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2.
Oncogene ; 36(35): 4997-5005, 2017 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-28459465

RESUMO

Inturned (INTU), a cilia and planar polarity effector, performs prominent ciliogenic functions during morphogenesis, such as in the skin. INTU is expressed in adult tissues but its role in tissue maintenance is unknown. Here, we report that the expression of the INTU gene is aberrantly elevated in human basal cell carcinoma (BCC), coinciding with increased primary cilia formation and activated hedgehog (Hh) signaling. Disrupting Intu in an oncogenic mutant Smo (SmoM2)-driven BCC mouse model prevented the formation of BCC through suppressing primary cilia formation and Hh signaling, suggesting that Intu performs a permissive role during BCC formation. INTU is essential for intraflagellar transport A complex assembly during ciliogenesis. To further determine whether Intu is directly involved in the activation of Hh signaling downstream of ciliogenesis, we examined the Hh signaling pathway in mouse embryonic fibroblasts, which readily responds to the Hh pathway activation. Depleting Intu blocked Smo agonist-induced Hh pathway activation, whereas the expression of Gli2ΔN, a constitutively active Gli2, restored Hh pathway activation in Intu-deficient cells, suggesting that INTU functions upstream of Gli2 activation. In contrast, overexpressing Intu did not promote ciliogenesis or Hh signaling. Taken together, data obtained from this study suggest that INTU is indispensable during BCC tumorigenesis and that its aberrant upregulation is likely a prerequisite for primary cilia formation during Hh-dependent tumorigenesis.


Assuntos
Carcinoma Basocelular/metabolismo , Cílios/metabolismo , Cílios/patologia , Proteínas Hedgehog/metabolismo , Proteínas de Membrana/genética , Neoplasias Cutâneas/metabolismo , Animais , Carcinoma Basocelular/genética , Carcinoma Basocelular/patologia , Células Cultivadas , Modelos Animais de Doenças , Feminino , Proteínas Hedgehog/genética , Humanos , Masculino , Proteínas de Membrana/biossíntese , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Transdução de Sinais , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/patologia , Transfecção
3.
Intern Med J ; 46(11): 1297-1306, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27502031

RESUMO

BACKGROUND: Cardiotoxicity resulting in heart failure is a devastating complication of cancer therapy. A patient may survive cancer only to develop heart failure (HF), which has a higher mortality rate than some cancers. AIM: This study aimed to describe the characteristics and outcomes of HF in patients with blood or breast cancer after chemotherapy treatment. METHODS: Queensland Cancer Registry, Death Registry and Hospital Administration records were linked (1996-2009). Patients were categorised as those with an index HF admission (that occurred after cancer diagnosis) and those without an index HF admission (non-HF). RESULTS: A total of 15 987 patients was included, and 1062 (6.6%) had an index HF admission. Median age of HF patients was 67 years (interquartile range 58-75) versus 54 years (interquartile range 44-64) for non-HF patients. More men than women developed HF (48.6% vs 29.5%), and a greater proportion in the HF group had haematological cancer (83.1%) compared with breast cancer (16.9%). After covariate adjustment, HF patients had increased mortality risk compared with non-HF patients (hazard ratios 1.67 (95% confidence interval, 1.54-1.81)), and 47% of the index HF admission occurred within 1 year from cancer diagnosis and 70% within 3 years. CONCLUSION: Cancer treatment may place patients at a greater risk of developing HF. The onset of HF occurred soon after chemotherapy, and those who developed HF had a greater mortality risk.


Assuntos
Neoplasias da Mama/complicações , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/mortalidade , Neoplasias Hematológicas/complicações , Adulto , Idoso , Neoplasias da Mama/terapia , Feminino , Neoplasias Hematológicas/terapia , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Prognóstico , Queensland , Sistema de Registros , Estudos Retrospectivos , Fatores de Risco , Análise de Sobrevida
4.
Clin Exp Dermatol ; 41(5): 498-501, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26848819

RESUMO

Palmoplantar pustulosis (PPP) is a chronic pustular dermatitis of the palms and soles, which is frequently associated with significant pruritus and pain, often limiting daily activities. We present the case of a 36-year-old man with severe PPP who had treatment failure with multiple medical therapies but showed marked improvement with high-dose rate brachytherapy. Brachytherapy has the advantage of providing a conformal dose distribution over complex curved surfaces, such as the foot and ankle. Our observations suggest that brachytherapy may be a well-tolerated treatment option for patients with severe, refractory PPP.


Assuntos
Braquiterapia/métodos , Dermatoses do Pé/radioterapia , Dermatoses da Mão/radioterapia , Psoríase/radioterapia , Adulto , Humanos , Masculino , Resultado do Tratamento
5.
Am J Transplant ; 16(7): 2158-71, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26749226

RESUMO

Facial transplantation is a life-changing procedure for patients with severe composite facial defects. However, skin is the most immunogenic of all transplants, and better understanding of the immunological processes after facial transplantation is of paramount importance. Here, we describe six patients who underwent full facial transplantation at our institution, with a mean follow-up of 2.7 years. Seum, peripheral blood mononuclear cells, and skin biopsy specimens were collected prospectively, and a detailed characterization of their immune response (51 time points) was performed, defining 47 immune cell subsets, 24 serum cytokines, anti-HLA antibodies, and donor alloreactivity on each sample, producing 4269 data points. In a nonrejecting state, patients had a predominant T helper 2 cell phenotype in the blood. All patients developed at least one episode of acute cellular rejection, which was characterized by increases in interferon-γ/interleukin-17-producing cells in peripheral blood and in the allograft's skin. Serum monocyte chemotactic protein-1 level was significantly increased during rejection compared with prerejection time points. None of the patients developed de novo donor-specific antibodies, despite a fourfold expansion in T follicular helper cells at 1 year posttransplantation. In sum, facial transplantation is frequently complicated by a codominant interferon-γ/interleukin-17-mediated acute cellular rejection process. Despite that, medium-term outcomes are promising with no evidence of de novo donor-specific antibody development.


Assuntos
Transplante de Face/efeitos adversos , Rejeição de Enxerto/diagnóstico , Sobrevivência de Enxerto/imunologia , Interferon gama/imunologia , Interleucina-17/imunologia , Células Th1/imunologia , Adulto , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/etiologia , Humanos , Testes de Função Renal , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Transplantados
6.
Gene Ther ; 23(1): 78-85, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26204499

RESUMO

PPARδ (peroxisome proliferator-activated receptor δ) mediates inflammation in response to lipid accumulation. Systemic administration of a PPARδ agonist can ameliorate atherosclerosis. Paradoxically, genetic deletion of PPARδ in hematopoietic cells led to a reduction of atherosclerosis in murine models, suggesting that downregulation of PPARδ expression in these cells may mitigate atherogenesis. To advance this finding forward to potential clinical translation through hematopoietic stem cell transplantation-based gene therapy, we employed a microRNA (miRNA) approach to knock down PPARδ expression in bone marrow cells followed by transplantation of the cells into LDLR-/- mice. We found that knockdown of PPARδ expression in the hematopoietic system caused a dramatic reduction in aortic atherosclerotic lesions. In macrophages, a key component in atherogenesis, knockdown of PPARδ led to decreased expression of multiple pro-inflammatory factors, including monocyte chemoattractant protein-1 (MCP-1), interleukin (IL)-1ß and IL-6. Expression of CCR2, a receptor for MCP-1, was also decreased. The downregulation of pro-inflammatory factors is consistent with significant reduction of macrophage presence in the lesions, which may also be attributable to elevation of ABCA1 (ATP-binding cassette, subfamily A, member 1) and depression of adipocyte differentiate-related protein. Furthermore, the abundance of both MCP-1 and matrix metalloproteinase-9 proteins was reduced in plaque areas. Our results demonstrate that miRNA-mediated PPARδ knockdown in hematopoietic cells is able to ameliorate atherosclerosis.


Assuntos
Aterosclerose/genética , Terapia Genética/métodos , PPAR delta/genética , Transportador 1 de Cassete de Ligação de ATP/genética , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Animais , Aorta/patologia , Aterosclerose/prevenção & controle , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Regulação para Baixo , Feminino , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Macrófagos/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Knockout , MicroRNAs/genética , MicroRNAs/metabolismo , PPAR delta/metabolismo , Placa Aterosclerótica/genética , Placa Aterosclerótica/patologia , Receptores CCR2/genética , Receptores CCR2/metabolismo
7.
Int J STD AIDS ; 22(3): 155-9, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21464453

RESUMO

This study examined the prevalence and factors associated with Mycoplasma genitalium (MG) infection among HIV-positive women and the association between MG and vaginal HIV-1 RNA shedding. HIV-positive women attending an outpatient clinic in New Orleans, Louisiana, USA, from 2002 to 2005 were examined for a battery of sexually transmitted infections (STIs) and underwent a behavioural survey. A selected subset had a measurement of vaginal shedding analysed. Of the 324 HIV-positive women, 32 (9.9%) were infected with MG. HIV-positive women with MG were more likely to be co-infected with Neisseria gonorrhoeae and Chlamydia trachomatis and to have had ≥1 male sexual partners in the last month. In the subset (n = 164), no differences were found in the presence of detectable vaginal HIV-1 RNA between women infected and not infected with MG (30.8% versus 34.8% shedding; P = 0.69). While MG was a common co-STI in this sample of HIV-positive women, it was not associated with vaginal HIV shedding.


Assuntos
Infecções por HIV/microbiologia , Infecções por Mycoplasma/virologia , Mycoplasma genitalium/isolamento & purificação , Vagina/virologia , Adolescente , Adulto , Estudos Transversais , Feminino , HIV/genética , Infecções por HIV/epidemiologia , Infecções por HIV/virologia , Humanos , Modelos Logísticos , Louisiana/epidemiologia , Pessoa de Meia-Idade , Análise Multivariada , Infecções por Mycoplasma/epidemiologia , Prevalência , RNA Viral/análise , Fatores de Risco , Fatores Socioeconômicos , Eliminação de Partículas Virais
8.
Gene Ther ; 18(8): 835-41, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21390069

RESUMO

Liver X receptors (LXRs) are implicated in the regulation of cholesterol homeostasis, inflammatory response and atherogenesis. Administration of LXR agonists inhibits the progress of atherosclerosis, and also increases plasma triglyceride levels, representing an obstacle to their use in treating this disease. The objective of this study was to develop an alternative approach that could overcome this obstacle. Eight-week-old low-density lipoprotein receptor-deficient (LDLR(-/-)) mice were transplanted with hematopoietic stem cell (HSC)-enriched bone marrow cells transduced with lentivectors expressing either green fluorescent protein (GFP) (Lenti-SP-GFP, control) or LXRα (Lenti-SP-LXRα) driven by a synthetic macrophage promoter. At 4 weeks post-transplant, the mice were fed with a Western diet for 8 weeks and then killed. Compared with Lenti-SP-GFP mice, the Lenti-SP-LXRα mice had a 30% reduction in atherosclerotic lesions, which was accompanied by increases in levels of macrophage expression of cholesterol efflux genes apolipoprotein E and ATP-binding cassette A1, as well as decreases in plasma inflammatory cytokines interleukin-6 and tumor necrosis factor-α. Intriguingly, a 50% reduction of plasma triglyceride level was also observed. We conclude that HSC-based macrophage LXRα gene therapy ameliorates the development of atherosclerosis along with an unexpected concomitant reduction of plasma triglyceride levels in LDLR(-/-) mice. These findings highlight the potential value of macrophage LXR expression as an avenue for therapeutic intervention against atherosclerosis.


Assuntos
Aterosclerose/terapia , Terapia Genética/métodos , Hipertrigliceridemia/terapia , Macrófagos/metabolismo , Receptores Nucleares Órfãos/genética , Receptores de LDL/deficiência , Transportador 1 de Cassete de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Apolipoproteínas E/genética , Transplante de Medula Óssea/métodos , Feminino , Interleucina-6/sangue , Lentivirus , Receptores X do Fígado , Camundongos , Transdução Genética , Triglicerídeos/sangue , Fator de Necrose Tumoral alfa/sangue
9.
Acad Radiol ; 8(11): 1074-82, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11721807

RESUMO

RATIONALE AND OBJECTIVES: The authors developed a new adaptive module to improve their computer-assisted diagnostic (CAD) method for mass segmentation and classification. The goal was an adaptive module that used a novel four-channel wavelet transform with neural network rather than a two-channel wavelet transform with manual subimage selection. The four-channel wavelet transform is used for image decomposition and reconstruction, and a novel Kalman-filtering neural network is used for adaptive subimage selection. MATERIALS AND METHODS: The adaptive CAD module was compared with the nonadaptive module by comparing receiver operating characteristic curves for the whole CAD system. An image database containing 800 regions of interest enclosing all mass types and normal tissues was used for the relative comparison of system performance, with electronic ground truth established in advance. RESULTS: The receiver operating characteristic curves yield Az values of 0.93 and 0.86 with and without the adaptive module respectively, suggesting that overall CAD performance is improved with the adaptive module. CONCLUSION: The results of this study confirm the importance of using a new class of adaptive CAD methods that allow a more generalized application for larger image databases or images generated from different sensors or by means of direct x-ray detection, as required for clinical trials.


Assuntos
Mamografia/métodos , Redes Neurais de Computação , Intensificação de Imagem Radiográfica/métodos , Humanos , Curva ROC
10.
J Am Acad Dermatol ; 45(6 Suppl): S212-4, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11712062

RESUMO

The appearance of multiple seborrheic keratoses in association with underlying internal malignancy (known as the sign of Leser-Trelat) has generated much discussion and debate in the literature. However, comparatively few case reports exist that examine the appearance of multiple seborrheic keratoses associated with exfoliative erythroderma without underlying malignancy. We report 2 cases in which multiple, biopsy-proven seborrheic keratoses appeared in conjunction with erythrodermic skin eruptions. The underlying diseases in these 2 patients included psoriasis and an eczematous drug eruption; in both cases the erythroderma resolved with appropriate treatment. After resolution of the erythroderma, the newly developed seborrheic keratoses proceeded to involute and gradually fall off. Neither of the patients exhibited any evidence of internal malignancy. These cases represent the first reports of psoriasis and drug eruption as causes of erythroderma-induced transient eruptive seborrheic keratoses. Clinical and pathologic findings are consistent with previous descriptions of this entity.


Assuntos
Toxidermias/diagnóstico , Ceratolíticos/efeitos adversos , Ceratose Seborreica/diagnóstico , Psoríase/tratamento farmacológico , Idoso , Diagnóstico Diferencial , Toxidermias/etiologia , Toxidermias/patologia , Feminino , Humanos , Ceratose Seborreica/induzido quimicamente , Ceratose Seborreica/patologia , Masculino
11.
Cancer Control ; 8(5): 399-406, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11579335

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) has the potential to become a useful adjunct in breast imaging. Contrast-enhanced breast MRI has demonstrated a high sensitivity in the detection of invasive breast cancer. In clinical studies, breast MRI has often altered the course of patient care. Although promising results have been generated, MRI of the breast is currently in a development stage. METHODS: The authors reviewed the literature on the potential indications, sensitivity, specificity, and limitations of MRI of the breast. RESULTS: Reported advantages of MRI of the breast over conventional imaging techniques include improved staging and treatment planning, enhanced evaluation of the augmented breast, better detection of recurrence, and improved screening of high-risk women. Contrast-enhanced breast MRI is a sensitive modality for detecting breast cancer, but its variable specificity is a major limitation. CONCLUSIONS: MRI of the breast is emerging as a valuable adjunct to mammography and sonography for specific clinical indications. Additional clinical studies that define indications, interpretation criteria, imaging parameters, and cost effectiveness are needed. A multi-institutional study designed to address these issues is in progress.


Assuntos
Neoplasias da Mama/diagnóstico , Mama , Imageamento por Ressonância Magnética/métodos , Implantes de Mama , Neoplasias da Mama/patologia , Feminino , Humanos , Programas de Rastreamento , Estadiamento de Neoplasias/métodos , Sensibilidade e Especificidade
12.
J Infect Dis ; 184(10): 1325-7, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11679923

RESUMO

To obtain information on the prevalence of anovulation and early menopause and on pituitary-gonadal function among human immunodeficiency virus type 1-infected women, a study was undertaken that used stored serum samples from women aged 20-42 years who participated in selected Adult AIDS Clinical Trials Group protocols. Defined progesterone and follicle-stimulating hormone (FSH) levels were considered presumptive evidence of ovulation and of menopause, respectively. Anovulation occurred in 16 (48%) of 33 women for whom progesterone levels were tested; early menopause occurred in 2 (8%) of 24 women for whom FSH levels were tested. No statistically significant differences were seen in the demographic and clinical characteristics of anovulatory and ovulatory women, although women who ovulated had higher CD4 T cell counts and were less likely to have reported a recent change in menstrual periods. These data support the findings of prior studies of increased frequency of amenorrhea and/or irregular menstrual cycles, particularly among women with lower CD4 T cell counts.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Anovulação/etiologia , HIV-1 , Menopausa Precoce , Síndrome da Imunodeficiência Adquirida/sangue , Síndrome da Imunodeficiência Adquirida/fisiopatologia , Adulto , Anovulação/sangue , Anovulação/epidemiologia , Contagem de Linfócito CD4 , Estudos de Coortes , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Avaliação de Estado de Karnofsky , Menopausa Precoce/sangue , Prevalência , Progesterona/sangue
13.
J Biol Chem ; 276(42): 39368-78, 2001 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-11483614

RESUMO

We have investigated the myeloid-specific transcriptional regulation of p67(phox), an essential component of phagocyte respiratory burst NADPH oxidase. Analysis was carried out on the p67(phox) 5'-flanking region from -3669 to -4 (relative to ATG), including the first exon and intron and part of the second exon. The construct extending from -985 to -4 produced the highest luciferase activity in myeloid HL-60 cells but was not active in HeLa or Jurkat cells, indicating myeloid-specific expression. Four active elements were identified: Sp1/Sp3 at -694, PU.1 at -289, AP-1 at -210, and PU.1/HAF1 at -182, the latter three being in the first intron. These cis elements bound their cognate transacting factors both in vitro and in vivo. Mutation of the Sp1, PU.1, or PU.1/HAF1 site each decreased promoter activity by 35-50%. Mutations in all three sites reduced promoter activity by 90%. However, mutation of the AP-1 site alone nearly abolished promoter activity. The AP-1 site bound Jun and Fos proteins from HL-60 cell nuclear extract. Co-expression with Jun B in AP-1-deficient cells increased promoter activity by 3-fold. These data show that full p67(phox) promoter activity requires cooperation between myeloid-specific and nonmyeloid transcription factors, with AP-1 being the most critical for function.


Assuntos
Regulação Enzimológica da Expressão Gênica , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Regiões Promotoras Genéticas , Fator de Transcrição AP-1/genética , Fator de Transcrição AP-1/metabolismo , Transcrição Gênica , Sequência de Bases , Sítios de Ligação , Núcleo Celular/metabolismo , Clonagem Molecular , Proteínas de Ligação a DNA/metabolismo , Desoxirribonuclease I/metabolismo , Regulação para Baixo , Éxons , Células HL-60 , Células HeLa , Humanos , Íntrons , Células Jurkat , Luciferases/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Mutação , Ligação Proteica , Estrutura Terciária de Proteína , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp3 , Fatores de Transcrição/metabolismo , Transfecção , Células Tumorais Cultivadas
14.
Ann N Y Acad Sci ; 936: 355-67, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11460492

RESUMO

Although hemostasis is the major role of fibrin in wound repair, once the clot is present the wound cells must deal with it. The invasion and clearing of fibrin by these cells involves multiple complex processes that may go array XXX and delay wound repair. A good example, of the latter is leg ulcers. These chronic wounds contain a plethora of proteases that digest fibronectin and growth factors in the fibrin clot resulting in a corrupt provisional matrix that no longer supports reepithelialization or granulation tissue formation. Every good wound care provider knows that these wounds will not heal unless the corrupt matrix is removed by vigorous debridement that stimulates the accumulation of a competent provisional matrix.


Assuntos
Fibrina/fisiologia , Cicatrização , Células Epiteliais/citologia , Tecido de Granulação , Humanos , Monócitos/citologia , Neovascularização Fisiológica , Neutrófilos/citologia
15.
J AAPOS ; 5(3): 178-83, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11404745

RESUMO

PURPOSE: The use of adjustable sutures in strabismus surgery has increased the rate of surgical success. Little data are available on the optimum timing for postoperative adjustment after strabismus surgery. We wanted to compare 2 common practices of adjustable suture technique after strabismus surgery. METHODS: Two comparable groups of 40 patients each, who had strabismus surgery with adjustable suture technique, were prospectively studied. Group A had early adjustment the same day of the surgery about 6 hours after the operation, and group B had late adjustment the next day about 24 hours after the operation. Subjective scoring tables were used to evaluate the pain felt by the patient before, during, and after the adjustment and any difficulties of the adjustment process. Requirements of postoperative pain medications and final alignment 6 weeks after surgery were also compared. RESULTS: Despite adequate statistical power, no significant differences were found between the groups regarding pain before, during, and after adjustment, difficulties performing the adjustment, and final alignment after 6 weeks (P > .05). Both adjustment schedules were equally associated with mild to moderate pain before, during, and after the adjustment. In the first 24 hours after surgery, no overall difference in the use of pain medications was found. Nausea and vomiting in the first 24 postoperative hours were more common in the early adjustment group (P = .02). CONCLUSION: The surgeon can feel free to choose the timing for postoperative adjustment. However, when performing an early adjustment, the surgeon should be especially prepared to control nausea and vomiting.


Assuntos
Músculos Oculomotores/cirurgia , Estrabismo/cirurgia , Técnicas de Sutura , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Náusea/etiologia , Náusea/prevenção & controle , Procedimentos Cirúrgicos Oftalmológicos , Dor/etiologia , Dor/prevenção & controle , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Poliglactina 910 , Estudos Prospectivos , Técnicas de Sutura/efeitos adversos , Suturas , Fatores de Tempo , Visão Binocular , Vômito/etiologia , Vômito/prevenção & controle
16.
Med Phys ; 28(2): 250-8, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11243350

RESUMO

High false-positive (FP) rate remains to be one of the major problems to be solved in CAD study because too many false-positively cued signals will potentially degrade the performance of detecting true-positive regions and increase the call-back rate in CAD environment. In this paper, we proposed a novel classification method for FP reduction, where the conventional "hard" decision classifier is cascaded with a "soft" decision classification with the objective to reduce false-positives in the cases with multiple FPs retained after the "hard" decision classification. The "soft" classification takes a competitive classification strategy in which only the "best" ones are selected from the pre-classified suspicious regions as the true mass in each case. A neural network structure is designed to implement the proposed competitive classification. Comparative studies of FP reduction on a database of 79 images by a "hard" decision classification and a combined "hard"-"soft" classification method demonstrated the efficiency of the proposed classification strategy. For example, for the high FP sub-database which has only 31.7% of total images but accounts for 63.5% of whole FPs generated in single "hard" classification, the FPs can be reduced for 56% (from 8.36 to 3.72 per image) by using the proposed method at the cost of 1% TP loss (from 69% to 68%) in whole database, while it can only be reduced for 27% (from 8.36 to 6.08 per image) by simply increasing the threshold of "hard" classifier with a cost of TP loss as high as 14% (from 69% to 55%). On the average in whole database, the FP reduction by hybrid "hard"-"soft" classification is 1.58 per image as compared to 1.11 by "hard" classification at the TP costs described above. Because the cases with high dense tissue are of higher risk of cancer incidence and false-negative detection in mammogram screening, and usually generate more FPs in CAD detection, the method proposed in this paper will be very helpful in improving the performance of early detection of breast cancer with CAD.


Assuntos
Diagnóstico por Computador/métodos , Mamografia , Fenômenos Biofísicos , Biofísica , Doenças Mamárias/classificação , Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Calcinose/classificação , Calcinose/diagnóstico por imagem , Árvores de Decisões , Diagnóstico por Computador/estatística & dados numéricos , Reações Falso-Positivas , Feminino , Lógica Fuzzy , Humanos , Mamografia/estatística & dados numéricos , Redes Neurais de Computação
17.
J AAPOS ; 5(1): 26-30, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11182669

RESUMO

PURPOSE: To determine whether normal maximum versions change as a function of age. METHODS: One hundred twenty-four healthy subjects without any history of strabismus, ocular or periocular surgery, or major illness were examined to confirm visual acuity better than 20/60 in each eye and the absence of strabismus. Maximum sustained elevation, depression, dextroversion, and levoversion were quantified by using a standardized lateral version light-reflex (LVR) test. RESULTS: Subjects ranged in age from 23 to 84 years. All LVR measurements were converted into degrees of eye rotation assuming standard globe size. For each maximal gaze position, the regression line (whether determined directly or scaled against historical normal values) was formed by plotting the LVR measurements versus age had a negative slope significantly different than zero (P =.0001 for all). Depression had a significantly smaller decrease in LVR measurement with age (-0.5% per year) than elevation (-1% per year, P = .0001), adduction (-0.8% per year, P = .0001), or abduction (-0.7% per year, P = .0017). Elevation had the largest decrease in LVR measurement with age compared with depression and abduction (P = .003). CONCLUSION: As measured by LVR, the maximum versions into extremes of gaze decrease by an average of 0.5% to 1.0% per year of life between the third and ninth decade. The version least affected and most affected by age is depression and elevation, respectively. Age should be considered when assessing versions for evidence of rectus muscle overaction and underaction.


Assuntos
Envelhecimento/fisiologia , Movimentos Oculares/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência
19.
Thorax ; 56(1): 9-12, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11120897

RESUMO

BACKGROUND: Passive smoking is a major cause of respiratory morbidity in children. However, few studies give accurate estimates of the health effects of passive smoking in children with asthma using an objective measure of exposure. The effects of passive smoking using salivary cotinine levels to measure exposure were investigated. METHODS: A sample of 438 children aged 2-12 years with asthma who had a parent who smoked were recruited in Tayside and Fife, Scotland. Health service contacts for asthma, assessed from GP case records, were used as a proxy for morbidity. RESULTS: A weak U-shaped relationship was found between the salivary cotinine level and health service contacts for asthma: compared with low cotinine levels those with moderate cotinine levels had a reduced contact rate (relative rate (RR) = 0.91, 95% confidence interval (CI) 0.80 to 1.05), whereas high cotinine levels were associated with an increased rate of contact (RR = 1.19, 95% CI 1.05 to 1.37). In contrast, a strong association was seen with the amount the parent reported smoking in front of the child: the higher the level the fewer visits were made for asthma (RR for everyday exposure = 0.66, 95% CI 0.56 to 0.77). This effect was not seen for non-respiratory visits. Demographic factors, age of child, and number of children in the family all had a powerful effect on the number of visits for asthma. The parents' perception of asthma severity was associated with visit frequency independent of actual severity (derived from drug treatment). CONCLUSION: High levels of parental smoking in the home are associated with a reduction in health care contacts for asthma. This could be due to a lack of awareness of asthma symptoms among heavy smokers or a reluctance to visit the GP. Children with asthma who have parents who smoke heavily may not be receiving adequate management.


Assuntos
Asma/epidemiologia , Serviços de Saúde da Criança/estatística & dados numéricos , Medicina de Família e Comunidade/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Poluição por Fumaça de Tabaco/efeitos adversos , Atitude Frente a Saúde , Biomarcadores/análise , Criança , Pré-Escolar , Cotinina/análise , Feminino , Humanos , Masculino , Morbidade , Pais/psicologia , Estudos Retrospectivos , Saliva/química , Escócia
20.
Int J Technol Assess Health Care ; 17(4): 626-31, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11758307

RESUMO

OBJECTIVES: To assess whether sentinel lymph node biopsy (SLNB), an alternative to axillary lymph node dissection in treating female breast cancer, affords any cost savings. METHODS: We profile cumulative treatment costs of 811 breast cancer patients, 555 of whom received SLNB. Univariate and multivariate statistical tests are used to appraise whether these cost profiles differ between SLNB and other patients. RESULTS: The statistical results are mixed. However, none supports the conjecture that SLNB necessarily lowers the cost of treating the average breast patient. CONCLUSIONS: SLNB may be cost-effective, but longer term costs and outcomes must be estimated before firm conclusions can be reached.


Assuntos
Neoplasias da Mama/cirurgia , Custos de Cuidados de Saúde/estatística & dados numéricos , Metástase Linfática/diagnóstico , Biópsia de Linfonodo Sentinela/economia , Axila/patologia , Biópsia/efeitos adversos , Biópsia/economia , Neoplasias da Mama/economia , Neoplasias da Mama/patologia , Análise Custo-Benefício , Feminino , Custos de Cuidados de Saúde/classificação , Humanos , Metástase Linfática/patologia , Análise Multivariada , Análise de Regressão , Avaliação da Tecnologia Biomédica/economia , Estados Unidos
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