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1.
Front Plant Sci ; 14: 1099110, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36890885

RESUMO

Background: Considerable attention has been given to how different aspects of biodiversity sustain ecosystem functions. Herbs are a critical component of the plant community of dryland ecosystems, but the importance of different life form groups of herbs is often overlooked in experiments on biodiversity-ecosystem multifunctionality. Hence, little is known about how the multiple attributes of diversity of different life form groups of herbs affect changes to the multifunctionality of ecosystems. Methods: We investigated geographic patterns of herb diversity and ecosystem multifunctionality along a precipitation gradient of 2100 km in Northwest China, and assessed the taxonomic, phylogenetic and functional attributes of different life form groups of herbs on the multifunctionality. Results: We found that subordinate (richness effect) species of annual herbs and dominant (mass ratio effect) species of perennial herbs were crucial for driving multifunctionality. Most importantly, the multiple attributes (taxonomic, phylogenetic and functional) of herb diversity enhanced the multifunctionality. The functional diversity of herbs provided greater explanatory power than did taxonomic and phylogenetic diversity. In addition, the multiple attribute diversity of perennial herbs contributed more than annual herbs to multifunctionality. Conclusions: Our findings provide insights into previously neglected mechanisms by which the diversity of different life form groups of herbs affect ecosystem multifunctionality. These results provide a comprehensive understanding of the relationship between biodiversity and multifunctionality, and will ultimately contribute to multifunctional conservation and restoration programs in dryland ecosystems.

2.
Sci Rep ; 9(1): 9953, 2019 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289294

RESUMO

This study was performed to examine the quality of planning and treatment modality using a CyberKnife (CK) robotic radiosurgery system with multileaf collimator (MLC)-based plans and IRIS (variable aperture collimator system)-based plans in relation to the dose-response of secondary cancer risk (SCR) in patients with benign intracranial tumors. The study population consisted of 15 patients with benign intracranial lesions after curative treatment using a CyberKnife M6 robotic radiosurgery system. Each patient had a single tumor with a median volume of 6.43 cm3 (range, 0.33-29.72 cm3). The IRIS-based plan quality and MLC-based plan quality were evaluated by comparing the dosimetric indices, taking into account the planning target volume (PTV) coverage, the conformity index (CI), and the dose gradient (R10% and R50%). The dose-response SCR with sarcoma/carcinoma induction was calculated using the concept of the organ equivalent dose (OED). Analyses of sarcoma/carcinoma induction were performed using excess absolute risk (EAR) and various OED models of dose-response type/lifetime attributable risk (LAR). Moreover, analyses were performed using the BEIR VII model. PTV coverage using both IRIS-based plans and MLC-based plans was identical, although the CI values obtained using the MLC-based plans showed greater statistical significance. In comparison with the IRIS-based plans, the MLC-based plans showed better dose falloff for R10% and R50% evaluation. The estimated difference between Schneider's model and BEIR VII in linear-no-threshold (Lnt) cumulative EAR was about twofold. The average values of LAR/EAR for carcinoma, for the IRIS-based plans, were 25% higher than those for the MLC-based plans using four SCR models; for sarcoma, they were 15% better in Schneider's SCR models. MLC-based plans showed slightly better conformity, dose gradients, and SCR reduction. There was a slight increase in SCR with IRIS-based plans in comparison with MLC-based plans. EAR analyses did not show any significant difference between PTV and brainstem analyses, regardless of the tumor volume. Nevertheless, an increase in target volume led to an increase in the probability of SCR. EAR showed statistically significant differences in the soft tissue according to tumor volume (1-10 cc and ≥10 cc).


Assuntos
Algoritmos , Neoplasias Encefálicas/cirurgia , Segunda Neoplasia Primária/etiologia , Radiocirurgia/efeitos adversos , Planejamento da Radioterapia Assistida por Computador/normas , Medição de Risco/métodos , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Adolescente , Adulto , Idoso , Neoplasias Encefálicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Segunda Neoplasia Primária/patologia , Prognóstico , Radioterapia de Intensidade Modulada/efeitos adversos , Estudos Retrospectivos , Adulto Jovem
3.
Int J Mol Sci ; 19(4)2018 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-29565268

RESUMO

Hinokitiol, a natural monoterpenoid from the heartwood of Calocedrus formosana, has been reported to have anticancer effects against various cancer cell lines. However, the detailed molecular mechanisms and the inhibiting roles of hinokitiol on adenocarcinoma A549 cells remain to be fully elucidated. Thus, the current study was designed to evaluate the effect of hinokitiol on the migration of human lung adenocarcinoma A549 cells in vitro. The data demonstrates that hinokitiol does not effectively inhibit the viability of A549 cells at up to a 10 µM concentration. When treated with non-toxic doses (1-5 µM) of hinokitiol, the cell migration is markedly suppressed at 5 µM. Hinokitiol significantly reduced p53 expression, followed by attenuation of Bax in A549 cells. A dose-dependent inhibition of activated caspase-9 and -3 was observed in the presence of hinokitiol. An observed increase in protein expression of matrix metalloproteinases (MMPs) -2/-9 in A549 cells was significantly inhibited by hinokitiol. Remarkably, when A549 cells were subjected to hinokitiol (1-5 µM), there was an increase in the activities of antioxidant enzymes catalase (CAT) and superoxide dismutase (SOD) from the reduction in cells. In addition, the incubation of A549 cells with hinokitiol significantly activated the cytochrome c expression, which may be triggered by activation of caspase-9 followed by caspase-3. These observations indicate that hinokitiol inhibited the migration of lung cancer A549 cells through several mechanisms, including the activation of caspases-9 and -3, induction of p53/Bax and antioxidant CAT and SOD, and reduction of MMP-2 and -9 activities. It also induces cytochrome c expression. These findings demonstrate a new therapeutic potential for hinokitiol in lung cancer chemoprevention.


Assuntos
Metaloproteinases da Matriz/metabolismo , Monoterpenos/farmacologia , Tropolona/análogos & derivados , Células A549 , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Catalase/metabolismo , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Citocromos c/metabolismo , Humanos , Metaloproteinase 2 da Matriz/metabolismo , Superóxido Dismutase/metabolismo , Tropolona/farmacologia
4.
Appl Microbiol Biotechnol ; 97(17): 7659-67, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23807665

RESUMO

(S)-(+)-2,2-Dimethylcyclopropane carboxylic acid [(S)-(+)-DMCPA] is a key chiral intermediate for production of Cilastatin, an excellent renal dehydropeptidase-I inhibitor. In this study, a new method for preparation of (S)-(+)-DMCPA with microbial esterases was investigated. A microbial screening program obtained six esterase-producing isolates that could display relatively high activities and enantioselectivities using racemic ethyl 2,2-dimethylcyclopropane carboxylate (DMCPE) as screening substrate, aiming at forming optically pure (S)-(+)-DMCPA. Further selection was carried out with substrates having different alcohol moieties, including methyl, ethyl, and 2-chloroethyl esters. Finally, one of these strains, numbered ECU1013, with high enantioselectivity toward the hydrolytic resolution of methyl 2,2-dimethylcyclopropane carboxylate (DMCPM), afforded the (S)-product in 92 % ee, and was later identified as Rhodococcus sp. According to our research, there were several active esterases to DMCPM in cells of Rhodococcus sp. ECU1013; however, (S)-preferential esterase was selectively enriched based on the time-dependent profile of esterases biosynthesis, thereby the enantiomeric excess of biotransformation product (ee p) was constantly increased, finally maintained at 95 % (S). To improve the yield, various organic solvents were employed for better dispersion of the hydrophobic substrate. As a result, (±)-DMCPM of up to 400 mM in the organic phase of isooctane was enantioselectively hydrolyzed into (S)-(+)-DMCPA, with an isolation yield of 38 % and a further increase of ee p to 99 %.


Assuntos
Cilastatina/metabolismo , Ciclopropanos/metabolismo , Rhodococcus/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Ciclopropanos/química , Esterases/genética , Esterases/metabolismo , Hidrólise , Dados de Sequência Molecular , Filogenia , Rhodococcus/classificação , Rhodococcus/enzimologia , Rhodococcus/isolamento & purificação , Microbiologia do Solo , Estereoisomerismo
5.
Zhonghua Zhong Liu Za Zhi ; 29(5): 346-50, 2007 May.
Artigo em Chinês | MEDLINE | ID: mdl-17892129

RESUMO

OBJECTIVE: To explore the effects of human FRNK gene on E-cadherin/beta-catenin complex in colon cancer cell line Colo320WT cells stimulated with extrinsic gastrinl7. METHODS: AdEasy system was used to construct pAdhFRNK expressing human FRNK gene by recombination in E. coli. BJ5283. pCR3.1/GR plasmid expressing gastrin receptor CCK-2 was transfected into colon cancer cell line Colo320 cells by Lipofectamine 2000 and expressing stably CCK-2R clones were screened by G418 (500 pg/ml). The expression levels of gastrin receptor in Colo320 cells and the transfected Colo320WT cells were assayed by RT-PCR. Colo320WT cells were treated by 10(-8) mol/L gastrinl7 for 12 h; and after Colo320WT cells were infected by pAdhFRNK (MOI: 100) for 2 d the cells were treated by gastrin17 for 12 h again. The expression levels of E-cadherin and beta-catenin in TX-100 soluble fraction and TX-100 insoluble fraction of Colo320WT cells were assayed by co-immunoprecipation and Western blot. E-cadherin and beta-catenin's distribution in Colo320WT cells were detected by immunocytochemistry. RESULTS: When 10(-8) mol/L gastrin17 stimulated Colo320WT cells for 12 h, the expression levels of E-cadherin and beta-catenin in TX-100-soluble fraction decreased apparently, while the expression levels of E-cadherin and beta-catenin in TX-100-insoluble fraction increased markedly. When pAdhFRNK infected Colo320WT cells for 2 d and 10(-8) mol/L gastrin17 treated the cells for 12 h, the expression levels of E-cadherin and beta-catenin in TX-100-soluble fraction increased apparently again, and the expression levels of E-cadherin and beta-catenin in TX-100-insolutble fraction decreased markedly. Immunocytochemistry showed that the distribution of E-cadherin and beta-catenin was translocated from plasma membrane into cytoplasm and nucleus in the cells stimulated with gastrinl7, and after the cells were infected with pAdhFRNK and stimulated by gastrinl7 again. beta-catenin was mainly observed in cytoplasm and little nuclear immunoreactivity. CONCLUSION: An adenovirus vector pAdhFRNK can inhibit abnormal distribution of E-cadherin and beta-catenin in the gastrin17-stimulated cells. The mechanism is probably that hFRNK can disphosphorylate phosphorylated FAK and block FAK pathway.


Assuntos
Caderinas/metabolismo , Gastrinas/farmacologia , Proteínas Tirosina Quinases/metabolismo , beta Catenina/metabolismo , Adenoviridae/genética , Western Blotting , Linhagem Celular Tumoral , Membrana Celular/metabolismo , Núcleo Celular/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Citoplasma/metabolismo , Vetores Genéticos/química , Vetores Genéticos/genética , Humanos , Imuno-Histoquímica , Imunoprecipitação , Lipídeos/química , Ligação Proteica , Transporte Proteico/efeitos dos fármacos , Proteínas Tirosina Quinases/genética , Receptor de Colecistocinina B/genética , Receptor de Colecistocinina B/metabolismo , Transfecção/métodos
6.
World J Gastroenterol ; 12(46): 7482-7, 2006 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-17167838

RESUMO

AIM: To explore the effect of gastrin 17 (G17) on beta-catenin/T cell factor-4 (Tcf-4) signaling in colonic cancer cell line Colo320WT. METHODS: The pCR3.1/GR plasmid, which expresses gastrin receptor, cholecystokinin-2 receptor (CCK-2R), was transfected into a colonic cancer cell line Colo320 by Lipofectamine (TM)2000 and the stably expressing CCK-2R clones were screened by G418. The expression levels of gastrin receptor in the Colo320 and the transfected Colo320WT cell line were assayed by RT-PCR. Colo320WT cells were treated with G17 in a time-dependent manner (0, 1, 6, 12, 24 and 48 h), then with L365,260 (Gastrin(17) receptor blocker) for 30 min, and with G17 again for 12 h or L365,260 for 12 h. Expression levels of beta-catenin in a TX-100 soluble fraction and TX-100 insoluble fraction of Colo320WT cells treated with G17 were detected by co-immuniprecipation and Western blot. Immunocytochemistry was used to examine the distribution of beta-catenin in CoLoWT320 cells. Expression levels of c-myc and cyclin D1 in Colo320WT cells treated with G17 were assayed by Western blot. RESULTS: Expression levels of beta-catenin in the TX-100 solution fraction decreased apparently in a time-dependent fashion and reached the highest level after G17 treatment for 12 h, while expression levels of beta-catenin in the TX-100 insoluble fraction were just on the contrary. Immunocytochemistry showed that beta-catenin was translocated from the cell membranes into the cytoplasm and nucleus under G17 treatment. Expression levels of c-myc and cyclin D1 in the G17-treated Colo320WT cells were markedly higher compared to the untreated Colo320WT cells. In addition, the aforementioned G17-stimulated responses were blocked by L365,260. CONCLUSION: Gastrin17 activates beta-catenin/Tcf-4 signaling in Colo320WT cells, thereby leading to over-expression of c-myc and cyclin D1.


Assuntos
Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Gastrinas/farmacologia , Fatores de Transcrição TCF/metabolismo , beta Catenina/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Neoplasias do Colo/genética , Ciclina D , Ciclinas/metabolismo , DNA Complementar/genética , Humanos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Receptor de Colecistocinina B/genética , Receptor de Colecistocinina B/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteína 2 Semelhante ao Fator 7 de Transcrição , Transfecção
7.
J Cutan Pathol ; 30(3): 206-10, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12641782

RESUMO

Tubulopapillary hidradenoma (TPH)1 is a term proposed to describe morphological dermal ductal tumors with both eccrine and apocrine differentiation. The term TPH encompasses a spectrum of lesions that includes tubular apocrine adenoma (TAA) and papillary eccrine adenoma (PEA):2 PEA and TAA can be indistinguishable both clinically and histologically. We described a case of TPH with both prominent eccrine and apocrine differentiation combined with syringocystadenoma papilliferum (SCAP) over the distal extremity. This rarely encountered dermatopathological phenomenon is the sixth reported case from the literature in which PEA or TAA and SCAP were present in the same lesion.3-7 Furthermore, the tumor had a warty surface, which is histologically consistent with a typical viral verruca. Although PCR and DNA probe hybridization for human papilloma virus (HPV) types 2, 6/11, 16 and 18 failed to reveal positive results, the location and clinicopathologic correlation convinced us that superimposed HPV could not be excluded.


Assuntos
Adenoma de Glândula Sudorípara/patologia , Carcinoma Verrucoso/patologia , Cistadenoma Papilar/patologia , Neoplasias das Glândulas Sudoríparas/patologia , Adenoma de Glândula Sudorípara/química , Adenoma de Glândula Sudorípara/cirurgia , Adulto , Biomarcadores Tumorais/química , Carcinoma Verrucoso/química , Carcinoma Verrucoso/cirurgia , Cistadenoma Papilar/química , Cistadenoma Papilar/cirurgia , Humanos , Imuno-Histoquímica , Masculino , Neoplasias das Glândulas Sudoríparas/química , Neoplasias das Glândulas Sudoríparas/cirurgia
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