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1.
Accredit Qual Assur ; 26(3): 157-164, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34149200

RESUMO

The International Atomic Energy Agency (IAEA) implemented an innovative project for assisting neutron activation analysis laboratories in improving the validity of their results by feedback workshops for discussion of results from participation in interlaboratory comparisons rounds in 2010. The participants learned during these meetings to identify the most probable sources of errors in their analytical procedures and how to implement corrective actions to prevent reoccurrence. The outcome of successive rounds between 2010 and 2018 is discussed and experiences during the feedback workshops are given. The quantitative evaluation of the results shows an overall improvement in satisfactory performance. Moreover, there is a clear indication that improvements are consolidated in most laboratories but also stimulate laboratories to develop to a higher level of excellence. Regional differences in performance are also analysed.

2.
Am J Physiol Gastrointest Liver Physiol ; 315(5): G887-G895, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30160974

RESUMO

The expression of amino acid transporters in small intestine epithelia of human newborns has not been studied yet. It is further not known whether the maturation of imino acid (proline) transport is delayed as in the kidney proximal tubule. The possibility to obtain small intestinal tissue from patients undergoing surgery for jejunal or ileal atresia during their first days after birth was used to address these questions. As control, adult terminal ileum tissue was sampled during routine endoscopies. Gene expression of luminal imino and amino acid transporter SIT1 (SLC6A20) was approximately threefold lower in newborns versus adults. mRNA levels of all other luminal and basolateral amino acid transporters and accessory proteins tested were similar in newborn mucosa compared with adults. At the protein level, the major luminal neutral amino acid transporter B0AT1 (SLC6A19) and its accessory protein angiotensin-converting enzyme 2 were shown by immunofluorescence to be expressed similarly in newborns and in adults. SIT1 protein was not detectable in the small intestine of human newborns, in contrast to adults. The morphology of newborn intestinal mucosa proximal and distal to the obstruction was generally normal, but a decreased proliferation rate was visualized distally of the atresia by lower levels of the mitosis marker Ki-67. The mRNA level of the 13 tested amino acid transporters and accessory proteins was nonetheless similar, suggesting that the intestinal obstruction and interruption of amniotic fluid passage through the small intestinal lumen did not affect amino acid transporter expression. NEW & NOTEWORTHY System IMINO transporter SIT1 is not expressed in the small intestine of human newborns. This new finding resembles the situation in the proximal kidney tubule leading to iminoglycinuria. Lack of amniotic fluid passage in small intestinal atresia does not affect amino acid transporter expression distal to intestinal occlusion.


Assuntos
Intestino Delgado/metabolismo , Proteínas de Membrana Transportadoras/genética , Adulto , Idoso , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Recém-Nascido , Intestino Delgado/crescimento & desenvolvimento , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Pessoa de Meia-Idade
4.
Pathologe ; 38(5): 416-421, 2017 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-28752179

RESUMO

BACKGROUND: The number of autopsies has been steadily declining worldwide over the past decades. The reasons for this are diverse. Legislation regarding opposition and consent rules does not appear to have had a significant impact on the autopsy rates. Above all, structural causes and the attitude of the medical profession are the reasons for this decline. The main argument for a high autopsy rate is the identification of diagnostic errors; however, diagnostic discrepancies are relatively independent of the rate of autopsies performed. At the University Hospital (UniversitätsSpital) Zurich it could be shown in a study that from 1972-2002 the frequency of relevant diagnostic discrepancies (classes I and II) decreased from 30% to 7%. OBJECTIVE: The aim of this article is to present the necessity of a stable autopsy rate and to examine the situation of the autopsy in Switzerland. MATERIAL AND METHODS: For this purpose, the importance of autopsies in the fields of quality assurance of medical diagnostics, cancer statistics, medical research as well as further education of doctors in Switzerland is shown. Efforts are being made by the pathologists to counteract the declining autopsy rates. RESULTS AND DISCUSSION: Declining autopsy numbers have a significant influence on cancer statistics. The rate of newly discovered tumors in autopsies in Switzerland decreased from 42% in 1980 to 17% in 2010. Pediatric autopsies are an important tool for quality assurance of medical diagnostics in neonatology and pediatrics in Switzerland, but the rate of autopsies carried out is also declining. Postmortem magnetic resonance imaging (MRI) examinations (virtopsy) could increase the acceptance of the parents for an autopsy in the future. Autopsies make an important contribution in research and in documentation of therapy-associated side effects and they are an important component of further education of the upcoming medical generations.


Assuntos
Autopsia/estatística & dados numéricos , Atitude do Pessoal de Saúde , Autopsia/tendências , Diagnóstico Diferencial , Erros de Diagnóstico , Hospitais Universitários/estatística & dados numéricos , Humanos , Prevalência , Suíça
5.
Cytopathology ; 28(3): 184-191, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28217933

RESUMO

OBJECTIVE: The primary objective of this study was to describe the cytological findings of bowel and (penile) skin-lined neovaginas in patients with gender dysphoria (GD) and individuals with a congenital or acquired absence of a natural vagina. The secondary objective was to correlate the cytological findings with clinical characteristics such as oestrogen replacement therapy (ERT). METHODS: A retrospective review of an institutional pathology archive over a 15-year-period was performed to identify cytological samples of neovaginal vaults. The medical and surgical records of the patients identified (n=20) were evaluated. RESULTS: Well-preserved nucleated squamous cells were found in 70% (14/20) of patients. Neovaginal samples showing superficial, intermediate and parabasal cells plus Döderlein flora similar to normal cervical cytology were present in only 10% (2/20). Three samples (15%, 3/20) showed atypical squamous cells of undetermined significance (ASC-US) that were all negative for high-risk human papillomavirus (HR-HPV) types, whereas one case was positive for low-risk (LR) HPV. One patient (5%, 1/20) was diagnosed with an HR-HPV-positive high-grade squamous intraepithelial lesion (HSIL), and one patient (5%, 1/20) had an HR- and LR-HPV-positive low-grade squamous intraepithelial lesion (LSIL). The correlation between the presence of nucleated squamous cells and ERT was significant (P=.032). CONCLUSION: Cytological findings of the neovagina resemble normal cervical cytology with superficial, intermediate and parabasal cells as well as Döderlein bacilli in a minority of cases. Because precancerous lesions and invasive carcinoma may develop in the neovagina, patients with neovaginas should be subject to cancer screening programmes.


Assuntos
Vagina/patologia , Adulto , Idoso , Células Escamosas Atípicas do Colo do Útero/patologia , Células Escamosas Atípicas do Colo do Útero/virologia , Colo do Útero/patologia , Colo do Útero/virologia , Colposcopia , Citodiagnóstico/métodos , Detecção Precoce de Câncer , Feminino , Humanos , Pessoa de Meia-Idade , Papillomaviridae/patogenicidade , Infecções por Papillomavirus/complicações , Estudos Retrospectivos , Lesões Intraepiteliais Escamosas Cervicais/patologia , Lesões Intraepiteliais Escamosas Cervicais/virologia , Pessoas Transgênero , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Vagina/virologia , Adulto Jovem , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia
6.
Pathologe ; 37(2): 166-71, 2016 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-26942729

RESUMO

Nephroblastomas are the most commonly occurring renal neoplasms in childhood and are treated almost exclusively in clinical trials. An important factor for further therapeutic management is the pathological evaluation of the nephrectomy specimen. Tumor stage and risk group classification are the most crucial parameters. An independent assessment of the tumor by a reference pathology center is an essential standard procedure. Although many molecular genetic discoveries have been made in nephroblastomas over recent years, molecular parameters do not (yet) play a role in treatment stratification.


Assuntos
Neoplasias Renais/patologia , Neoplasias Renais/terapia , Tumor de Wilms/patologia , Tumor de Wilms/terapia , Criança , Ensaios Clínicos como Assunto , Fidelidade a Diretrizes , Humanos , Rim/patologia , Neoplasias Renais/genética , Estadiamento de Neoplasias , Nefrectomia , Medição de Risco , Tumor de Wilms/genética
7.
QJM ; 109(6): 417-8, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26740505
8.
Oncogene ; 35(16): 2020-30, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-26189795

RESUMO

Current treatment regimens for rhabdomyosarcoma (RMS), the most common pediatric soft tissue cancer, rely on conventional chemotherapy, and although they show clinical benefit, there is a significant risk of adverse side effects and secondary tumors later in life. Therefore, identifying and targeting sub-populations with higher tumorigenic potential and self-renewing capacity would offer improved patient management strategies. Hedgehog signaling has been linked to the development of embryonal RMS (ERMS) through mouse genetics and rare human syndromes. However, activating mutations in this pathway in sporadic RMS are rare and therefore the contribution of hedgehog signaling to oncogenesis remains unclear. Here, we show by genetic loss- and gain-of-function experiments and the use of clinically relevant small molecule modulators that hedgehog signaling is important for controlling self-renewal of a subpopulation of RMS cells in vitro and tumor initiation in vivo. In addition, hedgehog activity altered chemoresistance, motility and differentiation status. The core stem cell gene NANOG was determined to be important for ERMS self-renewal, possibly acting downstream of hedgehog signaling. Crucially, evaluating the presence of a subpopulation of tumor-propagating cells in patient biopsies identified by GLI1 and NANOG expression had prognostic significance. Hence, this work identifies novel functional aspects of hedgehog signaling in ERMS, redefines the rationale for its targeting as means to control ERMS self-renewal and underscores the importance of studying functional tumor heterogeneity in pediatric cancers.


Assuntos
Carcinogênese , Proteínas Hedgehog/metabolismo , Rabdomiossarcoma Embrionário/patologia , Transdução de Sinais , Humanos , Prognóstico , Rabdomiossarcoma Embrionário/metabolismo , Células Tumorais Cultivadas
9.
Br J Cancer ; 113(3): 411-3, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26171934

RESUMO

BACKGROUND: Many testicular germ cell cancers are curable despite metastatic disease, but about 10-15% of patients fail cisplatin-based first-line treatment. Immunotherapy is considered as additional treatment approach for these patients. Inhibition of the interaction between Programmed Death Receptor 1 (PD-1) and Programmed Death Receptor Ligand 1 (PD-L1) enhances T-cell responses in vitro and mediates clinical antitumour activity. We analysed the expression of PD-L1 in testicular germ cell tumours to evaluate its potential as target for immunotherapeutic strategies. METHODS: Immunohistochemistry was performed in 479 formalin-fixed paraffin-embedded specimens using a rabbit monoclonal antibody (E1L3N). The tissue microarray consisted of 208 pure seminomas, 121 non-seminomas, 20 intratubular germ cell neoplasia unclassified (IGCNU) and 20 specimens of non-neoplastic testicular tissue. RESULTS: Programmed Death Receptor Ligand-1 expression was found in 73% of all seminomas and in 64% of all non-seminomas. None of 20 IGCNU and none of 20 normal tissue specimens exhibited PD-L1 expression. PD-L1 positive stromal cells were only detected in seminomas, but not in non-seminomas. The anti PD-L1 antibody showed a pre-dominantly membranous staining pattern in testicular tumour cells, as well as expression in stromal cells. CONCLUSIONS: This frequent expression of PD-L1 in human testicular germ cell tumours suggests that patients with testicular germ cell tumours could profit from immunotherapeutic strategies using anti-PD1 and anti-PDL1 antibodies.


Assuntos
Antígeno B7-H1/metabolismo , Neoplasias Embrionárias de Células Germinativas/epidemiologia , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Testiculares/epidemiologia , Neoplasias Testiculares/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Embrionárias de Células Germinativas/patologia , Seminoma/epidemiologia , Seminoma/metabolismo , Seminoma/patologia , Neoplasias Testiculares/patologia , Testículo/metabolismo , Testículo/patologia , Análise Serial de Tecidos , Adulto Jovem
10.
Pathologe ; 35(3): 224-31, 2014 May.
Artigo em Alemão | MEDLINE | ID: mdl-24744185

RESUMO

Testicular germ cell tumors are generally rare but represent the most common solid neoplasms in young men. They are subdivided into seminomas and non-seminomatous germ cell tumors. Usually the diagnosis of a seminoma is straightforward due to the characteristic morphology, although problems in differential diagnosis can occur because of unusual histological growth patterns. This article describes the challenging differential diagnosis with respect to seminomas versus non-seminomatous germ cell tumors, sex cord stromal tumors, lymphomas and non-neoplastic conditions, such as scars and inflammatory changes. In addition, prognostic factors for seminomas are presented and discussed.


Assuntos
Seminoma/patologia , Neoplasias Testiculares/patologia , Coriocarcinoma/patologia , Diagnóstico Diferencial , Tumor do Seio Endodérmico/patologia , Humanos , Linfoma/patologia , Masculino , Neoplasias Embrionárias de Células Germinativas/patologia , Prognóstico , Tumor de Células de Sertoli/patologia , Tumores do Estroma Gonadal e dos Cordões Sexuais/patologia , Doenças Testiculares/patologia , Testículo/patologia
11.
Vet J ; 197(2): 468-73, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23583003

RESUMO

Hereditary copper-associated hepatitis in dogs resembles Wilson's disease, a copper storage disease in humans. Values for urinary copper excretion are well established in the diagnostic protocol of Wilson's disease, whereas in dogs these have not been evaluated. The objectives of this study were to characterize both basal and D-penicillamine induced urinary copper, zinc and iron excretion in dogs in relation to hepatic copper concentration. Beagles, Beagle-Bedlington terrier cross-breeds homozygous for the COMMD1 gene mutation that causes copper toxicosis, and Labrador retrievers with normal or increased hepatic copper concentrations were investigated. The hepatic copper phenotype was determined by histological evaluation of liver biopsies and measurement of the hepatic copper concentration by instrumental neutron activation analysis. Urinary excretion of copper, iron and zinc was measured via inductively coupled plasma optical emission spectrometry under basal conditions and after oral administration of a single dose (20mg/kg bodyweight) of the chelator D-penicillamine. There was a rapid increase in urinary excretion of copper and zinc, but not iron after D-penicillamine administration. This increase was not different between dogs with high or normal hepatic copper concentrations. D-penicillamine-induced urinary copper excretion and the copper/creatinine ratio did not correlate with hepatic copper concentrations in the dogs studied, although basal urinary copper/zinc ratios did correlate with hepatic copper concentrations in Labrador retrievers. The latter parameter may be useful in diagnostic and follow-up protocols for copper-associated hepatitis in Labrador retrievers.


Assuntos
Quelantes/uso terapêutico , Cobre/urina , Doenças do Cão/tratamento farmacológico , Ferro/urina , Hepatopatias/veterinária , Fígado/química , Penicilamina/uso terapêutico , Zinco/urina , Animais , Cobre/química , Cobre/metabolismo , Doenças do Cão/genética , Doenças do Cão/urina , Cães , Fígado/metabolismo , Hepatopatias/tratamento farmacológico , Hepatopatias/metabolismo , Hepatopatias/urina
12.
Pathologe ; 34(1): 70-3, 2013 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-22706883

RESUMO

We describe a case of a testicular primitive neuroectodermal tumor (PNET) with intratubular germ cell neoplasia of the adjacent testicular parenchyma. The occurrence of testicular PNET is rare because malignant transformation of testicular germ cell tumors into somatic malignancy is uncommon. Based on morphological, immunohistochemical and molecular pathological findings these tumors resemble central PNETs as they otherwise typically occur in children without rearrangement of the Ewing sarcoma breakpoint region (EWSR) gene on chromosome 22. This case also showed no evidence for a translocation.


Assuntos
Biomarcadores Tumorais/genética , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Neoplasias Embrionárias de Células Germinativas/genética , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Testiculares/genética , Neoplasias Testiculares/patologia , Adulto , Proteínas de Ligação a Calmodulina/genética , Carcinoma in Situ/genética , Carcinoma in Situ/patologia , Carcinoma in Situ/cirurgia , Cromossomos Humanos Par 21/genética , Cromossomos Humanos Par 22/genética , Rearranjo Gênico/genética , Humanos , Hibridização in Situ Fluorescente , Antígeno Ki-1/genética , Masculino , Neoplasias Embrionárias de Células Germinativas/cirurgia , Tumores Neuroectodérmicos Primitivos Periféricos/cirurgia , Fator 3 de Transcrição de Octâmero/genética , Orquiectomia , Proteína EWS de Ligação a RNA , Proteínas de Ligação a RNA/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Testiculares/cirurgia , Testículo/patologia , Translocação Genética/genética
13.
J Radioanal Nucl Chem ; 291(2): 569-572, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-26224914

RESUMO

The assumption that the shape of the epithermal neutron spectrum can be described, in any research reactor, by the 1/E1+α function is a fundamental starting point of the k0 standardization. This assumption may be questioned from a reactor physics viewpoint. The type of moderator, the existence of neutron reflectors, the additional production of (γ, n) neutrons and resonance capture by construction materials may be different for each reactor, with consequences for the shape of the neutron spectrum. This dependency may explain that various practitioners reported contradicting experiences with the use of Zr-Au flux monitors for the determination of the α-parameter. An objective view on the influence of the design of the reactor and irradiation facility on the shape of the neutron spectrum can be obtained by modeling. This has been applied in the Reactor Institute Delft for reactor configurations in which the irradiation facilities face the fuel elements with the presence of beryllium reflector elements. The Monte Carlo calculations indicate a distortion of the 1/E1+α relationship at the higher energy edge of the epithermal neutron spectrum. This distortion is attributed to the formation and thermalisation of both photoneutrons and (n, 2n) produced fast neutrons in the beryllium, and has a direct impact on the resonance activation of 95Zr, other than represented by the 1/E1+α function. The obtained relationship between neutron flux and neutron energy was also used for estimating the f-value and compared with the value obtained by the Delft Cr-Mo-Au flux monitor.

14.
Pathologe ; 30(6): 478-80, 2009 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-19784652

RESUMO

Sialolipoma is a relatively new and rare variant of lipoma of the salivary glands characterized by the combination of classical lipoma morphology with non-neoplastic ductulo-acinary salivary tissue components. Including the presented case, 27 sialolipomas, 14 of them localized in the parotid gland, have been published. We describe the clinical, radiological and pathomorphological characteristics of a parotid sialolipoma in a 43-year-old man.


Assuntos
Lipoma/diagnóstico , Lipoma/patologia , Neoplasias Parotídeas/diagnóstico , Neoplasias Parotídeas/patologia , Adulto , Diagnóstico Diferencial , Humanos , Lipoma/cirurgia , Imageamento por Ressonância Magnética , Masculino , Glândula Parótida/patologia , Glândula Parótida/cirurgia , Neoplasias Parotídeas/cirurgia
15.
J Vet Intern Med ; 23(5): 957-63, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19627473

RESUMO

BACKGROUND: Copper-associated chronic hepatitis (CACH) recently has been recognized in the Labrador Retriever as an inherited disorder with a late onset of clinical signs. No studies have investigated dietary management for the long-term treatment of this disease or for its potential in delaying the onset of clinical signs in subclinical cases. OBJECTIVES: To investigate the effects of a low-copper diet and zinc gluconate on hepatic copper concentrations in Labrador Retrievers with abnormal hepatic copper concentrations. ANIMALS: Twenty-four client-owned Labradors that were related to patients affected with CACH and that had been diagnosed with increased hepatic copper concentrations. METHODS: Hepatic copper concentrations were assessed before and after an average of 8 and 16 months of treatment. During this time, all dogs were fed exclusively a low-copper diet. In addition, dogs were assigned to 1 of 2 groups in a randomized double-blind manner to receive a supplement of zinc gluconate or placebo. RESULTS: Twenty-one dogs completed the study. Hepatic copper concentrations decreased in both groups at recheck 1 (n = 21; group 1, P < .001; group 2, P= .001) and at recheck 2 (n= 16; group 1, P= .03; group 2, P= .04). No difference in hepatic copper concentrations was found between the 2 groups before treatment (P= .65), at recheck 1 or at recheck 2 (P= .52-.79). CONCLUSIONS AND CLINICAL RELEVANCE: Feeding low-copper diets to Labradors is effective in decreasing hepatic copper concentrations. Adjunctive treatment with zinc does not appear to increase the copper-lowering effects of dietary management.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas/veterinária , Cobre/metabolismo , Doenças do Cão/dietoterapia , Doenças do Cão/metabolismo , Gluconatos/administração & dosagem , Hepatite Animal/induzido quimicamente , Animais , Biópsia/veterinária , Doença Hepática Crônica Induzida por Substâncias e Drogas/dietoterapia , Doença Hepática Crônica Induzida por Substâncias e Drogas/metabolismo , Cobre/administração & dosagem , Cães , Método Duplo-Cego , Feminino , Predisposição Genética para Doença , Gluconatos/farmacocinética , Hepatite Animal/dietoterapia , Histocitoquímica , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino
16.
Appl Radiat Isot ; 67(7-8 Suppl): S359-61, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19394243

RESUMO

A Monte Carlo calculation was carried out for boron neutron capture therapy (BNCT) of extra corporal liver phantom. The present paper describes the basis for a subsequent clinical application of the prompt gamma spectroscopy set-up aimed at in vivo monitoring of boron distribution. MCNP code was used first to validate the homogeneity in thermal neutron field in the liver phantom and simulate the gamma ray detection system (collimator and detector) in the treatment room. The gamma ray of 478 keV emitted by boron in small specific region can be detected and a mathematical formalism was used for the tomography image reconstruction.


Assuntos
Terapia por Captura de Nêutron de Boro/métodos , Boro/farmacocinética , Boro/uso terapêutico , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/secundário , Espectrometria gama/métodos , Terapia por Captura de Nêutron de Boro/estatística & dados numéricos , Nêutrons Rápidos/uso terapêutico , Humanos , Processamento de Imagem Assistida por Computador/métodos , Processamento de Imagem Assistida por Computador/estatística & dados numéricos , Técnicas In Vitro , Modelos Estatísticos , Método de Monte Carlo , Países Baixos , Imagens de Fantasmas/estatística & dados numéricos , Espectrometria gama/estatística & dados numéricos
18.
Appl Radiat Isot ; 66(12): 1964-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18639463

RESUMO

The Zr-Au set for monitoring the thermal and epithermal neutron fluence rate and the epithermal spectrum parameter alpha is not always practicable for routine application of INAA in well-thermalized facilities. An alternative set consisting of Cr, Au and Mo provides values for the thermal neutron fluence rate, f and alpha that are not significantly different from those found via the Zr-Au method and the Cd-covered Zr-method. The IRMM standard SMELS-II was analyzed using the (Au-Cr-Mo) monitor and a good agreement was obtained.


Assuntos
Análise de Ativação de Nêutrons/instrumentação , Termografia/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Análise de Ativação de Nêutrons/métodos , Doses de Radiação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Termografia/métodos
19.
Anim Genet ; 38(2): 168-70, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17355395

RESUMO

A deletion in the copper metabolism (Murr1) domain containing 1 (COMMD1) gene is associated with hepatic copper toxicosis in dogs, yet evidence of copper retention in COMMD1-depleted hepatic cells has not been shown. In a dog hepatic cell line, we analysed the copper metabolic functions after an 80% (mRNA and protein) COMMD1 reduction with COMMD1-targeting siRNAs. Exposure to 64Cu resulted in a significant increase in copper retention in COMMD1-depleted cells. COMMD1-depleted cells were almost three times more sensitive to high extracellular copper concentrations. Copper-mediated regulation of metallothionein gene expression was enhanced in COMMD1-depleted cells. Based on the increased copper accumulation and enhanced cellular copper responses upon COMMD1 reduction, we conclude that COMMD1 has a major regulatory function for intracellular copper levels in hepatic cells.


Assuntos
Proteínas de Transporte/metabolismo , Cobre/metabolismo , Regulação da Expressão Gênica/genética , Fígado/citologia , Interferência de RNA , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas de Transporte/genética , Linhagem Celular , Cães , Fígado/metabolismo , Metalotioneína/metabolismo , RNA Interferente Pequeno/genética
20.
J Vet Intern Med ; 20(4): 856-61, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16955809

RESUMO

This study summarizes the clinical and pathologic findings in 15 Labrador Retrievers with copper-associated chronic hepatitis (CACH). Our hypothesis was that this form of hepatitis is caused by a defect in hepatic copper metabolism, which most likely originates from a genetic defect. Affected Labradors consisted of 11 female and 4 male Labrador Retrievers. Eight family members of 2 of these patients were examined prospectively, as were 6 unrelated healthy Labrador Retrievers. All dogs were registered at the breed club. The average age at clinical presentation was 7 years (range, 2.5-10.5 years). All dogs were presented for anorexia, which was associated with vomiting in 8 patients. The diagnosis of CACH was based on histologic examination of liver biopsy specimens in all dogs, including semiquantitation of copper. A disproportionate increase in alanine aminotransferase (ALT) activity relative to alkaline phosphatase (ALP) activity, as well as the centrolobular localization of copper and the association of copper accumulation with hepatic lesions, suggested a primary copper storage disease rather than primary cholestatic liver disease causing copper accumulation. Mean hepatic copper concentration measured in related Labradors was 1,317 microg/g dry weight liver (range, 402-2,576 microg/g). Mean hepatic copper concentration of unrelated normal Labradors was 233 microg/g dry weight liver (range, 120-304 microg/g). Our findings support the hypothesis that a hereditary form of hepatitis occurs in Labrador retrievers and is caused by a defect in hepatic copper metabolism.


Assuntos
Cobre/metabolismo , Doenças do Cão/etiologia , Hepatite Crônica/veterinária , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Cobre/análise , Doenças do Cão/genética , Cães , Feminino , Predisposição Genética para Doença , Hepatite Crônica/tratamento farmacológico , Hepatite Crônica/genética , Fígado/química , Fígado/patologia , Masculino
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