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1.
Am J Transplant ; 17(8): 2215-2220, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28724206

RESUMO

BACKGROUND: Legionnaires' disease, a severe pneumonia, is typically acquired through inhalation of aerosolized water containing Legionella bacteria. Legionella can grow in the complex water systems of buildings, including health care facilities. Effective water management programs could prevent the growth of Legionella in building water systems. METHODS: Using national surveillance data, Legionnaires' disease cases were characterized from the 21 jurisdictions (20 U.S. states and one large metropolitan area) that reported exposure information for ≥90% of 2015 Legionella infections. An assessment of whether cases were health care-associated was completed; definite health care association was defined as hospitalization or long-term care facility residence for the entire 10 days preceding symptom onset, and possible association was defined as any exposure to a health care facility for a portion of the 10 days preceding symptom onset. All other Legionnaires' disease cases were considered unrelated to health care. RESULTS: A total of 2,809 confirmed Legionnaires' disease cases were reported from the 21 jurisdictions, including 85 (3%) definite and 468 (17%) possible health care-associated cases. Among the 21 jurisdictions, 16 (76%) reported 1-21 definite health care-associated cases per jurisdiction. Among definite health care-associated cases, the majority (75, 88%) occurred in persons aged ≥60 years, and exposures occurred at 72 facilities (15 hospitals and 57 long-term care facilities). The case fatality rate was 25% for definite and 10% for possible health care-associated Legionnaires' disease. CONCLUSIONS AND IMPLICATIONS FOR PUBLIC HEALTH PRACTICE: Exposure to Legionella from health care facility water systems can result in Legionnaires' disease. The high case fatality rate of health care-associated Legionnaires' disease highlights the importance of case prevention and response activities, including implementation of effective water management programs and timely case identification.


Assuntos
Infecção Hospitalar/epidemiologia , Instalações de Saúde/estatística & dados numéricos , Doença dos Legionários/epidemiologia , Vigilância da População , Microbiologia da Água , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Surtos de Doenças , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Tempo , Estados Unidos/epidemiologia , Adulto Jovem
2.
Allergy ; 72(4): 562-569, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27588729

RESUMO

BACKGROUND: Overlapping seasons and cross-reactivity, especially to grass pollen profilin, can hamper the diagnosis of birch pollen allergy. To identify the primary sensitizing allergen and the clinical relevance of cross-sensitization, we correlated sensitization profiles with in vitro and in vivo tests, symptom scores, and pollen counts. METHODS: A total of 433 patients with positive skin prick test (SPT) to birch pollen were analyzed regarding IgE to major birch and grass pollen allergens Bet v 1 and Phl p 1/p 5 and the profilins Bet v 2 and Phl p 12. Subgroups were analyzed by basophil activation test (BAT) and CAP-FEIA-based cross- and self-inhibition tests. RESULTS: A total of 349 patients were sensitized to Bet v 1, 44 patients to both Bet v 1 and Bet v 2, and 15 patients to Bet v 2 only. From Bet v 2-sensitized patients, 40 were also sensitized to Phl p 12. Ex vivo, Bet v 2 and Phl p 12 induced dose-dependent activation in basophils of these patients. Cross- and self-inhibition tests with both allergens confirmed cross-reactivity. However, semiquantitative analysis of SPTs demonstrated markedly increased reactivity to grass compared to birch pollen extract in Bet v 2 only sensitized patients. Accordingly, in most of those patients, clinical symptoms precisely correlated with grass pollen counts. CONCLUSION: Identification of the clinically relevant and sensitizing allergen needs correlation of actual pollen counts with clinical symptoms and sensitization status to major allergens. Semiquantitative analysis of SPT or BAT and determining profilin-specific IgE can contribute to making the diagnosis.


Assuntos
Alérgenos/imunologia , Betula/imunologia , Reações Cruzadas/imunologia , Pólen/imunologia , Profilinas/imunologia , Rinite Alérgica Sazonal/diagnóstico , Rinite Alérgica Sazonal/imunologia , Adolescente , Adulto , Especificidade de Anticorpos/imunologia , Basófilos/imunologia , Basófilos/metabolismo , Feminino , Humanos , Imunização , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Contagem de Leucócitos , Masculino , Rinite Alérgica Sazonal/sangue , Testes Cutâneos , Adulto Jovem
3.
Hematology ; 28(1): 2184120, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36867085

RESUMO

We present a family that carries the ß-hemoglobin variant Hb Santa Juana (HBB:c.326A>G, ß 108(G10) Asn>Ser), also known as Hb Serres, in three generations. All affected family members had an anomal hemoglobin fraction as detected by HPLC but normal blood count without evidence of anemia or hemolysis. Oxygen affinity (p50 (O2) = 31.9-40.4 mmHg) was decreased in all probands, compared to 24.9-28.1 mmHg in unaffected individuals. Clinical symptoms likely related to the hemoglobin variant were cyanosis during anaesthesia, while other complaints such as shortness of breath or dizziness were less clearly linked with the hemoglobin variant.


Assuntos
Cianose , Hemoglobinas , Humanos , Cromatografia Líquida de Alta Pressão , Dispneia , Oxigênio
4.
Cytogenet Genome Res ; 136(4): 237-41, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22487875

RESUMO

Tetrasomy 9p is a rare chromosomal syndrome and about 30% of known cases exhibit mosaicism. Approximately 50 of the reported cases with tetrasomy 9p mosaicism show a characteristic facial appearance, growth failure, and developmental delay. However, 3 patients with mosaicism for isochromosome 9p and a normal phenotype have also been reported. We report 2 additional cases of clinically normal young females with tetrasomy 9p mosaicism, one of whom also exhibited X chromosome aneuploidy mosaicism leading to an overall of 6 different cell lines. STR analysis performed on this complex mosaic case indicated that the extra isochromosome was of maternal origin while the X chromosome aneuploidy was of paternal origin, indicating a postzygotic event.


Assuntos
Aneuploidia , Mosaicismo , Adulto , Bandeamento Cromossômico , Cromossomos Humanos Par 9/genética , Cromossomos Humanos X/genética , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Fenótipo , Gravidez , Aberrações dos Cromossomos Sexuais , Adulto Jovem
5.
Respiration ; 84(6): 501-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23037897

RESUMO

BACKGROUND: In recent years experience has been accumulated in percutaneous radiofrequency ablation (RFA) of lung malignancies in nonsurgical patients. OBJECTIVES: In this study, we retrospectively evaluated a simultaneous diagnostic and therapeutic approach including CT-guided biopsy followed immediately by RFA of solitary malignant pulmonary lesions. METHODS: CT-guided transthoracic core needle biopsy of solitary pulmonary lesions suspicious for malignancy was performed and histology was proven based on immediate frozen sections. RFA probes were placed into the pulmonary tumors under CT guidance and the ablation was performed subsequently. The procedure-related morbidity was analyzed. Follow-up included a CT scan and pulmonary function parameters. RESULTS: A total of 33 CT-guided biopsies and subsequent RFA within a single procedure were performed. Morbidity of CT-guided biopsy included pulmonary hemorrhage (24%) and a mild pneumothorax (12%) without need for further interventions. The RFA procedure was not aggravated by the previous biopsy. The rate of pneumothorax requiring chest tube following RFA was 21%. Local tumor control was achieved in 77% with a median follow-up of 12 months. The morbidity of the CT-guided biopsy had no statistical impact on the local recurrence rate. CONCLUSIONS: The simultaneous diagnostic and therapeutic approach including CT-guided biopsy followed immediately by RFA of solitary malignant pulmonary lesions is a safe procedure. The potential of this combined approach is to avoid unnecessary therapies and to perform adequate therapies based on histology. Taking the local control rate into account, this approach should only be performed in those patients who are unable to undergo or who refuse surgery.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Ablação por Cateter/métodos , Neoplasias Pulmonares , Nódulo Pulmonar Solitário , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Ablação por Cateter/efeitos adversos , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Masculino , Pessoa de Meia-Idade , Pneumotórax/etiologia , Estudos Retrospectivos , Nódulo Pulmonar Solitário/patologia , Nódulo Pulmonar Solitário/cirurgia , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X/métodos
6.
Pathologe ; 33(3): 192-204, 2012 May.
Artigo em Alemão | MEDLINE | ID: mdl-22576595

RESUMO

Current findings from the literature on the multifactorial genesis of macroangiopathy of diabetes mellitus (DM) were compiled using the PubMed database. The primary aim was to find an explanation for the morphological, immunohistochemical and molecular characteristics of this form of atherosclerosis. The roles of advanced glycation end products (AGE), defective signal transduction and imbalance of matrix metalloproteinases in the increased progression of atherosclerosis in coronary and cerebral arteries as well as peripheral vascular disease are discussed. The restricted formation of collateral arteries (arteriogenesis) in diabetic patients with postischemic lesions is also a focus of attention. The increased level of prothrombotic factors and the role of diabetic neuropathy in DM are also taken into account. Therapeutic influences of AGE-RAGE (receptor of AGE) interactions on the vascular wall and the effects of endothelial progenitor cells in the repair of diabetic vascular lesions are additionally highlighted.


Assuntos
Angiopatias Diabéticas/patologia , Aterosclerose/patologia , Progressão da Doença , Produtos Finais de Glicação Avançada/fisiologia , Humanos , Metaloproteinases da Matriz/fisiologia , Neovascularização Patológica/patologia , Transdução de Sinais , Células-Tronco/patologia
7.
Arch Gynecol Obstet ; 280(6): 1049-53, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19340439

RESUMO

PURPOSE: We report a rare case of Pallister-Killian syndrome diagnosed prenatally with increased nuchal translucency during screening for trisomy 21. MATERIALS AND METHODS: Echografic and postmortem examination of the fetus, G-banded chromosome and FISH analysis on short- and long-term chorion villous sampling (CVS) culture. RESULTS AND DISCUSSION: Cytogenetic analysis revealed a supernumerary isochromosome 12p after long-term culture whereas a normal cell line was detected in short-term culture only. Sonografic examination in 17-weeks' gestation showed further increase of the NT and the additional presence of brachymelia, diaphragmatic hernia and a marked dextroposition of the heart. Termination of the pregnancy was performed. The cases of PKS karyotypically confirmed on CVS are reviewed, and cytogenetic and sonographic aspects of the prenatal diagnosis of PKS are discussed.


Assuntos
Anormalidades Múltiplas/embriologia , Aberrações Cromossômicas/embriologia , Cromossomos Humanos Par 12/genética , Isocromossomos/genética , Anormalidades Múltiplas/diagnóstico por imagem , Anormalidades Múltiplas/genética , Feto Abortado , Adulto , Evolução Fatal , Feminino , Humanos , Cariotipagem , Medição da Translucência Nucal , Gravidez , Ultrassonografia Pré-Natal
8.
Trends Biochem Sci ; 18(9): 334-8, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7694398

RESUMO

The mechanisms of action of the immunosuppressive drugs cyclosporin A (CsA), FK506 and rapamycin are strikingly conserved from yeast to human T cells. Recent results obtained with yeast corroborate calcineurin as the target of CsA-cyclophilin and FK506-FKBP complexes, and reveal a phosphatidylinositol 3-kinase homologue as the target of the rapamycin-FKBP complex.


Assuntos
Ciclosporina/farmacologia , Imunossupressores/farmacologia , Polienos/farmacologia , Tacrolimo/farmacologia , Isomerases de Aminoácido/metabolismo , Sequência de Aminoácidos , Calcineurina , Proteínas de Ligação a Calmodulina/metabolismo , Proteínas de Transporte/metabolismo , Sequência Consenso , Dados de Sequência Molecular , Peptidilprolil Isomerase , Fosfatidilinositol 3-Quinases , Fosfoproteínas Fosfatases/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sirolimo
9.
Mol Cell Biol ; 13(8): 5010-9, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7687745

RESUMO

The immunosuppressants cyclosporin A, FK506, and rapamycin inhibit growth of unicellular eukaryotic microorganisms and also block activation of T lymphocytes from multicellular eukaryotes. In vitro, these compounds bind and inhibit two different types of peptidyl-prolyl cis-trans isomerases. Cyclosporin A binds cyclophilins, whereas FK506 and rapamycin bind FK506-binding proteins (FKBPs). Cyclophilins and FKBPs are ubiquitous, abundant, and targeted to multiple cellular compartments, and they may fold proteins in vivo. Previously, a 12-kDa cytoplasmic FKBP was shown to be only one of at least two FK506-sensitive targets in the yeast Saccharomyces cerevisiae. We find that a second FK506-sensitive target is required for amino acid import. Amino acid-auxotrophic yeast strains (trp1 his4 leu2) are FK506 sensitive, whereas prototrophic strains (TRP1 his4 leu2, trp1 HIS4 leu2, and trp1 his4 LEU2) are FK506 resistant. Amino acids added exogenously to the growth medium mitigate FK506 toxicity. FK506 induces GCN4 expression, which is normally induced by amino acid starvation. FK506 inhibits transport of tryptophan, histidine, and leucine into yeast cells. Lastly, several genes encoding proteins involved in amino acid import or biosynthesis confer FK506 resistance. These findings demonstrate that FK506 inhibits amino acid import in yeast cells, most likely by inhibiting amino acid transporters. Amino acid transporters are integral membrane proteins which import extracellular amino acids and constitute a protein family sharing 30 to 35% identity, including eight invariant prolines. Thus, the second FK506-sensitive target in yeast cells may be a proline isomerase that plays a role in folding amino acid transporters during transit through the secretory pathway.


Assuntos
Aminoácidos/metabolismo , Proteínas Fúngicas/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Tacrolimo/farmacologia , Sequência de Aminoácidos , Transporte Biológico/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Resistência Microbiana a Medicamentos , Proteínas Fúngicas/química , Genes Fúngicos , Dados de Sequência Molecular , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Proteínas de Ligação a Tacrolimo
10.
Mol Biol Cell ; 5(1): 105-18, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8186460

RESUMO

The Saccharomyces cerevisiae genes TOR1 and TOR2 were originally identified by mutations that confer resistance to the immunosuppressant rapamycin. TOR2 was previously shown to encode an essential 282-kDa phosphatidylinositol kinase (PI kinase) homologue. The TOR1 gene product is also a large (281 kDa) PI kinase homologue, with 67% identity to TOR2. TOR1 is not essential, but a TOR1 TOR2 double disruption uniquely confers a cell cycle (G1) arrest as does exposure to rapamycin; disruption of TOR2 alone is lethal but does not cause a cell cycle arrest. TOR1-TOR2 and TOR2-TOR1 hybrids indicate that carboxy-terminal domains of TOR1 and TOR2 containing a lipid kinase sequence motif are interchangeable and therefore functionally equivalent; the other portions of TOR1 and TOR2 are not interchangeable. The TOR1-1 and TOR2-1 mutations, which confer rapamycin resistance, alter the same potential protein kinase C site in the respective protein's lipid kinase domain. Thus, TOR1 and TOR2 are likely similar but not identical, rapamycin-sensitive PI kinases possibly regulated by phosphorylation. TOR1 and TOR2 may be components of a novel signal transduction pathway controlling progression through G1.


Assuntos
Ciclo Celular/genética , Proteínas Fúngicas/genética , Genes Fúngicos , Fosfatidilinositol 3-Quinases , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae/enzimologia , 1-Fosfatidilinositol 4-Quinase , Sequência de Aminoácidos , Sequência de Bases , Proteínas de Ciclo Celular , Resistência Microbiana a Medicamentos/genética , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/química , Dados de Sequência Molecular , Fosfotransferases (Aceptor do Grupo Álcool)/antagonistas & inibidores , Fosfotransferases (Aceptor do Grupo Álcool)/química , Polienos/farmacologia , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Sirolimo
11.
Blood Cancer J ; 7(2): e523, 2017 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-28157215

RESUMO

In the search for genes that define critical steps of relapse in pediatric T-cell acute lymphoblastic leukemia (T-ALL) and can serve as prognostic markers, we performed targeted sequencing of 313 leukemia-related genes in 214 patients: 67 samples collected at the time of relapse and 147 at initial diagnosis. As relapse-specific genetic events, we identified activating mutations in NT5C2 (P=0.0001, Fisher's exact test), inactivation of TP53 (P=0.0007, Fisher's exact test) and duplication of chr17:q11.2-24.3 (P=0.0068, Fisher's exact test) in 32/67 of T-ALL relapse samples. Alterations of TP53 were frequently homozygous events, which significantly correlated with higher rates of copy number alterations in other genes compared with wild-type TP53 (P=0.0004, Mann-Whitney's test). We subsequently focused on mutations with prognostic impact and identified genes governing DNA integrity (TP53, n=8; USP7, n=4; MSH6, n=4), having key roles in the RAS signaling pathway (KRAS, NRAS, n=8), as well as IL7R (n=4) and CNOT3 (n=4) to be exclusively mutated in fatal relapses. These markers recognize 24/49 patients with a second event. In 17 of these patients with mostly refractory relapse and dire need for efficient treatment, we identified candidate targets for personalized therapy with p53 reactivating compounds, MEK inhibitors or JAK/STAT-inhibitors that may be incorporated in future treatment strategies.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Criança , Pré-Escolar , Intervalo Livre de Doença , Humanos , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Prognóstico , Fatores de Risco
12.
Leukemia ; 31(10): 2048-2056, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28196983

RESUMO

Recent developments in sequencing technologies led to the discovery of a novel form of genomic instability, termed chromothripsis. This catastrophic genomic event, involved in tumorigenesis, is characterized by tens to hundreds of simultaneously acquired locally clustered rearrangements on one chromosome. We hypothesized that leukemias developing in individuals with Ataxia Telangiectasia, who are born with two mutated copies of the ATM gene, an essential guardian of genome stability, would show a higher prevalence of chromothripsis due to the associated defect in DNA double-strand break repair. Using whole-genome sequencing, fluorescence in situ hybridization and RNA sequencing, we characterized the genomic landscape of Acute Lymphoblastic Leukemia (ALL) arising in patients with Ataxia Telangiectasia. We detected a high frequency of chromothriptic events in these tumors, specifically on acrocentric chromosomes, as compared with tumors from individuals with other types of DNA repair syndromes (27 cases total, 10 with Ataxia Telangiectasia). Our data suggest that the genomic landscape of Ataxia Telangiectasia ALL is clearly distinct from that of sporadic ALL. Mechanistically, short telomeres and compromised DNA damage response in cells of Ataxia Telangiectasia patients may be linked with frequent chromothripsis. Furthermore, we show that ATM loss is associated with increased chromothripsis prevalence in additional tumor entities.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/fisiologia , Ataxia Telangiectasia/genética , Proteínas de Neoplasias/fisiologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Ataxia Telangiectasia/complicações , Proteínas Mutadas de Ataxia Telangiectasia/deficiência , Proteínas Mutadas de Ataxia Telangiectasia/genética , Criança , Pré-Escolar , Cromossomos Humanos/ultraestrutura , Cromotripsia , Reparo do DNA/genética , DNA de Neoplasias/genética , Feminino , Genoma Humano , Instabilidade Genômica , Humanos , Hibridização in Situ Fluorescente , Masculino , Mutação , Proteínas de Neoplasias/deficiência , Proteínas de Neoplasias/genética , Neoplasias/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , RNA Neoplásico/genética , Análise de Sequência de DNA , Análise de Sequência de RNA , Encurtamento do Telômero/genética , Transcriptoma
13.
Clin Drug Investig ; 26(3): 143-50, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17163245

RESUMO

OBJECTIVE: The purpose of this study was to assess the efficacy and safety of a new low-dose oral contraceptive containing ethinylestradiol 20microg and drospirenone 3mg (EE 20microg/drsp 3mg). METHODS: This was an open-label, non-comparative, multicentre study conducted at 33 centres in Germany and Switzerland. The combined contraceptive was administered over 26 cycles of treatment, with each cycle consisting of once-daily treatment for 21 consecutive days followed by a 7-day hormone-free interval. RESULTS: A total of 527 women were randomised, of whom 516 (97.9%) started treatment and had at least one study observation. Two pregnancies occurred during 11 165 cycles of treatment, giving a Pearl Index of 0.23 (upper limit of 97.5% CI 0.84). The corresponding 2-year cumulative pregnancy rate was 0.44% (95% CIs 0, 1.05). One of the two pregnancies was attributed to non-compliance with treatment, giving an adjusted Pearl Index of 0.12 (upper limit of 97.5% CI 0.67) over 10 827 compliant cycles. Only three (0.6%) women discontinued treatment because of bleeding problems in this long-term study, suggesting an acceptable bleeding profile. Overall, the study drug was well tolerated and adverse events experienced were typical of hormonal contraceptive use. The majority of women who responded (435 of 501; 86.8%) were satisfied or very satisfied with the study treatment and most (367 of 501; 73.3%) would continue with it if given the choice. CONCLUSION: The EE 20microg/drsp 3 mg combined oral contraceptive is an effective and well tolerated contraceptive with an acceptable bleeding pattern.


Assuntos
Androstenos/administração & dosagem , Anticoncepcionais Orais Combinados/farmacologia , Etinilestradiol/administração & dosagem , Adolescente , Adulto , Androstenos/efeitos adversos , Etinilestradiol/efeitos adversos , Feminino , Humanos , Cooperação do Paciente , Satisfação do Paciente
14.
J Mol Med (Berl) ; 74(1): 35-42, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8834768

RESUMO

Molecular alterations play a key role in the pathogenesis of gastrointestinal cancers. In the present paper we describe relevant molecular alterations in human pancreatic adenocarcinomas. Overexpression of growth factor receptors (EGF receptor, c-erbB2, c-erbB3, TGF beta receptor I-III), growth factors (EGF, TGF alpha, TGF beta-1-3, aFGF, bFGF), adhesion molecules (ICAM-1, ELAM-1) and gene mutations (p53, K-ras, DCC, APC) are present in a significant number of these tumors. These changes stimulate tumor growth and enhance the metastatic behavior of pancreatic cancer cells and thereby may contribute to shorter postoperative survival following tumor resection.


Assuntos
Substâncias de Crescimento/metabolismo , Neoplasias Pancreáticas/metabolismo , Receptores de Fatores de Crescimento/metabolismo , Selectina E/metabolismo , Genes ras/genética , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Ligantes , Mutação , Neoplasias Pancreáticas/genética
15.
J Cereb Blood Flow Metab ; 18(11): 1270-81, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9809517

RESUMO

In this study we show that the aminopeptidase N of cerebral pericytes (pAPN) associated with the blood-brain barrier (BBB) is downregulated in pericytic cell cultures. This observation is in accordance with previous data describing comparable in vitro effects for BBB-specific enzymes of endothelial or pericytic origin, such as gamma-glutamyl transpeptidase or alkaline phosphatase. By polymerase chain reaction and in situ hybridization we were able to determine that the down-regulation of pAPN occurs at the posttranscriptional level. The mRNA of pAPN was found to be constitutively expressed even when the protein is no longer detectable. Culturing the pericytes in an endothelial cell-conditioned medium allowed pAPN to be reexpressed. However, the reexpression effect depended largely on the culturing conditions of the pericytes. Although purified pericytes deprived of endothelial cells did not reveal a reexpression effect, pericytes that were kept in contact with endothelial cells were able to acquire a pAPN-positive phenotype, indicating that endothelial cells constitute an essential requirement for the in vitro reexpression of pAPN. Astrocytes, however, were insufficient in exerting any reexpression effect.


Assuntos
Barreira Hematoencefálica , Encéfalo/enzimologia , Antígenos CD13/genética , Regulação Enzimológica da Expressão Gênica , Microcirculação/fisiologia , Pericitos/enzimologia , Animais , Anticorpos , Anticorpos Monoclonais , Astrócitos/citologia , Astrócitos/fisiologia , Encéfalo/citologia , Antígenos CD13/biossíntese , Células Cultivadas , Córtex Cerebral/irrigação sanguínea , Técnicas de Cocultura , Meios de Cultivo Condicionados , Endotélio Vascular/citologia , Endotélio Vascular/fisiologia , Microcirculação/citologia , Pericitos/citologia , Biossíntese de Proteínas , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Transcrição Gênica
16.
Cell Prolif ; 33(3): 147-66, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10959624

RESUMO

The response kinetics of rat C6 glioma cells to heat shock was investigated by means of flow cytometric DNA measurements and western blot analysis of HSP levels. The results showed that the effects on cell cycle progression are dependent on the cell cycle phase at which heat shock is applied, leading to either G1 or G2/M arrest in randomly proliferating cells. When synchronous cultures were stressed during G0 they were arrested with G1 DNA content and showed prolongation of S and G2 phases after release from the block. In proliferating cells, HSC70 and HSP68 were induced during the recovery and reached maximum levels just before cells were released from the cell cycle blocks. Hyperthermic pretreatment induced thermotolerance both in asynchronous and synchronous cultures as evidenced by the reduced arrest of cell cycle progression after the second heat shock. Thermotolerance development was independent of the cell cycle phase. Pre-treated cells already had high HSP levels and did not further increase the amount of HSP after the second treatment. However, as in unprimed cells, HSP reduction coincided with the release from the cell cycle blocks. These results imply that the cell cycle machinery can be rendered thermotolerant by heat shock pretreatment and supports the assumption that HSP70 family members might be involved in thermotolerance development.


Assuntos
Adaptação Fisiológica , Neoplasias Encefálicas/patologia , Ciclo Celular , Glioma/patologia , Resposta ao Choque Térmico , Animais , Western Blotting , Divisão Celular , Citometria de Fluxo , Proteínas de Choque Térmico HSP70/fisiologia , Ratos , Células Tumorais Cultivadas
17.
FEBS Lett ; 275(1-2): 1-5, 1990 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-2175710

RESUMO

Nuclear proteins are actively and posttranslationally transported across the nuclear envelope. This transport is a highly selective process that can be divided into two steps, receptor-binding followed by translocation through the nuclear envelope. Receptor-binding is mediated by nuclear localization signals that have been identified in many nuclear proteins. Translocation is energy-dependent and occurs through the nuclear pore complex.


Assuntos
Membrana Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Animais , Transporte Biológico Ativo , Compartimento Celular , Dados de Sequência Molecular , Membrana Nuclear/ultraestrutura , Proteínas Nucleares/química , Receptores de Superfície Celular/metabolismo , Sequências Reguladoras de Ácido Nucleico
18.
Mech Ageing Dev ; 4(5-6): 361-9, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1228335

RESUMO

In order to study the physiological regeneration of the endothelium, "Hautchen", preparations of aortic endothelium were produced from 15 rabbits of different ages and studied autoradiographically. By determining the number of 3H-thymidine-labelled cells, the mitotic rate and the total number of cells per 0.12 mm2, we arrived at the following conclusions: (1) The mean generation time of endothelial cells increases with advancing age. The extension of the mean generation time of the endothelial cells, as deduced from the decrease in the 3H-thymidine labelling index and in the mitotic rate, mainly occurs during the first four months of life. (2) Neither between topologically different aortic segments nor between such portions of the aorta as are exposed to different flow-mechanical stresses could any considerable differences with regard to the reproduction rate of their endothelial cells be detected. The raised endothelial turnover in the area of the iliac bifurcation requires further studies.


Assuntos
Envelhecimento , Aorta/fisiologia , Regeneração , Animais , Aorta Abdominal/fisiologia , Aorta Torácica/fisiologia , Endotélio/citologia , Endotélio/metabolismo , Endotélio/fisiologia , Feminino , Masculino , Mitose , Coelhos , Timidina/metabolismo
19.
Mol Biochem Parasitol ; 53(1-2): 53-61, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1380126

RESUMO

A comparative survey was undertaken of the neutral fraction glycolipids from the metacestodes of 3 taeniid species, Taenia crassiceps, Taenia solium and Taenia saginata, to determine their chemical and serological staining patterns on separation by thin-layer chromatography. The orcinol-positive patterns of T. solium and T. saginata metacestodes exhibited a closer superficial resemblance to each other than to T. crassiceps or T. saginata adults. A comparison of component migration properties against standards of known structure indicated the main oligosaccharide chains to be mono-, di-, tri- and tetrasaccharides; however, in T. solium this was extended to at least a heptasaccharide. The multiple banding characteristic of each component is a consequence of lipid moiety heterogeneity. Serologically, the patterns of the 3 taeniid species neutral fraction glycolipids showed virtually the same immunological reactivity towards mouse normal serum, infection serum and a monospecific, polyclonal antibody directed against the trisaccharide component of T. crassiceps. The latter antibody was isolated from mouse infection serum by affinity chromatography on a column of glycolipid-bound octyl-Sepharose CL-4B. Immunochemically, the major common epitope expressed by the neutral fraction glycolipids of the 3 taeniid species is the same or very similar to the glycosphingolipid, neogalatriaosyl ceramide derived from the marine mollusc Turbo cornutus (Gal(beta 1-6) Gal(beta 1-6) Gal(beta 1-1)Cer). Host tissue neutral fraction glycolipids, porcine muscle and bovine muscle, as well as human spleen, were not immunoreactive.


Assuntos
Glicolipídeos/imunologia , Taenia/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Antígenos de Helmintos/química , Sequência de Carboidratos , Cromatografia em Camada Fina , Reações Cruzadas , Epitopos/química , Glicolipídeos/química , Camundongos , Dados de Sequência Molecular , Oligossacarídeos/química , Oligossacarídeos/imunologia , Especificidade da Espécie , Taenia/química , Teníase/imunologia
20.
J Neuroimmunol ; 59(1-2): 41-55, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7797619

RESUMO

The role of cerebral pericytes in blood-brain barrier (BBB) mechanisms is still a matter of controversy. Because acute experimental autoimmune encephalomyelitis (EAE) is characterized by a transient and focal perturbation of the BBB, we have utilized the model of adoptive transfer EAE to correlate the expression of the pericytic aminopeptidase N (pAP N) with the acute functional state of the BBB. We demonstrate that a significant downregulation of microvascular pAP N expression occurs, and the observed perturbation of the enzymatic BBB complement seems to be a sustained effect which persists even after recovery from clinical disease. At the peak of clinical disease, numerous pAP N expressing invasive cells were detected in white matter of the lumbar spinal cord. Through the use of a panel of different immunocytochemical markers these pAP N-immunopositive cells were characterized as ED 1-positive, most likely hematogenous macrophages. Activated resident microglial cells participate in the EAE-induced inflammatory process to only a minor extent.


Assuntos
Barreira Hematoencefálica , Encéfalo/enzimologia , Antígenos CD13/análise , Encefalomielite Autoimune Experimental/enzimologia , Medula Espinal/enzimologia , Doença Aguda , Animais , Feminino , Antígenos de Histocompatibilidade Classe II/análise , Imuno-Histoquímica , Microcirculação/enzimologia , Ratos , Ratos Endogâmicos Lew
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