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1.
Br J Dermatol ; 164(3): 633-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21375515

RESUMO

BACKGROUND: The sap from Euphorbia peplus, commonly known as petty spurge in the U.K. or radium weed in Australia, has been used as a traditional treatment for a number of cancers. OBJECTIVE: To determine the effectiveness of E. peplus sap in a phase I/II clinical study for the topical treatment of basal cell carcinomas (BCC), squamous cell carcinomas (SCC) and intraepidermal carcinomas (IEC). METHODS: Thirty-six patients, who had refused, failed or were unsuitable for conventional treatment, were enrolled in a phase I/II clinical study. A total of 48 skin cancer lesions were treated topically with 100-300 µL of E. peplus sap once daily for 3 days. RESULTS: The complete clinical response rates at 1 month were 82% (n = 28) for BCC, 94% (n = 16) for IEC and 75% (n = 4) for SCC. After a mean follow-up of 15 months these rates were 57%, 75% and 50%, respectively. For superficial lesions < 16 mm, the response rates after follow-up were 100% for IEC (n = 10) and 78% for BCC (n = 9). CONCLUSIONS: The clinical responses for these relatively unfavourable lesions (43% had failed previous treatments, 35% were situated in the head and neck region and 30% were > 2 cm in diameter), are comparable with existing nonsurgical treatments. An active ingredient of E. peplus sap has been identified as ingenol mebutate (PEP005). This clinical study affirms community experience with E. peplus sap, and supports further clinical development of PEP005 for the treatment of BCC, SCC and IEC.


Assuntos
Carcinoma in Situ/tratamento farmacológico , Carcinoma Basocelular/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Euphorbiaceae , Extratos Vegetais/uso terapêutico , Neoplasias Cutâneas/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma in Situ/patologia , Carcinoma Basocelular/patologia , Carcinoma de Células Escamosas/patologia , Estudos de Coortes , Humanos , Pessoa de Meia-Idade , Fitoterapia/métodos , Neoplasias Cutâneas/patologia
2.
Br Dent J ; 203(10): 601-5, 2007 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-18037853

RESUMO

OBJECTIVES: To assess dental students' posture on two different seats in order to determine if one seat predisposes to a difference in working posture. DESIGN: A between-subject experimental design was selected. SETTING: The study was undertaken at the University of Birmingham School of Dentistry in 2006. Subjects (materials) and methods Sixty second year dental students at the University of Birmingham who were attending their fi rst classes in the phantom head laboratory were randomly selected and allocated to two different seats (30 Bambach Saddle Seats and 30 conventional seats). Students were trained in the use of the seats. After ten weeks, the students were observed, photographs were taken by the researcher and these were assessed using Rapid Upper Limb Assessment (RULA). MAIN OUTCOME MEASURES: The posture of the students was assessed using the RULA. Each student was given a risk score. A Mann Whitney test was used for statistical analysis. RESULTS: The results indicated that the students using the conventional seat recorded significantly higher risk scores (p <0.05) when compared with the students using Bambach Saddle Seat, suggesting an improvement in posture when using the Bambach Saddle Seat. CONCLUSION: RULA has identified that dental students using a Bambach Saddle Seat were able to maintain an acceptable working posture during simulated dental treatment and this seating may reduce the development of work-related musculoskeletal disorders.


Assuntos
Ergonomia/instrumentação , Doenças Musculoesqueléticas/prevenção & controle , Doenças Profissionais/prevenção & controle , Postura , Estudantes de Odontologia , Extremidade Superior/fisiologia , Equipamentos Odontológicos , Desenho de Equipamento , Humanos , Projetos Piloto , Postura/fisiologia , Estatísticas não Paramétricas
3.
Clin Oncol (R Coll Radiol) ; 17(5): 332-6, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16097563

RESUMO

AIMS: To describe the toxicity and response seen in patients receiving moderate-dose radiation therapy with concurrent weekly low-dose gemcitabine in the management of locally advanced non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: Eighteen patients with confirmed NSCLC were enrolled over a 17-month period from August 2000 until January 2002. All had localised disease but were considered unsuitable for curative therapy. Radiation therapy was given to a dose of 30 Gy in 15 fractions over 3 weeks. Gemcitabine was given weekly before and within 3 h of fractions 1, 6 and 11. The study was designed as a dose-escalation study, commencing at 100 mg/m2 and increasing at levels of 50 mg/m2, until the maximum tolerated dose (MTD) was reached. RESULTS: The MTD was regarded as being 150 mg/m2. The major acute toxicity observed was oesophagitis. Skin reactions were also reported. The overall response rate in all patients was 88%, with 44% achieving a complete response. CONCLUSION: The combination of gemcitabine and moderate-dose radiation therapy is feasible, and offers low toxicity and excellent response rates in patients with localised NSCLC not suitable for high-dose therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Desoxicitidina/análogos & derivados , Desoxicitidina/administração & dosagem , Neoplasias Pulmonares/radioterapia , Adulto , Idoso , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Pneumonite por Radiação/etiologia , Radioterapia/efeitos adversos , Dosagem Radioterapêutica , Fatores de Tempo , Gencitabina
4.
Clin Rehabil ; 15(3): 324-30, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11386404

RESUMO

OBJECTIVES: To investigate the accuracy in position-matching in the upper limb in two groups of subjects who were physically fit and movement aware. DESIGN: A mixed-group design was used. Objective measurement of the accuracy in position-matching at the shoulder and elbow in both dominant and nondominant arms consisted of photographic record of the position-matching test, with goniometric measurement. SETTINGS: Physiotherapy department at the Birmingham Royal Ballet and School of Health Science, University of Birmingham. SUBJECTS: Two subject groups: physiotherapy students (n = 10), professional ballet dancers (n = 10). RESULTS: A mixed design analysis of variance found significant differences between the accuracy in position-matching at both the shoulder and elbow joints in the two groups (p < 0.05), with the ballet dancers having greater accuracy then the physiotherapy students. A significant difference in the joint positions tested were demonstrated (p < 0.05) with the positions of abduction at the shoulder and extension of the elbow showing greatest accuracy in matching. There was no significant difference found between the dominant and nondominant upper limb in position-matching. CONCLUSION: Professional ballet dancers demonstrated greater accuracy in position-matching the upper limb, implying that mass and continuing practice can improve a motor sensory skill.


Assuntos
Braço/fisiologia , Dança/fisiologia , Postura/fisiologia , Propriocepção/fisiologia , Adulto , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
5.
Hum Mutat ; 17(1): 75-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11139252

RESUMO

Mutations in ATM, the gene defective in the human genetic disorder ataxia-telangiectasia (A-T), have been described in A-T patients and in a variety of tumor samples. Most of these arise due to exon skipping. We developed an RT-PCR based protein truncation test (PTT) to screen for ATM mutations in breast cancer patients showing adverse response to radiotherapy. An additional PTT product was evident in the ATM gene in peripheral blood mononuclear cells (PBMCs) from blood samples that were collected 2 days or more prior to RNA extraction. Lymphoblastoid cell lines established from the same blood samples showed no evidence of the additional band. Cloning and sequencing of the additional RT-PCR product revealed an exact deletion of exon 20 (2639 del 200), pointing to exon skipping. RT-PCR analysis of RNA extracted from freshly prepared PBMCs from 3 normal individuals showed no evidence of the additional RT-PCR product but when the blood was stored for 2-3 days prior to RNA extraction the lower molecular weight band was evident in every sample. DNA sequencing confirmed this to be due to loss of exon 20. These data suggest that mRNA-based mutation analysis on ATM should be carried out on unstored blood samples to avoid artificial loss of exons that give rise to apparent mutations.


Assuntos
Ataxia Telangiectasia/genética , Preservação de Sangue/métodos , Éxons/genética , Proteínas Serina-Treonina Quinases/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Deleção de Sequência , Processamento Alternativo , Proteínas Mutadas de Ataxia Telangiectasia , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Neoplasias da Mama/radioterapia , Proteínas de Ciclo Celular , Linhagem Celular Transformada , Análise Mutacional de DNA , Proteínas de Ligação a DNA , Humanos , Proteínas Serina-Treonina Quinases/sangue , Transcrição Gênica , Proteínas Supressoras de Tumor
6.
J Pharm Sci ; 85(12): 1301-5, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8961143

RESUMO

The antileukemia enzyme, Erwinia L-asparaginase, occurs as a tetramer which can be dissociated by the stresses of lyophilization into four subunits (subunit M(r) 34 000 Da). Dissociation can be reduced by adding protectants to the formulation to stabilize the biopolymer, while the product should dry to form a pharmaceutically elegant, shelf-stable cake which is readily soluble. Using analytical ultracentrifugation, HPLC, and circular dichroism we have related structural dissociation of the enzyme during lyophilization to biological activity. Additives such as mannitol prevent ablation loss of vial contents and dry to form cosmetically elegant cakes but provide little biological protection, since during freezing they crystallize and are removed from the preparation. Excipients persisting throughout the cycle in the amorphous state provide improved biological protection, although high molecular weight compounds such as Dextran (M(r) 70000 Da) are most effective only during product freezing or storage. Low molecular weight sugars are protective throughout the cycle although formulations containing monosaccharides often exhibit low collapse temperatures (Tc) measured using a freeze-drying microscope or glass transition temperatures (Tg') measured by thermal analysis, but these formulations distort as drying progresses to form a collapsed, cosmetically unacceptable cake, with reduced activity, poor stability, a high moisture content, and reduced solubility. Collapse can be avoided by formulating with disaccharides, which display higher Tc temperatures than monosaccharides, or drying below Tc. Dried samples which persist in the amorphous state can also collapse when stored above their solid-state collapse temperatures when they decay at a faster rate than predicted by Arrhenius kinetics. The solid-state collapse temperature can be significantly decreased by the diffusion of moisture from the stopper into the dry product resulting in an increase in sample water content. Lyophilization cycle times can be reduced by analyzing collapse characteristics so that the relationship between product temperature and chamber pressure can be controlled so that drying rates can be optimized while ensuring that the product does not melt or collapse during sublimation.


Assuntos
Antineoplásicos/química , Asparaginase/química , Erwinia/enzimologia , Asparaginase/administração & dosagem , Liofilização
7.
Br J Cancer ; 72(5): 1096-101, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7577453

RESUMO

Exposure of human cells to gamma-radiation causes levels of the tumour-suppressor nuclear protein p53 to increase in temporal association with the decrease in replicative DNA synthesis. Cells from patients with the radiosensitive and cancer-prone disease ataxia telangiectasia (AT) exhibit radioresistant DNA synthesis and show a reduced or delayed gamma-radiation-induced increase in p53 protein levels. We have used Western immunoblotting with semiquantitative densitometry to examine the gamma-radiation-induced levels of p53 protein in 57 lymphoblastoid cell lines (LCLs) derived from patients with AT, carriers of the AT gene, breast cancer patients and normal donors. We confirm the previously reported reduced induction in AT homozygote LCLs (n = 8) compared with normal donor LCLs (n = 17, P = 0.01). We report that AT heterozygote LCLs (n = 5) also have a significantly reduced p53 induction when compared with LCLs from normal donors (n = 17, P = 0.02). The response of breast cancer patient cells was not significantly different from normal donor cells but 18% (5/27) had a p53 response in the AT heterozygote range (95% confidence interval) compared with only 6% (1/17) of the normal donor cells. We found no significant correlation between p53 induction and cellular radiosensitivity in LCLs from breast cancer patients. These methods may be useful in identifying individuals at greater risk of the DNA-damaging effects of ionising radiation.


Assuntos
Ataxia Telangiectasia/patologia , Linfócitos B/efeitos da radiação , Neoplasias da Mama/patologia , Dano ao DNA , Raios gama , Regulação da Expressão Gênica/efeitos da radiação , Interfase/efeitos da radiação , Proteínas de Neoplasias/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Ataxia Telangiectasia/genética , Linfócitos B/metabolismo , Western Blotting , Neoplasias da Mama/genética , Neoplasias da Mama/radioterapia , Linhagem Celular Transformada , Sobrevivência Celular , Replicação do DNA/efeitos da radiação , DNA de Neoplasias/biossíntese , DNA de Neoplasias/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Herpesvirus Humano 4 , Heterozigoto , Homozigoto , Humanos , Proteínas de Neoplasias/deficiência , Proteínas de Neoplasias/genética , Tolerância a Radiação/genética , Células Tumorais Cultivadas/metabolismo , Células Tumorais Cultivadas/efeitos da radiação , Proteína Supressora de Tumor p53/deficiência , Proteína Supressora de Tumor p53/genética
8.
Br J Cancer ; 72(3): 766-8, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7669591

RESUMO

Piritrexim is a lipid-soluble drug which is as effective an inhibitor of dihydrofolate reductase as methotrexate. Phase I and II studies have indicated activity in some tumour types. Because of its lipophilicity we have conducted a phase II study in recurrent high-grade malignant glioma (grades III and IV). Twenty-seven patients were treated with 25 mg p.o. three times daily for five consecutive days, repeated weekly, with provision for dose escalation or reduction according to toxicity. Five patients received less than 4 weeks' treatment because of disease progression or death. Twenty-two patients were evaluable for response. One complete and one partial response was seen (duration 262+ and 241+ weeks) and 13 patients had static disease for a median duration of 13 weeks (range 7-35). The major toxicity was myelosuppression. This response rate of 9% of evaluable patients is much lower than that seen for some conventionally used drugs and we conclude that piritrexim is unlikely to be of value in the management of high-grade gliomas.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Antagonistas do Ácido Fólico/uso terapêutico , Glioma/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Pirimidinas/uso terapêutico , Administração Oral , Adulto , Idoso , Antineoplásicos/efeitos adversos , Neoplasias Encefálicas/patologia , Esquema de Medicação , Feminino , Antagonistas do Ácido Fólico/efeitos adversos , Glioma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Pirimidinas/efeitos adversos
9.
Int J Radiat Oncol Biol Phys ; 32(5): 1401-7, 1995 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-7635780

RESUMO

PURPOSE: Merkel cell carcinoma (MCC), being a small cell carcinoma, would be expected to be sensitive to radiation. Clinical analysis of patients at our center, especially those with macroscopic disease, would suggest the response is quite variable. We have recently established a number of MCC cell lines from patients prior to radiotherapy, and for the first time are in a position to determine their sensitivity under controlled conditions. METHODS AND MATERIALS: Some of the MCC lines grew as suspension cultures and could not be single cell cloned; therefore, it was not possible to use clonogenic survival for all cell lines. A tetrazolium based (MTT) assay was used for these lines, to estimate cell growth after gamma irradiation. Control experiments were conducted on lymphoblastoid cell lines (LCL) and the adherent MCC line, MCC13, to demonstrate that the two assays were comparable under the conditions used. RESULTS: We have examined cell lines from MCC, small cell lung cancer (SCLC), malignant melanomas, Epstein Barr virus (EBV) transformed lymphocytes (LCL), and skin fibroblasts for their sensitivity to gamma irradiation using both clonogenic cell survival and MTT assays. The results show that the tumor cell lines have a range of sensitivities, with melanoma being more resistant (surviving fraction at 2 Gy (SF2) 0.57 and 0.56) than the small cell carcinoma lines, MCC (SF2 range 0.21-0.45, mean SF2 0.30, n = 8) and SCLC (SF2 0.31). Fibroblasts were the most sensitive (SF2 0.13-0.20, mean 0.16, n = 5). The MTT assay, when compared to clonogenic assay for the MCC13 adherent line and the LCL, gave comparable results under the conditions used. CONCLUSION: Both assays gave a range of SF2 values for the MCC cell lines, suggesting that these cancers would give a heterogeneous response in vivo. The results with the two derivative clones of MCC14 (SF2 for MCC14/1 0.38, MCC14/2 0.45) would further suggest that some of them may develop resistance during clonogenic evolution.


Assuntos
Divisão Celular/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Carcinoma de Célula de Merkel , Linhagem Celular , Relação Dose-Resposta à Radiação , Humanos , Melanoma , Neoplasias Cutâneas , Células Tumorais Cultivadas , Ensaio Tumoral de Célula-Tronco
10.
Radiother Oncol ; 32(3): 210-7, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7816940

RESUMO

The effects of escalating doses of BW12C on normal tissue and tumour blood flow and pO2 in patients were studied. BW12C infusion resulted in a significant reduction in median subcutaneous tissue pO2, and an increase in the proportion of hypoxic values (< or = 2.5 mmHg). In 8 of 9 patients with accessible tumours there was a significant reduction in pO2 during BW12C infusion, but no effect on the proportion of hypoxic values. A rapid decline in normal tissue pO2 in the first 10 min was associated with an increase in skin red cell flux and a reduction of normal subcutaneous tissue, muscle, and tumour red cell flux of 30-50%, that was maintained throughout a subsequent 1-h infusion of BW12C. Tumour perfusion, as measured by dynamic computed tomography, was slightly reduced in five out of six patients studied during BW12C infusion. BW12C reduces both subcutaneous tissue and tumour pO2 in patients. Both haemoglobin modification and reduction in blood flow are probably associated with this effect.


Assuntos
Benzaldeídos/farmacologia , Neoplasias Gastrointestinais/tratamento farmacológico , Músculo Esquelético/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Pele/efeitos dos fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzaldeídos/administração & dosagem , Estudos de Coortes , Eritrócitos/efeitos dos fármacos , Neoplasias Gastrointestinais/irrigação sanguínea , Neoplasias Gastrointestinais/metabolismo , Hemoglobinas/efeitos dos fármacos , Humanos , Hipóxia/sangue , Hipóxia/fisiopatologia , Fluxometria por Laser-Doppler , Mitomicina/administração & dosagem , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Oxigênio/sangue , Oxiemoglobinas/efeitos dos fármacos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Pele/irrigação sanguínea , Pele/metabolismo , Tomografia Computadorizada por Raios X
11.
Cancer Chemother Pharmacol ; 32(1): 67-72, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8462126

RESUMO

The effect of combining the oxygen-transport-modifying drug BW12C with mitomycin C was investigated in a phase 1 study of 26 patients with advanced gastrointestinal cancer. The dose of BW12C was increased from 20 mg/kg to 60 mg/kg. Dose-limiting toxicity of vomiting was experienced at doses greater than 50 mg/kg. This corresponded to whole blood levels > or = 700 micrograms/ml and to > 50% haemoglobin modification. Whole blood concentrations of BW12C and modification of the haemoglobin oxygen saturation curve were linearly dependent on dose. BW12C whole blood pharmacokinetics were best described by a one-compartment model and were clearly dose-dependent. The half-life increased from 2.1 h at a dose of 20 mg/kg to 7.2 h at a dose of 60 mg/kg. The AUC increased in a similar non-linear fashion with increasing dose. Mitomycin C was given at a fixed dose of 20 mg/m2 at the end of the BW12C infusion. Mitomycin C plasma pharmacokinetics fitted a two-compartment model, giving a mean beta half-life of 50 +/- 7 min and AUC of 1.1 +/- 0.08 micrograms/ml h, and were unaffected by the combined treatment. There was no evidence of increased mitomycin C toxicity.


Assuntos
Benzaldeídos/farmacocinética , Neoplasias Gastrointestinais/tratamento farmacológico , Mitomicina/farmacocinética , Benzaldeídos/farmacologia , Combinação de Medicamentos , Avaliação de Medicamentos , Meia-Vida , Humanos , Taxa de Depuração Metabólica , Metástase Neoplásica
13.
Anal Biochem ; 202(2): 331-6, 1992 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-1519760

RESUMO

An enzyme-mediated assay has been developed for the measurement of salicylate using salicylate monooxygenase purified from Pseudomonas cepacia ATCC 29351. Two assay formulations were produced, based on either a multiple-reagent or a single-reagent formulation, to allow sufficient flexibility for automated use. The multiple-reagent formulation was especially suited to diagnostic laboratories performing infrequent manual salicylate estimation where stability of the reconstituted reagent is of paramount importance. This was achieved by preparing the enzyme and color reagents in separate vials, so keeping the enzyme at a stable pH. For more frequent assay use where a reconstituted reagent shelf life was less important, the single-reagent system offers advantages of convenience. However, the working reagent required a pH of 10.0 upon reconstitution. Although the enzyme was sufficiently active at this pH to give a reliable assay, its storage stability was poor at pH 10.0, preventing lyophilization of the reagent at a pH suitable for immediate use on reconstitution. This incompatibility was overcome by use of a layering technique. The enzyme was separated from the buffering solution in the same vial by freezing the buffering solution and then overlayering with the enzyme reagent prior to a second freezing cycle and subsequent freeze drying.


Assuntos
Aspirina/análise , Oxigenases de Função Mista/química , Estabilidade de Medicamentos , Liofilização , Oxigenases de Função Mista/análise
14.
Int J Radiat Oncol Biol Phys ; 22(4): 721-5, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1544845

RESUMO

The effect of combining the oxyhemoglobin-modifying drug BW12C with mitomycin C was investigated in a Phase I study of 18 patients with advanced gastrointestinal cancer. The dose of BW12C was increased from 20 mg/kg to 50 mg/kg to modify the hemoglobin-oxygen saturation curve by up to 48%. The period of maximum modification was then prolonged for up to 3 hr by a maintenance infusion of 4-6 mg/kg/hr. Pharmacokinetics of BW12C and mitomycin C were performed in all patients. Peak levels of BW12C increased from 139 micrograms/ml to 378 micrograms/ml. Plasma half life was independent of dose, with an average of 3.3 hr. BW12C was well tolerated with no severe side effects. Three patients had objective tumour responses.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Benzaldeídos/administração & dosagem , Neoplasias Gastrointestinais/tratamento farmacológico , Mitomicina/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Benzaldeídos/efeitos adversos , Benzaldeídos/farmacocinética , Avaliação de Medicamentos , Hemoglobinas/metabolismo , Humanos , Pessoa de Meia-Idade , Mitomicina/farmacocinética , Oxigênio/sangue
15.
Bioseparation ; 2(6): 375-83, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1281025

RESUMO

Salicylate monooxygenase (EC: 1.14.13.1) has been produced and purified from Pseudomonas cepacia ATCC 29351 which has the ability to utilise salicylate as a sole carbon source. The bacterium was grown on a defined medium containing 2% (w/v) casamino acids and 0.15% (w/v) yeast extract at 25 degrees C; salicylate monooxygenase production was induced by the presence of up to 0.7% (w/v) sodium salicylate, to a level of approximately 2% of the soluble cell protein. The enzyme was purified over 50-fold, with a recovery of about 40%, by a combination of ion exchange and hydrophobic interaction chromatography. The purified enzyme had a specific activity of 14-15 U mg-1 protein and was essentially homogeneous.


Assuntos
Proteínas de Bactérias/isolamento & purificação , Burkholderia cepacia/enzimologia , Oxigenases de Função Mista/isolamento & purificação , Cromatografia por Troca Iônica , Meios de Cultura , Fermentação , Salicilatos/metabolismo , Ácido Salicílico
16.
Int J Cancer ; 47(5): 755-9, 1991 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-2004856

RESUMO

These experiments set out to assess the role of NK and B cells in the resistance of nude mice to human tumor xenotransplantation. The transplantability of 9 fresh and 8 cultured human tumors was compared in 2 strains of mice with different genetic immune deficiencies: athymic NCr/Sed (nu/nu) nude mice, and nude-beige-xid (N:NIH-nu-bg-xid/Sed mice). Flow cytometric studies showed both strains to be deficient in Thy. 1.2 (T) cells and unresponsive to stimulation by Concanavalin A (Con A) or direct T-cell-receptor triggering with anti-CD3. The number of B cells was similar in the 2 strains, but the response to lipopolysaccharide (LPS) was markedly reduced in the nude-beige-xid animals. The number of asialoGM1-positive cells (predominantly NK) detected by flow cytometry was also reduced in the nude-beige-xid mice. The transplantability of the human tumors was found to be equivalent in the 2 strains. Quantitative cell-transplantation assays performed for 2 of the tumor cell lines did not reveal any subtle transplantation advantage for the more broadly immune-deficient animals. No evidence could, therefore, be found to suggest that NK or B cells were major determinants of human tumor xenotransplantability in these strains of mice.


Assuntos
Glioma/imunologia , Camundongos Nus/genética , Neoplasias Experimentais/imunologia , Animais , Linfócitos B/imunologia , Linhagem Celular , Concanavalina A/farmacologia , Citometria de Fluxo , Humanos , Células Matadoras Naturais/imunologia , Lipopolissacarídeos/farmacologia , Camundongos , Transplante de Neoplasias , Transplante Heterólogo/imunologia
17.
Clin Chim Acta ; 187(2): 95-104, 1990 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-2317940

RESUMO

A rapid, enzymatic assay for serum or plasma paracetamol has been developed with the potential for adaptation to a wide range of clinical analysers. The method involves the action of an amidase enzyme to produce 4-aminophenol from paracetamol, which in turn reacts with 8-hydroxyquinoline in the presence of manganese ions to form a blue dye. Two stable reagents are used and excellent precision is achieved over the drug concentration range 0-2.5 mmol/l. The method, which is complete within 6 min, has been validated using a Monarch centrifugal analyser and shows no significant interference from endogenous serum compounds, drugs or paracetamol metabolites.


Assuntos
Acetaminofen/sangue , Amidoidrolases , Autoanálise , Cromatografia Líquida de Alta Pressão , Humanos , Indicadores e Reagentes , Reprodutibilidade dos Testes
18.
Int J Cancer ; 45(2): 325-33, 1990 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-2406204

RESUMO

This study assessed the residual immunity possessed by NCr/Sed (nu/nu) athymic nude mice and examined strategies to reduce it in order to enhance the transplantability of human tumors for experimentation. Adult (8-week-old) female mice had fewer T cells (11%) and more B and NK (asialo-GM1-positive [ASGM1+]) cells in their spleen than euthymic (nu/+) controls. The number of phenotypically mature T cells increased with age, peaking at 16 weeks. ASGM1+ cells also increased in number over time, although the NK-activity decreased after 12 weeks. B cells remained relatively constant in number. Athymic NCr/Sed nude mice displayed reactivity against a human squamous carcinoma xenograph (FaDu), in a Winn's test and TD50 assay. Immunity against xenografts (TD50 assay) was significantly lower (by a factor of 2) in 4-week-old than in 12-week-old nude mice. Similarly, a significant 2-fold reduction in TD50 was obtained after a single intraperitoneal injection of cyclophosphamide into 8-week-old animals. Chronic (greater than 8 weeks) exposure of the nude mice to subcutaneously administered beta-estradiol markedly reduced the number of splenic NK cells and their cytolytic activity, but the TD50 reduction was not statistically significant (p = 0.1). Six Gray whole-body irradiations (WBI) had been shown to produce a highly significant, 3-fold reduction in the TD50 for FaDu. Flow cytometric analysis of splenic lymphoid cells from whole-body-irradiated recipients revealed: (a) marked initial depletion in the absolute numbers of lymphoid cells; (b) marked and long-lasting depletion of T cells, with slow and minimal recovery only evident between 6 and 12 weeks; (c) rapid, almost complete, depletion of B cells with prompt and partial recovery after 2 weeks; (d) depletion of NK cells and NK activity, with recovery by 10 weeks. No change in the number or phagocytic capacity of resident peritoneal macrophages was seen. These data give further support to a postulated role for residual T cells in the xenoreactivity of NCr/Sed nude mice.


Assuntos
Camundongos Nus/imunologia , Transplante Heterólogo , Fatores Etários , Animais , Feminino , Humanos , Terapia de Imunossupressão , Células Matadoras Naturais/fisiologia , Macrófagos/fisiologia , Masculino , Camundongos , Transplante de Neoplasias , Linfócitos T/imunologia , Irradiação Corporal Total
19.
Clin Chem ; 36(1): 131-5, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2297904

RESUMO

This salicylate-specific assay can be adapted for use with most discrete analyzers, for rapid emergency or routine testing with small serum or plasma sample volumes and a single calibration. The basis of this method is as follows: salicylate monooxygenase (EC 1.14.13.1) converts salicylate to catechol in the presence of NADH; the catechol then reacts with 4-aminophenazone under alkaline conditions, catalyzed by manganese ions, to produce a red dye. Incorporation of an NADH-regenerating system, involving glucose and glucose dehydrogenase, into the enzyme reagent ensures that the working reagent is stable for more than two weeks. The standard curve is linear over the drug concentration range 0 to 5 mmol/L. The CV was less than 4% over 20 days. Results correlated well with those by the Trinder colorimetric method and an HPLC method. We saw no interference by any of 80 drugs we tested at therapeutic concentrations or by endogenous compounds in serum.


Assuntos
Oxigenases de Função Mista , Salicilatos/sangue , Autoanálise , Soluções Tampão , Catecóis/análise , Cromatografia Líquida de Alta Pressão , Colorimetria , Emergências , Humanos , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , NAD , Intoxicação/sangue , Salicilatos/toxicidade , Tensoativos
20.
Vet Microbiol ; 21(1): 41-55, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2623796

RESUMO

Four Mycoplasma arthritidis strains were examined for differences in virulence for LEW rats and elicitation of antibody responses in the immunoglobulin (Ig) M and G classes and in the four IgG subclasses. Two strains were highly arthritogenic and two were relatively avirulent. When the latter strains did induce arthritis, it was significantly less severe (P less than 0.05) and developed significantly later (P less than 0.001) than in rats injected with the two virulent strains, suggesting that the low-virulence organisms are able to persist asymptomatically in rats for several weeks. None of the M. arthritidis-injected rats developed metabolism-inhibiting (MI) antibodies at any time during the 6-week observation period. Responses to other M. arthritidis antigens from all four strains were measured by enzyme immunoassay (ELISA); they were similar qualitatively but differed quantitatively. Rats injected with the two avirulent strains showed significantly lower titers of IgM antibodies (P less than 0.01) throughout the 6-week observation period and significantly lower early titers of IgG antibodies (P less than 0.05) than rats injected with the two virulent strains. In addition, peak IgM antibody titers, IgM titers measured 1 and 6 weeks after injection and IgG antibody titers measured 1 week after injection all correlated significantly with peak arthritis scores (P less than 0.05). The IgG antibody response against all four strains appeared mostly in the IgG2a and IgG2b fractions, with very little in the IgG1 and IgG2c fractions. Using immunoblotting, the immunodominant antigens of the two virulent strains appeared very similar, but the avirulent strains differed slightly from each other and from the other two. This study indicates that immune responses of rats to virulent and avirulent strains are similar but not identical and that immunogenicity for LEW rats may be a strain-specific characteristic for M. arthritidis.


Assuntos
Anticorpos Antibacterianos/biossíntese , Artrite/veterinária , Mycoplasma/imunologia , Ratos Endogâmicos Lew/microbiologia , Ratos Endogâmicos/microbiologia , Animais , Artrite/imunologia , Artrite/microbiologia , Proteínas Sanguíneas/imunologia , Ensaio de Imunoadsorção Enzimática , Immunoblotting , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Mycoplasma/isolamento & purificação , Mycoplasma/patogenicidade , Ratos , Virulência
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