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1.
Sheng Li Xue Bao ; 74(3): 370-380, 2022 Jun 25.
Artigo em Zh | MEDLINE | ID: mdl-35770635

RESUMO

Polycystic ovary syndrome (PCOS) is a common disease caused by complex endocrine and metabolic abnormalities in women of childbearing age. Metformin is the most widely used oral hypoglycemic drug in clinic. In recent years, metformin has been used in the treatment of PCOS, but its mechanism is not clear. In this study, we aimed to investigate the effect of metformin on PCOS and its mechanism through PCOS mouse model. Female C57BL/6J mice aged 4-5 weeks were intragastrically given letrozole (1 mg/kg daily) combined with a high-fat diet (HFD) for 21 days to establish the PCOS model. After modeling, metformin (200 mg/kg daily) was intragastrically administered. One month later, the body weight and oral glucose tolerance test (OGTT) were measured. Hematoxylin eosin (H&E) staining was used to detect the pathological changes of ovary. The serum levels of anti-Mullerian hormone (AMH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), E2 and testosterone (T) were measured by ELISA. The expression of DDX4/MVH was detected by immunohistochemistry. DDX4/MVH and PCNA were co-labeled by immunofluorescence. The protein levels of DDX4/MVH, PCNA, cyclin D2, AMPK and mTOR were detected by Western blot. The results showed that after metformin treatment, the body weights of PCOS mice were gradually returned to normal, glucose tolerance was significantly improved, serum E2 levels were increased, while AMH, LH, T levels and LH/FSH ratio were decreased. Ovarian polycystic lesions were reduced with reduced atresia follicles. Furthermore, the number of proliferative female germline stem cells (FGSCs) and levels of proliferation related proteins (PCNA, cyclin D2) were significantly increased, and the p-mTOR and p-AMPK levels were markedly up-regulated. These results suggest that metformin treatment not only improves hyperandrogenemia, glucose intolerance and polycystic ovarian lesions in PCOS, but also activates the function of FGSCs. The underlying mechanism may be related to the phosphorylation of AMPK and mTOR. These findings provide new evidence to use metformin in the treatment of PCOS and follicular development disorder.


Assuntos
Metformina , Células-Tronco de Oogônios , Cistos Ovarianos , Neoplasias Ovarianas , Síndrome do Ovário Policístico , Proteínas Quinases Ativadas por AMP , Animais , Ciclina D2 , Feminino , Hormônio Foliculoestimulante/uso terapêutico , Humanos , Hormônio Luteinizante/uso terapêutico , Metformina/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco de Oogônios/metabolismo , Cistos Ovarianos/tratamento farmacológico , Síndrome do Ovário Policístico/tratamento farmacológico , Antígeno Nuclear de Célula em Proliferação/uso terapêutico , Serina-Treonina Quinases TOR
2.
J Biochem Mol Toxicol ; 33(8): e22346, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31291034

RESUMO

Non-small-cell lung cancer (NSCLC) is one of the most prevalent type of lung cancers with an increased mortality rate in both developed and developing countries worldwide. Dieckol is one such polyphenolic drug extracted from brown algae which has proven antioxidant and anti-inflammatory properties. In the present study, we evaluated the anticancer property of dieckol against NSCLC cell line A549. The LC50 value of dieckol was found to be 25 µg/mL by performing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the antiapoptotic property of dieckol was analyzed by dual staining technique with acridine orange/propidium iodide (AO/PI) stains. It was further confirmed with flow cytometry analysis with Annexin FITC and JC-1 staining and the anti-invasive property was assessed by Transwell assay. The molecular mechanism of dieckol anticancer activity was confirmed by estimating the levels of caspases and by estimating the signaling proteins of Pi3K/AKT/mTOR signaling pathway using the immunoblotting technique. Our data suggest that dieckol is potent anticancer agent, it effectively inhibits the invasive and migratory property A549 cells and it also induces apoptosis via inhibiting Pi3K/AKT/mTOR signaling, activating the tumor suppressor protein E-cadherin signifying that dieckol is potent natural anticancer drug to treat NSCLC.


Assuntos
Benzofuranos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Proliferação de Células/efeitos dos fármacos , Neoplasias Pulmonares/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/metabolismo
3.
Biomed Chromatogr ; 31(5)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27790730

RESUMO

Neopanaxadiol (NPD), the main panaxadiol constituent of Panax ginseng C. A. Meyer (Araliaceae), has been regarded as the active component for the treatment of Alzheimer's disease. However, few references are available about pharmacokinetic evaluation for NPD. Accordingly, a rapid and sensitive method for quantitative analysis of NPD in beagle dog plasma based on ultra-performance liquid chromatography quadrupole time-of-flight mass spectrometry was developed and validated. Analytes were extracted from plasma by liquid-liquid extraction and chromatographic separation was achieved on an Agilent Zorbax Stable Bond C18 column. Detection was performed in the positive ion mode using multiple reaction monitoring of the transitions both at m/z 461.4 → 425.4 for NPD and internal standard of panaxadiol. All validation parameters, such as lower limit of quantitation, linearity, specificity, precision, accuracy, extraction recovery, matrix effect and stability, were within acceptable ranges and the method was appropriate for multitude sample determination. After oral intake, NPD was slowly absorbed and eliminated from circulatory blood system and corresponding plasma exposure was low. Application of this quantitative method will yield the first pharmacokinetic profile after oral administration of NPD to beagle dog. The information obtained here will be useful to understand the pharmacological effects of NPD.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Ginsenosídeos/sangue , Ginsenosídeos/farmacocinética , Espectrometria de Massas/métodos , Administração Oral , Animais , Cães , Feminino , Ginsenosídeos/administração & dosagem , Masculino
4.
Biomed Environ Sci ; 28(8): 616-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26383600

RESUMO

In this study, we searched multiple databases for all relevant original articles (1996-2013). To investigate blood lead levels (BLL) and possible risk factors for lead exposure among children in China A total of 388 articles met our inclusion criteria. The overall geometric mean (GM) BLL was 71 µg/L, and the prevalence of elevated BLL (EBLL, defined as BLL ⋝ 100 µg/L) was 18.48% among children. The prevalence of EBLL remained significantly higher among boys. In children less than 6 years of age, there were significantly increasing trends in both BLL and prevalence of EBLL in an age-dependent manner. The ban on leaded gasoline significantly reduced the BLL as well as EBLL prevalence; however, children whose parents had lower educational levels or were exposed to lead in the workplace had a higher EBLL prevalence. Despite its decline over time, the average BLL among children in China remains higher than the average level most recently reported in the United States. Childhood lead poisoning remains a public health problem in China.


Assuntos
Chumbo/sangue , Criança , Pré-Escolar , China , Exposição Ambiental , Feminino , Humanos , Masculino , Fatores de Risco
5.
Cancer Cell Int ; 13(1): 90, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-24004462

RESUMO

BACKGROUND: Our recent evidence showed that Toll like receptor 9 (TLR9) signaling could enhance the growth and metastatic potential of human lung cancer cells through repressing microRNA-7 (miR-7) expression. Human antigen R (HuR) has been involved in stabilizing multiple mRNAs in cellular biology. However, whether HuR also contributed to the altered expression of miR-7 in TLR9 signaling stimulated human lung cancer cells remains to be elucidated. METHODS: The expression of HuR in human lung cancer 95D cells treated with TLR9 agonist CpG Oligonucleotides (ODNs) was detected by Real-time PCR and Western blot assay. To explore the possible role of HuR on miR-7 expression, eukaryotic expression vector encoding HuR was transiently transfected into 95D cells and then the expression of miR-7 was detected by Real-time PCR assay. Moreover, RNA interference, western blot, Real-time PCR, MTT assay, BrdU labeling, invasion assay and scratch assay were employed to examine the disrupt effect of HuR on miR-7 expression in human lung cancer cells treated with CpG ODNs. Finally, inhibitors for PI3K, Akt or Erk respectively, and western blot were performed to explore the possible signaling pathway related to HuR expression in CpG ODNs treated human lung cancer cells. RESULTS: Our data showed that TLR9 agonist CpG ODNs could induce the expression of HuR in human lung cancer cells. Moreover, overexpression of HuR could reduce the expression of miR-7 in lung cancer cells. Notably, down-regulation of HuR using RNA interference restored miR-7 expression in CpG ODNs treated lung cancer cells, accompanied by enhanced growth and metastatic potential. Finally, CpG ODNs could induce HuR expression through Akt pathway. CONCLUSION: Our findings indicated that HuR could act as regulator in regulating TLR9 signaling associated biological effect in human lung cancer cells, which might be helpful for the understanding of the potential role of HuR in tumor biology.

6.
J Huazhong Univ Sci Technolog Med Sci ; 33(1): 43-50, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23392706

RESUMO

Benzene is an established leukotoxin and leukemogen in humans. We have previously reported that exposure of workers to benzene and to benzene metabolite hydroquinone in cultured cells induced DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to mediate the cellular response to DNA double strand break (DSB) caused by DNA-damaging metabolites. In this study, we used a new, small molecule, a selective inhibitor of DNA-PKcs, 2-(morpholin-4-yl)-benzo[h]chomen-4-one (NU7026), as a probe to analyze the molecular events and pathways in hydroquinone-induced DNA DSB repair and apoptosis. Inhibition of DNA-PKcs by NU7026 markedly potentiated the apoptotic and growth inhibitory effects of hydroquinone in proerythroid leukemic K562 cells in a dose-dependent manner. Treatment with NU7026 did not alter the production of reactive oxygen species and oxidative stress by hydroquinone but repressed the protein level of DNA-PKcs and blocked the induction of the kinase mRNA and protein expression by hydroquinone. Moreover, hydroquinone increased the phosphorylation of Akt to activate Akt, whereas co-treatment with NU7026 prevented the activation of Akt by hydroquinone. Lastly, hydroquinone and NU7026 exhibited synergistic effects on promoting apoptosis by increasing the protein levels of pro-apoptotic proteins Bax and caspase-3 but decreasing the protein expression of anti-apoptotic protein Bcl-2. Taken together, the findings reveal a central role of DNA-PKcs in hydroquinone-induced hematotoxicity in which it coordinates DNA DSB repair, cell cycle progression, and apoptosis to regulate the response to hydroquinone-induced DNA damage.


Assuntos
Apoptose/fisiologia , Benzeno/toxicidade , Cromonas/farmacologia , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/fisiologia , Proteína Quinase Ativada por DNA/metabolismo , Morfolinas/farmacologia , Apoptose/efeitos dos fármacos , Catálise , Dano ao DNA/genética , Reparo do DNA/efeitos dos fármacos , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Humanos , Células K562 , Subunidades Proteicas
7.
Clin Cosmet Investig Dermatol ; 16: 2517-2523, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37745274

RESUMO

Leprosy is a chronic infectious disease primarily affecting the skin and peripheral nerves and is caused by Mycobacterium leprae. Although effective control measures have significantly reduced its global incidence in recent years, its insidious onset and diverse skin manifestations pose considerable challenges to early diagnosis, particularly among young medical practitioners. This study reports a case of tuberculoid leprosy accompanied by a type I reaction (T1R) to leprosy, aiming to contribute to the broader understanding and management of the disease. The patient came from a leprosy-endemic region and had a family history of leprosy. They first presented with neuritis, characterised by numbness in the left upper limb, which is an early-stage symptom often overlooked. This case accentuates the importance of comprehensive examination techniques, including bacteriological and histological investigations, ultrasound and magnetic resonance imaging, to identify early nerve damage, which is critical for prompt diagnosis and intervention. According to World Health Organization data, approximately 200,000 new cases of leprosy are reported worldwide each year, with a prevalence rate of 0.2 cases per 10,000 individuals. The disease exhibits two clinical forms based on the host's immune response: tuberculoid leprosy in a well-immunised population and lepromatous leprosy in a poorly immunised host. The patient in this study demonstrated signs of tuberculoid leprosy, marked by isolated skin papules and plaques, and a T1R, a tissue-destructive, immune-driven inflammatory process. This case underscores the need for ongoing education and updated diagnostic tools to facilitate the early detection of leprosy, particularly in endemic areas. Moreover, attention must be given to the comprehensive care of patients, encompassing both physical and psychological aspects, to improve their quality of life and mitigate social discrimination and prejudice.

8.
RSC Adv ; 12(15): 9179-9185, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-35424873

RESUMO

Chitosan extracted from natural products has gained tremendous attention in the field of adsorption and separation due to its inherent biocompatibility and potential applications. In this research, we synthesized a new type of spherical chitosan adsorbent (SCA) by controlling the mass transfer rate of the entanglement of the polymer chains in the recombination process. This SCA is a highly crystalline polymer material with outstanding mechanical strength, high adsorption capacity, a porous surface and suitable particle size distribution. The value of the sphericity of attrition of this SCA was 89.8%, which is the same as that of the commercial macroporous resin with a polystyrene matrix. The X-ray diffraction (XRD) patterns and differential scanning calorimetry (DSC) curves showed a significant change from powder to spherical structure and confirmed that the SCA is highly ordered and crystalline. Optical microscopy (OM) and scanning electron microscopy (SEM) demonstrated that the SCA was composed of a tightly stacked fiber structure, indicating the homogeneity of the polymerization. The porous structure of the surface provided a channel for mass transfer, which was indicated by a test of the ion exchange capacity and the adsorption performance of the SCA with Cu(ii) as the adsorbed subject. The adsorption capacity was higher than those of all reported non-composite chitosan materials. Therefore, we have successfully synthesized a completely green, nontoxic and environmentally friendly adsorbing resin equipped with excellent mechanical properties and adsorption capacity for future applications in many new fields.

9.
J Neurosurg ; : 1-8, 2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36272122

RESUMO

OBJECTIVE: Neurofibromatosis type 2 (NF2) is a rare autosomal dominant syndrome associated primarily with bilateral vestibular schwannomas (VSs). Conventional surgical or radiosurgical treatments for VS in NF2 usually result in high risks of hearing loss and facial nerve impairment, while there is no validated medical option to date. This single-institution phase II study evaluated the efficacy and safety of icotinib, an oral epidermal growth factor receptor tyrosine kinase inhibitor, in patients with NF2 and progressive VS. METHODS: Icotinib was administered daily at 375 mg orally in a continuous 28-day course for up to 12 courses. The primary endpoint of the study was radiographic response assessed by brain MRI using 3D volumetric tumor analysis and defined as a ≥ 20% decrease in VS volume. Hearing function was evaluated as a secondary endpoint, with response defined as a statistically significant increase in word recognition scores. RESULTS: Ten eligible patients with a mean age of 23.8 years were enrolled. One patient (10%) with bilateral tumors experienced an objective radiographic response (-23.58% and -22.01%). Three (43%) of 7 patients met the hearing response criteria. At 12 months, the estimated progression-free survival was 82.0% (95% CI 42.3%-95.5%) for volumetric progression and 69.2% (95% CI 37.3%-87.2%) for hearing progression. Common mild to moderate adverse events included rash (90%), diarrhea (50%), myalgia (20%), and nausea/gastrointestinal pain (20%). CONCLUSIONS: Icotinib carries minor toxicity and is associated with radiographic and hearing responses in patients with NF2 and progressive VS.

10.
J Mater Sci Mater Med ; 22(4): 853-63, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21373811

RESUMO

Recently, many efforts have been devoted to investigating the application of functionalized micelles as targeted drug delivery carriers. In this study, glycyrrhetinic acid (GA, a liver targeting ligand) modified poly(ethylene glycol)-b-poly(γ-benzyl L-glutamate) micelles were prepared and evaluated as a potential liver-targeted drug carrier. The aggregation behavior, stability, size and morphology of the micelles were investigated. Anticancer drug doxorubicin (DOX) was encapsulated in the micelles. The drug release profile, in vivo distribution and the cytotoxicity against hepatic carcinoma QGY-7703 cells of DOX-loaded micelles were studied. The results indicated that the release profile was pH-dependent with Fickian diffusion kinetics. The micelles were remarkably targeted to the liver, inducing a 4.9-fold higher DOX concentration than that for free DOX · HCl. The DOX-loaded micelles exhibited almost twofold more potent cytotoxicity compared with DOX · HCl, and the cytotoxicity was time- and dosage-dependent. These results suggest that GA-functionalized micelles represent a promising carrier for drug delivery to the liver.


Assuntos
Portadores de Fármacos/química , Ácido Glicirretínico/química , Fígado/metabolismo , Micelas , Animais , Antineoplásicos/administração & dosagem , Biodegradação Ambiental , Sistemas de Liberação de Medicamentos , Hepatócitos/metabolismo , Ligantes , Modelos Químicos , Polietilenoglicóis/química , Ácido Poliglutâmico/análogos & derivados , Ácido Poliglutâmico/química , Polímeros/química , Ratos
11.
Biochem Biophys Res Commun ; 382(3): 571-6, 2009 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-19302975

RESUMO

Accumulating data suggested that CXCR4/SDF-1 pathway may play an important role in the metastasis of tumor. We previously demonstrated that CpG ODN could enhance the metastasis of human lung cancer cell via TLR9. Here we further evaluated the possible role of CXCR4/SDF-1 pathway in the enhanced metastasis of human lung cancer 95D cells induced by CpG ODN. Our data showed down-regulation of CXCR4 expression using siRNA against CXCR4 could significantly reduce the enhanced metastasis of 95D cells induced by CpG ODN both in vitro and in vivo. These results suggested that TLR9 agonist might promote the metastasis of human lung cancer cells via CXCR4/SDF-1 pathway.


Assuntos
Quimiocina CXCL12/metabolismo , Neoplasias Pulmonares/patologia , Oligodesoxirribonucleotídeos/farmacologia , Receptores CXCR4/metabolismo , Receptor Toll-Like 9/agonistas , Animais , Movimento Celular , Quimiocina CXCL12/genética , Regulação para Baixo , Humanos , Neoplasias Pulmonares/metabolismo , Camundongos , Camundongos Nus , Metástase Neoplásica , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno/genética , Receptores CXCR4/genética , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(6): 1478-81, 2009 Jun.
Artigo em Zh | MEDLINE | ID: mdl-19810512

RESUMO

As an image-spectrum merging technology, hyperspectral imaging has been used in battlefield reconnaissance rapidly. According to the definition of MTF based on contrast, the theoretical model of the MTF of line-array CCD was presented. The effect of the relative position of linearray CCD and input signal on MTF was analyzed. The results indicate that at the frequency-division of Nyquist frequency, the relative position has a strong effect on the MTF, which becomes much stronger with frequency increase, while at other frequency, the effect of the relative position on MTF depends on the percent error zeta, e.g. the bigger the value of [zeta], the weaker the effect of the relative position on MTF. In the frequency range of [zeta] > 0.1%, the effect of the relative position on MTF can be ignored. The above conclusions have directive significance in the design of MTF measure system of hyperspectral imager.

13.
Biol Trace Elem Res ; 123(1-3): 109-15, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18193172

RESUMO

We investigated the relationship between oxidative stress and osteoblasts viability in osteoblasts exposed to various concentrations of fluoride in this study. Primary calvarial osteoblasts from neonatal Kunming mice were cultured and subcultured to the third generation. Osteoblasts were incubated with sodium fluoride (0, 0.5, 1, 2, 4, 8, 12, and 20 mgF(-)/L) for 24, 48, and 72 h. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) analysis showed cell viability significantly increased after osteoblasts exposed to low concentrations of fluoride (0.5 to approximately 2 mgF(-)/L) for 24 to approximately 72 h. Oxidative stress analysis showed that low concentration of fluoride excited lipid peroxidation in osteoblasts and increased activity of antioxidant enzymes in varying degrees. We demonstrated that changes of osteoblasts viability of the low-dose fluoride groups are different from those of high-dose fluoride groups; however, both low and high doses of fluoride caused active state of oxidative stress in osteoblasts, which suggesting that oxidative stress may be excited by the active osteoblasts viability induced by a low dose of fluoride.


Assuntos
Osteoblastos/efeitos dos fármacos , Estresse Oxidativo , Fluoreto de Sódio/farmacologia , Animais , Animais Recém-Nascidos , Células Cultivadas , Ensaio de Imunoadsorção Enzimática , Camundongos , Osteoblastos/metabolismo
14.
Shanghai Kou Qiang Yi Xue ; 27(1): 61-64, 2018 Feb.
Artigo em Zh | MEDLINE | ID: mdl-29946644

RESUMO

PURPOSE: To compare the clinical efficacy of CAD/CAM all-ceramic inlay and polymerid porcelain inlay in restoring Class II cavity of posterior teeth. METHODS: Ninety-seven patients with 100 posterior teeth of ClassII cavity were recruited in this randomized control trial; Among them, 50 patients were grouped into CAD/CAM all-ceramic inlays and 47 patients were grouped into Ceramage polymerid porcelain inlay. According to the modified USPHS criteria, the incidence of postoperative sensitivity, prosthesis fracture, prosthesis falling off, and edge coloration were evaluated 12 months and 24 months after restoration. Chi-square test and Wilcoxon rank sum test were used for statistical analysis using SPSS 13.0 software package. RESULTS: Restoration in the 2 groups were successful, there was no significant difference at 12 months (P>0.05). Postoperative sensitivity and the incidence of prosthesis falling off in both groups were not significantly different (P>0.05); however, the number of prosthesis fracture of the polymerid porcelain was lower than that of the CAD/CAM all-ceramic inlays (P<0.05). The incidence of edge coloration of CAD/CAM all-ceramic inlays was lower than that of the polymerid porcelain at 24-month follow-up (P<0.05). CONCLUSIONS: Restoration with polymerid porcelain is more likely to have a higher success rate than those with CAD/CAM all-ceramic inlays. Patients undergoing CAD/CAM all-ceramic inlays have a lower incidence of edge coloration, compared with those undergoing polymerid porcelain.


Assuntos
Desenho Assistido por Computador , Porcelana Dentária , Reparação de Restauração Dentária , Restaurações Intracoronárias , Cerâmica , Humanos , Resultado do Tratamento
15.
Radiat Prot Dosimetry ; 174(3): 302-307, 2017 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27342453

RESUMO

Due to the improvement of production technology and the adjustment of energy structure, as well as the town-ownership and private-ownership coal mines (TPCM) were closed or merged by national policy, the number of underground miner has changed comparing with 2004 in China, so collective dose and normalization collective dose in different type of coal mine should be changed at the same time. In this paper, according to radiation exposure by different ventilation condition and the annual output, the coal mines in China are divided into three types, which are named as national key coal mines (NKCM), station-owned local coal mines (SLCM) and TPCM. The number of underground coal miner, collective dose and normalization collective dose are estimated at present base on surveying annual output and production efficiency of raw coal in 2005-2014. The typical total value of the underground coal miners recommended in China is 5.1 million in 2005-2009, and in which there are respectively included 1 million, 0.9 million and 3.2 million for NKCM, SLCM and TPCM. There are total of 4.7 million underground coal miner in 2010-2014, and the respectively number for NKCM, SLCM and TPCM are 1.4 million, 1.2 million and 2.1 million. The collective dose in 2005-2009 is 11 335 man·Sv·y-1, and in which there are respectively included 280, 495 and 10 560 man·Sv·y-1 for NKCM, SLCM and TPCM. As far as 2010-2014, there are total of 7982 man·Sv·y-1, and 392, 660 and 6930 man·Sv·y-1 for each type of coal mines. Therefore, the main contributor of collective dose is from TPCM. The normalization collective dose in 2005-2009 is 0.0025, 0.015 and 0.117 man·Sv per 10 kt for NKCM, SLCM and TPCM, respectively. As far as 2010-2014, there are 0.0018, 0.010 and 0.107 man·Sv per 10 kt for each type of coal mines. The trend of normalization collective dose is decreased year by year.


Assuntos
Minas de Carvão , Exposição à Radiação , China , Carvão Mineral , Humanos , Masculino , Ventilação
16.
Shanghai Kou Qiang Yi Xue ; 26(5): 545-548, 2017 Oct.
Artigo em Zh | MEDLINE | ID: mdl-29308519

RESUMO

PURPOSE: To evaluate the effect of age on the potential of dental pulp regeneration in young permanent teeth with periapical periodontitis. METHODS: A total of 30 mandibular premolars from 9-18 years old patients with pulp necrosis were divided into 2 groups, group A (younger age group): 9-13 years old, and group B (older age group): 14-18 years old. Revascularization procedures were performed for all patients. Follow-up was done for up to 18 months. Standardized radiographs of cone-beam CT (CBCT) were digitally evaluated for increase in root length and thickness. The data were analyzed by nonparametric two sample rank sum test using SPSS13.0 software package. RESULTS: After 18 months of follow-up, the clinical symptoms of the two groups disappeared. The cure rate of group A was significantly higher than that of group B (P=0.003). Radiographic analysis showed that the root length and root canal wall thickness in group A was significantly greater than those in group B (P<0.05). CONCLUSIONS: Root canal revascularization can be widely used in the treatment of dental pulp necrosis in young permanent teeth. The closer the age is to the eruption time, the higher the potential of dental pulp regeneration, and the more suitable for root canal revascularization.


Assuntos
Necrose da Polpa Dentária , Dentição Permanente , Tratamento do Canal Radicular , Ápice Dentário , Adolescente , Criança , Humanos , Periodontite Periapical , Materiais Restauradores do Canal Radicular
17.
Biomaterials ; 27(24): 4381-7, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16677708

RESUMO

Here we introduce a new method for preparing a protein-imprinted polymer with immobilized assistant recognition polymer chains as an additional element of monomer to create effective recognition sites. In this work the bovine serum albumin was used as template and the template protein was selectively assembled with immobilized assistant recognition polymer chains from their library, numerous limited length polymer chains with randomly distributed recognition sites and immobilizing sites. These assemblies of protein and immobilized assistant recognition polymer chains would be adsorbed by the macro porous adsorbent spheres and immobilized by cross-linking polymerization. After removing the template, binding sites that were complementary to the target protein in size, shape and position of recognition groups were exposed, and their confirmation was preserved by the cross-linked structure. The synthesized imprinted polymer was used to adsorb BSA from protein mixtures, and showed a high selectivity.


Assuntos
Materiais Biocompatíveis , Álcool de Polivinil , Proteínas , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/química , Álcool de Polivinil/síntese química , Álcool de Polivinil/química
18.
Wei Sheng Yan Jiu ; 35(6): 731-4, 2006 Nov.
Artigo em Zh | MEDLINE | ID: mdl-17290753

RESUMO

OBJECTIVE: To investigate the impacts of the combined administration of ascorbic acid and thiamine on certain biochemical and morphologic indexes of testes in mice exposed to lead. METHOD: s 75 male mice were divided into control groups, groups received with 0.2% lead acetate and groups treated by the same lead acetate dose in combination with ascorbic acid and thiamine (subdivided into:low, middle and high-dose) ad libitum with 15 mice in each. 5 mice in each group were sacrificed at 2, 4 and 6 weeks respectively, and then testes were separated from mice. To evaluate the lead toxicity in testis, the levels of TGFbeta1 and Caspase-3 were detected by immunohistochemistry, apoptotic cell was determined by terminal deoxynucleotidyl transferase (TdT) mediated dUTP nick end labeling (TUNEL); DNA damage of germ cells was assessed by single cell gel electrophoresis (SCGE or Comet assay). RESULTS: The levels of TGFbeta1 and Caspase-3, apoptotic index were significantly higher in groups given by lead than those in control groups( P < 0.05 ). After intervention of low and middle-dose vitamins, DNA damage and the number of apoptotic cell in testis were obviously lower than those of groups exposed to lead( P < 0.05 ) . Also, the impaired tissues were markedly ameliorated under light microscope. Groups administrated with vitamins at the highest dose, however, promoted testicular cell apoptosis via elevated expression of TGFP, and Caspase-3, percentage of tail cell and tail length were reduced significantly. CONCLUSION: Thiamine and ascorbic acid could antagonize the action of certain toxicity of testes in mice treated by lead acetate.


Assuntos
Ácido Ascórbico/farmacologia , Suplementos Nutricionais , Chumbo/toxicidade , Testículo/efeitos dos fármacos , Tiamina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/biossíntese , Dano ao DNA , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Masculino , Camundongos , Camundongos Endogâmicos , Distribuição Aleatória , Testículo/metabolismo , Testículo/patologia , Fator de Crescimento Transformador beta1/biossíntese
19.
Zhongguo Yi Liao Qi Xie Za Zhi ; 30(3): 170-2, 2006 May.
Artigo em Zh | MEDLINE | ID: mdl-16929771

RESUMO

In this paper, some familiar algorithms of edge detection in ultrasound B-scan images are analyzed and studied. The results show that Sobel, Prewitt and Laplacian operators are sensitive to noise, Hough transform adapts to the whole detection, while LoG algorithm's average is zero and it couldn't change the whole dynamic area. Accordingly LoG algorithm is preferable.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Reconhecimento Automatizado de Padrão/métodos , Ultrassonografia/métodos , Artefatos , Humanos
20.
Zootaxa ; 4158(3): 443-50, 2016 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-27615896

RESUMO

Two new species are described: Podalonia arcuaticlypeata Wang & Ma, sp. nov. from Xinjiang, China and Podalonia bicellularis Wang & Ma, sp. nov. from Qinghai, China. A key to the species of Podalonia from China is provided.


Assuntos
Himenópteros/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Tamanho Corporal , China , Feminino , Himenópteros/anatomia & histologia , Himenópteros/crescimento & desenvolvimento , Masculino , Tamanho do Órgão
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