Association between combined exposure of heavy metals and biomarkers of early renal damage in occupational population / 中国职业医学

Objective: To investigate the effect of combined exposure to four heavy metals (lead, cadmium, arsenic, mercury) on early kidney injury in occupational population. Methods: A total of 384 workers exposed to combined heavy metals in a non-ferrous metal smelting plant in Guangdong Province were selected as the research subjects using judgment sampling method. The levels of blood lead, urinary cadmium and urinary arsenic were detacted by inductively coupled plasma mass spectrometry, while urinary mercury levels were measured using cold atomic absorption spectroscopy (acidic tin chloride reduction method). The levels of biomarkers such as urinary β2-microglobulin (β2-MG), kidney injury molecule-1 (Kim-1) and neutrophil gelatinase-associated lipocalin (NGAL) were detected by enzyme-linked immunosorbent assay. Spearman correlation analysis, linear regression, weighted quantile sum (WQS) regression and Bayesian kernel machine regression (BKMR) models were used to analyze the association between the exposure to the four heavy metals and early kidney injury biomarkers. Results: The median of blood lead, urinary cadmium, urinary arsenic and urinary mercury were 0.47 μmol/L and 4.450, 27.790 and 0.520 μg/gCr, respectively. The median of urinary β2-MG, Kim-1 and NGAL were 62.960, 1.130 and 18.150 μg/gCr, respectively. Spearman correlation analysis showed that urinary levels of β2-MG, Kim-1, and NGAL were weakly correlated with blood lead and urinary mercury levels (all P<0.01), but not correlated with urinary cadmium and urinary arsenic (all P>0.05). The results of multiple linear regression analysis showed that urinary mercury was positively correlated with urinary β2-MG, Kim-1 and NGAL (all P<0.01), urinary arsenic was positively correlated with urinary β2-MG level (P<0.01), and blood lead was negatively correlated with urinary β2-MG and Kim-1 (all P<0.05). The WQS regression analysis showed that the combined effect of the four heavy metals was positively correlated with urinary β2-MG, Kim-1 and NGAL (all P<0.01), with mercury having the highest impact and lead the lowest. BKMR model analysis showed the increasing trend in urinary β2-MG, Kim-1 and NGAL with the increasing levels of the combined exposure to the four heavy metals. Urinary β2-MG, Kim-1 and NGAL decreased when urinary mercury level increased from the 25th percentile to the 75th percentile and the other metals were correspondingly fixed at a certain level. When the blood exposure levels of other metals remained at the corresponding median levels, urinary β2-MG, Kim-1 and NGAL levels were positively correlated with urinary arsenic level, but no significant linear dose-response relationship was observed with the other three heavy metals. Conclusion: sLead, arsenic, and mercury are independently associated with early kidney injury biomarkers in occupational population from non-ferrous metal smelting. The four heavy metals had positive combined effects on urinary β2-MG, Kim-1 and NGAL, with mercury having the greatest impact.

Association between exposure to lead, cadmium, and arsenic and blood pressure in workers from a smelter / 环境与职业医学

Background Occupational exposure to lead, cadmium, or arsenic is a potential risk factor for blood pressure elevation. Current studies mainly focus on the relationship between a single metal and blood pressure. However, mixed metal exposure often exists in the actual working environment, and the interactive effects of polymetallic interactions on blood pressure and the dose-effect relationship remain unclear yet. Objective To explore the influence proportion of occupational exposure to lead, cadmium, or arsenic on blood pressure and their interactive effects. Methods From January to December 2021, workers from a smelter in southern China were selected. Demographic characteristics, height, weight, and blood pressure of workers were collected through questionnaire and physical examination. At the same time, their urine samples were collected and the levels of urinary lead, urinary cadmium, and urinary arsenic were detected by inductively coupled plasma mass spectrometry, and corrected by urinary creatinine (Cr). Linear regression and logistic regression were used to analyze the relationship between urinary lead, cadmium, and arsenic and blood pressure. Weighted quantile sum (WQS) regression was applied to evaluate the dose-effect relationship between urinary lead, cadmium, and arsenic exposures and blood pressure and the effect weight of each metal on blood pressure. Generalized linear regression and additive/multiplicative scaling were used to identify interactive effects of the three metals on blood pressure. Results A total of 1075 workers were included in this study, with a mean age of (44.68±5.11) years and mean working seniority of (24.66±5.23) years. There were 891 males (88.9%) and 184 were females (17.1%); 24.7% workers were drinkers and 45.7% workers were smokers; 302 workers (28.1%) reported hypertension and 37 of them were taking antihypertensive drugs. The P50 (P25, P75) levels of urinary lead, urinary cadmium, and urinary arsenic were 6.11 (3.71, 11.08), 3.88 (2.68, 5.44), and 26.04 (19.99, 35.11) μg·g−1, respectively. After adjusting for gender, age, working seniority, body mass index, smoking, drinking, and the usage of antihypertensive drugs, systolic and diastolic blood pressure increased by 0.772 and 0.418 mmHg respectively for 10% increase in lead, cadmium, and arsenic mixed exposure. Urinary cadmium, among the three single exposures, had the greatest effect on systolic and diastolic blood pressure, weight (w)=0.523 and 0.551 respectively. The interaction of urinary lead and urinary cadmium was positively correlated with the occurrence of hypertension, multiplicative interaction OR (ORint)=1.88 (95%CI: 1.09, 3.63), attributable proportion due to interaction (AP)=1.19 (95%CI: 0.40, 8.18). Conclusion This study shows that mixed exposure to lead, cadmium, and arsenic has a positive relationship with blood pressure, in which cadmium plays a major role. Co-exposure to lead and cadmium has a positive interactive effect on hypertension development and systolic blood pressure elevation.

Association of miR-146a rs2910164 G/C polymorphism with its abnormal expression and risk of gastric cancer / 中华医学遗传学杂志

OBJECTIVE@#To assess the influence of rs2910164 G/C single nucleotide polymorphism (SNP) of the miR-146a gene on its expression and susceptibility to gastric cancer.@*METHODS@#Fifty three gastric cancer patients and six gastric cancer cell lines were selected for determining the miR-146a expression by Taqman quantitative PCR. A model was constructed to assess the influence of miR-146a overexpression on the growth of AGS gastric cancer cells. A case-control study involving 417 gastric cancer patients and 420 cancer-free individuals was then conducted, and the allelic and genotypic frequencies of the rs2910164 G/C SNP were compared. The genotypes of all subjects were determined by using a Taqman allelic discrimination assay. A Taqman assay was also used to quantify mature and pri-miR-146a transcripts among 65 gastric cancer patients with known genotypes.@*RESULTS@#The expression of miR-146a was down-regulated among the 53 gastric cancer patients and six gastric cancer cell lines. Over-expression of miR-146a has suppressed the growth of gastric cancer by inhibiting the G1/S-phase transition of AGS cells. The case-control study showed that subjects with GC/CC genotypes had significantly lower risk for gastric cancer compared with those with GG genotype. In addition, miR-146a G/C SNP has significantly increased the level of mature miR-146a in those with GC/CC genotype compared with GG genotype.@*CONCLUSION@#Down-regulation of miR-146a may play an important role in the pathogenesis of gastric cancer. The rs2910164 polymorphism of the miR-146a gene may reduce the risk of gastric cancer by influencing the processing of mature miR-146a.

Clinical application of anatomy of blood vessel arches in ileum: Report of 45 cases / 中国医师杂志

ObjectiveTo observe anatomy of the blood vessel arches and their blood circulation in the ileum and further establish surgical strategy for preventing excessive tonicity and ischemia of the ileum after anastomosis of the ileum pouch and the anal canal.MethodsThe blood vessel arches were dissected in the ileum of 45 corpses and their blood circulation routes were observed.ResultsThe 2-tier blood vessel arches were found in 2 cases (4％), the 3-tier blood vessel arches in 35 cases (78％), the 4-tier blood vessel arches in 5 cases (11％), and the 5-tier blood vessel arches in 3 cases (7％).ConclusionsUnder the right colic artery, curing the superior mesenteric artery and vein can release the length of the small intestines, prevent tonicity and ischemia of the ileum after anastomosis of the ileum pouch and the anal canal, and supply enough blood to the ileum by the 2 -5 tier blood vessels.

Total proctocolectomy with SMA & V severance and ileal pouch-anal anastomosis for familial polyposis coli / 中华普通外科杂志

Objective To investigate the clinical value of a newly designed surgical therapy for familial polyposis coli by severing the superior mesenteric artery&vein in order to make a complete lysis of the mesentery and an ileum pouch and the anal anastomosis within the entire muscular sheath of the rectum.Methods Six patients with familial polyposis coli(5 males and 1 female,aged 24-36 years)were admitted and underwent the procedure which was consisted of:(1)An incision was made in the left middle and lower parts of the rectus abdominis;(2)The greater omentum was retained and the large intestine was removed;(3)At the juncture of the sigmoid colon and the rectum,the muscular sheath was dissociated 0.5cm,the mucous membrane of the rectum was stripped in a revolving manner,the nourishing artery and vein in the membrane were exposed,and clamped and cut in sequence up to the anocutaneoue line;(4)The rectal mucous membrane was completely removed;(5)Under the right colonic artery,the superior mesenteric artery and vein were severed;(6)An N-,J-or W-shaped pouch was made in the ileum accordingly:(7)An anastomosis of the ileum pouch and the anal canal was made within the entire muscular sheath of the rectum,and a drainage was placed;(8)The mesostenium was fixed on the fight posterior abdomen,the small intestines were spread out to the right side,and the mesostenium was covered on the coarse surface of the colon bed:(9)A tube was placed in the left lower abdomen for a vacuum aspiration for 2 days after operation,combined with the suction drainage,to eliminate the pelvic effusions;and(10)The abdomen was closed.Results Patients were able to discriminate stools and flatus 3-7 days after operation.and the formed stools occurred 7-10 days after operation.Five patients were followed-up for 3-17 years,with averagely one defecation a day,with no night defecation and seepage.Urination was normal;In another one patient who underwent the procedure 4 months ago the defecation was twice a day,with no night defecation.All the 6 patients had normal autonomic nerve function and sexual function as well as normal defecation and urination,with no recurrence of polyposis coli or infection.The small bowel functions well with no ischemia related symptoms.Conclusion Cutting the superior mesenteric artery and vein and then making anastomosis of the ileum pouch and the anal canal within the muscular sheath of the rectum is a new surgical approach to familial polyposis coli.It is safe and significantly improves the patients' life quality.