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1.
Cryo Letters ; 44(3): 123-133, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37883165

RESUMO

Several clinical trials have proved the efficacy and safety of T-cells chimeric antigen receptor (CAR-T cells) in treatment of malignant lymphoma and the first products were registered in the European Union in 2018. The shelf-life of CAR-T cell products in the liquid state is short, so cryopreservation offers a significant benefit for logistics in manufacturing and patient management. Direct shipment of the cryopreserved CAR-T cell therapy products to the clinical department is feasible, nevertheless, intermediate storage in the hospital cryostorage facility gives significant advantage in planning of their administration to patients. Moreover, some manufacturers prefer transport of the starting material cryopreserved at the collection site. The cryopreservation protocol used for starting material by the authors is based on combining dimethyl sulphoxide (DMSO) with hydroxyethyl starch (HES) and slow controlled cooling in cryobags housed in metal cassettes. This achieves the mononuclear cell post-thaw viability of 98.8 ± 0.5 % and recovery of 72.8, ± 10.2 %. Transport of the starting material to the manufactures and return transport of the CAR-T therapy product is performed by authorized courier companies. Intermediate cryostorage of the final CAR-T cell therapy product is performed in a separate dry-storage liquid nitrogen container. On the day of infusion, the cryopreserved products are transported to the clinical department in a dry shipper. On the wards the product is removed from the cassette, inserted into a sterile plastic bag, thawed in a 37 degree C water bath followed by immediate intravenous administration. The authors discuss the adherence of the used technology to good manufacturing practice (GMP) principles and genetic safety assurance rules. Doi: 10.54680/fr23310110112.


Assuntos
Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/genética , Criopreservação/métodos , Imunoterapia Adotiva/métodos , Temperatura Baixa
2.
Br J Cancer ; 111(6): 1021-46, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25117809

RESUMO

Cell-line misidentification and contamination with microorganisms, such as mycoplasma, together with instability, both genetic and phenotypic, are among the problems that continue to affect cell culture. Many of these problems are avoidable with the necessary foresight, and these Guidelines have been prepared to provide those new to the field and others engaged in teaching and instruction with the information necessary to increase their awareness of the problems and to enable them to deal with them effectively. The Guidelines cover areas such as development, acquisition, authentication, cryopreservation, transfer of cell lines between laboratories, microbial contamination, characterisation, instability and misidentification. Advice is also given on complying with current legal and ethical requirements when deriving cell lines from human and animal tissues, the selection and maintenance of equipment and how to deal with problems that may arise.


Assuntos
Pesquisa Biomédica/normas , Linhagem Celular/microbiologia , Equipamentos e Provisões/normas , Mycoplasma , Segurança/normas , Animais , Pesquisa Biomédica/ética , Linhagem Celular/classificação , Criopreservação/normas , Meios de Cultura/normas , Contaminação de Equipamentos/prevenção & controle , Instabilidade Genômica , Humanos , Mycoplasma/isolamento & purificação , Fenótipo , Controle de Qualidade , Manejo de Espécimes/métodos , Manejo de Espécimes/normas , Reino Unido
3.
J Youth Adolesc ; 41(9): 1184-96, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22752878

RESUMO

Despite the known deficits in sleep that occur during adolescence and the high prevalence of substance use behaviors among this group, relatively little research has explored how sleep and substance use may be causally related. The purpose of this study was to explore the longitudinal bi-directional relationships between sleep duration, sleep patterns and youth substance use behaviors. Participants included 704 mostly white (86.4 %) youth, 51 % female, with a baseline mean age of 14.7 years. Self-reported substance use behaviors included past month alcohol, cigarette, and marijuana use. Sleep measures included sleep duration on weekends and weekdays, total sleep, weekend oversleep, and weekend sleep delay. Cross-lagged structural equation models, accounting for clustering at the school level, were run to determine the longitudinal association between sleep and substance use adjusting for socio-demographic characteristics, pubertal status, body mass index z-score, and depressive symptoms. Cigarette use and weekend sleep were bi-directionally related as were marijuana use and total sleep. No other bi-directional associations were identified. However, alcohol use predicted shorter weekend oversleep and marijuana use predicted increased weekend sleep and weekend oversleep. Sleep patterns and duration also predicted adolescents' cigarette, alcohol, and marijuana use. Sleep, both patterns and duration, and substance use among youth are intertwined. Future research is needed to explore these bi-directional relationships, as well as other important contextual factors that may moderate these associations.


Assuntos
Comportamento do Adolescente/psicologia , Assunção de Riscos , Privação do Sono/epidemiologia , Transtornos do Sono-Vigília/epidemiologia , Vigília , Adolescente , Ritmo Circadiano , Comorbidade , Feminino , Humanos , Estudos Longitudinais , Masculino , Fatores de Risco , Privação do Sono/psicologia , Transtornos do Sono-Vigília/psicologia
4.
J Youth Adolesc ; 41(1): 14-26, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21853355

RESUMO

Both substance use and obesity are prevalent among youth. As youth age, substance use rates increase and over the past three decades, obesity rates among youth have tripled. While these two factors have both short- and long-term health impacts, little research has explored how substance use and obesity among youth may be related. This study explores the bi-directional longitudinal relationships between substance use and body composition. Participants (N = 704; 50.7% female) were mostly white (86.4%) with a baseline mean age of 14.7 years. Objectively measured body composition was used to calculate body mass index z-scores (BMI z-score) and percent body fat. Cross-lagged structural equation models, accounting for clustering at the school level, were run to determine the longitudinal association between body composition and self-reported substance use (alcohol, cigarette, and marijuana), adjusting for socio-demographic characteristics, pubertal status, and weight satisfaction. Baseline alcohol use predicted decreased BMI z-score at follow-up and a similar association with percent body fat approached significance. Baseline cigarette use predicted increased percent body fat. No longitudinal associations were seen between baseline body composition and future substance use. Our results suggest that substance use contributes to subsequent body composition; however, body composition does not contribute to subsequent substance use. Continued research that explores these relationships longitudinally is greatly needed.


Assuntos
Obesidade/complicações , Transtornos Relacionados ao Uso de Substâncias/complicações , Tecido Adiposo , Adolescente , Índice de Massa Corporal , Feminino , Inquéritos Epidemiológicos , Humanos , Estudos Longitudinais , Masculino , Modelos Estatísticos , Fatores de Risco , Autorrelato , Fatores Socioeconômicos
5.
J Adolesc Health ; 43(4): 387-93, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18809137

RESUMO

PURPOSE: To examine cross-sectional and longitudinal associations between weight status and measures of risk and protective factors in youth. METHODS: Participants included 3010 students (72.1% white, 27.9% nonwhite), with a baseline mean age of 12.7 years from the Teens Eating for Energy and Nutrition at School (TEENS) study. Surveys were administered in grades 7 and 8. Cross-sectional and longitudinal mixed-effects regression analyses were conducted to determine the association between body mass index z-score percentiles (BMI) and risk and protective factors (including substance use, depression, fighting, optimism, and spirituality). RESULTS: Only depression was associated with BMI at the beginning of grade 7. However, by the end of grade 8, binge drinking, alcohol, tobacco, and other drug (ATOD) use, fighting, and depression were all cross-sectionally associated with BMI. Longitudinally, BMI in grade 7 did not predict risk and protective factors in grade 8. However, ATOD use, fighting, depression, and optimism in grade 7 predicted BMI in grade 8. CONCLUSIONS: This study suggests there is a notable co-occurrence of unhealthy factors (including weight status, ATOD use, depression) which appears to develop during the critical transition period through early adolescence. Specifically, earlier ATOD use, depression, increased fighting, and decreased optimism may lead to unhealthy increases in weight status, whereas early indicators of increased weight status do not appear to predict increases in these factors. This work yields important insights into the causal mechanisms underlying adolescent behavior patterning and the progression with which these unhealthy risk factor profiles are adopted during this critical age.


Assuntos
Comportamento do Adolescente , Índice de Massa Corporal , Comportamentos Relacionados com a Saúde , Assunção de Riscos , Adolescente , Criança , Estudos Transversais , Depressão/etiologia , Humanos , Estudos Longitudinais , Análise de Regressão , Comportamento de Redução do Risco , Espiritualidade , Aumento de Peso
6.
Clin Nucl Med ; 31(11): 704-6, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17053390

RESUMO

A 27-year-old white man was diagnosed with a testicular, metastatic germ cell tumor. The patient was evaluated with F-18 fluorodeoxyglucose positron emission tomography and coregistered computed tomography (FDG PET/CT) as well as a contrast-enhanced CT (CECT) of the abdomen and pelvis. Serologic tests were performed. At laparoscopic appendectomy, findings were consistent with acute suppurative appendicitis. This case exemplifies the relevance of incidental findings detected on FDG PET/CT.


Assuntos
Apendicite/diagnóstico , Fluordesoxiglucose F18 , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Humanos , Achados Incidentais , Masculino , Compostos Radiofarmacêuticos , Técnica de Subtração , Neoplasias Testiculares/diagnóstico
7.
BJU Int ; 98(3): 540-3, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16925750

RESUMO

OBJECTIVE: To evaluate ultrasensitive (US) measurements of prostate-specific antigen (PSA) level in men with prostate cancer, and to correlate the findings with currently accepted values for PSA recurrence, as PSA is widely accepted as a surrogate marker for disease recurrence after treatment for prostate cancer, and although USPSA assays can detect minute quantities of PSA, the significance of this is unclear. PATIENTS AND METHODS: In all, 225 patients had a radical prostatectomy (RP) and were followed with USPSA measurements. PSA recurrence was defined as two or more consecutive increasing PSA values after RP of > or = 0.200 ng/mL. This was deemed clinically significant if it was associated with adjuvant treatment with a repeated nadir PSA level, or a PSA level that continued to increase on watchful waiting. USPSA values were compared between patients who recurred and those who did not, to determine any association with PSA recurrence and clinical outcomes. RESULTS: There was a PSA recurrence in 21 patients; all had clinical evidence of recurrence. Although the difference in mean USPSA levels was statistically significant for those patients who did and did not recur, the overlap in values invalidated any clinical utility. However, an undetectable level achieved during the follow-up appeared to confer a favourable prognosis. CONCLUSION: After RP patients might have PSA levels detectable by USPSA assays, i.e. <0.1 ng/mL. The amount of 'background noise' produced within this range precludes the ability to use this test as a clinical indicator of disease recurrence. However, undetectable levels appear to confer a favourable prognosis.


Assuntos
Antígeno Prostático Específico/metabolismo , Prostatectomia/métodos , Neoplasias da Próstata/sangue , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Neoplasias da Próstata/cirurgia , Sensibilidade e Especificidade
8.
Appl Microbiol Biotechnol ; 72(2): 279-90, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16447052

RESUMO

The productivity of stable Chinese hamster ovary cell lines secreting HIV-1 monomeric (IIIB gp120) and oligomeric (UG21 gp140) recombinant envelope glycoproteins was compared in serum-containing (S+), serum-free (S-) and protein-free (P-) culture media. UG21 gp140 expression was greatest in S+ medium, while IIIBgp120 production was lower than gp140 in all three media but highest in S-. UG21 gp140 production was highest in standard 850-cm2 roller bottle cultures in S+ media, peaking after 14 days of incubation, while expression levels in the three media were 0.5 (S+), 0.4 (S-) and 0.2 (P-) mg/l, from which 90, 80 and 12% of gp140, respectively, could be purified by immunoaffinity chromatography. Purified UG21 gp140 from S+ and S- media possessed biological functionality as evidenced by CD4 and monoclonal antibody (Mab) binding. In contrast, UG21 gp140 from P- medium appears to be misfolded and non-functional. Despite the possession of a different N-linked glycan profile, UG21 gp140 from S- media shows very similar CD4 and Mab binding characteristics to S+ UG21 gp140. The relevance of these findings to HIV vaccine development is discussed.


Assuntos
Meios de Cultura/química , Produtos do Gene env/biossíntese , Proteína gp120 do Envelope de HIV/biossíntese , HIV-1/metabolismo , Animais , Antígenos CD4/metabolismo , Células CHO , Técnicas de Cultura de Células/instrumentação , Técnicas de Cultura de Células/métodos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Cricetinae , Cricetulus , Meios de Cultura/farmacologia , Produtos do Gene env/genética , Produtos do Gene env/metabolismo , Proteína gp120 do Envelope de HIV/genética , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1/genética , Polissacarídeos/análise , Ligação Proteica , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Produtos do Gene env do Vírus da Imunodeficiência Humana
9.
Mol Genet Genomics ; 270(4): 347-61, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14598165

RESUMO

Apyrases have been suggested to play important roles in plant nutrition, photomorphogenesis, and nodulation. To help trace the evolution of these genes in the legumes--and possibly, the acquisition of new functions for nodulation--apyrase-containing BACs were sequenced from three legume genomes. Genomic sequences from Medicago truncatula, Glycine max and Lotus japonicus were compared to one another and to corresponding regions in Arabidopsis thaliana. A phylogenetic analysis of apyrase homologs from these regions and sequences from other legume species, as well as other plant families, identified a potentially legume-specific clade that contains a well-characterized soybean ( G. soja) apyrase, Gs52, as well as homologs from Dolichos, Lotus, Medicago and Pisum. Sister clades contain homologs from members of Brassicaceae, Solanaceae, Poaceae and Fabaceae. Comparisons of rates of change at synonymous and nonsynonymous sites in the Gs52 and sister clades show rapid evolution in the potentially legume-specific Gs52 clade. The genomic organization of the apyrase-containing BACs shows evidence of gene duplication, genomic rearrangement, and gene conversion among Gs52 homologs. Taken together, these results suggest a scenario of local apyrase gene duplication in an ancestor of the legumes, followed by functional diversification and increased rates of change in the new genes, and further duplications in the Galegae (which include the genera Medicago and Pisum). The study also provides a detailed comparison of genomic regions between two model genomes which are now being sequenced ( M. truncatulaand L. japonicus), and a genome from an economically important legume species ( G. max).


Assuntos
Apirase/genética , Evolução Molecular , Fabaceae/genética , Sintenia , Cromossomos Artificiais Bacterianos , Fabaceae/enzimologia , Duplicação Gênica , Variação Genética , Genoma , Modelos Genéticos , Filogenia , Homologia de Sequência
10.
Amino Acids ; 21(2): 185-94, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11665814

RESUMO

The toxicity of new surfactants containing a beta-lactam ring has been established by studying their interaction with a hybridoma cell line. An hour of contact is sufficient to generate an apoptotic signal after two days of culture. Under the experimental conditions chosen for the experiments, surfactants have been divided into three categories: i) biocompatible and non-apogenic; ii) surfactants triggering an apoptotic signal without inducing cell necrosis; iii) surfactants triggering an apoptotic signal at low concentrations and destroying the cells by necrosis at higher concentrations. The necrosis inducing surfactants also had haemolytic properties. These properties were related to the values of the hydrophilic-lipophilic balance of the molecules.


Assuntos
Apoptose , Detergentes/toxicidade , Eritrócitos/efeitos dos fármacos , Tensoativos/toxicidade , beta-Lactamas/química , Animais , Sobrevivência Celular , Detergentes/química , Hemólise/efeitos dos fármacos , Humanos , Camundongos , Estrutura Molecular , Tensoativos/química , Testes de Toxicidade , Células Tumorais Cultivadas , beta-Lactamas/análise
11.
Plant Physiol ; 125(4): 2104-19, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11299390

RESUMO

Four putative apyrase genes were identified from the model legume Medicago truncatula. Two of the genes identified from M. truncatula (Mtapy1 and Mtapy4) are expressed in roots and are inducible within 3 h after inoculation with Sinorhizobium meliloti. The level of mRNA expression of the other two putative apyrases, Mtapy2 and Mtapy3, was unaffected by rhizobial inoculation. Screening of a bacterial artificial chromosome library of M. truncatula genomic DNA showed that Mtapy1, Mtapy3, and Mtapy4 are present on a single bacterial artificial chromosome clone. This apyrase cluster was mapped to linkage group seven. A syntenic region on soybean linkage group J was found to contain at least two apyrase genes. Screening of nodulation deficient mutants of M. truncatula revealed that two such mutants do not express apyrases to any detectable level. The data suggest a role for apyrases early in the nodulation response before the involvement of root cortical cell division leading to the nodule structure.


Assuntos
Apirase/genética , Regulação da Expressão Gênica de Plantas , Medicago sativa/enzimologia , Medicago sativa/genética , Sinorhizobium/fisiologia , Transcrição Gênica , Sequência de Aminoácidos , Apirase/biossíntese , Apirase/química , Sequência Conservada , Indução Enzimática , Regulação Enzimológica da Expressão Gênica , Humanos , Isoenzimas/biossíntese , Isoenzimas/química , Isoenzimas/genética , Medicago sativa/microbiologia , Dados de Sequência Molecular , Raízes de Plantas/enzimologia , Plantas/enzimologia , Plantas/genética , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Fatores de Tempo
12.
Mol Plant Microbe Interact ; 13(10): 1053-70, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11043467

RESUMO

Two cDNA clones were isolated from soybean (Glycine soja) by polymerase chain reaction with primers designed to conserved motifs found in apyrases (nucleotide phosphohydrolase). The two cDNAs are predicted to encode for two, distinct, apyrase proteins of approximately 50 kDa (i.e., GS50) and 52 kDa (i.e., GS52). Phylogenetic analysis indicated that GS52 is orthologous to a family of apyrases recently suggested to play a role in legume nodulation. GS50 is paralogous to this family and, therefore, likely plays a different physiological role. Consistent with this analysis, GS50 mRNA was detected in root, hypocotyls, flowers, and stems, while GS52 mRNA was found in root and flowers. Neither gene was expressed in leaves or cotyledons. Inoculation of roots with Bradyrhizobium japonicum, nitrogen-fixing symbiont of soybean, resulted in the rapid (<6 h) induction of GS52 mRNA expression. The level of GS50 mRNA expression was not affected by bacterial inoculation. Western blot (immunoblot) analysis of GS50 expression mirrored the results obtained by mRNA analysis. However, in contrast to the mRNA results, GS52 protein was found in stems. Interestingly, anti-GS52 antibody recognized a 50-kDa protein found only in nodule extracts. Treatment of roots with anti-GS52 antibody, but not anti-GS50 antibody or preimmune serum, blocked nodulation by B. japonicum. Fractionation of cellular membranes in sucrose density gradients and subsequent Western analysis of the fractions revealed that GS50 colocalized with marker enzymes for the Golgi, while GS52 colocalized with marker enzymes for the plasma membrane. Restriction fragment length polymorphism (RFLP)-based mapping placed the gs52 gene on major linkage group J of the integrated genetic map of soybean. These data suggest that GS50 is likely an endo-apyrase involved in Golgi function, while GS52 is localized on the root surface and appears to play an important role in nodulation.


Assuntos
Apirase/genética , Glycine max/enzimologia , Proteínas de Membrana , Proteínas de Plantas/genética , Sequência de Aminoácidos , Anticorpos/imunologia , Apirase/imunologia , Apirase/isolamento & purificação , Apirase/metabolismo , Bradyrhizobium/fisiologia , Mapeamento Cromossômico , Primers do DNA , DNA Complementar , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Proteínas de Plantas/metabolismo , Raízes de Plantas/enzimologia , Raízes de Plantas/microbiologia , Estruturas Vegetais/enzimologia , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/isolamento & purificação , Glycine max/genética , Glycine max/microbiologia , Glycine max/fisiologia
13.
FEMS Microbiol Lett ; 190(1): 109-14, 2000 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-10981699

RESUMO

A 3.0-kb region involved in lipopolysaccharide biosynthesis in Bradyrhizobium japonicum was sequenced. One complete open reading frame was identified which encodes a polypeptide of 354 amino acid residues with a predicted molecular mass of 38 209 Da. Expression of the protein using a T7 gene expression system revealed a band of similar molecular mass after sodium dodecyl sulfate polyacrylamide gel electrophoresis. A database search against known gene sequences revealed a significant sequence similarity to the rfaF gene cloned from several Gram-negative bacteria. The rfaF gene is known to encode heptosyltransferase II that transfers a second heptose to the inner core of lipopolysaccharide. The cloned B. japonicum open reading frame was able to functionally complement a rfaF mutant of Salmonella typhimurium SL3789. Transformation of this mutant with the B. japonicum gene restored production of an intact lipopolysaccharide and resistance to the hydrophobic antibiotic, novobiocin. An additional open reading frame having a significant sequence similarity to the rfaD gene was found to be divergently oriented to the rfaF gene.


Assuntos
Bradyrhizobium/enzimologia , Glicosiltransferases/genética , Glicosiltransferases/metabolismo , Lipopolissacarídeos/biossíntese , Sequência de Aminoácidos , Bradyrhizobium/genética , Carboidratos Epimerases/genética , Clonagem Molecular , DNA Bacteriano/análise , Teste de Complementação Genética , Glicosiltransferases/química , Dados de Sequência Molecular , Análise de Sequência de DNA
14.
Appl Microbiol Biotechnol ; 52(3): 345-53, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10531647

RESUMO

Recombinant fusion proteins offer important new therapeutic approaches for the future. This report describes the use of three different genetic strategies (i.e. "mono-", "bi-" and "tri-cistronic" vectors) to achieve stable secretion from BHK cells of a glycosylated antibody-cytokine fusion protein designed for use in antitumour therapy. It describes selection of a robust and effective production cell line based on stability of secretion of the product, quality of mRNA and protein products and performance in in vitro bioassays for potency. The data obtained at this stage were utilised in the selection of a suitable candidate production cell line. The relative productivity and general performance of the cells in stirred tank and fixed bed culture systems indicated that a variety of cell culture technologies provided robust tools for production of a highly selected cell clone. Consistency of the product glycosylation was determined by analysis of released oligosaccharides using matrix-assisted laser desorption ionisation-time of flight mass spectrometry and high-performance anion exchange chromatography. These investigations showed consistent expression of three glycoforms of the fusion protein which varied in their relative proportions in different culture systems and at different time points in a fixed bed reactor with continuous perfusion. In conclusion, this study dealt with a range of important scientific and technical issues which are essential for regulatory approval and commercial success of a recombinant protein and elucidates some useful markers for process development for similar recombinant biologicals.


Assuntos
Antineoplásicos/metabolismo , Vetores Genéticos/genética , Imunoglobulina G/genética , Proteínas Recombinantes de Fusão/biossíntese , Fator de Necrose Tumoral alfa/genética , Animais , Antineoplásicos/isolamento & purificação , Reatores Biológicos , Sequência de Carboidratos , Linhagem Celular , Cromatografia Líquida de Alta Pressão , Cricetinae , Meios de Cultura Livres de Soro , Ensaios de Seleção de Medicamentos Antitumorais , Receptores ErbB/imunologia , Genes/genética , Genes Sintéticos , Glicosilação , Rim , Mesocricetus , Dados de Sequência Molecular , Oligossacarídeos/química , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Seleção Genética , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Células Tumorais Cultivadas/efeitos dos fármacos
15.
J Bacteriol ; 181(5): 1544-54, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10049387

RESUMO

Examination of nolA revealed that NolA can be uniquely translated from three ATG start codons. Translation from the first ATG (ATG1) predicts a protein (NolA1) having an N-terminal, helix-turn-helix DNA-binding motif similar to the DNA-binding domains of the MerR-type regulatory proteins. Translation from ATG2 and ATG3 would give the N-terminally truncated proteins NolA2 and NolA3, respectively, lacking the DNA-binding domain. Consistent with this, immunoblot analyses of Bradyrhizobium japonicum extracts with a polyclonal antiserum to NolA revealed three distinct polypeptides whose molecular weights were consistent with translation of nolA from the three ATG initiation sites. Site-directed mutagenesis was used to produce derivatives of nolA in which ATG start sites were sequentially deleted. Immunoblots revealed a corresponding absence of the polypeptide whose ATG start site was removed. Translational fusions of the nolA mutants to a promoterless lacZ yielded functional fusion proteins in both Escherichia coli and B. japonicum. Expression of NolA is inducible upon addition of extracts from 5-day-old etiolated soybean seedlings but is not inducible by genistein, a known inducer of the B. japonicum nod genes. The expression of both NolA2 and NolA3 requires the presence of NolA1. NolA1 or NolA3 is required for the genotype-specific nodulation of soybean genotype PI 377578.


Assuntos
Regiões 5' não Traduzidas , Proteínas de Bactérias/genética , Bradyrhizobium/genética , Regulação Bacteriana da Expressão Gênica , Regiões Promotoras Genéticas , Fatores de Transcrição , Transcrição Gênica , Animais , Anticorpos , Proteínas de Bactérias/análise , Proteínas de Bactérias/biossíntese , Sequência de Bases , Cromossomos Bacterianos , Sequências Hélice-Volta-Hélice , Dados de Sequência Molecular , Biossíntese de Proteínas , Coelhos , Proteínas Recombinantes de Fusão/biossíntese , Mapeamento por Restrição , Deleção de Sequência , beta-Galactosidase/biossíntese , beta-Galactosidase/genética
16.
Cytotechnology ; 26(1): 59-64, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22359007

RESUMO

In this work a recombinant BHK21 clone producing a fusion protein with potential application in tumour target therapy was adapted to five different serum-free media (SFM) and to a protein-free medium (PFM). Only the PFM did not require a gradual adaptation to cell growth in the absence of serum. All tested SFM required a gradual adaptation (up to 35 days). For the majority of the SFM tested, cell specific productivity was not affected by the decrease in serum concentration during adaptation; however, cell growth was significantly affected by the serum decrease. Both cell growth and productivity were increased when PFM SMIF6 was used instead of the control medium. Long term measurements (approximately 100 days) of cell specific productivity for PFM and the two best SFM showed that productivity was maintained. This indicates the media capability to be used in long term production processes.

18.
Cytotechnology ; 24(3): 253-9, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22358769

RESUMO

We have used a recombinant adenovirus vector (E1-) expressing ß-galactosidase to explore a novel mechanism with which to transfer genes into cells of the central nervous system (CNS). The replication-deficient adenovirus vector expressing ß-galactosidase (RAd35) was propagated on a permissive helper cell line (293 cells). High level protein expression from the human cytomegalovirus immediate early promoter (hCMV IE) was obtained in a target cell population of RAd35 infected cultured neuronal and glial cell lines. Light microscopy showed that over 50% of the glial cells studied expressed ß-galactosidase. Following retinoic acid treatment, RAd35 infected cell lines ND7/23, NG108 and NTera2, showed ß-galactosidase expression in up to 90% of the cells. In addition, these cells showed morphological evidence of differentiation into neurons. This pattern of ß-galactosidase expression was also observed in primary rat cerebella granule neuron cultures. In vivo studies were performed in Balb/c mice following direct intracranial injections of RAd35 into the brain. Cell sections showed a localised staining in the brain at the site of injection of the virus. Non-replicating adenovirus vectors are therefore highly efficient systems for delivering a transgene into brain cells. However, their broad cell tropism may limit their applications for genetic disorders in which a specific cell type is to be targeted for gene therapy. To address this problem, we have constructed adenovirus vectors which contain specific neuronal promoters and are currently assessing in vitro expression.

19.
Plant Physiol ; 110(1): 171-8, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8587981

RESUMO

Previously, we reported the isolation of a peptide transport gene designated AtPTR2 from Arabidopsis thaliana by functional complementation of a yeast peptide transport mutant. We now report the isolation of a second peptide transport gene (AtPTR2-B) from Arabidopsis using the same approach. Similar to the effects of transferring AtPTR2-A (previously called AtPTR2), transfer of AtPTR2-B to yeast peptide transport mutants restored the ability to grow on di- and tripeptides but not peptides four residues or longer. However, unlike yeast mutants complemented with either the yeast PTR2 gene or the AtPTR2-A gene, transformants expressing AtPTR2-B were only partially sensitive to toxic peptides. Northern analysis showed that AtPTR2-B was constitutively expressed in all plant organs. Studies of the kinetics indicated that AtPTR2-A and AtPTR2-B have Km values of 47 and 14 microM, respectively, with Vmax values of 0.061 and 0.013 nmol mg-1 cell dry weight s-1, respectively, when dileucine was used as a substrate. AtPTR2-B is encoded on a 2.0-kb cDNA corresponding to a 585-amino acid protein (64.4 kD). Hydropathy analysis indicates that the protein is highly hydrophobic and suggests that there are 12 putative transmembrane segments. AtPTR2-B, like AtPTR2-A, shares significant similarity to a number of other proteins involved in transport of peptides into cells.


Assuntos
Proteínas de Arabidopsis , Arabidopsis/genética , Proteínas de Transporte/genética , Genes de Plantas , Proteínas de Membrana Transportadoras , Peptídeos/metabolismo , Proteínas de Plantas/genética , Sequência de Aminoácidos , Transporte Biológico , Dipeptídeos/metabolismo , Dipeptídeos/toxicidade , Teste de Complementação Genética , Cinética , Técnicas de Sonda Molecular , Dados de Sequência Molecular , Oligopeptídeos/metabolismo , Oligopeptídeos/toxicidade , Peptídeos/toxicidade , RNA Mensageiro/análise , RNA de Plantas/análise , Proteínas Recombinantes , Saccharomyces cerevisiae/genética , Análise de Sequência de DNA
20.
J Bacteriol ; 176(21): 6717-29, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7961425

RESUMO

To understand the genetic mechanism of host specificity in the interaction between rhizobia and their hosts, it is important to identify genes that influence both early and late steps in symbiotic development. This paper focuses on the little-understood genetics of host-specific nitrogen fixation. A deletion mutant of Bradyrhizobium japonicum, strain NAD163, was found to induce effective, nitrogen-fixing nodules on soybean and siratro plants but produced ineffective nodules on cowpea plants. Additional transposon and deletion mutants defined a small region that conferred this phenotype, and this region was sequenced to identify two putative open reading frames (ORFs). Data indicate that only one of these ORFs is detectable in bacteroids. This ORF was termed hsfA, with a predicted protein product of 11 kDa. The transcriptional start site of hsfA was determined and found to coincide with a predicted RpoN-dependent promoter. Microscopic studies of nodules induced by the wild type and hsfA mutants on cowpea and soybean plants indicate that the cowpea mutant nodules are slow to develop. The data indicate that hsfA appears to play a crucial role in bacteroid development on cowpea but does not appear to be essential for nitrogen fixation on the other hosts tested.


Assuntos
Proteínas de Bactérias/genética , Genes Bacterianos/genética , Fixação de Nitrogênio/genética , Plantas/microbiologia , Rhizobiaceae/genética , Sequência de Aminoácidos , Sequência de Bases , Fabaceae/microbiologia , Fabaceae/ultraestrutura , Dados de Sequência Molecular , Mutagênese , Fenótipo , Raízes de Plantas/microbiologia , Raízes de Plantas/ultraestrutura , Tumores de Planta/microbiologia , Plantas/ultraestrutura , Plantas Medicinais , Rhizobiaceae/ultraestrutura , Análise de Sequência de DNA , Deleção de Sequência , Especificidade da Espécie , Simbiose/genética , Transcrição Gênica
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