Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 64
Filtrar
1.
J Hosp Infect ; 139: 192-200, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37451408

RESUMO

BACKGROUND: Vancomycin-resistant Enterococcus faecium (VRE) is a leading cause of nosocomial infection, driven by its ability to spread between patients and persist in the hospital environment. AIM: To investigate the impact of a long-established cardiothoracic hospital moving to new premises with close to 100% single-occupancy rooms on the rates of environmental contamination and infection or colonization by VRE. METHODS: Prospective environmental surveillance for VRE was conducted at five time-points between April and November 2019, once in the original building, and four times in the new building. Incidence rate ratios (IRRs) of VRE infection/colonization were determined for the one-year period before and after the hospital move, and compared to a nearby hospital. FINDINGS: In the original location, the first environmental screen found 29% VRE positivity. The following four screens in the new location showed a significant reduction in positivity (1-6%; P<0.0001). The VRE infection/colonization rates were halved in the new location (IRR: 0.56; 95% confidence interval: 0.38-0.84), compared to the original location, contrasting with an increase in a nearby hospital (1.62; 1.17-2.27) over the same time-period. Genomic analysis of the environmental isolates was consistent with reduced transmission in the new hospital. CONCLUSION: The use of single-occupancy rooms was associated with reduced environmental contamination with VRE, and lower transmission and isolation of VRE from clinical samples. The cost-effectiveness of single-occupancy room hospitals in reducing healthcare-associated infections should be reassessed in the context of operational costs of emerging pandemic and increasing antimicrobial resistance threats.


Assuntos
Infecção Hospitalar , Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Enterococos Resistentes à Vancomicina , Humanos , Vancomicina , Enterococcus faecium/genética , Incidência , Estudos Prospectivos , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/prevenção & controle , Enterococos Resistentes à Vancomicina/genética , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Hospitais , Genômica
2.
Sci Transl Med ; 9(413)2017 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-29070701

RESUMO

Genome sequencing has provided snapshots of the transmission of methicillin-resistant Staphylococcus aureus (MRSA) during suspected outbreaks in isolated hospital wards. Scale-up to populations is now required to establish the full potential of this technology for surveillance. We prospectively identified all individuals over a 12-month period who had at least one MRSA-positive sample processed by a routine diagnostic microbiology laboratory in the East of England, which received samples from three hospitals and 75 general practitioner (GP) practices. We sequenced at least 1 MRSA isolate from 1465 individuals (2282 MRSA isolates) and recorded epidemiological data. An integrated epidemiological and phylogenetic analysis revealed 173 transmission clusters containing between 2 and 44 cases and involving 598 people (40.8%). Of these, 118 clusters (371 people) involved hospital contacts alone, 27 clusters (72 people) involved community contacts alone, and 28 clusters (157 people) had both types of contact. Community- and hospital-associated MRSA lineages were equally capable of transmission in the community, with instances of spread in households, long-term care facilities, and GP practices. Our study provides a comprehensive picture of MRSA transmission in a sampled population of 1465 people and suggests the need to review existing infection control policy and practice.


Assuntos
Infecções Comunitárias Adquiridas/microbiologia , Infecções Comunitárias Adquiridas/transmissão , Genoma Bacteriano , Hospitais , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/transmissão , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Infecções Comunitárias Adquiridas/epidemiologia , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/transmissão , Geografia , Humanos , Lactente , Recém-Nascido , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Pessoa de Meia-Idade , Filogenia , Infecções Estafilocócicas/epidemiologia , Reino Unido , Adulto Jovem
4.
Cell Death Dis ; 5: e1279, 2014 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-24901050

RESUMO

Diffusely infiltrating gliomas are among the most prognostically discouraging neoplasia in human. Temozolomide (TMZ) in combination with radiotherapy is currently used for the treatment of glioblastoma (GBM) patients, but less than half of the patients respond to therapy and chemoresistance develops rapidly. Epigenetic silencing of the O(6)-methylguanine-DNA methyltransferase (MGMT) has been associated with longer survival in GBM patients treated with TMZ, but nuclear factor κB (NF-κB)-mediated survival signaling and TP53 mutations contribute significantly to TMZ resistance. Enhanced NF-κB is in part owing to downregulation of negative regulators of NF-κB activity, including Tumor necrosis factor alpha-induced protein 3 (TNFAIP3) and NF-κB inhibitor interacting RAS-like 2 (NKIRAS2). Here we provide a novel mechanism independent of TP53 and MGMT by which oncogenic miR-125b confers TMZ resistance by targeting TNFAIP3 and NKIRAS2. GBM cells overexpressing miR-125b showed increased NF-κB activity and upregulation of anti-apoptotic and cell cycle genes. This was significantly associated with resistance of GBM cells to TNFα- and TNF-related inducing ligand-induced apoptosis as well as resistance to TMZ. Conversely, overexpression of anti-miR-125b resulted in cell cycle arrest, increased apoptosis and increased sensitivity to TMZ, indicating that endogenous miR-125b is sufficient to control these processes. GBM cells overexpressing TNFAIP3 and NKIRAS2 were refractory to miR-125b-induced apoptosis resistance as well as TMZ resistance, indicating that both genes are relevant targets of miR-125b. In GBM tissues, high miR-125b expression was significantly correlated with nuclear NF-κB confirming that miR-125b is implicated in NF-κB signaling. Most remarkably, miR-125b overexpression was clearly associated with shorter overall survival of patients treated with TMZ, suggesting that this microRNA is an important predictor of response to therapy.


Assuntos
Apoptose , Proteínas de Ligação a DNA/metabolismo , Dacarbazina/análogos & derivados , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , MicroRNAs/metabolismo , Proteínas Nucleares/metabolismo , RNA Neoplásico/farmacologia , Proteínas ras/metabolismo , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Dacarbazina/farmacologia , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , MicroRNAs/genética , Proteínas Nucleares/genética , Temozolomida , Proteína 3 Induzida por Fator de Necrose Tumoral alfa , Proteínas ras/genética
6.
Histol Histopathol ; 23(10): 1185-93, 2008 10.
Artigo em Inglês | MEDLINE | ID: mdl-18712670

RESUMO

Primary perivascular epithelioid cell tumor (PEComa) of the liver is a very rare example of an emerging family of hepatic PEC tumors. Only few cases have been described so far. We report the case of a large but benign hepatic PEComa in a 53-year-old man without signs of tuberous sclerosis. In contrast to recently described PEC-derived liver tumors in children and young adults, this neoplasm was not related to the hepatic ligaments but had developed deeply within the liver substance. The neoplastic cells displayed the complete phenotype typical for PEComas, i.e. reactivity for several melanoma markers and for smooth muscle actin. The unique relationship of myoid tumor cells to the adventitia of blood vessels prompted us, in comparison with published findings obtained with angiomyolipomas, to comment on the possible origin of the still enigmatic perivascular epithelioid cells.


Assuntos
Angiomiolipoma/patologia , Células Epitelioides/patologia , Neoplasias Hepáticas/patologia , Fígado/patologia , Angiomiolipoma/irrigação sanguínea , Angiomiolipoma/classificação , Proliferação de Células , Humanos , Imuno-Histoquímica , Ligamentos/patologia , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/classificação , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fenótipo , Terminologia como Assunto
7.
Ann Oncol ; 19(7): 1288-1292, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18349029

RESUMO

BACKGROUND: To determine the activity and tolerability of adding cetuximab to the oxaliplatin and capecitabine (XELOX) combination in first-line treatment of metastatic colorectal cancer (MCC). PATIENTS AND METHODS: In a multicenter two-arm phase II trial, patients were randomized to receive oxaliplatin 130 mg/m(2) on day 1 and capecitabine 1000 mg/m(2) twice daily on days 1-14 every 3 weeks alone or in combination with standard dose cetuximab. Treatment was limited to a maximum of six cycles. RESULTS: Seventy-four patients with good performance status entered the trial. Objective partial response rates after external review and radiological confirmation were 14% and 41% in the XELOX and in the XELOX + Cetuximab arm, respectively. Stable disease has been observed in 62% and 35% of the patients, with 76% disease control in both arms. Cetuximab led to skin rash in 65% of the patients. The median overall survival was 16.5 months for arm A and 20.5 months for arm B. The median time to progression was 5.8 months for arm A and 7.2 months for arm B. CONCLUSION: Differences in response rates between the treatment arms indicate that cetuximab may improve outcome with XELOX. The correct place of the cetuximab, oxaliplatin and fluoropyrimidine combinations in first-line treatment of MCC has to be assessed in phase III trials.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Antineoplásicos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais Humanizados , Antineoplásicos/administração & dosagem , Cetuximab , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/patologia , Esquema de Medicação , Exantema/induzido quimicamente , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica/diagnóstico por imagem , Metástase Neoplásica/tratamento farmacológico , Metástase Neoplásica/patologia , Compostos Organoplatínicos/administração & dosagem , Compostos Organoplatínicos/efeitos adversos , Oxaliplatina , Radiografia , Suíça , Fatores de Tempo , Resultado do Tratamento
8.
Kidney Int ; 69(2): 358-68, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16408127

RESUMO

Chronic renal allograft rejection is characterized by alterations in the extracellular matrix compartment and in the proliferation of various cell types. These features are controlled, in part by the metzincin superfamily of metallo-endopeptidases, including matrix metalloproteinases (MMPs), a disintegrin and metalloproteinase (ADAM) and meprin. Therefore, we investigated the regulation of metzincins in the established Fisher to Lewis rat kidney transplant model. Studies were performed using frozen homogenates and paraffin sections of rat kidneys at day 0 (healthy controls) and during periods of chronic rejection at day +60 and day +100 following transplantation. The messenger RNA (mRNA) expression was examined by Affymetrix Rat Expression Array 230A GeneChip and by real-time Taqman polymerase chain reaction analyses. Protein expression was studied by zymography, Western blot analyses, and immunohistology. mRNA levels of MMPs (MMP-2/-11/-12/-14), of their inhibitors (tissue inhibitors of metalloproteinase (TIMP)-1/-2), ADAM-17 and transforming growth factor (TGF)-beta1 significantly increased during chronic renal allograft rejection. MMP-2 activity and immunohistological staining were augmented accordingly. The most important mRNA elevation was observed in the case of MMP-12. As expected, Western blot analyses also demonstrated increased production of MMP-12, MMP-14, and TIMP-2 (in the latter two cases as individual proteins and as complexes). In contrast, mRNA levels of MMP-9/-24 and meprin alpha/beta had decreased. Accordingly, MMP-9 protein levels and meprin alpha/beta synthesis and activity were downregulated significantly. Members of metzincin families (MMP, ADAM, and meprin) and of TIMPs are differentially regulated in chronic renal allograft rejection. Thus, an altered pattern of metzincins may represent novel diagnostic markers and possibly may provide novel targets for future therapeutic interventions.


Assuntos
Regulação da Expressão Gênica , Rejeição de Enxerto , Transplante de Rim , Metaloproteinases da Matriz/genética , Metaloendopeptidases/genética , Proteínas ADAM/genética , Proteína ADAM17 , Animais , Biomarcadores , Doença Crônica , Rejeição de Enxerto/diagnóstico , Rejeição de Enxerto/terapia , Masculino , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Endogâmicos F344 , Ratos Endogâmicos Lew , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Inibidor Tecidual de Metaloproteinase-2/genética , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta1 , Transplante Homólogo
9.
Ann Oncol ; 16(9): 1477-87, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16012182

RESUMO

BACKGROUND: Ovarian cancer is frequently lethal despite aggressive multimodal therapy, and new therapies are therefore needed. Retinoids are potential candidate drugs: they prevent the development of ovarian carcinoma and enhance the efficacy of cytotoxic drugs in ovarian cancer cells. At present, little is known about the retinoid receptor expression in ovarian cancer. PATIENTS AND METHODS: The retinoid receptors comprise two classes, retinoic acid receptors (RARs) and retinoid X receptors (RXRs), each with three subclasses, alpha, beta and gamma. We investigated the expression of the subtypes RARalpha, RARgamma, RXRalpha and RXRbeta by immunohistochemistry in ovarian cancers of 80 patients, and assessed their prognostic significance. In addition, we quantified the expression of retinoid receptor mRNA using real-time PCR and correlated the results with clinical characteristics. RESULTS: RARalpha and RXRbeta were highly expressed in a majority of ovarian cancers, particularly in advanced stages. High expression of RARalpha was an independent negative prognostic factor of survival in addition to FIGO stage, age and p53 accumulation. The mRNA expression of retinoid receptors did not correlate with clinical properties of the tumors. CONCLUSIONS: Retinoic acid receptors are frequently and strongly expressed in epithelial ovarian cancer and may be indicators of an adverse prognosis. This study provides the molecular basis for the therapeutic use of retinoids in ovarian cancer.


Assuntos
Neoplasias Ovarianas/metabolismo , Receptores do Ácido Retinoico/metabolismo , Idoso , Sequência de Bases , Primers do DNA , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Prognóstico , RNA Mensageiro/genética , Receptores do Ácido Retinoico/classificação , Receptores do Ácido Retinoico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Br J Dermatol ; 151(4): 903-6, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15491436

RESUMO

Lentigo maligna (LM) is an in situ melanoma which usually occurs in sun-damaged skin on the head and neck of elderly patients. Depending on the anatomical site and its size treatment of LM can be problematic and usually includes surgical excision or radiotherapy. Recent reports indicate that topical imiquimod may be an effective treatment. However, no data on the underlying immune response in the skin during treatment of LM with topical imiquimod are available so far. We report a 62-year-old caucasian woman with a histologically verified LM which was successfully treated with topical imiquimod 5% cream. Skin biopsy specimens were obtained before, during (at week 10) and 4 weeks after cessation of topical treatment with imiquimod 5% cream. Histological and immunohistochemical examination was performed in order to detect residual atypical melanocytes and to characterize the inflammatory infiltrate. A complete clinical and histological clearance of the skin lesion was achieved, with no recurrence up to 9 months after the end of treatment. During topical application of imiquimod 5% cream a depletion of epidermal and dermal CD1a+ dendritic cells was observed. The inflammatory infiltrate consisted of CD68+ macrophages and mainly of CD3+ T cells with a slight predominance of CD8+ T cells. An enhanced expression of granzyme B and TIA-1 was also noted particularly in the epidermis and near the dermoepidermal junction. In conclusion, our data indicate that imiquimod 5% cream induces a cytotoxic T-cell-mediated immune response in situ which may account for the complete destruction of the malignant melanocytes in LM. Further clinical trials and longer follow-up periods on the use of imiquimod for LM are warranted.


Assuntos
Aminoquinolinas/uso terapêutico , Antineoplásicos/uso terapêutico , Neoplasias Faciais/tratamento farmacológico , Sarda Melanótica de Hutchinson/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Subpopulações de Linfócitos T/efeitos dos fármacos , Neoplasias Faciais/imunologia , Feminino , Humanos , Sarda Melanótica de Hutchinson/imunologia , Imiquimode , Pessoa de Meia-Idade , Neoplasias Cutâneas/imunologia
11.
Gut ; 53(10): 1431-6, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15361490

RESUMO

BACKGROUND AND AIMS: Many neuroendocrine gastrointestinal tumours express receptors for the regulatory peptide somatostatin. Among the five existing somatostatin receptor (sst) subtypes, sst2A is the most frequently expressed in these tumours. However, little information is available about the cellular location of sst2A in corresponding non-neoplastic epithelial tissues. METHODS: We searched for sst2A immunoreactive cells in non-neoplastic gastrointestinal tissues, and evaluated their number and immunohistochemical characteristics with neuroendocrine markers. RESULTS: The gastric antrum showed numerous sst2A cells, situated in the epithelium, corresponding to gastrin containing neuroendocrine cells, while the gastric corpus was largely devoid of sst2A cells, including enterochromaffin-like cells. The remaining foregut, namely the duodenum and proximal jejunum, also contained a large number of sst2A cells, all being neuroendocrine cells and many of them characterised as gastrin cells. Sst2A cells were also detected in the midgut, in low numbers in the epithelium of the distal jejunum and ileum, but not in the appendix vermiformis, the caecum, or the hindgut, despite the large number of neuroendocrine cells present in this area. In addition, sst2A cells were found in the whole gastrointestinal tract in the myenteric and submucosal plexus. CONCLUSIONS: While sst2A receptors on antral gastrin cells presumably mediate somatostatin inhibition of gastrin secretion, the effects of somatostatin on motility and ion transport in the lower gastrointestinal tract may be mediated by sst2A receptors in the neural plexus. These data provide a molecular basis for the physiological actions of somatostatin in human gastrointestinal tissue.


Assuntos
Células Enteroendócrinas/metabolismo , Receptores de Somatostatina/metabolismo , Mucosa Gástrica/metabolismo , Humanos , Técnicas Imunoenzimáticas , Mucosa Intestinal/metabolismo , Intestino Delgado/metabolismo , Antro Pilórico/metabolismo , Somatostatina/fisiologia
12.
Ann N Y Acad Sci ; 1014: 132-6, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15153427

RESUMO

Many neuroendocrine gastrointestinal and lung tumors express sst2A somatostatin receptors. Because the cellular location of sst2A in the corresponding non-neoplastic tissue is unknown, we searched for sst2A immuno-reactive cells and characterized their type in these tissues using a highly specific sst2A antibody (R2-88). Epithelial sst2A cells, identified as neuroendocrine, gastrin-producing cells, were found in large numbers in the antrum and the duodenum, but not in the gastric corpus. They were also present in the proximal jejunum, rarely noted in the distal jejunum and ileum, and absent in the large intestine and the appendix vermiformis. Moreover, sst2A cells were found abundantly in the neural plexus. sst2A receptors on antral gastrin cells could mediate somatostatin inhibition on gastrin secretion, whereas those in the neural plexus could mediate somatostatin effects on motility and ion transport in the lower gastrointestinal tract. Rare sst2A cells in bronchi and bronchioles located basally and parabasally in the gastrointestinal epithelium were detected that could represent stem/progenitor cells. It is currently not clear whether and which of the identified sst2A cells are at the origin of sst2A-positive neuroendocrine gut or lung tumors.


Assuntos
Mucosa Intestinal/metabolismo , Neoplasias Intestinais/metabolismo , Neoplasias Pulmonares/metabolismo , Receptores de Somatostatina/metabolismo , Mucosa Respiratória/metabolismo , Gastrinas/metabolismo , Humanos , Imuno-Histoquímica , Mucosa Intestinal/patologia , Neoplasias Intestinais/patologia , Neoplasias Pulmonares/patologia , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/patologia , Mucosa Respiratória/patologia
13.
Br J Surg ; 90(12): 1565-72, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14648737

RESUMO

BACKGROUND: There is increasing evidence that immune mechanisms may be crucial in the development of alcoholic chronic pancreatitis. However, it is not known whether differences in underlying aetiology influence the inflammatory reaction in patients with chronic pancreatitis. The histological features and the pattern of inflammatory cell infiltration were studied in three aetiological forms of chronic pancreatitis: alcoholic, idiopathic and tropical pancreatitis. METHODS: Forty-three patients, ten with alcoholic, 12 with idiopathic and 21 with tropical chronic pancreatitis, were evaluated for the pattern of pancreatic inflammatory cell infiltration and histological features. Ten organ donors served as controls. Haematoxylin and eosin-stained tissue sections were used for histological evaluation. For immunohistochemical characterization of the inflammatory reaction, four antibodies-CD4, CD8, CD45 and CD68-were used. Quantitative evaluation of the various cell infiltrates was performed with computer-assisted image analysis. The inflammatory cell infiltration pattern was also evaluated. RESULTS: The degree of endophlebitis and the overall density of plasma cells were greater in tropical than in alcoholic chronic pancreatitis. The grade of intralobular fibrosis was significantly higher in tropical chronic pancreatitis compared with the idiopathic form. No significant quantitative differences in the specific cellular infiltrates (CD4, CD8, CD45, CD68) were observed in the three different groups. However, the perivascular inflammation number score was significantly higher in alcoholic compared with idiopathic pancreatitis (P = 0.037), and the perivascular inflammation area score was significantly lower in idiopathic than in alcoholic (P = 0.024) or tropical (P = 0.020) pancreatitis. CONCLUSION: Different aetiological forms of chronic pancreatitis result in similar histological features and a comparable inflammatory cell reaction, indicating that the disease, independent of the underlying aetiology, reaches a common immunological stage beyond which it appears to progress as a single distinctive entity.


Assuntos
Pancreatite/patologia , Adulto , Doença Crônica , Eosinófilos/patologia , Feminino , Fibrose/patologia , Humanos , Masculino , Pancreatite Alcoólica/patologia , Plasmócitos/patologia
14.
J Clin Oncol ; 21(11): 2085-93, 2003 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12775733

RESUMO

PURPOSE: Cyclin D1 is overexpressed in almost 60% of resectable non-small-cell lung cancer (NSCLC). In the absence of cyclin D1 gene amplification, overexpression is characterized by allelic imbalanced transcript levels. METHODS: The aims were to study cyclin D1 expression by immunohistochemistry and allelic balance of transcripts in tumor-free bronchial epithelia from patients with resectable NSCLC by using monoclonal antibodies (48 patients and 288 sites), microdissection/reverse transcriptase polymerase chain reaction/restriction fragment length polymorphism analyses (24 patients and 144 sites). Derived data were related to patient characteristics-in particular, smoking habits. RESULTS: In 167 (58%) of 288 sites, cyclin D1 was overexpressed, with cytoplasmic and nuclear sublocalization in 53% and 7% of all sites, respectively. Nuclear overexpression was more frequent in premalignant versus normal or hyperplastic epithelia (55% v 3%; P <.0001). Allele-specific expression imbalances were found in 69 (48%) of 144 sites; in particular, those in which cyclin D1 was overexpressed (P =.004). In 14 (58%) of 24 patients, balanced or imbalanced transcript ratios and degree of expression were consistent at all sites for the same patient, whereas in another 10 patients, transcript balances and cyclin D1 expression patterns varied across the sites. Nuclear cyclin D1 expression in at least one site (14 of 48 patients) was linked to heavy smoking (> 40 pack-years; P =.02) and shorter overall survival (P =.01). CONCLUSION: Allele-specific, probably damage-driven, deregulation of the cyclin D1 gene may precede and perhaps facilitate the spread of preneoplastic clones across the bronchial epithelial surface in a significant number of patients. Cyclin D1 expression at multiple bronchial sites may identify a subgroup of heavy-smoking patients with poor outcome.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Ciclina D1/biossíntese , Ciclina D1/genética , Neoplasias Pulmonares/metabolismo , Mucosa Respiratória/metabolismo , Fumar/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , Modelos de Riscos Proporcionais , Estudos Prospectivos , Estatísticas não Paramétricas , Taxa de Sobrevida , Suíça/epidemiologia
15.
Dig Liver Dis ; 34(10): 748-53, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12469803

RESUMO

The case of a variant of hepatocellular carcinoma is described, which, based on its unique histology, we propose to term, medullary-like hepatocellular carcinoma. It developed in a 56-year-old male patient with liver cirrhosis, and consisted of large, amphophilic cells with a solid growth pattern. The tumour was densely infiltrated with lymphocytes and plasma cells. Lymphocytes formed a mixture of B and T cells, and plasma cells were polytypic. In addition, numerous S-100 protein-reactive stellate cells were observed at the tumour border, where marked apoptosis of hepatocellular carcinoma cells was evident. In areas of dense lymphoplasmacytic infiltration, part of the tumour cells had lost their intercellular connections and their beta-catenin reactivity. Some tumour cells expressed FasL, but not Fas. The tumour exhibited several foci of regression, showing small remnants of damaged tumour cells within dense infiltrations. The patient is alive without evidence of disease 25 months after resection. Medullary-like hepatocellular carcinoma is a lesion which mimics several features known for other medullary carcinomas, including a marked immune response which may be responsible for partial regression of this tumour.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Fígado/patologia , Humanos , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Regressão Neoplásica Espontânea
16.
Gut ; 51(4): 574-8, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12235083

RESUMO

BACKGROUND AND AIM: The aim of this study was to systematically analyse the pattern of regeneration in human acute pancreatitis by testing whether pancreatic stellate cells, their myofibroblastic offspring, and pancreatic ductules are involved in the regenerative process. PATIENTS AND METHODS: Between January 1994 and November 2000, 24 necrosectomy specimens containing vital tissue were obtained for pathological examination. Formalin fixed tissue samples were routinely processed and immunostained for cytokeratins 7 and 19, smooth muscle actin, desmin, Ki-67, and CD68. Pancreatic tissue from organ donors served as normal controls. RESULTS: Necrosectomy specimens were obtained between 11 and 41 days after the onset of symptoms. In vital areas of necrosectomy samples, spherical hypercellular spheres consisting of loose vascular connective tissue occurred, in part showing duct-like profiles which sprouted from remnant exocrine tissue almost perpendicular to the periphery of the spheres. In normal tissue, only a few stellate cells and myofibroblasts were present around ducts and ductules. In contrast, numerous stellate cells and myofibroblasts were detected in the hypercellular regenerative spheres after acute pancreatitis, both being situated within the loose tissue and forming compact periductular sheaths. Stellate cells/myofibroblasts and ductule cells exhibited increased proliferative activity. CONCLUSIONS: Pancreatic stellate cells and their activated myofibroblastic offspring may participate in regeneration after acute necrotising pancreatitis in humans. Time course studies are needed to further strengthen this regeneration concept.


Assuntos
Pâncreas/citologia , Pâncreas/fisiologia , Pancreatite Necrosante Aguda/fisiopatologia , Regeneração/fisiologia , Actinas/análise , Adulto , Idoso , Divisão Celular , Feminino , Humanos , Queratinas/análise , Masculino , Pessoa de Meia-Idade , Pancreatite Necrosante Aguda/patologia
17.
Gut ; 50(5): 682-6, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11950816

RESUMO

BACKGROUND AND AIMS: Among various causes, nerve alterations and neuroimmune interactions have been suggested to participate in the generation of pain in chronic pancreatitis (CP). In this study, we compared neural changes and the pattern of perineural inflammatory cell infiltrates in three different aetiological forms of CP (alcoholic, idiopathic, and tropical) and evaluated whether differences exist between these groups. PATIENTS AND METHODS: A total of 35 patients with CP (12 tropical, 12 idiopathic, and 11 alcoholic) were included. Ten normal pancreatic tissues obtained from healthy organ donors served as controls. In all samples, the number of nerves, area of neural tissue, nerve size, and percentage of neural tissue and perineural inflammatory cell infiltrates were analysed histologically. RESULTS: The median number of nerves per 10 mm2 tissue area was 2.3, 4.3, 4.4, and 2.6 in the normal pancreas, alcoholic CP, idiopathic CP, and tropical CP, respectively. Median area of neural tissue per 10 mm2 was 2550, 21 803, 18 595, and 24 666 microm2 in the normal pancreas, alcoholic CP, idiopathic CP, and tropical CP, respectively. Median nerve diameter was 36.85 microm in the normal pancreas, 80.6 microm in alcoholic CP, 68.95 microm in idiopathic CP, and 93.05 microm in tropical CP. In comparison with normal controls, all of these parameters were significantly increased except the number of nerves in tropical CP. For all parameters there were no significant differences between alcoholic, idiopathic, and tropical CP. When the degree of perineural inflammation was evaluated, no differences were observed among the three CP groups. CONCLUSIONS: Independent of the underlying aetiology, CP is associated with an increase in neural tissue, and neural alterations occur in a similar fashion irrespective of the type of initiating event.


Assuntos
Pâncreas/inervação , Pancreatite/patologia , Adulto , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/análise , Pancreatite/etiologia , Pancreatite/metabolismo , Pancreatite Alcoólica/metabolismo , Pancreatite Alcoólica/patologia , Sistema Nervoso Periférico/patologia , Tioléster Hidrolases/análise , Ubiquitina Tiolesterase
18.
Hum Pathol ; 32(11): 1174-83, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11727255

RESUMO

Chronic pancreatitis (CP) is characterized by mononuclear inflammatory cell infiltration and replacement of the destroyed parenchyma by fibrous tissue. Recently, mast cells have been implicated in chronic inflammatory processes with fibrous tissue deposition. Therefore, the number and distribution of mast cells and their state of activation were evaluated in 12 normal specimens and in 46 specimens of CP with different causes (alcoholic, tropical, and idiopathic). Furthermore, the presence of stem cell factor (SCF), the main mast cell growth factor, and of its receptor, c-kit, was also assessed. In CP tissues, mast cells were localized both in the fibrotic areas and in the residual acinar parenchyma. The total number of mast cells was significantly higher in CP than in the normal pancreas (P < .0001) and correlated positively with the extent of fibrosis and the intensity of inflammation. Immunoglobulin E (IgE)-dependent mast cell activation was higher in CP than in the normal pancreas. No differences in mast cell number or IgE positivity were found among the 3 causes of CP. SCF-and c-kit immunoreactive mast cells were mostly localized in fibrous tissue and around regenerating ducts, which were also positive for c-kit but were negative for SCF. These results suggest that mast cells, activated by an IgE-dependent mechanism and/or by an SCF-c-kit autocrine loop, are a relevant component of the inflammatory infiltrate in CP, independent of the underlying cause. Their localization near degenerating acini and regenerating ducts might indicate that they play a crucial role in tissue destruction and remodeling in CP.


Assuntos
Mastócitos/citologia , Mastócitos/imunologia , Pancreatite/imunologia , Pancreatite/patologia , Adolescente , Adulto , Western Blotting , Contagem de Células , Doença Crônica , Quimases , Feminino , Humanos , Imunoglobulina E/análise , Imunoglobulina E/imunologia , Imuno-Histoquímica , Masculino , Mastócitos/química , Pessoa de Meia-Idade , Testes de Precipitina , Proteínas Proto-Oncogênicas c-kit/análise , Proteínas Proto-Oncogênicas c-kit/imunologia , Serina Endopeptidases/análise , Serina Endopeptidases/imunologia , Coloração e Rotulagem , Fator de Células-Tronco/análise , Fator de Células-Tronco/imunologia , Triptases
19.
Clin Exp Allergy ; 31(9): 1398-408, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11591190

RESUMO

BACKGROUND: The most frequent side-effects of drug therapy are skin eruptions. Their pathomechanism is rather unclear. OBJECTIVE: In this prospective study we investigated the T cell activation and drug specificity in different forms of drug-induced exanthemas from 22 patients. METHODS: During acute drug allergy, liver parameters and T cell subset activation in the circulation (up-regulation of CD25 and HLA-DR) were evaluated and skin biopsies of the acute lesion performed. After recovery, the causative drug was identified by lymphocyte transformation (LTT) and scratch-patch tests. RESULTS: Seventeen of 22 (17/22) patients had maculo-papular exanthema, 4/22 bullous exanthema and 1/22 urticaria. The causative drugs were mainly antibiotics, anti-epileptics and anti-hypertensives. Up-regulation of HLA-DR on circulating CD4(+) and/or CD8(+) T cells was detected in 17 patients, being most marked in patients with bullous reactions or hepatic involvement. The LTT was positive in 14/21 analysed and the patch test in 7/15. All patients showed lymphocytic infiltration in the skin biopsy of the acute lesion. Generally CD4(+) T cells dominated; a higher percentage of circulating CD8(+) T cells was found in patients with bullous skin reactions or hepatic involvement. CONCLUSION: Our data demonstrate activation and drug specificity of T cells in drug-induced skin eruptions. A predominant CD8(+) T cell activation leads to more severe (bullous) skin symptoms or liver involvement, while predominant activation of CD4(+) cells elicits mainly maculo-papular reactions.


Assuntos
Toxidermias/etiologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/fisiologia , Administração Cutânea , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos/imunologia , Toxidermias/patologia , Toxidermias/fisiopatologia , Hipersensibilidade a Drogas/etiologia , Exantema/induzido quimicamente , Feminino , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Pele/citologia , Pele/efeitos dos fármacos , Pele/patologia
20.
Lung Cancer ; 33(2-3): 229-39, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11551418

RESUMO

Prognosis of lung cancer is related to stage of disease at time of diagnosis. In this study we examine alterations of pathways governing the cell cycle, in particular pRb-cyclinD1-p16 alpha and p53-p14ARF, in a series of NSCLC (n=92) at different stages at diagnosis. Using immunohistochemistry, we assessed the expression of the retinoblastoma protein (pRb), cyclin D1, p16 alpha, p53 and p14ARF. Tumours in stage I-IIIA (resectable) were more likely to have alterations in the pRb-cyclinD1-p16 alpha pathway than tumours in advanced stage (IIIB-IV) (90% versus 63%, P=0.002). pRb and p14ARF were more frequently downregulated in resectable tumours (P< or =0.03), and cyclin D1, p16 alpha, and p53 were altered at a similar frequency in resectable and advanced tumours. In 12 patients, metastatic sites (5 lymph node, 3 bone, 2 brain and 2 gastrointestinal metastases) were available for comparison with the primary tumour: 19 altered protein expressions were found to be concordant, six additional alterations (in 4 patients) were found in the metastases only, especially in lymph node metastases (3 patients). Compared with normal protein expression, both pathway alterations were associated with a longer survival (P=0.02). In a multivariate analysis (Cox regression) this difference was not maintained after adjustment for age, stage and tumour differentiation. Cyclin D1 was the sole protein with independent prognostic value in resectable tumours: the relative risk of local relapse was 4.7 in tumours without cyclin D1 overexpression (P=0.02, Cox regression analysis). No protein studied had a predictive significance for response after chemotherapy in non-resectable tumours. These results demonstrate a strong correlation between stage and pathway alterations, cell cycle regulators being less likely altered in advanced NSCLC. Tumours with defects in these control pathways tend therefore to remain localised and to metastasize at a later phase in tumour development. This finding might be an explanation for distinct biological behaviour (e.g. chemotherapy response) of resectable versus advanced disease.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Neoplasias Pulmonares/metabolismo , Idoso , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Carcinoma Pulmonar de Células não Pequenas/patologia , Ciclo Celular , Núcleo Celular/metabolismo , Ciclina D1/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/metabolismo , Feminino , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Proteínas/metabolismo , Proteína do Retinoblastoma/metabolismo , Taxa de Sobrevida , Proteína Supressora de Tumor p14ARF , Proteína Supressora de Tumor p53/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA