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1.
Ig Sanita Pubbl ; 80(6): 676-692, 2021.
Artigo em Italiano | MEDLINE | ID: mdl-35119055

RESUMO

While the world's economies avoid the COVID-19 pandemic blockade, there is an urgent need for technologies aimed at reducing the transmission of COVID-19 in confined spaces such as hospital environments. Although the cleaning and disinfection procedures now have rather complex and sophisticated weapons, they do not seem to be sufficient to continuously maintain low levels of environmental microbiological contamination. This result can now be achieved through the cross-use, in space and time, of improved, more efficient and effective technologies. This result can now be achieved through the cross-use, in space and time, of improved technologies. This work highlights the possibility of crossing and cooperation of different disinfection techniques, such as to keep the microbial and viral load low over time.


Assuntos
COVID-19 , Infecção Hospitalar , Infecção Hospitalar/prevenção & controle , Desinfecção , Hospitais , Humanos , Pandemias , SARS-CoV-2
4.
Blood Cancer J ; 6(11): e493, 2016 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-27813534

RESUMO

We retrospectively studied 181 patients with polycythaemia vera (n=67), essential thrombocythaemia (n=67) or primary myelofibrosis (n=47), who presented a first episode of splanchnic vein thrombosis (SVT). Budd-Chiari syndrome (BCS) and portal vein thrombosis were diagnosed in 31 (17.1%) and 109 (60.3%) patients, respectively; isolated thrombosis of the mesenteric or splenic veins was detected in 18 and 23 cases, respectively. After this index event, the patients were followed for 735 patient years (pt-years) and experienced 31 recurrences corresponding to an incidence rate of 4.2 per 100 pt-years. Factors associated with a significantly higher risk of recurrence were BCS (hazard ratio (HR): 3.03), history of previous thrombosis (HR: 3.62), splenomegaly (HR: 2.66) and leukocytosis (HR: 2.8). Vitamin K-antagonists (VKA) were prescribed in 85% of patients and the recurrence rate was 3.9 per 100 pt-years, whereas in the small fraction (15%) not receiving VKA more recurrences (7.2 per 100 pt-years) were reported. Intracranial and extracranial major bleeding was recorded mainly in patients on VKA and the corresponding rate was 2.0 per 100 pt-years. In conclusion, despite anticoagulation treatment, the recurrence rate after SVT in myeloproliferative neoplasms is high and suggests the exploration of new avenues of secondary prophylaxis with new antithrombotic drugs and JAK-2 inhibitors.


Assuntos
Síndrome de Budd-Chiari/fisiopatologia , Policitemia Vera/fisiopatologia , Mielofibrose Primária/fisiopatologia , Trombocitemia Essencial/fisiopatologia , Trombose Venosa/fisiopatologia , Adulto , Idoso , Síndrome de Budd-Chiari/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Policitemia Vera/complicações , Veia Porta/fisiopatologia , Mielofibrose Primária/complicações , Modelos de Riscos Proporcionais , Recidiva , Estudos Retrospectivos , Fatores de Risco , Trombocitemia Essencial/complicações , Trombose Venosa/etiologia
5.
Neuropathol Appl Neurobiol ; 42(2): 137-52, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26111612

RESUMO

AIMS: The aggregation of Huntingtin (HTT) protein and of its moiety encoded by its Exon1 (HTTExon1) into fibrillar structures inside neurons is the molecular hallmark of Huntington's disease. Prion-like transmission of these aggregates between cells has been demonstrated. The cell-to-cell transmission mechanisms of these protein aggregates and the susceptibility of different kinds of neuronal cells to these toxic assemblies still need assessment. METHODS: Here, we documented the binding to and internalization by differentiated and undifferentiated neuroblastoma cells of exogenous fibrillar HTTExon1 and polyglutamine (polyQ) polypeptides containing the same number of glutamines. We assessed the contribution of endocytosis to fibrillar HTTExon1 uptake, their intracellular localization and fate. RESULTS: We observed that undifferentiated neuroblastoma cells were more susceptible to fibrillar HTTExon1 and polyQ than their differentiated counterparts. Furthermore, we demonstrated that exogenous HTTExon1 aggregates are mainly taken up by endocytosis and directed to lysosomal compartments in both mitotic and quiescent cells. CONCLUSIONS: These data suggest that the rates of endocytic processes that differ in mitotic and quiescent cells strongly impact the uptake of exogenous HTTExon1 and polyQ fibrils. This may be either the consequence of distinct metabolisms or distributions of specific protein partners for amyloid-like assemblies at the surface of highly dividing versus quiescent cells. Our results highlight the importance of endocytic processes in the internalization of exogenous HTTExon1 fibrils and suggest that a proportion of those assemblies reach the cytosol where they can amplify by recruiting the endogenous protein after escaping, by yet an unknown process, from the endo-lysosomal compartments.


Assuntos
Proteína Huntingtina/metabolismo , Doença de Huntington/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Agregação Patológica de Proteínas/metabolismo , Diferenciação Celular , Linhagem Celular Tumoral , Endocitose/fisiologia , Éxons , Humanos , Doença de Huntington/patologia , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Mitose , Neuroblastoma , Fragmentos de Peptídeos/metabolismo , Peptídeos/metabolismo , Agregação Patológica de Proteínas/patologia , Transfecção
6.
Forensic Sci Int ; 244: 179-85, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25259940

RESUMO

The response to wounds until healing requires the activity of many cell types coordinate in space and time, so that the types of cells in a wound and their localization may be of help to date lesions with respect to death, which would be useful in forensic pathology. Cells reacting to injury include dendritic cells; the early reaction of these cells to skin wounding has not yet been investigated in humans, which was the aim of this study. Samples of wounded and control skin were taken at autopsy and analyzed by affinity histochemistry. Both epidermal and dermal MHC-II+ cells increased transiently in number within the first hour after wounding, then decreased. In the epidermis the increase affected also CD1a+ cells, i.e. well differentiated Langherhans cells, which however increased less, earlier and for a shorter time period than MHC-II+ cells. Dermal MHC-II+ cells became part of a perivascular mononuclear cell infiltrate visible in the subpapillary dermis by 60 min after wounding, which contained also mast cells. The immediately perivascular MHC-II+ cells were DC-SIGN- and CD11c-, while MHC-II+, DC-SIGN+, CD11c+ dendritic cells were predominantly located at the periphery of infiltrates and some were near the epidermis. Mast cells underwent degranulation, besides increase in number, in the first hours after wounding. The results suggest that skin dendritic cells, including Langerhans cells, participate to the early response to wounding in concert with mast cells, and that subpapillary blood vessels are primary sites of cell infiltration during that response in humans. The results show that the ratio between CD1a positive and MHC-II positive cells in the epidermis, the degranulation index of mast cells and the relative volume of MHC-II positive cells in the dermis can be added to the tools useful to distinguish vital from post mortem lesions and, the first two of them, to estimate the interval between a lesion and death.


Assuntos
Células de Langerhans/citologia , Células de Langerhans/metabolismo , Pele/citologia , Pele/lesões , Cicatrização , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos CD1/metabolismo , Contagem de Células , Criança , Pré-Escolar , Feminino , Patologia Legal , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Mastócitos/citologia , Pessoa de Meia-Idade , Mudanças Depois da Morte , Fatores de Tempo , Adulto Jovem
7.
Leukemia ; 28(9): 1811-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24618731

RESUMO

Mutations in the gene calreticulin (CALR) occur in the majority of JAK2- and MPL-unmutated patients with essential thrombocythemia (ET) and primary myelofibrosis (PMF); identifying CALR mutations contributes to the diagnostic pathway of ET and PMF. CALR mutations are heterogeneous spanning over the exon 9, but all result in a novel common protein C terminus. We developed a polyclonal antibody against a 17-amino-acid peptide derived from mutated calreticulin that was used for immunostaining of bone marrow biopsies. We show that this antibody specifically recognized patients harboring different types of CALR mutation with no staining in healthy controls and JAK2- or MPL-mutated ET and PMF. The labeling was mostly localized in megakaryocytes, whereas myeloid and erythroid cells showed faint staining, suggesting a preferential expression of calreticulin in megakaryocytes. Megakaryocytic-restricted expression of calreticulin was also demonstrated using an antibody against wild-type calreticulin and by measuring the levels of calreticulin RNA by gene expression analysis. Immunostaining using an antibody specific for mutated calreticulin may become a rapid, simple and cost-effective method for identifying CALR-mutated patients complementing molecular analysis; furthermore, the labeling pattern supports the preferential expansion of megakaryocytic cell lineage as a result of CALR mutation in an immature hematopoietic stem cell.


Assuntos
Calreticulina/genética , Mutação , Transtornos Mieloproliferativos/genética , Calreticulina/análise , Calreticulina/imunologia , Linhagem da Célula , Humanos , Imuno-Histoquímica , Janus Quinase 2/genética , Transtornos Mieloproliferativos/diagnóstico , Transtornos Mieloproliferativos/etiologia , Receptores de Trombopoetina/genética
8.
Leukemia ; 28(5): 1052-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24150215

RESUMO

With the intent of dissecting the molecular complexity of Philadelphia-negative myeloproliferative neoplasms (MPN), we designed a target enrichment panel to explore, using next-generation sequencing (NGS), the mutational status of an extensive list of 2000 cancer-associated genes and microRNAs. The genomic DNA of granulocytes and in vitro-expanded CD3+T-lymphocytes, as a germline control, was target-enriched and sequenced in a learning cohort of 20 MPN patients using Roche 454 technology. We identified 141 genuine somatic mutations, most of which were not previously described. To test the frequency of the identified variants, a larger validation cohort of 189 MPN patients was additionally screened for these mutations using Ion Torrent AmpliSeq NGS. Excluding the genes already described in MPN, for 8 genes (SCRIB, MIR662, BARD1, TCF12, FAT4, DAP3, POLG and NRAS), we demonstrated a mutation frequency between 3 and 8%. We also found that mutations at codon 12 of NRAS (NRASG12V and NRASG12D) were significantly associated, for primary myelofibrosis (PMF), with highest dynamic international prognostic scoring system (DIPSS)-plus score categories. This association was then confirmed in 66 additional PMF patients composing a final dataset of 168 PMF showing a NRAS mutation frequency of 4.7%, which was associated with a worse outcome, as defined by the DIPSS plus score.


Assuntos
Exoma , Mutação em Linhagem Germinativa , Transtornos Mieloproliferativos/genética , Neoplasias/genética , Estudos de Coortes , Humanos
9.
Leukemia ; 27(9): 1874-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23739289

RESUMO

Under the auspices of an International Working Group, seven centers submitted diagnostic and follow-up information on 1545 patients with World Health Organization-defined polycythemia vera (PV). At diagnosis, median age was 61 years (51% females); thrombocytosis and venous thrombosis were more frequent in women and arterial thrombosis and abnormal karyotype in men. Considering patients from the center with the most mature follow-up information (n=337 with 44% of patients followed to death), median survival (14.1 years) was significantly worse than that of the age- and sex-matched US population (P<0.001). In multivariable analysis, survival for the entire study cohort (n=1545) was adversely affected by older age, leukocytosis, venous thrombosis and abnormal karyotype; a prognostic model that included the first three parameters delineated risk groups with median survivals of 10.9-27.8 years (hazard ratio (HR), 10.7; 95% confidence interval (CI): 7.7-15.0). Pruritus was identified as a favorable risk factor for survival. Cumulative hazard of leukemic transformation, with death as a competing risk, was 2.3% at 10 years and 5.5% at 15 years; risk factors included older age, abnormal karyotype and leukocytes ≥15 × 10(9)/l. Leukemic transformation was associated with treatment exposure to pipobroman or P32/chlorambucil. We found no association between leukemic transformation and hydroxyurea or busulfan use.


Assuntos
Policitemia Vera/diagnóstico , Policitemia Vera/mortalidade , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Transformação Celular Neoplásica , Estudos de Coortes , Progressão da Doença , Feminino , Humanos , Incidência , Leucemia/epidemiologia , Masculino , Pessoa de Meia-Idade , Policitemia Vera/terapia , Prognóstico , Curva ROC , Adulto Jovem
10.
Leukemia ; 27(9): 1861-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23619563

RESUMO

Patient outcome in primary myelofibrosis (PMF) is significantly influenced by karyotype. We studied 879 PMF patients to determine the individual and combinatorial prognostic relevance of somatic mutations. Analysis was performed in 483 European patients and the seminal observations were validated in 396 Mayo Clinic patients. Samples from the European cohort, collected at time of diagnosis, were analyzed for mutations in ASXL1, SRSF2, EZH2, TET2, DNMT3A, CBL, IDH1, IDH2, MPL and JAK2. Of these, ASXL1, SRSF2 and EZH2 mutations inter-independently predicted shortened survival. However, only ASXL1 mutations (HR: 2.02; P<0.001) remained significant in the context of the International Prognostic Scoring System (IPSS). These observations were validated in the Mayo Clinic cohort where mutation and survival analyses were performed from time of referral. ASXL1, SRSF2 and EZH2 mutations were independently associated with poor survival, but only ASXL1 mutations held their prognostic relevance (HR: 1.4; P=0.04) independent of the Dynamic IPSS (DIPSS)-plus model, which incorporates cytogenetic risk. In the European cohort, leukemia-free survival was negatively affected by IDH1/2, SRSF2 and ASXL1 mutations and in the Mayo cohort by IDH1 and SRSF2 mutations. Mutational profiling for ASXL1, EZH2, SRSF2 and IDH identifies PMF patients who are at risk for premature death or leukemic transformation.


Assuntos
Mutação , Mielofibrose Primária/genética , Mielofibrose Primária/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise por Conglomerados , Estudos de Coortes , Feminino , Seguimentos , Perfilação da Expressão Gênica , Humanos , Isocitrato Desidrogenase/genética , Masculino , Pessoa de Meia-Idade , Taxa de Mutação , Proteínas Nucleares/genética , Mielofibrose Primária/diagnóstico , Prognóstico , Proteínas Repressoras/genética , Ribonucleoproteínas/genética , Fatores de Processamento de Serina-Arginina , Adulto Jovem
11.
Minerva Stomatol ; 61(11-12): 477-90, 2012.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-23207673

RESUMO

AIM: While deproteinized bovine bone and bovine membranes have been well studied and can yield good results when used to treat bone defects and peri-implant dehiscences, enzymatically deantigenated equine bone and equine membranes have emerged as possible alternative biomaterials. The objective of this study was the clinical and histological assessment of such materials: equine bone granules, an equine collagen membrane and an equine pericardium membrane. METHODS: Enzymatically deantigenated equine bone and an equine collagen membrane were used to restore a bone defect caused by the removal of a bone cyst in the upper anterior maxilla. After 4.5 months, an implant was placed and a bone core sample was obtained from the grafted site. Implants threads, though, were exposed. This defect was grafted with a mixture of autogenous and equine bone and covered with an equine pericardium membrane. RESULTS: Four months after implant placement the peri-implant bone levels were maintained. A prosthesis was delivered three months later providing functional and esthetic rehabilitation. Also four-year follow-up controls showed implant success. Histological analysis of the bone core revealed that the graft material had undergone remodelling, and a fair amount of newly formed vital bone was present at the time of sample collection. CONCLUSION: The deantigenated equine bone is biocompatible and undergoes osteoclastic remodelling. Both the equine collagen and pericardium membrane acted as effective barriers for guided bone regeneration.


Assuntos
Transplante Ósseo , Cisto Radicular/cirurgia , Animais , Feminino , Cavalos , Humanos , Membranas/transplante , Pessoa de Meia-Idade , Resultado do Tratamento
13.
Leukemia ; 24(7): 1302-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20508616

RESUMO

In a multi-institutional collaborative project, 1473 patients with myeloproliferative neoplasms (MPN) were screened for isocitrate dehydrogenase 1 (IDH1)/IDH2 mutations: 594 essential thrombocythemia (ET), 421 polycythemia vera (PV), 312 primary myelofibrosis (PMF), 95 post-PV/ET MF and 51 blast-phase MPN. A total of 38 IDH mutations (18 IDH1-R132, 19 IDH2-R140 and 1 IDH2-R172) were detected: 5 (0.8%) ET, 8 (1.9%) PV, 13 (4.2%) PMF, 1 (1%) post-PV/ET MF and 11 (21.6%) blast-phase MPN (P<0.01). Mutant IDH was documented in the presence or absence of JAK2, MPL and TET2 mutations, with similar mutational frequencies. However, IDH-mutated patients were more likely to be nullizygous for JAK2 46/1 haplotype, especially in PMF (P=0.04), and less likely to display complex karyotype, in blast-phase disease (P<0.01). In chronic-phase PMF, JAK2 46/1 haplotype nullizygosity (P<0.01; hazard ratio (HR) 2.9, 95% confidence interval (CI) 1.7-5.2), but not IDH mutational status (P=0.55; HR 1.3, 95% CI 0.5-3.4), had an adverse effect on survival. This was confirmed by multivariable analysis. In contrast, in both blast-phase PMF (P=0.04) and blast-phase MPN (P=0.01), the presence of an IDH mutation predicted worse survival. The current study clarifies disease- and stage-specific IDH mutation incidence and prognostic relevance in MPN and provides additional evidence for the biological effect of distinct JAK2 haplotypes.


Assuntos
Isocitrato Desidrogenase/genética , Mutação/genética , Policitemia Vera/genética , Mielofibrose Primária/genética , Trombocitemia Essencial/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Crise Blástica , Estudos de Coortes , Feminino , Humanos , Janus Quinase 2/genética , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Prognóstico , Receptores de Trombopoetina/genética , Adulto Jovem
14.
Int Angiol ; 27(5): 419-25, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18974706

RESUMO

AIM: Multifocal atherosclerotic disease or multifocal ischemic pathology (MAD) is an issue gaining a lot of attention by clinicians in recent years, due to its high impact on the morbidity and mortality of vascular patients. The coexistence of coronary artery disease (CAD), peripheral arterial disease (PAD) and carotid disease (CS) is being investigated in this study. METHODS: The study included 556 consecutive inpatients who were admitted to the Nicosia General Hospital in Cyprus for carotid endarterectomy, peripheral arterial reconstruction or coronary artery bypass. All patients were subjected to color duplex examination of the carotid vessels and to lower extremity Doppler study. Cardiac risk screening was performed on patients with PAD and CS. Comorbidity was evaluated by using the Cumulative Illness Rating Scale (CIRS). RESULTS: The prevalence of MAD in atherosclerotic patients was found very high (60.3%). The most frequent comorbidity was the coexistence of PAD and CAD (41.8%). The comorbidity burden of MAD patients, in comparison to that of patients with unifocal atherosclerotic disease, was evaluated to conclude that the burden in the first group (MAD) is significantly higher, not only in relation to the number of clinically relevant diseases that co-exist, but also to the severity of these diseases. Furthermore, functional status is negatively affected by the existence of multifocal ischemic pathology. CONCLUSION: The high prevalence of MAD suggests the necessity of developing a systematic screening approach in the everyday practice. Apart from cardiovascular problems, other diseases affect the clinical situation of these patients. Therefore, it is important to investigate these problems pre- and postoperatively.


Assuntos
Aterosclerose/epidemiologia , Doenças das Artérias Carótidas/complicações , Doença da Artéria Coronariana/complicações , Doenças Vasculares Periféricas/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/diagnóstico , Doenças das Artérias Carótidas/diagnóstico , Doenças das Artérias Carótidas/cirurgia , Estudos de Coortes , Ponte de Artéria Coronária , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/cirurgia , Chipre , Endarterectomia das Carótidas , Feminino , Nível de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/diagnóstico , Doenças Vasculares Periféricas/cirurgia , Prevalência , Índice de Gravidade de Doença
15.
Histol Histopathol ; 23(1): 19-32, 2008 01.
Artigo em Inglês | MEDLINE | ID: mdl-17952854

RESUMO

We had previously shown that microscopically detectable infiltration of dendritic cells and expression of Hsp47 in tissue lysates occur during repair upon experimental arterial injury. We have further analysed here the cell types involved in the repair process by histology, electron microscopy and immunofluorescence. Rat carotid arteries were subjected to brief crushing and full thickness incision and were analysed up to 21 d thereafter. Adhesion and activation of platelets occurred 3 h after surgery. A neointima had formed 7 d after surgery, where immature cells entered from the lumen and gave rise to cells rich in organelles of the secretory pathway and endowed with bundles of phalloidin-binding microfilaments. Alpha smooth muscle-positive, secretory and contractile smooth muscle cells were found in the neointima 14 and 21 d after injury. Seven to 21 d after surgery, endothelial cells appeared immature and the newly formed tissue contained MHC-II positive, CD43 positive dendritic cells which clustered with lymphocytes, a few macrophages containing apoptotic remnants and cells labelled for Hsp47. Thin elastic fibrils appeared in the neointima 21 d after injury. The results suggest that the response to acute arterial incision injury is mediated by blood borne cells which differentiate along multiple pathways; the process evolves without reaching stabilization within the observed time lapse; the secretion of extracellular matrix is marked by the expression of Hsp47; and the constant presence of dendritic cells clustered with lymphocytes makes these cells candidate to a pivotal role in the tissue response to injury.


Assuntos
Lesões das Artérias Carótidas/patologia , Células Dendríticas/citologia , Endotélio Vascular/citologia , Músculo Liso Vascular/citologia , Cicatrização/fisiologia , Animais , Células Sanguíneas/citologia , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Proteínas de Choque Térmico HSP47/metabolismo , Leucossialina/metabolismo , Linfócitos/citologia , Masculino , Ratos , Ratos Endogâmicos WKY , Túnica Íntima/patologia
16.
Pathobiology ; 71(2): 59-69, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14707440

RESUMO

OBJECTIVES: Intratracheal endotoxin in rats causes acute lung injury. Here we have addressed the cellular physiopathology of lung recovery from that injury. METHODS: The lungs of 5 untreated rats and rats treated with intratracheal endotoxin from 2, 3, 5, 8 (5 rats each) and 15 days (2 rats) were studied by light and electron microscopy and immunohistochemistry. RESULTS: In the acute phase there was a reduction in the aerated spaces (p < 0.01); diffuse infiltration of granulocytes and macrophages; hyperplasia of type-II pneumocytes, and hypertrophy of interstitial cells. Aerated spaces improved during recovery. In the early recovery phase (3-8 days) the compartmentalization of infiltrating cells varied significantly (p < 0.01): macrophages remained widespread while neutrophils were inside blood vessels. Many pneumocytes were intermediate between type-I and type-II cells. In the late recovery phase (15 days) the infiltrate disappeared; myofibroblasts were significantly more than previously (p < 0.01) and extracellular matrix was abundant; type-II pneumocytes contained non-lamellated lipid inclusions. CONCLUSIONS: Macrophages play a pivotal role in the damage-repair processes of the lung following endotoxin injury, leading to an increase in extracellular matrix, differentiation of myofibroblasts and altered secretion of surfactant by newly differentiated type-II pneumocytes.


Assuntos
Endotoxinas/toxicidade , Pulmão/efeitos dos fármacos , Pulmão/patologia , Síndrome do Desconforto Respiratório/patologia , Síndrome do Desconforto Respiratório/fisiopatologia , Animais , Doença Crônica , Modelos Animais de Doenças , Células Epiteliais/patologia , Matriz Extracelular/patologia , Fibroblastos/patologia , Granulócitos/imunologia , Imuno-Histoquímica , Pulmão/ultraestrutura , Microscopia Eletrônica , Surfactantes Pulmonares/metabolismo , Ratos , Síndrome do Desconforto Respiratório/imunologia
17.
Ann N Y Acad Sci ; 1030: 62-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15659781

RESUMO

Receptors of the TNFR superfamily possess abundant thiols in their extracellular domains, which makes them susceptible to redox modulation by prooxidant agents and processes. Previous studies from our laboratory have documented that membrane gamma-glutamyltransferase (GGT) activity can originate reactive oxygen species in the extracellular milieu, during the GGT-mediated metabolism of extracellular glutathione. The present study was aimed thus to verify a possible redox-modulating effect of GGT activity on TNFR1 receptors. The thiol-specific probe maleimide-polyethylene glycol was used to selectively label the reduced thiol groups in proteins of cell lysates; fractions corresponding to TNFR1 were then identified by immunoblot. In human melanoma Me665/2 cells, expressing varying GGT levels, at least five distinct forms of TNFR1 have been thus identified. The more oxidized forms appear to be prevalent in the 2/60 clone, expressing higher GGT levels, as compared to clone 2/21. Stimulation of GGT activity in the latter induced an increase of the oxidized TNFR1 forms. It is conceivable that different redox states of TNFR1 may correspond to different binding affinity and/or changes in the transducing function of the receptor. As GGT is frequently expressed by malignant tumors, the described phenomena might concur to alter the sensitivity of cancer cells to agents targeted on activation of TNF-alpha-dependent signaling pathways.


Assuntos
Melanoma/metabolismo , Estresse Oxidativo , Receptores Tipo I de Fatores de Necrose Tumoral/biossíntese , Linhagem Celular Tumoral , Humanos , Melanoma/patologia , Oxirredução , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo
18.
Mol Psychiatry ; 7(1): 86-9, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11803451

RESUMO

There is significant evidence for genetic factors in the susceptibility to anorexia nervosa (AN). Previously genetic variation in the estrogen receptor 2 gene (ESR2) has been studied, however no strong evidence of association with AN has been found. In the present study variation in the estrogen receptor 1 (ESR1) and ESR2 genes was examined. Estrogen receptors have been localised to areas of the brain involved in behaviour and regulation of food intake. The anorexic effects of estrogen are accentuated by stress and thus it is postulated that variation in the estrogen receptors may contribute to the genetic susceptibility to AN in females. A cohort of 170 female, Caucasian AN sufferers and 152 female controls were typed for dinucleotide repeat polymorphisms in both ESR1 and ESR2 and two further SNPs at each locus. Variation at ESR1 was not associated with AN. However an association was found at the ESR2 locus with the heterozygous genotype of the G1082A polymorphism and AN but not with any of the other ESR2 polymorphisms analysed. Analysis of haplotypes at ESR1 and ESR2 showed no significant evidence of association with AN suggesting that the variability in ESR2 alone may contribute to the genetic susceptibility to AN.


Assuntos
Anorexia Nervosa/genética , Repetições de Dinucleotídeos , Comportamento Alimentar/fisiologia , Polimorfismo de Nucleotídeo Único , Receptores de Estrogênio/genética , Adolescente , Anorexia Nervosa/epidemiologia , Estudos de Coortes , Inglaterra/epidemiologia , Receptor alfa de Estrogênio , Receptor beta de Estrogênio , Éxons/genética , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo Genético , Receptores de Estrogênio/fisiologia , População Branca/genética
19.
Eur J Histochem ; 46(4): 365-75, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12597622

RESUMO

Periodate-lysine-paraformaldehyde (PLP) has been proposed as a fixative for glycoprotein antigens which should stabilize periodate oxidized polysaccharide chains through lysine mediated crosslinks, either directly or by the intermediation of formaldehyde. In spite of premises and attempts reported in the literature, this fixative has never become popular for the study of membrane antigens of immune system cells, which leads to doubts on its real efficacy. We have addressed this issue in biopsies of human skin and found that PLP followed by cryoprotection with 30% sucrose and cryosectioning, or PLP fixation of isolated epidermal sheets, consistently provided for good preservation of morphology and intense labeling of major histocompatibility complex class II molecules, CD 1 a, CD4, CD8, E-cadherin, cytokeratins in general, cytokeratin-18 in particular, and bromodeoxyuridine, incorporated by cycling cells in vitro, and for the demonstration of tyrosinase enzyme activity. PLP-fixed, osmicated and epon-embedded epidermal sheets proved as good as sheets fixed with a mixture of formaldehyde and glutaraldehyde for electron microscopic morphological analysis. Also, these sheets were amenable to immunoperoxidase staining of Langerhans cell membrane antigen CD1a and keratinocyte membrane antigen E-cadherin before being osmicated and prepared for electron microscopy. In a parallel paper, we had also shown that oral mucosa biopsies fixed in PLP showed good morphology and immunolabeling of CD54, CD80, CD83 and CD86. Therefore, we conclude that PLP can be proposed as a multi-task fixative for light and electron microscopic analysis of membrane, cytoplasmic and nuclear antigens of immune system cells and keratinocytes.


Assuntos
Antígenos/química , Fixadores/química , Formaldeído/química , Lisina/química , Ácido Periódico/química , Pele/patologia , Fixação de Tecidos/métodos , Acetona , Biópsia , Ciclo Celular , Humanos , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Indicadores e Reagentes , Queratinócitos/química , Queratinócitos/ultraestrutura , Microscopia Eletrônica , Microscopia Imunoeletrônica , Monofenol Mono-Oxigenase/metabolismo , Pele/citologia
20.
Ital J Anat Embryol ; 106(1): 47-69, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11410998

RESUMO

Langerhans cells are the dendritic cells typical of stratified squamous epithelia and enjoy an intermediate state of differentiation as dendritic cells, since they are very efficient in uptaking and processing antigens but poor in presenting them to lymphocytes. These cells, and other dendritic cells as well, differentiate from bone marrow precursors, with circulating monocytes as intermediates. Langerhans cells leave the epidermis upon loading with antigen and further differentiate into mature dendritic cells while moving to peripheral lymphoid organs, where they elicit primary immune responses. The signals regulating differentiation of precursors into Langerhans cells and of this latter cells into mature dendritic cells have been unraveled thanks to in vitro studies and include a wide range of cytokines, some of which can actively inhibit this process. Also pro-B cells and thymic precursors can give raise in vitro to mature dendritic cells, but apparently not to Langerhans cells. Keratinocytes, the principal cell type of epidermis and mucosal stratified squamous epithelia, can provide for a wide range of cytokines influencing the differentiation of cells of dendritic lineage, in particular Langerhans cells. These cytokines include GM-CSF and TNF-alpha, that may be relevant also for the maintenance of the differentiated state of Langerhans cells within epidermis. Cell to cell contacts mediated by E-cadherin may also contribute signals from keratinocytes to differentiating Langerhans cells. The epidermis and mucosal squamous epithelia host other cell types, besides keratinocytes, and nerve fibers, that all can contribute signals to differentiating Langerhans cells. The differentiation of Langerhans cells within the epithelial microenvironment of skin and mucosae most probably results from the interaction of several players, that play different roles on this scene in different physiological and pathophysiological conditions.


Assuntos
Diferenciação Celular , Células de Langerhans/citologia , Antígenos CD34/análise , Citocinas/metabolismo , Células Epidérmicas , Células Epiteliais/citologia , Humanos , Células de Langerhans/fisiologia , Transdução de Sinais , Células-Tronco/citologia
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