A decision tree model to distinguish between benign and malignant pulmonary nodules on CT scans.

OBJECTIVE: Chest computed tomography (CT) is increasingly being used to screen for lung cancer. Machine learning models could facilitate the distinction between benign and malignant pulmonary nodules. This study aimed to develop and validate a simple clinical prediction model to distinguish between benign and malignant lung nodules. PATIENTS AND METHODS: Patients who underwent a video thoracic-assisted lobectomy between January 2013 and December 2020 at a Chinese hospital were enrolled in the study. The clinical characteristics of the patients were extracted from their medical records. Univariate and multivariate analyses were used to identify the risk factors for malignancy. A decision tree model with 10-fold cross-validation was constructed to predict the malignancy of the nodules. The sensitivity, specificity, and area under the curve (AUC) of a receiver operatic characteristics curve were used to evaluate the model's prediction accuracy in relation to the pathological gold standard. RESULTS: Out of the 1,199 patients with pulmonary nodules enrolled in the study, 890 were pathologically confirmed to have malignant lesions. The multivariate analysis identified satellite lesions as an independent predictor for benign pulmonary nodules. Conversely, the lobulated sign, burr sign, density, vascular convergence sign, and pleural indentation sign were identified as independent predictors for malignant pulmonary nodules. The decision tree analysis identified the density of the lesion, the burr sign, the vascular convergence sign, and the drinking history as predictors of malignancy. The area under the curve of the decision tree model was 0.746 (95% CI 0.705-0.778), while the sensitivity and specificity were 0.762 and 0.799, respectively. CONCLUSIONS: The decision tree model accurately characterized the pulmonary nodule and could be used to guide clinical decision-making.

[Determination of chlorobenzene metabolite-p-chlorophenol in urine by solid phase extraction-gas chromatography].

Objective: A method to determine chlorobenzene metabolite-p-chlorophenol in urine by solid phase extraction-gas chromatography was established. Methods: In May 2021, the urine sample was hydrolyzed at 100 ℃ for 1.5 h with 2 ml concentrated hydrochloric acid. After cooling and filtering, the sample was enriched and purified by Oasis(®)MAX 6cc SPE column. Drip washing with 0.01 mol/L hydrochloric acid solution and elution with acetonitrile, the eluent was volumized to 5 ml with acetonitrile and determined by gas chromatography, and quantify by standard curve method. Results: Calibration curve of the method was linear within the range of 1.61-80.30 µg/ml and showed good linearity with r=0.9997, the regression equation was y=1.51602x-0.10234. The determination limit was 0.17 µg/ml, and the limit of quantitation was 0.55 µg/ml. Recovery rates were between 89.3%-104.4%, the relative standard deviation (RSD) of intra-day measurements ranged from 4.3% to 6.7%, and the RSD of inter-day measurements ranged from 4.5% to 6.7%. Conclusion: This method could optimize sample pretreatment, and eliminate the interference of impurities, which is sensitive, efficient and accurate for the determination of chlorobenzene metabolite-p-chlorophenol in urine.

[Effects and mechanism of diammonium glycyrrhizinate on liver injury in severely scalded rats].

Objective: To investigate the effects and mechanism of diammonium glycyrrhizinate (DG) on liver injury in severely scalded rats. Methods: The experimental research method was used. Fifty-four female Sprague-Dawley rats aged 7-9 weeks were divided into sham injury group with simulated injury on the back, and simple scald group and scald+DG group with scald of 30% total body surface area on the back, with 18 rats in each group. Rats in sham injury group were not specially treated after injury, and rats in simple scald group and scald+DG group were rehydrated for antishock. Besides, rats in scald+DG group were injected intraperitoneally with 50 mg/kg DG at post injury hour (PIH) 1, 25, and 49. Rats in the three groups were collected, the serum content of liver function injury related indexes including aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), total protein, and albumin was measured by automatic biochemical assay analyzer, and serum content of ornithine carbamoyl transferase (OCT) was measured by enzyme-linked immunosorbent assay method at PIH 24, 48, and 72; hepatic histopathological changes at PIH 72 were observed by hematoxylin-eosin staining; the mRNA expressions of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), glucose regulated protein 78 (GRP78), activating transcription factor 4 (ATF4), and protein kinase R-like endoplasmic reticulum kinase (PERK) in liver tissue were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction at PIH 24, 48, and 72. The protein expressions of Bcl-2, Bax, GRP78, PERK, and ATF4 in liver tissue were detected by Western blotting at PIH 72 in sham injury group and PIH 24, 48, and 72 in simple scald group and scald+DG group. The number of samples was 6 in each group at each time point. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, and Bonferroni test. Results: Compared with that in sham injury group, the serum content of AST, ALT, and LDH was significantly increased (P<0.01), and the serum content of total protein and albumin was significantly decreased (P<0.05 or P<0.01) of rats in simple scald group at all post-injury time points. Compared with those in simple scald group, the serum AST content of rats in scald+DG group at PIH 24 was decreased significantly (P<0.05); the serum AST, ALT, and LDH content of rats in scald+DG group at PIH 48 was decreased significantly (P<0.01), and the serum total protein content was increased significantly (P<0.01); the serum AST, ALT, and LDH content of rats in scald+DG group at PIH 72 was decreased significantly (P<0.01), and the serum total protein and albumin content was increased significantly (P<0.01). At PIH 24, 48, and 72, the serum OCT content of rats in simple scald group was (48.5±3.9), (40.8±2.4), and (38.7±2.0) U/L, which was significantly higher than (15.1±2.5), (15.7±2.6), and (16.4±3.7) U/L in sham injury group (P<0.01), and (39.0±4.5), (31.8±2.0), and (22.1±2.6) U/L in scald+DG group (P<0.05 or P<0.01). At PIH 72, the cells in liver tissue of rats in sham injury group had normal morphology and regular arrangement, with no obvious inflammatory cell infiltration; the cells in liver tissue of rats in simple scald group had disordered arrangement, diffuse steatosis, and moderate inflammatory cell infiltration; the cells in liver tissue of rats in scald+DG group arranged regularly, with scattered steatosis and a small amount of inflammatory cell infiltration. Compared with those in sham injury group, the Bcl-2 mRNA (P<0.05 or P<0.01) and protein expressions of liver tissue were significantly decreased, and the mRNA (P<0.01) and protein expressions of Bax were significantly increased in rats in simple scald group at PIH 24, 48, and 72. Compared with those in simple scald group, the mRNA (P<0.05) and protein expressions of Bax in liver tissue of rats in scald+DG group were decreased significantly at PIH 48; the mRNA (P<0.01) and protein expressions of Bax in liver tissue of rats in scald+DG group were significantly decreased, and the mRNA (P<0.01) and protein expressions of Bcl-2 were significantly increased at PIH 72. Compared with those in sham injury group, the mRNA (P<0.05 or P<0.01) and protein expressions of ATF4, GRP78, and PERK in liver tissue were significantly increased in rats in simple scald group at all post-injury time points. Compared with those in simple scald group, the mRNA (P<0.01) and protein expressions of ATF4 in liver tissue of rats in scald+DG group at PIH 48 were significantly decreased, and the mRNA (P<0.05 or P<0.01) and protein expressions of ATF4, GRP78, and PERK were significantly decreased in liver tissue of rats in scald+DG group at PIH 72. Conclusions: DG can effectively reduce the degree of liver injury in rats after severe scald, and the mechanism may involve alleviating endoplasmic reticulum stress and mitigating mitochondrial damage.

[Determination of chloroacetic acid in workplace air by silanization-gas chromatography].

Objective: A method to determine acrylic acid in workplace air was developed by silanization-gas chromatography. Methods: In March 2020, chloroacetic acid in air were absorbed by silica gel tube, the samples were dried, then were desorbed and silanized by acetonitrile: N, O-bis (trimethylsilane) trifluoroacetamide (2∶1, V/V) at room temperature, allowed quantitative analysis of chloroacetic acid as its silanization product by gas chromatography. Results: Calibration curve of the method was linear within the range 0-162.8 µg/ml and showed good linearity with linear equation: y=0.011 8x, r=0.999 7. The determination limit of the method was 0.8 µg/ml, and the minimum detection concentration was 0.05 mg/m(3) (collect 15 L air) . The relative standard deviation (RSD) was 0.5%-1.3% (n=5) . Recoveries were between 98.6%-101.2%. Conclusion: The results prove silanization-gas chromatography is an accurate, simple and high sensitive method for determining chloroacetic acid in workplace air.

Comparison of clinical diagnostic value of spiral CT with different dose in patients with early-stage peripheral lung cancer.

PURPOSE: To compare the clinical diagnostic value of spiral CT scan with different dose in patients with early-stage peripheral lung cancer. METHODS: A total of 163 cases of patients with early-stage peripheral lung cancer who came to People's Hospital of Rizhao for treatment from June 2014 to January 2017 were retrospectively analyzed. A total of 78 cases of patients who received low-dose CT scanning were the low-dose group, another 84 cases of patients who received routine dose CT scanning were the routine dose group. Multislice helical CT (MSCT) scanning was performed in both groups, with tube voltage of 120 kV. Tube current was 25 m A in the low-dose group and 250 m A in the routine dose group. In addition, a total of 80 patients with lobar pneumonia were added as the control group of diagnostic sensitivity, specificity and accuracy. Pathological diagnosis was taken as the gold standard to compare the diagnostic sensitivity, specificity and accuracy of the two groups. RESULTS: The image quality, nodules and signs of the two groups were compared, and the results of radiation dose of the two groups were compared. The diagnostic sensitivity, specificity and accuracy of the low-dose group were 82.05%, 87.50% and 84.81%, respectively. The diagnostic sensitivity, specificity and accuracy of the routine dose group were 85.71%, 86.25% and 85.97%, respectively. The diagnostic value of the two groups was not statistically significant (p > 0.05). However, the radiation dose in the low-dose group was significantly lower than that in the routine group. CONCLUSION: Low-dose MSCT scanning can meet the clinical requirements for imaging diagnosis of peripheral lung cancer, and can reduce the radiation dose of patients.

[Effects of early supplement of exogenous L-carnitine on renal function in severely scalded rats].

Objective: To explore the effects of early exogenous L-carnitine supplementation on renal function in severely scalded rats. Methods: According to the random number table, sixty-six adult female Sprague-Dawly rats were divided into healthy control group (n=6), scald alone group (n=30), and scald+ carnitine group (n=30). In the latter two groups, the rats were inflicted with full-thickness scald of 30% total body surface area on the back, and the lactated Ringer's solution was injected through the tail vein for resuscitation immediately after scald. At post injury hour (PIH) 1, rats in scald+ carnitine group were intraperitoneally injected with 100 mg/mL L-carnitine solution 400 mg/kg, while rats in scald alone group were intraperitoneally injected with the same volume of normal saline. Rats in these two groups were injected once every 24 hours thereafter. Six rats were taken from each of scald alone group and scald+ carnitine group to collect the renal tissue and abdominal aorta blood at PIH 6, 12, 24, 48, and 72, respectively. The serum content of total protein, albumin, urea nitrogen, creatinine, and cystatin C were determined by the automatic biochemical analyzer. Renal tissue was stained with hematoxylin-eosin to observe histopathological changes. Rats in healthy control group did not undergo any treatment, and their renal tissue and blood sample were extracted and analyzed in the same way as those of severely scalded rats. Data were statistically analyzed with one-way analysis of variance and Bonferroni method. Results: (1) The serum content of total protein and albumin of rats in scald alone group at each time point after injury was significantly lower than that in healthy control group (P<0.05). The serum content of total protein of rats in scald+ carnitine group was significantly higher than that in scald alone group at PIH 12 and 24 (P<0.05), and the serum content of albumin of rats in scald+ carnitine group was significantly higher than that in scald alone group at PIH 12 (P<0.05). The serum content of total protein and albumin of rats in scald alone group and scald+ carnitine group showed a trend of decrease followed by an increase, with the lowest value at PIH 24. (2) The serum content of urea nitrogen and creatinine of rats in scald alone group at each time point after injury was significantly higher than that of healthy control group (P<0.05). The serum content of urea nitrogen of rats in scald+ carnitine group was significantly lower than that in scald alone group at PIH 6, 48, and 72 (P<0.05). The serum content of creatinine of rats in scald+ carnitine group was significantly lower than that in scald alone group at PIH 12, 24, 48, and 72 (P<0.05). The serum content of urea nitrogen and creatinine of rats in scald alone group and scald+ carnitine group showed a trend of increase followed by a decrease, with the peak value at PIH 12. (3) The serum content of cystatin C of rats in scald alone group at PIH 6, 12, 24, 48, and 72 was (0.250±0.030), (0.330±0.070), (0.300±0.060), (0.240±0.060), and (0.190±0.030) mg/L, and the content at the first 4 time points were significantly higher than (0.170±0.020) mg/L of healthy control group (P<0.05). At PIH 24, the serum content of cystatin C of rats in scald+ carnitine group was (0.210±0.040) mg/L, which was significantly lower than that of scald alone group (P<0.05). The serum content of cystatin C of rats in scald alone group and scald+ carnitine group showed a trend of increase followed by a decrease, with the peak value at PIH 12. (4) The renal tissue of rats in healthy control group was almost normal, and the degree of renal tissue injury of rats in scald+ carnitine group was lighter than that in scald alone group at each time point after injury. At PIH 24, the renal tissue of rats in scald alone group showed extensive swelling of the renal tubular epithelial cells, vacuolar degeneration and necrosis, loss of brush borders, and nuclear shrinkage; more than 2/3 of the renal tubular cell nuclei disappeared, the tubular lumen was narrowed, necrotic exfoliated cells could be seen in the lumen, and edema and inflammatory cell infiltration could be seen in the renal interstitial. Compared with those of scald alone group, significantly reduced severity of edema and necrosis of renal tubular epithelial cells, as well as less inflammatory cell infiltration were observed in the renal tissue of rats in scald+ carnitine group. Conclusions: Early supplement of L-carnitine in severely scalded rats can reduce the damage of renal cells, accelerate the restoration of the content of total protein, albumin, urea nitrogen, creatinine, and cystatin C, thereby maintaining the stability of renal function metabolism level.

[Establishment of a recombinase-aided isothermal amplification assay for nucleic acid detection of Echinococcus multilocularis and its preliminary application].

OBJECTIVE: To establish a rapid nucleic acid detection technique for identification of Echinococcus multilocularis based on the recombinase aided isothermal amplification assay (RAA) and assess its diagnostic efficiency. METHODS: The mitochondrial gene sequence of E. multilocularis (GenBank accession number: AB018440) was used as a target sequence. The primers were designed according to the RAA reaction principle and synthesized, and RAA was performed using the generated primers. E. multilocularis genomic DNA at various concentrations and the pMD19-T (Simple) vector containing various copies of the target gene fragment were amplified using RAA to evaluate its sensitivity for detection of E. multilocularis, and RAA was em- ployed to detect the genomic DNA of E. granulosus G1 genotype, Taenia saginata, T. asiatica, T. multiceps, Dipylidium caninum, Toxocara canis, Trichuris trichiura, Giardia lamblia, Fasciola hepatica, Paragonimus westermani, Fasciola gigantica and Clonorchis sinensis to evaluate its specificity. In addition, the optimized RAA was employed to detect nine tissue specimens of E. granulosus-infected animals, 3 fecal samples from E. granulosus-infected dogs and 2 fecal samples from field infected dogs to examine its reliability and feasibility. RESULTS: The established RAA was able to detect the specific target gene fragment of E. multilocularis within 40 min. The lowest detect limit of RAA was 10 pg if E. multilocularis genomic DNA served as a template. If the re- combinant plasmid was used as a template, the minimally detectable copy number of RAA was 104. In addition, RAA was nega- tive for the genomic DNA of E. granulosus G1 genotype, T. saginata, T. asiatica, T. multiceps, D. caninum, T. canis, T. trichiura, G. lamblia, F. hepatica, P. westermani, F. gigantica and C. sinensis. The established RAA was positive for detection of the tissue specimens of infected animals, and simulated and field dog stool samples. CONCLUSIONS: A rapid, sensitive and specific RAA is established, which shows promising values in identification of E. multilocularis and gene diagnosis of alveolar echinococcosis.

MiR-200c regulates apoptosis of placental trophoblasts in preeclampsia rats through Wnt/ß-catenin signaling pathway.

OBJECTIVE: To investigate the influence of micro ribonucleic acid 200c (miR-200c) on the apoptosis of placental trophoblasts in a rat model of preeclampsia (PE). MATERIALS AND METHODS: PE model in rats was established for extracting placental trophoblasts. Overexpression or knockdown of miR-200c was achieved by transfection of miR-200c mimics or inhibitor. Flow cytometry was carried out to detect the apoptotic rate of placental trophoblasts. Dual-luciferase reporter gene assay was performed to detect the interaction of miR-200c with WNT1. Western blotting was applied to determine the changes of protein levels in placental trophoblasts. RESULTS: The expression level of miR-200c in placental trophoblasts of PE group was significantly higher than that in control group. The apoptosis rate was (22.45 ± 2.62)%, (6.58 ± 1.28)%, and (9.57 ± 1.35)% in miR-200c mimic group, miR-200c inhibitor group, and control group, respectively, showing statistically significant differences. MiR-200c overexpression downregulated the expression level of anti-apoptotic protein B-cell lymphoma 2 (Bcl-2), but upregulated expression levels of apoptotic proteins Bcl-2-associated X protein (Bax) and active Caspase-3. MiR-200c suppressed WNT1 expression through the interaction with the 3'-untranslated region (3'-UTR) of WNT1. The expressions of WNT1 and ß-catenin were up-regulated after miR-200c overexpression, which was reversed by the Wnt/ß-catenin pathway activator. CONCLUSIONS: MiR-200c is involved in the development and progression of PE through the Wnt/ß-catenin signaling pathway.

[Characteristics of scar hyperplasia after burn and the rehabilitation treatment in children].

After the wound healing of deep burn in children, there will be scar tissue proliferation in varying degrees. Burn scar seriously affects the quality of life and the psychological health during the growth and development of children, so parents of children pay more and more attention to scar treatment and functional rehabilitation after burn. The treatment of scar after burn in children has become an important issue for medical workers in burn, plastic surgery, and rehabilitation. This article analyzes and summarizes the relationship between scar hyperplasia and age, race, and position of scar hyperplasia after burn in children. The treatment and functional rehabilitation methods of scar are also discussed, so as to provide some guidance for the formulation of appropriate individualized treatment plan.

[Effects of ω-3 polyunsaturated fatty acids on damage of intestinal mucosa of rats with severe burn in early stage and the mechanism].

Objective: To observe the effects of ω-3 polyunsaturated fatty acids (PUFA) on damage of intestinal mucosa of rats with severe burn in early stage and to explore the mechanism. Methods: One hundred and twenty SD rats were divided into sham injury group, pure burn group, and ω-3 PUFA group according to the random number table, with 40 rats in each group. Rats in sham injury group were sham injured, while rats in pure burn group and ω-3 PUFA group were inflicted with 30% total body surface area full-thickness scald (hereinafter referred to as burn) on the back. Rats in sham injury group and pure burn group were injected with normal saline solution (1 mL/kg) by tail vein, while rats in ω-3 PUFA group were injected with ω-3 PUFA solution (1 mL/kg) by the same way at 5 minutes post injury. At post injury hour (PIH) 3, 6, 12, 24, and 48, abdominal aorta blood and intestinal mucosa were collected from 8 rats in each group, respectively. Serum content of diamine oxidase (DAO) was detected by spectrophotography. Serum content of tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) was determined by enzyme-linked immunosorbent assay. Protein expression of NF-κB-p65 in intestinal mucosa was determined by Western blotting. Data were processed with analysis of variance of factorial design, one-way analysis of variance, chi-square test, LSD test, and Bonferroni correction. Results: (1) At all time points post injury, serum content of DAO of rats in pure burn group and ω-3 PUFA group was significantly higher than that in sham injury group (with P values below 0.01), and serum content of DAO of rats in ω-3 PUFA group was significantly lower than that in pure burn group (with P values below 0.01). (2) At all time points post injury, serum content of TNF-α and IL-6 of rats in pure burn group and ω-3 PUFA group was significantly higher than that in sham injury group (with P values below 0.01), and serum content of TNF-α and IL-6 of rats in ω-3 PUFA group was obviously lower than that in pure burn group (with P values below 0.01). (3) At all time points post injury, protein expressions of NF-κB-p65 in intestinal mucosa of rats in pure burn group and ω-3 PUFA group were significantly higher than those in sham injury group (with P values below 0.01). At PIH 3, 6, 12, 24, and 48, protein expressions of NF-κB-p65 in intestinal mucosa of rats in ω-3 PUFA group were 1.398±0.016, 1.999±0.948, 2.803±0.065, 1.739±0.602, and 1.484±0.645, obviously lower than 2.096±0.113, 3.402±0.189, 4.183±0.558, 3.618±0.408, and 2.614±0.775 in pure burn group (with P values below 0.01). Conclusions: The ω-3 PUFA may alleviate intestinal mucosa injury of rats with severe burn in early stage through reducing protein expression of NF-κB-p65 of intestinal mucosa, serum content of DAO, TNF-α, and IL-6, and inhibiting inflammatory response.

Induction of Salivary Gland-Like Cells from Dental Follicle Epithelial Cells.

The dental follicle (DF), most often associated with unerupted teeth, is a condensation of ectomesenchymal cells that surrounds the tooth germ in early stages of tooth development. In the present study, we aim to isolate epithelial stem-like cells from the human DF and explore their potential differentiation into salivary gland (SG) cells. We demonstrated the expression of stem cell-related genes in the epithelial components of human DF tissues, and these epithelial progenitor cells could be isolated and ex vivo expanded in a reproducible manner. The human DF-derived epithelial cells possessed clonogenic and sphere-forming capabilities, as well as expressed a panel of epithelial stem cell-related genes, thus conferring stem cell properties (hDF-EpiSCs). When cultured under in vitro 3-dimensional induction conditions, hDF-EpiSCs were capable to differentiate into SG acinar and duct cells. Furthermore, transplantation of hDF-EpiSC-loaded native de-cellularized rat parotid gland scaffolds into the renal capsule of nude mice led to the differentiation of transplanted hDF-EpiSCs into salivary gland-like cells. These findings suggest that hDF-EpiSCs might be a promising source of epithelial stem cells for the development of stem cell-based therapy or bioengineering SG tissues to repair/regenerate SG dysfunction.

The inhibition effect of expressions of miR-221 and miR-222 on glioma and corresponding mechanism.

PURPOSE: This study was designed to investigate the expressions of genes miR-221 and miR-222 in glioma cells and elucidate the mechanism of the inhibition of expressions of miR-221 and miR-222 in glioma. METHODS: After being cultured, in vitro cells of U251 malignant glioma were divided into five groups, namely, blank control group, nonsense sequence ODN transfection group, AS-miR-221-ODN transfection group, AS-miR-222-ODN transfection group, AS-miR-221 ODN and AS-miR-222 0DN co-transfection group. RESULTS: The growth of the cells in AS-miR-221/222 group was significantly inhibited after transfection of 24 hours. Moreover, this inhibition degree became more apparent with prolonged time. The cell percentage in AS-miR-221/222 transfection group was 57.2 % in G0/G1 phase, 35.1 % in S phase, and 38.2 % in G2/M phase. The cell percentage in S phase was decreased. Cell cycle arrest was found in G0/G1 phase. Animal experiments showed that the glioma volume of AS-miR-221/222 treatment group was significantly different to that of the control group (p < 0.05). Furthermore, this difference gradually increased with time. It reached the maximum at the end of the observation period. In the U251 glioma specimens in AS-miR-221/222 treatment group, local glioma tissue developed necrosis foci. In addition, the nuclear size, color, heteromorphism, and new vessel number of these glioma tissues were decreased. CONCLUSION: There are a series of abnormal miRNA expressions in glioma. Among them, miR-221 and miR -222 are clustered miR s with elevated expressions. The over-expressions of miR-221 and miR-222 can be considered as new molecular tags for human glioma (Tab. 5, Fig. 4, Ref. 30).