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1.
Int J Mol Sci ; 23(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35887280

RESUMO

Diseases of the muscle tissue, particularly those disorders which result from the pathology of individual muscle cells, are often called myopathies. The diversity of the content of individual cells is of interest with regard to their role in both biochemical mechanisms and the structure of muscle tissue itself. These studies focus on the preliminary analysis of the differences that may occur between diseased tissues and tissues that have been recognised as a reference group. To do so, 13 samples of biopsied human muscle tissues were studied: 3 diagnosed as dystrophies, 6 as (non-dystrophic) myopathy and 4 regarded as references. From these sets of muscle biopsies, 135 completely measured muscle fibres were separated altogether, which were subjected to investigations using synchrotron radiation X-ray fluorescence (SR-XRF). Muscle fibres were analysed in terms of the composition of elements such as Br, Ca, Cl, Cr, Cu, Fe, K, Mn, P, S and Zn. The performed statistical tests indicate that all three groups (dystrophies-D; myopathies-M; references-R) show statistically significant differences in their elemental compositions, and the greatest impact, according to the multivariate discriminate analysis (MDA), comes from elements such as Ca, Cu, K, Cl and S.


Assuntos
Fibras Musculares Esqueléticas , Síncrotrons , Humanos , Radiografia , Espectrometria por Raios X , Raios X
2.
Postepy Hig Med Dosw (Online) ; 70(0): 1117-1123, 2016 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-27892895

RESUMO

INTRODUCTION: Prothymosin alpha (PTMA), a nuclear oncoprotein involved in cell cycle regulation, is used as a prognostic marker in many cancers. The histopathology of pituitary carcinomas and locally invasive adenomas is indistinguishable from that of benign tumors. A new marker is needed to differentiate these lesions. We evaluated PTMA in pituitary adenomas to determine its usefulness as a prognostic factor of tumor proliferation. MATERIAL/METHODS: We conducted a retrospective analysis of a group of 27 patients, including 15 females (56%) and 12 males (44%) with a mean age of 58.6±12 years, who underwent pituitary tumor surgery between 2003 and 2012. The Ki-67 and PTMA-nuclear (PTMA-n) and PTMA-cytoplasmic (PTMA-c) indices were determined by immunohistochemical staining. We studied histopathological features, clinical symptoms, and magnetic resonance imaging or computed tomography performed before surgery and one year following surgery to evaluate tumor size and progression. RESULTS: The expression of Ki-67 was revealed in 77.8% of adenomas, PTMA-n in 81.5% and PTMA-c in 92.6%. The mean value of the Ki-67 index was 1.8%, PTMA-n was 1.84%, and PTMA-c was 35.6%. There was a significant positive correlation between Ki-67 and PTMA-n (p=0.009). We did not find any correlation between Ki-67, PTMA-c, and tumor progression. PTMA-n was found to be correlated with tumor size (p=0.045) and was higher in the case of gonadotropinomas (p=0.026). CONCLUSIONS: The positive nuclear expression of Ki-67 and PTMA was observed in the majority of pituitary adenomas. Neither the expression of Ki-67 nor that of PTMA-c was related to tumor recurrence or local invasion.


Assuntos
Adenoma/metabolismo , Biomarcadores Tumorais/metabolismo , Antígeno Ki-67/genética , Neoplasias Hipofisárias/metabolismo , Securina/genética , Adenoma/genética , Adulto , Idoso , Progressão da Doença , Feminino , Humanos , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Hipófise/metabolismo , Neoplasias Hipofisárias/genética , Estudos Retrospectivos , Securina/metabolismo
3.
Przegl Lek ; 73(2): 53-8, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27197423

RESUMO

INTRODUCTION: The unpredictable biology of pituitary adenomas makes it a therapeutic challenge. Moreover ,histopathology of pituitary carcinomas and locally invasive adenomas are indistinguishable from benign tumors and a new marker which would enable to differentiate those lesions is vital. The aim of the study was to evaluate Ki-67 and PTTG (pituitary tumour--transforming gene) expression in pituitary adenomas and their applicationas markers of tumour aggressiveness. MATERIAL AND METHODS: A retrospective analysis of 55 patients: 32 females(58%) and 23 males (42%), mean age 50 ± 16 years who underwent pituitary tumor surgery between 2003-2012. Ki-67 and PTTG indices were determined by immunohistochemical staining. Magnetic resonance imaging or computed tomography was performed beforehand and one year after surgery to figure a potential tumour progression, tumour size and correlation to adjacent tissues. RESULTS: The expression of Ki-67and PTTG was revealed in cell nucleiin 88% and 85% of adenomas, respectively. The median Ki-67 and PTTG indices were 1.4 and 1.0, respectively(p = 0.006). In the group with macroadenoma as compared with the group with microadenoma, median Ki-67 index was higher (1.4% vs. 1.03%; p = 0.02). We did not find correlation between both Ki-67 and PTTG indices and tumour progression. Tumours with positive immunostaining towards FSH revealed lower Ki-67 and PTTG indices than the rest with a negative one (0.6% vs.1.84%, p = 0.0004 and 0.67% vs 1.23%,p = 0.047; respectively). However, PTTG index was higher in the group with acromegaly as compared to the group with clinically non-functioning pituitary adenoma (NFPA) (1.28% vs.0.35%; p = 0.02). CONCLUSIONS: Positive nuclear expression of Ki-67 and PTTG was observed in the majority of pituitary adenomas. Only higher Ki-67 expression was related to the tumour invasiveness found on MRI/CT. Tumour progressionwas not related to both Ki-67 and PTTG expression.


Assuntos
Adenoma/metabolismo , Antígeno Ki-67/metabolismo , Neoplasias Hipofisárias/metabolismo , Securina/metabolismo , Acromegalia/metabolismo , Adenoma/diagnóstico , Adenoma/genética , Adulto , Idoso , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Progressão da Doença , Feminino , Expressão Gênica , Humanos , Antígeno Ki-67/genética , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/diagnóstico , Neoplasias Hipofisárias/genética , Estudos Retrospectivos , Securina/genética
4.
Metallomics ; 7(11): 1522-31, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26440290

RESUMO

Human brain aging is considered to be the leading risk factor for a variety of neurodegenerative alterations. In particular, it is thought that the human substantia nigra might play a pivotal role in age-associated dopamine depletion which could be responsible for neuronal demise and subsequent emergence of different neurological alterations. A plethora of neurochemical redox- and non-redox-driven mechanisms is mainly associated with modifications in the elemental composition of both neuromelanin-pigmented neurons and extraneuronal spaces in the human substantia nigra pars compacta (SNpc). An age-associated variation in the content of Fe, Cu, Zn and Ca has recently received great interest in neurology, as these elements are implicated in different biochemical mechanisms underlying malicious neurodegenerative disorders, including Parkinson's and Alzheimer's diseases. Interestingly, to the best our knowledge, there is lack of a comprehensive study on age-associated variation in the elemental composition of the human SNpc. In that respect, the aim of the present study was to make a preliminary attempt to unravel some of the age-associated mechanisms responsible for the metabolism of some redox-active and redox-inactive elements in the elderly. To do so, substantia nigra tissue specimens, drawn from 37 individuals who deceased without any signs of neurodegeneration, were subjected to spectroscopic studies using synchrotron radiation based X-ray fluorescence. Both neuromelanin-pigmented neurons and extraneuronal areas were studied. It appears that in the neurons, Fe tends to decrease, whilst Cu, Zn and Ca were found to accumulate as an individual gets older.


Assuntos
Envelhecimento/fisiologia , Metais Pesados/análise , Substância Negra/química , Idoso , Idoso de 80 Anos ou mais , Feminino , Histocitoquímica , Humanos , Masculino , Pessoa de Meia-Idade , Imagem Molecular , Espectrometria por Raios X , Substância Negra/citologia , Substância Negra/fisiologia , Síncrotrons
5.
Neurochem Int ; 76: 12-22, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24994003

RESUMO

There is growing evidence that a variety of biochemical processes that underlie the most frequent neurodegenerative diseases may have much in common with those connected with natural aging. It was shown that they involve, among others, lipid peroxidation and/or generation of insoluble in water protein deposits (i.e. alpha-synuclein and/or beta amyloid). Therefore, it is likely that the analysis of changes in both lipid and protein composition may be interesting in the light of any potential pathologies occurring within the dopaminergic system during physiological aging. Thereby, this paper presents a methodology for the analysis of age-related changes in a lipid and protein composition within human subtantia nigra tissue by means of Fourier transform infrared microspectroscopy (FTIRM). Particularly, the changes in the lipid saturation, unsaturation as well as in the protein secondary structure were examined. The studies were carried out on samples from 35 individuals who died without any signs of neurologic dysfunctions. Our results show that the level of lipid saturation increases inside the subtantia nigra tissue with age, though the total content of lipid decreases with age of individuals. Moreover, the statistically significant decrease in the protein content within neuron bodies was observed. Interestingly, it is presented that the content of the anti-parallel beta sheets for neuron bodies decreases from seventh to eighth decades of life and subsequently markedly increases from eighth to ninth decades of life, whilst, as regards extraneuronal spaces, the opposite trends are reported i.e. increase from the seventh to eighth decades, and subsequent decrease in the ninth decade of life. These observations, though preliminary, shed the light on a putative contribution of various pathological lipid- and protein-related processes underlying senescence, suggesting a "biochemical link" between the aetiology of the most common neurodegenerative diseases and physiological aging.


Assuntos
Envelhecimento/metabolismo , Lipídeos/análise , Proteínas/análise , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Substância Negra/química , Humanos , Substância Negra/fisiologia
7.
Metallomics ; 5(11): 1547-53, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23945910

RESUMO

Despite the enormous advances in medicine, brain tumours are still among the lesser-known types of tumours and carry the worst prognoses. Transition metals are believed to play an essential role in carcinogenesis. The aim of this study was to determine differences in the average oxidation state and trends in the changes in the chemical environment of iron and zinc contained in healthy and neoplastic tissues of the human brain. For this purpose, X-ray Absorption Spectroscopy was used, which enables the study of disordered matter. The samples were taken intraoperatively and then immediately frozen to slow down chemical processes. Sixteen tumour samples with various malignancy grades were studied as well as one control sample. For each sample four to eight spectra were recorded, with a shift between them not greater than 0.2 eV. In all of the samples, iron occurred in compounds with both Fe(2+) and Fe(3+). However, the ratio of Fe(ii) to Fe(iii) content in the tissue visibly increased with the tumour malignancy grade. The change in the oxidation state of iron did not correlate with the hypoxia level of the tissues. Analysis of EXAFS spectra of zinc atoms showed that the chemical environment of zinc atoms differed with the tumour malignancy grade. Additionally, cryogenic conditions were found to produce positive results in studies of biological samples, whose form under such conditions is close to their native state, without preparation-caused artefacts.


Assuntos
Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patologia , Ferro/química , Zinco/química , Humanos , Hipóxia/metabolismo , Hipóxia/patologia , Técnicas In Vitro , Modelos Teóricos , Oxirredução , Espectroscopia por Absorção de Raios X
8.
Folia Neuropathol ; 47(3): 240-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19813143

RESUMO

The expression of protein RCAS1 (receptor-binding cancer antigen expressed on SiSo cells), possibly involved in the mechanisms of evasion of immune surveillance by tumours, has been studied in brain astrocytomas grade III and IV and in metastatic carcinomas to the brain by means of double immunofluorescence with antibodies against RCAS1 and respectively anti-GFAP (astroglia) or CD68 or CD74 (macrophages/microglia). Expression of RCAS1 has been reported in many types of carcinomas and in some normal cells, including bone marrow macrophages. Nakabayashi and coworkers recently reported expression of RCAS1 in gliomas. So far no attention has been paid to expression of RCAS1 in non-neoplastic cellular elements of tumours such as macrophages and to the expression of RCAS1 in metastatic carcinomas. We found expression of RCAS1 co-localizing with GFAP+ cells of gliomas and with CD68 and CD74 in large macrophages infiltrating metastatic and primary tumours and sometimes in cells which had morphological characteristics of microglia. Moreover, sometimes strong RCAS1 positivity has been found in metastatic carcinomas. Whether expression of RCAS1 in macrophages accompanying brain tumours is of any importance it is not possible to ascertain at present. However, when elucidating the possible role of RCAS1 in tumour biology, it seems to be necessary to include its presence not only in neoplastic cells.


Assuntos
Antígenos de Neoplasias/biossíntese , Neoplasias Encefálicas/metabolismo , Glioma/metabolismo , Macrófagos/metabolismo , Microglia/metabolismo , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/imunologia , Imunofluorescência , Glioma/imunologia , Humanos
9.
J Pediatr Endocrinol Metab ; 22(7): 653-60, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19774847

RESUMO

Patients with a PROP1 inactivating mutation present combined pituitary hormone deficiency (CPHD) and pituitary maldevelopment. A retrospective analysis of 31 CPHD patients with a PROP1 mutation revealed two individuals, aged 18 and 4.5 years, who had undergone subtotal surgery to remove pituitary tumors, 16.8 x 12 mm and 9 x 10 x 12 mm in size. Histological reassessment of tissue samples revealed epithelial cells, partially oxyphilic, forming gland-like microcystic structures, most of them filled with eosinophilic colloid. These structures were directly linked with fragments of the posterior lobe. Neither atypia nor any traces of proliferation activity (Ki-67 LI=0%) were noted. Immunohistochemistry showed the presence of all hormonal phenotypes of cells. These findings corresponded to the intermediate lobe of the pituitary gland. For this type of pathology we propose the term 'cystic hyperplasia of the intermediate pituitary lobe' and suggest PROP1 gene assessment in patients with CPHD in order to avoid unnecessary neurosurgical interventions.


Assuntos
Cistos/patologia , Proteínas de Homeodomínio/genética , Hipopituitarismo/patologia , Adeno-Hipófise Parte Intermédia/patologia , Adolescente , Adulto , Cistos/metabolismo , Cistos/cirurgia , Feminino , Humanos , Hiperplasia , Hipopituitarismo/genética , Hipopituitarismo/metabolismo , Hipopituitarismo/cirurgia , Imageamento por Ressonância Magnética , Masculino , Adeno-Hipófise Parte Intermédia/metabolismo , Adeno-Hipófise Parte Intermédia/cirurgia , Hormônios Hipofisários/metabolismo , Estudos Retrospectivos
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