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1.
Clin Radiol ; 76(8): 593-598, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33933275

RESUMO

AIM: To evaluate the computed tomography (CT) and magnetic resonance imaging (MRI) features of benign Brenner tumours (BBT) of the ovary. MATERIAL AND METHODS: This was a retrospective two-centre study comprising 35 female patients with a definitive diagnosis of BBT at histology in whom CT and/or MRI examinations had been performed. Two experienced radiologists reviewed the CT and MRI features of 39 ovarian BBT retrospectively with consensus reading. The morphological appearance and size of each tumour were recorded. The presence or absence of calcifications within the solid portion was noted at CT. The reviewed characteristics at MRI included qualitative assessment of the signal intensity of the solid portion on diffusion sequence and contrast enhancement, compared to that of the myometrium. RESULTS: CT and MRI images were available for 27 and 28 lesions, respectively. Sixteen patients had both CT and MRI examinations. BBT were unilateral in 89% of patients, and 49% of lesions were solid and 51% were mixed. Calcifications were depicted at CT in 70.4% of lesions. When present, the cystic portion was multilocular in 85% of cases and corresponded to a mucinous lesion in 74% of cases. Enhancement of the solid portion at MRI was inferior or equal to that of the myometrium in 89% of cases and signal on high b-values diffusion images was deemed low or moderate in 93% of cases. CONCLUSION: The combined CT and MRI findings of a unilateral fibrous ovarian mass containing punctate calcifications often associated with a multilocular cyst suggest the diagnosis of ovarian BBT.


Assuntos
Tumor de Brenner/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neoplasias Ovarianas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Pessoa de Meia-Idade , Ovário/diagnóstico por imagem , Estudos Retrospectivos
2.
Cancer Radiother ; 25(5): 432-440, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33836954

RESUMO

PURPOSE: Stereotactic radiotherapy (SRT) is the standard treatment for brain metastases of non-small-cell lung cancer (NSCLC) and melanoma, mostly in combination with immunotherapy. The objective was to retrospectively evaluate the influence of the time-lapse between immunotherapy and stereotactic radiotherapy on toxicity. PATIENTS AND METHODS: From 2016 to 2019, 59 patients treated with SRT for 103 brain metastases of NSCLC (60%) and melanoma (40%) in combination with concomitant immunotherapy (≤30 days) were included. The prescribed dose was 20Gy/1f or 33Gy/3f at the isocentre and 14Gy or 23.1Gy (70%) respectively at the PTV envelope (PTV=GTV+2mm). The mean tumour diameter was 14mm (4-52mm). The immunotherapies used were anti-PD1 and anti-PDL1. The 103 metastases were classified into 3 groups according to the time-lapse between instatement of immunotherapy and instatement of SRT for the patient concerned: 7 (7%) in group A (≤7 days), 38 (37%) in group B (7 to 14 days) and 58 (56%) in group C (14 to 30 days). RESULTS: The mean follow-up was 10.1 months. The median overall survival was 11.5 months for NSCLC and 12.5 months for melanoma. The percentage of local control (LC) at one year was 65.1% (93.6% for NSCLC and 26.5% for melanoma). The time-lapse between immunotherapy and SRT was not a significant predictor of LC (P=0.86), while the histology was (P<0.001). The proportion of grade≥3 toxicities was 5.1%, and that of radionecrosis was 9.7% (among these patients, 80% were non-symptomatic): 0%, 13.1% and 8.6% for groups A, B and C respectively. The time-lapse between immunotherapy and SRT was not a significant predictor of toxicity. Only tumour volume was a significant predictive factor (P=0.03). CONCLUSION: The time lapse between immunotherapy and SRT does not influence brain toxicity. The tumour volume remains the main factor.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/terapia , Radiocirurgia , Idoso , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/secundário , Carcinoma Pulmonar de Células não Pequenas/terapia , Feminino , Seguimentos , Humanos , Neoplasias Pulmonares/patologia , Masculino , Melanoma/patologia , Melanoma/secundário , Melanoma/terapia , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos Retrospectivos , Neoplasias Cutâneas/patologia , Tempo para o Tratamento , Carga Tumoral
3.
Radiother Oncol ; 154: 227-234, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32976869

RESUMO

BACKGROUND AND PURPOSE: This phase 1 trial aimed to determine the maximum tolerated dose (MTD; primary objective) of a p38-MAPK inhibitor, ralimetinib, with radiotherapy (RT) and chemotherapy (TMZ), in the treatment of newly diagnosed glioblastoma (GBM) patients. MATERIALS AND METHODS: The study was designed as an open-label dose-escalation study driven by a Tite-CRM design and followed by an expansion cohort. Ralimetinib was administered orally every 12 h, 7 days a week, for 2 cycles of 2 weeks at a dose of 100, 200 or 300 mg/12 h. Patients received ralimetinib added to standard concurrent RT (60 Gy in 30 fractions) with TMZ (75 mg/m2/day) and 6 cycles of adjuvant TMZ (150-200 mg/m2 on days 1-5 every 28 days). RESULTS: The MTD of ralimetinib was 100 mg/12 h with chemoradiotherapy. The three patients treated at 200 mg/12 h presented a dose-limiting toxicity: one patient had a grade 3 face edema, and two patients had a grade 3 rash and grade 3 hepatic cytolysis (66%). Of the 18 enrolled patients, 15 received the MTD of ralimetinib. At the MTD, the grade ≥ 3 adverse events during concomitant chemoradiotherapy were hepatic cytolysis (2/15 patients), dermatitis/rash (1/15), lymphopenia (1/15) and nausea/vomiting (1/15). No interaction of TMZ and ralimetinib when administrated concomitantly has been observed. Inhibition of pMAPKAP-K2 (-54%) was observed in peripheral blood mononuclear cells. CONCLUSION: This phase 1 trial is the first trial to study the combination of a p38-MAPK inhibitor, ralimetinib, with radiotherapy (RT) and chemotherapy (TMZ), in the treatment of newly diagnosed glioblastoma (GBM) patients. The MTD of ralimetinib was 100 mg/12 h. The most frequent dose-limiting toxicities were hepatic cytolysis and rash.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Quimiorradioterapia , Dacarbazina/uso terapêutico , Glioblastoma/tratamento farmacológico , Humanos , Imidazóis , Leucócitos Mononucleares , Piridinas , Temozolomida/uso terapêutico
4.
J Pharm Biomed Anal ; 156: 379-388, 2018 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-29783113

RESUMO

Human mistakes are still one of the main reasons of underlying regulatory affairs that in a compliance with FDA's Data Integrity and Analytical Quality by Design (AQbD) must be eliminated. To develop smooth, fast and robust methods that are free of human failures, a state-of-the-art automation was presented. For the scope of this study, a commercial software (DryLab) and a model mixture of 10 drugs were subjected to testing. Following AQbD-principles, the best available working point was selected and conformational experimental runs, i.e. the six worst cases of the conducted robustness calculation, were performed. Simulated results were found to be in excellent agreement with the experimental ones, proving the usefulness and effectiveness of an automated, software-assisted analytical method development.


Assuntos
Fracionamento Químico/métodos , Química Farmacêutica/métodos , Preparações Farmacêuticas/análise , Software , Cromatografia Líquida de Alta Pressão/métodos , Estudos de Viabilidade , Preparações Farmacêuticas/química
5.
Clin Pharmacol Ther ; 102(6): 997-1005, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28445610

RESUMO

Nanoliposomal irinotecan (nal-IRI) is a liposomal formulation of irinotecan with a longer half-life (t1/2 ), higher plasma total irinotecan (tIRI), and lower SN-38 maximum concentration (Cmax ) compared with nonliposomal irinotecan. Population pharmacokinetic (PK) analysis of nal-IRI was performed for tIRI and total SN-38 (tSN38) using patient samples from six studies. PK-safety association was evaluated for neutropenia and diarrhea in 353 patients. PK-efficacy association was evaluated from a phase III study in pancreatic cancer NAPOLI1. Efficacy was associated with longer duration of unencapsulated SN-38 (uSN38) above a threshold and higher Cavg of tIRI, tSN38, and uSN38. Neutropenia was associated with uSN38 Cmax and diarrhea with tIRI Cmax . Baseline predictive factors were race, body surface area, and bilirubin. Analysis identified PK factors associated with efficacy, safety, and predictive baseline factors. The results support the benefit of nal-IRI dose of 70 mg/m2 (free-base; equivalent to 80 mg/m2 salt base) Q2W over 100 mg/m2 Q3W.


Assuntos
Camptotecina/análogos & derivados , Lipossomos/efeitos adversos , Lipossomos/farmacocinética , Neoplasias/metabolismo , Adulto , Idoso , Camptotecina/efeitos adversos , Camptotecina/sangue , Camptotecina/farmacocinética , Ensaios Clínicos como Assunto , Diarreia/induzido quimicamente , Feminino , Humanos , Irinotecano , Lipossomos/sangue , Masculino , Pessoa de Meia-Idade , Neoplasias/sangue , Neoplasias/tratamento farmacológico , Neutropenia/induzido quimicamente
6.
Klin Khir ; (10): 70-2, 2015 Oct.
Artigo em Ucraniano | MEDLINE | ID: mdl-26946668

RESUMO

Morphological changes in gastric mucosa were studied, optimal terms of bariatric operations performance after intragastric balloon (IGB) insertion were determined. Before the IGB insertion in 10 (35.7%) patients, in accordance to histological investigations, the changes in gastric mucosa were not revealed, and in 18 (64.3%) - chronic gastritis was established. In accordance to endoscopic investigation results, immediately after the IGB removal in 23 (82.1%) patients a pronounced erythematous gastropathy was noted, and in 5 (17.9%) - erosive gastropathy. While investigating the gastric mucosa biopsies in all the patients a prominent inflammatory changes were revealed, including significant edema, pronounced lymphocytic infiltration. In accordance to esophagogastroduodenoscopy data on the 14-th day of endoscopic monitoring in 6 (21.4%) patients pathological changes of gastric mucosa were not revealed, in 22 (78.6 %) - erythematous gastropathy was noted, and in accordance to histological investigation - chronic gastritis. Persistence of IGB in gastric cavity during 6 mo caused a morphological changes in gastric mucosa - a significant inflammation, what was confirmed by endoscopic and histological investigations data. The gastric mucosa structure normalization was observed in 14 days after the IGB removal, that's why a radical bariatric intervention is recommended to perform not earlier the term established.


Assuntos
Cirurgia Bariátrica , Balão Gástrico , Mucosa Gástrica/cirurgia , Gastrite/cirurgia , Obesidade Mórbida/cirurgia , Biópsia , Feminino , Mucosa Gástrica/patologia , Gastrite/patologia , Gastroscopia , Histocitoquímica , Humanos , Masculino , Obesidade Mórbida/patologia
7.
Commun Agric Appl Biol Sci ; 80(2): 149-52, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27145579

RESUMO

The increasing pressure of oilseed rape pests emphasized the need to improve the insecticide portfolio, i.e. register new active ingredients with new insecticide mode of action. The tested seed treatment formulation applied at 32; 40 and 50 UAT rate of containing cyantraniliprole as active substance. 40 UAT rate gives acceptable control of the Cabbage root fly in each trial. Despite the long lasting flight and egg laying period of cabbage root fly, the standard control products and also this product give 50-65% efficacy. It is enough to reduce damage of the Cabbage root fly and prevent economical damage in oilseed rape.


Assuntos
Brassica napus , Dípteros , Controle de Insetos , Inseticidas , Pirazóis , ortoaminobenzoatos , Animais , Brassica napus/crescimento & desenvolvimento , Besouros/crescimento & desenvolvimento , Dípteros/crescimento & desenvolvimento , Larva , Pupa , Estações do Ano , Sementes
9.
Osteoporos Int ; 25(2): 783-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24337660

RESUMO

UNLABELLED: The role of proinflammatory IL-17 cytokine was studied in postmenopausal bone loss between 31 osteopenic and 41 osteoporotic women. The effect of serum IL-17A, soluble receptor activator of NF-κB (sRANK) ligand, and osteoprotegerin (OPG) levels on lumbar bone mineral densities was measured. The results demonstrated an increased IL-17A-mediated sRANK ligand elevation in postmenopausal osteoporotic bone loss. INTRODUCTION: IL-17 proinflammatory cytokine is a new inducer of bone loss. Postmenopausal osteoporosis represents a cross talk between estrogen deprivation and increased immune reactivity. The role of IL-17 was studied in the bone loss of postmenopausal osteoporosis. METHODS: Serum IL-17A, sRANK ligand, and OPG levels were investigated on bone mineral densities (BMDs) in the total lumbar (L1-L4) region in 18 pre- and 72 postmenopausal women. IL-17A, sRANK ligand, OPG levels, and BMDs were measured with enzyme-linked immunosorbent assay (ELISA) and dual-energy X-ray absorptiometry (DXA). RESULTS: Increased serum IL-17A, sRANK ligand, and OPG levels were demonstrated in postmenopausal osteoporotic women compared to osteopenic women (3.65 ± 0.61 vs 3.31 ± 0.43 ng/ml for IL-17A, P < 0.007; 2.88 ± 0.84 vs 2.49 ± 0.61 ng/ml for sRANK ligand, P < 0.027; and 1.43 ± 0.07 vs 1.39 ± 0.07 ng/ml for OPG, P < 0.038). In postmenopausal women, IL-17A levels correlated inversely with total lumbar BMDs (P < 0.008, r = -0.279) and positively with sRANK ligand levels (P < 0.0001, r = 0.387) or the ratio of sRANK ligand and OPG (P < 0.013, r = 0.261), but did not with OPG levels alone. CONCLUSION: Increased IL-17A levels are involved in postmenopausal osteoporosis, playing a role in the bone-resorpting processes.


Assuntos
Interleucina-17/fisiologia , Osteoporose Pós-Menopausa/sangue , Ligante RANK/sangue , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Doenças Ósseas Metabólicas/sangue , Doenças Ósseas Metabólicas/fisiopatologia , Feminino , Humanos , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/fisiopatologia , Osteoprotegerina/sangue , Pré-Menopausa/fisiologia
10.
Br J Cancer ; 108(2): 311-8, 2013 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-23322192

RESUMO

BACKGROUND: Elderly patients tend to be underrepresented in renal cell carcinoma (RCC) clinical trials. The Sorafenib RCC Integrated Database includes data from six clinical trials and two expanded-access studies evaluating sorafenib monotherapy in >4600 patients with RCC. Using this database, sorafenib tolerability and treatment patterns were analysed according to age group (<55, 55-<65, 65-<75, or ≥ 75 years). METHODS: Dosing patterns, and incidence, prevalence and cumulative incidence of drug-related adverse events (DRAEs) and fatal DRAEs were assessed. RESULTS: Overall, 4684 patients were evaluable (<55 years, n=1126; 55-<65, n=1579; 65-<75, n=1382; ≥ 75, n=559). Treatment patterns were generally similar across subgroups, although sorafenib treatment duration was ∼30% shorter in the ≥ 75-years subgroup. There were no substantial differences in any-grade DRAEs with sorafenib between subgroups. Drug-related adverse events and dose modifications due to DRAEs tended to occur in months 0-3 and declined thereafter; there was no evidence of cumulative toxicity. Fatal DRAEs were rare (0.7% overall; 95% confidence interval, 0.5-1.0%). CONCLUSION: Sorafenib was well tolerated regardless of age in a heterogeneous population of RCC patients.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/mortalidade , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/mortalidade , Niacinamida/análogos & derivados , Compostos de Fenilureia , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Niacinamida/administração & dosagem , Niacinamida/efeitos adversos , Niacinamida/uso terapêutico , Compostos de Fenilureia/administração & dosagem , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/uso terapêutico , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Sorafenibe , Resultado do Tratamento
11.
Cytogenet Genome Res ; 139(2): 128-36, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23306424

RESUMO

Chromosome pairing in the meiotic metaphase I of wheat-rye hybrids has been characterized by sequential genomic and fluorescent in situ hybridization allowing not only the discrimination of wheat and rye chromosomes, but also the identification of the individual wheat and rye chromosome arms involved in the chromosome associations. The majority of associations (93.8%) were observed between the wheat chromosomes. The largest number of wheat-wheat chromosome associations (53%) was detected between the A and D genomes, while the frequency of B-D and A-B associations was significantly lower (32 and 8%, respectively). Among the A-D chromosome associations, pairing between the 3AL and 3DL arms was observed with the highest frequency, while the most frequent of all the chromosome associations (0.113/cell) was found to be the 3DS-3BS. Differences in the pairing frequency of the individual chromosome arms of wheat-rye hybrids have been discussed in relation to the homoeologous relationships between the constituent genomes of hexaploid wheat.


Assuntos
Cromossomos de Plantas/genética , Análise Citogenética/métodos , Secale/genética , Triticum/genética , Pareamento Cromossômico/genética , Genoma de Planta/genética , Hibridização Genética , Hibridização in Situ Fluorescente/métodos , Meiose/genética , Pólen/citologia , Pólen/metabolismo , Reprodutibilidade dos Testes , Especificidade da Espécie
12.
J Chromatogr A ; 1232: 218-30, 2012 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-22226460

RESUMO

Robust HPLC separations lead to fewer analysis failures and better method transfer as well as providing an assurance of quality. This work presents the systematic development of an optimal, robust, fast UHPLC method for the simultaneous assay of two APIs of an eye drop sample and their impurities, in accordance with Quality by Design principles. Chromatography software is employed to effectively generate design spaces (Method Operable Design Regions), which are subsequently employed to determine the final method conditions and to evaluate robustness prior to validation.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida de Alta Pressão/normas , Projetos de Pesquisa/normas , Software , Modelos Teóricos , Reprodutibilidade dos Testes , Interface Usuário-Computador
13.
J Pharm Biomed Anal ; 56(5): 874-9, 2011 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-21893394

RESUMO

The current article presents a novel approach to applying Quality by Design (QbD) principles to the development of high pressure reversed phase liquid chromatography (HPLC) methods. Four common critical parameters in HPLC--gradient time, temperature, pH of the aqueous eluent, and stationary phase--are evaluated within the Quality by Design framework by the means of computer modeling software and a column database, to a satisfactory degree. This work proposes the establishment of two mutually complimentary Design Spaces to fully depict a chromatographic method; one Column Design Space (CDS) and one Eluent Design Space (EDS) to describe the influence of the stationary phase and of the mobile phase on the separation selectivity, respectively. The merge of both Design Spaces into one is founded on the continuous nature of the mobile phase influence on retention and the great variety of the stationary phases available.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Concentração de Íons de Hidrogênio , Modelos Teóricos
14.
Genome ; 54(10): 795-804, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21919737

RESUMO

A spontaneous interspecific Robertsonian translocation was revealed by genomic in situ hybridization (GISH) in the progenies of a monosomic 7H addition line originating from a new wheat 'Asakaze komugi' × barley 'Manas' hybrid. Fluorescence in situ hybridization (FISH) with repetitive DNA sequences (Afa family, pSc119.2, and pTa71) allowed identification of all wheat chromosomes, including wheat chromosome arm 4BS involved in the translocation. FISH using barley telomere- and centromere-specific repetitive DNA probes (HvT01 and (AGGGAG)(n)) confirmed that one of the arms of barley chromosome 7H was involved in the translocation. Simple sequence repeat (SSR) markers specific to the long (L) and short (S) arms of barley chromosome 7H identified the translocated chromosome segment as 7HL. Further analysis of the translocation chromosome clarified the physical position of genetically mapped SSRs within 7H, with a special focus on its centromeric region. The presence of the HvCslF6 gene, responsible for (1,3;1,4)-ß-D-glucan production, was revealed in the centromeric region of 7HL. An increased (1,3;1,4)-ß-D-glucan level was also detected in the translocation line, demonstrating that the HvCslF6 gene is of potential relevance for the manipulation of wheat (1,3;1,4)-ß-D-glucan levels.


Assuntos
Marcadores Genéticos , Hordeum/genética , Repetições de Microssatélites , Proteínas de Plantas/genética , Triticum/genética , beta-Glucanas/análise , Quimera , Cromossomos de Plantas , Genoma de Planta , Hibridização in Situ Fluorescente , Translocação Genética , Triticum/química
15.
J Chromatogr A ; 1217(19): 3193-200, 2010 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-20189187

RESUMO

The present paper describes a multifactorial optimization of 4 critical HPLC method parameters, i.e. gradient time (t(G)), temperature (T), pH and ternary composition (B(1):B(2)) based on 36 experiments. The effect of these experimental variables on critical resolution and selectivity was carried out in such a way as to systematically vary all four factors simultaneously. The basic element is a gradient time-temperature (t(G)-T) plane, which is repeated at three different pH's of the eluent A and at three different ternary compositions of eluent B between methanol and acetonitrile. The so-defined volume enables the investigation of the critical resolution for a part of the Design Space of a given sample. Further improvement of the analysis time, with conservation of the previously optimized selectivity, was possible by reducing the gradient time and increasing the flow rate. Multidimensional robust regions were successfully defined and graphically depicted.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Acetonitrilas/química , Simulação por Computador , Concentração de Íons de Hidrogênio , Metanol/química , Modelos Teóricos , Reprodutibilidade dos Testes , Projetos de Pesquisa , Temperatura , Fatores de Tempo , Interface Usuário-Computador
16.
Genome ; 52(9): 748-54, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19935922

RESUMO

The absence of chromosome 7D in the wheat-Thinopyrum ponticum partial amphiploid BE-1 was detected previously by multicolour genomic in situ hybridization, sequential FISH (fluorescence in situ hybridization) using repetitive DNA probes, and SSR marker analysis. In the present study the previous cytogenetic and SSR marker analyses were expanded to include 25 other SSR markers assigned to wheat chromosomes 7A and 7D to confirm the presence of a 7A.7D translocation and to specify its composition. An almost complete chromosome 7A and a short chromosome segment derived from the terminal region of 7DL were detected, confirming the presence of a terminal translocation involving the distal regions of 7AL and 7DL. In both cases the position of the translocation breakpoint was different from that of known deletion lines. The identification of the 7AL.7DL translocation and its breakpoint position provides a new physical landmark for future physical mapping studies, opening up the possibility of more precise localization of genes or molecular markers within the terminal regions of 7DL and 7AL.


Assuntos
Coloração Cromossômica/métodos , Cromossomos de Plantas/genética , Repetições de Microssatélites/genética , Mapeamento Físico do Cromossomo/métodos , Sondas de DNA/genética , DNA de Plantas/genética , Diploide , Genoma de Planta , Hibridização Genética , Reação em Cadeia da Polimerase , Translocação Genética
17.
Theor Appl Genet ; 116(6): 825-34, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18224300

RESUMO

In situ hybridization (multicolor GISH and FISH) was used to characterize the genomic composition of the wheat-Thinopyrum ponticum partial amphiploid BE-1. The amphiploid is a high-protein line having resistance to leaf rust (Puccinia recondita f. sp. tritici) and powdery mildew (Blumeria graminis f. sp. tritici) and has in total 56 chromosomes per cell. Multicolor GISH using J, A and D genomic probes showed 16 chromosomes originating from Thinopyrum ponticum and 14 A genome, 14 B genome and 12 D genome chromosomes. Six of the Th. ponticum chromosomes carried segments different from the J genome in their centromeric regions. It was demonstrated that these alien chromosome segments did not originate from the A, B or D genomes of wheat, so the translocation chromosomes were considered to be J(s) type chromosomes carrying segments similar to the S genome near the centromeres. Rearrangements between the A and D genomes of wheat were detected. FISH using Afa family, pSc119.2 and pTa71 probes allowed the identification of all the wheat chromosomes present and the determination of the chromosomes involved in the translocations. The 4A and 7A chromosomes were identified as being involved in intergenomic translocations. The replaced wheat chromosome was identified as 7D. The localization of these repetitive DNA clones on the Th. ponticum chromosomes of the amphiploid was described in the present study. On the basis of their multicolor FISH patterns, the alien chromosomes could be arranged in eight pairs and could also be differentiated unequivocally from each other.


Assuntos
Cromossomos de Plantas/genética , Genes de Plantas , Hibridização in Situ Fluorescente , Triticum/genética , Triticum/microbiologia , Sondas de DNA , Cariotipagem , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Triticum/metabolismo
20.
Biochem Soc Trans ; 34(Pt 6): 1236-40, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17073793

RESUMO

4''-Oxo-avermectin is a key intermediate in the manufacture of the insecticide emamectin benzoate from the natural product avermectin. Seventeen Streptomyces strains with the ability to oxidize avermectin to 4''-oxo-avermectin in a regioselective manner have been discovered, and the enzymes responsible for this reaction were found to be CYPs (cytochrome P450 mono-oxygenases). The genes for these enzymes have been cloned, sequenced and compared to reveal a new subfamily of CYPs. The biocatalytic enzymes have been overexpressed in Escherichia coli, Streptomyces lividans and solvent-tolerant Pseudomonas putida strains using different promoters and vectors. FDs (ferredoxins) and FREs (ferredoxin:NADP(+) reductases) were also cloned from Streptomyces coelicolor and biocatalytic Streptomyces strains, and tested in co-expression systems to optimize the electron transport. Subsequent studies showed that increasing the biocatalytic conversion levels to commercial relevance results in the production of several side products in significant amounts. Chimaeric Ema CYPs were created by sequential rounds of GeneReassembly, a proprietary directed evolution method, and selected for improved substrate specificity by high-throughput screening.


Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Ivermectina/análogos & derivados , Biotransformação , Catálise , Sistema Enzimático do Citocromo P-450/genética , Transporte de Elétrons , Ivermectina/metabolismo , Cinética , Solventes
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