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1.
Ann Oncol ; 25(11): 2277-2284, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25210016

RESUMO

BACKGROUND: This report provides a survival update at a follow-up of >5 years (5.5-6 years) for patients with advanced melanoma who previously received ipilimumab in phase II clinical trials. Safety and efficacy data following ipilimumab retreatment are also reported. PATIENTS AND METHODS: Patients who previously received ipilimumab 0.3, 3, or 10 mg/kg in one of six phase II trials (CA184-004, CA184-007, CA184-008, CA184-022, MDX010-08, and MDX010-15) were eligible to enroll in the companion study, CA184-025. Upon enrollment, patients initially received ipilimumab retreatment, extended maintenance therapy, or were followed for survival only. Overall survival (OS) rates were evaluated in patients from studies CA184-004, CA184-007, CA184-008, and CA184-022. Safety and best overall response during ipilimumab retreatment at 10 mg/kg were assessed in study CA184-025. RESULTS: Five-year OS rates for previously treated patients who received ipilimumab induction at 0.3, 3, or 10 mg/kg were 12.3%, 12.3%-16.5%, and 15.5%-28.4%, respectively. Five-year OS rates for treatment-naive patients who received ipilimumab induction at 3 or 10 mg/kg were 26.8% and 21.4%-49.5%, respectively. Little to no change in OS was observed from year 5 up to year 6. The objective response rate among retreated patients was 23%. Grade 3/4 immune-related adverse events occurred in 25%, 5.9%, and 13.2% of retreated patients who initially received ipilimumab 0.3, 3, and 10 mg/kg, with the most common being observed in the skin (4.2%, 2.9%, 3.8%) and gastrointestinal tract (12.5%, 2.9%, 3.8%), respectively. CONCLUSIONS: At a follow-up of 5-6 years, ipilimumab continues to demonstrate durable, long-term survival in a proportion of patients with advanced melanoma. In some patients, ipilimumab retreatment can re-establish disease control with a safety profile that is comparable with that observed during ipilimumab induction. Further studies are needed to determine the contribution of ipilimumab retreatment to OS. CLINICALTRIALSGOV: NCT00162123.


Assuntos
Anticorpos Monoclonais/administração & dosagem , Imunoterapia , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/imunologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/classificação , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Seguimentos , Humanos , Ipilimumab , Estimativa de Kaplan-Meier , Masculino , Melanoma/imunologia , Melanoma/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia
2.
Ann Oncol ; 21(8): 1712-1717, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20147741

RESUMO

BACKGROUND: This phase II study evaluated the safety and activity of ipilimumab, a fully human mAb that blocks cytotoxic T-lymphocyte antigen-4, in patients with advanced melanoma. PATIENTS AND METHODS: Patients with previously treated, unresectable stage III/stage IV melanoma received 10 mg/kg ipilimumab every 3 weeks for four cycles (induction) followed by maintenance therapy every 3 months. The primary end point was best overall response rate (BORR) using modified World Health Organization (WHO) criteria. We also carried out an exploratory analysis of proposed immune-related response criteria (irRC). RESULTS: BORR was 5.8% with a disease control rate (DCR) of 27% (N = 155). One- and 2-year survival rates (95% confidence interval) were 47.2% (39.5% to 55.1%) and 32.8% (25.4% to 40.5%), respectively, with a median overall survival of 10.2 months (7.6-16.3). Of 43 patients with disease progression by modified WHO criteria, 12 had disease control by irRC (8% of all treated patients), resulting in a total DCR of 35%. Adverse events (AEs) were largely immune related, occurring mainly in the skin and gastrointestinal tract, with 19% grade 3 and 3.2% grade 4. Immune-related AEs were manageable and generally reversible with corticosteroids. CONCLUSION: Ipilimumab demonstrated clinical activity with encouraging long-term survival in a previously treated advanced melanoma population.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Melanoma/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/efeitos adversos , Feminino , Humanos , Ipilimumab , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Metástase Neoplásica
3.
J Appl Crystallogr ; 50(Pt 3): 959-966, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28656043

RESUMO

A software package for the calibration and processing of powder X-ray diffraction and small-angle X-ray scattering data is presented. It provides a multitude of data processing and visualization tools as well as a command-line scripting interface for on-the-fly processing and the incorporation of complex data treatment tasks. Customizable processing chains permit the execution of many data processing steps to convert a single image or a batch of raw two-dimensional data into meaningful data and one-dimensional diffractograms. The processed data files contain the full data provenance of each process applied to the data. The calibration routines can run automatically even for high energies and also for large detector tilt angles. Some of the functionalities are highlighted by specific use cases.

4.
J Clin Oncol ; 17(9): 2752-61, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10561350

RESUMO

PURPOSE: Concurrent biochemotherapy results in high response rates but also significant toxicity in patients with metastatic melanoma. We attempted to improve its efficacy and decrease its toxicity by using decrescendo dosing of interleukin-2 (IL-2), posttreatment granulocyte colony-stimulating factor (G-CSF), and low-dose tamoxifen. PATIENTS AND METHODS: Forty-five patients with poor prognosis metastatic melanoma were treated at a community hospital inpatient oncology unit affiliated with the John Wayne Cancer Institute (Santa Monica, CA) between July 1995 and September 1997. A 5-day modified concurrent biochemotherapy regimen of dacarbazine, vinblastine, cisplatin, decrescendo IL-2, interferon alfa-2b, and tamoxifen was repeated at 21-day intervals. G-CSF was administered beginning on day 6 for 7 to 10 days. RESULTS: The overall response rate was 57% (95% confidence interval, 42% to 72%), the complete response rate was 23%, and the partial response rate was 34%. Complete remissions were achieved in an additional 11% of patients by surgical resection of residual disease after biochemotherapy. The median time to progression was 6.3 months and the median duration of survival was 11.4 months. At a maximum follow-up of 36 months (range, 10 to 36 months), 32% of patients are alive and 14% remain free of disease. Decrescendo IL-2 dosing and administration of G-CSF seemed to reduce toxicity, length of hospital stay, and readmission rates. No patient required intensive care unit monitoring, and there were no treatment-related deaths. CONCLUSION: The data from this study indicate that the modified concurrent biochemotherapy regimen reduces the toxicity of concurrent biochemotherapy with no apparent decrease in response rate in patients with poor prognosis metastatic melanoma.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Interleucina-2/administração & dosagem , Melanoma/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Idoso , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Dacarbazina/administração & dosagem , Dacarbazina/efeitos adversos , Intervalo Livre de Doença , Quimioterapia Combinada , Feminino , Fator Estimulador de Colônias de Granulócitos/efeitos adversos , Humanos , Interleucina-2/efeitos adversos , Masculino , Melanoma/patologia , Pessoa de Meia-Idade , Projetos Piloto , Dermatopatias/induzido quimicamente , Neoplasias Cutâneas/patologia , Tamoxifeno/administração & dosagem , Tamoxifeno/efeitos adversos , Vimblastina/administração & dosagem , Vimblastina/efeitos adversos
5.
J Invest Dermatol ; 117(2): 375-8, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11511319

RESUMO

Melanoma frequently metastasizes to the central nervous system (CNS). The diagnosis of CNS metastases typically is made following the onset of clinical symptoms. Thus, more sensitive diagnostic approaches are needed to identify subclinical CNS metastases. Currently, standard cytologic analysis of the cerebrospinal fluid (CSF) is limited by its poor sensitivity. A more sensitive assay was therefore developed using multiple reverse transcriptase-polymerase chain reaction (RT-PCR) markers. CSF was collected and assessed by RT-PCR for three known melanoma-associated markers (MAGE-3, MART-1, and tyrosinase) to detect occult metastatic melanoma cells in the CSF of 37 American Joint Committee on Cancer (AJCC) stage IV melanoma patients. Cytologic analysis of CSF was performed on all patients, and immunohistochemistry (IHC) analysis was performed on 33 CSF samples using anti-S100 and anti-HMB-45 antibodies. Only one patient (3%) had tumor-positive CSF cytology and IHC upon entry into the study, whereas 12 patients (32%) were positive for at least one RT-PCR marker. The correlation between CSF RT-PCR positivity of MART-1 and/or MAGE-3 and the development of CNS metastases at 3 mo was significant (p = 0.04). Fifteen of 37 patients (41%) had either positive MRI and/or positive RT-PCR results. Multimarker RT-PCR is more informative and sensitive than cytology/IHC in assessing the CSF of melanoma patients.


Assuntos
Antígenos de Neoplasias , Melanoma/líquido cefalorraquidiano , Melanoma/secundário , Neoplasias Cutâneas/líquido cefalorraquidiano , Neoplasias Cutâneas/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , DNA de Neoplasias/análise , DNA de Neoplasias/líquido cefalorraquidiano , Intervalo Livre de Doença , Feminino , Humanos , Antígeno MART-1 , Masculino , Melanoma/mortalidade , Pessoa de Meia-Idade , Monofenol Mono-Oxigenase/genética , Proteínas de Neoplasias/genética , Valor Preditivo dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/mortalidade
6.
J Clin Pathol ; 42(10): 1096-100, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2573621

RESUMO

The feasibility of comparative quality assessment studies in immunocytochemistry was examined. The reactions of three CD15 antibodies--anti-Leu M1, DM1, and Tü9--were examined in paraffin wax sections in Hodgkin's disease under a variety of different fixation and pre-treatment conditions, using four immunochemical detection techniques. All three antibodies stained Reed-Sternberg cells, but DM1 could be used at slightly higher dilutions to achieve comparable results. Tissue fixed in formol sublimate showed the most intense staining reactions, and formol saline and neutral buffered formalin gave relatively poor results. Although neuraminidase pre-treatment improved staining, its routine use is probably contraindicated by its high cost. Trypsinisation has some value for sections of tissue fixed in formol saline and neutral buffered formalin. The avidin-biotin complex technique produced the best results, but indirect immunoperoxidase produced acceptable results, is technically easier to perform, and is less expensive. It is concluded that information regarding variations in techniques and commercially available reagents, which may be of use in routine diagnostic histopathology, can be obtained by comparative quality assessment studies of this type.


Assuntos
Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Biomarcadores Tumorais/análise , Doença de Hodgkin/diagnóstico , Adulto , Antígenos de Diferenciação , Feminino , Humanos , Imuno-Histoquímica/economia , Antígenos CD15 , Masculino , Pessoa de Meia-Idade , Controle de Qualidade
7.
Environ Mol Mutagen ; 32(4): 351-9, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9882010

RESUMO

The potential of 1,3-dichloropropene (1,3-DCP) to induce dominant lethal mutations in the germ cells of male CD rats following inhalation exposure was investigated. Groups of 11-week-old males (30 animals/group) were exposed to 1,3-DCP vapors by inhalation at targeted concentrations of 0 (negative control), 10, 60, and 150 ppm for 10 weeks (6 hr/day, 7 days/week). An additional group of 30 males (designated the pairfed group) was kept on dietary restriction for 10 weeks. This group served as a control for any effects of decreased feed consumption and the associated body weight loss on the dominant lethal indices in the males exposed to 1,3-DCP. At the termination of the exposures, each male was cohoused with naive adult virgin CD females for two consecutive mating trials (1 week/trial, 2 females/male). Females were necropsied 13 days after the conclusion of each weekly mating trial and the number of corpora lutea, live implantations, and resorptions were determined. There were no statistically significant increases in either the pre- or postimplantation embryonic/fetal loss in females mated with 1,3-DCP-exposed males relative to controls at any weekly mating period. Based on these results, it can be concluded that 1,3-DCP is not mutagenic to the male germ cells of CD rats at exposure levels < or = 150 ppm, the highest concentration tested.


Assuntos
Compostos Alílicos/toxicidade , Genes Letais , Inseticidas/toxicidade , Mutagênicos/toxicidade , Compostos Alílicos/administração & dosagem , Animais , Implantação do Embrião , Feminino , Fertilidade/efeitos dos fármacos , Hidrocarbonetos Clorados , Exposição por Inalação , Inseticidas/administração & dosagem , Masculino , Mutagênicos/administração & dosagem , Mutação , Taxa de Gravidez , Ratos , Ratos Sprague-Dawley , Espermatogênese/efeitos dos fármacos
8.
Recent Results Cancer Res ; 158: 78-92, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11092035

RESUMO

Cutaneous melanoma is characterized by a high propensity for metastasis. Currently, surgical intervention remains the mainstay of therapy. This approach has proven most beneficial when the diagnosis is of early stage primary lesions. Likewise, patients undergoing resection for a solitary site of metastasis have shown a survival advantage. Identification of metastatic disease depends predominantly on radiographic techniques requiring the presence of significant tumor burdens for successful imaging. However, at that time, the role of surgery and/or biochemotherapy may be of limited value. Techniques to identify minimal disease states may permit more accurate assessment of prognosis. The detection of occult tumor cells by RT-PCR in the blood, lymph nodes, and bone marrow of melanoma patients provides one such approach to monitor tumor progression. Single-marker RT-PCR has been used as one such approach but is noted to have limitations in sensitivity and specificity based on the heterogeneity of tumor marker expression among tumors as well as within an individual tumor lesion or among multiple lesions in individual patients. We employed a multimarker reverse transcriptase polymerase chain reaction assay that demonstrates improved sensitivity over a single-marker approach. Currently, the consequences of detecting systemic subclinical metastasis remain unknown pending longer-term follow-up. The detection of occult melanoma cells using molecular techniques in conjunction with known clinicopathologic prognostic factors may provided a novel and efficient approach in monitoring tumor progression and further identify high-risk patients diagnosed early in the disease course.


Assuntos
Biomarcadores Tumorais/análise , Melanoma/diagnóstico , Células Neoplásicas Circulantes/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/diagnóstico , Medula Óssea/patologia , Humanos , Linfonodos/patologia , Melanoma/genética , Estadiamento de Neoplasias , Células Neoplásicas Circulantes/metabolismo , RNA Mensageiro/análise , Sensibilidade e Especificidade , Neoplasias Cutâneas/genética
9.
Neurosurgery ; 44(1): 59-64; discussion 64-6, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9894964

RESUMO

OBJECTIVE: Although the mainstays for treatment of metastatic brain disease have been surgery and/or external beam radiation therapy, an increasing number of patients are being referred for stereotactic radiosurgery as the primary intervention for their intracranial pathological abnormalities. The lack of efficacy and cognitive and behavioral consequences of whole brain irradiation have prompted clinicians to select patients for alternative therapies. This study analyzes the effectiveness of Leksell gamma unit therapy for metastatic melanoma to the brain. METHODS: We present our experience with 59 Leksell gamma unit treatment sessions in 45 consecutive patients who presented with metastatic melanoma to the brain. Five of these procedures were performed as salvage therapy for patients who needed second radiosurgical treatment for new lesions that were remote from the previous targets and were not included in the overall analyses. RESULTS: The population included 78% male patients. The mean patient age was 53 years (age range, 24-80 yr). The mean time from diagnosis of primary melanoma to discovery of brain metastasis was 43 months (median, 27.5 mo; range, 1-180 mo). At the time of diagnosis of brain disease, 35.5% of the patients (16 of 45 patients) had neurological symptoms, 77.7% (35 of 45 patients) had known visceral metastases, and 11.1% (5 of 45 patients) had seizure disorders. Eighty-six percent of the lesions (80 of 93 lesions) were cortical, 12% (11 of 93 lesions) were cerebellar, 1% (1 of 93 lesions) were pontine, and 1% (1 of 93 lesions) were thalamic. Fifty-seven percent of the sessions (31 of 54 sessions) were performed for a single lesion, 24.1% (13 of 54 sessions) for two lesions, 9.2% (5 of 54 sessions) for three lesions, 7.4% (4 of 54 sessions) for four lesions, and 1.8% (1 of 54 sessions) for five lesions. The mean treatment volume was 5.6 cc, with a mean prescription of 21.6 Gy to the 56.0% mean isodose line. The median survival time of the patients in our population, using Kaplan-Meier curves, was 43 months from the time of diagnosis of primary melanoma (range, 3-180 mo) and 8 months (range, 1-20 mo) from the time of gamma knife treatment. Complications included seizures within 24 hours of the procedure in four patients, with transient nausea and vomiting in three patients, transient worsening of preprocedure paresis responsive to steroids in three patients, and increased confusion in one patient. All 45 patients were located for follow-up (mean follow-up duration, 1 yr). After gamma knife treatment, 78% of the patients (35 of 45 patients) experienced either improved or stable neurological symptomatology before death or at the time of the latest follow-up examination. There were 26 deaths (58%). The cause of death was determined to be neurological in only 2 of 45 patients (7.7%). Follow-up magnetic resonance images revealed a 97% local tumor control rate of gamma knife-treated lesions, with 28% radiographic disappearance (9 of 32 cases). Six patients developed new lesions remote from radiosurgical targets and underwent second procedures. CONCLUSION: Although metastatic melanoma to the brain continues to have a foreboding prognosis for long-term survival, gamma knife radiosurgery seems to be a relatively safe, noninvasive, palliative therapy, halting or reversing neurological progression in 77.8% of treated patients (35 of 45 patients). The survival rate matches or exceeds those previously reported for surgery and other forms of radiotherapy. Only 7.7% of the patients in our study population who died as a result of metastatic melanoma (2 of 26 patients) died as a result of neurological disease. The routine use of therapeutic level antiseizure medication is emphasized, considering the findings of our review.


Assuntos
Neoplasias Encefálicas/secundário , Melanoma/secundário , Complicações Pós-Operatórias/etiologia , Radiocirurgia , Neoplasias Cutâneas/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/cirurgia , Causas de Morte , Feminino , Seguimentos , Humanos , Masculino , Melanoma/mortalidade , Melanoma/cirurgia , Pessoa de Meia-Idade , Exame Neurológico , Complicações Pós-Operatórias/mortalidade , Neoplasias Cutâneas/mortalidade , Taxa de Sobrevida , Resultado do Tratamento
10.
Mutat Res ; 444(1): 217-25, 1999 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-10477357

RESUMO

2,4-dichlorophenoxyacetic acid and its derivatives (collectively known as 2,4-D) are herbicides used to control a wide variety of broadleaf and woody plants. The genetic toxicity of an ester (2,4-D 2-butoxyethylester) and two salts (2,4-D isopropylamine and 2,4-D triisopropanolamine) was investigated in cultured mammalian cells. The end points used were the induction of chromosomal aberrations in primary cultures of rat lymphocytes and forward mutations at the HGPRT locus of Chinese hamster ovary cells. There was no evidence of genotoxicity for the test materials in the experimental systems used. These results were consistent with the general lack of genotoxic potential for 2,4-D in a number of other test systems.


Assuntos
Ácido 2,4-Diclorofenoxiacético/toxicidade , Herbicidas/toxicidade , Mutagênicos/toxicidade , Ácido 2,4-Diclorofenoxiacético/análogos & derivados , Animais , Células CHO , Aberrações Cromossômicas , Cricetinae , Hipoxantina Fosforribosiltransferase/genética , Linfócitos/efeitos dos fármacos , Testes de Mutagenicidade , Ratos
11.
Community Dent Oral Epidemiol ; 17(5): 248-51, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2791515

RESUMO

The life-span of amalgam restorations placed in primary molars by three general dental practitioners is investigated. Two methods of analysis have been carried out. In the analysis of "non-independent" restorations (i.e. using several restorations from each mouth), the median survival time was 52.8 months with an apparent standard error of 2.1 months. In the analysis of "independent" restorations (i.e. only using one restoration from each mouth), three random samples were chosen and their median survival times were 68.2 months (s.e. = 6.9), 60.5 months (s.e. = 6.9), and 56.8 months (s.e. = 3.7). The two methods are compared and discussed. It is concluded that the analysis of "independent" restorations should be the method of choice in studying the life-span of restorations.


Assuntos
Análise Atuarial/métodos , Amálgama Dentário , Restauração Dentária Permanente , Criança , Inglaterra , Odontologia Geral , Humanos , Dente Molar , Viés de Seleção , Dente Decíduo
12.
BMJ ; 299(6700): 663-5, 1989 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-2508857

RESUMO

Methods for determining sample size and power when comparing two groups in clinical trials are widely available. Studies comparing three or more treatments are not uncommon but are more difficult to analyse. A linear nomogram was devised to help calculate the sample size required when comparing up to five parallel groups. It may also be used retrospectively to determine the power of a study of given sample size. In two worked examples the nomogram was efficient. Although the nomogram offers only 5% and 1% significance levels and can be used only for up to five treatment groups, this is sufficient for most researchers.


Assuntos
Ensaios Clínicos como Assunto/métodos , Interpretação Estatística de Dados , Estudos de Amostragem , Análise de Variância , Ensaios Clínicos como Assunto/estatística & dados numéricos , Tratamento Farmacológico , Humanos
13.
J Dent ; 16(3): 150, 1988 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-3165996
16.
Philos Trans A Math Phys Eng Sci ; 368(1919): 2579-83, 2010 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-20403843
17.
Stat Med ; 7(11): 1187-94, 1988 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2974173

RESUMO

This paper considers the problem of comparing proportions in clinical trials where two parallel groups are studied. The question of what will happen to the response rate of an active therapy if some external factor affects the placebo rate is asked and two different, but similar, answers are proposed. Assuming either a logistic or probit model has substantial influence on the sample size required to detect differences and optimal comparisons are suggested. The idea is illustrated by a clinical trial of treatment for peptic ulcer and suggestions for other possible applications are presented.


Assuntos
Ensaios Clínicos como Assunto/métodos , Placebos/uso terapêutico , Acne Vulgar/terapia , Eletrocoagulação , Feminino , Humanos , Masculino , Úlcera Péptica Hemorrágica/cirurgia , Prognóstico , Distribuição Aleatória , Projetos de Pesquisa , Estudos de Amostragem , Estatística como Assunto
18.
Stat Med ; 10(1): 33-43, 1991 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2006354

RESUMO

Methods for estimating required sample size for comparing two population means have been published. Most involve the use of complicated formulae and tables. These methods are limited to comparing two groups. Although techniques exist to determine sample sizes for comparing more than two groups, they are intrinsically far more complicated. A simple linear nomogram is proposed as a solution to these problems, and its use is illustrated with examples of parallel group, ordered parallel group and factorial designs.


Assuntos
Ensaios Clínicos como Assunto/métodos , Viés de Seleção , Algoritmos , Análise de Variância , Pressão Sanguínea/efeitos dos fármacos , Humanos
19.
J Pathol ; 148(3): 217-24, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3009766

RESUMO

The expression of transferrin receptor by normal, pregnant and benign hyperplastic breast lesions and by breast carcinomas has been investigated immunohistochemically using two monoclonal antibodies directed against the receptor. Unlike a previous immunohistological study in which staining was confined to malignant breast, transferrin receptor has been detected in pregnant breast and in benign lesions as well as in all carcinomas examined. The latter showed variable reactivity but with staining of most cells in 70 per cent of cases. Although the expression of transferrin receptor in non-malignant conditions may be related to cell proliferation, as has been suggested from studies of activated cells, the extent of reactivity of carcinomas has shown no correlation with tumour characteristics such as differentiation and local tumour spread. It is therefore suggested that the immunologically active transferrin receptor of breast carcinomas may have significance other than that relating to proliferation. The finding that with some carcinomas differences in staining occurred between the two antibodies is a further illustration of the complexities of the nature of transferrin receptor.


Assuntos
Neoplasias da Mama/metabolismo , Receptores de Superfície Celular/metabolismo , Adenofibroma/metabolismo , Anticorpos Monoclonais , Mama/metabolismo , Doenças Mamárias/metabolismo , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Mitose , Gravidez , Receptores da Transferrina , Transferrina/metabolismo
20.
Artigo em Inglês | MEDLINE | ID: mdl-3088828

RESUMO

The incidence and significance of the expression of the antigen defined by the monoclonal antibody Ca 19.9 (Sialyl Lea) has been assessed in human breast tissue. Frozen and formalin-fixed, paraffin embedded specimens of normal, hyperplastic, pregnant breast and carcinomas were examined using an immunoperoxidase technique. Ductal and acinar epithelium of normal and hyperplastic tissues showed variable reactivity in frozen sections but there was a reduction in staining in comparable samples after fixation and processing, such that in many instances only focal ductal epithelium reacted. A distinctive feature in the pregnant breast was the absence of staining in acini showing differentiated secretory activity, despite a reaction in adjacent nonsecretory acini and ducts. The overall incidence of detection of the Ca 19.9 antigen in breast carcinomas was 62%, but in half of these only a small number of cells stained. A significant relationship between expression of Sialyl Lea and poor differentiation of carcinomas was identified, but there was no correlation with local lymph node status. In contrast to the non-malignant tissue fixation and processing had little effect on the reactivity of carcinomas. It is suggested that this difference may be quantitative in nature, with malignant breast showing much greater expression, or be related to organisation of the antigen. The observations concerning carcinomas and pregnant breast indicate that the synthesis of the Ca 19.9 antigen is related to the state of differentiation and functional activity of human breast.


Assuntos
Anticorpos Monoclonais , Antígenos de Neoplasias/análise , Neoplasias da Mama/análise , Antígenos Glicosídicos Associados a Tumores , Mama/análise , Feminino , Doença da Mama Fibrocística/patologia , Histocitoquímica , Humanos , Linfonodos/patologia , Neuraminidase/metabolismo , Gravidez , Primeiro Trimestre da Gravidez , Segundo Trimestre da Gravidez
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