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1.
Int J Oral Maxillofac Surg ; 52(2): 219-226, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35760661

RESUMO

The oral cavity is densely populated with microorganisms. As a result, intraoral surgical sites are prone to contamination by pathogens, potentially triggering surgical site infections (SSIs). Prophylactic antibiotics have proven beneficial in reducing the rate of SSIs. However, no consensus has been reached regarding the most effective regimen. The purpose of this study was to investigate two different antibiotic regimens - single-dose and prolonged antibiotic prophylaxis - regarding the rate and severity of postoperative SSIs in patients undergoing orthognathic surgery. Data were analysed retrospectively. Patients who underwent bilateral sagittal split ramus osteotomy or bimaxillary surgery in the study department in 2017 were screened for eligibility. Ninety-nine patients were included in the study and were divided into two groups. The prolonged-antibiotic prophylaxis group (PAP; n = 49) received a 5-day antibiotic prophylaxis regimen, while the single-dose antibiotic prophylaxis group (SDAP; n = 50) received single-dose antibiotic prophylaxis. The groups were assessed for the rate and severity of SSIs following orthognathic surgery. Five patients (10.2%) in the PAP group and seven (14%) in the SDAP group developed infections; no statistically significant difference in the occurrence of SSIs was found (P = 0.380). Single-dose antibiotic prophylaxis is as effective as a 5-day antibiotic prophylaxis regimen in preventing SSIs in orthognathic surgery and is a suitable antibiotic prophylaxis option when considering the risk of antibiotic resistance.


Assuntos
Cirurgia Ortognática , Infecção da Ferida Cirúrgica , Humanos , Infecção da Ferida Cirúrgica/epidemiologia , Antibioticoprofilaxia , Estudos Retrospectivos , Antibacterianos/uso terapêutico
2.
Int J Oral Maxillofac Surg ; 51(4): 493-500, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34426056

RESUMO

The amount of blood loss determined in orthognathic surgery differs greatly among studies. This can be attributed to the inhomogeneity in study cohorts analysed, but may also be a result of the varying methodologies used for blood loss determination. However, this has yet to be explored. Thus, the aim of this study was to investigate the extent to which the formula and time point used to measure blood loss affect the blood loss volume, determined in a homogeneous cohort undergoing bimaxillary surgery. Blood loss was calculated at 24 and 48 hours postoperatively using the haemoglobin balance method and the formula of Hurle et al. The estimated total blood volume was established based on the formulae of Nadler et al. and Choi et al. Differences in blood loss volume with respect to time point and formula were analysed and compared. Fifty-four patients were included in the final analysis. Statistically significant differences in blood loss were observed: a significant increase in the blood loss volume from 24 hours to 48 hours postoperatively was detected. When comparing the formulae used, blood loss differed significantly at 24 hours after surgery; however no such difference resulted at 48 hours postoperatively. These findings imply that the time point of measuring blood loss is highly relevant, whereas the formulae applied seem to have less of an impact on the blood loss volumes calculated.


Assuntos
Cirurgia Ortognática , Procedimentos Cirúrgicos Ortognáticos , Perda Sanguínea Cirúrgica , Humanos , Procedimentos Cirúrgicos Ortognáticos/métodos
3.
Int J Oral Maxillofac Surg ; 49(6): 726-733, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31699632

RESUMO

Patient dissatisfaction with labial appearance in the adult cleft lip is frequently linked to poor upper lip projection. Other areas of concern include asymmetry and impaired upper lip height. Different surgical techniques are available to address volumetric deficiencies, according to extent and localization. However, data comparing outcomes in these different areas are limited. The main aim of this study was to assess the relative gains in upper lip projection. An evaluation of upper vermilion height and symmetry was also performed. Thirty-seven consecutive patients treated by a single surgeon had their pre- and postoperative results measured using standardized photographs; these were analysed using subjective and objective outcome measures. Seven examiners evaluated anonymized pre- and postoperative side and front views for subjective evaluation. The objective analysis was performed using Adobe Photoshop. Fifteen lip revisions, four Abbe flaps, 12 dermal grafts, and six PermaLip implants were performed. In bilateral cleft lip and palate patients, Abbe flaps showed the most significant improvement in labial projection, followed by PermaLip implants and dermal grafts. In unilateral cleft lip and palate patients, PermaLip implants best addressed impaired lip projection, followed by dermal grafts. Overall, functional lip revisions showed excellent outcomes for upper lip symmetry; however, only minor changes in labial projection were found.


Assuntos
Fenda Labial/cirurgia , Procedimentos de Cirurgia Plástica , Adulto , Humanos , Mucosa Bucal , Reoperação , Transplante de Pele , Retalhos Cirúrgicos
4.
Int J Oral Maxillofac Surg ; 47(10): 1281-1287, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29703666

RESUMO

Orbital tumours, located in the medial extraconal and intraconal compartment of the orbit, represent a challenge, with regard to surgical exposure. In the present paper removal of a cavernous haemangioma, located in the medial intraconal compartment was accomplished by combining lateral orbitotomy, midfacial degloving and LeFort-I osteotomy. Resection of the tumour could be performed under direct vision. Surgical exposure and removal of the lesion were obtained, without causing damage to surrounding tissues. Aesthetical results and postoperative eye function proved to be highly satisfactorily. With regard to limitations, concerning the combination of these methods, extended surgery duration and invasiveness have to be named. According to the technical feasibility and postoperative results, this new surgical approach represents a reliable and fully viable alternative method for the removal of medial orbital tumours.


Assuntos
Craniotomia/métodos , Hemangioma Cavernoso/diagnóstico por imagem , Hemangioma Cavernoso/cirurgia , Neoplasias Orbitárias/diagnóstico por imagem , Neoplasias Orbitárias/cirurgia , Osteotomia de Le Fort , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade
5.
Endosc Int Open ; 5(7): E580-E586, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28670614

RESUMO

BACKGROUND AND AIM: Removal of polyps during colonoscopy effectively prevents the development of colorectal cancer. So far, snare resection with high frequency current with or without prior submucosal saline injection is the method of choice. The aim of this study was to evaluate the feasibility, safety, and outcome of cold snare resection during routine endoscopy. METHODS: In this prospective study, 522 patients undergoing outpatient colonoscopy were included. Cold snare resection for diminutive (< 6 mm), small (6 - 9 mm), and larger polyps (> 9 - 15 mm) was performed using a dedicated cold snare device (Exacto ® ) without prior submucosal injection. Outcome parameters included bleeding rate, perforation rate, procedure time, histologic evaluation of polyp margins, and success rates. The data were compared to a group of patients undergoing hot snare resection. RESULTS: Overall, 1233 polyps were removed using cold snare resection with an overall success rate of 99.4 %. All failures of cold snare resection occurred in the cecum (8/82, failure rate 9.8 %). In the remaining colon, the success rate was 100 %. Immediate post-polypectomy bleeding occurred in 0.49 % of all patients and was most frequently seen in polyps larger than 9 mm. The procedure time was significantly shorter using cold snare resection compared with hot snare resection (27.6 min vs. 35.7 min, P  < 0.01). CONCLUSION: Cold snare resection can be performed safely in outpatients for removal of small polyps in screening colonoscopy. It does not require prior saline injection and reduces procedure time without an increased risk of bleeding.

6.
Schmerz ; 31(4): 375-382, 2017 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-27975118

RESUMO

BACKGROUND: Providing end of life care for dying patients and those with life-threatening diseases is one of the core competences of physician. During the course of training all physicians should develop a sharpened perception of symptoms and acquire competence in the relief and therapy of pain. OBJECTIVES: The Hospital of Saint John of God in Vienna, Austria, provides an educational program for residents concerning end of life care. Treatment of pain is one of the major topics. A questionnaire (PKT) was designed in order to evaluate the efficiency of this program. MATERIAL AND METHODS: The Japanese PEACE questionnaire for assessing palliative knowledge of physicians was translated into German and the items checking specific self-efficacy expectations in palliative care in the Bonn palliative knowledge test (Bonner Palliativwissenstests) were transformed into physician duties. The new combination of 52 items was validated by testing groups of physicians with different levels of palliative education and experience. RESULTS: The 37 physicians who had received palliative education scored better in the knowledge section than the 46 without palliative education: 21 vs. 16 correct answers out of 28 (p < 0.001). In these two groups we also found a differences in self-efficacy expectations in palliative care: 46 vs. 35 points out of 54 (p < 0.001). Having worked in a specialized palliative setting (n = 33) was associated with higher scores in palliative knowledge 23 vs. 16 points (p < 0.001) as well as in self-efficacy expectations 47 vs. 35 (p < 0.001). CONCLUSION: The PKT is a German questionnaire that was validated to assess the efficiency of palliative education for physicians.


Assuntos
Competência Clínica , Educação Médica , Avaliação Educacional , Cuidados Paliativos/psicologia , Papel do Médico/psicologia , Autoeficácia , Inquéritos e Questionários , Áustria , Comparação Transcultural , Currículo , Humanos , Psicometria , Reprodutibilidade dos Testes , Tradução
7.
Med Klin Intensivmed Notfmed ; 109(1): 13-8, 2014 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-24352620

RESUMO

Modern intensive care is responsible both for curative interventions in critical health situations and palliative terminal care for the dying ICU patient. By applying an integrated ethics approach, this article examines organizational and cultural factors shaping good terminal care in the ICU. Starting with a reflection on what it means to be human, ethical goals for care of the dying are formulated. Among them, the article focuses on practices ensuring a dignified dying process, on the structured engagement of patients' families, on respecting cultural and spiritual values, and on a clinical pathway for terminal care as an institutional framework. In conclusion, it becomes evident that good terminal care in the ICU not only depends on ethically sound decisions on withholding or withdrawing medical interventions but also on organizational and cultural aspects which must be acknowledged and shaped.


Assuntos
Ética Médica , Unidades de Terapia Intensiva/ética , Cuidados Paliativos/ética , Assistência Terminal/ética , Procedimentos Clínicos/ética , Competência Cultural , Alemanha , Humanos , Planejamento de Assistência ao Paciente , Relações Profissional-Família , Direito a Morrer/ética , Espiritualidade
8.
Int J Oral Maxillofac Surg ; 42(3): 321-5, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23092854

RESUMO

Surgically assisted rapid maxillary expansion (SARME) is commonly used to correct maxillary transverse deficiency. The aim of this study was to analyse the need for intraoperative liberation of the nasal septum during the procedure. SARME was performed in 25 patients by combining a lateral osteotomy with an inter-radicular maxillary osteotomy. The deviation of the nasal septum after SARME was evaluated by comparing measurements between radiologically defined landmarks on pre- and postoperative computed tomographic images. Two defined angles (angle I, between crista galli-symphysis mandibulae and crista galli-septum nasi; angle II, between maxillary plane and septum nasi) were measured based on four representative planes and septal movement was analysed. The mean changes in angles I (0.03° ± 0.78°) and II (0.25° ± 1.04°) did not differ significantly from zero (p=0.87 and p=0.24, respectively). Observed variations and displacements were considered to be acceptable because they were insignificant in every respect. Intranasal airway function was also examined pre- and postoperatively to evaluate any loss of ventilation. The described surgical technique is a successful method of maxillary segment distraction. The authors found no compelling reason to release the nasal septum in the context of SARME.


Assuntos
Má Oclusão/cirurgia , Osteotomia Maxilar/métodos , Septo Nasal/cirurgia , Ortodontia Corretiva/métodos , Técnica de Expansão Palatina , Adolescente , Adulto , Remodelação das Vias Aéreas , Feminino , Humanos , Masculino , Osteotomia Maxilar/instrumentação , Ortodontia Corretiva/instrumentação , Procedimentos Cirúrgicos Ortognáticos/instrumentação , Procedimentos Cirúrgicos Ortognáticos/métodos , Técnica de Expansão Palatina/instrumentação , Estudos Retrospectivos , Fatores de Tempo
9.
Rev Sci Instrum ; 81(2): 02A328, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20192349

RESUMO

The MedAustron Ion therapy center will be constructed in Wiener Neustadt (Austria) in the vicinity of Vienna. Its accelerator complex consists of four ion sources, a linear accelerator, a synchrotron, and a beam delivery system to the three medical treatment rooms and to the research irradiation room. The ion sources shall deliver beams of H(3)(1+), C(4+), and light ions with utmost reliability and stability. This paper describes the features of the ion sources presently planned for the MedAustron facility, such as ion source main parameters, gas injection, temperature control, and cooling systems. A dedicated beam diagnostics technique is proposed in order to characterize electron cyclotron resonance (ECR) ion beams; in the first drift region after the ion source, a fraction of the mixed beam is selected via moveable aperture. With standard beam diagnostics, we then aim to produce position-dependant observables such as ion-current density, beam energy distribution, and emittance for each charge states to be compared to simulations of ECR e-heating, plasma simulation, beam formation, and transport.


Assuntos
Radioterapia/instrumentação , Carbono , Luz , Fenômenos Mecânicos , Modelos Teóricos , Prótons , Radioterapia/métodos , Reprodutibilidade dos Testes , Temperatura
10.
Eur J Cancer ; 33(9): 1516-8, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9337699

RESUMO

Because P-glycoprotein expression might be associated with a more aggressive behaviour of colorectal carcinomas (Weinstein et al., Cancer Res, 1991, 51, 2720-2726), we determined the relationship between MDR1 RNA expression of the carcinomas and the survival of the patients. At a median duration of follow-up of 86 months, event-free survival of patients with MDR1 RNA-negative tumours (n = 35) was not significantly different to that of patients with MDR1 RNA positive tumours (n = 67). Among the different tumour stages, event-free survival of the patients was also independent of MDR1 gene expression of the tumours. Thus, these findings do not support the hypothesis that local aggressiveness of P-glycoprotein positive tumour cells translates into worse clinical outcome.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/metabolismo , Proteínas de Neoplasias/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Seguimentos , Expressão Gênica , Genes MDR , Humanos , Proteínas de Neoplasias/genética , Prognóstico , RNA Neoplásico/genética , Taxa de Sobrevida
11.
Anticancer Res ; 14(3B): 1293-5, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7915092

RESUMO

The expression of the MDR1 gene, a multidrug resistance gene, was determined in patients (N = 24) with myelodysplastic syndrome or acute myeloid leukemia evolving from it. MDR1 RNA expression of the mononuclear cells was detected in 14 (58%) patients. Among patients who had progressed to acute myeloid leukemia (sAML) (N = 14), MDR1 RNA expression was seen in 8 (57%) patients. Expression was observed in the 2 patients who had been pretreated with MDR drugs. These findings indicate that the MDR1 gene is frequently expressed in MDS or sAML and suggest that multidrug resistance might be involved in the clinical drug resistance of these diseases.


Assuntos
Proteínas de Transporte/genética , Resistência a Medicamentos/genética , Leucemia Mieloide Aguda/genética , Glicoproteínas de Membrana/genética , Síndromes Mielodisplásicas/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Expressão Gênica , Humanos , Leucemia Mieloide Aguda/etiologia , Masculino , Pessoa de Meia-Idade
12.
Leuk Lymphoma ; 13(3-4): 333-8, 1994 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7914128

RESUMO

In order to assess the clinical role of the MDR1 gene in chronic lymphocytic leukemia (CLL), we determined its expression in the leukemic cells of 39 patients with CLL and compared this with other clinical and laboratory parameters. MDR1 RNA expression was detected in 29 patients. MDR1 RNA transcripts were independent of age, treatment status of the patients and the clinical stage of CLL, but correlated with the white blood cell count and MDR2 RNA transcripts. Expression of the tumor suppressor gene p53 was found in 30 out of 37 patients and was associated with MDR1 RNA expression (P < 0.001). Immunocytochemistry using the monoclonal antibody C219 was performed in 38 patients, and in 28 cases, more than 5% of the leukemic cells were found to express cell surface P-glycoprotein. P-glycoprotein expression correlated with the expression of MDR1 RNA (P = 0.048).


Assuntos
Proteínas de Transporte/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Linfocítica Crônica de Células B/genética , Glicoproteínas de Membrana/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Corticosteroides/administração & dosagem , Corticosteroides/farmacologia , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Proteínas de Transporte/biossíntese , Clorambucila/administração & dosagem , Clorambucila/farmacologia , Ciclofosfamida/administração & dosagem , Ciclofosfamida/análogos & derivados , Ciclofosfamida/farmacologia , Feminino , Genes p53 , Humanos , Técnicas Imunoenzimáticas , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/patologia , Masculino , Glicoproteínas de Membrana/biossíntese , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prednisona/farmacologia , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , RNA Neoplásico/biossíntese , RNA Neoplásico/genética , Vincristina/administração & dosagem , Vincristina/farmacologia
13.
Am J Physiol ; 266(1 Pt 2): H121-7, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8304492

RESUMO

Because of its potential importance in injury during myocardial ischemia and reperfusion, we assessed mechanisms of hydrogen peroxide (H2O2) cytotoxicity in cultured chick embryo cardiac myocytes. Injury was quantitated by release of lactate dehydrogenase (LDH) or 51Cr, both of which correlated with loss of cell viability assessed by trypan blue exclusion. The iron chelator deferoxamine (0.25-2 mM), but not equimolar iron-loaded deferoxamine, markedly reduced LDH and 51Cr release. Injury was also prevented or attenuated by the diffusible reactive oxygen metabolite scavengers dimethylthiourea (10-20 mM) and N-(2-mercaptopropionyl)-glycine (20 mM). The hydroxyl radical scavenger, dimethyl sulfoxide (200-400 mM), also reduced injury. Other scavengers that probably remained extracellular, superoxide dismutase and mannitol, were ineffective. Thus, with exposure of cardiac myocytes to H2O2, cytotoxicity requires reactions catalyzed by intracellular iron.


Assuntos
Coração/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Ferro/fisiologia , Animais , Sobrevivência Celular , Sistema Livre de Células , Células Cultivadas , Embrião de Galinha , Difusão , Dimetil Sulfóxido/farmacologia , Sequestradores de Radicais Livres , Miocárdio/citologia , Espécies Reativas de Oxigênio/metabolismo , Tioureia/análogos & derivados , Tioureia/farmacologia , Tiopronina/farmacologia
14.
Br J Cancer ; 68(4): 691-4, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8398695

RESUMO

The expression of the MDR1 gene, a multidrug resistance gene, was prospectively determined in 113 primary colorectal carcinoma specimens and correlated with clinical data including survival durations of the patients. MDR1 RNA was detected in 65% of the carcinomas. No expression of the MDR2 gene was seen, MDR1 gene expression was independent of age and sex of the patients, size and histologic grading of the tumour, lymph node involvement and distant metastasis. Kaplan-Meier analysis revealed that the durations of both relapse-free survival and overall survival were not different between patients with MDR1 RNA positive tumours and those with MDR1 RNA negative tumours.


Assuntos
Adenocarcinoma/química , Neoplasias do Colo/química , Resistência a Medicamentos/genética , RNA Neoplásico/análise , Neoplasias Retais/química , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Colo/genética , Neoplasias do Colo/mortalidade , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias Retais/genética , Neoplasias Retais/mortalidade , Análise de Sobrevida
15.
Cancer ; 71(3): 667-71, 1993 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-8431845

RESUMO

BACKGROUND: Drug resistance remains a major problem in gastric carcinomas. To evaluate the mechanisms involved in this resistance, the authors determined the expression of the MDR1 gene, a multidrug resistance gene, in primary gastric carcinomas. METHODS: MDR1 RNA levels of gastric carcinoma specimens (n = 22) were determined by slot blot analysis. An MDR1 cDNA (probe 5A) was used for the hybridization. RESULTS: MDR1 RNA was detected in 41% of the gastric carcinomas, with high levels in 18% of the specimens. No expression of the MDR3 gene was observed in these tumors. MDR1 gene expression was independent of patient age, tumor localization, and lymph node involvement. However, MDR1 RNA expression was less frequent in locally advanced tumors and was absent in the primary tumors of all six patients who had distant metastases. CONCLUSIONS: The data indicate that multidrug-resistant cells are present in primary gastric carcinomas and suggest that multidrug resistance might contribute to the clinical drug resistance of these tumors.


Assuntos
Adenocarcinoma/genética , Resistência a Medicamentos/genética , Expressão Gênica/fisiologia , Neoplasias Gástricas/genética , Feminino , Humanos , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias Gástricas/patologia
17.
Metabolism ; 41(1): 56-63, 1992 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-1311403

RESUMO

We have examined the effects of diabetes, fasting, and refeeding on Na+/K(+)-adenosine triphosphatase (ATPase) activity and its catalytic alpha II subunit gene expression in skeletal muscle. Two hypoinsulinemic states, streptozotocin-induced diabetes and 48-hour fasting caused a significant decrease (P less than .05) in skeletal muscle Na+/K(+)-ATPase activity and a marked increase (P less than .01) in the levels of alpha II subunit mRNA. A decrease in enzyme activity was observed on the 2nd and the 14th day of diabetes, whereas an increase in alpha II mRNA levels was found only on the 14th day. The levels of alpha I mRNA were not affected, while the levels of mRNA of the structural beta subunit were decreased on the 14th day of diabetes. Correction of hyperglycemia with insulin restored enzyme activity and alpha II isoform mRNA levels toward normal in diabetic animals. Refeeding for 48 or 72 hours restored these parameters to normal in skeletal muscle of previously fasting rats. These observations suggest that a decrease in muscle Na+/K(+)-ATPase activity may lead to a compensatory increase in its alpha II subunit gene expression. The levels of insulin and not of glycemia appear to be critical in modulating Na+/K(+)-ATPase activity and gene expression.


Assuntos
Diabetes Mellitus Experimental/enzimologia , Músculos/enzimologia , RNA Mensageiro/análise , ATPase Trocadora de Sódio-Potássio/análise , Animais , Jejum , Alimentos , Masculino , Ratos , Ratos Endogâmicos , Sódio/metabolismo , ATPase Trocadora de Sódio-Potássio/genética
18.
Neoplasma ; 39(2): 73-7, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1356238

RESUMO

A vincristine resistant cell line was obtained from mouse leukemia cells L1210 by long-term adaptation in a medium with stepwise increasing concentrations of vincristine. By Western blotting using monoclonal antibody C219, positive signal on the presence of P-glycoprotein was observed in the resistant cells. Moreover, hybridization of mRNA from vincristine resistant cells with radiolabeled MDR1 cDNA probe gave evidence about the expression of MDR1 gene. The observed resistance may be depressed by application of "chemosensitizers" such as (1) calcium entry blockers (verapamil and nifedipine); (2) neuroleptics (trifluorperasine) and (3) local anesthetics (lidocaine) directly to the grow medium. Any significant effect in O2 consumption as well as incorporation of [U-14C]-glucose by the sensitive or resistant cells was not detected in the absence of vincristine. Presence of vincristine induced increasing velocity of O2 consumption by resistant cells from 2.5 +/- 0.3 to 3.3 +/- 0.2 microliters/min.10(6) cells, and, on the other hand, decreasing O2 consumption by sensitive cells from 2.3 +/- 0.2 to 1.7 +/- 0.1 ml/min.10(6) cells. The presence of vincristine induced less potent decrease in glucose incorporation by resistant cells in comparison with values which were observed in sensitive cells.


Assuntos
Adaptação Biológica/fisiologia , Leucemia L1210/tratamento farmacológico , Glicoproteínas de Membrana/fisiologia , Vincristina/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP , Animais , Sobrevivência Celular/efeitos dos fármacos , Meios de Cultura , Resistência a Medicamentos , Metabolismo Energético/efeitos dos fármacos , Glucose/metabolismo , Líquido Intracelular/metabolismo , Cinética , Leucemia L1210/metabolismo , Leucemia L1210/fisiopatologia , Camundongos , Consumo de Oxigênio/efeitos dos fármacos , Sensibilidade e Especificidade , Células Tumorais Cultivadas/efeitos dos fármacos , Vincristina/toxicidade
19.
J Natl Cancer Inst ; 83(10): 708-12, 1991 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-2023272

RESUMO

To prospectively assess the role of MDR1 gene expression in patients with de novo acute myeloid leukemia (AML), levels of MDR1 RNA in blast cells were determined at diagnosis and correlated with treatment outcome in 63 patients. MDR1 RNA levels were negative in 29% and positive in 71% of the patients. The complete remission rate in response to induction chemotherapy was 89% for MDR1 RNA-negative patients and 53% for MDR1 RNA-positive patients (P = .008). Expression of the MDR1 gene was observed in most patients who died early or had resistant disease. Kaplan-Meier curves revealed a decrease in both disease-free survival and overall survival of patients with detectable MDR1 gene expression compared with the disease-free survival and overall survival of MDR1 RNA-negative patients (P = .029 and P = .009, respectively). These data indicate that MDR1 gene expression is an unfavorable prognostic factor and suggest that multidrug resistance is important in AML.


Assuntos
Resistência a Medicamentos/genética , Expressão Gênica , Leucemia Mieloide Aguda/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Leucemia Eritroblástica Aguda/genética , Leucemia Eritroblástica Aguda/metabolismo , Leucemia Eritroblástica Aguda/mortalidade , Leucemia Monocítica Aguda/genética , Leucemia Monocítica Aguda/metabolismo , Leucemia Monocítica Aguda/mortalidade , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/mortalidade , Leucemia Mielomonocítica Aguda/genética , Leucemia Mielomonocítica Aguda/metabolismo , Leucemia Mielomonocítica Aguda/mortalidade , Leucemia Promielocítica Aguda/genética , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Análise de Sobrevida
20.
Eur J Cancer ; 27(11): 1352-5, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1835847

RESUMO

To prospectively assess the role of the MDR1 gene in breast carcinomas, MDR1 RNA levels of breast carcinoma specimens were determined by slot blot analysis. In 59 evaluable patients with primary breast carcinomas, MDR1 RNA levels of the carcinomas were negative in 54%, low in 29% and high in 17% of the patients. No differences in age, menopause status, oestrogen and progesterone receptor levels, tumour size, lymph node involvement and c-erbB-2/neu gene expression were observed between MDR1 RNA negative patients and MDR1 RNA positive patients.


Assuntos
Neoplasias da Mama/genética , Regulação Neoplásica da Expressão Gênica , Adulto , Idoso , Idoso de 80 Anos ou mais , Resistência a Medicamentos/genética , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , RNA Neoplásico/análise
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