Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 167
Filtrar
1.
Ann Oncol ; 28(8): 1811-1816, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28472240

RESUMO

BACKGROUND: Chemotherapy-induced premature ovarian insufficiency (POI) impacts fertility and other aspects of women's health. The OPTION trial tested whether administration of a gonadotropin-releasing hormone agonist during chemotherapy for early breast cancer reduced the risk of POI. PATIENTS AND METHODS: This was a prospective, randomized, parallel group study of the gonadotropin-releasing hormone agonist goserelin administered before and during chemotherapy for breast cancer with stage I-IIIB disease. The primary outcome was amenorrhoea between 12 and 24 months after randomization, supported by elevated follicle stimulating hormone concentrations to give an additional analysis as rate of POI. RESULTS: A total of 227 patients were randomized and the primary analysis was conducted on 202 patients. Goserelin reduced the prevalence of amenorrhoea between 12 and 24 months to 22% versus 38% in the control group (P = 0.015) and the prevalence of POI to 18.5% versus 34.8% in the control group (P = 0.048). Follicle stimulating hormone concentrations were also lower in all women treated with goserelin at both 12 and 24 months (P = 0.027, P = 0.001, respectively). The effect of goserelin was not statistically significant in women >40 years. Assessment of the ovarian reserve using anti-Müllerian hormone showed a marked fall in both groups during treatment to median values of 5% of pretreatment levels in the control group and 7% in the goserelin group, which were not significantly different between groups. CONCLUSION: This study shows that goserelin reduced the risk of POI in women treated with chemotherapy for early breast cancer, with particular efficacy in women aged ≤40 years old. The degree of ovarian protection also seems limited and the clinical significance for fertility and longer term prevention of estrogen deficiency-related outcomes needs to be determined.


Assuntos
Amenorreia/prevenção & controle , Antineoplásicos Hormonais/uso terapêutico , Antineoplásicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Hormônio Liberador de Gonadotropina/agonistas , Gosserrelina/uso terapêutico , Insuficiência Ovariana Primária/prevenção & controle , Adulto , Amenorreia/induzido quimicamente , Antineoplásicos/uso terapêutico , Antineoplásicos Hormonais/administração & dosagem , Diagnóstico Precoce , Feminino , Gosserrelina/administração & dosagem , Humanos , Insuficiência Ovariana Primária/induzido quimicamente , Estudos Prospectivos
2.
Disasters ; 37(2): 267-92, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23278356

RESUMO

The failure of food security and livelihood interventions to adapt to conflict settings remains a key challenge in humanitarian responses to protracted crises. This paper proposes a social capital analysis to address this policy gap, adding a political economy dimension on food security and conflict to the actor-based livelihood framework. A case study of three hillsides in north Burundi provides an ethnographic basis for this hypothesis. While relying on a theoretical framework in which different combinations of social capital (bonding, bridging, and linking) account for a diverse range of outcomes, the findings offer empirical insights into how social capital portfolios adapt to a protracted crisis. It is argued that these social capital adaptations have the effect of changing livelihood policies, institutions, and processes (PIPs), and clarify the impact of the distribution of power and powerlessness on food security issues. In addition, they represent a solid way of integrating political economy concerns into the livelihood framework.


Assuntos
Emergências , Abastecimento de Alimentos , Socorro em Desastres/organização & administração , Apoio Social , Altruísmo , Burundi , Humanos , Política , Poder Psicológico
3.
J Radiol Prot ; 32(1): N77-80, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22394998

RESUMO

The only unequivocal radiological effect of the Chernobyl accident on human health is the increase in thyroid cancer in those exposed in childhood or early adolescence. Cancer is a complicated disease and it is unclear whether the mechanism by which radiation gives rise to cancer differs from that involved in the generation of cancers of the same type by other environmental stimuli. The Chernobyl Tissue Bank was established in response to the scientific interest in studying the molecular biology of thyroid cancer after Chernobyl to address this question. The project is supported by the governments of Ukraine and Russia, and financially supported (in total around US$3 million) by the European Commission, the National Cancer Institute of the USA and the Sasakawa Memorial Health Foundation of Japan. The project began collecting a variety of biological samples from patients on 1 October 1988, and has supplied material to 23 research projects in Japan, the USA and Europe. The establishment of the Chernobyl Tissue Bank has facilitated co-operation between these research projects and the combination of clinical and research data provides a paradigm for cancer research in the molecular biological age.


Assuntos
Pesquisa Biomédica/organização & administração , Acidente Nuclear de Chernobyl , Neoplasias Induzidas por Radiação/patologia , Neoplasias da Glândula Tireoide/patologia , Bancos de Tecidos/organização & administração , Humanos , Ucrânia
4.
Gut ; 59(9): 1200-6, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20650924

RESUMO

INTRODUCTION: Benefits of immunosuppressive therapy in Crohn's disease have been demonstrated in controlled trials; however, it is unclear whether these drugs alter the longer-term natural history of this condition. AIMS AND METHODS: To assess changes in disease outcomes in a population-based cohort of patients diagnosed in Cardiff from 1986 to 2003. Case notes from Crohn's disease incidence studies in Cardiff were reviewed retrospectively for disease characteristics and follow-up information on drug therapy, and the need for surgery for Crohn's disease. The study population was divided into three groups by year of diagnosis (Group A=1986-1991, Group B=1992-1997 and Group C=1998-2003). RESULTS: 341 patients were included. Kaplan-Meier (KM) analysis showed increasing use of immunosuppressants over time. At 5 years after diagnosis this was 11% in Group A, 28% in Group B, and 45% in Group C (p=0.001) and the median time to start of thiopurines was 77, 21 and 11 months in Group A, B and C respectively. There was a significant reduction in long-term steroid use at 5 years post diagnosis: 45 (44%), 31 (31%) and 24 (19%) patients in Group A, B and C respectively (p=0.001). KM analysis showed a significant reduction in the cumulative probability of intestinal surgery: At 5 years this was 59% (Group A), 37% (Group B) and 25% (Group C) (p=0.001). In a multivariate Cox analysis, year of diagnosis, disease location, oral corticosteroids within 3 months of diagnosis and early thiopurine use (within the first year of diagnosis) were all independent factors affecting likelihood of intestinal surgery. CONCLUSION: This population-based cohort shows marked changes in rates of surgery, and the reduction is independently associated with year of diagnosis, and associated temporally with increased and earlier thiopurine use.


Assuntos
Doença de Crohn/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Azatioprina/uso terapêutico , Criança , Pré-Escolar , Doença de Crohn/epidemiologia , Doença de Crohn/cirurgia , Procedimentos Cirúrgicos do Sistema Digestório/estatística & dados numéricos , Procedimentos Cirúrgicos do Sistema Digestório/tendências , Esquema de Medicação , Métodos Epidemiológicos , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/efeitos adversos , Imunossupressores/uso terapêutico , Masculino , Mercaptopurina/uso terapêutico , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Neoplasias/etiologia , País de Gales/epidemiologia , Adulto Jovem
5.
Science ; 264(5165): 1570-2, 1994 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-17769600

RESUMO

The fullerene C(60) can be converted into two different structures by high pressure and temperature. They are metastable and revert to pristine C(60) on reheating to 300 degrees C at ambient pressure. For synthesis temperatures between 300 degrees and 400 degrees C and pressures of 5 gigapascals, a nominal face-centered-cubic structure is produced with a lattice parameter a(o) = 13.6 angstroms. When treated at 500 degrees to 800 degrees C at the same pressure, C(60) transforms into a rhombohedral structure with hexagonal lattice parameters of a(o) = 9.22 angstroms and c(o) = 24.6 angstroms. The intermolecular distance is small enough that a chemical bond can form, in accord with the reduced solubility of the pressure-induced phases. Infrared, Raman, and nuclear magnetic resonance studies show a drastic reduction of icosahedral symmetry, as might occur if the C(60) molecules are linked.

6.
Clin Oncol (R Coll Radiol) ; 21(2): 81-5, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19071000

RESUMO

Breast cancer incidence increases with age, but there are important age-related differences with respect to the frequency of different tumour subtypes with respect to hormone receptor status and pathological grade. In general, younger patients show a higher frequency of oestrogen receptor-negative, higher-grade tumours, whereas in older patients there is a higher frequency of oestrogen receptor-positive, low-grade tumours. This accounts for the fact that, in general, elderly patients are thought to have a less aggressive form of the disease. However, this does not mean that all elderly patients with breast cancer necessarily have a good prognosis. An increased understanding of the mechanisms of tissue ageing and how these affect the molecular biological phenotype of breast cancers in cohorts of different ages will aid the oncologist's confidence in tailoring treatment more appropriately to the likely prognosis, and the development of novel, hopefully less toxic, treatments for specific subtypes of breast cancer in the elderly population.


Assuntos
Envelhecimento/fisiologia , Neoplasias da Mama/patologia , Idoso , Neoplasias da Mama/classificação , Feminino , Humanos , Imunofenotipagem
7.
Cancer Res ; 51(2): 639-43, 1991 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-1670763

RESUMO

The loss of genetic material from specific chromosomal locations in a given tumor type has been taken for evidence of the importance of tumor suppressor genes at these loci in the genesis of the tumor. The primitive neuroectodermal tumor of the central nervous system has such a loss on 17p in one-third of tumors. In this report, a detailed analysis of 17p loss in 23 tumors has been performed using 10 probes mapping to this region. In addition, an analysis for allelic deletion on chromosomes 6q, 16q, and 22q has been performed. Six of the 23 tumors showed loss of markers on 17p, and the area of common loss spanned 17p11.2 to 17pter. Five of 23 tumors showed loss of markers on 6q, and 3 showed loss on 16q. No tumor lost markers on 22q. Only one tumor showed loss at more than one location. These data suggest that primitive neuroectodermal tumors either are a heterogeneous group of tumors with more than one mechanism leading to a tumor or that more than one recessive oncogene may play a role in the genesis of these tumors.


Assuntos
Neoplasias Encefálicas/genética , Cromossomos Humanos Par 16 , Cromossomos Humanos Par 17 , Cromossomos Humanos Par 6 , Meduloblastoma/genética , Adulto , Criança , Pré-Escolar , Deleção Cromossômica , Mapeamento Cromossômico , Sondas de DNA , Feminino , Genótipo , Heterozigoto , Humanos , Lactente , Masculino , Oncogenes , Polimorfismo de Fragmento de Restrição
8.
Cancer Res ; 49(23): 6572-7, 1989 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-2573417

RESUMO

Loss of constitutional heterozygosity for specific chromosomal loci, when found consistently in a particular tumor type, suggests that a recessive oncogene important in the genesis of that tumor may be present within the involved chromosomal loci. DNA markers that detect restriction fragment length polymorphisms are powerful tools that have been used to detect loss of chromosomal loci in a growing number of human malignancies. The human brain tumor astrocytoma is usually malignant and virtually incurable. Two types of malignant astrocytomas are recognized histopathologically:anaplastic astrocytoma and glioblastoma multiforme. We carried out a restriction fragment length polymorphism analysis of tumors from 15 patients with anaplastic astrocytoma and 20 patients with glioblastoma using polymorphic DNA markers for loci on chromosome 17. Loss of constitutional heterozygosity for loci on chromosome 17 was found in both anaplastic astrocytoma and glioblastoma patients with equal frequency (40% of cases). Our mapping data revealed a region of loss on chromosome 17p between physical loci p11.2 and pter that was common to both patient groups. Taken together with the previously reported finding of loss of heterozygosity for loci on chromosome 10 in glioblastoma, these results indicate that tumorigenesis in the astrocyte lineage may involve recessive oncogenes on two different chromosomes.


Assuntos
Astrocitoma/genética , Cromossomos Humanos Par 17 , Glioblastoma/genética , Heterozigoto , Mapeamento Cromossômico , DNA de Neoplasias/genética , Humanos , Oncogenes , Polimorfismo de Fragmento de Restrição
9.
Cancer Res ; 50(18): 5784-9, 1990 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-1975510

RESUMO

Astrocytoma, the most common brain tumor in humans, is usually malignant and virtually incurable. Two types of malignant astrocytomas can be distinguished histopathologically: anaplastic astrocytoma and glioblastoma multiforme. Studies using DNA markers that detect restriction fragment length polymorphisms have shown that loci on chromosomes 10 and 17p are lost frequently in tumor DNA from malignant astrocytoma patients, suggesting that tumor suppressor genes important in astrocytoma tumorigenesis may be present on 2 different chromosomes. To identify additional regions of chromosome loss, we carried out an allelotype analysis of 41 malignant astrocytoma patients using restriction fragment length polymorphism markers for each arm of every human autosome. Loss of heterozygosity was found for every autosome except chromosome 21, indicating an even greater complexity of genomic alterations than reported previously. Many tumors showed loss of heterozygosity for multiple chromosomes and the number of chromosomes involved correlated with tumor histopathology. A high-resolution restriction fragment length polymorphism study of chromosome 10 loci in these patients showed that loss of broad regions of chromosome 10 was a common event, particularly in glioblastoma multiforme. An allelotype analysis has been carried out on only one other tumor, human colorectal carcinoma. Different profiles of allele loss were observed in malignant astrocytoma and colorectal carcinoma, suggesting that the genetic events leading to these 2 human cancers may proceed along different pathways.


Assuntos
Alelos , Astrocitoma/genética , Neoplasias Encefálicas/genética , Cromossomos Humanos Par 10 , Neoplasias Colorretais/genética , Glioblastoma/genética , Heterozigoto , Humanos , Polimorfismo de Fragmento de Restrição , Supressão Genética
10.
Cancer Res ; 56(9): 2167-70, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8616867

RESUMO

Mutations in the RET proto-oncogene are associated with the pathogenesis of medullary thyroid carcinoma (MTC). In an attempt to understand this process, we examined microdissected subpopulations from MTC and multiple metastases from these tumors. Approximately 80% of sporadic MTC's had at least one subpopulation with the RET codon 918 mutation, which is a mutation previously detected in sporadic MTC as a somatic mutation and in multiple endocrine neoplasia type 2B as a germline mutation. However, the distribution of this mutation was nonhomogeneous, occurring only in subpopulations in most tumors and among subsets of multiple metastases, thus implying that although the codon 918 mutation could be an early event, it is not necessarily an early or essential event in tumorigenesis. This heterogeneity suggests either that the codon 918 mutation can arise as an event in progression within a metastatic clone or within a single tumor, or that MTC can be of polyclonal origin. Of significance, one of two multiple endocrine neoplasia type 2A MTCs carried a somatic mutation at codon 918, in addition to the RET mutation present in the germline. We found no correlation between the presence of other somatic genetic events, such as loss of heterozygosity on chromosome arms 1p and 22q, and RET mutation status in the various subpopulations of MTC.


Assuntos
Carcinoma Medular/genética , Proteínas de Drosophila , Proteínas Proto-Oncogênicas/genética , Receptores Proteína Tirosina Quinases/genética , Neoplasias da Glândula Tireoide/genética , Carcinoma Medular/patologia , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 22 , Humanos , Mutação , Metástase Neoplásica , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-ret , Neoplasias da Glândula Tireoide/patologia
11.
Clin Oncol (R Coll Radiol) ; 28(4): 231-6, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26880062

RESUMO

Our acceptance of exposure to radiation is somewhat schizophrenic. We accept that the use of high doses of radiation is still one of the most valuable weapons in our fight against cancer, and believe that bathing in radioactive spas is beneficial. On the other hand, as a species, we are fearful of exposure to man-made radiation as a result of accidents related to power generation, even though we understand that the doses are orders of magnitude lower than those we use everyday in medicine. The 70th anniversary of the detonation of the atomic bombs in Hiroshima and Nagasaki was marked in 2015. The 30th anniversary of the Chernobyl nuclear power plant accident will be marked in April 2016. March 2016 also sees the fifth anniversary of the accident at the Fukushima nuclear power plant. Perhaps now is an opportune time to assess whether we are right to be fearful of the effects of low doses of radiation, or whether actions taken because of our fear of radiation actually cause a greater detriment to health than the direct effect of radiation exposure.


Assuntos
Efeitos da Radiação , Exposição à Radiação , Fatores Etários , Radiação de Fundo , Acidente Nuclear de Chernobyl , Relação Dose-Resposta à Radiação , Acidente Nuclear de Fukushima , Humanos , Neoplasias Induzidas por Radiação/etiologia , Guerra Nuclear , Doses de Radiação , Exposição à Radiação/efeitos adversos , Liberação Nociva de Radioativos , Radioterapia , Medição de Risco
12.
Thyroid ; 15(2): 100-4, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15753666

RESUMO

In both medullary carcinoma and papillary carcinoma of the thyroid, altered expression of the RET gene is implicated in tumorigenesis. Recent studies suggest that loss of heterozygosity (LOH) at the G691S SNP may be associated with tumors from patients with a history of radiation exposure. We investigated LOH for three RET SNPs (G691S, S904S, and L769L) in tumor and normal tissue from 46 patients from Ukraine and Belarus who were exposed to radioactive fallout following the Chernobyl nuclear accident and were operated for papillary thyroid carcinoma between 1995 and 2000. Normal tissue from 28 patients was heterozygous for at least one SNP; DNA from the corresponding tumor samples was also heterozygous, indicating that no LOH had taken place. To assess SNP frequencies in a radiation-associated thyroid cancer cohort, we investigated a further 68 unpaired post-Chernobyl samples. For G691S, there was considerable deviation from Hardy-Weinberg equilibrium; more detailed analysis showed that this was linked to age at onset of disease. Among younger patients, the distribution of genotypes conformed to Hardy-Weinberg equilibrium; among older patients, we observed marked deviation (p = 0.0072), with significant over-representation of the rare S allele relative to the younger groups (Fisher's exact, p = 0.0233). This suggests that SNPs in the RET oncogene may play a role in sporadic papillary thyroid carcinoma.


Assuntos
Carcinoma Papilar/genética , Perda de Heterozigosidade , Neoplasias Induzidas por Radiação/genética , Proteínas Oncogênicas/genética , Polimorfismo de Nucleotídeo Único , Receptores Proteína Tirosina Quinases/genética , Neoplasias da Glândula Tireoide/genética , Adolescente , Adulto , Idoso , Acidente Nuclear de Chernobyl , Criança , Estudos de Coortes , Frequência do Gene , Ligação Genética , Humanos , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-ret , Cinza Radioativa/efeitos adversos , República de Belarus , Ucrânia
13.
Dig Liver Dis ; 37(11): 832-7, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16169302

RESUMO

BACKGROUND: Smoking increases plasma fibrinogen and cardiovascular risk whereas transdermal nicotine may not. Fibrinogen is an acute phase protein and may reflect disease activity in ulcerative colitis. AIMS: To examine the effect of topical nicotine on plasma fibrinogen and any relationship between fibrinogen and ulcerative colitis disease activity. PATIENTS: Forty-eight non-smokers with moderately active ulcerative colitis. METHODS: Patients were randomised to 6 mg nicotine enema or placebo for 6 weeks, followed by open nicotine therapy for 4 weeks. Plasma fibrinogen was measured at baseline and after 6 and 10 weeks; at each assessment sigmoidoscopy with a rectal biopsy was performed. RESULTS.: At 6 weeks median plasma fibrinogen was 3.30 g/l on nicotine compared to 3.05 g/l on placebo, P = 0.90 when adjusted for baseline values. There was a correlation between fibrinogen and the UC disease activity index (UCDAI) at weeks 0 and 10, P = 0.036 and 0.033, respectively, and between fibrinogen and sigmoidoscopic grade at each assessment, P = 0.014, 0.021 and 0.034. Changes in fibrinogen did not correlate with changes in disease severity. CONCLUSIONS: There was no significant effect of nicotine enemas, in either direction, on plasma fibrinogen-this was raised in moderately active UC and correlated with the sigmoidoscopic grade of colitis and the UCDAI; however, fibrinogen was not sufficiently sensitive to be of practical clinical value.


Assuntos
Colite Ulcerativa/sangue , Fibrinogênio/análise , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Enema , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Sensibilidade e Especificidade , Sigmoidoscopia
14.
Leukemia ; 13(1): 135-41, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10049049

RESUMO

Five pediatric patients are described with acute lymphoblastic leukemia (ALL) who at presentation had clinical findings suggestive of B cell ALL and lymphoblasts with FAB L3 morphology and the characteristic t(8;14)(q24;q32). However, the leukemia cells of all five patients failed to express surface immunoglobulin (sIg) and kappa or lambda light chains. Based on initial immunophenotyping results consistent with B-precursor ALL, four of these cases were initially treated with conventional ALL chemotherapy. These four patients were switched to B cell ALL treatment protocols once cytogenetic results became available revealing the 8;14 translocation. The fifth case was treated with B cell ALL therapy from the outset. Four of the five patients are in complete remission at 64, 36, 29 and 13 months from diagnosis. One patient relapsed and died 6 months after initial presentation. These five unusual cases with clinical B cell ALL, the t(8;14), and FAB L3 morphology, but negative sIg, demonstrate the importance of careful and multidisciplinary evaluation of leukemic cells with morphology, cytochemistry, immunophenotyping and cytogenetic analysis. Future identification of patients with this profile will allow us to expand our knowledge regarding prognostic significance and optimal treatment for this rare subgroup of patients.


Assuntos
Linfócitos B/imunologia , Linfoma de Burkitt/genética , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 8 , Translocação Genética , Adolescente , Antígenos CD/análise , Linfócitos B/patologia , Medula Óssea/patologia , Linfoma de Burkitt/sangue , Linfoma de Burkitt/imunologia , Linfoma de Burkitt/patologia , Criança , Pré-Escolar , Mapeamento Cromossômico , Feminino , Humanos , Masculino
15.
Postgrad Med J ; 81(959): 594-8, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16143691

RESUMO

BACKGROUND: Therapeutic enemas are often used to treat active colitis but their retention may be limited because of urgency to defecate. Some preparations may be better retained and tolerated than others because of their physical properties. AIM: To compare patient preference and retention of four therapeutic enemas, including a nicotine enema, in patients with ulcerative colitis (UC). METHODS: Twenty four patients with active UC received the four trial enemas-corticosteroid, 5-amino salicylate (5-ASA), and nicotine liquid enemas and a corticosteroid foam, in a randomised order, taking one enema on each of four successive nights. Patients scored them 1 to 4 for ease of administration and retention, degree of abdominal bloating, and for their overall preference. RESULTS: Fifteen patients rated nicotine their overall favourite or second favourite, compared with 14 for corticosteroid foam and 11 for 5-ASA and corticosteroid liquids, but this was not significant (p = 0.302). Overall, there was no significant difference in overnight retention. However, the nicotine enema tended to be less well retained in patients with milder urgency but a higher proportion retained it overnight with more severe urgency (p = 0.031 compared with 5-ASA enema). CONCLUSION: There was no significant difference in patient preference or overall duration of retention for the four enemas.


Assuntos
Colite Ulcerativa/terapia , Enema/métodos , Fármacos Gastrointestinais/uso terapêutico , Satisfação do Paciente , Corticosteroides/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Enema/psicologia , Enema/normas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/uso terapêutico
16.
Vision Res ; 111(Pt A): 13-21, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25872175

RESUMO

The eye is an important sense organ for teleost species but can vary greatly depending on the adaption to the habitat, environment during ontogeny and developmental stage of the fish. The eye and retinal morphology of eight commonly caught trawl bycatch species were described: Lepidotrigla mulhalli; Lophonectes gallus; Platycephalus bassensis; Sillago flindersi; Neoplatycephalus richardsoni; Thamnaconus degeni; Parequula melbournensis; and Trachurus declivis. The cone densities ranged from 38 cones per 0.01 mm(2) for S. flindersi to 235 cones per 0.01 mm(2) for P. melbournensis. The rod densities ranged from 22800 cells per 0.01 mm(2) for L. mulhalli to 76634 cells per 0.01 mm(2) for T. declivis and potential visual acuity (based on anatomical measures) ranged from 0.08 in L. gallus to 0.31 in P. melbournensis. Higher rod densities were correlated with maximum habitat depths. Six species had the regular pattern of four double cones arranged around a single cone in the photoreceptor mosaic, while T. declivis had only rows of double cones. P. melbournensis had the greatest potential ability for detecting fine detail based on eye anatomy. The potential visual acuity estimates and rod densities can be applied to suggest the relative detection ability of different species in a commercial fishing context, since vision is a critical sense in an illuminated environment for perceiving an oncoming trawl.


Assuntos
Peixes/fisiologia , Células Fotorreceptoras Retinianas Cones/citologia , Células Fotorreceptoras Retinianas Bastonetes/citologia , Acuidade Visual/fisiologia , Análise de Variância , Animais , Contagem de Células , Olho/anatomia & histologia , Cristalino/anatomia & histologia , Visão Ocular
17.
J Invest Dermatol ; 109(6): 770-7, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9406819

RESUMO

Previous studies have investigated the expression of insulin-like growth factor-I (IGF-I) and its receptor in cultured skin cells or in whole skin. In order to fully understand the role of IGF-I in the skin and its appendages, however, a comprehensive study that details the expression of IGF-I and the IGF-I receptor in sections of human skin is needed. Therefore, we now report an immunocytochemical and in situ hybridization localization study of the cell types expressing IGF-I and its receptor in human adult skin and its appendages. We have observed that (i) dermal fibroblasts produce IGF-I, (ii) the epidermal basal keratinocytes are IGF-I negative but IGF-I receptor positive, and (iii) the keratinocytes of the stratum granulosum produce IGF-I. These observations indicate either that the mitogenesis of the basal keratinocytes is regulated by IGF-I expressed both in the dermis and in the stratum granulosum, or that dermal fibroblasts are responsible for sequestering IGF-I to the basal keratinocytes and that the stratum granulosum-derived IGF-I may be an autocrine regulator of epidermal differentiation. The distribution of IGF-I and its receptor in the hair follicle indicates that IGF-I may be a morphogen, not a mitogen, at those sites, because their proliferating cells, but not their differentiating cells, are IGF-I receptor negative. Further, IGF-I receptor expression by the dermal papilla appears to be switched off during the transition from anagen to catagen, which implies a regulatory role for IGF-I during the hair growth cycle.


Assuntos
Fator de Crescimento Insulin-Like I/fisiologia , Mitógenos/fisiologia , Pele/citologia , Adulto , Animais , Diferenciação Celular , Regulação para Baixo , Feminino , Folículo Piloso/química , Humanos , Fator de Crescimento Insulin-Like I/análise , Fator de Crescimento Insulin-Like I/genética , Camundongos , RNA Mensageiro/análise , Receptor IGF Tipo 1/análise
18.
J Clin Endocrinol Metab ; 83(12): 4310-3, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9851769

RESUMO

Mutations in the RET proto-oncogene, which encodes a receptor tyrosine kinase, are associated with the pathogenesis of medullary thyroid carcinoma (MTC). Somatic mutations in RET, predominantly at codon 918, and very rarely at codon 883, have been found in a proportion of sporadic MTC. We have previously shown that approximately 80% of sporadic MTCs had at least one subpopulation with a somatic RET mutation. Uneven distribution of somatic mutation within a single tumor or among metastases from a single individual was notable. In the present study, we sought to correlate RET expression, as demonstrated by RET immunohistochemistry, with mutation status in sporadic MTC for each tumor. Seventy evaluable subpopulations, belonging to 28 unrelated sporadic cases, comprising primary MTC and metastases, were immunostained with two different polyclonal antibodies raised against the C-terminus of RET. The regional presence of codon 918 or 883 seemed to coincide with increased RET immunopositivity in at least 62 of 70 (89%, P < 0.000001) tumor subpopulations. The reasons for this concordance are not entirely clear but could be related to either RNA or protein stability. Preliminary studies have suggested that the presence of somatic codon 918 mutation in MTC has a prognostic significance. If these preliminary results prove true, then given our data, we can further explore the feasibility of RET immunocytochemistry as a rapid assessment for the presence of somatic codon 918 for molecular diagnostic and prognostic purposes.


Assuntos
Carcinoma Medular/genética , Carcinoma Medular/metabolismo , Proteínas de Drosophila , Mutação/fisiologia , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo , Receptores Proteína Tirosina Quinases/genética , Receptores Proteína Tirosina Quinases/metabolismo , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Carcinoma Medular/patologia , Carcinoma Medular/secundário , Humanos , Imuno-Histoquímica , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-ret , Neoplasias da Glândula Tireoide/patologia
19.
J Clin Endocrinol Metab ; 84(11): 4232-8, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10566678

RESUMO

A sharp increase in the incidence of pediatric thyroid papillary cancer was documented after the Chernobyl power plant explosion. An increased prevalence of rearrangements of the RET protooncogene (RET/PTC rearrangements) has been reported in Belarussian post-Chernobyl papillary carcinomas arising between 1990 and 1995. We analyzed 67 post-Chernobyl pediatric papillary carcinomas arising in 1995-1997 for RET/PTC activation: 28 were from Ukraine and 39 were from Belarus. The study, conducted by a combined immunohistochemistry and RT-PCR approach, demonstrated a high frequency (60.7% of the Ukrainian and 51.3% of the Belarussian cases) of RET/PTC activation. A strong correlation was observed between the solid-follicular subtype of papillary carcinoma and the RET/PTC3 isoform: 19 of the 24 RET/PTC-positive solid-follicular carcinomas harbored a RET/PTC3 rearrangement, whereas only 5 had a RET/PTC1 rearrangement. Taken together these results support the concept that RET/PTC activation plays a central role in the pathogenesis of thyroid papillary carcinomas in both Ukraine and Belarus after the Chernobyl accident.


Assuntos
Carcinoma Papilar/genética , Proteínas de Drosophila , Rearranjo Gênico , Centrais Elétricas , Proteínas Proto-Oncogênicas/genética , Liberação Nociva de Radioativos , Receptores Proteína Tirosina Quinases/genética , Neoplasias da Glândula Tireoide/genética , Adolescente , Criança , Feminino , Humanos , Masculino , Proteínas Proto-Oncogênicas c-ret , República de Belarus , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ucrânia
20.
Clin Pharmacol Ther ; 61(3): 340-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9084459

RESUMO

BACKGROUND: Ulcerative colitis is largely a disease of nonsmokers, and transdermal nicotine is of therapeutic value in the active disease. Because side effects are common, we developed a topical enema formulation of nicotine. OBJECTIVE: To study the pharmacokinetics of nicotine complexed with a polyacrylic carbomer and administered by enema to eight healthy volunteers and to eight patients with active ulcerative colitis, verified sigmoidoscopically. PATIENTS AND METHODS: All 16 subjects were nonsmokers. The mean age for normal subjects was 33 years; the mean for patients with ulcerative colitis was 60 years. Median stool frequency for patients with ulcerative colitis was four daily. Patients were taking 5-amino salicylic acid compounds and five were taking oral prednisolone (median dose, 12 mg daily). Nicotine, 6 mg, complexed with carbomer 974P, 400 mg, was administered in a 100 ml enema after an overnight fast, with serial blood measurements taken over 8 hours. Serum nicotine and cotinine were measured by gas liquid chromatography. Area under the concentration-time curves were calculated by the trapezoidal method, and the terminal elimination half-life was derived by extrapolation of the log-linear terminal phase. RESULTS: With the exception of nicotine time to reach peak concentration, which was longer in patients (median of 60 minutes compared with 45 minutes; p < 0.005), other comparisons between normal subjects and patients showed no statistically significant difference, although there was considerable inter-subject variation. Maximum concentration of nicotine, 8.1 +/- 3.5 ng/ml, in the 16 subjects occurred after a median of 60 minutes (range, 30 to 180 minutes); maximum cotinine concentrations of 60.4 +/- 11.5 ng/ml occurred after 4 hours. Side effects in five subjects were mild (four subjects) or moderate (one subject) and included lightheadedness, nausea, and headache; these five subjects were female lifelong nonsmokers of low body weight. CONCLUSION: Because most of the active ingredient of nicotine is converted to continine on the first pass through the liver, substantial concentrations can be achieved at the site of disease with only modest rises in serum nicotine, which are responsible for side effects; cotinine has low pharmacologic activity. Topical administration of nicotine may be useful treatment for distal ulcerative colitis.


Assuntos
Colite Ulcerativa/sangue , Nicotina/administração & dosagem , Nicotina/farmacocinética , Resinas Acrílicas , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Estudos de Casos e Controles , Colite Ulcerativa/tratamento farmacológico , Cotinina/sangue , Portadores de Fármacos , Enema , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/sangue , Nicotina/química , Polivinil , Fatores de Tempo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA