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Polyphenol oxidase (PPO) is a metalloenzyme with a type III copper core that is abundant in nature. As one of the most essential enzymes in the tea plant (Camellia sinensis), the further regulation of PPO is critical for enhancing defensive responses, cultivating high-quality germplasm resources of tea plants, and producing tea products that are both functional and sensory qualities. Due to their physiological and pharmacological values, the constituents from the oxidative polymerization of PPO in tea manufacturing may serve as functional foods to prevent and treat chronic non-communicable diseases. However, current knowledge of the utilization of PPO in the tea industry is only available from scattered sources, and a more comprehensive study is required to reveal the relationship between PPO and tea obviously. A more comprehensive review of the role of PPO in tea was reported for the first time, as its classification, catalytic mechanism, and utilization in modulating tea flavors, compositions, and nutrition, along with the relationships between PPO-mediated enzymatic reactions and the formation of functional constituents in tea, and the techniques for the modification and application of PPO based on modern enzymology and synthetic biology are summarized and suggested in this article.
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Camellia sinensis , Catecol Oxidase/metabolismo , Oxirredução , CháRESUMO
BACKGROUND: Endoscopic evaluation in diagnosing and managing ulcerative colitis (UC) is becoming increasingly important. Several endoscopic scoring systems have been established, including the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score and Mayo Endoscopic Subscore (MES). Furthermore, the Toronto Inflammatory Bowel Disease Global Endoscopic Reporting (TIGER) score for UC has recently been proposed; however, its clinical value remains unclear. AIM: To investigate the clinical value of the TIGER score in UC by comparing it with the UCEIS score and MES. METHODS: This retrospective study included 166 patients with UC who underwent total colonoscopy between January 2017 and March 2023 at the Affiliated Hospital of Qingdao University (Qingdao, China). We retrospectively analysed endoscopic scores, laboratory and clinical data, treatment, and readmissions within 1 year. Spearman's rank correlation coefficient, receiver operating characteristic curve, and univariate and multivariable logistic regression analyses were performed using IBM SPSS Statistics for Windows, version 26.0 (IBM Corp., Armonk, NY, United States) and GraphPad Prism version 9.0.0 for Windows (GraphPad Software, Boston, Massachusetts, United States). RESULTS: The TIGER score significantly correlated with the UCEIS score and MES (r = 0.721, 0.626, both P < 0.001), showed good differentiating values for clinical severity among mild, moderate, and severe UC [8 (4-112.75) vs 210 (109-219) vs 328 (219-426), all P < 0.001], and exhibited predictive value in diagnosing patients with severe UC [area under the curve (AUC) = 0.897, P < 0.001]. Additionally, the TIGER (r = 0.639, 0,551, 0.488, 0.376, all P < 0.001) and UCEIS scores (r = 0.622, 0,540, 0.494, and 0.375, all P < 0.001) showed stronger correlations with laboratory and clinical parameters, including C-reactive protein, erythrocyte sedimentation rate, length of hospitalisation, and hospitalisation costs, than MES (r = 0.509, 0,351, 0.339, and 0.270, all P < 0.001). The TIGER score showed the best predictability for patients' recent advanced treatment, including systemic corticosteroids, biologics, or immunomodulators (AUC = 0.848, P < 0.001) and 1-year readmission (AUC = 0.700, P < 0.001) compared with the UCEIS score (AUC = 0.762, P < 0.001; 0.627, P < 0.05) and MES (AUC = 0.684, P < 0.001; 0.578, P = 0.132). Furthermore, a TIGER score of ≥ 317 was identified as an independent risk factor for advanced UC treatment (P = 0.011). CONCLUSION: The TIGER score may be superior to the UCIES score and MES in improving the accuracy of clinical disease severity assessment, guiding therapeutic decision-making, and predicting short-term prognosis.
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Colite Ulcerativa , Doenças Inflamatórias Intestinais , Humanos , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/terapia , Estudos Retrospectivos , Colonoscopia , Adjuvantes ImunológicosRESUMO
BACKGROUND: Smoldering multiple myeloma (SMM) is an asymptomatic plasma cell proliferative disorder that can progress to multiple myeloma (MM). Amyloidosis (light chain) (AL) is the most common form of systemic amyloidosis. There are few reports of SMM coexisting with AL involving the digestive tract. CASE SUMMARY: A 63-year-old woman presented with lower limb edema, abdominal distension, abdominal pain, and hematochezia. Gastroscopy showed gastric retention, gastric angler mucosal coarseness, hyperemia, and mild oozing of blood. Colonoscopy showed hyperemic and edematous mucosa of the distal ascending colon and sigmoid colon with the presence of multiple round and irregular ulcers, submucosal ecchymosis, and hematoma. Gastric and colonic tissue biopsy confirmed the diagnosis of AL by positive Congo red staining. MM was confirmed by bone marrow biopsy and immunohistochemistry. The patient had no hypercalcemia, renal dysfunction, anemia, bone lesions or biomarkers of malignancy defined as plasma cells > 60% in bone marrow. Additionally, no elevated serum free light chain ratio, or presence of bone marrow lesions by magnetic resonance imaging (SLiM criteria) were detected. The patient was finally diagnosed with SMM coexisting with AL. She received chemotherapy and was discharged when the symptoms were relieved. She is doing well at nearly five years of follow up. CONCLUSION: This case highlights that high index of suspicion is required to diagnose gastrointestinal AL. It should be suspected in elderly patients with endoscopic findings of granular-appearing mucosa, ecchymosis, and submucosal hematoma. Timely diagnosis and appropriate therapy can help to improve the prognosis of these patients.
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Background and aim: The molecular signatures of lung adenocarcinoma (LUAD) are not well understood. Centromere protein F (CENPF) has been shown to promote oncogenesis in many cancers; however, its role in LUAD has not been illustrated. We explored the role of CENPF in LUAD. Methods: CENPF expression level was investigated in public online database firstly, the prognosis of CENPF in LUAD were also assessed by Kaplan-Meier analysis. Then quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was performed using 13 matched pairs of clinical LUAD tissue samples. Subsequently, the impact of CENPF expression on cell proliferation, cell cycle, apoptosis, colony formation was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), flow cytometric analysis and colony formation assay, respectively. Finally, experimental xenograft lung cancer model of nude mice armpit of right forelimb to determine the effect of CENPF on LUAD tumorigenesis. Results: CENPF mRNA expression was significantly elevated in LUAD tissues compared with adjacent non-tumor lung tissues in Gene Expression Profiling Interactive Analysis (GEPIA) (P < 0.001). Up-regulated CENPF was remarkably positively associated with pathological stage, relapse free survival (RFS) as well as overall survival (OS) of LUAD patients. Besides, CENPF knockdown greatly suppressed A549 cell proliferation, induced S phase arrest, promoted apoptosis and decreased colony numbers of LUAD cells. Furthermore, knockdown of CENPF significantly inhibited the tumor growth of the LUAD cells in an experimental xenograft lung cancer model of nude mice armpit of right forelimb. Conclusion: Taken together, these results demonstrated that CENPF may serve as a potential biomarker of prognostic relevance and a potential therapeutic target for LUAD.
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Adenocarcinoma de Pulmão/genética , Biomarcadores Tumorais/genética , Proteínas Cromossômicas não Histona/genética , Neoplasias Pulmonares/genética , Proteínas dos Microfilamentos/genética , Recidiva Local de Neoplasia/epidemiologia , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/mortalidade , Adenocarcinoma de Pulmão/patologia , Animais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Proteínas Cromossômicas não Histona/análise , Proteínas Cromossômicas não Histona/metabolismo , Conjuntos de Dados como Assunto , Progressão da Doença , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Pulmão/patologia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Camundongos , Proteínas dos Microfilamentos/análise , Proteínas dos Microfilamentos/metabolismo , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/genética , Prognóstico , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Objective To explore whether aging increases severity of colitis in mice and its mechanism.Methods Young (6-8 weeks)and aged (56 weeks) C57Bl/6 mice were divided into the control and experimental group (n=5,each). Dextran sodium sulfate(DSS) was used to induce acute colitis mouse model in the experimental group.The mRNA expressions of tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6)in colon were measured by RT-PCR. Tight junctions (TJs) of intestinal epithelial cells was examined by transmission electron microscopy (TEM). Protein expressions of E-cadherin and occludin were detected by Western blotting and immunohistochemistry in colon.Results Compared with the young DSS-induced mice,the aged DSS-induced mice had more weight loss(t=3.679,P=0.006),higher disease indexes (t=2.496,P=0.037),higher histologic scores(U=0.000,P=0.008) and higher colonic IL-6 level (U=4.000,P=0.191). The TJs of intestinal epithelial cells were discontinuous in old healthy rats,and the TJs were destroyed significantly in both young and aged DSS-induced mice. Compared with the young DSS-induced mice,the aged DSS-induced mice had decreased protein expressions of E-cadherin (t=0.184,P=0.863)and occludin (t=0.399,P=0.710).Conclusions Aging leads to more severe disease following DSS challenge. Age-related deterioration in the functions of the gastrointestinal barrier and integrity may be one of the possible mechanisms.
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Colite , Mucosa Intestinal , Animais , Colo , Sulfato de Dextrana , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , RatosRESUMO
We investigated the association between single nucleotide polymorphisms (SNPs) in the fat mass and obesity associated (FTO) gene (rs9926289 A/G, rs79206939 A/G, rs9930506 A/G, rs8050136 A/C, and rs1588413 C/T) and polycystic ovary syndrome (PCOS), as well as outcomes of in vitro fertilization (IVF). A case-control study consisting of 147 PCOS patients and 120 healthy controls was conducted. FTO SNPs were genotyped by PCR to determine allelic frequencies, and IVF outcomes were analyzed. The results showed that FTO rs8050136 (p = .025) and rs1588413 (p = .042) were significantly associated with PCOS susceptibility, and women with risk alleles were often found to be obese (p < .05). For SNP rs8050136, women with AA + AC genotypes had higher body mass indexes (BMIs), oral glucose tolerance test/2 h (OGTT) levels and implantation rates but lower follicle-stimulating hormone (FSH) and human chorionic gonadotropin (hCG) day progesterone levels and ovulation numbers (all p < .05) than those with the CC genotype. For SNP rs1588413, women carrying risk alleles exhibited higher BMIs, implantation rate, and levels of luteinizing hormone (LH), estradiol, and OGTT/2 h (all p < .05) compared with those with non-risk genotypes. Therefore, these findings suggest that rs8050136 and rs1588413 are associated with PCOS susceptibility, and that women with risk alleles have less ovulation numbers but higher implantation rates than those with other genotypes.
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Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Fertilização in vitro/estatística & dados numéricos , Infertilidade Feminina/terapia , Síndrome do Ovário Policístico/genética , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Infertilidade Feminina/etiologia , Polimorfismo de Nucleotídeo Único , Gravidez , Adulto JovemRESUMO
BACKGROUND: Up to now, numerous case-control studies have reported the associations between fat mass and obesity associated (FTO) gene rs9939609 A/T polymorphism and polycystic ovary syndrome (PCOS), however, without a consistent result. Hence we performed current systematic review and meta-analysis to clarify the controversial results. METHODS: Case-control studies reporting the relationship of rs9939609 A/T polymorphism and PCOS published before April 2015 were searched in Pubmed database without language restriction. Data was analyzed by Review Manager 5.2. RESULTS: A total of five studies involving 5010 PCOS patients and 5300 controls were included for further meta-analysis. The results of meta-analysis showed that the FTO gene rs9939609 A/T polymorphism was significantly different between PCOS group and control group in different gene models (For AA + AT vs. TT: OR = 1.41, 95% CI = 1.28-1.55, P < 0.00001. For AA vs. AT + TT: OR = 1.54, 95% CI = 1.25-1.89, P < 0.0001. For AA vs. TT: OR = 1.74, 95% CI = 1.38-2.18, P < 0.00001. For A vs. T: OR = 1.36, 95% CI = 1.25-1.47, P < 0.00001, respectively) suggesting that A allele was a risk factor for PCOS susceptibility. Furthermore, subgroup analysis in Asian and Caucasian ethnicities also found significant association between rs9939609 A/T polymorphism and PCOS (In Asian subgroup: OR = 1.43, 95% CI = 1.29-1.59, P < 0.0001. In Caucasian subgroup: OR = 1.33, 95% CI = 1.08-1.64, P = 0.008) CONCLUSION: This meta-analysis suggests that rs9939609 A/T polymorphism of FTO gene is associated with PCOS risk, and that A allele is a risk factor for PCOS susceptibility simultaneously.
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Adiposidade/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato/genética , Obesidade/genética , Síndrome do Ovário Policístico/genética , Alelos , Povo Asiático/genética , Índice de Massa Corporal , Bases de Dados Factuais , Feminino , Predisposição Genética para Doença , Humanos , Obesidade/complicações , Síndrome do Ovário Policístico/complicações , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Sensibilidade e Especificidade , População Branca/genéticaRESUMO
DNA 3'-phosphatase takes an important role in DNA damage repair, replication and recombination. Here, we present a novel label-free fluorescent assay for T4 polynucleotide kinase/phosphatase (T4 PNKP) activity and its inhibitor screening by using poly(thymine)-templated fluorescent copper nanoparticles (CuNPs) as a fluorescent indicator. In this assay, we designed a simple T-rich hairpin primer with a 3'-phosphoryl end, which can serve as both the substrate for T4 PNKP and DNA template for the formation of fluorescent CuNPs. Once the phosphorylated hairpin primer was hydrolyzed by T4 PNKP, the resulting hairpin primer with a 3'-hydroxyl end was immediately elongated to form a long double-strand product by DNA polymerase, which prohibited the formation of fluorescent CuNPs due to the lack of poly T single-stranded DNA template. This new strategy provides a sensitive, selective, and cost-effective manner for T4 PNKP analysis, which holds a great potential in the study of DNA damage repair mechanisms.
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Cobre/química , Enzimas Reparadoras do DNA/antagonistas & inibidores , Enzimas Reparadoras do DNA/metabolismo , Avaliação Pré-Clínica de Medicamentos/métodos , Ensaios Enzimáticos/métodos , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Polímeros/química , Timina/química , Biocatálise , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Humanos , Nanopartículas Metálicas/química , FosforilaçãoRESUMO
mTOR, the mammalian target of rapamycin, is a conserved serine/threonine kinase which belongs to the phosphatidyl-linositol kinase-related kinase (PIKK) family. It has two complexes called mTORC1 and mTORC2. It is well established that mTOR plays important roles in cell growth, proliferation and differentiation. Over-activation of the mTOR pathway is considered to have a relationship with the development of many types of diseases, including polycystic ovary syndrome (PCOS) and ovarian cancer (OC). mTOR pathway inhibitors, such as rapamycin and its derivatives, can directly or indirectly treat or relieve the symptoms of patients suffering from PCOS or OC. Moreover, mTOR inhibitors in combination with other chemical-molecular agents may have extraordinary efficacy. This paper will discuss links between mTOR signaling and PCOS and OC, and explore the mechanisms of mTOR inhibitors in treating these two diseases, with conclusions regarding the most effective therapeutic approaches.
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OBJECTIVE: To observe the effect of moxibustion of "Dachangshu" (BL 25) on pain reaction and expression of transient receptor potential vanilloid 1 (TRPV 1) of bone marrow cells in visceral hyperalgesia (VHA) rats so as to explore its mechanism underlying visceral pain-relief. METHODS: Twenty-eight male SD rats were divided into control group, control+moxibustion group, VHA model and VHA+moxibustion group (n = 7/group). The VHA model was made by giving colorectal distension (CRD, 60 mmHg) to the newborn rats for 1 min (repeated once again in 30 min) from postnatal day 8 on, once daily for a week. Moxibustion was applied to ipsilateral "Dachangshu"(BL 25) area for 40 min from the 8th week on after birth. Abdominal withdrawal reflex (AWR) and pain threshold during CRD were measured before and after moxibustion. The TRPV 1 mRNA expressio of bone marrow cells was detected by real time-POR. RESULTS: (1) The AWR score of the model group was significantly higher than that of the control group, but the pain threshold of the model group was significantly lower than that of the control group (P < 0.01), suggesting a VHA in model rats. (2) After moxibustion, the AWR scores were significantly lower in the VHA+moxibustion group than in the model group (P < 0.05, P < 0.01), and the pain threshold was remarkably higher in the former group than in the latter group (P < 0.01). Similar results were found in the control+moxibustion group compared to the control group: the decreased AWR scores (CRD 40 mmHg, 60 mmHg and 80 mmHg, P < 0.01) and the increased pain threshold (P < 0.05). (3) The TRPV 1 mRNA expression level of bone marrow cells was significantly lower in the VHA + moxibustion group than in the model group (P < 0.01). No significant difference was found between the control and moxibustion+control groups in TRPV 1 mRNA expression level (P > 0.05). CONCLUSION: Moxibustion of "Dachangshu" (BL 25) can reduce visceral hyperalgesia and down-regulate TRPV 1 mRNA expression of bone marrow cells in VHA rats, suggesting an involvement of TRPV 1 mRNA of bone marrow cells in CRD-induced visceral pain development.
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Pontos de Acupuntura , Células da Medula Óssea/metabolismo , Hiperalgesia/genética , Hiperalgesia/terapia , Moxibustão , Limiar da Dor , Canais de Cátion TRPV/genética , Animais , Células Cultivadas , Colo/metabolismo , Colo/fisiopatologia , Modelos Animais de Doenças , Expressão Gênica , Humanos , Hiperalgesia/metabolismo , Hiperalgesia/fisiopatologia , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Canais de Cátion TRPV/metabolismoRESUMO
Recently, much work has been devoted to study MD-induced oncogenesis and the genes involved in this process. Among many genes in the MDV genome, several genes such as Meq, RLORF4, RLORF12, and 132bpr have been considered recently associated with virulence of MDV. In this paper, primers of Meq, RLORF4, RLORF12 and 132bpr genes were designed and synthesized, based on the published whole genome sequence of MDV strain GA. The genes of Meq, RLORF4 and RLORF12 from four Chinese epidemic MDV strains highly passaged on chicken embryo fibroblast (CEF), i. e. L-SYp85C, L-MSp75C, L-CZp75C, and L-ZYp75C, as well as their corresponding parent strains, i. e. L-SY, L-MS, L-CZ, and L-ZY, the reference virulent strain J-1 and the vaccine strain 814 were amplified by PCR respectively. Then the PCR products of interest were cloned and sequenced respectively. The results of sequence comparison and analysis of Meq genes in the study indicated that Meq genes from the two strains L-ZYp75C and L-CZp75C contained single nucleotide insertion and deletion. The Meq gene from strain L-ZYp75C contained an extra cytidine (C) insertion at nucleotide position 529 and a single thymidine (T) deletion at nucleotide position 602, resulting in a frameshift mutation. And this frameshift mutation could lead to changes in deduced amino acid sequence from position 177 to 200 of Meq gene. The extra C insertion at nucleotide position 625 in Meq gene of strain L-CZp75C was also predicted to cause frameshift mutation in three overlapping genes (Meq, RLORF6 and 23KD genes). The comparison of nucleotide sequences of RLORF4 genes in the study revealed that the RLORF4 gene of strain L-SYp85C contained a fragment deletion in Open Reading Frame (ORF) from nucleotide position 215 to 265, resulting in 17 amino acids deletions, which were not found in other sequenced strains. Comparison of nucleotide sequences of RLORF12 genes in the study revealed several mutations. The RLORF12 gene of strain L-MSp75C contained a single T deletion at nucleotide position 67 and of 814 vaccine strain a large fragment deletion from nucleotide position 18 to 86, both of the deletions located in Origin of replication site (Ori) of MDV genome. But strain L-ZYp75C possessed an unique "TGTTGGG" deletion in its RLORF12 gene. When the four Chinese epidemic MDV strains were serially passaged on CEF, the number of copies of the 132bp repeats increased from 2 to more than 10 copies. All of above results indicated that deletion and/or insertion mutation occurred in Meq, RLORF4, RLORF12 and 132bpr after serial passage of these four Chinese epidemic MDV strains on CEF.
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Doença de Marek/virologia , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Células Cultivadas , Embrião de Galinha , Galinhas , Análise Mutacional de DNA , Fibroblastos , Doença de Marek/genética , Dados de Sequência Molecular , Mutação , Fases de Leitura Aberta/genética , Homologia de Sequência de Aminoácidos , Proteínas Virais/químicaRESUMO
To investigate the occupational exposure levels to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs), indoor dust (n = 3) in workshops and hair samples from male workers (n = 64) were collected at two electrical and electronic equipmentwaste (E-waste) dismantling factories located in the LQ area in east China in July 11--13, 2006. Pre- and postworkshift urines (64 of each) were also collected from the workers to study oxidative damage to DNA using 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a biomarker. The concentrations of PCDD/Fs, PCDD/F-WHO-TEQs, PBDEs, PCBs and PCB-WHO-TEQs were (50.0 +/- 8.1) x 10(3), 724.1 +/- 249.6, (27.5 +/- 5.8) x 10(6), (1.6 +/- 0.4) x 10(9), (26.2 +/- 3.0) x 10(3) pg/g dry weight (dw) in dust, and (2.6 +/- 0.6) x 10(3),42.4 +/- 9.3, (870.8 +/- 205.4) x 10(3), (1.6 +/- 0.2) x 10(6), 41.5 +/- 5.5 pg/g dw in hair, respectively. The homologue and congener profiles in the samples demonstrated that high concentrations of PCDD/Fs, PBDEs, and PCBs were originated from open burning of E-waste. The 8-OHdG levels were detected at 6.40 +/- 1.64 micromol/mol creatinine in preworkshift urines. However, the levels significantly increased to 24.55 +/- 5.96 micromol/mol creatinine in postworkshift urines (p < 0.05). Then, it is concluded that there is a high cancer risk originated from oxidative stress indicated by the elevated 8-OHdG levels in the E-waste dismantling workers exposed to high concentrations of PCDD/Fs, PBDEs, and PCBs.
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Poluentes Ocupacionais do Ar/análise , Desoxiguanosina/análogos & derivados , Eletrônica , Exposição Ocupacional/análise , Éteres Fenílicos/análise , Bifenil Polibromatos/análise , Bifenilos Policlorados/análise , Dibenzodioxinas Policloradas/análogos & derivados , 8-Hidroxi-2'-Desoxiguanosina , Adolescente , Adulto , Desoxiguanosina/urina , Poeira/análise , Monitoramento Ambiental , Cabelo/química , Humanos , Masculino , Pessoa de Meia-Idade , Dibenzodioxinas Policloradas/análise , Gerenciamento de ResíduosRESUMO
OBJECTIVE: To study the interaction between polymorphisms of estrogen receptor (ER) gene and puberty on bone mineral density (BMD). METHODS: One hundred and forty-six boys aged 13-17 years were divided into two groups according to their first spermorrhea. DNA was analyzed for Xba I and Pvu II genotypes by PCR-RFLP. BMD of the total body, forearm and lumbar spine was measured by dual-energy X-ray absorptiometry (DXA). The relationship between polymorphisms of ER gene and BMD in these two groups was analyzed. RESULTS: The BMD at all sites in the spermorrhea group was significantly higher than that in the un-spermorrhea group. The independent contribution of ER genotypes to BMD at two pubertal stages was analyzed after adjusting co-variables. In the un-spermorrhea group, the BMD at distal 1/10 and 1/3 forearm of those carrying pp genotype was significantly higher than that of the non-carries, whereas in the spermorrhea group BMD in those carrying the same genotype was significantly lower than that in the non-carriers. Similar results were obtained by haplotype analysis. Multiple stepwise regression analysis showed that body weight, age and the first spermorrehea were the dominant determinants for BMD. BMD at forearm might be influenced by interaction between ER genotype and the first spermorrehea. CONCLUSION: The polymorphisms of ER gene play a different role in BMD influenced by the first spermorrhea. Chinese boys carrying p or x allele should pay more attention to their bone mass.