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1.
Appl Opt ; 56(4): C193-C200, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28158073

RESUMO

Random effects in the repeatability of refractive index and absorption edge position of tantalum pentoxide layers prepared by plasma-ion-assisted electron-beam evaporation, ion beam sputtering, and magnetron sputtering are investigated and quantified. Standard deviations in refractive index between 4*10-4 and 4*10-3 have been obtained. Here, lowest standard deviations in refractive index close to our detection threshold could be achieved by both ion beam sputtering and plasma-ion-assisted deposition. In relation to the corresponding mean values, the standard deviations in band-edge position and refractive index are of similar order.

2.
J Neurol Neurosurg Psychiatry ; 86(9): 965-72, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25300449

RESUMO

BACKGROUND: Two novel antibodies (abs) directed to γ-aminobutyric acid B receptor (GABA(B)R) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) in patients with limbic encephalitis (LE) were first described by the Philadelphia/Barcelona groups and confirmed by the Mayo group. We present a novel series for further clinical and paraclinical refinement. METHODS: Serum and cerebrospinal fluid samples from a diagnostic laboratory were selected if found to be positive for GABA(B)R or AMPAR abs within a broad antineuronal ab panel. Data were retrospectively compiled. RESULTS: In 10 patients, we detected abs to GABA(B)R. Median age was 70 years. Five of them were diagnosed with small cell lung cancer (SCLC). Intrathecal GABA(B)R ab synthesis was found in all six patients with sufficient data available (median ab-index: 76.8). On MRI, we found bilateral mediotemporal and in two cases cortical abnormalities. EEG revealed encephalopathy, partly with epileptiform discharges. Five patients received immunotherapy, two patients tumour treatment and three both therapies. Three patients died, in five patients cognitive functions declined, one patient improved slightly and one patient fully recovered. AMPAR abs were detected in three patients with mnestic disturbances. Median age was 60.7 years. The only female patient was diagnosed with ovarian cancer. None of the patients had intrathecal ab synthesis. MRI findings showed bilateral mediotemporal abnormalities. EEG was normal in all patients. Two of the three immunologically treated patients improved, one patient stabilised on a low level. DISCUSSION: GABA(B)R and AMPAR abs are well associated with LE. GABA(B)R abs lead to severe clinical, neuroradiological and EEG abnormalities with poorer outcome.


Assuntos
Autoanticorpos/sangue , Encefalite Límbica/imunologia , Receptores de AMPA/imunologia , Receptores de GABA-B/imunologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
HNO ; 63(11): 768-72, 2015 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-26507714

RESUMO

BACKGROUND: HPV infections play a major role in the pathogenesis of squamous cell carcinomas of the head and neck. Regarding benign papillomas, the role of HPV is still uncertain. MATERIALS AND METHODS: To clarify this issue, 100 exophytic papillomas of the oral cavity, pharynx and larynx were subjected to histopathological and molecular pathological examination. Excision biopsies were taken from 62 male and 38 female patients with an age range of 18 to 87 years. Biopsies were tested for p16 expression by immunohistochemistry and analyzed for HPV subtypes 6/11 (low-risk), 16/18 and 31/33/53 (high-risk) by chromogenic in situ hybridization. RESULTS: HPV infections were verified molecularly in 34 % of biopsies; in all cases with the low-risk HPV subtypes 6/11. Only one case showed infection with both 6/11 and 31/33/53 subtypes, but not subtype 16/18; whereas expression of p16 was found in 67 %. The rate of positive molecular verification of HPV infection (in situ hybridization) was highest in the laryngeal lesions with 61.1 %, followed by the oral cavity with 52.9 %, and lowest in pharyngeal lesions (21.5 %). Recurrent papillomas were seen in 18 cases (18 %), of which 14 were molecularly positive for HPV (in situ hybridization). A correlation between inflammatory infiltration and HPV infection could be verified in 82 %. CONCLUSION: Our data demonstrate an important role of HPV infection for the development of benign papillomas of the head and neck region. Furthermore, there is a positive correlation between HPV infection and recurrent papillomas. Therefore, a molecular morphological HPV analysis of papillomas could provide important prognostic data.


Assuntos
Neoplasias de Cabeça e Pescoço/epidemiologia , Recidiva Local de Neoplasia/epidemiologia , Papiloma/epidemiologia , Infecções por Papillomavirus/epidemiologia , Lesões Pré-Cancerosas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Causalidade , Comorbidade , Feminino , Alemanha/epidemiologia , Neoplasias de Cabeça e Pescoço/microbiologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/microbiologia , Recidiva Local de Neoplasia/patologia , Papiloma/microbiologia , Papiloma/patologia , Infecções por Papillomavirus/microbiologia , Infecções por Papillomavirus/patologia , Lesões Pré-Cancerosas/microbiologia , Lesões Pré-Cancerosas/patologia , Prevalência , Fatores de Risco , Adulto Jovem
6.
Clin Dev Immunol ; 2012: 595427, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22242037

RESUMO

BACKGROUND: Data on the economic impact of Lyme borreliosis (LB) on European health care systems is scarce. This project focused on the epidemiology and costs for laboratory testing in LB patients in Germany. MATERIALS AND METHODS: We performed a sentinel analysis of epidemiological and medicoeconomic data for 2007 and 2008. Data was provided by a German statutory health insurance (DAK) company covering approx. 6.04 million members. In addition, the quality of diagnostic testing for LB in Germany was studied. RESULTS: In 2007 and 2008, the incident diagnosis LB was coded on average for 15,742 out of 6.04 million insured members (0.26%). 20,986 EIAs and 12,558 immunoblots were ordered annually for these patients. For all insured members in the outpatient sector, a total of 174,820 EIAs and 52,280 immunoblots were reimbursed annually to health care providers (cost: 2,600,850€). For Germany, the overall expected cost is estimated at 51,215,105€. However, proficiency testing data questioned test quality and standardization of diagnostic assays used. CONCLUSION: Findings from this study suggest ongoing issues related to care for LB and may help to improve future LB disease management.


Assuntos
Custos de Cuidados de Saúde , Doença de Lyme/diagnóstico , Doença de Lyme/economia , Borrelia/imunologia , Técnicas de Laboratório Clínico/economia , Técnicas de Laboratório Clínico/normas , Alemanha/epidemiologia , Humanos , Incidência , Seguro Saúde/economia , Doença de Lyme/epidemiologia , Modelos Estatísticos , Pacientes Ambulatoriais , Prevalência , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade
7.
HNO ; 59(5): 503-6, 2011 May.
Artigo em Alemão | MEDLINE | ID: mdl-21279314

RESUMO

We report the rare case of a posttraumatic intraorbital fistula. The patient was referred to our clinic with a suspected complication of acute sinusitis. The patient reported recurrent swelling of the eyelid with a temporal fluctuation during the day. Eyesight was normal. In the presence of acute rhinogenic infection, computer tomography of the paranasal sinuses demonstrated a shadow on the ethmoid bone and ipsilateral maxillary sinus. Clinical investigation and laboratory parameters excluded an infection. A kick to the head by a horse could be documented on patient interview. By means of angio-MRI an arteriovenous fistula of the orbit could be diagnosed.


Assuntos
Fístula Arteriovenosa/diagnóstico , Traumatismos Cranianos Fechados/complicações , Artéria Oftálmica/anormalidades , Artéria Oftálmica/diagnóstico por imagem , Artéria Oftálmica/patologia , Diagnóstico Diferencial , Feminino , Traumatismos Cranianos Fechados/diagnóstico , Humanos , Pessoa de Meia-Idade , Radiografia
8.
HNO ; 57(11): 1209-12, 2009 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-19701617

RESUMO

Infections due to the Mycobacterium tuberculosis of the head and neck region mainly affect the cervical lymph nodes. We report a rare case of paranasal sinus tuberculosis. The patient presented as an emergency with right-sided headache and epiphora. Clinical, radiological and laboratory results yielded a diagnosis of acute exacerbated chronic sinusitis with meningeal affection resulting from transmigration. Histological and molecular investigations confirmed mycobacterial infection of the paranasal sinuses.


Assuntos
Doenças dos Seios Paranasais/diagnóstico , Tuberculose/diagnóstico , Diagnóstico Diferencial , Endoscopia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças dos Seios Paranasais/patologia , Doenças dos Seios Paranasais/cirurgia , Seios Paranasais/patologia , Seios Paranasais/cirurgia , Reação em Cadeia da Polimerase , Tomografia Computadorizada por Raios X , Tuberculose/patologia , Tuberculose/cirurgia
9.
Br J Ophthalmol ; 91(5): 592-5, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17108014

RESUMO

BACKGROUND: Ocular involvement of syphilis still poses a clinical challenge due to the chameleonic behaviour of the disease. As the serodiagnosis has significant limitations, the direct detection of Treponema pallidum (TP) in the vitreous represents a desirable diagnostic tool. METHODS: Real-time polymerase chain reaction (PCR) for the detection of TP was applied in diagnostic vitrectomies of two patients with acute chorioretinitis. Qualitative verification of TP by real-time PCR and melting point analysis according to a modified protocol was ruled out. Patients underwent complete ophthalmological examination with fundus photographs, fluorescein angiography, serological examination, antibiotic treatment and follow-up. RESULTS: In two cases of acute chorioretinitis of unknown origin, real-time PCR of vitreous specimens of both patients provided evidence of TP and was 100% specific. Initial diagnosis of presumed viral retinitis was ruled out by PCR of vitreous specimen. Patients were treated with systemic antibiotics and showed prompt improvement in visual function and resolution of fundus lesions. CONCLUSIONS: With real-time PCR, detection of TP in the vitreous was possible and delivered a sensitive, quick and inexpensive answer to a disease rather difficult to assess. In cases of acute chorioretinitis, the use of PCR-based assays of vitreous specimens in the diagnostic evaluation of patients is advisable. Although syphilitic chorioretinitis is a rare disease, PCR should include search for TP, as diagnostic dilemmas prolong definitive treatment in a sight-threatening disease.


Assuntos
Infecções Oculares Bacterianas/microbiologia , Sífilis/microbiologia , Treponema pallidum/isolamento & purificação , Corpo Vítreo/microbiologia , Adulto , Idoso , Humanos , Masculino , Reação em Cadeia da Polimerase
10.
Hum Exp Toxicol ; 26(1): 37-47, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17334178

RESUMO

Crotonaldehyde, an alpha,beta-unsaturated aldehyde, and a potent alkylating agent, is present in many foods and beverages, ambient air and tobacco smoke. A previous study indicated that two metabolites, 3-hydroxy-1-methylpropylmercapturic acid (HMPMA) and 2-carboxyl-l-methylethylmercapturic acid (CMEMA), were excreted in rat urine after subcutaneous injection of crotonaldehyde. Herein, we report the development of a method based on liquid chromatography with tandem mass spectrometry (LC-MS/MS) and deuterated analytes as internal standards, for the determination of HMPMA and CMEMA in human urine. The limits of quantification of the method were 92 and 104 ng/mL for HMPMA and CMEMA, respectively. The calibration curves for both compounds were linear up to 7500 ng/mL with R2 >0.99. It was found that cigarette smokers excreted about three to five-fold more HMPMA, and only slightly elevated amounts of CMEMA, in their urine compared to nonsmokers. In smokers, we also found significant correlations between the urinary excretion levels of HMPMA (but not CMEMA) and several markers of exposure for smoking, including the daily cigarette consumption, carbon monoxide in exhaled breath, salivary cotinine, and nicotine plus five of its major metabolites in urine. Smoking cessation or switching from smoking conventional cigarettes to experimental cigarettes with lower crotonaldehyde delivery led to significant reductions of urinary HMPMA excretion, but not CMEMA excretion. Alcohol consumption did not influence either urinary HMPMA or CMEMA excretion. We conclude that HMPMA is a potentially useful biomarker for smoking-related exposure to crotonaldehyde.


Assuntos
Acetilcisteína/análogos & derivados , Aldeídos/farmacocinética , Fumar/urina , Acetilcisteína/urina , Adulto , Idoso , Consumo de Bebidas Alcoólicas/urina , Biomarcadores/urina , Calibragem , Cromatografia Líquida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem
11.
J Laryngol Otol ; 131(6): 534-540, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28366182

RESUMO

BACKGROUND: Despite advances in endoscopic sinus surgery, frontal sinus obliteration is still indicated in some cases. Current options for obliteration include autologous and synthetic materials. The use of ß-tricalcium phosphate as a resorbable bone graft substitute is a good alternative for frontal sinus obliteration. This study aimed to report our experience with this material. METHODS: A retrospective chart review of patients who underwent frontal sinus obliteration at our clinic between 2008 and 2013 was performed. Demographic data, indications, previous surgery, and immediate and late complications were examined. Information on persisting symptoms and patient outcomes was collected using a telephone questionnaire in February 2016. RESULTS: None of the patients underwent further surgery for frontal sinus disease. All of them reported a good cosmetic result and symptom improvement. CONCLUSION: ß-tricalcium phosphate is a good, safe and cost-effective material for frontal sinus obliteration.


Assuntos
Substitutos Ósseos/uso terapêutico , Fosfatos de Cálcio/uso terapêutico , Seio Frontal/cirurgia , Mucocele/cirurgia , Doenças dos Seios Paranasais/cirurgia , Idoso , Idoso de 80 Anos ou mais , Regeneração Óssea , Feminino , Osso Frontal/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Terapia de Salvação/métodos , Resultado do Tratamento
12.
MMW Fortschr Med ; 147(39): 33-4, 36, 2005 Sep 29.
Artigo em Alemão | MEDLINE | ID: mdl-16245779

RESUMO

Chronic tonsillitis is a common disease entity which, on account of the possibility of the tonsils becoming a focus of infection, must not be made light of. The patient's complaints are highly uncharacteristic, and it is not always possible to establish the diagnosis on the local findings alone. Rather, the patient's history and general state of health must also be considered when considering the diagnosis. By reason of the pathogenesis, the treatment of choice can only be tonsillectomy.


Assuntos
Infecções Bacterianas/diagnóstico , Tonsilectomia , Tonsilite/diagnóstico , Abscesso/diagnóstico , Abscesso/etiologia , Abscesso/cirurgia , Adulto , Infecções Bacterianas/etiologia , Infecções Bacterianas/cirurgia , Criança , Doença Crônica , Humanos , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/etiologia , Infecções Estreptocócicas/cirurgia , Streptococcus pyogenes , Tonsilite/etiologia , Tonsilite/cirurgia
13.
MMW Fortschr Med ; 147(17): 45-6, 49, 2005 Apr 28.
Artigo em Alemão | MEDLINE | ID: mdl-15903059

RESUMO

An appropriate indication for laser tonsillotomy is non-infectious obstructive hyperplasia in children. As a rule, these children suffer from pronounced rhonchopathy, which may be associated with episodes of apnea. Furthermore, disordered articulation and problems with eating have also been described. With increasing age hyperplastic tonsils may repeatedly become inflamed, with the result that tonsillar tissue undergoes changes that further the development of chronic tonsillitis. The indication for tonsillotomy should, however, not be applied in children older than 6 years. In children beyond this age tonsillectomy is recommended, not least due to the fact that the immunological "learning phase" is usually complete around the age of 6.


Assuntos
Terapia a Laser , Tonsila Palatina/cirurgia , Tonsilectomia , Criança , Pré-Escolar , Humanos , Hiperplasia/patologia , Hiperplasia/cirurgia , Tonsila Palatina/patologia , Tonsilite
14.
Int J Oncol ; 18(4): 669-81, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11251160

RESUMO

The proper structure of the extracellular matrix, in particular of the basement membrane and the adjacent interstitial matrix, are essential prerequisites for a proper function of tissues. Invasive growth in malignant tumors is associated with a destruction of various matrix structures. Due to extensive recent analyses significant advances have been made in the knowledge of the structure of the extracellular matrix, the composition of its most important constituents, their metabolism and that of matrix degrading enzymes. This information provides insight into the pathophysiology of malignant growth. Thereby, it has been shown that malignant tumor growth is associated with a loss of basement membrane (BM) material which, however, disappears not homogeneously, but affects various BM components to different degree. The loss of an intact BM as the first barrier is therefore the initial step of tumor invasion. Despite this loss there is evidence that the de novo synthesis of BM constituents in tumor and adjacent stromal cells is enhanced. Thus, it is obvious that BM material is degraded during the invasion process to significant degree. In addition, since there is a positive correlation between the amount of retained peritumoral BM and a higher degree of tumor cell differentiation the amount of retained BM material seems to represent a marker for the biological behaviour of the tumor cells. The loss of BM material is well explained by a significant expression of major matrix degrading enzymes, the matrix metalloproteinases (MMPs) both on the mRNA and protein level. Here again, there is considerable data indicating that both tumor and stroma cells are involved in the MMP synthesis. In addition to the loss of BM substances, the interstitial extracellular matrix (ECM) is disarranged. This disarrangement may comprise enhanced de novo synthesis ("desmoplasia") or dissolution by distinct MMPs (collagenases, such as MMP-1) reflecting obviously different reaction statuses of the stromal cells. Finally, significant work has been done on the elucidation of the role of regulating cytokine systems. To this regard, particular attention has been paid to the TGF-beta system and it has been shown that the major three isoforms of TGF-betas are upregulated both in tumor and stroma cells. Since the TGF-beta-effect is mainly mediated by a particular signalling system via the TGF-beta-receptors (TBRs), the investigation of this system has provided considerable insight into the role of TBRs which are now known to represent the most potent tumor suppressor genes. Thus frequent mutations in the TBR-II gene, one of the three TBRs, in various carcinomas suggest that these molecular alterations are responsible for both the loss of the control of cellular proliferation (in tumor cells) and altered matrix metabolism (in tumor and stroma cells). The further analysis of this major cytokine system therefore will provide us with major insights into the molecular abnormalities of invasive tumor growth.


Assuntos
Membrana Basal/fisiologia , Matriz Extracelular/fisiologia , Invasividade Neoplásica , Neoplasias/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Membrana Basal/ultraestrutura , Colágeno/metabolismo , Colágeno/farmacologia , Regulação da Expressão Gênica , Humanos , Metaloproteinases da Matriz/metabolismo , Neoplasias/patologia , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta/genética
15.
Int J Oncol ; 18(5): 1045-51, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11295055

RESUMO

In previous studies, we demonstrated a loss of major basement membrane (BM) components in laryngeal squamous cell carcinomas and provided initial evidence that this was of potential prognostic significance. In our current study, we extended the panel of BM antibodies and enlarged our study group in order to perform a multivariate statistical analysis. We analyzed 26 laryngeal squamous cell carcinomas immunohistochemically for the distribution of the BM-components collagen IV, collagen VII, laminin-1, laminin-5, perlecan and fibronectin. The resulting data were correlated with clinical prognostic factors and statistical correlation coefficients were determined for independent uni- and multivariate analysis. All carcinomas analyzed revealed defects of the peritumoral BM with more extensive loss of collagen VII than collagen IV, laminin-1, perlecan and fibronectin. Laminin-5 in contrast was present even in poorly differentiated tumors showing an enhanced intracytoplasmatic staining in the tumor cells. Furthermore, our statistical analysis did not show independent prognostic significance of any of the BM-components. Our observations indicate a divergence between the loss of several major BM-components (collagens IV, VII, laminin-1, perlecan) and an enhanced deposition of laminin-5. This suggests a severely altered cell-matrix interaction, since laminin-5 links the collagen VII-containing anchoring fibrils to cell receptors of the integrin type.


Assuntos
Carcinoma de Células Escamosas/patologia , Proteínas da Matriz Extracelular/metabolismo , Neoplasias Laríngeas/patologia , Proteínas de Neoplasias/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Membrana Basal/metabolismo , Membrana Basal/patologia , Carcinoma de Células Escamosas/metabolismo , Diferenciação Celular , Feminino , Humanos , Técnicas Imunoenzimáticas , Neoplasias Laríngeas/metabolismo , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Prognóstico , Análise de Sobrevida
16.
Int J Oncol ; 6(6): 1193-202, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21556658

RESUMO

We review the current knowledge on alterations of the major basement membrane (BM) components and their cellular integrin receptors in benign and malignant tumors of epithelial and mesenchymal origin. While benign tumors usually exhibit a continous BM, recent analyses provide evidence that invasive growth of carcinomas coincides with (a) a loss in a proper BM, (b) changes in the type of integrin receptor expression and (c) the retained ability of certain tumor cells to synthesize matrix components. This latter aspect has been regarded as a potentially beneficial 'host' mechanism against invasive growth. This assumption is strongly supported by the finding of a positive correlation between the extent of BM loss and both a lesser degree of tumor differentiation and a worse prognosis of tumor growth. The resulting concept indicates that in carcinomas an imbalance in the cell-matrix interaction is the leading element in invasive growth. In mesenchymal tumors a somewhat different role of the BM can be observed. Thus, the qualitative and quantitative expression of major BM components in benign mesenchymal tumors closely relates to the BM pattern of normal tissues providing a histogenetically oriented classification of benign mesenchymal tumors. Most well-differentiated sarcomas retain a BM pattern close to that of the histogenetically related tissue, although in poorly differentiated sarcomas no such attribution to a histogenetic orientation of the tumor cells can be found.

17.
Insect Biochem Mol Biol ; 27(2): 133-47, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9066123

RESUMO

Pyruvate carboxylase (PC, pyruvate: carbon dioxide ligase [ADP-forming], EC 6.4.1.1) was purified from the yellow fever mosquito, Aedes aegypti. The purified PC showed two polypeptides of similar M(r) (133 and 128 k). The N-terminal sequences of both polypeptides were shown to be very similar, if not identical. A polyclonal antiserum against the 133 kDa polypeptide cross-reacted strongly with the 128 kDa polypeptide. PC was found in all tissues examined. Using a semi-quantitative Western blot assay, PC was shown to be concentrated in the indirect flight muscles and fat body preparations. The ratios of the 133 to 128 kDa polypeptides were shown to differ in various tissues and an Aedes albopictus cell line. The indirect flight muscle was the only tissue in which the 128 kDa polypeptide was more abundant, while both the midgut and the cell line showed almost exclusively the 133 kDa polypeptide. Both peptides were present in varying amounts in brain, malpighian tubule, ovary and fat body preparation. The two isoforms of PC could play different roles in the flight muscle and other tissues. Clones covering a complete cDNA of PC of A. aegypti were obtained using a directional approach. The 3952 bp nucleotide sequence, including a 3585 bp coding region, was determined from these cDNA clones. The deduced 1195 amino acid sequence has a calculated M(r) of 132,200. A putative mitochondrial targeting sequence was determined by comparing the deduced amino acid sequence to the N-terminal sequences of the mature protein. The presence of a mitochondrial targeting sequence indicates that the mosquito PC encoded by the cloned cDNA may be localized in the mitochondria. After the targeting sequence, three functional domains were identified in the following order; biotin carboxylase (BC), carboxyltransferase (CT) and biotin carboxyl carrier protein (BCCP). The mosquito PC showed very high similarity to PCs from other sources (55.1-75.2% identity). Genomic Southern analysis indicated that there could be two similar PC genes or a single PC gene with allelic polymorphism in the A. aegypti genome. The evolutionary relationship of PCs among different organisms was consistent with the accepted evolutionary relationship of their host organisms. The evolution of the domain structures of the biotin-dependent carboxylases including PC was also investigated. This analysis indicates that biotin-dependent carboxylases evolved from a common origin. The analysis also provides evidence for early gene duplication events that shaped the family of biotin-dependent carboxylases. Clear evidence for the coevolution of BC and BCCP domains is presented, although they are associated with very different CT domains and the relative position of the three functional domains varies between members of the biotin-dependent carboxylases.


Assuntos
Aedes/enzimologia , Proteínas de Insetos/química , Piruvato Carboxilase/química , Animais , Sequência de Bases , Linhagem Celular , DNA Complementar , Dosagem de Genes , Proteínas de Insetos/classificação , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Dados de Sequência Molecular , Peptídeos/metabolismo , Filogenia , Piruvato Carboxilase/classificação , Piruvato Carboxilase/genética , Piruvato Carboxilase/metabolismo , Distribuição Tecidual
18.
Insect Biochem Mol Biol ; 28(12): 915-25, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9887508

RESUMO

Vitelline envelope genes from the mosquito Aedes aegypti were analyzed with respect to their DNA sequences, genomic representation, temporal and spatial expression profiles and response to 20-hydroxyecdysone. Genomic clones of three vitelline envelope genes, 15a-1, 15a-2 and 15a-3 were isolated. Southern analysis indicates that all three genes are represented by a single copy in the genome. The deduced amino acid sequences of all three vitelline envelope genes contain a conserved region of 46 residues that overlaps with a region that is conserved in four Drosophila melanogaster vitelline envelope genes. DNA was sequenced flanking the 15a-1, 15a-2 and 15a-3 coding regions. A 360 bp sequence 5' of the 15a-2 coding region was identified with 72% identity to a sequence upstream of the Ae. aegypti VgA1 vitellogenin gene. The temporal patterns of 15a-1, 15a-2 and 15a-3 expression, as determined by Northern analysis, were similar. The spatial patterns of expression, as determined by whole-mount in situ hybridization, differed between the three genes. 15a-1 and 15a-3 were only expressed in the middle and posterior regions of the follicle, while 15a-2 was also expressed at the anterior region. Vitelline envelope gene expression was higher in ovaries that were dissected at 0, 2 and 10 h following a blood meal and then incubated in vitro for 10 h in medium containing 10(-5) M 20-hydroxyecdysone, compared to ovaries that were incubated without hormone.


Assuntos
Aedes/genética , Proteínas do Ovo/genética , Proteínas de Insetos/genética , Insetos Vetores/genética , Proteínas de Membrana/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Southern Blotting , Clonagem Molecular , DNA Complementar , Ecdisterona/farmacologia , Feminino , Expressão Gênica , Ligação Genética , Dados de Sequência Molecular , Ovário/efeitos dos fármacos , Polimorfismo de Fragmento de Restrição , Regiões Promotoras Genéticas , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Fatores de Tempo , Distribuição Tecidual , Transcrição Gênica , Membrana Vitelina , Febre Amarela
19.
Insect Biochem Mol Biol ; 25(8): 939-58, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7550249

RESUMO

A genomic clone of the Aedes aegypti vitellogenin A1 gene was sequenced including 2015 bp of 5' untranscribed sequence, 6369 bp of open reading frame interrupted by two introns, and a short 3' untranslated region. Primer extension was used to identify the transcription initiation site. The amino termini of the large and small subunits were located by N-terminal sequencing of vitellin purified from eggs. The length of the signal sequence and the position of the cleavage site between the two subunits were also determined. Three sequential imperfect repeats were found near the beginning of the small subunit. The sequence of the coding region appears to be polymorphic. Comparison of the signal sequences of seven insect vitellogenin genes revealed several conserved leucines, and a conserved position of an intron. However, the signal sequences are not conserved between these genes and the yolk protein genes of Cyclorraphid Dipteran insects. The cleavage sites between the small and large subunits in the vitellogenins of the mosquito, A. aegypti, sawfly, Athalia rosae, boll weevil, Anthonomus grandis, and silkworm, Bombyx mori are flanked by sequences rich in serine. Pairwise dot matrix analysis at the protein level showed that the mosquito, boll weevil and silkworm vitellogenins are significantly related with approx. 50% similarity. One region of the three insect vitellogenin genes, near the N-terminal of the large subunit, showed the highest levels of similarity, from 57.5 to 64.4%. The position of cysteines in insect vitellogenins is conserved, particularly in the C-terminus of the large subunit. Dot matrix comparison of the mosquito vitellogenin with that of Xenopus laevis and Caenorhabditis elegans showed much lower, but still significant degrees of relationship. Pairwise comparisons of the mosquito vitellogenin and the Drosophila melanogaster yolk proteins did not show significant similarities. Potential regulatory regions in the mosquito VgA1 gene were identified by comparison to regulatory elements known from other organisms, especially D. melanogaster, which could provide useful information for further functional analysis.


Assuntos
Aedes/genética , Genes de Insetos , Vitelogeninas/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sequência Conservada , Dípteros/metabolismo , Proteínas do Ovo , Variação Genética , Invertebrados , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Vertebrados
20.
Hum Pathol ; 29(5): 447-54, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9596267

RESUMO

In this study, we evaluated immunohistochemically the composition of the tumor-associated epithelial basement membrane (BM) in a series of 66 laryngeal squamous cell carcinomas (SCC) and compared these results with those from 10 cases with laryngeal dysplasia and five cases with normal mucosa (controls). The major BM components collagen IV and VII, laminin-1, perlecan (heparan sulfate proteoglycan), and fibronectin were evaluated. The extent of the retained BM material was quantified by semiautomated morphometry. A subsequent statistical analysis correlated the immunohistochemical findings with the histopathologically evaluated degree of tumor cell differentiation. In our series, we observed a distinct correlation between the degree of tumor cell differentiation and the amount of retained BM material. The loss of BM affected the various components differently, with a more extensive loss of collagen VII even in highly differentiated tumors and a progressive loss of collagen IV immunostaining with decreasing tumor cell differentiation. With respect to the other BM components, a stepwise loss of BM material also was seen with decreasing degree of the tumor cell differentiation. This loss, however was not at a statistically significant level, so these parameters did not show further statistically relevant data. In dysplastic lesions (regardless of the degree of dysplasia), focal BM disruptions were seen that affected the various BM components to a very similar extent. Our observations provide evidence that laryngeal carcinomas show a progressive loss of BM material along with decreasing tumor cell differentiation. This loss of BM, however, affects the various BM components differently. This indicates a dysregulation of the BM, either induced by uncoordinated neosynthesis or selectively enhanced degradation by proteases or both. Finally, the BM analysis may provide information on the biological course of the tumors. The loss of collagen VII may serve as a marker for "early" invasive tumor growth, whereas the amount of collagen IV provides significant information on the loss of tumor cell differentiation.


Assuntos
Membrana Basal/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Laríngeas/patologia , Adulto , Idoso , Membrana Basal/metabolismo , Biomarcadores Tumorais , Carcinoma de Células Escamosas/metabolismo , Colágeno/metabolismo , Feminino , Fibronectinas/metabolismo , Proteoglicanas de Heparan Sulfato/metabolismo , Humanos , Imuno-Histoquímica , Laminina/metabolismo , Neoplasias Laríngeas/metabolismo , Masculino , Pessoa de Meia-Idade
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