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1.
J Ethnopharmacol ; 259: 112908, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32387231

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Miconia albicans (Melastomataceae), commonly known in Brazil as "canela-de-velho", is used in folk medicine for treating rheumatoid arthritis and reducing pain and inflammation. THE AIM OF THE CURRENT WORK WAS: to provide data on physicochemical characterization of the drug plant and dried extract from M. albicans leaves, as well as investigate the anti-inflammatory effect and antioxidant stress profile from the standardized dried extract of this species employing different model systems. MATERIALS AND METHODS: plant material (dried crushed leaves) was extracted by turboextraction using 50% ethanol (v/v). Different pharmacological techniques were performed to establish quality control parameters of the plant drug, and dried extract of M. albicans (DEMA) was chemically characterized by HPLC-PDA to selection of the chemical marker. Total phenolic and flavonoid contents were determined by the Folin-Ciocalteu and AlCl3 colorimetric methods, respectively. Antioxidant potential of the DEMA was investigated by employing different in vitro antioxidant assays, including DPPH and ABTS radical scavenging assays, ferric reducing antioxidant assay, NO scavenging assay, metal ion (Fe2+) chelating activity and antioxidant capacity by inhibition of lipid peroxidation (TBARS). Finally, anti-inflammatory activity of the DEMA was evaluated using two models of acute inflammation: carrageenan induced inflammation and mechanical hyperalgesia. RESULTS AND DISCUSSION: M. albicans leaves, after drying in forced air circulation chamber at ±40 °C for 48 h and crushing in knife mill, presented a moisture content below the maximum allowed for plant drugs (6.4%). The powder of M. albicans was classified as moderately coarse and total ash content was found to be 6.27%. Preliminary phytochemical screening of DEMA revealed the presence of flavonoids, tannins, saponins, leucoanthocyanins and steroids. DEMA had significant higher total phenolic (551.3 mg gallic acid equivalent/g of dried extract) and flavonoid contents (367.19 mg catechin equivalent/g of dried extract). Two major compounds (λ = 340 nm) were identified in DEMA by HPLC-PDA: the flavonoids rutin and quercetin. Rutin content, selected as chemical marker, was determined and found to be 1.16 mg/g dried extract (r = 0.9941). Regarding to antioxidant activity, our results revealed the DEMA exhibited good antioxidant activity on different models. M. albicans treatment also reduced the levels of TNF-α e IL-1ß and consequently inflammatory nociception and edema caused by carrageenan injection. Based on previous studies and our results, is possible to suggest a positive correlation between the flavonoids rutin and quercetin and the antioxidant and anti-inflammatory capacities. CONCLUSION: Together, these data suggest that M. albicans has the possibility of use in conditions such as arthritis or other joint pain, even needing other work to better consolidate this profile.


Assuntos
Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Interleucina-1beta/análise , Melastomataceae/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Fator de Necrose Tumoral alfa/análise , Animais , Edema/tratamento farmacológico , Flavonoides , Peroxidação de Lipídeos , Masculino , Camundongos , Fenóis , Extratos Vegetais/química , Folhas de Planta/química , Taninos
3.
Br J Dermatol ; 148(6): 1115-24, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12828737

RESUMO

BACKGROUND: Although the antiproliferative and proapoptotic effects of interferon (IFN)-alpha are widely recognized, its antitumour mechanisms are not completely known. Recent studies indicate that the derepressed expression of the catalytic subunit of telomerase, human telomerase reverse transcriptase (hTERT), and telomerase activity (TA) are involved in the process of human carcinogenesis. Only a few studies have investigated the effects of IFN-alpha on hTERT and TA, with controversial results. Objectives To study the hTERT mRNA expression, TA and apoptosis in human melanoma cells treated with IFN-alpha. METHODS: Five human melanoma cell lines (Me665/2/21, Me665/2/60, HT-144, SK-Mel-28 and SK-Mel-5) were cultured in standard conditions and treated with 20000 IU mL-1 of human recombinant IFN-alpha-2b. Apoptosis was evaluated as hypodiploid DNA content determined by flow cytometry, caspase-3/7 activity by enzymatic assay, and poly(adenosine diphosphate-ribose) polymerase cleavage by Western blot analysis. IFN-alpha receptor (IFNA-R) and hTERT mRNA expression levels were evaluated by semiquantitative reverse transcription-polymerase chain reaction. TA was evaluated by a polymerase chain reaction-based telomerase repeat amplification protocol assay. RESULTS: Besides a variable degree of cell proliferation inhibition in all cell lines tested, we found different responses, ranging from no significant effects in SK-Mel-28 cells, to a high degree of apoptosis with no hTERT mRNA expression and TA modification in HT-144 cells, and induction of apoptosis, along with decrease in hTERT mRNA expression and TA in Me665/2/21 cells. No induction of apoptosis was observed in SK-Mel-5 and Me665/2/60 cells, although an early decrease in hTERT mRNA expression, and a minor increase of both hTERT mRNA expression and TA were found, respectively. CONCLUSIONS: Our results suggest that the effects of IFN-alpha on hTERT and TA can result from the induction of apoptosis, but they can also occur through a direct modulation of hTERT. We hypothesize that, depending on the cellular context rather than the IFNA-R status of the targeted cells, IFN-alpha can elicit an apoptotic cell death; furthermore, different pathways of apoptosis, not necessarily involving telomerase, can be put into motion.


Assuntos
Interferon-alfa/farmacologia , Melanoma/enzimologia , Neoplasias Cutâneas/enzimologia , Telomerase/metabolismo , Apoptose , Divisão Celular , Proteínas de Ligação a DNA , Humanos , Melanoma/patologia , RNA Mensageiro/metabolismo , Neoplasias Cutâneas/patologia , Células Tumorais Cultivadas
4.
Br J Dermatol ; 146(3): 399-408, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11952539

RESUMO

BACKGROUND: Telomere length is correlated with cellular ageing and immortalization processes. In some human cancers telomere length measurement has proved to be of diagnostic and prognostic value. Results comparable with the traditional terminal restriction fragment length determination by Southern blotting have been obtained in metaphase and interphase cells in some studies by fluorescence in situ hybridization (FISH) analysis; FISH additionally allows for the quantification of telomeres at the cellular level. OBJECTIVES: In this study, 32 melanocytic lesions were analysed by FISH, aiming at investigating possible telomere differences among various benign and malignant lesions and correlation with telomerase activity (TA) level. METHODS: FISH was performed on paraffin sections from six common naevi, eight Spitz naevi, 12 melanomas, six melanoma metastases and nine control samples of normal skin. Telomere mean maximum diameter (Feret max), area and number per nuclear area were calculated by image analysis on fluorescent images elaborated through KS400 and in situ imaging system (ISIS) for FISH analysis programs. Mean TA level was also calculated in all lesions and correlated with telomere parameters. RESULTS: Telomere number per nuclear area was significantly lower in melanomas and metastases than in benign common and Spitz naevi and in control skin (7 small middle dot24 +/- 3.3; 6.11 +/- 3 vs. 14.46 +/- 5.6; 16.92 +/- 7.8; and 12.59 +/- 3.4, respectively; P < 0 .001). No significant differences were found for the other telomere parameters. In common and Spitz naevi, telomere number was positively correlated with Feret max (P = 0.046 and P < 0.0001, respectively). TA was significantly higher in melanomas and metastases than in the other groups (70.18 +/- 25.2; 105.07 +/- 30 vs. 2.16 +/- 2.4; 2 .99 +/- 2.1; 2 +/- 1.2, respectively; P< or = 0. 001) and it was inversely correlated with telomere number per nuclear area in melanomas (P = 0.0041). No other significant correlations were found. CONCLUSIONS: Encouraging results have been obtained from quantitative telomere evaluation in the diagnosis of melanocytic lesions, although an analysis of a larger number of cases would be necessary to provide more reliable data. An extreme shortening of some telomeres probably results in the decrease of telomeric signals and the lower mean number of detectable telomeres in melanomas and metastases. In melanomas, telomere number per nuclear area is also inversely correlated with TA levels. Quantitative FISH of melanocytic lesions could give more specific information at the cellular level in telomere and telomerase fields of investigation.


Assuntos
Nevo/ultraestrutura , Neoplasias Cutâneas/ultraestrutura , Telômero/ultraestrutura , Estudos de Casos e Controles , Humanos , Processamento de Imagem Assistida por Computador , Hibridização in Situ Fluorescente , Melanoma/enzimologia , Melanoma/secundário , Melanoma/ultraestrutura , Proteínas de Neoplasias/metabolismo , Nevo/enzimologia , Nevo Pigmentado/enzimologia , Nevo Pigmentado/ultraestrutura , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/secundário , Telomerase/metabolismo
5.
Mycoses ; 45(1-2): 45-9, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11856437

RESUMO

A case of rhinocerebral zygomycosis due to Rhizopus oryzae, arising after trauma in a 53-year-old diabetic man, is reported. Diagnosis was based on histological and mycological examination. Fragments of the colonies were observed by scanning electron microscopy. This is the first case diagnosed in Tuscany.


Assuntos
Encefalopatias/microbiologia , Traumatismos Faciais/complicações , Mucormicose/microbiologia , Doenças Nasais/microbiologia , Doenças Profissionais/complicações , Rhizopus/isolamento & purificação , Encefalopatias/diagnóstico , Complicações do Diabetes , Evolução Fatal , Humanos , Itália , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade
6.
Pathol Res Pract ; 197(7): 475-81, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11482577

RESUMO

Solitary fibrous tumors (SFTs) are infrequent soft tissue neoplasms which are usually benign and surgically curable. However, their behavior is not always predictable, although several clinical and pathological criteria of malignancy have been established. In many cancers, including some soft tissue tumors, telomerase activity (TA) has been shown to be a new reliable pathological marker of malignancy. Overexpression of some cyclins is associated with higher degrees of malignancy and predictive of the clinical course. In this study, we evaluated TA, mitotic and apoptotic indices (MI, AI), and the expression of Ki-67, cyclins D1 and A in five typical and two clinicopathologically atypical SFTs, the latter two of which had also recurred. High TA was demonstrated in the two atypical cases, which also showed a higher labeling index to Ki-67, as well as higher cyclin D1 and A expression, and either none or very few apoptoses. We suggest that TA, Ki-67, cyclin expression, and AI be evaluated in SFTs as possible adjunctive pathological criteria of behavior.


Assuntos
Apoptose , Ciclina A/metabolismo , Ciclina D1/metabolismo , Antígeno Ki-67/metabolismo , Neoplasias de Tecido Fibroso/fisiopatologia , Neoplasias de Tecidos Moles/fisiopatologia , Telomerase/metabolismo , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
7.
Mol Genet Metab ; 73(3): 211-23, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11461188

RESUMO

Globoid cell leukodystrophy (Krabbe disease) is a severe leukodystrophy caused by mutations in the galactocerebrosidase (GALC) gene leading to extremely low (less than 5% of normal activity) GALC activity. Human patients include primarily severely affected infants as well as patients with a later onset of symptoms. The infants usually die before 2 years of age, but it is difficult to predict the clinical course in older patients. In addition to these patients, additional individuals identified in this laboratory have 10--20% of normal GALC activity measured in accessible tissues. These individuals have a wide range of clinical presentations involving neurological degeneration. On molecular analysis of the GALC gene they all have three or more mutations considered to be normal polymorphisms resulting in amino acid changes in the two copies of the GALC gene. In order to investigate the role these amino acid changes may play on clinical, biochemical, and pathological findings, a new transgenic mouse was generated by homologous recombination. After preliminary studies determined what effect each amino acid change had on mouse GALC activity in transient transfection experiments, mice containing a cysteine residue at codon 168 instead of histidine (H168C) were produced. These mice developed symptoms, but they were delayed by 10--15 days from the well-characterized twitcher (twi) mouse. They accumulated psychosine slightly slower than twi mice, showed pathological changes less severe than twi mice in the central and peripheral nervous systems, and live about 15 days longer than twi mice. They have large litters and will play a role in therapy trials using new procedures currently under development.


Assuntos
Galactosilceramidase/genética , Galactosilceramidase/metabolismo , Marcação de Genes , Leucodistrofia de Células Globoides/genética , Fatores Etários , Alelos , Animais , Northern Blotting , Peso Corporal , Encéfalo/metabolismo , Células COS , Códon , DNA Complementar/metabolismo , Modelos Animais de Doenças , Eletroporação , Vetores Genéticos , Homozigoto , Humanos , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica , Modelos Genéticos , Mutação , Polimorfismo Genético , Psicosina/biossíntese , Proteínas Recombinantes/genética , Recombinação Genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Distribuição Tecidual , Transfecção
8.
Hum Pathol ; 31(9): 1018-21, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11014565

RESUMO

Telomerase is an enzyme which synthesizes the telomeres, TTAGGG repeats at the end of vertebrate chromosomes. Its activity is suppressed in the majority of somatic cells, whereas it is detectable in most tumor cell lines and human cancers. Telomerase activity has been evaluated in many tumors for diagnostic purposes, and an increase thereof has been found with tumor progression. In our study we used anonisotopic polymerase chain reaction (PCR)-based TRAP (telomeric repeat amplification protocol) method to quantify the level of telomerase activity in a series of cutaneous melanocytic lesions. Thirty-three benign nevi, 8 dysplastic nevi, 38 malignant melanomas, and 4 melanoma metastases were analyzed. Mean relative telomerase activity was low in benign nevi (3.5+/-2.9), and significantly increased in dysplastic nevi (13.1+/-6.8), malignant melanomas (49.8+/-29.6), and metastases (121.2+/-11.2). In addition to the evaluation of telomerase activity as a possible diagnostic tool, its increase with tumor progression also suggest a prognostic role in cutaneous melanoma.


Assuntos
Melanócitos/enzimologia , Neoplasias Cutâneas/enzimologia , Telomerase/metabolismo , Divisão Celular , Primers do DNA/química , DNA de Neoplasias/análise , Síndrome do Nevo Displásico/enzimologia , Síndrome do Nevo Displásico/patologia , Humanos , Melanócitos/patologia , Melanoma/enzimologia , Melanoma/patologia , Melanoma/secundário , Reação em Cadeia da Polimerase , Pele/enzimologia , Pele/patologia , Neoplasias Cutâneas/patologia
9.
Hum Pathol ; 31(9): 1121-8, 2000 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11014581

RESUMO

Chorioamnionitis represents the leading cause of preterm birth and related pathologic conditions as well as of fetal death and frequently occurs in symptom-free mothers. Recent radiologic findings have indicated that thymus size is significantly reduced in preterm infants born to mothers with subclinical, histologically proven chorioamnionitis. However, an accurate morphologic description of the thymus gland in fetuses and neonates with chorioamnionitis is lacking, although it is known that infection and other stress processes may cause lymphocyte depletion in the thymuses of infants and older babies (acute stress involution). We describe morphologic modifications in the thymus of fetuses with histologically proven chorioamnionitis and newborn infants with chorioamnionitis and proven sepsis. The main findings included (1) decreased organ volume (ANOVA, P < .0024); (2) reduced corticomedullary ratio (P < 10(-6)); (3) significant changes in the relationship between thymic parenchyma and thymic interstitial tissue with resulting increased organ complexity (P = .03); (4) severe reduction of thymocytes; and (5) other degenerative processes such as monocyte/macrophage infiltration of Hassall's bodies. These results indicate that chorioamnionitis, with or without sepsis, is associated with significant morphologic modifications in the thymus. We wish to note that the described thymic pathology is only one aspect of the fetal systemic inflammatory response syndrome with which chorioamnionitis is associated.


Assuntos
Corioamnionite/patologia , Timo/patologia , Aborto Espontâneo , Aborto Terapêutico , Doença Aguda , Adulto , Atrofia , Biomarcadores/análise , Corioamnionite/complicações , Feminino , Idade Gestacional , Humanos , Imuno-Histoquímica , Recém-Nascido , Linfócitos/metabolismo , Linfócitos/patologia , Gravidez , Estudos Retrospectivos , Sepse/complicações , Sepse/patologia , Timo/metabolismo
10.
Int J Cancer ; 88(3): 411-6, 2000 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-11054670

RESUMO

Telomerase plays a key role in carcinogenesis. It is activated in most immortal cell lines and human cancers, including cutaneous melanoma (CM). Increased cell proliferation and deregulation of the cell cycle occur in human cancers. Links between telomerase activity (TA), cell proliferation, cell death and expression of cell-cycle regulators have not been extensively elucidated in CM. In this study, we investigated TA, mitotic index (MI), apoptotic index (AI), Ki-67 and nuclear positivity of cyclins D1 and A (Ki-67+ N/1,000, cyclin D1+N/1,000, cyclin A+N/1,000) in 42 primary cutaneous melanomas (PCMs). TA was detected in all cases and directly correlated with MI, Ki-67+N/1,000, cyclin D1+N/1,000 and cyclin A+N/1,000 (p < 0.001); it was not correlated with AI. When subdividing PCMs into radial and vertical growth phase melanomas (RGPMs, VGPMs), a correlation was maintained only with MI (p < 0.005) and cyclin D1 +N/1,000 (p < 0.005). Although MI and Ki-67+N/1,000 were highly correlated with cyclin D1+N/1,000 and cyclin A+N/1,000 (p < 0.001) when considering all cases together, a high correlation was found in the RGPM and VGPM groups between cyclin A+N/1,000 and Ki-67+N/1,000 only (p < 0.001), thus suggesting that cyclin A is more closely correlated with cell proliferation than cyclin D1. Our results further support the association between TA, tumor cell proliferation and cyclin D1 and A expression in PCM, though it is possible that links between TA and proliferation, on the one hand, and TA and cyclin D1 expression, on the other, might occur following various pathways.


Assuntos
Apoptose , Ciclina A/análise , Ciclina D1/análise , Antígeno Ki-67/análise , Melanoma/enzimologia , Mitose , Neoplasias Cutâneas/enzimologia , Telomerase/metabolismo , Humanos , Melanoma/patologia , Neoplasias Cutâneas/patologia
11.
Mol Genet Metab ; 70(1): 1-9, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10833326

RESUMO

Krabbe disease or globoid cell leukodystrophy is a disorder involving the white matter of the peripheral and central nervous systems. Mutations in the gene for the lysosomal enzyme galactocerebrosidase (GALC) result in low enzymatic activity and decreased ability to degrade galactolipids found almost exclusively in myelin. The pathological changes observed, including the presence of globoid cells and decreased myelin, appear to result from the toxic nature of psychosine and accumulation of galactosylceramide that cannot be degraded due to the GALC deficiency. Over 60 mutations have been identified in this gene. The great majority are disease-causing; however, a few are considered polymorphisms. While most patients present with symptoms within the first 6 months of life, others present later in life including adulthood. Even patients with the same genotype can have very different clinical presentations and course. The reason for this is not known. Treatment at this time is limited to hematopoietic stem cell transplantation that appears to slow the progression of the disease and improve the magnetic resonance images. Studies using stem cells and viral vectors to transduce transplantable cells are under way in model systems. In culture, oligodendrocytes from the twitcher mouse model can assume a normal appearance after differentiation if GALC activity is provided via viral transduction or uptake from donor cells. Therefore continued myelination and/or remyelination in patients will require supplying GALC activity by transplanted cells or viral vectors to still functional endogenous oligodendrocytes or transplantation of normal oligodendrocytes or stem cells that can differentiate into oligodendrocytes. Using the animal models these options can be explored.


Assuntos
Galactosilceramidase/genética , Leucodistrofia de Células Globoides/enzimologia , Animais , Galactosilceramidase/deficiência , Humanos , Leucodistrofia de Células Globoides/genética , Leucodistrofia de Células Globoides/terapia
12.
Anal Quant Cytol Histol ; 22(2): 133-8, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10800614

RESUMO

OBJECTIVE: To investigate the colorectal adenomacarcinoma sequence by biparametric DNA/nuclear protein flow cytometry with the aim of evaluating cell cycle modifications during carcinogenesis. STUDY DESIGN: Paraffin-embedded specimens of 27 adenomas with mild/moderate dysplasia, 20 adenomas with severe dysplasia/intramucosal adenocarcinomas, 28 adenocarcinomas and 14 normal colon mucosa specimens were analyzed by biparametric DNA/nuclear protein content flow cytometric analysis in order to evaluate cell cycle modifications during colorectal carcinogenesis. RESULTS: The mean G0-G1A fraction of the cell cycle was 50.6% (SD +/- 17.2), 25.7% (SD +/- 15.1), 27.8% (SD +/- 11.7) and 29% (SD +/- 13.8) for normal mucosa, adenomas with mild/moderate dysplasia, adenomas with severe dysplasia and adenocarcinomas, respectively. The difference between normal mucosa and the other groups was statistically significant (P < .05), while no significant differences were detectable between adenomas with different degrees of dysplasia and adenocarcinomas. CONCLUSION: Our results show a decrease in G0-G1A in adenomas with mild/moderate dysplasia, suggesting that modification of the cell cycle may represent an early step in colon carcinogenesis, and they support the hypothesis that disregulation of cell cycle-controlling genes is an early event in the adenoma-carcinoma sequence.


Assuntos
Adenocarcinoma/patologia , Transformação Celular Neoplásica/patologia , Neoplasias Colorretais/patologia , DNA de Neoplasias/metabolismo , DNA/metabolismo , Proteínas Nucleares/metabolismo , Adenocarcinoma/metabolismo , Adenoma/metabolismo , Adenoma/patologia , Aneuploidia , Ciclo Celular , Transformação Celular Neoplásica/metabolismo , Neoplasias Colorretais/metabolismo , Diploide , Citometria de Fluxo , Fase G1 , Fase G2 , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Mitose , Fase de Repouso do Ciclo Celular
15.
Am J Respir Crit Care Med ; 161(3 Pt 1): 1022-9, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10712358

RESUMO

Acute lung injury is frequent after severe peritonitis. The aim of this study was to investigate whether inhibition of the adhesion molecule CD11-CD18 on polymorphonuclear leukocytes (PMNs) would have any beneficial effects on pulmonary function and mortality in an animal model reproducing these clinical conditions. Acute peritonitis was induced in 36 rabbits by intraperitoneal injection of zymosan (0.6 g/kg) suspended in mineral oil; 20 were pretreated with a murine-specific IgG2a anti-CD18 monoclonal antibody, 16 (controls) with nonspecific purified murine IgG (1 mg/kg). The animals were followed for 10 d, then killed for histologic examination of the lungs. Blood samples were taken on Days 0, 1, 3, 7, and 10 for red blood cell (RBC), white blood cell (WBC), and platelet counts, pH, PO(2), PCO(2), carbon dioxide content (HCO(3)(-)) measurements, and renal and liver tests. Treatment with the anti-CD18 monoclonal antibody reduced mortality by approximately 40% (p < 0.05). PO(2) was higher in these treated animals than in the control animals throughout the study (p < 0.05 on Day 1, 3, and 10). On Day 1 control animals had significant leukopenia, whereas anti-CD18-treated animals had a moderate increase of the number of circulating WBC compared with baseline values (p < 0.05 between groups). The lungs of the anti-CD18-treated animals showed minor signs of inflammation and PMN infiltration whereas controls had interstitial and intra-alveolar edema and a large number of granulocytes. Quantification of PMNs by morphometry showed that there were constantly less granulocytes in the lungs of the animals treated with the anti-CD18 antibody (p < 0.001). PMN infiltration correlated with the levels of PO(2) (p < 0.001). Lung tissue of anti-CD18-treated rabbits contained less malonyldialdehyde, a by-product of membrane lipid peroxidation by PMN oxygen radicals (950 +/- 120 versus 1,710 +/- 450 pM/mg of protein) and, conversely, more of the antioxidant alpha-tocopherol (136 +/- 22 versus 40 +/- 9 ng/mg of protein), than the control rabbits (p < 0.01). In this particular model of ARDS the monoclonal antibody against the CD11-CD18 complex had a beneficial effect, reducing PMN infiltration and oxygen radical release in the lungs, preventing alveolocapillary membrane damage, improving gas exchange and, finally, significantly reducing mortality.


Assuntos
Anticorpos Monoclonais/farmacologia , Antígenos CD11/imunologia , Antígenos CD18/imunologia , Moléculas de Adesão Celular/imunologia , Imunoglobulina G/farmacologia , Insuficiência de Múltiplos Órgãos/patologia , Peritonite/patologia , Síndrome do Desconforto Respiratório/patologia , Animais , Pulmão/patologia , Masculino , Insuficiência de Múltiplos Órgãos/mortalidade , Peritônio/patologia , Peritonite/mortalidade , Coelhos , Síndrome do Desconforto Respiratório/mortalidade , Taxa de Sobrevida
16.
Acta Neuropathol ; 99(3): 271-6, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10663969

RESUMO

Muscle biopsy tissue from a patient with chronic hepatitis, who was hepatitis C virus (HCV) positive and showed slight weakness of the right arm and leg associated with increased serum creatine kinase levels, was studied using immunocytochemical and polymerase chain reaction (PCR) techniques. Muscle biopsy showed changes compatible with an inflammatory myopathy. Immunohistochemical studies included the use of monoclonal antibodies against human T lymphocytes, macrophages, immunoglobulins, major histocompatibility complex class I molecules (MHC-I), and the neoantigens of the terminal C5b-9 complement membrane attack complex (MAC). In addition to confirming the potential importance of cytotoxic T cells and MHC-I antigen expression in inducing muscle pathology, we demonstrated MAC deposition and the presence of HCV-RNA in the muscle of our patient, suggesting that direct involvement of the virus leading to complement activation might be important in inducing muscle damage.


Assuntos
Hepatite C Crônica/patologia , Miosite/patologia , Adulto , Complexo de Ataque à Membrana do Sistema Complemento/análise , Antígenos de Histocompatibilidade Classe I/análise , Humanos , Masculino , Microscopia Eletrônica , Músculo Esquelético/patologia , Músculo Esquelético/ultraestrutura , Reação em Cadeia da Polimerase , RNA Mensageiro/análise
17.
Histopathology ; 35(5): 418-22, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10583556

RESUMO

AIMS: To describe two new cases of papillary carcinoma of the thyroid with exuberant nodular fasciitis-like stroma, one of which was characterized by previously unreported transformation into a poorly differentiated lesion. Moreover, we explore the presence of TGF-beta to help to clarify the pathogenesis of the collagen formation. METHODS AND RESULTS: The case characterized by an aggressive behaviour exhibited areas of transformation into a poorly differentiated (insular) carcinoma of the thyroid. In both cases, as revealed by immunohistochemistry, neoplastic cells produced and secreted high amounts of TGF-beta. On the contrary, TGF-beta immunoreaction was never present in the normal thyroid or in papillary carcinomas without collagen bundles, while a weak, exclusively intracellular reaction was present in a patchy manner in cases showing intratumoral fibrous bundles. CONCLUSIONS: The rare variant of papillary thyroid carcinoma characterized by exuberant stroma may give rise to more aggressive lesions, as do other histotypes of differentiated thyroid carcinomas. TGF-beta, the fundamental cytokine which mediates scarring and activation of myofibroblasts, most probably induces the exuberant stroma.


Assuntos
Carcinoma Papilar/patologia , Queloide/patologia , Células Estromais/patologia , Neoplasias da Glândula Tireoide/patologia , Adulto , Idoso , Carcinoma Papilar/metabolismo , Carcinoma Papilar/cirurgia , Transformação Celular Neoplásica , Feminino , Humanos , Técnicas Imunoenzimáticas , Queloide/etiologia , Queloide/metabolismo , Masculino , Células Estromais/metabolismo , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/cirurgia , Fator de Crescimento Transformador beta/metabolismo
19.
Int J Cancer ; 83(2): 203-9, 1999 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-10471528

RESUMO

In view of recent knowledge on proteins regulating the cell cycle, we re-evaluated proliferative features of 98 diffusely growing non-Hodgkin's lymphomas. The combined use of 5 proliferation-associated variables (mitotic indices and percentages of Ki-67(+), p34(cdc2+), cyclin A(+) and cyclin B(+) cells) and their entry into a multivariate cluster analysis separated, without overlaps, the entire cohort into 3 groups (clusters) with (1) low, (2) intermediate and (3) high proliferative activity. Conversely, bivariate plots exposed considerable cluster overlaps. Multivariate stepwise discriminant analysis of all cases revealed a decreasing order of discriminant power for % Ki-67(+) cells > % p34(cdc2+) cells > mitotic index > % cyclin A(+) cells > % cyclin B(+) cells. The combined use of 2 variables only, mitotic index and % p34(cdc2+) cells, allowed a clear-cut separation of clusters 2 and 3. In bivariate plots, correlations were best between % Ki-67(+) cells and % cyclin A(+) cells and between mitotic indices and % cyclin B(+) cells. Except for chronic lymphocytic leukemias, immunocytomas and marginal zone lymphomas (all in cluster 1), individual lymphoma entities were distributed among at least 2 clusters. There was, however, a marked preponderance of mantle cell lymphomas and diffuse follicular center lymphomas in cluster 1 and of diffuse large B-cell lymphomas and peripheral T-cell lymphomas in cluster 2. Anaplastic large-cell lymphomas predominated in cluster 3 and responded best to therapy.


Assuntos
Proteína Quinase CDC2/biossíntese , Ciclina A/biossíntese , Ciclina B/biossíntese , Linfoma não Hodgkin/metabolismo , Linfoma não Hodgkin/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína Quinase CDC2/fisiologia , Divisão Celular , Criança , Análise por Conglomerados , Estudos de Coortes , Ciclina A/fisiologia , Ciclina B/fisiologia , Análise Discriminante , Feminino , Humanos , Linfoma não Hodgkin/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estudos Retrospectivos
20.
Virchows Arch ; 435(1): 62-6, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10431848

RESUMO

We report an intimal sarcoma presenting as an aortic aneurysm. A 68-year-old man suffered from chest pain and speech disturbance. Computed tomography showed a sacciform aneurysm of the aorta, which was resected, revealing a polypoid tumour measuring 1.5x2x2.5 cm projecting into the lumen. This proved to be a poorly differentiated high-grade sarcoma having morphological, immunophenotypic and ultrastructural features consistent with rhabdomyosarcomatous differentiation. Primary sarcomas of the aorta are extremely rare. Many cases have been diagnosed as "intimal" on the basis of their site of origin, and they are not easy to classify from their histological pattern. Electron microscopy and the use of a more comprehensive panel of immunohistochemical markers should be applied in the histological classification of"intimal" sarcoma.


Assuntos
Aorta Torácica/patologia , Rabdomiossarcoma/patologia , Sarcoma/patologia , Túnica Íntima/patologia , Neoplasias Vasculares/patologia , Idoso , Aneurisma Aórtico/complicações , Biomarcadores Tumorais/metabolismo , Diferenciação Celular , Humanos , Masculino , Microscopia Eletrônica , Rabdomiossarcoma/complicações , Rabdomiossarcoma/metabolismo , Rabdomiossarcoma/ultraestrutura , Sarcoma/complicações , Sarcoma/diagnóstico por imagem , Sarcoma/metabolismo , Sarcoma/ultraestrutura , Tomografia Computadorizada por Raios X , Neoplasias Vasculares/complicações , Neoplasias Vasculares/metabolismo , Neoplasias Vasculares/ultraestrutura
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