[Analysis on the relationship between cumulative high temperature exposure and steel workers' hypertension in a large steel mill].

Objective: To analyze the relationship between cumulative high temperature exposure and hypertension among steel workers. Methods: We conducted a survey among 7 660 production workers (7 023 males and 637 females) in a large steel mill during February-June 2017 and March-July 2018. Basic information, blood pressure, occupational history and high temperature data in workplace were collected through questionnaire survey, physical measurement and occupational exposure detection. Restrictive cubic spline model was used to analyze the dose-response relationship between cumulative high temperature exposure and hypertension, and the correlation between cumulative high temperature exposure and workers' hypertension was analyzed by logistic regression. Results: The median number of cumulative high temperature exposure was 626.56 ℃·year and 49.20% of workers were exposed to high temperature. The hypertension prevalence rate was 25.60% among the workers. According to the results of the spline model, the cumulative high temperature exposure was divided into three sections: <292.61, 292.61~<720.13, ≥720.13 ℃·year. Taking the exposure <292.61 ℃·year group as a reference, the risk of steel workers' hypertension in the 292.61~<720.13 ℃·year group and ≥720.13 ℃·year group is 1.44 and 2.17 times that of the reference group (P<0.05) . Conclusion: There was a nonlinear dose-response relationship between cumulative high temperature exposure and steelworkers' hypertension. With the increase of cumulative high temperature exposure, the risk of steelworkers' hypertension increases.

[Epidemiological investigation of 511 adult inpatients with gas burns].

Objective: To analyze the epidemiological characteristics of adult inpatients with gas burns in the Department of Burns of Hwa Mei Hospital of University of Chinese Academy of Sciences (hereinafter referred to as the author's unit) , so as to provide evidence for the prevention of gas burn. Methods: Medical records of all inpatients with flame burns admitted to the author's unit from January 2011 to December 2017 were collected. The percentage of adult inpatients with gas burns in total inpatients with flame burns in the same period, and their gender, age, injury season, accident place, burn severity, common compound injury, complication, population caliber, education, industry, as well as the pre-injury disease and prognosis of elderly inpatients with gas burns were retrospectively analyzed. In addition, the age, accident place, education, and industry of the floating population in the adult inpatients with gas burns were analyzed separately and compared with the total population of adult inpatients with gas burns in 7 years. Data were processed with chi-square test or Fisher's exact probability test (Monte Carlo algorithm). Results: During the 7 years, 1 490 inpatients with flame burns were admitted to the author's unit, among which 511 were adult inpatients with gas burns, accounting for 34.30%. The number of adult inpatients with gas burns increased gradually during the 7 years, but its percentage in the total inpatients with flame burns during the same period showed no significant difference (χ(2)=7.087, P>0.05). Among the 511 adult inpatients with gas burns (hereinafter referred to as the patients in this group), there were 315 males and 196 females, with a male/female ratio of 1.61 to 1.00, and the middle-aged patients were the most, up to 270 cases, accounting for 52.84%. The distribution of adult inpatients with gas burns during the 7 years was significantly different in gender and age (χ(2)=54.810, 27.832, P<0.01). Among the patients in this group, most were injured in summer, totally 251 cases, accounting for 49.12%, and the accident place was mainly at home, totally 388 cases, accounting for 75.93%. The distribution of adult inpatients with gas burns during the 7 years was significantly different in injury season (χ(2)=42.254, P<0.01), but not in accident place (χ(2)=6.782, P>0.05). The patients in this group were mainly with moderate burns (237 cases, accounting for 46.38%), and the distribution trend of burn severity of adult inpatients with gas burns was basically the same during the 7 years (χ(2)=19.680, P>0.05); 176 patients (34.44%) were accompanied by inhalation injury, and 30 patients (5.87%) were accompanied by blast injury of lung; post injury complications occurred in 20 patients (3.91%). In the elderly inpatients with gas burns, 44.44% (32/72) were accompanied by pre-injury basic diseases, and the proportion of death or unhealed reached 18.06% (13/72). Most of the patients in this group were permanent residents (358 cases, accounting for 70.06%) and received secondary education (304 cases, accounting for 59.49%), and the majority of them were engaged in manufacturing/construction (138 cases, accounting for 27.01%), self-employed business (90 cases, accounting for 17.61%), and catering (90 cases, accounting for 17.61%) industries. The distribution of adult inpatients with gas burns during the 7 years was significantly different in population caliber, education, and occupation (χ(2)=17.496, 29.898, 88.896, P<0.05 or P<0.01). Among the patients of this group, the floating population were mainly young (90 cases, accounting for 58.82%) and middle-aged (62 cases, accounting for 40.52%), with main accident place at home (97 cases, accounting for 63.40%), generally received secondary education (101 cases, accounting for 66.01%), and were mainly engaged in manufacturing/construction (71 cases, accounting for 46.41%), self-employed business (26 cases, accounting for 16.99%), and catering (20 cases, accounting for 13.07%) industries. Compared with the total adult inpatients with gas burns in 7 years, the floating population were younger, more injured in the workplace, and more concentrated in industry (χ(2)=42.924, 9.390, 27.819, P<0.01). Conclusions: Gas burn was the leading injury cause of inpatients with flame burns in the author's unit, which mainly occurred in summer and at home; the patients were mainly male, young and middle-aged, and permanent residents, most of which were with moderate burn, often accompanied by inhalation injury. Most of the patients were of secondary education, engaged in manufacturing/construction, self-employed business, and catering industries, among which the floating population were younger, more injured in the workplace, and more concentrated in industry. In order to prevent gas burn, we should pay more attention to the propaganda and education of gas safety among young and middle-aged men, floating population, retired old people and housewives, especially in summer, we should do a good job in gas safety inspection at home. In addition, we should urge enterprises to further strengthen the supervision of production safety.

MicroRNA-125a regulates proliferation and apoptosis of acute myeloid leukemia through targeting NF-κB pathway.

OBJECTIVE: To elucidate the influence of microRNA-125a on the biological behaviors of acute myeloid leukemia (AML) cells. MATERIALS AND METHODS: MicroRNA-125a mimic and negative control (NC) were constructed and transfected into AML cell line HL60, respectively. Cell viability of HL60 cells transfected with microRNA-125a mimic or NC was determined by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide) assay. Regulatory effects of microRNA-125a on enzyme activities of B-cell lymphoma-2 (Bcl-2), Bcl-xl, caspase-3, and caspase-9 in HL60 cells were quantified by a spectrophotometry. Changes in apoptosis and invasion of HL60 cells overexpressing microRNA-125a were detected by flow cytometry and transwell assay, respectively. Protein levels of cell cycle genes (cyclin B, cdc-2, mdm-2), pro-apoptotic gene p53 and anti-apoptotic gene Bcl-2 in HL60 cells transfected with microRNA-125a mimic or NC were assessed by Western blot. Finally, the mRNA levels of Bax, caspase-8, nuclear factor-κB (NF-κB), and c-myc in HL60 cells with microRNA-125a overexpression were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). RESULTS: MicroRNA-125a expression remarkably increased by transfection of microRNA-125a mimic into HL60 cells, suggesting its sufficient transfection efficacy. MTT assay revealed an inhibited viability after microRNA-125a overexpression. Transfection of microRNA-125a mimic markedly enhanced enzyme activities of caspase-3 and caspase-9, but reduced activities of Bcl-2 and Bcl-xl in HL60 cells than controls (p<0.05). Moreover, microRNA-125a overexpression elevated apoptotic rate as FCM data indicated. Transwell assay demonstrated a decrease in the invasive rate of HL60 cells overexpressing microRNA-125a. Western blot analyses revealed that cell cycle genes all downregulated by transfection of microRNA-125a mimic in HL60 cells. The protein level of p53 upregulated and Bcl-2 downregulated in HL60 cells overexpressing microRNA-125a (p<0.05). Furthermore, mRNA levels of pro-apoptotic genes Bax and caspase-8 were enhanced after microRNA-125a overexpression, while mRNA levels of NF-κB and c-myc were reduced (p<0.05). CONCLUSIONS: MicroRNA-125a inhibits proliferative and invasive potentials, arrests the cell cycle in the G2/M phase of AML cells by regulating the NF-κB pathway.

Complete sequence analysis of mitochondrial DNA of aplastic anemia patients.

This study was primarily undertaken to test the hypothesis that mitochondrial DNA (mtDNA) mutations may be associated with aplastic anemia (AA). We analyzed mtDNA sequences from 15 patients with AA. The samples were obtained from bone marrow, and patients' oral epithelial cells were collected for normal tissue comparison. Total DNA was amplified by PCR after extraction, and these segments were then sent for sequencing. The results were compared with those of oral epithelial tissues as well as mtDNA sequences in the revised Cambridge Reference Sequence (rCRS) database. We detected 61 heteroplasmic mutations in 11 genes, including those encoding NADH dehydrogenase (ND)1-2 and 4-6, tRNA glutamic acid (TRNE), ribosomal RNA (RNR) 1 and 2, cytochrome c oxidase (COX1), cytochrome b (CYTB), and tRNA glycine (TRNG); mutation rates were particularly high in ND2 (34.4%) and ND4 (21.3%) in the patients' mtDNA genomes. The products of these genes are involved in oxidation in the respiratory chain, and a large number of homoplasmic mutations were found. Interestingly, these 162 polymorphisms were mostly in the D-loop DNA structure (54.3%), in which numerous mutations associated with leukemia and myelodysplastic syndromes are found. We conclude that functional impairment of the mitochondrial respiratory chain induced by mutation may be an important reason for hematopoietic failure in AA patients.

[The combined treatment with surgery and chemotherapy: primary approach to small cell lung carcinoma (SCLC)].

Forty cases of small cell lung carcinoma (SCLC) treated with surgical and chemotherapeutic combined therapy were reported. There were 28 males and 12 females in the group, most with history of more than 2 months, ranging in age of 27-66 years old. Cough, bloody sputum, low fever and chest distress are the main clinical manifestation. The small cell undifferentiated carcinoma was confirmed by fiberbronchoscope examination and pathology in all patients. Single lobectomy was performed in 20 cases, lobectomy of the upper and middle lobe in 9 cases, (sleeve resection of the lobarbronchus in 3 cases), and total pneumonectomy in 7 cases. Two cases were of stage I, 18 were of stage II, and 20 were of stage IIIa. Twelve patients received chemotherapy after operation, and 28 patients underwent the "chemotherapy-operation-chemotherapy" treatment model. Adriamycin (or CDDP), cytoxan, vincristin, and dexomathasone were used for the chemotherapy procedure. The 1, 3, 5-year survival rate of chemotherapy after operation and chemotherapy-operation-chemotherapy group were 70%, 45%, 30.5% and 54%, 30% and 22%, respectively. It is demonstrated that the long-term survival rate could be elevated in SCLC patients treated with chemotherapy after surgical operation, and the chance of operation also could be elevated by preoperative chemotherapy. The resection rate was 93% in the preoperative chemotherapy group.

The enhancing effects of amastatin, phosphoramidon and captopril on the potency of [Met5]-enkephalin in rat vas deferens.

The enkephalin-inactivating enzymes in rat vas deferens were studied by using the relatively specific inhibitor of each enzyme. The results showed that the rat vas deferens, like the other three preparations, guinea-pig ileum, mouse vas deferens and striatal membranes of guinea-pig brain, which had been investigated previously, contained three distinct enkephalin-hydrolyzing peptidases. Additionally, the enkephalin-hydrolyzing aminopeptidase, endopeptidase-24.11 and peptidyl dipeptidase A in rat vas deferens were found to be inhibited maximally with 1 microM of amastatin, 1 microM of phosphoramidon and 1 microM of captopril, respectively. In contrast to these three enzymes, both L-tyrosyl-L-tyrosine-sensitive dipeptidyl aminopeptidase and D-phenylalanine-sensitive carboxypeptidase were suggested not to be involved significantly in the inactivation of exogenously given enkephalin in rat vas deferens. The characteristics of the enkephalin-degradative enzymes in rat vas deferens were discussed in terms of their similarities to and differences from those in the other preparations.