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1.
Opt Express ; 28(10): 14627-14637, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403500

RESUMO

Femtosecond laser machining is a complex process, owing to the high peak intensities involved. Modelling approaches for the prediction of final sample quality based on photon-atom interactions are therefore challenging to extrapolate up to the microscale and beyond. The problem is compounded when multiple exposures are used to produce a final structure, where surface modifications from previous exposures must be taken into consideration. Neural network approaches allow for the automatic creation of a model that accounts for these challenging processes, without any physical knowledge of the processes being programmed by a specialist. We present such a network for the prediction of surface quality for multi-exposure femtosecond machining on a 5µm electroless nickel layer deposited on copper, where each pulse is uniquely spatially shaped using a spatial light modulator. This neural network modelling method accurately predicts the surface profile after three, sequential, overlapping exposures of dissimilar intensity patterns. It successfully reproduces such effects as the sub-diffraction limit machining feasible with multiple exposures, and the smoothing effect on edge-burr from previous exposures expected in multi-exposure laser machining.

2.
J Small Anim Pract ; 62(1): 19-27, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33107069

RESUMO

INTRODUCTION: To report the clinical presentation, laboratory and imaging findings, treatment and outcome of abdominal cryptococcosis in dogs and cats in Australia. MATERIALS AND METHODS: Canine and feline cases from Australia were retrospectively identified (2000 to 2018) via laboratory and referral centre searches for abdominal cryptococcosis diagnosed by cytology (needle aspirates) or histopathology (biopsy or necropsy) of abdominal organs/tissues. Signalment, presenting complaints, clinical signs, laboratory findings, medical imaging, latex cryptococcal antigen agglutination test (LCAT) titres, treatment and outcome data was collected. RESULTS: Thirty-eight cases were included (35 dogs, three cats) in the study. Median age of presentation was 2 years for dogs and 6 years for cats. Common presenting complaints included vomiting (23/38), lethargy (19/38) and inappetence/anorexia (15/38). Abdominal ultrasound (25/38 cases) revealed mesenteric and intestinal lesions in most of the cases. On surgical exploration, seven cases had an intestinal lesion associated with an intussusception. Nineteen cases had a pre-treatment LCAT performed, with a median initial titre of 1:2048 (range 1:2 to 65,536). Twenty-four cases (23 dogs, one cat) received treatment, either medical, surgical or both. Median survival time for cases with combined medical and surgical treatment, surgical treatment alone or medical treatment alone was 730, 140 and 561 days, respectively. Eleven remain alive at the time of follow up. CLINICAL SIGNIFICANCE: Abdominal cryptococcosis although rare should be a considered as a diagnostic possibility in an especially young dog presenting with gastro-intestinal signs. Older dogs can also present with this condition and should not be euthanised based on imaging alone due to the likenesses with neoplasia. With appropriate treatment and monitoring many dogs may have a prolonged survival period and some may be cured.


Assuntos
Doenças do Gato , Criptococose , Doenças do Cão , Animais , Austrália , Doenças do Gato/diagnóstico , Gatos , Criptococose/diagnóstico , Criptococose/tratamento farmacológico , Criptococose/veterinária , Doenças do Cão/diagnóstico , Cães , Estudos Retrospectivos
3.
Front Chem ; 9: 628852, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33681146

RESUMO

Biliproteins are a unique class of photosynthetic proteins in their diverse, and at times, divergent biophysical function. The two contexts of photosynthetic light harvesting and photoreception demonstrate characteristically opposite criteria for success, with light harvesting demanding structurally-rigid chromophores which minimize excitation quenching, and photoreception requiring structural flexibility to enable conformational isomerization. The functional plasticity borne out in these two biological contexts is a consequence of the structural plasticity of the pigments utilized by biliproteins-linear tetrapyrroles, or bilins. In this work, the intrinsic flexibility of the bilin framework is investigated in a bottom-up fashion by reducing the active nuclear degrees of freedom through model dipyrrole subunits of the bilin core and terminus free of external protein interactions. Steady-state spectroscopy was carried out on the dipyrrole (DPY) and dipyrrinone (DPN) subunits free in solution to characterize their intrinsic spectroscopic properties including absorption strengths and nonradiative activity. Transient absorption (TA) spectroscopy was utilized to determine the mechanism and kinetics of nonradiative decay of the dipyrrole subunits, revealing dynamics dominated by rapid internal conversion with some Z→E isomerization observable in DPY. Computational analysis of the ground state conformational landscapes indicates enhanced complexity in the asymmetric terminal subunit, and the prediction was confirmed by heterogeneity of species and kinetics observed in TA. Taken together, the large oscillator strengths (f ∼ 0.6) of the dipyrrolic derivatives and chemically-efficient spectral tunability seen through the ∼100 nm difference in absorption spectra, validate Nature's "selection" of multi-pyrrole pigments for light capture applications. However, the rapid deactivation of the excited state via their natural torsional activity when free in solution would limit their effective biological function. Comparison with phytochrome and phycocyanin 645 crystal structures reveals binding motifs within the in vivo bilin environment that help to facilitate or inhibit specific inter-pyrrole twisting vital for protein operation.

4.
Foot Ankle Surg ; 15(2): 62-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19410170

RESUMO

BACKGROUND: In June 2006, the post operative plaster immobilisation protocol for patients undergoing hindfoot and ankle surgery, at our institution, changed from multiple plaster changes to the immediate application of a definitive removable and reusable split synthetic cast. This study aims to assess the savings to the hospital and patient, following this change in practice. METHODS: A retrospective analysis of plaster room records from June 2005 to June 2007 was performed. The difference in cost to the hospital of the two different post operative journeys was then calculated. RESULTS: Two-hundred and twenty-two patients from 2005 to 2006 were managed at a total cost of 97,125 euro. From 2006 to 2007, 203 patients were managed with the new technique at a total cost of 37,860 euro. The net saving to the hospital of this change in practice was 251 euro per patient and 50,953 euro in total, while 203 patient visits and costs associated therewith were also saved. CONCLUSIONS: This study demonstrates how small changes in local practice can result in significant financial and temporal savings for hospitals and patients.


Assuntos
Tornozelo/cirurgia , Moldes Cirúrgicos/economia , Pé/cirurgia , Padrões de Prática Médica/economia , Redução de Custos , Custos e Análise de Custo , Humanos , Padrões de Prática Médica/estatística & dados numéricos , Estudos Retrospectivos , Resultado do Tratamento
5.
Nurse Educ Pract ; 22: 1-6, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27871040

RESUMO

Technology is having a profound effect on education in the 21st century and nurse educators are being challenged to integrate technological innovation to assist students in their learning. This paper reports a study on the introduction of smart mobile technology to support student learning in the clinical environment. In a climate of collaborative inquiry, clinical lecturers and two researchers from the same department carried out a project in three phases: formation, implementation and analysis. Following the formation phase, six clinical lecturers adopted iPads to support their clinical teaching (implementation phase). At this time they also kept reflective journals. In the analysis phase a thematic analysis of the data from the journals and from a focus group found both enabling and constraining factors influenced the use of iPads by clinical lecturers. The themes categorised as enablers were: resources and technology; and, management and technology support. Those identified as barriers or constraining factors were: clinical staff engagement; and lecturer experience with technology. Student engagement and learning, and connectivity were both enabling and constraining factors. This paper concludes that the use of a mobile device such as an iPad can enhance teaching in clinical settings but that in order for such devices to be successfully integrated into clinical teaching consideration needs to be given to professional development needs, adequate resourcing and technology support.


Assuntos
Atitude do Pessoal de Saúde , Atitude Frente aos Computadores , Computadores de Mão/estatística & dados numéricos , Ensino , Bacharelado em Enfermagem , Tecnologia Educacional/métodos , Docentes de Enfermagem , Grupos Focais , Humanos , Pesquisa Qualitativa
6.
Cancer Res ; 54(24): 6365-9, 1994 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-7987829

RESUMO

Acute promyelocytic leukemia (FAB M3) is distinguished by the presence of the t(15;17) and clinical response to all-trans retinoic acid (RA) treatment. Acute promyelocytic leukemia is associated with a chromosomal translocation which results in the fusion of genes encoding a putative transcription factor (PML) and the retinoic acid receptor alpha (RAR alpha). It is suggested that the PML/RAR alpha fusion protein functions as an inhibitor of myeloid differentiation. The potential use of ribozymes as therapeutic agents has been investigated in the present study. Hammerhead ribozymes, which by hybridizing to both PML and RAR alpha sequences discriminate between the fusion transcript and the normal transcripts from the nonrearranged alleles, were designed and synthesized. Two hammerhead cleavage sites were targeted: site 1, an AUU located 4 nucleotides 3' to the fusion junction; and site 2, a UUC located 26 nucleotides 3' to the junction. Both sites are located in the RAR alpha portion of the fusion transcript. Using a full-length PML/RAR alpha RNA or an RNA corresponding to 788 nucleotides of the PML/RAR alpha mRNA and a full-length RAR alpha RNA or an RNA corresponding to 960 nucleotides of the RAR alpha mRNA as model substrates, the catalytic behavior of several ribozymes was studied. A modified hammerhead directed against site 2 displayed the highest degree of selectivity for PML/RAR alpha. It is hypothesized that ribozyme-mediated inactivation of PML/RAR alpha provides a new approach to study the role of PML/RAR alpha in the deregulated growth and RA response of acute promyelocytic leukemia.


Assuntos
Leucemia Promielocítica Aguda/metabolismo , RNA Catalítico/metabolismo , RNA Mensageiro/metabolismo , Receptores do Ácido Retinoico/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Bases , Cromossomos Humanos Par 15/genética , Cromossomos Humanos Par 17/genética , Humanos , Leucemia Promielocítica Aguda/genética , Dados de Sequência Molecular , Estrutura Secundária de Proteína , RNA Catalítico/química , RNA Catalítico/genética , Translocação Genética/genética
7.
Cancer Res ; 59(8): 1973-9, 1999 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-10213509

RESUMO

Allelic losses on the short arm of chromosome 8 (8p) have been reported as frequent events in several cancers, including lung. However, no comprehensive mapping analysis of chromosome 8p in lung cancer tumors has been performed, and no data are available about the stage at which these abnormalities occur during the multistage development of lung cancer. Using 26 microsatellite markers, we mapped the chromosome 8 regions frequently deleted in lung cancer in 13 small cell carcinoma and 17 non-small cell lung carcinoma cell lines and in 68 microdissected archival primary lung tumors (22 small cell lung carcinomas, 25 squamous cell carcinomas, and 21 adenocarcinomas). We also studied the role of 8p deletions in lung cancer pathogenesis by examining 95 microdissected normal epithelium and preneoplastic samples from 11 surgically resected squamous cell lung carcinomas and from 58 bronchoscopy biopsy samples obtained from 31 current and former smokers. High frequencies of deletions at 8p21-23 regions were detected in lung cancer cell lines and in primary lung tumors. Deletions commenced early during the multistage development of lung cancer at the hyperplasia/metaplasia stage in cancer patients and in smokers without cancer. Allelic deletions persisted for up to 48 years after smoking cessation. There was a progressive increase of the overall 8p21-23 loss of heterozygosity frequency and in the size of the deleted region with increasing severity of histopathological preneoplastic changes. In epithelial samples from resected squamous cell lung carcinomas, we compared the presence of loss of heterozygosity at 8p21-23 with deletions at chromosomes 3p and 9p. Of interest, the pattern of deletions was not random, and 8p21-23 allelic losses always followed 3p deletions and usually followed 9p deletions. We conclude that 8p21-23 deletions are frequent and early events in the pathogenesis of lung carcinomas.


Assuntos
Cromossomos Humanos Par 8 , Perda de Heterozigosidade , Neoplasias Pulmonares/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Brônquios/fisiologia , Deleção Cromossômica , Mapeamento Cromossômico , Epitélio/fisiologia , Feminino , Genes Supressores de Tumor , Humanos , Masculino , Pessoa de Meia-Idade , Fumar/genética
8.
J Clin Oncol ; 2(2): 112-7, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6699662

RESUMO

One hundred fifty-eight patients receiving Adriamycin underwent 226 transjugular biopsy procedures. The specimens were evaluated by electron microscopy for evidence of drug-related cardiotoxicity. Ejection fraction determinations using echocardiographic or nuclear techniques at rest were available for 69% and 81% of the patients, respectively. Analysis of the data revealed a correlation between cumulative Adriamycin dose and biopsy grade (p less than 0.02). No similar relationship existed between cumulative Adriamycin dose and ejection fractions obtained at rest or between biopsy grades and ejection fractions. In patients who underwent serial endomyocardial biopsies and serial ejection fraction determinations, the correlation between changes in biopsy grade and ejection fraction was poor. A change in resting ejection fraction detected by either method did not reliably predict a change in biopsy grade. The poor correlation between ejection fractions and biopsy grades could be due in part to the sensitivity and specificity of the Adriamycin-related structural changes in contrast to the wider range of disease processes that can affect myocardial function, and to the fact that structural changes often precede the ejection fraction abnormalities. The greater sensitivity and specificity of the biopsy grade should prove useful in reducing the risks associated with evaluating new anthracyclines and potential myocardial protectors of Adriamycin toxicity.


Assuntos
Biópsia , Débito Cardíaco , Doxorrubicina/efeitos adversos , Cardiopatias/diagnóstico , Miocárdio/ultraestrutura , Volume Sistólico , Biópsia/efeitos adversos , Doxorrubicina/uso terapêutico , Cardiopatias/induzido quimicamente , Cardiopatias/patologia , Humanos , Neoplasias/tratamento farmacológico
9.
J Clin Oncol ; 2(3): 207-14, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6321689

RESUMO

One hundred patients with non-small cell lung cancer were entered into a randomized evaluation of two schedules of doxorubicin combined with ftorafur, cyclophosphamide, and cisplatin (FACP). Doxorubicin was given either weekly at 20 mg/m2, or every three weeks (standard) at 60 mg/m2. Fifty-two patients were randomized to the FACP/weekly doxorubicin arm and 48 patients to the FACP/standard doxorubicin arm. The FACP/weekly doxorubicin regimen was associated with higher complete and partial remission rates (31% versus 19%), longer response duration (median, 33 versus 21 weeks), and longer survival duration for responders (median, 58 versus 50 weeks). These differences were not significant. Less neutropenia (p = 0.01) and less infectious morbidity (p = 0.05) were observed in the FACP/weekly doxorubicin arm. Twenty-eight patients underwent 35 endomyocardial biopsies to assess doxorubicin-induced cardiotoxicity. Sixteen biopsies were performed in 12 patients receiving cumulative doxorubicin doses ranging from 250 to 1,190 mg/m2 within the FACP/weekly doxorubicin arm. Nineteen biopsies were performed in 16 patients receiving cumulative doxorubicin doses ranging from 250 to 540 mg/m2 within the FACP/standard doxorubicin regimen. The FACP/weekly doxorubicin regimen was associated with significantly lower cardiotoxicity scores (p = 0.01). This study indicates that weekly administered doxorubicin is as effective and less cardiotoxic than the standard schedule.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Doxorrubicina/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Adenocarcinoma/mortalidade , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Medula Óssea/efeitos dos fármacos , Carcinoma de Células Pequenas/mortalidade , Carcinoma de Células Escamosas/mortalidade , Cisplatino/administração & dosagem , Ensaios Clínicos como Assunto , Ciclofosfamida/administração & dosagem , Relação Dose-Resposta a Droga , Doxorrubicina/efeitos adversos , Esquema de Medicação , Feminino , Coração/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Distribuição Aleatória , Tegafur/administração & dosagem
10.
J Clin Oncol ; 13(11): 2827-34, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7595745

RESUMO

PURPOSE: To estimate the incidence of idarubicin (IDA)-related cardiomyopathy in acute myeloid leukemia (AML) and myelodysplasia (MDS). PATIENTS AND METHODS: We analyzed a group of 127 AML/MDS patients who received IDA-based induction and postremission or salvage therapy and achieved a complete remission (CR) that lasted > or = 12 weeks for the development of IDA-related congestive heart failure (CHF). CHF was defined as definite if a resting left ventricular ejection fraction (LVEF) of < or = 45% measured by radionuclide ventriculogram (RV) accompanied the clinical diagnosis of CHF, which had to be made during or within 6 months of receiving IDA and for which no other cause was apparent; without RV confirmation, the diagnosis was considered probable. Patients who had RVs performed were evaluated for decreasing LVEF. Older age (> or = 70 years), prior/sequential anthracycline/mitoxantrone (anthraquinone) therapy, and cardiac disease/hypertension were evaluated as risk factors for the development of CHF. RESULTS: One hundred fifteen patients were assessable (median age, 40 years; median dose, 96 mg/m2). Sixty-five had RVs performed during therapy; 43 had risk factors. The probability of IDA-related cardiomyopathy was 5% at a cumulative IDA dose of 150 to 290 mg/m2, with 18 patients receiving doses greater than 150 mg/m2. At a cumulative IDA dose of 150 mg/m2, the probability of a mild or greater asymptomatic decrease probability of a mild or greater asymptomatic decrease in LVEF (> or = 10% to a level < or = 50%) was 18%, whereas the probability of a moderate or greater asymptomatic decrease in LVEF (> or = 15% to a level < or = 45%) was 7%. No patient with asymptomatic LVEF decreases developed CHF. CHF was more frequent in patients with prior/sequential exposure to anthracyclines/mitoxantrone (P = .01). CONCLUSION: In this patient group, IDA-related cardiomyopathy was uncommon with cumulative IDA doses of up to 290 mg/m2. Asymptomatic LVEF decreases were more frequent, but their predictive value for the development of CHF is unclear.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Insuficiência Cardíaca/induzido quimicamente , Coração/efeitos dos fármacos , Idarubicina/efeitos adversos , Leucemia Mieloide Aguda/tratamento farmacológico , Síndromes Mielodisplásicas/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antineoplásicos/administração & dosagem , Feminino , Coração/fisiopatologia , Insuficiência Cardíaca/fisiopatologia , Humanos , Idarubicina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Indução de Remissão , Estudos Retrospectivos , Fatores de Risco , Volume Sistólico/efeitos dos fármacos
11.
J Clin Oncol ; 17(5): 1425-34, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10334527

RESUMO

PURPOSE: To determine the efficacy and safety profile, including the risk for cardiac toxicity, of liposome-encapsulated doxorubicin (TLC D-99), fluorouracil (5-FU), and cyclophosphamide as first-line chemotherapy in patients with metastatic breast cancer (MBC). PATIENTS AND METHODS: Forty-one women were registered in this phase II study. All patients had measurable disease and no previous chemotherapy for MBC. Treatment consisted of TLC D-99 60 mg/m2 and cyclophosphamide 500 mg/m2 on day 1 and 5-FU 500 mg/m2 on days 1 and 8 every 3 weeks. Serial cardiac monitoring, including endomyocardial biopsies, was performed. RESULTS: The overall response rate was 73% (95% confidence interval, 57% to 86%). The median duration of response was 11.2 months, the median time to treatment failure was 8.1 months, and the median overall survival duration was 19.4 months. The median number of cycles per patient was 10. The median cumulative dose of TLC D-99 was 528 mg/m2. Ten patients required hospitalization for febrile neutropenia. Nausea/vomiting, stomatitis, and fatigue higher than grade 2 occurred in 12%, 15%, and 41% of patients, respectively. Twenty-one patients reached a cumulative doxorubicin dose greater than 500 mg/m2. Three patients (7%) were withdrawn from the study due to protocol-defined cardiac toxicity, two because of a decrease in left ventricular ejection fraction to < or = 40%, and one because her endomyocardial biopsy result was grade 1.5. One patient had congestive heart failure that was probably nonanthracycline related. CONCLUSION: This chemotherapy regimen, including TLC D-99, was highly active against MBC and associated with low cardiac toxicity despite high cumulative doses of doxorubicin.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Adulto , Idoso , Neoplasias da Mama/patologia , Ciclofosfamida/administração & dosagem , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Portadores de Fármacos , Feminino , Fluoruracila/administração & dosagem , Humanos , Lipossomos , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Volume Sistólico/efeitos dos fármacos , Função Ventricular Esquerda/efeitos dos fármacos
12.
Clin Cancer Res ; 5(1): 17-23, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9918198

RESUMO

Recent allelotyping studies suggest that allelic losses at one or both arms of chromosome 4 are frequent in several tumor types. Cytogenetic studies of malignant mesothelioma (MM) and comparative genomic hybridization analyses of small cell lung carcinoma (SCLC) suggest that chromosome 4 deletions may also play a role in these tumor types, although these results have not been confirmed by allelotyping. In an effort to more precisely identify and map the locations of putative tumor suppressor gene(s) on chromosome 4 involved in the pathogenesis of these tumors, we performed loss of heterozygosity studies using 16 polymorphic microsatellite markers. After precise microdissection of archival surgical cases, we studied DNA obtained from 20 MMs, 21 SCLCs, and 20 non-SCLCs (NSCLCs). In addition, DNA from 14 SCLC and 17 NSCLC cell lines and corresponding B lymphoblastoid lines were studied. In MM and SCLC, we observed frequent losses at three nonoverlapping regions: (a) 4q33-34 (region R1; >80%); (b) 4q25-26 (region R2; >60%); and (c) 4p15.1-15.3 (region R3; >50%). Losses at these sites occurred at lower frequencies in NSCLC (>20-30%). Data from tumors and cell lines were similar. In MM and SCLC, the most frequently observed pattern was loss at all three regions. However, in NSCLC, the most frequent pattern was loss at R3 alone. Our study has delineated three nonoverlapping regions of frequent deletions on chromosome 4 in MM and SCLC, suggesting that there may be three putative suppressor genes on chromosome 4, the inactivation of which may be important in the pathogenesis of these tumor types.


Assuntos
Carcinoma de Células Pequenas/genética , Deleção Cromossômica , Cromossomos Humanos Par 4 , Neoplasias Pulmonares/genética , Mesotelioma/genética , Carcinoma Pulmonar de Células não Pequenas/genética , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Humanos , Perda de Heterozigosidade , Repetições de Microssatélites , Inclusão em Parafina , Células Tumorais Cultivadas
13.
Clin Cancer Res ; 6(7): 2604-10, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10914700

RESUMO

To better understand the pathways involved in the pathogenesis of small cell lung carcinoma (SCLC), we compared the patterns of molecular changes present in these tumors and their accompanying bronchial epithelium with those present in the other two major types of lung cancer [squamous cell carcinoma (SQC) and adenocarcinoma (ADC)]. We obtained DNA from 68 microdissected invasive lung tumors (22 SCLCs, 21 ADCs, and, 25 SQCs) and 119 noncontiguous foci of histologically normal or hyperplastic epithelia from 10 tumors of each histological type. We determined loss of heterozygosity and microsatellite alterations at 12 chromosomal regions frequently deleted in lung cancers using 19 polymorphic microsatellite markers. Our major findings are as follows: (a) the mean index of allelic loss in SCLC (0.85) and SQC (0.71) tumors was higher than that in ADC (0.39) tumors; (b) although there was considerable overlap, each tumor type had a characteristic pattern of allelic loss; (c) most samples of bronchial epithelium accompanying SCLC (90%) had allelic loss at one or more loci compared with samples accompanying SQC (54%) or ADC (10%); (d) the mean index of allelic loss was much higher in bronchial epithelial samples from SCLC (0.27) than in those from SQC (0.08) or ADC (0.01); and (e) although the mean indices of microsatellite alterations in the tumor types were similar, the bronchial epithelial samples accompanying SCLC had a 10-fold higher mean index (0.063) than those accompanying SQC (0.006) or ADC (0.006). Our findings indicate that extensive genetic damage in the accompanying normal and hyperplastic bronchial epithelium is characteristic of SCLC tumors and suggest major differences in the pathogenesis of the three major lung cancer types.


Assuntos
Carcinoma de Células Pequenas/genética , Mapeamento Cromossômico , Perda de Heterozigosidade , Neoplasias Pulmonares/genética , Repetições de Microssatélites , Polimorfismo Genético , Mucosa Respiratória/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Alelos , Carcinoma de Células Pequenas/patologia , Carcinoma de Células Pequenas/cirurgia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , DNA de Neoplasias/genética , Marcadores Genéticos , Humanos , Hiperplasia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Estadiamento de Neoplasias , Reação em Cadeia da Polimerase , Mucosa Respiratória/patologia , Estudos Retrospectivos
14.
Aust Vet J ; 83(5): 270-5, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15957386

RESUMO

OBJECTIVE: To investigate a possible association between Bull Terrier polycystic kidney disease (BTPKD) and cardiac disease, to determine the prevalence of mitral valve disease (MVD) and left ventricular outflow tract obstruction (LVOTO) in the Australian Bull Terrier population, and to compare auscultation and echocardiography in detection of cardiac disease in Bull Terriers. DESIGN: Ninety-nine Bull Terriers, ranging in age from 8 weeks to 13 years and 11 months were auscultated and examined using renal ultrasonography; 86 were also examined using echocardiography. The prevalence and severity of heart defects in dogs with BTPKD was compared with that in dogs without BTPKD. RESULTS: Nineteen of these 99 dogs were diagnosed with BTPKD. Forty-two percent of Bull Terriers with BTPKD and 28% of those without BTPKD had murmurs characteristic of mitral regurgitation or LVOTO. How recently an animal was descended from an ancestor with BTPKD was associated with presence (P = 0.008) and loudness of a murmur (P = 0.009). Overall, echocardiography detected MVD in 39% of Bull Terriers, with increased prevalence in older animals (P = 0.003). Mitral stenosis was found in eight cases. Fifty-three percent of dogs in this study had evidence of LVOTO, with obstruction consisting of a complex of lesions including dynamic or fixed subvalvular LVOTO, significantly narrowed left ventricular outflow tract or valvular aortic stenosis. Dogs with BTPKD, or those descended from dogs with BTPKD, were more likely to have MVD (P = 0.006), and while LVOTO was not more common in these dogs, if they did have LVOTO, they were more likely to have severe obstruction than dogs with no ancestors with BTPKD (analysed in three ways P = 0.028 to 0.001). In this study, 46% of Bull Terriers without a murmur or arrhythmia had cardiac disease detected on echocardiographic examination. CONCLUSION: Cardiac disease, especially MVD and LVOTO, was common in Bull Terriers in this study, and those with BTPKD had an increased risk of cardiac abnormalities. Auscultation did not detect a significant number of Bull Terriers with cardiac disease.


Assuntos
Doenças do Cão/diagnóstico por imagem , Ecocardiografia/veterinária , Insuficiência da Valva Mitral/veterinária , Rim Policístico Autossômico Dominante/veterinária , Obstrução do Fluxo Ventricular Externo/veterinária , Animais , Animais Recém-Nascidos , Cruzamento , Doenças do Cão/diagnóstico , Doenças do Cão/genética , Cães , Ecocardiografia/métodos , Feminino , Predisposição Genética para Doença , Ventrículos do Coração/diagnóstico por imagem , Masculino , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/genética , Rim Policístico Autossômico Dominante/complicações , Rim Policístico Autossômico Dominante/diagnóstico por imagem , Rim Policístico Autossômico Dominante/genética , Obstrução do Fluxo Ventricular Externo/complicações , Obstrução do Fluxo Ventricular Externo/diagnóstico por imagem , Obstrução do Fluxo Ventricular Externo/genética
15.
J Cereb Blood Flow Metab ; 8(5): 681-90, 1988 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-3417795

RESUMO

One of the factors limiting the accuracy of the 15O steady-state method for the measurement of regional cerebral blood flow and oxygen metabolism is the requirement that a constant arterial blood concentration be maintained over long periods. A new method has been developed to correct for the variation of the arterial concentration in the C15O2 and 15O2 steady-state inhalation technique. The time course of the arterial activity is obtained by multiple sampling over the study period. The same 15O model as is used in the steady-state method is employed but is solved without assuming equilibrium. Look-up tables are generated to relate flow and oxygen extraction fraction to tissue activity, and from them the regional parameters are estimated. Theory and simulation studies suggest that substantial improvement in accuracy can be obtained with no increase in statistical error. The validity of the method was checked experimentally by making repeated measurements in the same subject after perturbing the gas delivery. The conventional steady-state method showed significantly larger deviations in repeat measurement than did the new method. Thus, it is concluded that the proposed method is superior.


Assuntos
Circulação Cerebrovascular , Radioisótopos de Oxigênio , Adulto , Artérias/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Radioisótopos de Carbono , Humanos , Masculino , Métodos , Cintilografia
16.
J Cereb Blood Flow Metab ; 9(6): 859-73, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2511212

RESUMO

A practical method has been developed that, using 11CO2 and positron emission tomography (PET), computes and maps (a) "effective pH" (pHt), a weighted average of intra- and extracellular pH, and (b) "clearance" (K1), product of blood flow and 11CO2 extraction. This method, together with measurements of cerebral blood flow (CBF) and oxygen extraction fraction (OEF), was applied to 12 patients with cerebral ischemia or stroke. The regional K1 was positively correlated with CBF (n = +0.78). The k1/CBF ratio, representing the extraction fraction ratio of 11CO2 to H2 15O, was negatively correlated with CBF (r = -0.54), suggesting that 11CO2 extraction decreases as flow increases. In five acute stroke patients within 2 days of onset, the injured cortex had lower CBF (20.6 ml/min/100 g), higher OEF (78.1%), and lower pHt (6.96) than the contralateral cortex (CBF = 41.4 ml/min/100 g, OEF = 53.3%, pHt = 7.00), suggesting intracellular acidosis with intact cell membranes. In three stroke patients 5-8 days after onset, the injured cortex had higher CBF (60.9 ml/min/100 g), lower OEF (32.0%), and higher pHt (7.12) than the contralateral cortex (CBF = 45.3 ml/min/100 g, OEF = 58.0%, pHt = 7.06), which suggested an increase in extracellular volume compartment reflecting loss of cell membrane integrity. This method provides information on the regional tissue acid-base status and cell membrane integrity, which may be prognostic of tissue viability.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Dióxido de Carbono , Circulação Cerebrovascular , Transtornos Cerebrovasculares/diagnóstico por imagem , Concentração de Íons de Hidrogênio , Tomografia Computadorizada de Emissão/métodos , Adulto , Idoso , Encéfalo/fisiopatologia , Isquemia Encefálica/fisiopatologia , Radioisótopos de Carbono , Transtornos Cerebrovasculares/fisiopatologia , Feminino , Humanos , Ataque Isquêmico Transitório/diagnóstico por imagem , Ataque Isquêmico Transitório/fisiopatologia , Cinética , Masculino , Matemática , Pessoa de Meia-Idade , Modelos Cardiovasculares , Modelos Neurológicos , Valores de Referência
17.
Am J Med ; 76(4): 759-66, 1984 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-6711582

RESUMO

A 37-year-old woman presented with acute psychosis and cognitive impairment. Skull x-ray showed an enlarged sella turcica with erosion of the floor. Endocrinologic workup suggested the diagnosis of Cushing's disease and hyperprolactinemia. She had no cushingoid feature, and the only physical sign was mild generalized obesity. She showed a paradoxic response to dexamethasone suppression, and underwent trans-sphenoidal resection of a pituitary macroadenoma. Electron microscopy showed the tumor to be a Crooke's cell adenoma. Results of immunohistochemical staining were positive only for ACTH and beta-endorphin. The neuropsychiatric manifestations resolved after surgery.


Assuntos
Adenoma/diagnóstico , Síndrome de Cushing/diagnóstico , Neoplasias Hipofisárias/diagnóstico , Transtornos Psicóticos/diagnóstico , Adenoma/ultraestrutura , Adulto , Síndrome de Cushing/patologia , Feminino , Humanos , Microscopia Eletrônica , Neoplasias Hipofisárias/ultraestrutura
18.
Am J Surg Pathol ; 3(2): 137-45, 1979 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-532845

RESUMO

Three cases of a morphologically distinctive "sclerosis" of lymph nodes are presented. Two patients experienced recurring lymph node enlargement with associated mild malaise over an extended period. The first patient had unilateral axillary lymph node enlargement, but was asymptomatic and died of chronic obstructive pulmonary disease 17 years later with no evidence of lymph node enlargement at autopsy. Each patient had at least transient hypergammaglobulinemia, one with elevated IgM and IgA, one with elevated IgM, and one (from 1958) not further analyzed. Lymph node biopsies revealed extensive deposition of eosinophilic material in all three patients. Identical changes in lymph nodes have been described in chronic diseases. The eosinophilic material may be related to amyloid, but differs from it histochemically and ultrastructurally. The relationship of this lesion to the few cases reported as amyloidosis presenting as lymph node enlargement is discussed. Malignant lymphoma with sclerosis is the most important consideration in the differential diagnosis.


Assuntos
Hipergamaglobulinemia/patologia , Doenças Linfáticas/patologia , Adulto , Amiloidose/patologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Esclerose
19.
Am J Surg Pathol ; 7(2): 171-7, 1983 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6859392

RESUMO

Among 32 neuroendocrine carcinomas of the skin, 11 were from patients with previous or concomitant squamous carcinoma. The medical records and pathologic material for these 11 cases were reviewed, and the diagnosis of neuroendocrine carcinoma was confirmed in each instance by electron microscopy. In two cases, the squamous and neuroendocrine carcinomas were admixed, but each preserved its identity and transition between the two was not identified. Despite the lack of evidence for origin from a single cell, the observations nevertheless indicate a common carcinogenetic influence for squamous and neuroendocrine carcinomas of the skin.


Assuntos
Adenocarcinoma/ultraestrutura , Carcinoma de Células Escamosas/ultraestrutura , Neoplasias Cutâneas/ultraestrutura , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Am J Surg Pathol ; 19(9): 1010-20, 1995 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7661274

RESUMO

We describe a vasoproliferative nodular spindle-cell lesion representing a variant of vascular transformation of lymph-node sinuses and designated a nodular spindle-cell vascular transformation of lymph nodes. The lesion is most frequently identified in retroperitoneal lymph nodes excised in association with radical nephrectomies for renal cell carcinoma, but it can also be present in association with other malignant tumors. Occasionally it is seen in superficial lymph nodes in patients with no history of malignant neoplasms. This lesion can be confused with Kaposi's sarcoma or with a metastatic sarcomatoid carcinoma because of its spindle-cell composition, cellularity, occasional high mitotic activity, and frequent occurrence in the regional lymphatic drainage of a known malignancy.


Assuntos
Carcinoma/patologia , Linfonodos/irrigação sanguínea , Linfonodos/patologia , Metástase Linfática , Sarcoma de Kaposi/patologia , Adulto , Idoso , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/patologia , Diagnóstico Diferencial , Feminino , Humanos , Imuno-Histoquímica , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Espaço Retroperitoneal
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