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1.
Parasite Immunol ; 37(4): 171-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25545318

RESUMO

Age-associated alterations of Th2 immune responses against nematode parasites are largely unknown. We investigated primary and memory responses against two types of gastrointestinal nematode parasites, Heligmosomoides polygyrus (Hp) and Nippostrongylus brasiliensis (Nb), in aged mice. The small intestinal gene expression of Th2 cytokines was almost unchanged after primary (Nb and Hp) and secondary infection (Hp) in aged mice in contrast to strongly increased small intestinal gene expression of Th2 cytokines in young (3-month-old) mice. Mucus production decreased (Nb), and worm expulsion was impaired (Nb and Hp) compared with the young mice. Immunofluorescent staining revealed that after Hp infection, the number of alternatively activated macrophages, which are induced by Th2 cytokines, was lower in the aged mice. On the other hand, the number of CD4(+) T cells recruited to the worm cysts was normal compared with the young mice. These results suggest that migration of CD4(+) T cells to the host-parasite interface is not affected by ageing. Alterations in Th2 immune responses in aged mice might be due to inappropriate or insufficient activation of CD4(+) T cells in the submucosa.


Assuntos
Envelhecimento/imunologia , Enteropatias Parasitárias/imunologia , Nematospiroides dubius/fisiologia , Nippostrongylus/fisiologia , Infecções por Strongylida/imunologia , Animais , Citocinas/metabolismo , Feminino , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/patologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções por Strongylida/epidemiologia , Infecções por Strongylida/patologia , Células Th2/imunologia
2.
Radiat Res ; 199(6): 583-590, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-37057978

RESUMO

Translocation analysis using fluorescence in situ hybridization (FISH) is the method of choice for dose assessment in case of chronic or past exposures to ionizing radiation. Although it is a widespread technique, unlike dicentrics, the number of FISH-based inter-laboratory comparisons is small. For this reason, although the current Running the European Network of Biological and Physical retrospective Dosimetry (RENEB) inter-laboratory comparison 2021 was designed as a fast response to a real emergency scenario, it was considered a good opportunity to perform an inter-laboratory comparison using the FISH technique to gain further experience. The Bundeswehr Institute of Radiobiology provided peripheral blood samples from one healthy human volunteer. Three test samples were irradiated with blinded doses of 0, 1.2, and 3.5 Gy, respectively. Samples were then sent to the seven participating laboratories. The FISH technique was applied according to the standard procedure of each laboratory. Both, the frequency of translocations and the estimated dose for each sample were sent to the coordinator using a special scoring sheet for FISH. All participants sent their results in due time. However, although it was initially requested to send the results based on the full analysis, evaluating 500 equivalent cells, most laboratories only sent the results based on triage, with a smaller number of analyzed cells. In the triage analysis, there was great heterogeneity in the number of equivalent cells scored. On the contrary, for the full analysis, this number was more homogeneous. For all three samples, one laboratory showed outlier yields compared to the other laboratories. Excluding these results, in the triage analysis, the frequency of translocations in sample no. 1 ranged from 0 to 0.013 translocations per cell, and for samples no. 2 and no. 3 the genomic mean frequency were 0.27 ± 0.03 and 1.47 ± 0.14, with a coefficient of variation of 0.29 and 0.23 respectively. Considering only results obtained in the triage analysis for sample no. 1, all laboratories, except one, classified this sample as the non-irradiated one. For sample no. 2, excluding the outlier value, the mean reported dose was 1.74 ± 0.16 Gy indicating a mean deviation of about 0.5 Gy to the delivered dose of 1.2 Gy. For sample no. 3 the mean dose estimated was 4.21 ± 0.21 Gy indicating a mean deviation of about 0.7 Gy to the delivered dose of 3.5 Gy. In the frame of RENEB, this is the second FISH-based inter-laboratory comparison. The whole exercise was planned as a response to an emergency, therefore, a triage analysis was requested for all the biomarkers except for FISH. Although a full analysis was initially requested for FISH, most of the laboratories reported only a triage-based result. The main reason is that it was not clearly stated what was required before starting the exercise. Results show that most of the laboratories successfully discriminated unexposed and irradiated samples from each other without any overlap. A good agreement in the observed frequencies of translocations was observed but there was a tendency to overestimate the delivered doses. Efforts to improve the harmonization of this technique and subsequent exercises to elucidate the reason for this trend should be promoted.


Assuntos
Radiometria , Translocação Genética , Humanos , Hibridização in Situ Fluorescente/métodos , Estudos Retrospectivos , Radiometria/métodos , Bioensaio/métodos , Aberrações Cromossômicas
3.
Radiat Meas ; 46(9): 923-928, 2011 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-21949482

RESUMO

Biological dosimetry is an essential tool for estimating radiation doses received to personnel when physical dosimetry is not available or inadequate. The current preferred biodosimetry method is based on the measurement of radiation-specific dicentric chromosomes in exposed individuals' peripheral blood lymphocytes. However, this method is labour-, time- and expertise-demanding. Consequently, for mass casualty applications, strategies have been developed to increase its throughput. One such strategy is to develop validated cytogenetic biodosimetry laboratory networks, both national and international. In a previous study, the dicentric chromosome assay (DCA) was validated in our cytogenetic biodosimetry network involving five geographically dispersed laboratories. A complementary strategy to further enhance the throughput of the DCA among inter-laboratory networks is to use a triage DCA where dose assessments are made by truncating the labour-demanding and time-consuming metaphase-spread analysis to 20 to 50 metaphase spreads instead of routine 500 to 1000 metaphase spread analysis. Our laboratory network also validated this triage DCA, however, these dose estimates were made using calibration curves generated in each laboratory from the blood samples irradiated in a single laboratory. In an emergency situation, dose estimates made using pre-existing calibration curves which may vary according to radiation type and dose rate and therefore influence the assessed dose. Here, we analyze the effect of using a pre-existing calibration curve on assessed dose among our network laboratories. The dose estimates were made by analyzing 1000 metaphase spreads as well as triage quality scoring and compared to actual physical doses applied to the samples for validation. The dose estimates in the laboratory partners were in good agreement with the applied physical doses and determined to be adequate for guidance in the treatment of acute radiation syndrome.

4.
Radiat Prot Dosimetry ; 186(1): 139-142, 2019 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-30576530

RESUMO

In 2015, the Asian Radiation Dosimetry Group established a regional network of biological dosimetry laboratories known as the ARADOS-WG03 (Working Group 03; Biological Dosimetry). A survey was conducted in 2017 to evaluate the capabilities and capacities of the participating laboratories for emergency preparedness and responses in large-scale nuclear and/or radiological incidents. The results of this survey were identified and assessed. The data provide important information on the current state of emergency cytogenetic biological dosimetry capabilities in the Asian region.


Assuntos
Bioensaio/métodos , Defesa Civil/organização & administração , Planejamento em Desastres/organização & administração , Laboratórios/organização & administração , Exposição à Radiação/efeitos adversos , Liberação Nociva de Radioativos/prevenção & controle , Radiometria/métodos , Ásia , Análise Citogenética , Sistemas Inteligentes , Humanos , Laboratórios/normas , Proteção Radiológica/métodos , Proteção Radiológica/normas
5.
Radiat Prot Dosimetry ; 182(1): 128-138, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30423161

RESUMO

Biological dosimetry enables individual dose reconstruction in the case of unclear or inconsistent radiation exposure situations, especially when a direct measurement of ionizing radiation is not or is no longer possible. To be prepared for large-scale radiological incidents, networking between well-trained laboratories has been identified as a useful approach for provision of the fast and trustworthy dose assessments needed in such circumstances. To this end, various biodosimetry laboratories worldwide have joined forces and set up regional and/or nationwide networks either on a formal or informal basis. Many of these laboratories are also a part of global networks such as those organized by World Health Organization, International Atomic Energy Agency or Global Health Security Initiative. In the present report, biodosimetry networks from different parts of the world are presented, and the partners, activities and cooperation actions are detailed. Moreover, guidance for situational application of tools used for individual dosimetry is given.


Assuntos
Planejamento em Desastres/organização & administração , Lesões por Radiação/prevenção & controle , Monitoramento de Radiação/métodos , Proteção Radiológica/métodos , Liberação Nociva de Radioativos/prevenção & controle , Radiometria/métodos , Humanos , Agências Internacionais , Radiação Ionizante
6.
J Comp Pathol ; 137(2-3): 133-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17645889

RESUMO

A case of epithelioid variant of liposarcoma in a 31-month-old Japanese Black heifer is described. The tumour mass, which formed in the subcutis of the left cheek, was excised surgically, but this was followed by recurrence and metastasis to lymph nodes. The primary tumour was composed of sheets of lipid-laden cells, and anaplastic larger cells with eosinophilic or amphophilic cytoplasm were occasionally seen. In addition to vimentin and S-100 protein expression in the majority of tumour cells, squamous and non-squamous cytokeratins (CKs) were present, mainly in the larger cells, which predominated in the metastatic lesions. The expression of CKs was considered to be evidence of epithelioid differentiation.


Assuntos
Doenças dos Bovinos/patologia , Lipossarcoma/veterinária , Neoplasias Epiteliais e Glandulares/veterinária , Neoplasias Cutâneas/veterinária , Animais , Bovinos , Doenças dos Bovinos/metabolismo , Bochecha , Feminino , Queratinas/metabolismo , Lipossarcoma/metabolismo , Lipossarcoma/patologia , Neoplasias Epiteliais e Glandulares/metabolismo , Neoplasias Epiteliais e Glandulares/patologia , Proteínas S100/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia , Vimentina/metabolismo
7.
Leukemia ; 15(8): 1193-202, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11480561

RESUMO

During fluorescence in situ hybridization (FISH) analysis of metaphase cells from 70 patients with lymphoid and myeloid hematologic malignancies and chromosomal rearrangements involving band 12p13, we identified nine patients (four with lymphoid malignancies, four with myeloid malignancies and one with biphenotypic leukemia) who showed more complicated rearrangements than we had expected from conventional cytogenetic study. In six patients, multiple breaks occurred in small segments of 12p with subsequent translocations and insertions of these segments into other chromosomes, sometimes to unexpected regions. In three patients additional chromosome breaks resulted in a sub-clone which was cytogenetically indistinguishable from the main clone in each patient based on the cytogenetic analysis. These subtle molecular events were detected exclusively in a region covering TEL/ETV6 and KIP1/CDKN1B. Seven of nine had a previous history of chemo/radiotherapy; all the patients showed complex karyotypes, even though they were newly diagnosed with leukemia. Survival data were available in five patients, and all survived less than 6 months. These findings suggest that the 12p13 region, especially the above-mentioned region, is genetically unstable and fragile. It is likely that multiple chromosome breaks were induced through mutagens used in chemo/ radiotherapy, and are associated with a sub-group of patients with an extremely bad prognosis.


Assuntos
Fragilidade Cromossômica , Cromossomos Humanos Par 12 , Neoplasias Hematológicas/genética , Rearranjo Gênico , Humanos
8.
Leukemia ; 12(7): 1119-27, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9665199

RESUMO

A new cell line with megakaryoblastic features, designated UoC-M1, was established from the malignant cells of a 68-year-old patient with acute myeloid leukemia. The patient's leukemic cells reacted with alpha-naphthyl acetate esterase and acid phosphatase and expressed CD7, CD24, CD34, CD38, CD45, HLA-DR and CD61. Cytogenetic analysis of the patient's malignant cells (and of the UoC-M1 cells) showed a human, male hypodiploid karyotype with many chromosome rearrangements and marker chromosomes. Spectral karyotyping (SKY) analysis complemented the G-banded karyotyping and clarified several chromosomal translocations and identified the marker chromosomes. Fluorescence in situ hybridization (FISH) and SKY analysis demonstrated that one marker chromosome contained three segments of chromosome 9 interspersed with three segments of chromosome 11, as well as a portion of chromosome 19. FISH analysis with a probe for MLL revealed that the UoC-M1 cells contained four copies of the MLL gene. Southern blot analysis determined that the MLL gene had a germline profile while Northern and Western analyses showed that the MLL mRNAs and protein were of the appropriate sizes. This is the first report of amplification of the MLL gene which may be an additional mechanism of leukemogenesis or disease progression.


Assuntos
Proteínas de Ligação a DNA/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Megacariócitos/citologia , Proto-Oncogenes , Fatores de Transcrição , Células Tumorais Cultivadas , Idoso , Northern Blotting , Southern Blotting , Western Blotting , Amplificação de Genes , Rearranjo Gênico , Histona-Lisina N-Metiltransferase , Humanos , Imunofenotipagem , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Megacariócitos/fisiologia , Microscopia Eletrônica , Proteína de Leucina Linfoide-Mieloide
10.
Gene ; 275(1): 31-7, 2001 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-11574149

RESUMO

In order to isolate genes that may not be represented in current human brain cDNA libraries, we have sequenced about 20,000 sequence tags of cDNA clones derived from cerebellum and parietal lobe of cynomolgus monkeys (Macaca fascicularis). We determined the entire cDNA sequence of approximately 700 clones whose 5'-terminal sequences showed no homology to annotated putative genes or expressed sequence tags in current databases of genetic information. From this, 118 clones with sequences encoding novel open reading frames of more than 100 amino acid residues were selected for further analysis. To localize the genes corresponding to these 118 newly identified cDNA clones on human chromosomes, we performed a homology search using the human genome sequence and fluorescent in situ hybridization. In total, 108 of 118 clones were successfully assigned to specific regions of human chromosomes. This result demonstrates that genes expressed in cynomolgus monkey are highly conserved throughout primate evolution, and that virtually all had human homologs. Furthermore, we will be able to discover novel human genes in the human genome using monkey homologs as probes.


Assuntos
Encéfalo/metabolismo , Cromossomos Humanos/genética , DNA Complementar/genética , Macaca fascicularis/genética , Animais , Mapeamento Cromossômico , DNA Complementar/química , Feminino , Biblioteca Gênica , Genoma Humano , Humanos , Hibridização in Situ Fluorescente , Masculino , Dados de Sequência Molecular , Análise de Sequência de DNA
11.
Cytogenet Genome Res ; 101(2): 161-5, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14610358

RESUMO

The Rhesus (Rh) blood group system in humans is encoded by two genes with high sequence homology. These two genes, namely, RHCE and RHD, have been implied to be duplicated during evolution. However, the genomic organization of Rh genes in chimpanzees and other nonhuman primates has not been precisely studied. We analyzed the arrangement of the Rh genes of chimpanzees (Pan troglodytes) by two-color fluorescence in situ hybridization on chromatin DNA fibers (fiber-FISH) using two genomic DNA probes that respectively contain introns 3 and 7 of human RH genes. Among the five chimpanzees studied, three were found to be homozygous for the two-Rh-gene type, in an arrangement of Rh (5'-->3') - Rh (3'<--5'). Although a similar gene arrangement can be detected in the RH gene locus of typical Rh-positive humans, the distance between the two genes in chimpanzees was about 50 kb longer than that in humans. The remaining two chimpanzees were homozygous for a four-Rh-gene type, in an arrangement of Rh (5'-->3') - Rh (3'<--5') - Rh (3'<--5') - Rh (3'<--5') within a region spanning about 300 kb. This four-Rh-gene type has not been detected in humans. Further analysis of other great apes showed different gene arrangements: a bonobo was homozygous for the three-Rh-gene type; a gorilla was heterozygous for the one-Rh- and two-Rh-gene types; an orangutan was homozygous for the one-Rh-gene type. Our findings on the intra- and interspecific genomic variations in the Rh gene locus in Hominoids would shed further light on reconstructing the genomic pathways of Rh gene duplication during evolution.


Assuntos
Ordem dos Genes , Pan troglodytes/genética , Sistema do Grupo Sanguíneo Rh-Hr/genética , Animais , Mapeamento Cromossômico/métodos , Sondas de DNA , Evolução Molecular , Hominidae/genética , Humanos , Hibridização in Situ Fluorescente/métodos , Íntrons
12.
J Nucl Med ; 37(6): 997-9, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8683332

RESUMO

Findings for focal accumulation of 123I-15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid ([123I]BMIPP) in a patient with liposarcoma of the thigh are presented. Iodine-123-BMIPP accumulated heterogeneously in the liposarcoma. The region with marked accumulation of [123I]BMIPP was diagnosed as mixoid liposarcoma. The region with little accumulation of [123I]BMIPP was diagnosed as well-differentiated liposarcoma. Differences in the accumulation of [123I]BMIPP may reflect differences in fatty acid metabolism between histopathological types of liposarcoma.


Assuntos
Ácidos Graxos , Radioisótopos do Iodo , Iodobenzenos , Lipossarcoma/diagnóstico por imagem , Coxa da Perna , Adulto , Humanos , Lipossarcoma/diagnóstico , Imageamento por Ressonância Magnética , Masculino , Cintilografia
13.
Cancer Genet Cytogenet ; 97(2): 157-60, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9283600

RESUMO

Using probes located between 12p12.1 and 12p13.3, we performed fluorescence in situ hybridization (FISH) analysis and identified an inv(12)(p13.1q11) in a patient with acute myeloid leukemia (AML-M6). Standard cytogenetic analysis had identified the rearranged chromosomes 12 as del(12) (p11p13). Although deletions and translocations involving band 12p13 are fairly common chromosomal abnormalities observed in a broad spectrum of hematologic malignancies, inv(12) is a rather rare abnormality. We compare the clinical and cytogenetic findings with those of the previous cases reported in the literature.


Assuntos
Inversão Cromossômica , Cromossomos Humanos Par 12 , Leucemia Eritroblástica Aguda/genética , Bandeamento Cromossômico , Mapeamento Cromossômico , Sondas de DNA , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Pessoa de Meia-Idade
14.
J Gastroenterol ; 30(6): 783-5, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8963399

RESUMO

Intrahepatic and/or extrahepatic collateral pathways result from the membranous obstruction of the inferior vena cava. These collaterals are usually insufficient to prevent Budd-Chiari syndrome. We reprot an unusual case of asymptomatic membranous obstruction of the inferior vena cava in which marked intrahepatic collateral pathways were formed. Although the inferior vena cava terminated above the orifice of the right hepatic vein, the middle and left hepatic veins were patent above the membrane, without narrowing. Blood from the inferior vena cava drained into the right atrium via the intrahepatic collaterals between the right and middle hepatic veins without resistance.


Assuntos
Síndrome de Budd-Chiari/diagnóstico , Circulação Colateral/fisiologia , Fígado/irrigação sanguínea , Veia Cava Inferior , Idoso , Síndrome de Budd-Chiari/etiologia , Constrição Patológica/diagnóstico , Constrição Patológica/fisiopatologia , Veias Hepáticas , Humanos , Masculino , Doenças Vasculares Periféricas/diagnóstico , Doenças Vasculares Periféricas/fisiopatologia , Grau de Desobstrução Vascular/fisiologia
15.
J Biomech ; 16(9): 717-26, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6643543

RESUMO

The measurement of five gait parameters, namely, joint angular displacement of lower extremities, floor reaction forces, trajectory for a point of force application, temporal factor and distance factor has been performed with ease and high speed using mini-computer on-line real-time processing. Gait data of 211 patients with hip diseases was normalized, quantified and summarized by the principal component analysis. A 'gait evaluation plane' was formed according to the results obtained by the principal component analysis. The gait evaluation using the plane was compared with clinical conditions of patients, and it was evident that this system can evaluate the recovery of the gait by treatment.


Assuntos
Marcha , Articulação do Quadril/fisiologia , Artropatias/fisiopatologia , Fenômenos Biomecânicos , Humanos
16.
Br J Radiol ; 68(806): 116-20, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7735739

RESUMO

Dual contrast magnetic resonance imaging (DCMR) with combined use of a negative contrast medium, chondroitin sulfate iron colloid (CSIC), and a positive contrast medium, Gd-DTPA, was attempted in 20 cases of hepatocellular carcinoma. Spin echo T1 weighted and T2 weighted images (T1WI, T2WI), and T1 weighted images 15 min after intravenous injection of Gd-DTPA (0.1 mmol kg-1) were obtained. Within 1 week, these MR studies were repeated within 1 h of intravenous injection of CSIC (23.6 mumol Fe kg-1) under similar conditions. DCMR and the other five imaging techniques were visually evaluated and compared in terms of tumour detectability, tumour spread and qualification of tumours (depiction of inner structure). DCMR was significantly better than Gd-DTPA enhanced T1WI in tumour detectability, and better than Gd-DTPA enhanced T1WI or CSIC enhanced T1WI in depicting tumour spread. In the qualification of tumours, DCMR was significantly better than all the other five imaging techniques. None of the patients in this study showed adverse reactions or significant changes in biochemistry. DCMR is an imaging technique which is able to utilize the characteristics of these contrast agents collectively, and exhibits advantages in grasping the inner structure of tumours, especially in hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Sulfatos de Condroitina , Meios de Contraste , Ferro , Neoplasias Hepáticas/diagnóstico , Meglumina , Compostos Organometálicos , Ácido Pentético/análogos & derivados , Carcinoma Hepatocelular/patologia , Coloides , Combinação de Medicamentos , Feminino , Gadolínio DTPA , Humanos , Neoplasias Hepáticas/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade
17.
Br J Radiol ; 69(828): 1139-44, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9135470

RESUMO

To demonstrate the usefulness of iron colloid-enhanced MR images in differentiating hepatocellular carcinoma (HCC) from hyperplastic nodules (HN), microautoradiographs of chemically induced rat liver tumours were prepared 4 h after intravenous injection of chondroitin sulphate iron colloid (CSIC) labelled with 59Fe by the dipping technique. 20 Wistar rats were allocated into three groups: (1) a normal group, 10; (2) an HN group, 5; and (3) a liver cancer (LC) group, 5. In the I.C group, a diet containing 0.06% 3'-methydiaminobenzine tetrahydro-chloride (DAB) was administered for 3 months. In the HN group, a diet containing 0.025% acetylaminofluorene (AAF) was administered for 4 months. Non-labelled CSIC was intravenously injected into five rats in the normal group, and pseudomicroautoradiographs were prepared using the same technique (normal cold group). 50 sites for examination were randomly selected for each of the normal liver tissue, HN, well-differentiated HCC (HCC-W), and moderately to poorly-differentiated HCC (HCC-MP). The number of Kupffer cell-like macrophages and the photosensitized area ratio (PAR) per field of view were calculated. There was no significant difference in either the number of Kupffer cell-like macrophages or the PAR between HN and normal liver tissue. Although there was no significant difference in the number of these cells between groups HN and HCC-W, the PAR in group HCC-W was significantly lower than that in group HN (p = 0.045). In HCC-MP, both their number (p = 0.003) and the PAR (p = 1.18 x 10(-9)) were significantly lower than in group HCC-W. However, the PAR in HCC-MP was significantly higher than those in the normal cold group (p = 0.019). Iron colloid-enhanced MRI is useful for differentiating HCC from HN, and for diagnosing the degree of HCC differentiation.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Sulfatos de Condroitina , Coloides , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Animais , Diagnóstico Diferencial , Hiperplasia/diagnóstico , Ratos , Ratos Wistar
18.
Br J Radiol ; 69(827): 1000-4, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8958015

RESUMO

15 patients, aged 1-14 years, with sleep disordered breathing underwent turbo fast low angle shot MRI during drug-induced sleep. The site of obstruction within the pharynx was identified. Data from MRI were compared with fibroscopic findings. The degree of hypertrophy of the palatine tonsils as determined by MRI was also compared with that determined by visual inspection while awake. MRI was completed in all cases, whereas fibroscopy was completed in only six of the 10 cases examined. MRI findings agreed with those of fibroscopy in all the patients who underwent both investigations. On MRI, the pharynx was obstructed in 12 of the 15 cases examined (80%); the palatine tonsils were involved in all of these while both the palatine tonsils and nasopharynx were obstructed in three of the 12 cases. One of the 12 patients was graded as Grade I of Mackenzie's scale. One of the cases graded as Grade II showed no obstruction. In conclusion, fast MRI proved useful in identifying the site of pharyngeal obstruction in young patients with sleep disordered breathing.


Assuntos
Obstrução das Vias Respiratórias/diagnóstico , Imageamento por Ressonância Magnética , Faringe/patologia , Síndromes da Apneia do Sono/etiologia , Adolescente , Obstrução das Vias Respiratórias/etiologia , Criança , Pré-Escolar , Endoscopia , Feminino , Tecnologia de Fibra Óptica , Humanos , Hipertrofia/complicações , Hipertrofia/diagnóstico , Lactente , Masculino , Nasofaringe/patologia , Tonsila Palatina/patologia
19.
Br J Radiol ; 70(836): 791-7, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9486042

RESUMO

The optimum conditions for iron colloid enhanced fast spin echo (FSE) in the detection of hepatocellular carcinoma have not been clearly established as yet. MRI was performed on 14 patients with hepatocellular carcinoma (45 nodules) before and after administration of chondroitin sulphate iron colloid (CSIC). One type of conventional spin echo (CSE) (TR/TE = 1800/80) was then quantitatively and qualitatively compared with three types of FSE (FSE 1800 (TR/effective TE/echo factor = 1800/90/7); FSE 7 (3500/90/7); and FSE 11 (3500/99/11)). The liver signal-to-noise ratio (SNR) was significantly decreased after CSIC administration in all sequences, while the tumour-to-liver contrast-to-noise ratio (CNR) was significantly increased. Although the decreased ratio of the liver SNR was smaller on the three FSE sequences compared with CSE, the increased ratio of the tumour-to-liver CNR was higher on the FSE sequences. The highest increase of the tumour-to-liver CNR was on the FSE 7 sequence. The number of detectable tumours, both before and after the administration of CSIC, was largest on FSE 7. In conclusion, FSE with longer TR and TE, and decreased echo factor, was especially useful for CSIC enhanced liver MRI.


Assuntos
Carcinoma Hepatocelular/diagnóstico , Sulfatos de Condroitina , Meios de Contraste , Ferro , Neoplasias Hepáticas/diagnóstico , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Coloides , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
20.
Br J Radiol ; 69(822): 515-21, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8757653

RESUMO

The livers of normal rabbits were subjected to microwave tissue coagulation (MTC), and comparison was made of the subsequent time-course changes in tissue observed on MRI, CT and histopathological examination. 16 rabbits were used. MTC was performed with a 21 gauge needle electrode inserted into the liver at laparotomy. 1-2 h after thermal coagulation, a region with slightly lower attenuation than that of surrounding normal liver parenchyma was observed on CT, and no enhancement was detected. With MRI, change from high signal intensity to iso-signal intensity from the inner zone to the margin was found on T1 weighted images (T1WI), and heterogeneous high signal intensity was observed on T2 weighted images (T2WI). On Gd-DTPA enhanced MRI, no enhancement occurred. 1-4 weeks after coagulation, the cellular structure at the site of coagulation was lost on histological examination, and the tissue became necrotic. On CT, homogeneous water density was observed, and no enhancement was detected. With MRI, regions of iso- or slightly low signal intensity were observed on T1WI, and regions of heterogeneous high to low signal intensity were seen on T2WI. After 1 week, a granulation layer consisting mainly of fibrous tissue developed, and a ring-shaped enhancement was observed in the low signal intensity region on T1WI and in the high signal intensity region on T2WI. The ring-shaped enhancement was also noted on CT. MRI appears to be useful for observation of time-course changes following MTC therapy because of its sensitivity in the detection of tissue changes.


Assuntos
Eletrocoagulação , Fígado/efeitos da radiação , Micro-Ondas/uso terapêutico , Lesões Experimentais por Radiação/diagnóstico , Animais , Eletrodos , Cinética , Fígado/patologia , Fígado/cirurgia , Imageamento por Ressonância Magnética , Masculino , Coelhos , Lesões Experimentais por Radiação/diagnóstico por imagem , Lesões Experimentais por Radiação/patologia , Tomografia Computadorizada por Raios X
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