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1.
BMC Public Health ; 16: 262, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26975718

RESUMO

BACKGROUND: Despite evidence supporting the preventative potential of HIV Treatment as Prevention (TasP), scientific experts and community stakeholders have suggested that the success of TasP at the population level will require overcoming a set of complex and population-specific implementation challenges. For example, the factors that might influence decisions to initiate 'early' treatment have yet to be thoroughly understood; neither have questions about the factors that enhance or impede their ability to achieve long-term adherence to ARVs or the social norms regarding various treatment regimens been examined in detail. This knowledge gap may hamper opportunities to effectively develop public health practices that are informed by the various challenges and opportunities related to TasP implementation and scale up. METHODS: Drawing on 50 in-depth, individual interviews with young men ages 18-24 in Vancouver, Canada, this study examines young men's perspectives regarding factors that might affect their engagement with TasP. RESULTS: While findings from the current study indicate young men generally have a high receptiveness to TasP, our findings also identify key social and structural forces that will warrant ongoing consideration for TasP implementation. For example, participants described how an enhanced awareness regarding treatment (including awareness of the universal availability of treatment in Vancouver) would be a necessary, but not sufficient, condition to decide to endorse TasP. Their decisions about engaging in HIV care in the context of TasP (e.g., HIV testing, treatment initiation, long-term adherence) also appear to be contingent on their ability to negotiate or 'balance' the risks and benefits to themselves and others. The findings also offer insight into the complex and sometimes controversial narratives that continue to emerge regarding risk compensation practices in the context of TasP. CONCLUSION: Based on the results of this study, we identify several areas that hold promise for informing the effective scale up of TasP, including new information regarding implementation adaptation strategies.


Assuntos
Infecções por HIV/prevenção & controle , Infecções por HIV/psicologia , Profilaxia Pré-Exposição/organização & administração , Adolescente , Conscientização , Canadá , Humanos , Entrevistas como Assunto , Masculino , Adesão à Medicação , Saúde Pública , Pesquisa Qualitativa , Adulto Jovem
2.
Breast Cancer Res Treat ; 143(1): 153-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24305976

RESUMO

Shear wave elastography (SWE) shows promise as an adjunct to greyscale ultrasound examination in assessing breast masses. In breast cancer, higher lesion stiffness on SWE has been shown to be associated with features of poor prognosis. The purpose of this study was to assess whether lesion stiffness at SWE is an independent predictor of lymph node involvement. Patients with invasive breast cancer treated by primary surgery, who had undergone SWE examination were eligible. Data were retrospectively analysed from 396 consecutive patients. The mean stiffness values were obtained using the Aixplorer® ultrasound machine from SuperSonic Imagine Ltd. Measurements were taken from a region of interest positioned over the stiffest part of the abnormality. The average of the mean stiffness value obtained from each of two orthogonal image planes was used for analysis. Associations between lymph node involvement and mean lesion stiffness, invasive cancer size, histologic grade, tumour type, ER expression, HER-2 status and vascular invasion were assessed using univariate and multivariate logistic regression. At univariate analysis, invasive size, histologic grade, HER-2 status, vascular invasion, tumour type and mean stiffness were significantly associated with nodal involvement. Nodal involvement rates ranged from 7 % for tumours with mean stiffness <50 kPa to 41 % for tumours with a mean stiffness of >150 kPa. At multivariate analysis, invasive size, tumour type, vascular invasion, and mean stiffness maintained independent significance. Mean stiffness at SWE is an independent predictor of lymph node metastasis and thus can confer prognostic information additional to that provided by conventional preoperative tumour assessment and staging.


Assuntos
Axila , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Técnicas de Imagem por Elasticidade , Linfonodos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Fatores de Risco
3.
Radiology ; 263(3): 673-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22523322

RESUMO

PURPOSE: To compare the histologic prognostic feature of invasive breast cancer with mean stiffness as measured with shear-wave elastography. MATERIALS AND METHODS: This retrospective study was exempted from ethical committee review. Patient consent for use of images for research was obtained. The study group comprised 101 consecutive women (age range, 38-91 years) with solid lesions identified during routine breast ultrasonography (US) performed between April 2010 and March 2011 and subsequently confirmed at histologic examination to be invasive cancers. Four elastographic images in two orthogonal planes were obtained of each lesion, and mean stiffness values were obtained from each image. Histologic findings following surgery were used for comparison, namely histologic grade, tumor type, invasive size, vascular invasion status, and lymph node status. Relationship between mean stiffness and histologic parameters was investigated by using a general linear model and multiple regression analysis. RESULTS: High histologic grade (P < .0001), large invasive size (P < .0001), lymph node involvement (P < .0001), tumor type (P < .0001), and vascular invasion (P = .0077) all showed statistically significant positive association with high mean stiffness values. Multiple linear regression indicated that invasive size is the strongest pathologic determinant of mean stiffness (P < .0001), with histologic grade also having significant influence (P = .022). CONCLUSION: In this study, breast cancers with higher mean stiffness values at shear-wave elastography had poorer prognostic features.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Invasividade Neoplásica/diagnóstico por imagem , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha , Neoplasias da Mama/patologia , Diagnóstico Diferencial , Feminino , Humanos , Modelos Lineares , Metástase Linfática , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Estudos Retrospectivos
4.
Breast Cancer Res ; 12(6): R104, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21122101

RESUMO

INTRODUCTION: Shear wave elastography is a new method of obtaining quantitative tissue elasticity data during breast ultrasound examinations. The aims of this study were (1) to determine the reproducibility of shear wave elastography (2) to correlate the elasticity values of a series of solid breast masses with histological findings and (3) to compare shear wave elastography with greyscale ultrasound for benign/malignant classification. METHODS: Using the Aixplorer® ultrasound system (SuperSonic Imagine, Aix en Provence, France), 53 solid breast lesions were identified in 52 consecutive patients. Two orthogonal elastography images were obtained of each lesion. Observers noted the mean elasticity values in regions of interest (ROI) placed over the stiffest areas on the two elastography images and a mean value was calculated for each lesion. A sub-set of 15 patients had two elastography images obtained by an additional operator. Reproducibility of observations was assessed between (1) two observers analysing the same pair of images and (2) findings from two pairs of images of the same lesion taken by two different operators. All lesions were subjected to percutaneous biopsy. Elastography measurements were correlated with histology results. After preliminary experience with 10 patients a mean elasticity cut off value of 50 kilopascals (kPa) was selected for benign/malignant differentiation. Greyscale images were classified according to the American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS). BI-RADS categories 1-3 were taken as benign while BI-RADS categories 4 and 5 were classified as malignant. RESULTS: Twenty-three benign lesions and 30 cancers were diagnosed on histology. Measurement of mean elasticity yielded an intraclass correlation coefficient of 0.99 for two observers assessing the same pairs of elastography images. Analysis of images taken by two independent operators gave an intraclass correlation coefficient of 0.80. Shear wave elastography versus greyscale BI-RADS performance figures were sensitivity: 97% vs 87%, specificity: 83% vs 78%, positive predictive value (PPV): 88% vs 84%, negative predictive value (NPV): 95% vs 82% and accuracy: 91% vs 83% respectively. These differences were not statistically significant. CONCLUSIONS: Shear wave elastography gives quantitative and reproducible information on solid breast lesions with diagnostic accuracy at least as good as greyscale ultrasound with BI-RADS classification.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mama/anatomia & histologia , Mama/patologia , Técnicas de Imagem por Elasticidade , Ultrassonografia Mamária , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Intraductal não Infiltrante/diagnóstico , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Lobular/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Fibroadenoma/diagnóstico por imagem , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
5.
AIDS Educ Prev ; 32(6): 528-542, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33779209

RESUMO

A wide variety of risk calculators estimate individuals' risk for HIV/sexually transmitted infections (STI) online. These tools can help target HIV/STI screening and optimize clinical decision-making. Yet, little evidence exists on suitable features for these tools to be acceptable to end-users. We investigated the desirable characteristics of risk calculators among STI clinic clients and testing service providers. Participants interacted with online HIV/STI risk calculators featuring varied target audiences, completion lengths, and message outputs. Thematic analysis of focus groups identified six qualities that would make risk calculators more appealing for online client use: providing personalized risk assessments based on users' specific sexual behaviors and HIV/STI-related concerns; incorporating nuanced risk assessment and tailored educational information; supplying quantifiable risk estimates; using non-stigmatizing and inclusive framing; including explanations and next steps; and developing effective and appropriate branding. Incorporating these features in the design of online HIV/STI risk calculators may improve their acceptability among end-users.


Assuntos
Infecções por HIV/prevenção & controle , Internet , Medição de Risco/métodos , Infecções Sexualmente Transmissíveis/prevenção & controle , Adulto , Feminino , Grupos Focais , Humanos , Masculino , Comportamento Sexual , Saúde Sexual
6.
Prev Vet Med ; 87(3-4): 358-72, 2008 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-18692923

RESUMO

At present, collective action regarding bio-security among UK cattle and sheep farmers is rare. Despite the occurrence of catastrophic livestock diseases such as bovine spongiform encephalopathy (BSE) and foot and mouth disease (FMD), within recent decades, there are few national or local farmer-led animal health schemes. To explore the reasons for this apparent lack of interest, we utilised a socio-psychological approach to disaggregate the cognitive, emotive and contextual factors driving bio-security behaviour among cattle and sheep farmers in the United Kingdom (UK). In total, we interviewed 121 farmers in South-West England and Wales. The main analytical tools included a content, cluster and logistic regression analysis. The results of the content analysis illustrated apparent 'dissonance' between bio-security attitudes and behaviour.(1) Despite the heavy toll animal disease has taken on the agricultural economy, most study participants were dismissive of the many measures associated with bio-security. Justification for this lack of interest was largely framed in relation to the collective attribution or blame for the disease threats themselves. Indeed, epidemic diseases were largely related to external actors and agents. Reasons for outbreaks included inadequate border control, in tandem with ineffective policies and regulations. Conversely, endemic livestock disease was viewed as a problem for 'bad' farmers and not an issue for those individuals who managed their stock well. As such, there was little utility in forming groups to address what was largely perceived as an individual problem. Further, we found that attitudes toward bio-security did not appear to be influenced by any particular source of information per se. While strong negative attitudes were found toward specific sources of bio-security information, e.g. government leaflets, these appear to simply reflect widely held beliefs. In relation to actual bio-security behaviours, the logistic regression analysis revealed no significant difference between in-scheme and out of scheme farmers. We concluded that in order to support collective action with regard to bio-security, messages need to be reframed and delivered from a neutral source. Efforts to support group formation must also recognise and address the issues relating to perceptions of social connectedness among the communities involved.


Assuntos
Agricultura/organização & administração , Doenças dos Bovinos/prevenção & controle , Doenças dos Ovinos/prevenção & controle , Criação de Animais Domésticos , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Surtos de Doenças/prevenção & controle , Surtos de Doenças/veterinária , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Entrevistas como Assunto , Ocupações , Ovinos , Doenças dos Ovinos/epidemiologia , Reino Unido/epidemiologia
7.
Acad Radiol ; 23(1): 53-61, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26564483

RESUMO

RATIONALE AND OBJECTIVES: To investigate if anisotropy at two-dimensional shear wave elastography (SWE) suggests malignancy and whether it correlates with prognostic and predictive factors in breast cancer. MATERIALS AND METHODS: Study group A of 244 solid breast lesions was imaged with SWE between April 2013 and May 2014. Each lesion was imaged in radial and in antiradial planes, and the maximum elasticity, mean elasticity, and standard deviation were recorded and correlated with benign/malignant status, and if malignant, correlated with conventional predictive and prognostic factors. The results were compared to a study group B of 968 solid breast lesions, which were imaged in sagittal and in axial planes between 2010 and 2013. RESULTS: Neither benign nor malignant lesion anisotropy is plane dependent. However, malignant lesions are more anisotropic than benign lesions (P ≤ 0.001). Anisotropy correlates with increasing elasticity parameters, breast imaging-reporting and data system categories, core biopsy result, and tumor grade. Large cancers are significantly more anisotropic than small cancers (P ≤ 0.001). The optimal anisotropy cutoff threshold for benign/malignant differentiation of 150 kPa(2) achieves the best sensitivity (74%) with a reasonable specificity (63%). CONCLUSIONS: Anisotropy may be useful during benign/malignant differentiation of solid breast masses using SWE. Anisotropy also correlates with some prognostic factors in breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Ultrassonografia Mamária/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anisotropia , Mama/patologia , Neoplasias da Mama/patologia , Diferenciação Celular , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Sensibilidade e Especificidade , Adulto Jovem
8.
Br J Radiol ; 89(1062): 20150865, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27007593

RESUMO

OBJECTIVE: To establish if palpable breast masses with benign greyscale ultrasound features that are soft on shear-wave elastography (SWE) (mean stiffness <50 kPa) have a low enough likelihood of malignancy to negate the need for biopsy or follow-up. METHODS: The study group comprised 694 lesions in 682 females (age range 17-95 years, mean age 56 years) presenting consecutively to our institution with palpable lesions corresponding to discrete masses at ultrasound. All underwent ultrasound, SWE and needle core biopsy. Static greyscale images were retrospectively assigned Breast Imaging Reporting and Data System (BI-RADS) scores by two readers blinded to the SWE and pathology findings, but aware of the patient's age. A mean stiffness of 50 kPa was used as the SWE cut-off for calling a lesion soft or stiff. Histological findings were used to establish ground truth. RESULTS: No cancer had benign characteristics on both modalities. 466 (99.8%) of the 467 cancers were classified BI-RADS 4a or above. The one malignant lesion classified as BI-RADS 3 was stiff on SWE. 446 (96%) of the 467 malignancies were stiff on SWE. No cancer in females under 40 years had benign SWE features. 74 (32.6%) of the 227 benign lesions were BI-RADS 3 and soft on SWE; so, biopsy could potentially have been avoided in this group. CONCLUSION: Lesions which appear benign on greyscale ultrasound and SWE do not require percutaneous biopsy or short-term follow-up, particularly in females under 40 years. ADVANCES IN KNOWLEDGE: None of the cancers had benign characteristics on both greyscale ultrasound and SWE, and 32% of benign lesions were BI-RADS 3 and soft on SWE; lesions that are benign on both ultrasound and SWE may not require percutaneous biopsy or short-term follow-up.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Técnicas de Imagem por Elasticidade/métodos , Palpação , Ultrassonografia Mamária/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego , Adulto Jovem
9.
Breast ; 26: 115-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27017250

RESUMO

PURPOSE: To define the shear wave elastography (SWE) characteristics of breast cancer histological types by size in a large cohort. METHODS: Consecutive patients with US visible masses underwent SWE. All those with confirmed invasive breast cancer were included in the study. Histologic type was ascertained from core biopsy and surgical resection specimens. For each type, mean and median values for Emean and Emax were ascertained. Commoner tumour types were further analysed by invasive size. The significance of differences was established using the Chi-square test. RESULTS: 1137 tumours constituted the study group. The proportion of tumours with Emean below 50 kPa was higher in tubular cancers (23%) compared to ductal carcinomas of no specific type (DNST) (6%) (p < 0.001). Emax below 80 kPa was seen in 34% of tubular cancers compared to 16% of DNST (p < 0.002). Emean and Emax for lobular, mucinous, papillary and metaplastic cancers were not different from those of DNST. There were no significant differences in Emean or Emax between tumour types once broken down according to invasive size. CONCLUSIONS: Most breast cancer histological types have similar SWE characteristics. The exception is tubular cancer which has significantly lower stiffness than other histologic types, accounted for largely by their small size.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Técnicas de Imagem por Elasticidade , Ultrassonografia Mamária , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia com Agulha de Grande Calibre , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
10.
Vaccine ; 26(19): 2433-42, 2008 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-18423805

RESUMO

The paper explores the low uptake of livestock vaccination among poor farming communities in Bolivia utilising core elements of the original innovation diffusion theory. Contrary to the recent literature, we found that vaccination behaviour was strongly linked to social and cultural, rather than economic, drivers. While membership in a group increased uptake, the 'hot' and 'cold' distinctions which dictate health versus illness within Andean cosmology also played a role, with vaccination viewed as a means of addressing underlying imbalances. We concluded that uptake of livestock vaccination was unlikely to improve without knowledge transfer that acknowledges local epistemologies for livestock disease.


Assuntos
Animais Domésticos/imunologia , Difusão de Inovações , Vacinas/imunologia , Animais , Bolívia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , População Rural , Fatores Socioeconômicos
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