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1.
Sci Total Environ ; 926: 172081, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38554961

RESUMO

Mature compost can promote the transformation of organic matter (OM) and reduce the emission of polluting gases during composting, which provides a viable approach to reduce the environmental impacts of biodegradable plastics (BPs). This study investigated the impact of mature compost on polybutylene adipate terephthalate (PBAT) degradation, greenhouse gas (GHG) emission, and microbial community structure during composting under two treatments with mature compost (MC) and without (CK). Under MC, visible plastic rupture was advanced from day 14 to day 10, and a more pronounced rupture was observed at the end of composting. Compared with CK, the degradation rate of PBAT in MC was increased by 4.44 % during 21 days of composting. Thermobifida, Ureibacillus, and Bacillus, as indicator species under MC treatment, played an important role in PBAT decomposition. Mature compost reduced the total global warming potential (GWP) by 25.91 % via inhibiting the activity of bacteria related to the production of CH4 and N2O. Functional Annotation of Prokaryotic Taxa (FAPROTAX) further revealed that mature compost addition increased relative abundance of bacteria related to multiple carbon (C) cycle functions such as methylotrophy, hydrocarbon degradation and cellulolysis, inhibited nitrite denitrification and denitrification, thus alleviating the emission of GHGs. Overall, mature compost, as an effective additive, exhibits great potential to simultaneously mitigate BP and GHG secondary pollution in co-composting of food waste and PBAT.


Assuntos
Plásticos Biodegradáveis , Compostagem , Gases de Efeito Estufa , Eliminação de Resíduos , Gases de Efeito Estufa/análise , Perda e Desperdício de Alimentos , Alimentos , Solo/química , Metano/análise , Esterco
2.
Front Neurol ; 15: 1364108, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38481940

RESUMO

Objectives: To investigate the risk factors of pulmonary infection in patients with severe myelitis and construct a prediction model. Methods: The clinical data of 177 patients with severe myelitis at admission from the First Affiliated Hospital of Zhengzhou University from January 2020 to December 2022 were retrospectively analyzed. The predicting factors associated with pulmonary infection were screened by multivariate logistic regression analysis, and the nomogram model was constructed, and the predictive efficiency of the model was evaluated, which was verified by calibration curve, Hosmer-Lemeshow goodness-of-fit test and decision curve analysis. Results: Of the 177 patients with severe myelitis, 38 (21.5%) had pulmonary infection. Multivariate logistic regression analysis showed that neutrophil percentage to albumin ratio (NPAR) (OR = 6.865, 95%CI:1.746-26.993, p = 0.006) and high cervical cord lesion (OR = 2.788, 95%CI:1.229-6.323, p = 0.014) were independent risk factors for pulmonary infection, and the combined nomogram could easily predict the occurrence of pulmonary infection, with a C-index of 0.766 (95% CI: 0.678-0.854). The calibration curve, Hosmer-Lemeshow goodness-of-fit test (χ2 = 9.539, p = 0.299) and decision curve analysis showed that the model had good consistency and clinical applicability. Conclusion: The nomogram model constructed based on NPAR combined with high cervical cord lesion at admission has good clinical application value in predicting pulmonary infection in patients with severe myelitis, which is conducive to clinicians' evaluation of patients.

3.
J Biochem Mol Toxicol ; 36(2): e22957, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34796584

RESUMO

The hypothalamic paraventricular nucleus (PVN) is a specific center in the brain that regulates gastric mucosal injury following gastric ischemia-reperfusion (GI-R) injury. This study aimed to investigate whether autophagy-lysosome dysfunction in the PVN tissues of GI-R rats is involved in the gastric injury, and the underlying molecular mechanisms. The rat model of GI-R was established by clamping the celiac artery for 30 min and reperfusion for different hours (1, 3, and 6 h). The gastric injury was evaluated by hematoxylin and eosin staining of the stomach and the gastric mucosal index. The autophagy-lysosome dysfunction in the PVN was evaluated by the protein levels of LC3 II and Beclin-1 (markers for autophagosome activity) and the activity of acid phosphatase (a representative lysosomal enzyme). Immunohistochemical staining of ionized calcium-binding adaptor molecule 1 in the PVN was performed to evaluate microglial activation. Reactive oxygen species (ROS) content and phosphorylated γ-aminobutyric acid B receptor (p-GABAB R) expression in the PVN were also examined. The results revealed that, in GI-R rats, the shorter the reperfusion duration, the more severe the gastric mucosal damage. The autophagy-lysosome dysfunction exhibited by GI-R rats further enhanced microglial activation, ROS production, p-GABAB R expression, and gastric injury. In addition, activating microglial cells increased ROS production, p-GABAB R expression, and gastric injury in GI-R rats, while inhibiting microglial activation resulted in the opposite results. Taken together, autophagy-lysosome dysfunction induced by GI-R aggravated the gastric injury by inducing microglia activation.


Assuntos
Autofagia , Mucosa Gástrica/metabolismo , Lisossomos/metabolismo , Microglia/metabolismo , Núcleo Hipotalâmico Paraventricular/metabolismo , Traumatismo por Reperfusão/metabolismo , Gastropatias/metabolismo , Animais , Mucosa Gástrica/patologia , Lisossomos/patologia , Masculino , Microglia/patologia , Núcleo Hipotalâmico Paraventricular/patologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/patologia , Gastropatias/patologia
4.
J Immunol ; 202(3): 747-759, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30598514

RESUMO

G protein-coupled receptor 120 (GPR120) has been shown to negatively regulate inflammation and apoptosis, but its role in cerebral ischemic injury remains unclear. Using an in vivo model of middle cerebral artery occlusion (MCAO) and an in vitro model of oxygen-glucose deprivation (OGD), we investigated the potential role and molecular mechanisms of GPR120 in focal cerebral ischemic injury. Increased GPR120 expression was observed in microglia and neurons following MCAO-induced ischemia in wild type C57BL/6 mice. Treatment with docosahexaenoic acid (DHA) inhibited OGD-induced inflammatory response in primary microglia and murine microglial BV2 cells, whereas silencing of GPR120 strongly exacerbated the inflammation induced by OGD and abolished the anti-inflammatory effects of DHA. Mechanistically, DHA inhibited OGD-induced inflammation through GPR120 interacting with ß-arrestin2. In addition to its anti-inflammatory function, GPR120 also played a role in apoptosis as its knockdown impaired the antiapoptotic effect of DHA in OGD-induced rat pheochromocytoma (PC12) cells. Finally, using MCAO mouse model, we demonstrated that GPR120 activation protected against focal cerebral ischemic injury by preventing inflammation and apoptosis. Our study indicated that pharmacological targeting of GPR120 may provide a novel approach for the treatment of patients with ischemic stroke.


Assuntos
Apoptose , Isquemia Encefálica/prevenção & controle , Inflamação/prevenção & controle , Receptores Acoplados a Proteínas G/metabolismo , Ativação Transcricional , Animais , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/farmacologia , Inativação Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Células PC12 , Ratos , Receptores Acoplados a Proteínas G/genética , Acidente Vascular Cerebral/prevenção & controle
5.
J Neuroinflammation ; 15(1): 243, 2018 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-30157869

RESUMO

BACKGROUND: In Parkinson's disease (PD), loss of striatal dopaminergic (DA) terminals and degeneration of DA neurons in the substantia nigra (SN) are associated with inflammation. Nucleotide-binding oligomerization domain-containing protein (NOD)2, one of the first discovered NOD-like receptors, plays an important role in inflammation. However, the role of NOD2 has not been elucidated in PD. METHODS: NOD2 mRNA and protein expression in the SN and the striatum of C57BL/6 mice treated with 6-hydroxydopamine (6-OHDA) was measured. We next investigated the potential contribution of the NOD2-dependent pathway to 6-OHDA-induced DA degeneration using NOD2-deficient (NOD2-/-) mice. Assays examining DA degeneration and inflammation include HPLC, Western blot, immunohistochemistry, TUNEL staining, and cytometric bead array. To further explore a possible link between NADPH oxidase 2 (NOX2) and NOD2 signaling in PD, microglia were transfected with shRNA specific to NOX2 in vitro and apocynin were given to mice subjected to 6-OHDA and muramyl dipeptide (MDP) striatal injection. RESULTS: The expression of NOD2 was upregulated in an experimental PD model induced by the neurotoxin 6-OHDA. NOD2 deficiency resulted in a protective effect against 6-OHDA-induced DA degeneration and neuronal death, which was associated with the attenuated inflammatory response. Moreover, silencing of NOX2 in microglia suppressed the expression of NOD2 and the inflammatory response induced by 6-OHDA and attenuated the toxicity of conditioned medium from 6-OHDA or MDP-stimulated microglia to neuronal cells. Furthermore, apocynin treatment inhibited NOD2 upregulation and DA degeneration in the SN of WT mice induced by 6-OHDA and MDP. CONCLUSION: This study provides the direct evidence that NOD2 is related to 6-OHDA-induced DA degeneration through NOX2-mediated oxidative stress, indicating NOD2 is a novel innate immune signaling molecule participating in PD inflammatory response.


Assuntos
Dopamina/metabolismo , Regulação da Expressão Gênica/genética , NADPH Oxidase 2/metabolismo , Proteína Adaptadora de Sinalização NOD2/metabolismo , Oxidopamina , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/complicações , Acetofenonas/farmacologia , Acetofenonas/uso terapêutico , Animais , Apomorfina/farmacologia , Linhagem Celular Transformada , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Modelos Animais de Doenças , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Degeneração Neural/etiologia , Degeneração Neural/fisiopatologia , Proteína Adaptadora de Sinalização NOD2/genética , Doença de Parkinson Secundária/genética , Doença de Parkinson Secundária/metabolismo , Espécies Reativas de Oxigênio/metabolismo
6.
Eur J Pharmacol ; 815: 98-108, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28844872

RESUMO

Losartan, an angiotensin (Ang) II type 1 receptor blocker (ARB), has been revealed to protect against cerebral ischemia/reperfusion (I/R) injury. However, the mechanism by which losartan protect brain ischemia injury is still obscure. In this study, we investigated whether losartan protected against cerebral I/R injury by reducing apoptosis and the possible signaling pathways. Wistar rats were pretreated for 14 days with 5mg/kg losartan, and then subjected to middle cerebral artery occlusion (MCAO) for 2h followed by reperfusion. Meanwhile, PC12 cells pretreated with losartan were exposed to oxygen-glucose deprivation-reoxygenation (OGD/R), an in vitro model of cerebral ischemia. Our results showed that administration of losartan significantly inhibited the apoptosis by decreasing the number of apoptotic cells, decreasing the protein level of cleaved caspase-3, cytochrom C and Bax, and increasing the level of Bcl-2 both in vivo and in vitro. Moreover, losartan treatment markedly enhanced the phosphorylation of Akt and blockade of PI3K activity by wortmannin dramatically inhibited Akt phosphorylation and attenuated the anti-apoptotic effect of losartan. Furthermore, pretreatment with losartan significantly increased the protein level of ß-arrestin1 and silence of ß-arrestin1 by siRNA partly attenuated losartan-induced anti-apoptotic effect and the phosphorylation of Akt. These results suggested that ß-arrestin1 modulated the activation of Akt in losartan-induced anti-apoptotic effect in cerebral I/R. Our data would provide a new molecular basis for further understanding of protective effect of losartan in cerebral I/R injury and may provide benefits of using losartan in the treatment of cerebrovascular disease.


Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/complicações , Losartan/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/tratamento farmacológico , beta-Arrestina 1/metabolismo , Animais , Citoproteção/efeitos dos fármacos , Losartan/uso terapêutico , Masculino , Células PC12 , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Wistar , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia
7.
Neurochem Res ; 42(4): 1141-1150, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28005221

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative disorder and characterized by motor system disorders resulting in loss of dopaminergic (DA) neurons. CXC195, a novel tetramethylpyrazine derivative, has been shown strongest neuroprotective effects due to its anti-apoptotic activity. However, whether CXC195 protects against DA neuronal damage in PD and the mechanisms underlying its beneficial effects are unknown. The purpose of our study was to investigate the potential neuroprotective role of CXC195 and to elucidate its mechanism of action against 6-hydroxydopamine (6-OHDA)-induced mouse model of PD. CXC195 administration improved DA neurodegeneration in PD mice induced by 6-OHDA. Our further findings confirmed treatment of CXC195 at the dose of 10 mg/kg significantly inhibited the apoptosis by decreasing the level of cleaved caspase-3 and Bax, and increasing the level of Bcl-2 in 6-OHDA-lesioned mice. Meanwhile, 6-OHDA also decreased the amount of phosphorylated Akt while increased GSK-3ß activity (the amount of phosphorylated GSK-3ß at Ser9 was decreased) which was prevented by CXC195. Wortmannin, a specific PI3K inhibitor, dramatically abolished the changes induced by CXC195. Our study firstly demonstrated that CXC195 protected against DA neurodegeneration in 6-OHDA-induced PD model by its anti-apoptotic properties and PI3K/Akt/GSK3ß signaling pathway was involved in it.


Assuntos
Neurônios Dopaminérgicos/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Transtornos Parkinsonianos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Piperazinas/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazinas/uso terapêutico , Animais , Apoptose , Neurônios Dopaminérgicos/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fármacos Neuroprotetores/química , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Oxidopamina/toxicidade , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/tratamento farmacológico , Piperazinas/química , Piperazinas/farmacologia , Pirazinas/química , Pirazinas/farmacologia , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
8.
Acta Neuropathol ; 125(3): 439-57, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23315026

RESUMO

X-linked Myopathy with Excessive Autophagy (XMEA) is a childhood onset disease characterized by progressive vacuolation and atrophy of skeletal muscle. We show that XMEA is caused by hypomorphic alleles of the VMA21 gene, that VMA21 is the diverged human ortholog of the yeast Vma21p protein, and that like Vma21p, VMA21 is an essential assembly chaperone of the vacuolar ATPase (V-ATPase), the principal mammalian proton pump complex. Decreased VMA21 raises lysosomal pH which reduces lysosomal degradative ability and blocks autophagy. This reduces cellular free amino acids which leads to downregulation of the mTORC1 pathway, and consequent increased macroautophagy resulting in proliferation of large and ineffective autolysosomes that engulf sections of cytoplasm, merge, and vacuolate the cell. Our results uncover a novel mechanism of disease, namely macroautophagic overcompensation leading to cell vacuolation and tissue atrophy.


Assuntos
Adenosina Trifosfatases/metabolismo , Autofagia/genética , Doenças por Armazenamento dos Lisossomos/genética , Doenças por Armazenamento dos Lisossomos/prevenção & controle , Doenças Musculares/genética , Doenças Musculares/prevenção & controle , ATPases Vacuolares Próton-Translocadoras/deficiência , ATPases Vacuolares Próton-Translocadoras/genética , Animais , Células Cultivadas , Humanos , Concentração de Íons de Hidrogênio , Leucina/metabolismo , Doenças por Armazenamento dos Lisossomos/patologia , Lisossomos/genética , Lisossomos/metabolismo , Masculino , Camundongos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Doenças Musculares/patologia , Mutação/genética , Interferência de RNA/fisiologia , RNA Mensageiro/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Frações Subcelulares/metabolismo , Frações Subcelulares/patologia , Fatores de Tempo , Vacúolos/metabolismo
9.
Cell ; 137(2): 235-46, 2009 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-19379691

RESUMO

X-linked myopathy with excessive autophagy (XMEA) is a childhood-onset disease characterized by progressive vacuolation and atrophy of skeletal muscle. We show that XMEA is caused by hypomorphic alleles of the VMA21 gene, that VMA21 is the diverged human ortholog of the yeast Vma21p protein, and that like Vma21p it is an essential assembly chaperone of the V-ATPase, the principal mammalian proton pump complex. Decreased VMA21 raises lysosomal pH, which reduces lysosomal degradative ability and blocks autophagy. This reduces cellular free amino acids, which upregulates the mTOR pathway and mTOR-dependent macroautophagy, resulting in proliferation of large and ineffective autolysosomes that engulf sections of cytoplasm, merge together, and vacuolate the cell. Our results uncover macroautophagic overcompensation leading to cell vacuolation and tissue atrophy as a mechanism of disease.


Assuntos
Genes Ligados ao Cromossomo X , Doenças Musculares/genética , ATPases Vacuolares Próton-Translocadoras/metabolismo , Autofagia , Humanos , Lisossomos/metabolismo , Proteínas de Membrana/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , ATPases Vacuolares Próton-Translocadoras/genética
10.
Leuk Res ; 33(1): 60-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18706692

RESUMO

Presence of TP53 mutations has been associated with poor prognosis in diffuse large B-cell lymphoma (DLBCL), although this has remained controversial. The TP53 codon 72 polymorphism has shown negative impact on cancer survival, but this has not been analyzed in DLBCL. Furthermore, the MDM2 SNP309 has been associated with earlier age of onset in DLBCL. Here, we investigated the clinical impact of TP53 mutations, MDM2 SNP309 and TP53 codon 72 polymorphisms on survival in DLBCL of germinal center (GC) and non-GC subtypes. Thirteen of the 102 (12.7%) patients displayed TP53 mutations. Overall, TP53 mutations had a significant effect on lymphoma-specific survival (LSS, P=0.009) and progression-free survival (PFS, P=0.028). In particular, inferior survival was observed in TP53-mutated DLBCLs of GC subtype (LSS, P=0.002 and PFS, P=0.006). Neither MDM2 SNP309 nor the TP53 codon 72 polymorphism had an impact on age of onset or survival. Altogether, our data suggests that TP53 mutations are associated with poor outcome in GC-DLBCL patients.


Assuntos
Linfoma de Células B/genética , Linfoma não Hodgkin/genética , Mutação , Proteína Supressora de Tumor p53/genética , Humanos , Análise de Sobrevida
11.
J Child Neurol ; 23(2): 240-2, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18263761

RESUMO

Lafora epilepsy is characterized by starch formation in brain and skin and is diagnosed by skin biopsy or mutation detection. It has variable ages of onset (6-19 years) and death (18-32 years) even with the same mutation, likely due to extramutational factors. The authors identified 14 Lafora epilepsy patients in the genetic isolate of tribal Oman. The authors show that in this homogeneous environment and gene pool, the same mutation, EPM2B-c.468-469delAG, results in highly uniform ages of onset (14 years) and death (21 years). Biopsy, on the other hand, was not homogeneous (positive in 4/5 patients) and is, therefore, less sensitive than mutation testing.


Assuntos
Proteínas de Transporte/genética , Doença de Lafora/genética , Grupos Populacionais/genética , Adolescente , Adulto , Idade de Início , Proteínas de Transporte/metabolismo , Consanguinidade , Análise Mutacional de DNA , Morte , Humanos , Doença de Lafora/etnologia , Doença de Lafora/mortalidade , Doença de Lafora/fisiopatologia , Omã , Pele/metabolismo , Ubiquitina-Proteína Ligases
12.
J Neuropathol Exp Neurol ; 66(10): 944-54, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17917588

RESUMO

We investigated genetic heterogeneity of astrocytic gliomas using p53 gene mutations as a marker. Different parts of morphologically heterogeneous astrocytic gliomas were microdissected, and direct DNA sequencing of p53 gene exons 5 through 8 was performed. Thirty-five glioma samples and tumor-adjacent normal-appearing brain tissue from 11 patients were analyzed. Sixteen different p53 gene mutations were found in 7 patients. We found that some tumors were devoid of p53 gene mutations, whereas other tumors carried 1 or often several (up to 3) different mutations. The mutations were present in grade II, III, and IV astrocytic glioma areas. Both severe functionally dead mutants and mutants with remaining transcriptional activity could be observed in the same tumor. We observed that morphologically different parts of a glioma could carry different or similar mutations in the p53 gene and could be either associated or not associated with the locus of heterozygosity at the mutant site. Coexistence of p53 gene mutations and the locus of heterozygosity was common, at least in astrocytomas grade III and in glioblastomas, and also occurred in astrocytoma grade II areas. These results support the notion that intratumoral heterogeneity in brain tumors originates from different molecular defects. Our results are of importance for a further understanding of the molecular mechanisms behind failure to treat glioma patients.


Assuntos
Astrocitoma/genética , Neoplasias Encefálicas/genética , Genes p53/genética , Adulto , Idoso , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Primers do DNA , DNA de Neoplasias/genética , Feminino , Frequência do Gene , Genes p53/fisiologia , Humanos , Imuno-Histoquímica , Perda de Heterozigosidade , Masculino , Microdissecção , Pessoa de Meia-Idade , Mutação/genética , Mutação/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Acta Neuropathol ; 113(2): 129-36, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17031656

RESUMO

Oligoastrocytomas are glial tumours consisting of a mixture of neoplastic astrocytic and oligodendroglial cells. Genetic alterations of oligoastrocytomas include loss of heterozygosity of chromosomes 1p and/or 19q (LOH 1p/19q), typically occurring in oligodendrogliomas, and mutations of TP53, frequently occurring in astrocytomas. To investigate whether these neoplastic cell types in oligoastrocytomas have different genetic profiles, we examined the two different components of oligoastrocytomas in comparison with the histological diagnosis of the specific tumour area for LOH 1p/19q and TP53 mutations by using microdissection technique. We found a variety of lost markers for 1p and 19q, and the presence of two different TP53 mutations in the tumour samples. In the majority of cases (9/11), the oligodendroglial and astrocytic components of an individual oligoastrocytoma displayed the same genotype. We present two cases of biphasic oligoastrocytomas with aberrant findings, suggesting the coexistence of genetically and morphologically distinct tumour cell clones in these tumours. In one case, the oligodendroglial part of the tumour showed LOH19q, whereas the astrocytic part showed TP53 mutation (codon 273). In another case, we found LOH 1p/19q in the oligodendroglial component, but two retained areas on chromosome 1p in the astrocytic component of the tumour. No evidence was found for the coexistence of tumour cells with the two genotypical changes within the same morphological region of one individual tumour. The two cases of biphasic oligoastrocytomas in our sample that display a different genotype in the astrocytic and oligodendroglial part of the tumour show that different components of an oligoastrocytoma may be derived from different cell clones during neoplastic transformation.


Assuntos
Astrocitoma/classificação , Astrocitoma/genética , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/genética , Oligodendroglioma/genética , Adulto , Idoso , Astrocitoma/diagnóstico , Cromossomos Humanos Par 1/genética , Feminino , Humanos , Masculino , Repetições de Microssatélites , Pessoa de Meia-Idade , Mutação , Oligodendroglioma/diagnóstico , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Proteína Supressora de Tumor p53/genética
14.
Med Oncol ; 23(1): 113-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16645236

RESUMO

Thirty tumors were collected from our archive of cervical adenocarcinomas. They were examined with respect to the content of oncogenic HPV and presence of mutations in the p53 gene exons 5 through 8. Furthermore, available clinical information on the cases was reviewed. For the detection of p53 gene and presence of oncogenic HPV, PCR followed by direct sequence analysis of the amplified DNA was employed. Seventeen tumors were identified as HPV-positive, comprising both HPV types 18 and 16. Six cases showed a p53 gene mutation, of which five were of the missence and one of the silent type. No statistical correlation between the occurrence of oncogenic HPV and presence of p53 gene mutation (p = 0.67) was recorded. Among the tumors with p53 gene mutation, three were HPV-positive and three were HPV-negative. The determination of p53 gene mutations was not related to clinical findings such as the stage of the tumor or presence of metastases of the lymph nodes. However, p53 gene mutations were somewhat more prevalent in low differentiated tumors (p < 0.02). The results indicate that oncogenic HPV and p53 gene mutations have independent carcinogenic roles in cervical adenocarcinomas.


Assuntos
Adenocarcinoma/etiologia , Genes p53 , Mutação , Papillomaviridae/isolamento & purificação , Neoplasias do Colo do Útero/etiologia , Adulto , Idoso , DNA Viral/análise , Feminino , Humanos , Pessoa de Meia-Idade
15.
Lab Invest ; 86(2): 202-11, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16402036

RESUMO

Molecular tools for tissue profiling, such as expression microarrays and real-time PCR, generally require collection of fresh frozen tissues as sources of high-quality RNA. The fragile nature of RNA prompted us to examine the effects of storage time and transport conditions with regard to RNA integrity and gene expression in nonfixed surgical human specimens. At surgery, fresh normal tonsil and colon tissue was cut into pieces and snap frozen. Additional fresh tissue pieces were (i) left at room temperature, (ii) kept on ice, (iii) in normal saline or (iv) in a commercial RNA-stabilizing buffer (RNAlater) and snap frozen after 0.5, 1, 3, 6 and 16 h. Structural RNA integrity was analysed by microchip electrophoresis. Surprisingly, RNA remained stable in both tissue types under all conditions tested for up to 6-16 h. Gene expression by real-time PCR of cfos, HIF1alpha, Bcl2, PCNA, TGFbeta1 and SMAD7 was analysed at different storage time points in tonsil tissue. Expression levels were essentially stable when samples were kept on ice, while marked regulation of single genes was observed during storage at room temperature, in normal saline and in RNAlater. Furthermore, we analysed selected tissue types from the local biobank representing 47 normal and malignant tissues transported on ice for up to 2-3 h before biobanking. RNA prepared from 45 of the 47 samples exhibited distinct ribosomal peaks indicating intact RNA. This study shows that RNA degradation is a minor problem during handling of fresh human tissue before biobanking. Our data indicate that nonfixed tissue specimens may be transported on ice for hours without any major influence on RNA quality and expression of the selected genes. However, further studies are warranted to clarify the impact of transport logistics on global gene expression.


Assuntos
RNA/metabolismo , Bancos de Tecidos , Sequência de Bases , Colo/metabolismo , Primers do DNA , DNA Complementar , Eletroforese em Microchip , Expressão Gênica , Humanos , Reação em Cadeia da Polimerase
16.
Biochem Biophys Res Commun ; 338(3): 1625-33, 2005 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-16288728

RESUMO

The aim of the present study was to investigate the effect of transforming growth factor-beta1 (TGF-beta1) on telomerase activity in a panel of human anaplastic thyroid carcinoma (ATC) cell lines. Addition of TGF-beta1 decreased the telomerase activity in HTh 74 and KTC-1 cells, while in C 643 and HTh 7 an increased activity was observed. The decreased telomerase activity appeared to be due to transcriptional repression of the hTERT promoter. Addition of a PI-3 kinase inhibitor (LY294002) abrogated the stimulatory effect of TGF-beta1 on the telomerase activity, indicating the possible involvement of hTERT activation via phosphorylation. Furthermore, the MEK-inhibitor U0126 had similar effects suggesting dual regulatory mechanisms. Interestingly, the cell lines differed genetically in that ATC cell lines responding with increased telomerase activity harbored a p53 mutation. In conclusion, TGF-beta1 exerts opposing effects on telomerase activity in ATC cell lines, possibly reflecting deregulation of TGF-beta1 signaling in a more malignant genotype.


Assuntos
Telomerase/metabolismo , Neoplasias da Glândula Tireoide/enzimologia , Fator de Crescimento Transformador beta/farmacologia , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Genótipo , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Mutação/genética , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Regiões Promotoras Genéticas/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-myc/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Telomerase/genética , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética , Fator de Crescimento Transformador beta1 , Proteína Supressora de Tumor p53/genética
17.
Med Sci Monit ; 10(9): BR331-8, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15328478

RESUMO

BACKGROUND: Early stage lung cancer is potentially curable by resection, but 30-50% of patients will relapse within five years after surgery. Therefore, the search for a predictive method capable of estimating the risk of recurrence in this population of patients is important. MATERIAL/METHODS: We analysed, on the one hand, the predictive powers for recurrent disease of the immunohistochemical expressions of p53 and the endothelial markers CD34 and CD105 in 53 NSCLC tumor samples, and, on the other hand, their correlations to serum VEGF and bFGF levels. Moreover, we sequenced the whole coding region of the p53 gene in 32 tumor samples for the presence of p53 mutations (exons 2-11) using a cDNA technique. RESULTS: The two endothelial markers correlated with each other. CD105 expression correlated with p53 expression, which was overexpressed in 49%. No other significant correlations between markers could be demonstrated. A significant correlation between p53 overexpression and recurrent disease was demonstrated (p=0.029). The mutational status of p53 correlated to p53 protein overexpression, but did not correlate with either of the immunohistochemical markers. The mutational status could not confirm an immunohistochemical correlation between p53 and recurrences (p=0.068). CONCLUSIONS: The present study demonstrates that p53 expression correlates with CD105 expression, and that p53 overexpression may indicate a lower recurrence risk in patients undergoing surgery for NSCLC stage I-IIIA, although future larger prospective studies are needed to fully elucidate this finding.


Assuntos
Proteínas Angiogênicas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Células Endoteliais/metabolismo , Neoplasias Pulmonares/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD , Antígenos CD34/genética , Antígenos CD34/metabolismo , Biomarcadores , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Endoglina , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Receptores de Superfície Celular , Recidiva , Fatores de Risco , Estatística como Assunto , Taxa de Sobrevida , Proteína Supressora de Tumor p53/genética , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
18.
Acta Derm Venereol ; 84(6): 439-44, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15844633

RESUMO

The arginine variant of the p53 codon 72 polymorphism as well as anogenital and epidermodysplasia verruciformis (EV) types of human papilloma virus (HPV) are suggested to confer increased risk for developing cutaneous squamous cell carcinoma (SCC). In this pilot study, we analysed the p53 codon 72 genotype distribution in 106 microdissected samples from normal and tumour tissues of 53 cases of cutaneous SCC and 96 controls from Sweden. Both normal and tumour samples from cases of SCC were screened for anogenital and EV HPV. The p53Arg allele was not associated with the development of cutaneous SCC. Anogenital HPV (44%) was more prevalent than EV HPV (12%). Data also indicate that anogenital HPV is more common in tumour samples, but HPV infection was not identified as a significant risk factor for developing SCC. The presence of anogenital HPV, but not EV HPV might be a risk factor for development of cutaneous SCC.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/virologia , Genes p53 , Papillomaviridae/genética , Infecções Tumorais por Vírus/genética , Estudos de Casos e Controles , Códon , Condiloma Acuminado/genética , Condiloma Acuminado/virologia , Epidermodisplasia Verruciforme/genética , Frequência do Gene , Predisposição Genética para Doença/genética , Genótipo , Humanos , Perda de Heterozigosidade , Projetos Piloto , Reação em Cadeia da Polimerase , Fatores de Risco , Suécia , Infecções Tumorais por Vírus/virologia
19.
J Urol ; 168(5): 2240-4, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12394767

RESUMO

PURPOSE: We characterized early metastatic progression of bladder carcinoma from the primary tumor, separated in the central part and invasive front, to the first lymphatic metastasis. MATERIALS AND METHODS: Included in this study were 8 patients undergoing sentinel lymph node detection for invasive bladder cancer, of whom 4 had metastasis in the sentinel lymph node and 4 were randomly chosen without metastases. After microdissection p53 genomic structure and immunohistochemical expression of p53, pRB, Ki67 and E-cadherin were analyzed. Microvessel density and apoptosis were also assessed. RESULTS: In 5 patients there were p53 gene mutations in the primary tumor, while 3 had the wild-type gene. The genotypes were identical in the central part and invasive front. All sentinel lymph node metastases harbored p53 mutations, in contrast to all nonmetastatic sentinel lymph nodes. Two patients had the same mutation as the primary tumor and 1 had an additional mutation. In a patient with a wild-type gene in each compartment of the primary tumor a mutation appeared in the corresponding sentinel lymph node metastasis. There was poor concordance of p53 mutation with protein status. The expression of p53, pRB, Ki67, E-cadherin, and the evaluation of apoptosis and angiogenesis showed in most cases only slight variations in tumor compartments and the sentinel lymph node. CONCLUSIONS: In this study invasive bladder carcinoma involved monoclonal proliferations with a mainly homogenous biomarker profile. The first metastases in sentinel lymph nodes had a similar molecular profile but in half of the cases signs of clonal evolution appeared.


Assuntos
Biomarcadores Tumorais/genética , Metástase Linfática/genética , Biópsia de Linfonodo Sentinela , Neoplasias da Bexiga Urinária/genética , Apoptose/genética , Caderinas/genética , Divisão Celular/genética , Análise Mutacional de DNA , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/fisiologia , Humanos , Antígeno Ki-67/genética , Linfonodos/patologia , Metástase Linfática/patologia , Invasividade Neoplásica , Estadiamento de Neoplasias , Proteína do Retinoblastoma/genética , Proteína Supressora de Tumor p53/genética , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/patologia
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