydroxylation of benzo[a]pyrene (BP) demethylation of aminopyrine. Sin B, Sol B and DDB decreased mutagenicity of BP in Ames test.