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1.
Sci Rep ; 12(1): 1366, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35079074

RESUMO

Numerous field examples of coal seam mining show that when coal seams under confined water are mined close to faults, water inrush effects on complex mining surfaces occur. Obeying similarity rules, physical similarity models consisting of sand, lime, and plaster were used to investigate the water conducting process, along with stress and displacement measured by a combination of mechanical senor, total station, and video camera-. Comparing the physical model tests with the calculation results of elastoplastic limit equilibrium theory, the rationality of the model has been verified. Besides, a safe width of the waterproof coal pillar has been obtained. It can be demonstrated from the model observations that the coal seam in front of the mining can be divided into three areas with different characteristics of stress and displacement, namely, which are the fault-affected area, the elastic area, and the plastic yield crack area. A closed-loop water inlet and outlet pipeline composed of a water control platform that can provide stable water pressure, and water bags pre-buried in the fault was used to simulate the water conduction in the fracture zone. Integrate the development law of stress, displacement, and water conduction coming from the upper and lower walls of the fault to further determine the reasonable width of the waterproof coal pillar.

2.
Artigo em Chinês | MEDLINE | ID: mdl-34624947

RESUMO

Objective: To understand the occupational health status of radiation workers at an international airport, and to provide basis and reference for relevant competent authorities to conduct scientific and effective occupational health monitoring. Methods: From July to August 2019, 246 radiation workers at an international airport were selected as the research subjects (observation group) , and their occupational health examination data were collected. At the same time, 210 radiation workers from a medical institution were selected as the control group. The occupational health examination results of the two groups were compared. And the differences in occupational health examination results of airport radiation workers among difference service age were analyzed. Results: Compared with the control group, the detection rates of ocular lens opacity (1.63%, 4/246) and abnormal blood glucose (4.07%, 10/246) in the observation group were lower, the detection rates of abnormal skin (11.79%, 29/246) , abnormal B-ultrasound of liver, gallbladder and spleen (75.61%, 186/246) and abnormal chest X-ray (5.28%, 13/246) were higher (P<0.05) . There were significant differences in the abnormal detection rates of skin, blood glucose, B-ultrasound of liver, gallbladder and spleen among airport radiation workers with different service age (P<0.05) . Abnormal chromosome of peripheral blood lymphocytes, abnormal chest X-ray were mainly distributed in the service age of ≥20 years. The abnormal rate of B-ultrasound of liver, gallbladder and spleen was higher in different working age groups. Conclusion: Long term low-dose irradiation will have a certain impact on the occupational health of airport radiation workers. The occupational health monitoring of relevant personnel should be strengthened to protect their occupational health.


Assuntos
Cristalino , Exposição Ocupacional , Saúde Ocupacional , Adulto , Aeroportos , Nível de Saúde , Humanos , Adulto Jovem
3.
Phys Rev Lett ; 125(19): 191801, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216576

RESUMO

We report a search result for a light sterile neutrino oscillation with roughly 2200 live days of data in the RENO experiment. The search is performed by electron antineutrino (ν[over ¯]_{e}) disappearance taking place between six 2.8 GW_{th} reactors and two identical detectors located at 294 m (near) and 1383 m (far) from the center of the reactor array. A spectral comparison between near and far detectors can explore reactor ν[over ¯]_{e} oscillations to a light sterile neutrino. An observed spectral difference is found to be consistent with that of the three-flavor oscillation model. This yields limits on sin^{2}2θ_{14} in the 10^{-4}≲|Δm_{41}^{2}|≲0.5 eV^{2} region, free from reactor ν[over ¯]_{e} flux and spectrum uncertainties. The RENO result provides the most stringent limits on sterile neutrino mixing at |Δm_{41}^{2}|≲0.002 eV^{2} using the ν[over ¯]_{e} disappearance channel.

4.
Phys Rev Lett ; 120(9): 097205, 2018 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-29547317

RESUMO

The key physics of the spin valve involves spin-polarized conduction electrons propagating between two magnetic layers such that the device conductance is controlled by the relative magnetization orientation of two magnetic layers. Here, we report the effect of a magnon valve which is made of two ferromagnetic insulators (YIG) separated by a nonmagnetic spacer layer (Au). When a thermal gradient is applied perpendicular to the layers, the inverse spin Hall voltage output detected by a Pt bar placed on top of the magnon valve depends on the relative orientation of the magnetization of two YIG layers, indicating the magnon current induced by the spin Seebeck effect at one layer affects the magnon current in the other layer separated by Au. We interpret the magnon valve effect by the angular momentum conversion and propagation between magnons in two YIG layers and conduction electrons in the Au layer. The temperature dependence of the magnon valve ratio shows approximately a power law, supporting the above magnon-electron spin conversion mechanism. This work opens a new class of valve structures beyond the conventional spin valves.

5.
Animal ; 12(4): 675-683, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28793941

RESUMO

We estimated the heritabilities (h 2) and genetic and phenotypic correlations among individual and groups of fatty acids, as well as their correlations with six important carcass and meat-quality traits in Korean Hanwoo cattle. Meat samples were collected from the longissimus dorsi muscles of 1000 Hanwoo steers that were 30-month-old (progeny of 85 proven Hanwoo bulls) to determine intramuscular fatty acid profiles. Phenotypic data on carcass weight (CWT), eye muscle area (EMA), back fat thickness (BFT), marbling score (MS), Warner-Bratzler shear force (WBSF) and intramuscular fat content (IMF) were also investigated using this half-sib population. Variance and covari.ance components were estimated using restricted maximum likelihood procedures under univariate and pairwise bivariate animal models. Oleic acid (C18:1n-9) was the most abundant fatty acid, accounting for 50.69% of all investigated fatty acids, followed by palmitic (C16:0; 27.33%) and stearic acid (C18:0; 10.96%). The contents of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) were 41.64%, 56.24% and 2.10%, respectively, and the MUFA/SFA ratio, PUFA/SFA ratio, desaturation index (DI) and elongation index (EI) were 1.36, 0.05, 0.59 and 0.66, respectively. The h 2 estimates for individual fatty acids ranged from very low to high (0.03±0.14 to 0.63±0.14). The h 2 estimates for SFAs, MUFAs, PUFAs, DI and EI were 0.53±0.14, 0.49±0.14, 0.23±0.10, 0.51±0.13 and 0.53±0.13, respectively. The genetic and phenotypic correlations among individual fatty acids and fatty acid classes varied widely (-0.99 to 0.99). Notably, C18:1n-9 had favourable (negative) genetic correlations with two detrimental fatty acids, C14:0 (-0.76) and C16:0 (-0.92). Genetic correlations of individual and group fatty acids with CWT, EMA, BFT, MS, WBSF and IMF ranged from low to moderate (both positive and negative) with the exception of low-concentration PUFAs. Low or near-zero phenotypic correlations reflected potential non-genetic contributions. This study provides insights on genetic variability and correlations among intramuscular fatty acids as well as correlations between fatty acids and carcass and meat-quality traits, which could be used in Hanwoo breeding programmes to improve fatty acid compositions in meat.


Assuntos
Bovinos/genética , Ácidos Graxos/metabolismo , Genótipo , Carne/análise , Fenótipo , Animais , Bovinos/metabolismo , Masculino , Músculos Superficiais do Dorso/química
6.
J Anim Sci ; 95(8): 3359-3369, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28805895

RESUMO

We estimated heritability () and genetic and phenotypic correlations for carcass and meat quality traits of longissimus dorsi (LD) and semimembranosus (SM) muscles in 30-mo-old Hanwoo steers. Variance and covariance components were estimated using REML procedures under univariate and bivariate models. The mean carcass weight (CWT), eye muscle area (EMA), back fat thickness (BFT), and marbling score (MS) were 428.20 ± 46.30 kg, 87.38 ± 8.54 cm2, 13.00 ± 5.14 mm, and 5.21 ± 1.56, respectively. The mean CIE reflectance of meat lightness (L*), redness (a*), and yellowness (b*) were 40.01 ± 2.73, 22.37 ± 2.18, and 10.35 ± 1.46, respectively, in LD muscles and 36.33 ± 2.44, 22.91 ± 2.43, and 10.25 ± 1.65, respectively, in SM muscles. The mean Warner-Bratzler shear force (WBSF), intramuscular fat content (IMF), water-holding capacity (WHC), and protein and ash content in LD and SM muscles were 3.84 ± 0.96 and 6.52 ± 1.21 kg, 15.91 ± 4.39 and 5.10 ± 1.94%, 62.07 ± 3.38 and 71.61 ± 2.06%, 20.01 ± 1.39 and 21.34 ± 0.89%, and 0.80 ± 0.10 and 0.93 ± 0.07, respectively. The estimates of CWT, EMA, BFT, and MS were 0.51 ± 0.13, 0.45 ± 0.13, 0.29 ± 0.09, and 0.22 ± 0.08, respectively. The estimates were moderate for meat quality traits and were 0.37 ± 0.12, 0.40 ± 0.12, 0.33 ± 0.10, 0.33 ± 0.10, 0.30 ± 0.11, and 0.24 ± 0.09 for L*, WBSF, IMF, WHC, and protein and ash content, respectively, in LD muscle; estimates from SM muscle were comparatively low (0.08 ± 0.06 to 0.25 ± 0.09). Estimates of for a* and b* were also low (0.08 ± 0.06 to 0.13 ± 0.07). Carcass weight had a moderate, positive genetic correlation with EMA (0.60 ± 0.13) and a weak correlation with MS and BFT. The genetic correlations among the 3 colorimeter variants were strong and positive within and between muscles. Intramuscular fat content had moderate to strong and negative genetic correlations with WBSF (-0.49 ± 0.18), WHC (-0.99 ± 0.01), and protein (-0.93 ± 0.04) and ash content (-0.98 ± 0.06) in LD muscle, whereas the associations were less pronounced in SM muscle. In general, CWT and EMA had low genetic and phenotypic correlations with meat quality traits, which suggests that the traits are independent and have distinct genetic contributions in each muscle. Conversely, with few exceptions, meat quality traits had genetic and phenotypic correlations with MS and BFT. In conclusion, the estimated genetic parameters for carcass and meat quality traits could be used for genetic evaluation and breeding programs in Korean Hanwoo cattle populations.


Assuntos
Bovinos/genética , Músculo Esquelético/fisiologia , Carne Vermelha/normas , Animais , Bovinos/classificação , Bovinos/fisiologia , Músculos Isquiossurais/fisiologia , Masculino , Músculos Paraespinais/fisiologia , Fenótipo , Carne Vermelha/análise , Água/fisiologia
7.
Zhonghua Xin Xue Guan Bing Za Zhi ; 44(2): 121-7, 2016 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-26926504

RESUMO

OBJECTIVE: To observe the efficacy and safety of bivalirudin use in Chinese patients with coronary heart disease (CHD) during the peri-percutaneous coronary intervention(PCI) period. METHODS: A total of 3 271 patients who underwent PCI and received periprocedural bivalirudin treatment between July 2013 and October 2015 from 88 centers of China were involved in this study. The primary outcome was 30-day net adverse clinical events (NACE a composite of major adverse cardiac or cerebral events (MACE, all-cause death, reinfarction, urgent target vessel revascularization, or stroke) or bleeding), the secondary outcome was stent thrombosis at 30 days. RESULTS: The mean age of enrolled patients was (65.12±12.44) years old, 27.4%(889/3 244) of them were female. Percent of stable coronary disease (SCD), non-ST segment elevation acute coronary syndrome (NSTE-ACS) and ST elevation myocardial infarction (STEMI) was 5.0%(162/3 248), 44.6%(1 450/3 248) and 50.4%(1 636/3 248) respectively. Radial access was performed in 89.5% (2 879/3 271) patients, and 9.7% (316/3 271) and 34.1% (1 115/3 271) patients also received ticagrelor and tirofiban medication. 69.3% (2 266/3 271) patients received post-procedural bivalirudin infusion, in which 46.3% (1 050/2 266) was treated at PCI-does, with a median duration of 2.5(1.0, 4.0) h. During the 30-day follow-up, NACE occurred in 3.45% (103/2 988) patients, the incidence of MACE, death was 2.17% (65/2 994) and 1.03% (31/3 017), respectively and bleeding events were recorded in 1.37% (41/2 996) patients. Four cases (0.13%) of stent thrombosis (3 acute stent thrombosis) were recorded. CONCLUSION: Peri-PCI Bivalirudin use is safe and related with low bleeding risk in Chinese CHD patients.


Assuntos
Doença das Coronárias , Idoso , China , Feminino , Hemorragia , Heparina , Hirudinas , Humanos , Masculino , Fragmentos de Peptídeos , Intervenção Coronária Percutânea , Proteínas Recombinantes , Estudos Retrospectivos , Acidente Vascular Cerebral , Tirofibana , Tirosina/análogos & derivados
8.
Phys Rev Lett ; 113(12): 121301, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25279618

RESUMO

Bosonic superweakly interacting massive particles (super-WIMPs) are a candidate for warm dark matter. With the absorption of such a boson by a xenon atom, these dark matter candidates would deposit an energy equivalent to their rest mass in the detector. This is the first direct detection experiment exploring the vector super-WIMPs in the mass range between 40 and 120 keV. With the use of 165.9 day of data, no significant excess above background was observed in the fiducial mass of 41 kg. The present limit for the vector super-WIMPs excludes the possibility that such particles constitute all of dark matter. The absence of a signal also provides the most stringent direct constraint on the coupling constant of pseudoscalar super-WIMPs to electrons. The unprecedented sensitivity was achieved exploiting the low background at a level 10(-4) kg-1 keVee-1 day-1 in the detector.

9.
Asian-Australas J Anim Sci ; 26(6): 780-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25049850

RESUMO

The objective of this study was to investigate single nucleotide polymorphisms (SNPs) in the bovine nephroblastoma overexpressed (NOV) gene and to evaluate whether these polymorphisms affect carcass traits in the Korean cattle population. We resequenced to detect SNPs from 24 unrelated individuals and identified 19 SNPs within the full 8.4-kb gene, including the 1.5-kb promoter region. Of these 19 SNPs, four were selected for genotyping based on linkage disequilibrium (LD). We genotyped 429 steers to assess the associations of these four SNPs with carcass traits. Statistical analysis revealed that g.7801T>C and g.8379A>C polymorphisms in the NOV gene were associated with carcass weight (p = 0.012 and 0.008, respectively), and the g.2005A>G polymorphism was associated with the back fat thickness (BF) trait (p = 0.0001). One haplotype of the four SNPs (GGTA) was significantly associated with BF (p = 0.0005). Our findings suggest that polymorphisms in the NOV gene may be among the important genetic factors affecting carcass yield in beef cattle.

10.
Br J Dermatol ; 168(1): 112-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23020072

RESUMO

BACKGROUND: Allergic contact dermatitis (ACD) is a delayed type of T cell-mediated cutaneous inflammatory response, in which multiple cell types are involved. Dasatinib and LCB 03-0110 are small molecule multityrosine kinase inhibitors, and they share remarkably similar target kinases such as the c-Src family, Btk and Syk, which play key roles in the cell signalling of T cells and other inflammatory cells. OBJECTIVES: To test the anti-ACD activity of dasatinib and LCB 03-0110 and compare it with that of tacrolimus (FK506) and triamcinolone acetonide (a glucocorticoid), which are widely used for topical treatment of ACD, and to examine the two compounds for their capacity to induce skin atrophy, a side-effect. METHODS: ACD was induced on the ears of mice by repeated topical application of oxazolone. Each test compound was then topically applied on the ear. Ear swelling, epidermal thickness and levels of inflammatory cytokines were measured. The skin atrophy induced by the compounds was tested during prolonged application on the dorsal skin of hairless mice, followed by haematoxylin and eosin staining. RESULTS: Dasatinib and LCB 03-0110 suppressed the symptoms of ACD such as ear swelling, increase in epidermal thickness and synthesis of inflammatory cytokines (i.e. interleukin-1ß, tumour necrosis factor-α and interferon-γ) in a dose-dependent manner. The two compounds showed near-equal potency to tacrolimus; however, their potency was lower than that of triamcinolone acetonide. Prolonged treatment with the two compounds did not induce any skin atrophy, whereas use of steroidal agents induced severe atrophy. CONCLUSIONS: Dasatinib and LCB 03-0110 could be used as effective agents for the treatment of ACD without the adverse side-effect of skin atrophy.


Assuntos
Aminopiridinas/administração & dosagem , Anti-Inflamatórios/administração & dosagem , Dermatite Alérgica de Contato/prevenção & controle , Inibidores de Proteínas Quinases/administração & dosagem , Pirimidinas/administração & dosagem , Pele/patologia , Tiazóis/administração & dosagem , Tiofenos/administração & dosagem , Adjuvantes Imunológicos , Administração Cutânea , Animais , Atrofia/tratamento farmacológico , Dasatinibe , Avaliação de Medicamentos , Feminino , Camundongos , Camundongos Pelados , Camundongos Endogâmicos BALB C , Oxazolona
11.
Cryobiology ; 65(3): 319-25, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22981976

RESUMO

The present study aimed to evaluate the effect of methyl-ß-cyclodextrin (MßCD) as a cholesterol loader to change oocyte plasma membrane and increase its tolerance toward cryopreservation. The first and second experiments were conducted to investigate if MßCD could improve nuclear and cytoplasmic maturation after oocyte exposure to cold stress for 10 or 30 min, respectively. No differences (P>0.05) in either experiment in the metaphase II (MII) rate of oocytes exposed to MßCD and cold stress; but these oocytes presented lower maturation rates than control groups. In the second experiment, a lower percentage of oocytes showed degenerated chromatin (P<0.05) after exposure to 2mg/mL of MßCD compared to the group exposed to 0mg/mL. However, no differences among treatments were observed in cytoplasmic maturation. Groups exposed to cold stress demonstrated a lower (P<0.05) capacity for embryonic development compared to the control groups. In the third experiment immature oocytes were exposed to MßCD and then, vitrified (cryotop). After warming, we observed that the ability to reach MII and chromatin degeneration were altered (P<0.05) by MßCD. The blastocysts rate (P<0.05) on D7 was higher in the 2 mg/mL MßCD group, but an identical finding was not observed on D8 (P>0.05). Chromatin degeneration was higher in the vitrification groups. We conclude that MßCD improved nuclear maturation by reducing oocyte degeneration after cold stress or vitrification; however, more studies are required to clarify the usefulness of MßCD use in oocyte cryopreservation.


Assuntos
Colesterol/administração & dosagem , Criopreservação/métodos , Portadores de Fármacos/metabolismo , Oócitos/citologia , Vitrificação , beta-Ciclodextrinas/metabolismo , Animais , Bovinos , Sobrevivência Celular , Temperatura Baixa , Técnicas de Cultura Embrionária , Feminino , Fertilização in vitro , Masculino , Oócitos/metabolismo
12.
Phys Rev Lett ; 108(19): 191802, 2012 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-23003027

RESUMO

The RENO experiment has observed the disappearance of reactor electron antineutrinos, consistent with neutrino oscillations, with a significance of 4.9 standard deviations. Antineutrinos from six 2.8 GW(th) reactors at the Yonggwang Nuclear Power Plant in Korea, are detected by two identical detectors located at 294 and 1383 m, respectively, from the reactor array center. In the 229 d data-taking period between 11 August 2011 and 26 March 2012, the far (near) detector observed 17102 (154088) electron antineutrino candidate events with a background fraction of 5.5% (2.7%). The ratio of observed to expected numbers of antineutrinos in the far detector is 0.920±0.009(stat)±0.014(syst). From this deficit, we determine sin(2)2θ(13)=0.113±0.013(stat)±0.019(syst) based on a rate-only analysis.

13.
Mol Biol (Mosk) ; 44(5): 847-52, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21090171

RESUMO

Chang-liver cells is a cell line generated from human liver tissue, which is often used in scientific research. ADAMs are a family of proteins that consist of multi-domains, possess multi-functions and play a central role in normal or abnormal physiological conditions, such as regeneration and tumorigenesis. To investigate the expression and functional alteration of the ADAMs or ADAM related proteins in Chang-liver cells, this cell line was treated with heat stress, modified Hanks solution containing ATP or other buffers. Our results showed that the treatment with Hanks solution containing ATP induces Chang-liver cells to express new ADAM related proteins. To analyze these new ADAM related proteins, a cDNA expression library was constructed for the treated Chang-liver cells. A series of positive clones were obtained through immunoscreening with an ADAMs common antibody. A new ADAM related protein possessing alkaline protease activity was confirmed in these clones.


Assuntos
Proteínas ADAM/biossíntese , Trifosfato de Adenosina/farmacologia , Resposta ao Choque Térmico/efeitos dos fármacos , Resposta ao Choque Térmico/fisiologia , Fígado/metabolismo , Linhagem Celular , Indução Enzimática/efeitos dos fármacos , Indução Enzimática/fisiologia , Biblioteca Gênica , Humanos
14.
Anim Reprod Sci ; 67(3-4): 153-8, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11530261

RESUMO

The main objectives of this investigation were to monitor the birth weight of calves and gestation length following artificial insemination (AI) and transfer of in vivo or in vitro produced Korean native, Hanwoo embryos. Embryos produced in vivo were recovered from uterine flushings of superovulated cows 7 days after AI. Those embryos produced in vitro were co-cultured with cumulus cells for 7-8 days after in vitro fertilization. The birth weights of calves following the transfer of in vitro produced (IVP) embryos were heavier than calves from both of AI- and in vivo-derived embryo transferred calves in both sexes (29.6, 24.1 and 25.2kg, respectively, P<0.05). The IVP calves also had a longer gestation length (293.9, 285.8 and 283.8 days, respectively, P<0.05).


Assuntos
Transferência Embrionária/veterinária , Fertilização in vitro/veterinária , Animais , Peso ao Nascer , Bovinos , Feminino , Idade Gestacional , Inseminação Artificial/veterinária , Gravidez
15.
Planta Med ; 67(3): 277-9, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11345703

RESUMO

The fractionation of Eugenia caryophyllata (Myrtaceae) guided by the syncytia formation inhibition assay led to the isolation of four tannins (eugeniin, casuarictin, 1,3-di-O-galloyl-4,6-(S)-hexahydroxydiphenoyl-beta-D-glucopyranose, and tellimagrandin I), and two chromones (biflorin and isobiflorin). Among the isolated compounds, tellimagrandin (4) showed a significantly high inhibitory activity on the syncytia formation with an IC50 value of 16.12 +/- 1.98 micrograms/ml.


Assuntos
Cromonas/isolamento & purificação , Células Gigantes/efeitos dos fármacos , HIV-1/efeitos dos fármacos , Rosales/química , Taninos/isolamento & purificação , Cromonas/química , Cromonas/farmacologia , Células Gigantes/metabolismo , Proteína gp120 do Envelope de HIV/efeitos dos fármacos , Fusão de Membrana/efeitos dos fármacos , Extratos Vegetais/química , Brotos de Planta/química , Taninos/química , Taninos/farmacologia
16.
Arch Pharm (Weinheim) ; 334(11): 345-50, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11822171

RESUMO

In this study, C-2, C-8, N-9 substituted 6-(3-chloroanilino)purine derivatives were synthesized and their inhibitory effects on cyclin-dependent kinases (CDK2, 4) as well as their cytotoxicities were evaluated. The effects of substituents at the C-2, C-8, and N-9 positions of the substituted purine were investigated. Among the compounds tested, [6-(3-chloroanilino)-2-(2-hydroxymethyl-4-hydroxypyrrolidyl)-9- isopropylpurine] (4h) was the most active inhibitor of CDK2 with IC50 of 0.3 microM, i.e. a two-fold increased inhibitory activity as compared to roscovitine. Results from structure-activity relationship studies should allow the design of more potent and selective CDK2 inhibitors, which may provide an effective therapy for cancer or other CDK-dependant diseases.


Assuntos
Quinases Ciclina-Dependentes/antagonistas & inibidores , Purinas/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/farmacologia , Humanos , Concentração Inibidora 50 , Purinas/síntese química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
17.
Arch Pharm (Weinheim) ; 334(11): 357-60, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11822173

RESUMO

The 4-anilinoquinazoline PD 153035 (1) is a potential antitumor agent which acts by inhibiting tyrosine kinase activity of epidermal growth factor receptor (EFGR) via competitive binding at the ATP site of enzyme. A series of cyclic analogues of PD 153035 bearing the 1,4-dioxane ring was prepared by reaction of 6-chloro derivative 5 with several aniline nucleophiles. These were evaluated for their ability to inhibit the EGFR kinase and the growth of primary human tumor cell cultures. All of the new 4-anilinoquinazolines exhibited less potency than PD 153035 against EGFR kinase. However, compounds 2b, 2c, 2e, 2g, and 2h showed higher inhibitory activities than PD 153035 against the growth of A431 tumor cell line. The compound 2b containing 3-chloroaniline ring was as potent as PD 153035 against EGFR kinase and showed about 5.4-fold better potency than PD153035 in the inhibition of growth of A431 cell line with good selectivity.


Assuntos
Antineoplásicos/síntese química , Quinazolinas/farmacologia , Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Dioxanos , Receptores ErbB/antagonistas & inibidores , Humanos , Proteínas Tirosina Quinases/antagonistas & inibidores , Quinazolinas/síntese química , Relação Estrutura-Atividade , Células Tumorais Cultivadas
18.
Arch Pharm (Weinheim) ; 332(6): 187-90, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10399486

RESUMO

In this study, C-2, N-9 substituted 6-benzylaminopurine derivatives were synthesized and their inhibitory effects on cyclin-dependent kinase (CDK2) were evaluated. The effect of substituents at the C-2 and N-9 positions of substituted purine was investigated. Among the compounds tested, compound 7b-iii (6-benzylamino-2-thiomorpholinyl-9-isopropylpurine) was the most active inhibitor (IC50 = 0.9 microM). Compound 7b-iii showed 10-fold higher activity compared to olomoucine and almost the same activity as roscovitine. Results from structure-activity relationship studies should allow the design of more potent and selective CDK inhibitors, which may provide an effective therapy for cancer or other CDK dependent diseases.


Assuntos
Antineoplásicos/síntese química , Quinases relacionadas a CDC2 e CDC28 , Quinases Ciclina-Dependentes/antagonistas & inibidores , Inibidores Enzimáticos/síntese química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Purinas/síntese química , Antineoplásicos/farmacologia , Quinase 2 Dependente de Ciclina , Inibidores Enzimáticos/farmacologia , Humanos , Purinas/farmacologia , Relação Estrutura-Atividade
19.
Vox Sang ; 76(4): 226-30, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10394142

RESUMO

OBJECTIVE: For years, blood transfusion centers in Taiwan have used the Quantitative Buffy Coat (QBC(R)) Hematology System for platelet counts on capillary blood samples in the laboratory screening of apheresis donors. The system has not been evaluated for the prediction of yields in plateletpheresis. Methods : The QBC instrument was evaluated for reproducibility of platelet counts and compared with five electronic cell counters. We also collected both capillary and venous blood from voluntary donors before donation and counted platelets, comparing the QBC system and an electronic blood cell counter (Sysmex K1000). The correlation between donors' predonation platelet counts and plateletpheresis yields was analyzed. RESULTS: The R values for platelet counts between the QBC Hematology System and other electronic counters are lower (0.759-0. 890) than among the electronic counters (0.929-0.973). The mean capillary platelet count and the mean venous platelet count were 241. 9+/-50.3x10(3)/microl and 233.2 +/-47.9x10(3)/microl by the QBC system, and 244.9+/-54.1x10(3)/microl and 218.9+/-46.5x10(3)/microl by the Sysmex K1000, respectively. Linear regression analysis showed that platelet yields correlated well with donors' predonation platelet counts using the Sysmex K1000 counter (R = 0.777- 0.890, p<0.001), but not with the QBC system (R = 0.326 approximately 0.755, p<0.05). CONCLUSION: The QBC Hematology System is not accurate enough to determine predonation platelet counts that are to be used for calculating the number of processing cycles for plateletpheresis.


Assuntos
Contagem de Plaquetas/métodos , Plaquetoferese , Eletrônica , Estudos de Avaliação como Assunto , Humanos , Modelos Lineares , Contagem de Plaquetas/instrumentação , Plaquetoferese/normas , Reprodutibilidade dos Testes
20.
Ultrastruct Pathol ; 21(4): 393-404, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9206004

RESUMO

The study was performed to determine the ultrastructural characteristics of central neurocytoma and its features in primary cell culture. Fresh tissue from three tumors was mechanically and enzymatically dissociated into individual cells, which were cultured onto poly-L-lysine precoated Aclar coverslips in the media. The tumor cells attached to the surface of the coverslips within 12 to 24 h and delicate cytoplasmic processes developed within 2 to 3 days. Electron microscopic examination of the cultured tumor cells and the tumor tissue supported neuronal origin. Combined tissue culture and electron microscopic study provides a rapid, reliable, and reproducible means for the diagnosis of central neurocytoma.


Assuntos
Neoplasias Encefálicas/ultraestrutura , Ventrículos Cerebrais/ultraestrutura , Neurocitoma/ultraestrutura , Adolescente , Adulto , Neoplasias Encefálicas/terapia , Feminino , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética , Masculino , Microscopia Eletrônica , Neurocitoma/terapia , Células Tumorais Cultivadas
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