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1.
Br J Dermatol ; 164(3): 633-6, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21375515

RESUMEN

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.


Asunto(s)
Carcinoma in Situ/tratamiento farmacológico , Carcinoma Basocelular/tratamiento farmacológico , Carcinoma de Células Escamosas/tratamiento farmacológico , Euphorbiaceae , Extractos Vegetales/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Administración Tópica , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma in Situ/patología , Carcinoma Basocelular/patología , Carcinoma de Células Escamosas/patología , Estudios de Cohortes , Humanos , Persona de Mediana Edad , Fitoterapia/métodos , Neoplasias Cutáneas/patología
2.
Cancer Res ; 48(22): 6510-6, 1988 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-3052803

RESUMEN

The transplantability of experimental tumors into the brain (i.c.) and s.c. tissues of C3Hf/Sed and athymic NCr/Sed nude mice was examined using quantitative cell transplantation assays. Studies using the immune-competent C3H animals showed that brain is a more favorable site for the transplantation of syngeneic tumor than s.c. tissue and that this is true for nonimmunogenic as well as immunogenic tumors. The capacity of the brain to act as an immunological sanctuary can be overwhelmed by a strong, systemic, secondary immune response such as that evoked by the methylcholanthrene-induced sarcoma FSal. In studies performed using NCr/Sed nude mice, the allogeneic tumor MCaIV was found not to be demonstrably immunogenic. The cell dose required to transplant the tumor into 50% of recipients (TD50) could neither be increased by immunization procedures nor decreased by six Gy whole-body irradiation (WBI) prior to transplantation. Delayed-type hypersensitivity to this tumor was not expressed by nude mice after rechallenge with tumor antigen. The TD50 was again lower for i.c. than s.c. transplantation and the ratio s.c./i.c. was comparable to that found in syngeneic C3Hf/Sed hosts. Three human tumors have been similarly tested. They were: FaDu, a pharyngeal squamous carcinoma; HFSal, a fibrosarcoma; and U87, a malignant glioma. s.c. TD50 values were in all cases significantly higher than those obtained i.c. The ratios TD50 s.c./i.c. ranged from 6.4 to greater than 50 in five studies, substantially higher than those found for transplantation of murine tumors into either the syngeneic or the allogeneic recipients. Six Gy WBI reduced the s.c. TD50 for these tumors, but in each case the value remained significantly higher than that obtained i.c. 19.4 Gy WBI given in 10 equal fractions and followed by i.v. bone marrow rescue reduced further the s.c. TD50 for FaDu. NCr/Sed nude mice demonstrated cross-reacting delayed-type hypersensitivity against FaDu and HFSal. A small proportion of FaDu tumors (less than 2%) displayed a spontaneous halt in growth or even regression. When the host cell infiltrate of these tumors was analyzed, an increase was seen in the proportion of Thy 1.2 and asialo-GM1-positive cells as compared with progressively growing tumors. These data strongly suggest that a residual low level of immune reactivity exists in nude mice against xenotransplanted human tumors. This resistance to s.c. transplantation may be diminished by WBI and is less for intracerebral implantation.


Asunto(s)
Neoplasias Encefálicas/patología , Trasplante de Neoplasias , Neoplasias Cutáneas/patología , Animales , Antígenos de Neoplasias/inmunología , Humanos , Hipersensibilidad Tardía , Inmunización , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Desnudos , Linfocitos T/inmunología , Trasplante Heterólogo , Irradiación Corporal Total
3.
Clin Oncol (R Coll Radiol) ; 17(5): 332-6, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16097563

RESUMEN

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.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/radioterapia , Desoxicitidina/análogos & derivados , Desoxicitidina/administración & dosificación , Neoplasias Pulmonares/radioterapia , Adulto , Anciano , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neumonitis por Radiación/etiología , Radioterapia/efectos adversos , Dosificación Radioterapéutica , Factores de Tiempo , Gemcitabina
4.
Hum Mutat ; 17(1): 75-6, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11139252

RESUMEN

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.


Asunto(s)
Ataxia Telangiectasia/genética , Conservación de la Sangre/métodos , Exones/genética , Proteínas Serina-Treonina Quinasas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Eliminación de Secuencia , Empalme Alternativo , Proteínas de la Ataxia Telangiectasia Mutada , Neoplasias de la Mama/sangre , Neoplasias de la Mama/genética , Neoplasias de la Mama/radioterapia , Proteínas de Ciclo Celular , Línea Celular Transformada , Análisis Mutacional de ADN , Proteínas de Unión al ADN , Humanos , Proteínas Serina-Treonina Quinasas/sangre , Transcripción Genética , Proteínas Supresoras de Tumor
5.
Int J Radiat Oncol Biol Phys ; 32(5): 1401-7, 1995 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-7635780

RESUMEN

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.


Asunto(s)
División Celular/efectos de la radiación , Supervivencia Celular/efectos de la radiación , Carcinoma de Células de Merkel , Línea Celular , Relación Dosis-Respuesta en la Radiación , Humanos , Melanoma , Neoplasias Cutáneas , Células Tumorales Cultivadas , Ensayo de Tumor de Célula Madre
6.
Int J Radiat Oncol Biol Phys ; 22(4): 721-5, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1544845

RESUMEN

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.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Benzaldehídos/administración & dosificación , Neoplasias Gastrointestinales/tratamiento farmacológico , Mitomicina/administración & dosificación , Adulto , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Benzaldehídos/efectos adversos , Benzaldehídos/farmacocinética , Evaluación de Medicamentos , Hemoglobinas/metabolismo , Humanos , Persona de Mediana Edad , Mitomicina/farmacocinética , Oxígeno/sangre
7.
Radiother Oncol ; 32(3): 210-7, 1994 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7816940

RESUMEN

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.


Asunto(s)
Benzaldehídos/farmacología , Neoplasias Gastrointestinales/tratamiento farmacológico , Músculo Esquelético/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Piel/efectos de los fármacos , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Benzaldehídos/administración & dosificación , Estudios de Cohortes , Eritrocitos/efectos de los fármacos , Neoplasias Gastrointestinales/irrigación sanguínea , Neoplasias Gastrointestinales/metabolismo , Hemoglobinas/efectos de los fármacos , Humanos , Hipoxia/sangre , Hipoxia/fisiopatología , Flujometría por Láser-Doppler , Mitomicina/administración & dosificación , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/metabolismo , Oxígeno/sangre , Oxihemoglobinas/efectos de los fármacos , Flujo Sanguíneo Regional/efectos de los fármacos , Piel/irrigación sanguínea , Piel/metabolismo , Tomografía Computarizada por Rayos X
8.
Cancer Chemother Pharmacol ; 32(1): 67-72, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8462126

RESUMEN

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.


Asunto(s)
Benzaldehídos/farmacocinética , Neoplasias Gastrointestinales/tratamiento farmacológico , Mitomicina/farmacocinética , Benzaldehídos/farmacología , Combinación de Medicamentos , Evaluación de Medicamentos , Semivida , Humanos , Tasa de Depuración Metabólica , Metástasis de la Neoplasia
9.
Clin Chim Acta ; 155(3): 209-19, 1986 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-3708854

RESUMEN

A novel enzymatic assay for salicylate in serum has been developed. Salicylate monooxygenase and NADH are used to convert the drug to catechol. This is reacted with 4-aminophenol at high pH to yield a blue product, which is detected colorimetrically. The assay is complete in less than seven minutes and requires no sophisticated equipment. The method is precise, sensitive and shows excellent accuracy in recovery experiments and when compared to a high performance liquid chromatography method. The assay is free from interference by coloured or turbid samples, salicylate metabolites, structurally related compounds such as benzoate and 4-hydroxybenzoate, and a range of drugs. The assay reagents demonstrate excellent stability. The formulation of the assay in two stages provides increased specificity and sensitivity compared to other emergency salicylate assays and allows the inclusion of reagents to greatly enhance the stability of the salicylate monooxygenase-NADH reagent, yet the method is simple and performs well.


Asunto(s)
Oxigenasas de Función Mixta , Salicilatos/análisis , Tampones (Química) , Catecoles/análisis , Colorimetría , Hemólisis , Humanos , Indicadores y Reactivos , Ictericia/sangre , Cinética , Lípidos/sangre , NAD , Salicilatos/sangre
10.
Clin Chim Acta ; 187(2): 95-104, 1990 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-2317940

RESUMEN

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.


Asunto(s)
Acetaminofén/sangre , Amidohidrolasas , Autoanálisis , Cromatografía Líquida de Alta Presión , Humanos , Indicadores y Reactivos , Reproducibilidad de los Resultados
11.
Vet Microbiol ; 21(1): 41-55, 1989 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-2623796

RESUMEN

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.


Asunto(s)
Anticuerpos Antibacterianos/biosíntesis , Artritis/veterinaria , Mycoplasma/inmunología , Ratas Endogámicas Lew/microbiología , Ratas Endogámicas/microbiología , Animales , Artritis/inmunología , Artritis/microbiología , Proteínas Sanguíneas/inmunología , Ensayo de Inmunoadsorción Enzimática , Immunoblotting , Inmunoglobulina G/inmunología , Inmunoglobulina M/inmunología , Mycoplasma/aislamiento & purificación , Mycoplasma/patogenicidad , Ratas , Virulencia
12.
Vet Microbiol ; 17(1): 45-57, 1988 May.
Artículo en Inglés | MEDLINE | ID: mdl-3262951

RESUMEN

Sera from rats convalescing from infection with Mycoplasma arthritidis were tested for their ability to react with M. arthritidis membrane antigens by immunoblotting and radioimmunoprecipitation. The absence of metabolism-inhibition (MI) antibody activity in these sera suggested that rats might fail to recognize those membrane antigens involved in eliciting MI antibodies therefore rabbit antisera, which are strongly MI positive for M. arthritidis, were used for comparison. Antigenic recognition patterns of M. arthritidis surface and membrane antigens were not identical for rats and rabbits. The most striking and reproducible difference was the failure of rats to produce IgG antibodies against a surface antigen migrating in the 47,000-50,000 molecular weight range on SDS-polyacrylamide gels. However, rats recognized at least 2 antigens which we had previously shown to be "MI antigens", therefore the inability to express MI antibodies probably cannot be explained by their inability to recognize M. arthritidis "MI antigens".


Asunto(s)
Antígenos Bacterianos/inmunología , Artritis Infecciosa/inmunología , Infecciones por Mycoplasma/inmunología , Mycoplasma/inmunología , Animales , Antígenos de Superficie/inmunología , Autorradiografía , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Femenino , Sueros Inmunes/inmunología , Immunoblotting , Masculino , Pruebas de Precipitina , Conejos , Ratas , Ratas Endogámicas Lew
13.
J Pharm Sci ; 85(12): 1301-5, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8961143

RESUMEN

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.


Asunto(s)
Antineoplásicos/química , Asparaginasa/química , Erwinia/enzimología , Asparaginasa/administración & dosificación , Liofilización
17.
Br Dent J ; 203(10): 601-5, 2007 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-18037853

RESUMEN

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.


Asunto(s)
Ergonomía/instrumentación , Enfermedades Musculoesqueléticas/prevención & control , Enfermedades Profesionales/prevención & control , Postura , Estudiantes de Odontología , Extremidad Superior/fisiología , Equipo Dental , Diseño de Equipo , Humanos , Proyectos Piloto , Postura/fisiología , Estadísticas no Paramétricas
18.
Br J Cancer ; 72(5): 1096-101, 1995 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7577453

RESUMEN

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.


Asunto(s)
Ataxia Telangiectasia/patología , Linfocitos B/efectos de la radiación , Neoplasias de la Mama/patología , Daño del ADN , Rayos gamma , Regulación de la Expresión Génica/efectos de la radiación , Interfase/efectos de la radiación , Proteínas de Neoplasias/biosíntesis , Proteína p53 Supresora de Tumor/biosíntesis , Ataxia Telangiectasia/genética , Linfocitos B/metabolismo , Western Blotting , Neoplasias de la Mama/genética , Neoplasias de la Mama/radioterapia , Línea Celular Transformada , Supervivencia Celular , Replicación del ADN/efectos de la radiación , ADN de Neoplasias/biosíntesis , ADN de Neoplasias/efectos de la radiación , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Herpesvirus Humano 4 , Heterocigoto , Homocigoto , Humanos , Proteínas de Neoplasias/deficiencia , Proteínas de Neoplasias/genética , Tolerancia a Radiación/genética , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/efectos de la radiación , Proteína p53 Supresora de Tumor/deficiencia , Proteína p53 Supresora de Tumor/genética
19.
Clin Rehabil ; 15(3): 324-30, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11386404

RESUMEN

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.


Asunto(s)
Brazo/fisiología , Baile/fisiología , Postura/fisiología , Propiocepción/fisiología , Adulto , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados
20.
Bioseparation ; 2(6): 375-83, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1281025

RESUMEN

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.


Asunto(s)
Proteínas Bacterianas/aislamiento & purificación , Burkholderia cepacia/enzimología , Oxigenasas de Función Mixta/aislamiento & purificación , Cromatografía por Intercambio Iónico , Medios de Cultivo , Fermentación , Salicilatos/metabolismo , Ácido Salicílico
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