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1.
Cell Death Dis ; 12(11): 1082, 2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34775482

RESUMO

Expounding the heterogeneity for ovarian cancer (OC) with the cognition in developmental biology might be helpful to search for robust prognostic markers and effective treatments. In the present study, we employed single-cell RNA-seq with ovarian cancers, normal ovary, and embryo tissue to explore their heterogeneity. Then the differentiation process of clusters was explored; the pivotal cluster and markers were identified. Furthermore, the consensus clustering algorithm was used to explore the different clinical phenotypes in OC. At last, a prognostic model was construct and used to assess the prognosis for OCs. As a result, eight diverse clusters were identified, and the similarity existed in some clusters between embryo and tumours based on their gene expression. Meaningfully, a subtype of malignant epithelial cluster, PEG10+ EME, was associated with poor survival and was an intermediate stage of embryo to tumour. PEG10 was a CSC marker and might influence CSC self-renewal and promote cisplatin resistance via NOTCH pathway. Utilising specific gene profiles of PEG10+ EME based on public data sets, four phenotypes with different survival and clinical response to anti-PD-1/PD-L1 immunotherapy were identified. These insights allowed for the investigation of single-cell transcriptome of OCs and embryo, which advanced our current understanding of OC pathogenesis and resulted in promising therapeutic strategies.

3.
BMC Pregnancy Childbirth ; 21(1): 568, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34407784

RESUMO

BACKGROUNDS: Pregnancy termination during the second trimester in patients with placenta previa and placenta accreta spectrum (PAS) is a complex and challenging clinical problem. Based on our literature review, there has been a relative increase in the number of such cases being treated by hysterotomy and/or local uterine lesion resection and repair. In the present study, a retrospective analysis was conducted to compare the clinical outcomes when different management strategies were used to terminate pregnancy in the patients with placenta previa and PAS. METHODS: A total of 51 patients who underwent pregnancy termination in the second trimester in Beijing Obstetrics and Gynecology Hospital between June 2013 and December 2018 were retrospectively analyzed in this study. All patients having previous caesarean delivery (CD) were diagnosed with placenta previa status and PAS. RESULTS: ① Among the 51 patients, 16 cases received mifepristone and misoprostol medical termination, 15 cases received mifepristone and Rivanol medical termination, but 1 of them was transferred to hysterotomy due to failed labor induction, another 20 cases were performed planned hysterotomy. There was no placenta percreta cases and uterine artery embolization (UAE) was all performed before surgery.② There were 31 cases who underwent medical termination and 30 cases were vaginal delivery. Dilation and evacuation (D&E) were used in 20 cases of medical abortion failure and in all 30 cases of difficult manual removal of placental tissue. ③ A statistically significant difference was found among the three different strategies in terms of gestational weeks, the type of placenta previa status, main operative success rate and ß-HCG regression time (P < 0.05). ④ There were 4(7.8%) cases who were taken up for hysterectomy because of life-threatening bleeding or severe bacteremia during or after delivery and hysterotomy. The uterus was preserved with the implanted placenta partly or completely left in situ in 47(92.2%) cases. Combined medical and/or surgical management were used for the residual placenta and the time of menstrual recovery was 52(range: 33 to 86) days after pregnancy termination. CONCLUSIONS: Terminating a pregnancy by vaginal delivery through medical induction of labor may be feasible if clinicians have an overall understanding of gestational age, the type of placenta previa status, the type of placenta accreta, and patients concerns about preserving fertility. A collaborative team effort in tertiary medical centers with a very experience MDT and combined application of multiple methods is required to optimize patient outcomes.

4.
Mol Cancer ; 20(1): 98, 2021 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-34325714

RESUMO

BACKGROUND: Breast cancer (BC) has a marked tendency to spread to the bone, resulting in significant skeletal complications and mortality. Recently, circular RNAs (circRNAs) have been reported to contribute to cancer initiation and progression. However, the function and mechanism of circRNAs in BC bone metastasis (BC-BM) remain largely unknown. METHODS: Bone-metastatic circRNAs were screened using circRNAs deep sequencing and validated using in situ hybridization in BC tissues with or without bone metastasis. The role of circIKBKB in inducing bone pre-metastatic niche formation and bone metastasis was determined using osteoclastogenesis, immunofluorescence and bone resorption pit assays. The mechanism underlying circIKBKB-mediated activation of NF-κB/bone remodeling factors signaling and EIF4A3-induced circIKBKB were investigated using RNA pull-down, luciferase reporter, chromatin isolation by RNA purification and enzyme-linked immunosorbent assays. RESULTS: We identified that a novel circRNA, circIKBKB, was upregulated significantly in bone-metastatic BC tissues. Overexpressing circIKBKB enhanced the capability of BC cells to induce formation of bone pre-metastatic niche dramatically by promoting osteoclastogenesis in vivo and in vitro. Mechanically, circIKBKB activated NF-κB pathway via promoting IKKß-mediated IκBα phosphorylation, inhibiting IκBα feedback loop and facilitating NF-κB to the promoters of multiple bone remodeling factors. Moreover, EIF4A3, acted acting as a pre-mRNA splicing factor, promoted cyclization of circIKBKB by directly binding to the circIKBKB flanking region. Importantly, treatment with inhibitor eIF4A3-IN-2 reduced circIKBKB expression and inhibited breast cancer bone metastasis effectively. CONCLUSION: We revealed a plausible mechanism for circIKBKB-mediated NF-κB hyperactivation in bone-metastatic BC, which might represent a potential strategy to treat breast cancer bone metastasis.

6.
J Am Heart Assoc ; 9(12): e015513, 2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32476536

RESUMO

Background Aberrant activation of the NLRP3 (nucleotide-binding oligomerization domain, leucine-rich repeat-containing receptor family pyrin domain-containing 3) inflammasome is thought to play a causative role in atherosclerosis. NLRP3 is kept in an inactive ubiquitinated state to avoid unwanted NLRP3 inflammasome activation. This study aimed to test the hypothesis that pharmacologic manipulating of NLRP3 ubiquitination blunts the assembly and activation of the NLRP3 inflammasome and protects against vascular inflammation and atherosclerosis. Since genetic studies yielded mixed results about the role for this inflammasome in atherosclerosis in low-density lipoprotein receptor- or apolipoprotein E-deficient mice, this study attempted to clarify the discrepancy with the pharmacologic approach using both models. Methods and Results We provided the first evidence demonstrating that tranilast facilitates NLRP3 ubiquitination. We showed that tranilast restricted NLRP3 oligomerization and inhibited NLRP3 inflammasome assembly. Tranilast markedly suppressed NLRP3 inflammasome activation in low-density lipoprotein receptor- and apolipoprotein E-deficient macrophages. Through reconstitution of the NLRP3 inflammasome in human embryonic kidney 293T cells, we found that tranilast directly limited NLRP3 inflammasome activation. By adopting different regimens for tranilast treatment of low-density lipoprotein receptor- and apolipoprotein E-deficient mice, we demonstrated that tranilast blunted the initiation and progression of atherosclerosis. Mice receiving tranilast displayed a significant reduction in atherosclerotic lesion size, concomitant with a pronounced decline in macrophage content and expression of inflammatory molecules in the plaques compared with the control group. Moreover, tranilast treatment of mice substantially hindered the expression and activation of the NLRP3 inflammasome in the atherosclerotic lesions. Conclusions Tranilast potently enhances NLRP3 ubiquitination, blunts the assembly and activation of the NLRP3 inflammasome, and ameliorates vascular inflammation and atherosclerosis in both low-density lipoprotein receptor- and apolipoprotein E-deficient mice.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Aterosclerose/prevenção & controle , Inflamassomos/metabolismo , Macrófagos/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Vasculite/prevenção & controle , ortoaminobenzoatos/farmacologia , Animais , Aterosclerose/metabolismo , Aterosclerose/patologia , Modelos Animais de Doenças , Células HEK293 , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Camundongos Knockout para ApoE , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Placa Aterosclerótica , Receptores de LDL/deficiência , Receptores de LDL/genética , Ubiquitinação , Vasculite/metabolismo , Vasculite/patologia
7.
J Fluoresc ; 30(4): 883-890, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32494936

RESUMO

Based on boron-dipyrromethene (BODIPY), taking 2-hydroxy-N-(2-hydroxyphenyl)benzamide as recognition site, a new fluorescent probe HHPBA-BODIPY aimed at sensitively detecting Cu ions was designed, synthesized and characterized.The emission spectra of HHPBA-BODIPY exhibited an intensive green fluorescence around 510 nm, with a maximum absorption near 500 nm. When Cu2+ ions are present, the fluorescence at 510 nm can be quenched with a good linearity between the copper ion concentrationand the fluorescence intensity and the detection limit is 0.35 µM. HHPBA-BODIPY is also selective toward Cu2+, while other metal ions show no interfere except Fe3+ and Cr3+ ions. In addition, HHPBA-BODIPY also proved efficient to detect Cu2+ in water samples which offers the possibility to detect trace amount of Cu2+ for environmental monitoring. Copper ions; BODIPY; fluorescent probe.

8.
Mod Pathol ; 33(10): 1979-1988, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32404958

RESUMO

Hydatidiform moles are classified at the genetic level as androgenetic complete mole and diandric-monogynic partial mole. Conflicting data exist whether heterozygous complete moles are more aggressive clinically than homozygous complete moles. We investigated clinical outcome in a large cohort of hydatidiform moles in Chinese patients with an emphasis on genotypical correlation with post-molar gestational trophoblastic disease. Consecutive products of conceptions undergoing DNA genotyping and p57 immunohistochemistry to rule out molar gestations were included from a 5-year period at Beijing Obstetrics and Gynecology Hospital. Patient demographics and clinical follow-up information were obtained. Post-molar gestational trophoblastic disease or gestational trophoblastic neoplasia was determined by the 2002 WHO/FIGO criteria. A total of 1245 products of conceptions were classified based on genotyping results into 219 complete moles, 250 partial moles, and 776 non-molar gestations. Among 219 complete moles, 186 were homozygous/monospermic and 33 were heterozygous/dispermic. Among 250 partial moles, 246 were triploid dispermic, 2 were triploid monospermic, and 2 were tetraploid heterozygous partial moles. Among 776 non-molar gestations, 644 were diploid without chromosomal aneuploidies detectable by STR genotyping and 132 had various genetic abnormalities including 122 cases of various trisomies, 2 triploid digynic-monoandric non-molar gestations, 7 cases of possible chromosomal monosomy or uniparental disomy. Successful follow-up was achieved in 165 complete moles: post-molar gestational trophoblastic disease developed in 11.6% (16/138 cases) of homozygous complete moles and 37.0% (10/27 cases) of heterozygous complete moles. The difference between the two groups was highly significant (p = 0.0009, chi-square). None of the 218 partial moles and 367 non-molar gestations developed post-molar gestational trophoblastic disease. In conclusion, heterozygous/dispermic complete moles are clinically more aggressive with a significantly higher risk for development of post-molar gestational trophoblastic disease compared with homozygous/monospermic complete moles. Therefore, precise genotyping classification of complete moles is important for clinical prognosis and patient management.


Assuntos
Mola Hidatiforme Invasiva/genética , Mola Hidatiforme Invasiva/patologia , Neoplasias Uterinas/genética , Neoplasias Uterinas/patologia , Adulto , Feminino , Genótipo , Humanos , Mola Hidatiforme/genética , Mola Hidatiforme/patologia , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
9.
J Ovarian Res ; 12(1): 46, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113493

RESUMO

PURPOSE: To study the quality of our human ovarian tissue cryopreservation technique as performed in the first official "International Fertility Protection Centre" in China in patients with certain cancer types using a mouse model, and to find the best site for tissue transplantation in the mouse. METHODS: Thirty-six BALB/C female nude mice were randomly divided into 3 groups, group 1: control group; group 2: ovariectomized group; group 3: ovarian tissue transplantation group. Seventy-two pieces obtained from six ovarian tissue samples from each of three cancer patients were transplanted into the ovarian bursa cavity (OBC), the subcutaneous thigh (TS) and the subcutaneous neck (NS) and removed after 1.5 and 2.5 months, respectively. Follicular growth rate (FGR), total follicle surviving rate (TFSR), tissue recovery rate (TRR), antral follicles (AF), follicle stimulating hormone (FSH), estradiol (E2) and anti-Mullerian hormone (AMH) levels were measured. RESULTS: No significant differences in FGR, OBC, NS (p > 0.05); TFSR was 100% in OBC, NS and TS. No significant differences in TRR (p > 0.05); AF were found only in OBC; TFSR was 100% after transplantation; significantly higher FGR in the 2.5 months compared to the 1.5 months-group (p < 0.05). AMH- and E2-level in group 1 and 3 were significantly higher than in group 2 (p < 0.05); in contrast, FSH was significantly lower. CONCLUSIONS: After transplantation in the mice, the thawed ovarian tissue survived and follicles developed. The ovarian fossa site was the best site for transplantation. Our animal experiments can verify that our human ovarian tissue cryopreservation technique can preserve the quality of ovarian tissue. This is the essential precondition for successful re-transplantation into the patients after performing chemo/radiotherapy to protect ovarian function and fertility.


Assuntos
Criopreservação , Xenoenxertos/fisiologia , Folículo Ovariano/fisiologia , Folículo Ovariano/transplante , Ovário , Adulto , Animais , Hormônio Antimülleriano/metabolismo , Estradiol/metabolismo , Feminino , Preservação da Fertilidade , Hormônio Foliculoestimulante/metabolismo , Sobrevivência de Enxerto , Xenoenxertos/crescimento & desenvolvimento , Xenoenxertos/metabolismo , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Folículo Ovariano/crescimento & desenvolvimento , Folículo Ovariano/metabolismo , Ovário/cirurgia , Técnicas de Cultura de Tecidos , Transplante Heterólogo , Neoplasias do Colo do Útero/cirurgia
10.
Microbiologyopen ; 8(8): e00802, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30734523

RESUMO

To understand the impacts of peanut worms Sipunculus nudus on the prokaryotic community composition in a tidal flat, an onsite investigation was conducted in Suixi in the Beibu Gulf (109.82E, 21.35N) in the burrow sediments, non-burrow sediments and the sediments without peanut worm disturbance (control). The16S rRNA gene Illumina MiSeq sequencing was used to investigate the microbial communities and their response to bioturbation by S. nudus in a sandy tidal flat. A total of 18 bacteria phyla were detected, and Proteobacteria and Cyanobacteria constituted the majority of the prokaryotic community in the samples. The distribution of the relative abundances of genera showed that approximately 6.99%-17% of the reads in the samples were classified into 25 known genera. Sulfate-reducing bacteria (Desulfococcus and Desulfosarcina) were the most abundant taxa, followed by Thermodesulfovibrionaceae LCP-6, indicating that sulfate reduction is the main process in the sandy tidal flat. The abundances of Desulfococcus, LCP-6 and Cyanobacterium in the non-burrow sediment were greater than in the burrow sediment, suggesting that the anoxic condition is more suitable for Desulfococcus and LCP-6 when the activity of S. nudus is absent. The biomass of Cyanobacterium was decreased by the feeding bioturbation of S. nudus. Meanwhile, the relative abundance of the Bacteroidetes Luteimonas in the burrow sediments was significantly greater than in the non-burrow sediment, and there was a strong relationship between S. nudus bioturbation and increased in oxygen contents and oxidation-reduction potentials in the burrow sediment. The abundances of Desulfococcus and LCP-6 were greater in the middle layer (20-30 cm) than in the top layer in the non-burrow sediment. However, the middle and bottom layers (20-30, 30-40 cm) had higher abundances of these genera than did the upper layers (0-10, 10-20 cm) in the burrow sediments. The abundances of the Fusobacteria Propionigenium and the Spirochaetes Spirochaeta were greater in the middle and bottom layers (20-30 cm, 30-40 cm) than in the top layers (0-10, 10-20 cm) in the burrow sediment, but this phenomenon was not found in the non-burrow sediment. This study demonstrates that bioturbation by S. nudus plays an important role in reshaping the bacterial community composition in intertidal regions.


Assuntos
Bactérias/classificação , Biota , Helmintos/crescimento & desenvolvimento , Poliquetos/crescimento & desenvolvimento , Microbiologia do Solo , Animais , Arachis/parasitologia , Bactérias/genética , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Genes de RNAr , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
11.
Gynecol Endocrinol ; 35(4): 337-341, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30430877

RESUMO

The aim of this study was to investigate early clinical features and risk factors for cesarean scar pregnancy (CSP). Study group of 206 CSP patients out of 6853 women with early pregnancies, diagnosed from 2014 to 2016 was compared with a randomly selected control group of 412 patients. Early clinical features for CSP were vaginal bleeding (OR: 9.65; 95% CI: 5.67-16.41), lower abdominal pain (OR: 3.8; 95% CI: 1.52-9.54) and increased white blood cells (OR: 1.30; 95% CI: 1.12-1.50). Important risk factors for CSP were artificial abortion within the last pregnancy (OR: 4.13; 95% CI: 2.23-7.66), 0 ∼ 1 year and 2 ∼ 3 year interval between present and last pregnancy (OR: 2.27; 95% CI: 1.11-4.67 and OR: 2.15; 95% CI: 1.15-4.03). Pregnancy problems are important issues within the scope of 'Gynecological Endocrinology'. Vaginal bleeding and lower abdominal pain, although unspecific, could be early clinical symptoms of CSP, especially if main risk factors exist such as abortion within the last pregnancy and short interval to the last pregnancy. Knowing this can help for prevention and early diagnosis CSP which can reduce life-threatening complications such as massive hemorrhage and can avoid hysterectomy. Consequence also must be to avoid unwanted pregnancies by using effective contraception, especially in risk patients.


Assuntos
Cesárea/efeitos adversos , Cicatriz/complicações , Gravidez Ectópica/etiologia , Adulto , China/epidemiologia , Feminino , Humanos , Modelos Logísticos , Gravidez , Gravidez Ectópica/epidemiologia , Estudos Retrospectivos , Fatores de Risco
12.
J Fluoresc ; 28(4): 933-941, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29938389

RESUMO

A new boron-dipyrromethene (BODIPY) fluorescent dye aimed at sensitively detecting hypochlorite anion (ClO-) has been designed, synthesized and characterized. The probe is comprised of a BODIPY fluorophore unit and a ClO- specific reactive group of amidoxime. The addition of hypochlorite results in a red-shift of absorption and emission spectra of the probe accompanied by a decrease of intensity and spectra changes (A500 and 1/I512) of the probe can achieve a good linearity to the concentration of ClO-. The fluorescence probe can react to ClO- rapidly (within 60 s) in a wide pH range (4-10) with high sensitivity (detection limit of 6.81 µM) and selectivity. The reaction mechanism has been proposed and confirmed by MS analysis, ClO- anion oxidizes amidoxime moiety to hydroxyl group and hydroxyl group is further oxidized to formyl group in the formation of a corresponding aldehyde compound. In addition, the probe has also been successfully applied to detect ClO- in tap water and river water samples by spiking a known amount of standard ClO-.

13.
Polymers (Basel) ; 10(9)2018 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-30960891

RESUMO

Polytetrafluoroethylene/Poly(methyl methacrylate) (PTFE/PMMA) composite was prepared by mixing PTFE into PMMA matrix which synthesized by the PMMA powder mixture and methyl methacrylate (MMA) liquid mixture. The effects of the filling mass ratio of PTFE and powder/liquid (P/L) ratio on the friction and wear properties of PTFE/PMMA composites against bearing steel were studied by a ball-on-disk tribometer. Fourier transform infrared (FTIR), field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDS) were used to characterize the synthesis of PTFE/PMMA composite. The shore hardness and glass transition temperature (Tg) were obtained respectively by shore hardness tester and differential scanning calorimetry (DSC). The results show that the friction coefficient and wear rate of PMMA based composite, comparing with the unfilled PMMA, can be significantly reduced by filling with PTFE. With the increasing of PTFE filling mass ratio, the wear rate of PTFE/PMMA composite increases. The friction coefficient and wear rate of the unfilled PMMA and PTFE/PMMA composite generally decrease with the P/L ratio increasing. The main wear mechanism of the unfilled PMMA is adhesive wear. While the main wear mechanisms of PTFE/PMMA composites are fatigue wear and abrasive wear.

14.
Exp Ther Med ; 12(3): 1469-1475, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27602071

RESUMO

In the present study, we evaluated the diagnosis and management modalities of caesarean scar pregnancy (CSP). Thirty patients diagnosed with CSP were retrospectively studied between February, 2010 and February, 2012. Twenty-five patients were offered prophylactic uterine artery embolization (UAE) and methotrexate (MTX) prior to uterine suction curettage. Five cases were referred from other hospitals where the initial management with uterine suction curettage had resulted in uncontrollable massive haemorrhage, 4 of the cases had UAE and one proceeded immediately to hysterectomy. In the 25 patients treated with prophylactic UAE and MTX, 12 had laparoscopy-guided curettage and 13 had ultrasound-guided curettage without complication. The results showed that the 25 patients with CSP, who received prophylactic UAE and MTX prior to uterine curettage, recovered without complications. Five patients referred from other hospitals, where uterine curettage was the primary procedure, had severe complications including uncontrolled vaginal bleeding and uterine rupture. Four of the five patients were treated successfully with emergency UAE and the remaining patient underwent emergency hysterectomy as ultrasound examination detected significant haemorrhage between the uterus and the bladder. Of the 25 patients who received prophylactic UAE combined with MTX, there were no reports of irregular menstruation or serious adverse effects. Notably, the decrease in serum human chorionic gonadotropin (HCG) levels 3 days post-surgery was greater with ultrasound-guided curettage (84.3±5.5%) than with laparoscopy-guided curettage (76.3±10.2%). In summary, the data suggested that prophylactic UAE with MTX followed by ultrasound-guided curettage is the most effective therapeutic approach in CSP.

15.
Sci Total Environ ; 568: 1295-1307, 2016 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26879415

RESUMO

Maglev, offers competitive journey-times compared to the railway and subway systems in markets for which distance between the stations is 100-1600km owing to its high acceleration and speed; however, such systems may have excessive vibration. Field measurements of Maglev train-induced vibrations were therefore performed on the world's first commercial Maglev line in Shanghai, China. Seven test sections along the line were selected according to the operating conditions, covering speeds from 150 to 430km/h. Acceleration responses of bridge pier and nearby ground were measured in three directions and analyzed in both the time and frequency domain. The effects of Maglev train speed on vibrations of the bridge pier and ground were studied in terms of their peak accelerations. Attenuation of ground vibration was investigated up to 30m from the track centerline. Effects of guideway configuration were also analyzed based on the measurements through two different test sections with same train speed of 300km/h. The results showed that peak accelerations exhibited a strong correlation with both train speed and distance off the track. Guideway configuration had a significant effect on transverse vibration, but a weak impact on vertical and longitudinal vibrations of both bridge pier and ground. Statistics indicated that, contrary to the commonly accepted theory and experience, vertical vibration is not always dominant: transverse and longitudinal vibrations should also be considered, particularly near turns in the track. Moreover, measurements of ground vibration induced by traditional high-speed railway train were carried out with the same testing devices in Bengbu in the Anhui Province. Results showed that the Maglev train generates significantly different vibration signatures as compared to the traditional high-speed train. The results obtained from this paper can provide good insights on the impact of Maglev system on the urban environment and the quality of human life nearby.

16.
Dalton Trans ; 43(9): 3739-49, 2014 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-24435450

RESUMO

Three different functional SBA-15 were prepared by a post-grafting method using three iminodiacetic acid derivatives of ethylenediaminetriacetic acid (ED3A), diethylenetriaminetetraacetic acid (DT4A), and 1,2-cyclohexylenedinitrilotriacetic acid (CyD3A), which were used as adsorbents for removal of uranium(vi) from aqueous solution. These materials were characterized by FT-IR, NMR, TEM, nitrogen adsorption/desorption experiments, and elemental analysis. The effect of pH, ionic strength, contact time, solid-liquid ratio, initial metal ion concentration, temperature, and coexisting ions on uranium(vi) sorption behaviors of the functionalized SBA-15 was studied. Typical sorption isotherms (Langmuir and Freundlich) were determined for the sorption process, and the maximum sorption capacity was calculated. The influence of functional groups on uranium(vi) sorption was also discussed. As a result, compared with other current U(vi) sorbents (granite, kaolin, attapulgite), SBA-15-1,2-cyclohexylenedinitrilotriacetic acid (SBA-15-CyD3A) possessed good selective sorption properties, which had potential application in separation of uranium(vi).

17.
Ying Yong Sheng Tai Xue Bao ; 20(1): 223-7, 2009 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-19449590

RESUMO

A 4-factorial (water temperature, salinity, nitrogen, and phosphorus) experiment was designed to study the niche characteristics of four common microalgae communities in prawn-aquaculture pond. The results showed that the niche breadth was the greatest for Cryptomonas erosa in temperature and salinity resources (0.980 and 0.988, respectively) and for Niztzschia closterium in nitrogen and phosphorus resources (0.990), but the smallest for Chlorella pyrenoidosa in all test resources, with an average value of 0.926. As for niche overlap, it was the smallest for C. erosa and C. pyrenoidosa in temperature and salinity resources (0.809 and 0.702, respectively) and for C. erosa and N. closterium in nitrogen and phosphorus resources (0.829), but the greatest for C. pyrenoidosa and Nannichloropsis oculata in temperature, salinity, and nitrogen and phosphorus resources, with the values being 0.986, 0.974 and 0.989, respectively. All of these suggested that in prawn-aquaculture pond, C. erosa could be bred with any other three of the microalgae communities, while N. oculata and C. pyrenoidosa should not be bred together for their obvious competition


Assuntos
Aquicultura , Ecossistema , Eucariotos/classificação , Penaeidae/crescimento & desenvolvimento , Água/análise , Animais , Eucariotos/crescimento & desenvolvimento , Nitrogênio/análise , Fósforo/análise , Salinidade , Temperatura , Poluentes da Água/análise
18.
Artigo em Inglês | MEDLINE | ID: mdl-17329159

RESUMO

A new amide-based 1,3,4-oxadiazole derivative ligand 2,5-bis[2-(N,N-diethyl-1'-oxopropylamide)phenyl]-1,3,4-oxadiazole (L) and its complexes, Ln(NO3)3L (Ln=La, Eu, Gd, Tb, Er), were synthesized. The complexes were characterized by elemental analysis, infrared spectra and conductivity. The lanthanide ions were coordinated by O atoms from CO. The fluorescence properties of Eu(NO3)3L and Tb(NO3)3L in the solid state and in different solvents were investigated. Under the excitation of UV light, these complexes exhibit characteristic fluorescence of europium and terbium ions. The solvent factors influencing the fluorescent intensity were discussed.


Assuntos
Elementos da Série dos Lantanídeos/química , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Oxidiazóis/química , Oxidiazóis/síntese química , Ligantes , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Estrutura Molecular , Espectrometria de Fluorescência , Espectrofotometria , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Gastroenterology ; 130(6): 1625-35, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16697726

RESUMO

BACKGROUND & AIMS: Genotypes and viremia of hepatitis D virus (HDV) and hepatitis B virus (HBV) may be associated with outcomes. This study evaluated the impact of viral genotypes and viremia on outcomes of dual HBV and HDV infection. METHODS: Viremia and viral genotypes were analyzed in 194 consecutive chronic hepatitis B patients with HDV superinfection and correlated with outcomes. RESULTS: The numbers of HBV genotype A, B, C, and nonclassified were 4, 57, 23, and 110, respectively. There were 51 genotype I HDV, 74 genotype II HDV, 8 genotype IV HDV, and 61 nonclassified HDV genotype. In a median follow-up of 135 months, 24 progressed to cirrhosis and 41 developed hepatocellular carcinoma. Patients infected with genotype I HDV had a lower remission rate (15.2% vs 40.2%; P = .007) and more adverse outcomes (cirrhosis, hepatocellular carcinoma, or mortality) (52.2% vs 25.0%; P= .005) than those with genotype II HDV. Patients infected with genotype C HBV had a lower remission rate (0 vs 32.1%; P = .005) and more adverse outcomes (70.0% vs 33.9%; P = .005) than those with genotype B HBV. The presence of HBV or HDV viremia was associated with lower remission rates compared with those negative for both (26.4% and 24.3% vs 69.2%; P < .001). In multivariate analysis, age, genotype C HBV, and genotype I HDV were independent factors associated with adverse outcomes. CONCLUSIONS: In chronic HBV and HDV dual infections, older age, genotype I HDV, and genotype C HBV correlated with adverse outcomes.


Assuntos
DNA Viral/genética , Predisposição Genética para Doença , Hepatite B Crônica/genética , Hepatite D Crônica/genética , Viremia/genética , Adulto , Análise de Variância , Estudos de Coortes , Progressão da Doença , Feminino , Regulação da Expressão Gênica , Marcadores Genéticos , Genótipo , Hepatite B Crônica/epidemiologia , Hepatite B Crônica/fisiopatologia , Hepatite D Crônica/epidemiologia , Hepatite D Crônica/fisiopatologia , Humanos , Incidência , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Probabilidade , Prognóstico , Estudos Retrospectivos , Medição de Risco , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Taxa de Sobrevida , Taiwan/epidemiologia , Viremia/epidemiologia , Viremia/fisiopatologia
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 62(4-5): 826-30, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15953763

RESUMO

Four ligands 1,10-phenanthroline-5,6-bis(N,N-dibenzyl-1'-oxopropylamide) (La) 1,10-phenanthroline-5,6-bis(N-methyl-N-benzyl-1'-oxopropylamide) (Lb) 1,10-phenanthroline-5,6-bis(N-benzyl-1'-oxopropylamide) (Lc) and 1,10-phenanthroline-5,6-bis(N,N-diethyl-1'-oxopropylamide) (Ld), and their lanthanide(III) (La and Eu) complexes were synthesized. The complexes were characterized by elemental analysis, IR, fluorescence spectroscopy and conductivity. The lanthanide atoms are coordinated by O atoms from C=O, Ar-O -C and N atoms from phen With the difference of the ligands, the fluorescent intensities of the Eu(III) complexes vary regularly in the THF solution. Some factors that influence the fluorescent intensity were discussed.


Assuntos
Amidas/química , Európio/química , Nitratos/química , Fenantrolinas/química , Fenantrolinas/síntese química , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier
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