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1.
Nat Commun ; 9(1): 2368, 2018 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-29915250

RESUMO

Complex tissue-specific and cell-specific signaling by the estrogen receptor (ER) frequently leads to the development of resistance to endocrine therapy for breast cancer. Pure ER antagonists, which completely lack tissue-specific agonist activity, hold promise for preventing and treating endocrine resistance, however an absence of structural information hinders the development of novel candidates. Here we synthesize a small panel of benzopyrans with variable side chains to identify pure antiestrogens in a uterotrophic assay. We identify OP-1074 as a pure antiestrogen and a selective ER degrader (PA-SERD) that is efficacious in shrinking tumors in a tamoxifen-resistant xenograft model. Biochemical and crystal structure analyses reveal a structure activity relationship implicating the importance of a stereospecific methyl on the pyrrolidine side chain of OP-1074, particularly on helix 12.


Assuntos
Antineoplásicos/farmacologia , Benzopiranos/farmacologia , Antagonistas de Estrogênios/farmacologia , Neoplasias Mamárias Experimentais/tratamento farmacológico , Pirrolidinas/farmacologia , Fosfatase Alcalina/análise , Animais , Antineoplásicos/análise , Antineoplásicos/síntese química , Antineoplásicos/uso terapêutico , Benzopiranos/síntese química , Benzopiranos/química , Benzopiranos/uso terapêutico , Proliferação de Células/efeitos dos fármacos , Antagonistas de Estrogênios/análise , Antagonistas de Estrogênios/síntese química , Antagonistas de Estrogênios/uso terapêutico , Receptor alfa de Estrogênio/efeitos dos fármacos , Feminino , Humanos , Células MCF-7 , Camundongos Endogâmicos BALB C , Camundongos Nus , Conformação Proteica em alfa-Hélice/efeitos dos fármacos , Pirrolidinas/química , Pirrolidinas/uso terapêutico , Moduladores Seletivos de Receptor Estrogênico/análise , Moduladores Seletivos de Receptor Estrogênico/síntese química , Moduladores Seletivos de Receptor Estrogênico/farmacologia , Estereoisomerismo , Útero/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
2.
J Virol Methods ; 258: 29-34, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29753708

RESUMO

The Potyvirus genus is one of the largest genera of plant viruses and encompasses many economically important pathogens. While a number of degenerate primers for use in broad spectrum RT-PCR assays have been published, it is not clear which of these primers would be the most useful for use by plant diagnostic laboratories. Twelve sets of primers were tested for their ability to detect nine potyviruses in a two-step RT-PCR. Viruses were extracted from different host backgrounds and were selected to represent eight clades plus one species between clades (sensu Gibbs and Ohshima, 2010). Results of this study indicated that the primers CIFor/CIRev produced easily detectable amplicons from all nine potyviruses without non-specific amplification, false positives, or false negatives. CIFor/CIRev produced single amplicons from potyvirus-infected tissues which could be sequenced directly without gel purification to identify the virus to species.


Assuntos
Primers do DNA/genética , Técnicas de Diagnóstico Molecular/métodos , Doenças das Plantas/virologia , Potyvirus/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Potyvirus/genética , Sensibilidade e Especificidade
3.
Phys Chem Chem Phys ; 15(16): 6068-79, 2013 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-23493900

RESUMO

Evolution of electronic properties and the nature of bonding of the 4d-transition metal silicides (ZrSi, NbSi, MoSi and PdSi) are discussed, revealing interesting trends in the transition metal-silicon interactions across the period. The electronic properties of select transition metal silicide diatomics have been determined by anion photoelectron imaging spectroscopy and theoretical methods. The electron binding energy spectra and photoelectron angular distributions obtained by 2.33 eV (532 nm) photons have revealed the distinct features of these diatomics. The theoretical calculations were performed at the density functional theory (DFT) level using the unrestricted B3LYP hybrid functional and at the ab initio unrestricted coupled cluster singles and doubles (triplets) (UCCSD(T)) methods to assign the ground electronic states of the neutral and anionic diatomics. The excited electronic states were calculated by the DFT (TD-DFT)/UB3LYP method. We have observed that the valence molecular orbital configuration of the ZrSi and NbSi anions are significantly different from that of the MoSi and PdSi anions. By combining our experimental and theoretical results, we report that the composition of the highest occupied molecular orbitals shift from a majority of transition metal s- and d-orbital contribution in ZrSi and NbSi, to mainly silicon p-orbital contribution for MoSi and PdSi. We expect these observed atomic scale transition metal-silicon interactions to be of increasing importance with the miniaturization of devices approaching the sub-nanometer size regime.

4.
Plant Dis ; 97(10): 1378, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30722174

RESUMO

Sentinel plots for monitoring Asian soybean rust (ASR) caused by Phakopsora pachyrhizi Syd. were initiated in 2005 at Isabela (EEI), Adjuntas (EEA), and Juana Diaz (EEJD) experiment stations. Until 2009, no signs or symptoms of ASR were observed in soybean (Glycine max [L.] Merr.) or common bean (Phaseolus vulgaris L.). These sites were found to be negative for the occurrence of ASR based on PCR with specific primers Ppa1 and Ppa2 (2). However, P. meibomiae, the cause of American soybean rust (AmSR) endemic to this region, was found in Adjuntas naturally infecting numerous wild and cultivated legumes, particularly Lablab purpureus (3). Symptoms of AmSR in L. purpureus appeared as reddish-brown spots on the underside of the leaves with three to four uredia per lesion. On February 12, 2011, leaf samples of soybean in beginning pod-fill (R5) and beginning-maturity (R8) growth stages were collected in a winter nursery at EEI and found to have small brown specks with chlorotic haloes on the underside of the leaves and leaf sections from symptomatic areas indicated an abundance of uredinia. Under the light microscope, urediniospores observed at 40× were morphologically similar to Phakopsora spp. Total DNA was extracted from leaf discs using the Qiagen DNeasy Plant Mini Kit following the methods of Frederick et al. (2). Detection of ASR pathogen was achieved via PCR amplification with Ppa1 and Ppa2 primers that are specific for P. pachyrhizi Syd. After sequencing the amplicon, BLAST analysis of the internal transcribed spacer (ITS) region of the ribosomal RNA genes indicated 100% identity with known P. pachyrhizi sequences in GenBank. The sequence of isolate P. pachyrhizi EEI-2011 was submitted to GenBank as JX994293. No amplification was observed after PCR with species-specific primers Pme1 and Pme2 specific for P. meibomiae (Arthur) Arthur. L. purpureus collected from EEA and Utuado only appears to be infected by P. meibomiae and no mixed infections with P. pachyrhizi were apparent, based on the PCR test. Leaf samples from EEI were sent to the UF Plant Diagnostic Center in Gainesville, FL, where quantitative PCR with primers Ppa1 and Ppa2 confirmed the presence of P. pachyrhizi; while P. meibomiae was not detected with primers Pme1 and Pme2. Pathogenicity tests were conducted on the soybean cv. Williams with isolate EEI-2011. Fifteen-day-old soybean plants were inoculated by attaching an infected and sporulating 1 cm2 piece of soybean leaf from EEI-2011 with an average of 4.5 × 105 urediniospores per cm2 (1). Inoculated plants were placed in a growth chamber at 20°C night and 28°C day temperatures, 80% humidity, and a 12-h light photoperiod. Small reddish brown spots with chlorotic haloes developed 4 to 6 days after inoculation and tan lesions appeared 10 to 15 days later. Mature tan lesions developed in 2 weeks with an average of 2.4 uredinia/lesion. Urediniospores were observed with light microscope and these were morphologically similar to those spores observed in the original diseased samples. Another PCR test confirmed P. pachyrhizi after amplification with the species-specific primers. The pathogenicity test was repeated twice with the same cultivar. To our knowledge, this is the first report of ASR in Puerto Rico and this finding will have implications as another overwintering site for Asian soybean rust in the Caribbean region. References: (1) C. Estévez de Jensen et al. J. Agric. Univ. P.R. 93:125, 2009. (2) R. D. Frederick et al. Phytopathology 92:217, 2002. (3) B. Vega and C. Estévez de Jensen. J. Agric. Univ. P.R. 94:211, 2010.

5.
J Chem Phys ; 136(21): 214314, 2012 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-22697550

RESUMO

We report a combined experimental and theoretical photoelectron spectroscopy study of ZnOH(-). We find that the electron binding energy spectrum of ZnOH(-) reveals a broad and featureless peak between 1.4 and 2.4 eV in energy. The vertical detachment energy (VDE) of ZnOH(-) is determined to be 1.78 eV, which is lower than the 2.08 eV VDE of ZnO(-). Our theoretical calculations match the VDE of ZnOH(-) accurately, but we find that the broadness of the peak cannot be explained by rotational or vibrational state excitation. The broadness of this peak is in strong contrast to the narrow and easily understood first peak of the ZnO spectrum, which features a well-resolved vibrational progression that can be readily explained by calculating the Franck-Condon transition factors. This study provides spectroscopic evidence of the effect of hydrogen on diatomic ZnO.

6.
Plant Dis ; 95(4): 485-489, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30743333

RESUMO

Field studies to quantify the effects of shade intensity and duration on soybean rust caused by Phakopsora pachyrhizi were carried out in Florida in 2006 and 2007. Soybean plants at the V4 stage were inoculated with urediniospores at 2100, 0000, and 0200 h. Inoculated plants were either placed in cages that were covered with shade cloths of different mesh sizes allowing 70, 50, or 20% transmission of sunlight or were not covered so that the plants received 100% of sunlight. Plants kept under 20 and 100% sunlight were sampled 12, 18, and 36 h after inoculation to determine the in vivo germination percentage of urediniospores and the percentage of germ tubes that formed appressoria. In separate experiments, inoculated plants were placed under the shade (20% sunlight) and moved to unshaded conditions after 1, 2, and 7 days. For all experiments, soybean rust incidence and severity were rated 12 days after inoculation. Higher levels of disease incidence and severity were detected in plants under shade compared with those under full sunlight. Shade duration greater than 2 days favored disease development. Within 36 h, in vivo germination of urediniospores and formation of appressoria were not significantly affected by the treatments. These results may explain why soybean rust is more severe in the lower canopy and shaded areas in the field.

7.
Plant Dis ; 92(10): 1472, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30769555

RESUMO

Soybean rust (SBR), caused by the obligate fungus Phakopsora pachyrhizi Syd. & P. Syd., was initially reported on soybean (Glycine max L.) in Louisiana in 2004 and has since been reported on soybean and/or kudzu (Pueraria lobata (Willd.) Ohwi) in 9 states in 2005, 15 states in 2006, and 19 states in 2007 (1). The host range of P. pachyrhizi includes plants that are all in the Fabaceae or legume family. Six plant species in the United States have been reported as hosts of P. pachyrhizi: soybean, kudzu, Florida beggarweed (Desmodium tortuosum (Sw) DC.), dry bean (Phaseolus vulgaris L.), lima bean (P. lunatus L.), and scarlet runner bean (P. coccineus L.) (4). On 17 April 2008, a rust disease was observed on a weedy legume host with red showy flowers that was growing with kudzu in an overgrown vacant lot in the understory of live oak trees (Quercus virginiana Mill.) in Citra, FL. The discovery was made during routine scouting of this Integrated Pest Management Pest Information Platform for Extension and Education (IPM PIPE) mobile sentinel plot (3). The plant was confirmed by University of Florida botanists to be Erythrina herbaceae L., commonly known as coral bean. Coral bean is native to the southeastern United States and also is planted as a perennial ornamental. A sample of leaves exhibiting rust pustules characteristic of P. pachyrhizi uredinia was collected and examined with a microscope. Brown-to-brick red, angular lesions that were 3 to 11 mm in diameter (average 6.75 mm) were observed on the undersides of the leaves of two trifoliates. Within these lesions, there were several uredinia, some exuding hyaline, echinulate urediniospores (20 × 25 µm). The visual diagnosis and the species of the rust fungus were confirmed to be P. pachyrizi by a real-time PCR protocol (2). The diagnosis on this new host was verified by a USDA, APHIS National Mycologist in Beltsville, MD. Coral bean may serve as an additional overwintering host for P. pachyrhizi in the southeast. To our knowledge, this is the first report of soybean rust caused by P. pachyrhizi on E. herbaceae. References: (1) R. S. C. Christiano and H. Scherm, Phytopathology 97:1428, 2007. (2) R. D. Frederick et al. Phytopathology 92:217, 2002. (3) S. A. Isard et al. Online publication. doi:10.1094/PHP-2006-0915-01-RV. Plant Health Progress, 2006. (4) T. L. Slaminko et al. Plant Dis. 92:767, 2008.

8.
Plant Dis ; 90(7): 970, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30781041

RESUMO

Phakopsora pachyrhizi Syd. & P. Syd., the cause of soybean rust, was first observed in the continental United States in November 2004 (2). During the growing season of 2005, P. pachyrhizi was confirmed on soybean (Glycine max) and/or kudzu (Pueraria montana) in nine states in the southern United States. It is known that P. pachyrhizi has a much larger host range within the Fabaceae family. On 29 September 2005 in Quincy, FL, 45 entries of mostly large-seeded legumes were planted next to soybeans that were infected with P. pachyrhizi. Several seeds of each entry were planted on one hill. Soybean plants growing adjacent to these potential hosts had 15 to 25% of the leaf area affected, 95% incidence, and 73% defoliation on 16 November. On 7 December 2005, all the plants of Phaseolus coccineus L. (scarlet runner bean, PI311827), Phaseolus lunatus L. (lima bean, PI583558), and two Phaseolus vulgaris L. (kidney bean) cvs. Red Hawk and California Early Light Red Kidney (CELRK) were found to have leaves with suspected rust lesions. These plants were at physiological maturity but had not senesced. None of the hosts had been inoculated other than from spores produced by the adjacent rust-infected soybean plants or from unknown locations. On the basis of microscopic examination, suspected infected leaves from plants of the Phaseolus spp. had rust pustules characteristic of P. pachyrhizi uredinia. Uredinia were counted within a randomly selected 2-cm2 area of one leaf of each sample. The mean and range of uredinia per lesion for Phaseolus coccineus was 29 uredinia with a range of 0 to 3 uredinia per lesion, Phaseolus lunatus had 2 uredinia with 0 to 1 uredinium per lesion, Phaseolus vulgaris cv. Red Hawk had 22 uredinia with 0 to 5 uredinia per lesion, and Phaseolus vulgaris cv. CELRK had 43 uredinia with 0 to 4 uredinia per lesion. Polymerase chain reactions using two sets of primers (Ppa1/Ppa2 and Pme1/Pme2) were performed on DNA extracted from leaves of the three species with sporulating rust pustules (1). The results of these tests and further tests conducted by the USDA/APHIS confirmed that P. pachyrhizi was the causal organism for the observed rust. References: (1) P. F. Harmon et al. On-line publication. doi:10.1094/PHP-2005-0613-01-RS. Plant Health Progress, 2005. (2) R. W. Schneider et al. Plant Dis. 89:774, 2005.

9.
Plant Dis ; 90(6): 834, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30781272

RESUMO

Phakopsora pachyrhizi, the causal organism of soybean rust, was first observed in the continental United States on 6 November 2004 (2). On 11 November 2005, as part a national soybean rust monitoring effort, 75 leaves of kudzu (Pueraria montana var. lobata) were arbitrarily collected from a patch growing in Princeton, Caldwell County, Kentucky (37.106650°N, 87.886120°W) that had been periodically scouted for the presence of the disease since May 2005. Upon microscopic examination of the nonincubated sample, a small (˜2.0 cm2) area of one leaf exhibited lesions, uredinia, and urediniospores characteristic of those reported for P. pachyrhizi (the Asian species) and P. meibomiae (the New World species) (2). No other infected leaves were observed despite repeated visits to the site and collection and observation of nearly 200 leaves. On 16 November 2005, one-half of the symptomatic tissue was sent by overnight courier to the USDA/APHIS/PPQ/NIS Laboratory, Beltsville, MD and the other half was sent to the Southern Plant Diagnostic Network Laboratory (SPDN), University of Florida, Gainesville. Both laboratories confirmed that the rust was a Phakopsora spp. on the basis of morphological examination. The preliminary polymerase chain reaction (PCR) testing conducted by the SPDN according to Harmon et al. (1) indicated the presence of P. pachyrhizi that was confirmed by the USDA/NPGBL using the validated modified real-time PCR assay described previously (2). The field diagnosis of P. pachyrhizi and preliminary PCR results were officially confirmed by USDA/APHIS on 18 November 2005. To our knowledge, this is the first report of P. pachyrhizi on kudzu or any host in Kentucky, and currently, the northernmost report of soybean rust on any host in the continental United States. References: (1) P. F. Harmon et al. On-line publication, doi:10.1094/PHP-2005-0613-O1-RS. Plant Health Progress, 2005. (2) R. W. Schneider et al. Plant Dis. 89:774, 2005.

10.
Plant Dis ; 90(3): 380, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30786581

RESUMO

Soybean rust caused by Phakopsora pachyrhizi H. Sydow & Sydow was first reported in the continental United States during 2004 (2). By 10 November 2005, the disease was confirmed in eight southern states (Florida, Georgia, Alabama, Mississippi, South Carolina, North Carolina, Louisiana, and Texas). Diagnoses have been based on visual observation of uredinia and urediniospores of the pathogen followed by polymerase chain reaction confirmation. On 10 November 2005, uredinia and telia were identified on leaves of kudzu (Pueraria lobata) in central Florida. Telia first were noted as dark brown-to-black flecks on the abaxial leaf surface intermingled with abundant tan-to-light brown uredinia. Of 200 leaves examined, 143 (72%) had telia. The number of telia ranged from a few (1/cm2) that were scattered to many (73/cm2). Telia were approximately the same diameter as uredinia, but were appressed to the leaf surface and pigmented. Twenty telia were excised from host tissue with the aid of a dissecting microscope and a 20 gauge hypodermic needle. Telia averaged 89 × 100 µm (n = 20, σ = 17 and 16 µm, respectively). Four telia were crushed and five teliospores from each averaged 4.3 × 8.3 µm (n = 20, σ = 0.5 and 0.9 µm, respectively). Pale yellowish brown-to-hyaline teliospores were similar in color to urediniospores. Observations matched descriptions by Ono et al. (1). To our knowledge, this is the first report of the telial stage of P. pachyrhizi in the United States. References: (1) Y. Ono et al. Mycol. Res. 96:825, 1992. (2) R. W. Schneider et al. Plant Dis. 89:774, 2005.

11.
Ann Thorac Surg ; 71(6): 1825-32, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11426755

RESUMO

BACKGROUND: The aim of this study is to determine the relationships between the cytokines and the inflammatory response in reexpansion pulmonary edema (RPE). METHODS: We examined the cell population, epithelial permeability measured by Evans blue dye (EB), betaglucuronidase and cytokine concentrations in bronchoalveolar lavage fluid (BALF) and/or blood using a rabbit RPE model. RESULTS: We confirmed that RPE is characterized by recruitment of polymorphonuclear leukocytes (PMNs), the release of PMN granular contents into the air spaces, and increased vascular permeability. These findings were highly correlated with increased interleukin-8 (IL-8) and monocyte chemoattractant protein 1 (MCP-1) concentrations in the BALF. Growth related oncogene (GRO) was detected in the BALF from only 2 of the 7 reexpanded lungs while TNFalpha was not detected in any rabbits. A similar but less severe inflammatory response to the reexpanded lung was found in the contralateral lung. CONCLUSIONS: IL-8 and MCP-1 may play important roles in the development of RPE; the inflammatory response is independent of TNFalpha and unilateral reexpansion of the lung induces an inflammatory response not only in the reexpanded lung but also in the contralateral lung.


Assuntos
Quimiocina CCL2/sangue , Interleucina-8/sangue , Atelectasia Pulmonar/imunologia , Edema Pulmonar/imunologia , Síndrome de Resposta Inflamatória Sistêmica/imunologia , Animais , Líquido da Lavagem Broncoalveolar/imunologia , Permeabilidade Capilar/imunologia , Feminino , Pulmão/irrigação sanguínea , Neutrófilos/imunologia , Coelhos
12.
J Cancer Res Clin Oncol ; 126(1): 19-26, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10641745

RESUMO

PURPOSE: The experiments aimed to determine if alpha-chemokine inhibitors are effective suppressors of the growth of adenocarcinomas, a neoplasm with a high mortality rate. METHODS: Expression of growth-related oncogene (GROalpha) and interleukin-8 (IL-8) was determined by enzyme-linked immunosorbent assay. Inhibition of alpha-chemokine binding to tumor cells was assessed in the presence and absence of the hexapeptide, antileukinate. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays were performed to determine the effect of alpha-chemokines, monoclonal antibodies (mAb), and antileukinate on cell proliferation. Finally, antileukinate inhibition of human, lung adenocarcinoma tumor growth, was determined in BALB/c nude mice. RESULTS: All of the adenocarcinomas tested produced either GROalpha or IL-8 or both. Proliferation of lung, stomach and colon adenocarcinoma cells was inhibited by anti-GROalpha mAb and/or anti-IL-8 mAb while recombinant human GROalpha stimulated the proliferation of lung and stomach adenocarcinomas. Antileukinate inhibited GROalpha binding to specific receptors on adenocarcinoma cells and inhibited the proliferation of all adenocarcinomas tested. Colon-derived adenocarcinomas specifically bound IL-8 and this binding was also inhibited by antileukinate. Administration of antileukinate in vivo inhibited the tumor growth of adenocarcinoma A549. CONCLUSIONS: GROalpha and IL-8 are necessary for the growth of lung, stomach and colon adenocarcinomas, and can be inhibited by the hexapeptide, antileukinate. The findings suggest the possibility of using alpha-chemokine receptor inhibitors in the treatment of adenocarcinoma.


Assuntos
Adenocarcinoma/tratamento farmacológico , Quimiocinas CXC/antagonistas & inibidores , Fatores Quimiotáticos/metabolismo , Inibidores do Crescimento/farmacologia , Substâncias de Crescimento/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Proteínas de Neoplasias/farmacologia , Oligopeptídeos/farmacologia , Proto-Oncogenes/efeitos dos fármacos , Adenocarcinoma/metabolismo , Animais , Quimiocina CXCL1 , Quimiocinas CXC/metabolismo , Ensaio de Imunoadsorção Enzimática , Humanos , Interleucina-8/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Células Tumorais Cultivadas
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