RESUMO
Acute intermittent porphyria (AIP) is a human disease resulting from a dominantly inherited partial deficiency of the heme biosynthetic enzyme, porphobilinogen deaminase (PBGD). The frequency of the trait for AIP is 1/10,000 in most populations, but may be markedly higher (1/500) in psychiatric patients. The clinical expression of the disease is characterized by acute, life-threatening attacks of 'porphyric neuropathy' that include abdominal pain, motor and sensory neurological deficits and psychiatric symptoms. Attacks are frequently precipitated by drugs, alcohol and low caloric intake. Identical symptoms occur in other hepatic porphyrias. To study the pathogenesis of the neurologic symptoms of AIP we have generated Pbgd-deficient mice by gene targeting. These mice exhibit the typical biochemical characteristics of human AIP, notably, decreased hepatic Pbgd activity, increased delta-aminolevulinic acid synthase activity and massively increased urinary excretion of the heme precursor, delta-aminolevulinic acid after treatment with drugs such as phenobarbital. Behavioural tests reveal decreased motor function and histopathological findings include axonal neuropathy and neurologic muscle atrophy.
Assuntos
Doenças do Sistema Nervoso/etiologia , Porfiria Aguda Intermitente , Porfiria Aguda Intermitente/metabolismo , Ácido Aminolevulínico/urina , Animais , Atrofia , Axônios/patologia , Sequência de Bases , Quimera , Modelos Animais de Doenças , Feminino , Marcação de Genes , Humanos , Hidroximetilbilano Sintase/genética , Rim/efeitos dos fármacos , Fígado/química , Masculino , Camundongos , Dados de Sequência Molecular , Atividade Motora , Músculo Esquelético/patologia , Doenças do Sistema Nervoso/enzimologia , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/patologia , Fenobarbital/farmacologia , Porfiria Aguda Intermitente/enzimologia , Porfiria Aguda Intermitente/genética , Porfiria Aguda Intermitente/patologia , RNA Mensageiro/análiseRESUMO
In mature B lymphocytes, the zinc finger transcription factor early growth response 1 (Egr-1) is one of the many immediate-early genes induced upon B cell antigen receptor engagement. However, its role during earlier stages of lymphopoiesis has remained unclear. By examining bone marrow B cell subsets, we found Egr-1 transcripts in pro/pre-B and immature B lymphocytes, and Egr-1 protein in pro/pre-B-I cells cultivated on stroma cells in the presence of interleukin (IL)-7. In recombinase-activating gene (RAG)-2-deficient mice overexpressing an Egr-1 transgene in the B lymphocyte lineage, pro/pre-B-I cells could differentiate past a developmental block at the B220(low) BP-1(-) stage to the stage of B220(low) BP-1(+) pre-B-I cells, but not further to the B220(low) BP-1(+) CD25(+) stage of pre-B-II cells. Therefore, during early B lymphopoiesis progression from the B220(low) BP-1(-) IL-2R- pro/pre-B-I stage to the B220(low) BP-1(+) IL-2R+ pre-B-II stage seems to occur in at least two distinct steps, and the first step to the stage of B220(low) BP-1(+) pre-B-I cells can be promoted by the overexpression of Egr-1 alone. Wild-type mice expressing an Egr-1 transgene had increased proportions of mature immunoglobulin (Ig)M+ B220(high) and decreased proportions of immature IgM+ B220(low) bone marrow B cells. Since transgenic and control precursor B cells show comparable proliferation patterns, overexpression of Egr-1 seems also to promote entry into the mature B cell stage. Analysis of changes in the expression pattern of potential Egr-1 target genes revealed that Egr-1 enhances the expression of the aminopeptidase BP-1/6C3 in pre-B and immature B cells and upregulates expression of the orphan nuclear receptor nur77 in IgM+ B cells.
Assuntos
Linfócitos B/citologia , Proteínas de Ligação a DNA/metabolismo , Células-Tronco Hematopoéticas/citologia , Proteínas Imediatamente Precoces , Leucopoese , Fatores de Transcrição/metabolismo , Animais , Linfócitos B/metabolismo , Células da Medula Óssea , Diferenciação Celular , Divisão Celular , Linhagem Celular , DNA/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/fisiologia , Proteína 1 de Resposta de Crescimento Precoce , Feminino , Expressão Gênica , Regulação da Expressão Gênica , Células-Tronco Hematopoéticas/metabolismo , Fígado/embriologia , Masculino , Metaloendopeptidases/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Mutação , Membro 1 do Grupo A da Subfamília 4 de Receptores Nucleares , Receptores Citoplasmáticos e Nucleares , Receptores de Esteroides , Elementos de Resposta/genética , Fatores de Transcrição/genéticaRESUMO
The influence of antigen epitope density and order on B cell induction and antibody production was assessed with the glycoprotein of vesicular stomatitis virus serotype Indiana [VSV-G (IND)]. VSV-G (IND) can be found in a highly repetitive form the envelope of VSV-IND and in a poorly organized form on the surface of infected cells. In VSV-G (IND) transgenic mice, B cells were unresponsive to the poorly organized VSV-G (IND) present as self antigen but responded promptly to the same antigen presented in the highly organized form. Thus, antigen organization influences B cell tolerance.
Assuntos
Anticorpos Antivirais/biossíntese , Linfócitos B/imunologia , Tolerância Imunológica , Glicoproteínas de Membrana , Vírus da Estomatite Vesicular Indiana/imunologia , Proteínas do Envelope Viral/imunologia , Animais , Anticorpos Antivirais/imunologia , Afinidade de Anticorpos , Imunização , Imunoglobulina G/biossíntese , Imunoglobulina M/biossíntese , Ativação Linfocitária , Macrófagos Peritoneais/microbiologia , Camundongos , Camundongos Transgênicos , Testes de Neutralização , Linfócitos T Auxiliares-Indutores/imunologia , Vírus da Estomatite Vesicular Indiana/fisiologiaRESUMO
Two molecular mechanisms of T cell-mediated cytotoxicity, one perforin-based, the other Fas-based, have been demonstrated. To determine the extent of their contribution to T cell-mediated cytotoxicity, a range of effector cells from normal control or perforin-deficient mice were tested against a panel of target cells with various levels of Fas expression. All cytotoxicity observed was due to either of these mechanisms, and no third mechanism was detected. Thus, the perforin- and Fas-based mechanisms may account for all T cell-mediated cytotoxicity in short-term in vitro assays.
Assuntos
Antígenos de Superfície/imunologia , Citotoxicidade Imunológica , Glicoproteínas de Membrana/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Animais , Células Cultivadas , Concanavalina A/farmacologia , Ionomicina/farmacologia , Leucemia L1210 , Teste de Cultura Mista de Linfócitos , Vírus da Coriomeningite Linfocítica/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Dados de Sequência Molecular , Perforina , Proteínas Citotóxicas Formadoras de Poros , Acetato de Tetradecanoilforbol/farmacologia , Células Tumorais Cultivadas , Receptor fasRESUMO
The effects of topical administration of 3-methylcholanthrene (MCA) or its metabolites on BALB/cKi mice were reported on inflammatory skin reactions, the alterations in epidermal thickness, the number of nucleated cells, pyknotic nuclei and/or nuclear fragments, and mitotic figures in the interfollicular epidermis (IFE). In the two-stage carcinogenesis system, MCA, the powerful complete carcinogen, induced an ordered sequence of cell changes strikingly similar to those caused by tumor-promoting agents such as the phorbol esters. These changes were absent after application of the "K-region" oxide of MCA. Other MCA metabolites also failed to induce notable inflammation, epidermal hyperplasia, and/or hypertrophy. Several MCA derivatives, however, caused a thinning of IFE paralleled by an increase in the relative number of pyknotic nuclei and a decrease in the total number of epithelial cells. The inhibitor of polycyclic hydrocarbon metabolism alpha-naphthoflavone did not prevent MCA-mediated skin reactions but, under suitable conditions, apparently potentiated the hyperplastic effects of MCA. The findings indicate that important events in the promotion phase of MCA-mediated skin carcinogenesis might be associated with the parent compound rather than with one of its metabolites.
Assuntos
Metilcolantreno , Pele/efeitos dos fármacos , Administração Tópica , Animais , Núcleo Celular/patologia , Dermatite de Contato , Relação Dose-Resposta a Droga , Flavonoides/farmacologia , Hiperplasia/induzido quimicamente , Cinética , Masculino , Metilcolantreno/administração & dosagem , Metilcolantreno/análogos & derivados , Camundongos , Camundongos Endogâmicos BALB C , Mitose/efeitos dos fármacos , Lesões Pré-Cancerosas/induzido quimicamente , Pele/patologia , Pele/ultraestrutura , Relação Estrutura-AtividadeRESUMO
Risk assessment for the deliberate release of microorganisms into the environment is traditionally carried out on a case-by-case basis. In a similar approach to that used when assessing human pathogenicity, we propose an alternative approach by introducing risk classes to facilitate or complement this type of risk assessment. These consider several sets of scenarios that address the different values that need to be protected. Examples of this approach include risk-class definitions for soil fertility and biodiversity.
Assuntos
Biotecnologia/organização & administração , Biotecnologia/normas , Poluição Ambiental/prevenção & controle , Bactérias/classificação , Bactérias/patogenicidade , Reatores Biológicos/efeitos adversos , Reatores Biológicos/normas , Ecossistema , Europa (Continente) , Humanos , Microbiologia/legislação & jurisprudência , Medição de Risco/métodos , Medição de Risco/normas , Gestão de Riscos , Poluentes do Solo/normas , Abastecimento de Água/normasRESUMO
Abundant neurofibrillary tangles, neuropil threads and plaque neurites constitute the neurofibrillary pathology of Alzheimer's disease. They form in the nerve cells that undergo degeneration in the disease where their regional distribution correlates with the degree of dementia. Each lesion contains the paired helical filament (PHF) as its major fibrous component. Recent work has shown that PHFs are composed of the microtubule-associated protein tau in a hyperphosphorylated state. PHF-tau is hyperphosphorylated on six adult brain tau isoforms. As a consequence, tau is unable to bind to microtubules and is believed to self-assemble into the PHF. Current evidence suggests that protein kinases or protein phosphatases with a specificity for serine/threonine-proline residues play an important role in the hyperphosphorylation of tau. Candidate protein kinases include mitogen-activated protein kinase, glycogen synthase kinase-3 and cyclin-dependent kinase 5, whereas the trimeric form of protein phosphatase 2A is a candidate phosphatase.
Assuntos
Neurofibrilas/química , Neurofibrilas/ultraestrutura , Idoso , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Sequência de Aminoácidos , Encéfalo/fisiologia , Encéfalo/ultraestrutura , Química Encefálica/fisiologia , Humanos , Isomerismo , Dados de Sequência Molecular , Proteínas tau/química , Proteínas tau/ultraestruturaRESUMO
The beta-amyloid precursor protein (APP) carries mutations in codons 717 or 670/671, which cosegregate with familial forms of Alzheimer's disease (AD). As an initial step to study the related pathogenetic mechanisms in vivo we have generated transgenic mice expressing APP with these mutations. Several neuron-specific promoters were used to drive expression of human APP cDNAs. Only the Thy-1 promoter yielded transgene expression levels comparable to or above the endogenous mouse levels. Deletion of a 121 bp sequence from the 3' untranslated region of APP appeared to increase mRNA levels. Transgene mRNA was found throughout the brain with highest levels in hippocampus and cerebral cortex. Accordingly, human APP was detected in these regions by Western blotting. Protein levels paralleled mRNA levels reaching or exceeding the amount of endogenous APP. Variable reactivity of human APP in cell bodies was shown by immunocytochemistry. Although our initial histological examinations did not reveal any alterations characteristic of AD, further studied will be required.
Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Precursor de Proteína beta-Amiloide/biossíntese , Precursor de Proteína beta-Amiloide/genética , Neurônios/metabolismo , Envelhecimento/metabolismo , Animais , Sequência de Bases , Northern Blotting , Western Blotting , Química Encefálica/efeitos dos fármacos , Química Encefálica/fisiologia , Proteínas de Ligação a DNA , Humanos , Imuno-Histoquímica , Hibridização In Situ , Proteínas com Domínio LIM , Camundongos , Camundongos Transgênicos , Dados de Sequência Molecular , Proteínas Nucleares , Proteínas Oncogênicas , Fosfopiruvato Hidratase/farmacologia , RNA Mensageiro/biossíntese , Fatores de Transcrição/farmacologiaRESUMO
BALB/c is one of the most widely used and best characterized mouse strains in immunology. For various applications, it is necessary to generate BALB/c transgenic mice. However, using the conventional microinjection technique it is extremely inefficient to produce transgenic BALB/c mice since the one-cell stage BALB/c embryos are highly vulnerable to pronuclear DNA microinjection. To overcome this problem, we have investigated the generation of Egr-1 (early growth response gene) transgenic mice via the transfection of BALB/c embryonic stem cells. Transfectants carrying Egr-1 constructs comprising either the immunoglobulin heavy chain or the MHC class II promoter/enhancer system were injected into C57BL/6 host blastocysts resulting in chimeric mice. For both type of expression vectors, transgenic offspring of the germline chimeras expressed recombinant Egr-1 in lymphoid tissues containing B cells. This demonstrates the successful generation of Egr-1 transgenic BALB/c mice using transfected ES cell.
Assuntos
Embrião de Mamíferos/citologia , Camundongos Endogâmicos BALB C/genética , Camundongos Transgênicos/genética , Células-Tronco/metabolismo , Animais , Southern Blotting , Linhagem Celular , Proteínas de Ligação a DNA/biossíntese , Proteínas de Ligação a DNA/genética , Proteína 1 de Resposta de Crescimento Precoce , Feminino , Proteínas Imediatamente Precoces/genética , Camundongos , Proteínas Recombinantes/biossíntese , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Transfecção/genética , Transfecção/métodosRESUMO
CD30-positive large cell cutaneous T-cell lymphomas are known to be associated with the human T-cell leukemia/lymphoma virus type I. We present a case of anaplastic large cell lymphoma that recurred three times during 9 years at different sites. Molecular studies [polymerase chain reaction (PCR), in situ hybridization] showed Epstein-Barr virus (EBV) genome in biopsy samples of this first reported case of EBV-associated cutaneous anaplastic large cell lymphoma. This case was human T-lymphotropic virus-1 and -2 negative by PCR. The results add some evidence to the hypothesis that EBV may be a factor in the pathogenesis of cutaneous lymphoproliferative lesions.
Assuntos
Herpesvirus Humano 4/isolamento & purificação , Linfoma Difuso de Grandes Células B/etiologia , Neoplasias Cutâneas/etiologia , Infecções Tumorais por Vírus/complicações , Sequência de Bases , DNA Viral/análise , Genoma Viral , Herpesvirus Humano 4/genética , Humanos , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Neoplasias Cutâneas/patologia , Infecções Tumorais por Vírus/patologiaRESUMO
BACKGROUND: The role of T lymphocytes in acute allograft rejection is well established. The involvement of B lymphocytes in this process, however, is more controversial. A series of reports showed that mice without a functional B-cell compartment rejected allografts with the same kinetics as control animals. In rats, however, alloantibodies were found to play a decisive role in allograft rejection. To provide an explanation for the discrepant results, we readdressed the role of B cells and antibodies in mice with disrupted immunoglobulin mu chain genes. The use of cyclosporine (CsA), which strongly suppresses T cells, allowed us to focus specifically on the function of B cells. METHODS: C57BL/6 mice rendered B cell deficient by targeted disruption of the immunoglobulin mu chain gene (referred to as microMT/microMT mice) and microMT/+ control mice with one functional mu chain were heterotopically transplanted with fully MHC-disparate BALB/c hearts. CsA was administered subcutaneously by Alzet osmotic pumps. Normal and immune serum specific for donor hearts was given to assess the role of antibodies in the rejection process. RESULTS: Both B cell-deficient microMT/microMT and heterozygous microMT/+ mice were found to reject transplanted hearts within a similar period of time. In contrast, when T cells were partially suppressed with CsA, graft survival was significantly prolonged in microMT/microMT mice as compared with heterozygous controls. Passive transfer of donor-specific immune serum, obtained from microMT/+ animals rejecting allogeneic hearts, to CsA-treated microMT/microMT mice significantly accelerated allograft rejection as opposed to recipients treated with normal serum. CONCLUSIONS: B lymphocytes and antibodies play an important role in acute allograft rejection particularly when the dominant T-cell compartment is partially suppressed.
Assuntos
Rejeição de Enxerto/imunologia , Transplante de Coração/imunologia , Isoanticorpos/imunologia , Animais , Linfócitos B/fisiologia , Ciclosporina/farmacologia , Marcação de Genes , Soros Imunes/imunologia , Imunoglobulina G/genética , Cadeias mu de Imunoglobulina/genética , Imunossupressores/farmacologia , Camundongos , Camundongos Endogâmicos BALB C/imunologia , Camundongos Endogâmicos C57BL/genética , Baço/citologia , Baço/imunologia , Linfócitos T/fisiologia , Fatores de Tempo , Transplante Homólogo/imunologiaRESUMO
Sixty-eight patients with "advanced ovarian carcinoma" were entered into an ongoing phase-II trial for remission induction with cis-platinum (DDP) 80 mg/m2 i.v. on day 1 followed by forced saline diuresis, melphalan (L-PAM) 12 mg/m2 i.v. on day 2 and hexamethylmelamine (HMM) 130 mg/m2 p.o. X 14 days from days 8-21 in six monthly cycles following operative resection and/or staging. Fifty-one patients were evaluable for response, ten had not completed six courses and could not be assessed, two patients died early (one probably of toxicity), and five patients refused treatment and follow-up. Thirty-Two patients had serous, endometrioid or undifferentiated carcinomas of the ovary. Of these, 11 (35%) achieved a pathologically proven complete remission (CR), five (16%) were NED after second-look (residual disease in ovary or removed omentum with all other biopsies and cytology washings negative), eight (32%) achieved a partial remission (PR), and three (12%) had progressive disease. None of the seven patients with clear-cell carcinoma and none of the three patients with Mullerian tumor of the ovary responded. Six of nine patients with tumors of uncertain origin or proven metastasis to ovary did not respond to treatment. These preliminary results indicate that advanced ovarian carcinomas form a heterogeneous group of recognizable neoplastic diseases with striking variation in response to treatment.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Altretamine/administração & dosagem , Cisplatino/administração & dosagem , Avaliação de Medicamentos , Feminino , Humanos , Melfalan/administração & dosagem , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/tratamento farmacológico , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/secundário , Prognóstico , ReoperaçãoRESUMO
After treatment of postmeiotic stages of spermatogenesis of the mouse with TEM, dose and stage of spermatogenesis-dependent disturbances of the early embryonic development can be observed both in vivo and after in vitro culture of the embryos. The observations in both systems can be correlated. The embryo-culture system thereby enables analysis of the expression of mutagen-induced damage more accurately than the in vivo dominant lethal test. With the doses used (0.2 and 0.4 mg/kg) TEM-treatment of the fathers did not affect the rate of fertilized and cleaving eggs during the first three weeks post-treatment but severely disturbed the further development of the embryos at all stages up to implantation, exhibiting a maximum effect on morulae.
Assuntos
Espermatogênese/efeitos dos fármacos , Trietilenomelamina/farmacologia , Animais , Técnicas de Cultura , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Feminino , Genes Dominantes , Genes Letais , Técnicas Genéticas , Masculino , Camundongos , Camundongos Endogâmicos DBA , Camundongos EndogâmicosRESUMO
After treatment of postmeiotic stages of spermatogenesis of the mouse with TEM (0.2 or 0.4 mg/kg), dose- and stage-of-spermatogenesis-dependent frequencies of cytogenetic aberrations can be observed in early embryos. The frequencies of first-cleavage metaphases exhibiting structural aberrations (all of the chromosome type), the frequencies of 2 cell embryos and of 4--8 cell embryos containing nuclei accompanied by micronuclei or nuclei connected by bridges show a close correlation to frequencies of preimplantation loss of embryos recorded in a dominant lethal test. The frequencies of morulae/blastulae exhibiting blastomeres with micronuclei show a close correlation to the frequencies of total (pre- and post-implantation) loss of embryos. This indicates delayed expression of TEM-induced chromosomal damage which could persist undetected in very early stages of embryogenesis.
Assuntos
Aberrações Cromossômicas , Cromossomos/efeitos dos fármacos , Espermatócitos/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Trietilenomelamina/farmacologia , Animais , Feminino , Frequência do Gene , Genes Dominantes , Genes Letais , Masculino , Camundongos , Camundongos Endogâmicos DBA , MutagênicosRESUMO
Tribromoethanol is widely used as an anaesthetic agent for embryo-transfer surgery for the generation of transgenic mice. Potential side effects such as local irritation, fibrous adhesions in the abdominal cavity, and mortalities of unknown cause have been reported. Mice of three different strains (CD-1, OF-1, NMRI) received intraperitoneal injections of pentobarbiturate (60 mg/kg, 0.4%), tribromoethanol (240 mg/kg, 1.2%), tribromoethanol (450 mg/kg, 2.5%), ketamine/xylazine (120 mg/kg, 1.2%/16 mg/kg, 0.16%) or saline (NaCl, 0.9%). After 24 h the animals were sacrificed and blinded histopathological examination of abdominal organs was performed by light microscopy. Tribromoethanol caused focal to diffuse necrosis primarily of subperitoneal muscle fibres of the abdominal wall, and, occasionally, necrotic changes on the surface of abdominal organs. These changes were associated with acute peritoneal inflammation and fibrinous serositis of the abdominal organs. The severity of the findings increased with the concentration of tribromoethanol. The use of ketamine/xylazine yielded a comparable success rate in embryo transfer without undesirable side effects. Further use of tribromoethanol is not recommended.
Assuntos
Anestésicos/efeitos adversos , Etanol/análogos & derivados , Animais , Transferência Embrionária , Etanol/efeitos adversos , Feminino , Ketamina/efeitos adversos , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Camundongos Transgênicos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Gravidez , Taxa de Gravidez , Baço/efeitos dos fármacos , Baço/patologia , Xilazina/efeitos adversosRESUMO
To test the potential usefulness of transgenic rabbits as production systems for human proteins of pharmaceutical value, we cloned the rabbit beta-casein promoter and fused it to the genomic sequence of the human interleukin-2 (hIL2) gene. Four transgenic female rabbits were tested for expression and biological activity of the foreign protein in their milk. The milk of all four females proved to contain biologically active hIL2. The results show that transgenic rabbits may represent a convenient and economic system for the rapid production of biologically active protein in milk.
Assuntos
Animais Geneticamente Modificados/metabolismo , Caseínas/genética , Interleucina-2/metabolismo , Proteínas do Leite/genética , Leite/análise , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional , Coelhos/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Animais , Sequência de Bases , Feminino , Humanos , Proteínas do Leite/metabolismo , Dados de Sequência Molecular , Especificidade de Órgãos , Coelhos/genéticaAssuntos
Éteres Cíclicos/farmacologia , Hidroliases/antagonistas & inibidores , Hidrocarbonetos Clorados/farmacologia , Metilcolantreno , Neoplasias Cutâneas/induzido quimicamente , Administração Tópica , Animais , Benzopirenos , Fenômenos Químicos , Química , DNA , Sinergismo Farmacológico , Masculino , Camundongos , Camundongos Endogâmicos BALB C , NADP , Neoplasias Experimentais/induzido quimicamente , Pele/efeitos dos fármacosAssuntos
Citosol/metabolismo , Fígado/metabolismo , Metilcolantreno/farmacologia , Oxigenases de Função Mista/biossíntese , Acetatos/biossíntese , Animais , Sítios de Ligação/efeitos dos fármacos , Biotransformação , Isótopos de Carbono , Citosol/efeitos dos fármacos , Indução Enzimática/efeitos dos fármacos , Feminino , Hidrocarbonetos/metabolismo , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Linfonodos/efeitos dos fármacos , Linfonodos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos AKR , Ligação Proteica/efeitos dos fármacos , Pele/efeitos dos fármacos , Pele/metabolismo , Baço/efeitos dos fármacos , Baço/metabolismoAssuntos
Metilcolantreno/análogos & derivados , Metilcolantreno/toxicidade , Neoplasias Cutâneas/induzido quimicamente , Pele/efeitos dos fármacos , Administração Tópica , Animais , Autorradiografia , Benzopirenos , Éteres Cíclicos/farmacologia , Hidrocarbonetos Clorados/farmacologia , Hiperplasia/patologia , Hipertrofia/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitose , Oxigenases de Função Mista/metabolismo , Neoplasias Experimentais/induzido quimicamente , Neoplasias Experimentais/enzimologia , Neoplasias Experimentais/patologia , Pele/patologia , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/patologia , Fatores de TempoRESUMO
In this study the Nano Spray Dryer B-90 (BÜCHI Labortechnik AG, Flawil, Switzerland) was evaluated with regard to the drying of proteins and the preparation of respirable powders in the size range of 1-5 µm. ß-galactosidase was chosen as a model protein and trehalose was added as a stabilizer. The influence of inlet temperature, hole size of the spray cap membrane and ethanol concentration in the spray solution was studied using a 3³ full factorial design. The investigated responses were enzyme activity, particle size, span, yield and shelf life. Furthermore, the particle morphology was examined. The inlet temperature as well as the interaction of inlet temperature and spray cap size significantly influenced the enzyme activity. Full activity was retained with the optimized process. The particle size was affected by the hole size of the spray cap membrane and the ethanol content. The smallest cap led to a monodisperse particle size distribution and the greatest yield of particles of respirable size. Higher product recovery was achieved with lower inlet temperatures, higher ethanol contents and smaller cap sizes. Particle morphology differed depending on the cap size. The protein exhibited higher storage stability when spray dried without ethanol and when a larger spray cap size was used.