RESUMO
Non-ionizing radiation at 2.45 GHz may modify the morphology and expression of genes that codify heat shock proteins (HSP) in the thyroid gland. Diathermy is the therapeutic application of non-ionizing radiation to humans for its beneficial effects in rheumatological and musculo-skeletal pain processes. We used a diathermy model on laboratory rats subjected to maximum exposure in the left front leg, in order to study the effects of radiation on the nearby thyroid tissue. Fifty-six rats were individually exposed once or repeatedly (10 times in two weeks) for 30 min to 2.45 GHz radiation in a commercial chamber at different non-thermal specific absorption rates (SARs), which were calculated using the finite difference time domain technique. We used immunohistochemistry methods to study the expression of HSP-90 and morphological changes in thyroid gland tissues. Ninety minutes after radiation with the highest SAR, the central and peripheral follicles presented increased size and the thickness of the peripheral septa had decreased. Twenty-four hours after radiation, only peripheral follicles radiated at 12 W were found to be smaller. Peripheral follicles increased in size with repeated exposure at 3 W power. Morphological changes in the thyroid tissue may indicate a glandular response to acute or repeated stress from radiation in the hypothalamic-pituitary-thyroid axis. Further research is needed to determine if the effect of this physical agent over time may cause disease in the human thyroid gland.
Assuntos
Proteínas de Choque Térmico HSP90/metabolismo , Micro-Ondas/efeitos adversos , Glândula Tireoide/patologia , Glândula Tireoide/efeitos da radiação , Animais , Biomarcadores/metabolismo , Diatermia/efeitos adversos , Feminino , Humanos , Imuno-Histoquímica , Ratos , Ratos Sprague-Dawley , Glândula Tireoide/metabolismo , Fatores de Tempo , Distribuição TecidualRESUMO
CONTEXT: Mechanisms of thyroid physiology and cancer are principally studied in follicular cell lines. However, human thyroid cancer lines were found to be heavily contaminated by other sources, and only one supposedly normal-thyroid cell line, immortalized with SV40 antigen, is available. In primary culture, human follicular cultures lose their phenotype after passage. We hypothesized that the loss of the thyroid phenotype could be related to culture conditions in which human cells are grown in medium optimized for rodent culture, including hormones with marked differences in its affinity for the relevant rodent/human receptor. OBJECTIVE: The objective of the study was to define conditions that allow the proliferation of primary human follicular thyrocytes for many passages without losing phenotype. METHODS: Concentrations of hormones, transferrin, iodine, oligoelements, antioxidants, metabolites, and ethanol were adjusted within normal homeostatic human serum ranges. Single cultures were identified by short tandem repeats. Human-rodent interspecies contamination was assessed. RESULTS: We defined an humanized 7 homeostatic additives medium enabling growth of human thyroid cultures for more than 20 passages maintaining thyrocyte phenotype. Thyrocytes proliferated and were grouped as follicle-like structures; expressed Na+/I- symporter, pendrin, cytokeratins, thyroglobulin, and thyroperoxidase showed iodine-uptake and secreted thyroglobulin and free T3. Using these conditions, we generated a bank of thyroid tumors in culture from normal thyroids, Grave's hyperplasias, benign neoplasms (goiter, adenomas), and carcinomas. CONCLUSIONS: Using appropriate culture conditions is essential for phenotype maintenance in human thyrocytes. The bank of thyroid tumors in culture generated under humanized humanized 7 homeostatic additives culture conditions will provide a much-needed tool to compare similarly growing cells from normal vs pathological origins and thus to elucidate the molecular basis of thyroid disease.
Assuntos
Técnicas de Cultura de Células , Meios de Cultura , Glândula Tireoide/citologia , Neoplasias da Glândula Tireoide/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Fenótipo , Ratos , Tireoglobulina/metabolismo , Tri-Iodotironina/metabolismoRESUMO
Non-ionizing radiation at 2.45â GHz may modify the expression of genes that codify heat shock proteins (HSP) in the thyroid gland. Using the enzyme-linked immunosorbent assay (ELISA) technique, we studied levels of HSP-90 and HSP-70. We also used hematoxilin eosin to look for evidence of lesions in the gland and applied the DAPI technique of fluorescence to search for evidence of chromatin condensation and nuclear fragmentation in the thyroid cells of adult female Sprague-Dawley rats. Fifty-four rats were individually exposed for 30â min to 2.45â GHz radiation in a Gigahertz transverse electromagnetic (GTEM) cell at different levels of non-thermal specific absorption rate (SAR), which was calculated using the finite difference time domain (FDTD) technique. Ninety minutes after radiation, HSP-90 and HSP-70 had decreased significantly (P<0.01) after applying a SAR of 0.046±1.10â W/Kg or 0.104±5.10(-3)â W/Kg. Twenty-four hours after radiation, HSP-90 had partially recovered and HSP-70 had recovered completely. There were few indications of lesions in the glandular structure and signs of apoptosis were negative in all radiated animals. The results suggest that acute sub-thermal radiation at 2.45â GHz may alter levels of cellular stress in rat thyroid gland without initially altering their anti-apoptotic capacity.
RESUMO
BACKGROUND: Several authors have reported results obtained with the microendoscopic diskectomy (MED) technique, but the long-term outcome has not been described. This report summarizes our clinical experience with the lumbar MED technique with a long-term follow-up period. OBJECTIVE: To evaluate the efficacy of the MED for lumbar disk herniation and to report long-term outcome and complications (5-year follow-up). METHODS: One hundred twenty consecutive patients with lumbar disk herniation were treated with the METRx system.We included all types of lumbar herniated disks: contained, not contained, foraminal, and migrated disk herniations. The results were evaluated with the Visual Analog Scale (VAS) pain score, Oswestry Disability Index score, patient satisfaction questionnaire, and modified Macnab criteria. RESULTS: The average age of patients was 41 years; 65 were men and 55 were women. The most commonly affected level was L5-S1 (54.2%). The follow-up time after surgery was 5 years in all cases. We obtained good or excellent results in 75% of patients and regular results in 18%. Good subjective satisfaction was observed with surgery in 92% of patients. The mean decrease in the Oswestry Disability Index score was 52.8 ± 21.6; the mean decrease in leg VAS score was 6.1 ± 2.3; and the mean decrease in lumbar VAS score was 1.9 ± 3.3. Adjusted mean differences were statistically significant in all cases (P < .05). CONCLUSION: MED not only reduces the incision, tissue damage, and postoperative period of incapacity but also offers long-term results comparable to those of conventional techniques.
Assuntos
Discotomia/métodos , Endoscopia/métodos , Deslocamento do Disco Intervertebral/cirurgia , Microcirurgia/métodos , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Satisfação do Paciente , Recuperação de Função Fisiológica , Inquéritos e Questionários , Resultado do Tratamento , Adulto JovemRESUMO
Recently, it has been shown that commercial human thyroid lines were in fact derived from colon, mammary carcinoma, or melanoma. Others have demonstrated the absence of a common pattern of gene expression between available thyroid cancer cell lines and tumors from patients. Thus, it is important to use several primary cells with a common pathological origin to achieve reproducible results, and it is necessary to find common methods for manipulation of protein expression in such various cultures. We have standardized a transfection method for efficient expression of exogenous proteins in human primary thyroid cultures. We compared lipid-based techniques with three electroporation systems (Electroporator PulseAgile [PA]-4000, Microporator MP-100, and Nucleofector II). Nucleofection was unquestionably the most efficient even for promoter regulation studies, and it was effective in cultures from different origins as normal thyroid, papillary carcinoma, or lymphoid node metastasis. We also standardized, through lentiviral infection, the short hairpin RNA downregulation of protein expression generating human thyrocytes with low levels of p27KIP1 as a model system.
Assuntos
Proteínas/metabolismo , RNA/metabolismo , Glândula Tireoide/citologia , Células Cultivadas , Expressão Gênica , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos , Proteínas/genética , RNA/genética , TransfecçãoRESUMO
OBJECTIVE: To evaluate the efficacy of radicular decompression in lumbar spinal stenosis using a microendoscopic technique. METHODS: This was a longitudinal prospective study of 50 patients with a diagnosis of lumbar spinal stenosis who were treated by microendoscopic decompression using an 18-mm METRx tubular retractor according to the METRx technique (Medtronic Sofamor Danek, Memphis, TN). Twenty of the patients had an additional disc prolapse, and a microendoscopic discectomy was associated with decompressive laminectomy. The results were evaluated using the visual analog scale pain score, Oswestry Disability Index score, patient satisfaction questionnaire, and modified Macnab classification. RESULTS: The average age of the patients was 56 years; 29 (58%) were men and 21 (42%) were women. The most commonly affected level was L4-L5 (64%). The mean surgical intervention time was 94.3 (+/- 14.3) minutes. Mean postoperative hospital stay was 3.16 (+/- 2.3) days. The follow-up time after surgery was 4 years (48 +/- 6.6 months; range, 24-72 months). We obtained good or excellent results in 72% of patients, achieving good subjective satisfaction in 68% of the patients. The mean decrease in the Oswestry Disability Index score was 30.23 (+/- 24.29), the mean decrease in the leg pain visual analog scale score was 6.02 (+/- 2.57), and the mean decrease in the lumbar pain visual analog scale score was 0.84 (+/- 2.06). Adjusted mean differences were in all cases statistically significant (P < 0.05). CONCLUSION: Data indicate that, in our experience, on midterm follow-up, microendoscopic laminectomy decompression is an effective technique for the treatment of lumbar spinal stenosis.
Assuntos
Descompressão Cirúrgica/métodos , Laminectomia/métodos , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Estenose Espinal/cirurgia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Medição da Dor , Complicações Pós-Operatórias , Estudos Retrospectivos , Resultado do TratamentoRESUMO
This study investigated the effects of mobile-phone-type radiation on the cerebral activity of seizure-prone animals. When rats transformed into an experimental model of seizure-proneness by acute subconvulsive doses of picrotoxin were exposed to 2 h GSM-modulated 900 MHz radiation at an intensity similar to that emitted by mobile phones, they suffered seizures and the levels of the neuronal activity marker c-Fos in neocortex, paleocortex, hippocampus and thalamus increased markedly. Non-irradiated picrotoxin-treated rats did not suffer seizures, and their cerebral c-Fos counts were significantly lower. Radiation caused no such differences in rats that had not been pretreated with picrotoxin. We conclude that GSM-type radiation can induce seizures in rats following their facilitation by subconvulsive doses of picrotoxin, and that research should be pursued into the possibility that this kind of radiation may similarly affect brain function in human subjects with epileptic disorders.
Assuntos
Encéfalo/efeitos da radiação , Telefone Celular , Convulsivantes , Micro-Ondas/efeitos adversos , Picrotoxina , Proteínas Proto-Oncogênicas c-fos/metabolismo , Convulsões/etiologia , Convulsões/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Masculino , Ratos , Ratos Sprague-DawleyRESUMO
Undifferentiated (anaplastic) thyroid carcinoma is a highly aggressive human cancer with very poor prognosis. Although there have been a few studies of candidate treatments, the fact that it is an infrequent tumor makes it very difficult to design clinical trials. A strong association has been observed between undifferentiated thyroid carcinoma and TP53 mutations in numerous molecular genetic and expression studies. Plitidepsin (Aplidin, PharmaMar, Madrid, Spain) is a novel anticancer compound obtained from a sea tunicate. This compound has been reported to induce apoptosis independently of TP53 status. We investigated the actions of plitidepsin in human thyroid cancer cells. In initial experiments using primary cultured cells from a differentiated (papillary) carcinoma, we found that 100 nmol/L plitidepsin induced apoptosis, whereas lower doses were cytostatic. Because our aim was to study the effects of plitidepsin at clinically relevant concentrations, subsequent experiments were done with a dosage regimen reflecting plasma concentrations observed in previously reported clinical trials: 100 nmol/L for 4 hours, followed by 10 nmol/L for 20 hours (4(100)/20(10) plitidepsin). This plitidepsin dosage regimen blocked the proliferation of a primary undifferentiated/anaplastic thyroid carcinoma culture obtained in our laboratory and of a commercial cell line (8305C) obtained from an undifferentiated thyroid carcinoma; however, it did not induce apoptosis. The proportion of cells in the G(1) phase of the cell cycle was greatly increased and the proportion in the S/G(2)-M phases greatly reduced, suggesting that plitidepsin blocks G(1)-to-S transition. Levels of the cyclin D1/cyclin-dependent kinase 4/p21 complex proteins were decreased and, in line with this, the levels of unphosphorylated Rb1 increased. The decrease in cell cycle proteins correlated with hypoacetylation of histone H3. Finally, we did experiments to assess how rapidly tumor cells return to their initial pretreatment proliferative behavior after 4(100)/20(10) plitidepsin treatment. Cells from undifferentiated tumors needed more than 3 days to recover logarithmic growth, and after 7 days, cell number was still significantly lower than in control cultures. 4(100)/20(10) plitidepsin inhibited the growth in soft agar. Together, our data show that plitidepsin is able to block in vitro cell cycle progression at concentrations similar to serum concentrations observed in vivo, and that this effect is persistent for several days after plitidepsin removal. Whether plitidepsin will prove to be clinically useful in the treatment of undifferentiated thyroid cancers remains to be established. However, our results raise the possibility that plitidepsin might be effective alone or in combination with radiotherapy and/or other drug treatments.
Assuntos
Antineoplásicos/farmacologia , Carcinoma/metabolismo , Depsipeptídeos/farmacologia , Regulação Neoplásica da Expressão Gênica , Neoplasias da Glândula Tireoide/metabolismo , Adulto , Ágar/química , Idoso , Apoptose , Carcinoma/patologia , Ciclo Celular , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Ensaios Clínicos como Assunto , Depsipeptídeos/química , Relação Dose-Resposta a Droga , Feminino , Citometria de Fluxo , Genes p53 , Células HeLa , Histonas/metabolismo , Humanos , Immunoblotting , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Peptídeos Cíclicos , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Fatores de Tempo , Células Tumorais Cultivadas , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
Millions of people worldwide suffer goiter, a proliferative disease of the follicular cells of the thyroid that may become neoplastic. Thyroid neoplasms have low proliferative index, low apoptotic index and a high incidence of metastasis. TGF-beta is overexpressed in thyroid follicular tumor cells. To investigate the role of TGF-beta in thyroid tumor progression, we established cultures of human thyrocytes from different proliferative pathologies (Grave's disease, multinodular goiter, follicular adenoma, papillary carcinoma), lymph node metastasis, and a normal thyroid sample. All cultures maintained the thyrocyte phenotype. TGF-beta induced cell-cycle arrest in all cultures, in contrast with results reported for other epithelial tumors. In deprived medium, TGF-beta induced apoptosis in normal thyrocyte cultures and all neoplastic cultures except the metastatic cultures. This apoptosis was mediated by a reduction in p27kip1 levels, inducing cell-cycle initiation. Antisense p27 expression induced apoptosis in the absence of TGF-beta. By contrast, in cells in which p27 was overexpressed, TGF-beta had a survival effect. In growth medium, a net survival effect occurs in neoplastic thyrocytes only, not normal thyrocytes, due to activation of the NF-kappaB survival program. Together, these findings suggest that (a) thyroid neoplasms are due to reduced apoptosis, not increased division, in line with the low proliferative index of these pathologies, and (b) TGF-beta induces apoptosis in normal thyrocytes via p27 reduction, but that in neoplastic thyrocytes this effect is overridden by activation of the NF-kappaB program.
Assuntos
Apoptose/efeitos dos fármacos , Proteínas de Ciclo Celular/fisiologia , NF-kappa B/fisiologia , Glândula Tireoide/citologia , Neoplasias da Glândula Tireoide/patologia , Fator de Crescimento Transformador beta/farmacologia , Proteínas Supressoras de Tumor/fisiologia , Proteínas de Ciclo Celular/análise , Divisão Celular , Células Cultivadas , Inibidor de Quinase Dependente de Ciclina p27 , Humanos , Metástase Neoplásica , Fenótipo , Proteínas Supressoras de Tumor/análiseRESUMO
OBJECTIVE: The clinicopathological features of gastrointestinal (GI) stromal tumours were analysed to find out the features that influence prognosis in these neoplasms. DESIGN: Retrospective study. SETTING: University Hospital, Spain. SUBJECTS: Review of clinical records and analysis of a series of GI stromal tumours classified in three groups: benign = 7 leiomyomas, malignant or potentially malignant = 16 combined smooth muscle-neural tumours, and 2 miscellaneous, and definitely malignant = 1 leiomyosarcoma and 8 gastrointestinal autonomic nerve tumours. MAIN OUTCOME MEASURES: Electron microscopy and immunohistochemical staining for vimentin, smooth muscle actin, muscle specific actin, desmin, S-100 protein, neuronal specific enolase, chromogranin A, synaptophysin, CD34, CD117 (c-kit), Bcl-2, and Ki-67. RESULTS: We found significant differences (p < 0.0001) between the median (P25, P75) size of tumours in the benign group 2.0 (1.2, 3.5) and in the potentially 7.5 (4.0, 13.0) and definitely 5.0 (4.0,6.5) malignant groups. The percentage of mitoses was lower (p = 0.003) in the benign group 0.4 (0.5) than in the other groups 2.0 (1.0, 5.0). Immunoreactivity for CD117 in leiomyomas was an unexpected finding; this showed a different staining pattern from the diffuse and homogeneous staining in GI stromal tumours. In addition, the MIB-1 proliferation index differentiated (p = 0.002) between the benign group 1.5 (1.0, 2.5) and the other two groups 7.0 (3.0, 11.0). CONCLUSIONS: These findings support the idea that GI stromal tumours form a heterogeneous group of neoplasms in which large size, presence of necrosis, and a high proliferative index (mitotic rate or MIB-1 index, or both) are good predictors of malignant behaviour.
Assuntos
Neoplasias Gastrointestinais/patologia , Leiomioma/patologia , Leiomiossarcoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Neoplasias Gastrointestinais/metabolismo , Humanos , Imuno-Histoquímica , Leiomioma/metabolismo , Leiomioma Epitelioide/metabolismo , Leiomioma Epitelioide/patologia , Leiomiossarcoma/metabolismo , Masculino , Pessoa de Meia-Idade , Índice Mitótico , Necrose , Estudos RetrospectivosRESUMO
El presente estudio se realizó con el fin de evaluar la relación entre vasoespasmo (VE) cerebral y el deterioro clínico posterior a la angiografía, en pacientes con hemorragia subaracnoidea (HSA). Se analizaron los estudios tomográficos y angiográficos de 46 enfermos con diagnóstico de hemorragia subaracnoidea (HSA). La frecuencia del VE fue del 45.6%con predominio en el sexo femenino (71.4%). Entre los pacientes que mostraron infarto cerebral, el VEse encontró en el 70%de los casos. En seis de siete enfermos que presentaron deterioro clínico posterior a la angiografía, se encontró VE. Por lo anterior, concluimos que el VE es un factor importante en el deterioro postangiográfico de los enfermos con HSA. Por lo tanto nosotros consideramos que: los estudios angiográficos en pacientes con HSA deberán realizarse, de preferencia fuera del tiempo en el que el VE se presenta con mayor frecuencia (antes del tercero, y después del décimo día de evolución).