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1.
Hernia ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874659

RESUMO

PURPOSE: To investigate the differences in the visibility and size of abdominal wall hernias in computed tomography (CT) with and without Valsalva maneuver. METHODS: This single-center retrospective study included consecutive patients who underwent abdominal CTs with Valsalva maneuver between January 2018 and January 2022. Inclusion criteria was availability of an additional non-Valsalva CT within 6 months. A combined reference standard including clinical and surgical findings was used. Two independent, blinded radiologists measured the hernia sac size and rated hernia visibility on CTs with and without Valsalva. Differences were tested with a Wilcoxon signed rank test and McNemar's test. RESULTS: The final population included 95 patients (16 women; mean age 46 ± 11.6 years) with 205 hernias. Median hernia sac size on Valsalva CT was 31 mm compared with 24 mm on non-Valsalva CT (p < 0.001). In 73 and 82% of cases, the hernias were better visible on CT with Valsalva as compared to that without. 14 and 17% of hernias were only visible on the Valsalva CT. Hernia visibility on non-Valsalva CT varied according to subtype, with only 0 and 3% of umbilical hernias not being visible compared with 43% of femoral hernias. CONCLUSIONS: Abdominal wall hernias are larger and better visible on Valsalva CT compared with non-Valsalva CT in a significant proportion of patients and some hernias are only visible on the Valsalva CT. Therefore, this method should be preferred for the evaluation of abdominal wall hernias.

2.
Rev Esp Anestesiol Reanim (Engl Ed) ; 68(5): 245-251, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34140123

RESUMO

BACKGROUND: Propofol effect-site time course models included in TCI systems have been under discussion. We hypothesized that the rate of administration is a major contributor affecting the construction of a useful effect-site model: yielding different plasmatic concentrations, loss of consciousness may occur by different mechanisms more complex than the pharmacological effect-site. METHODOLOGY: ASA III patients were randomized in two groups: rapid induction (RI) received TCI of propofol effect-site (CeCALC) 5.4 µg/mL (modified Marsh model), and slow induction (SI) propofol infusion of 10 mg/kg/hour. A neurologist, blinded to induction method, performed neurological assessments using the FOUR score until the loss of consciousness (LOC). At LOC, the presence of brain stem reflexes, EEG index (PSI) and infusion time/mass of drug were registered. Fisher's exact test was used to describe differences between brain stem reflexes and respiration components of the FOUR score and CeCALC for 4 propofo models at LOC time. RESULTS: 16 patients divided in two groups were included. All patient in SI had brainstem reflexes free at LOC. In the RI, all patients had brain stem reflexes abolished and 1 patient had B and R of 4 points in the FOUR score (brain stem reflexes unaffected; P < .001). CeCALC at LOC time were contradictory at LOC in both groups and using 4 different Pk/Pd models. CONCLUSIONS: Depending of the infusion rate, propofol CeCALC at LOC calculated by different Pk/Pd models could be the source of confuse data to be used to guide the state of general anesthesia.


Assuntos
Propofol , Anestesia Geral , Anestésicos Intravenosos , Humanos , Inconsciência/induzido quimicamente
3.
Rev Esp Anestesiol Reanim (Engl Ed) ; 68(5): 245-251, 2021 05.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-33478749

RESUMO

BACKGROUND: Propofol effect-site time course models included in TCI systems have been under discussion. We hypothesized that the rate of administration is a major contributor affecting the construction of a useful effect-site model: yielding different plasmatic concentrations, loss of consciousness may occur by different mechanisms more complex than the pharmacological effect-site. METHODOLOGY: ASA I-II patients were randomized in two groups: rapid induction (RI) received TCI of propofol effect-site (CeCALC) 5.4µg/mL (modified Marsh model), and slow induction (SI) propofol infusion of 10mg/kg/hour. A neurologist, blinded to induction method, performed neurological assessments using the FOUR score until the loss of consciousness (LOC). At LOC, the presence of brain stem reflexes, EEG index (PSI) and infusion time/mass of drug were registered. Fisher's exact test was used to describe differences between brain stem reflexes and respiration components of the FOUR score and CeCALC for 4 propofol models at LOC time. RESULTS: 16 patients divided in two groups were included. All patient in SI had brainstem reflexes free at LOC. In the RI, all patients had brain stem reflexes abolished and 1 patient had B and R of 4 points in the FOUR score (brain stem reflexes unaffected; P<.001). CeCALC at LOC time were contradictory at LOC in both groups and using 4 different Pk/Pd models. CONCLUSIONS: Depending of the infusion rate, propofol CeCALC at LOC calculated by different Pk/Pd models could be the source of confuse data to be used to guide the state of general anesthesia.

6.
Rev Pneumol Clin ; 73(6): 290-293, 2017 Dec.
Artigo em Francês | MEDLINE | ID: mdl-29122396

RESUMO

Cannabis use has increased over the last decade. At the same time, we see cannabis allergies appearing, ranging from simple rhinoconjunctivitis to anaphylactic-type reactions, some of which are severe since fatal cases have been described, but we also see allergic-induced food allergies cross-linked in the family of lipid transfer proteins (LTP). Indeed, cannabis contains an LTP called Can s 3. The LT are very widespread in the vegetable kingdom and are present in many vegetables and fruits. LTPs have a similar chemical structure and therefore cross-allergy is common. Thus, by becoming aware of the LTP of cannabis, it is possible to become allergic by a mechanism of cross-allergy to the other LTPs present in fruits and vegetables. This syndrome is referred to as cannabis-fruit-vegetable syndrome.


Assuntos
Cannabis/imunologia , Hipersensibilidade Alimentar/imunologia , Alérgenos/imunologia , Proteínas de Transporte/imunologia , Reações Cruzadas/imunologia , Humanos
7.
Rehabilitation (Stuttg) ; 55(4): 238-47, 2016 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-27529301

RESUMO

The Federal German Pension Insurance in cooperation with professional organisations developed a curriculum for further socio-medical education of psychologists/psychotherapists, occupational therapists, physiotherapists, sports therapists and social workers/social pedagogues involved in medical rehabilitation. This curriculum aims to improve the professional competence of the therapeutic groups named above with regards to their contributions to the socio-medical capacity evaluation and related communication within the rehabilitation team. The curriculum was implemented for the first time in 2013. Using the results of the usibility evaluation the continued education concept was revised and manualised. The manual allows for a wide dissemination of the education concept.


Assuntos
Currículo , Educação Médica Continuada/organização & administração , Avaliação Educacional , Equipe de Assistência ao Paciente/organização & administração , Medicina Social/educação , Alemanha
9.
J R Soc Interface ; 12(110): 0509, 2015 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-26269233

RESUMO

This work aimed to develop novel composite biomaterials for bone tissue engineering (BTE) made of bioactive glass nanoparticles (Nbg) and alginate cross-linked with Cu(2+) or Ca(2+) (AlgNbgCu, AlgNbgCa, respectively). Two-dimensional scaffolds were prepared and the nanocomposite biomaterials were characterized in terms of morphology, mechanical strength, bioactivity, biodegradability, swelling capacity, release profile of the cross-linking cations and angiogenic properties. It was found that both Cu(2+) and Ca(2+) are released in a controlled and sustained manner with no burst release observed. Finally, in vitro results indicated that the bioactive ions released from both nanocomposite biomaterials were able to stimulate the differentiation of rat bone marrow-derived mesenchymal stem cells towards the osteogenic lineage. In addition, the typical endothelial cell property of forming tubes in Matrigel was observed for human umbilical vein endothelial cells when in contact with the novel biomaterials, particularly AlgNbgCu, which indicates their angiogenic properties. Hence, novel nanocomposite biomaterials made of Nbg and alginate cross-linked with Cu(2+) or Ca(2+) were developed with potential applications for preparation of multifunctional scaffolds for BTE.


Assuntos
Cálcio , Cobre , Células Endoteliais da Veia Umbilical Humana/metabolismo , Células-Tronco Mesenquimais/metabolismo , Nanocompostos/química , Engenharia Tecidual , Alicerces Teciduais/química , Animais , Substitutos Ósseos/química , Substitutos Ósseos/farmacocinética , Cálcio/química , Cálcio/farmacocinética , Cobre/química , Cobre/farmacocinética , Células Endoteliais da Veia Umbilical Humana/citologia , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Ratos , Ratos Sprague-Dawley
10.
Comput Med Imaging Graph ; 43: 64-77, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25841182

RESUMO

Proliferative diabetic retinopathy (PDR) is a condition that carries a high risk of severe visual impairment. The hallmark of PDR is the growth of abnormal new vessels. In this paper, an automated method for the detection of new vessels from retinal images is presented. This method is based on a dual classification approach. Two vessel segmentation approaches are applied to create two separate binary vessel map which each hold vital information. Local morphology features are measured from each binary vessel map to produce two separate 4-D feature vectors. Independent classification is performed for each feature vector using a support vector machine (SVM) classifier. The system then combines these individual outcomes to produce a final decision. This is followed by the creation of additional features to generate 21-D feature vectors, which feed into a genetic algorithm based feature selection approach with the objective of finding feature subsets that improve the performance of the classification. Sensitivity and specificity results using a dataset of 60 images are 0.9138 and 0.9600, respectively, on a per patch basis and 1.000 and 0.975, respectively, on a per image basis.


Assuntos
Algoritmos , Retinopatia Diabética/diagnóstico , Diagnóstico por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Retinopatia Diabética/genética , Humanos , Sensibilidade e Especificidade , Máquina de Vetores de Suporte
11.
J Cancer Educ ; 30(2): 340-3, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25056420

RESUMO

About half of all patients with cancer use complementary or alternative medicine (CAM). In 2013, we started a lecture program for patients, followed by evidence-based recommendations on counseling on CAM. These recommendations have been published before by this working group. The aim of the program is to provide scientific facts on the most often used CAM methods in standardized presentations which help patients discuss the topic with their oncologists and support shared decision making. The article presents the evaluation of the pilot phase. Participants received a standardized questionnaire before the start of the lecture. The questionnaire comprises four parts: demographic data, data concerning experience with CAM, satisfaction with the lecture, and needs for further information on CAM. In 2013, seven lectures on CAM were given in cooperation with regional branches of the German Cancer Society in several German states. Four hundred sixty patients and relatives took part (75% females and 16% males). Forty-eight percent formerly had used CAM. Most often named sources of information on CAM were print media (48%) and the Internet (37%). Most participants rated additional written information valuable. About one third would like to have an individual consultation concerning CAM. A standardized presentation of evidence on CAM methods most often used, together with recommendations on the self-management of symptoms, is highly appreciated. The concept of a highly interactive lecture comprising is feasible and if presented in lay terminology, adequate. In order to give additional support on the topic, written information should be provided as the first step.


Assuntos
Terapias Complementares/estatística & dados numéricos , Tomada de Decisões , Conhecimentos, Atitudes e Prática em Saúde , Neoplasias/terapia , Educação de Pacientes como Assunto , Pacientes/psicologia , Adulto , Idoso , Terapias Complementares/psicologia , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Projetos Piloto , Qualidade de Vida
12.
Comput Methods Programs Biomed ; 114(3): 247-61, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24636803

RESUMO

Proliferative diabetic retinopathy (PDR) is a condition that carries a high risk of severe visual impairment. The hallmark of PDR is neovascularisation, the growth of abnormal new vessels. This paper describes an automated method for the detection of new vessels in retinal images. Two vessel segmentation approaches are applied, using the standard line operator and a novel modified line operator. The latter is designed to reduce false responses to non-vessel edges. Both generated binary vessel maps hold vital information which must be processed separately. This is achieved with a dual classification system. Local morphology features are measured from each binary vessel map to produce two separate feature sets. Independent classification is performed for each feature set using a support vector machine (SVM) classifier. The system then combines these individual classification outcomes to produce a final decision. Sensitivity and specificity results using a dataset of 60 images are 0.862 and 0.944 respectively on a per patch basis and 1.00 and 0.90 respectively on a per image basis.


Assuntos
Retinopatia Diabética/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Neovascularização Patológica , Retina/fisiologia , Algoritmos , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Disco Óptico/fisiologia , Reconhecimento Automatizado de Padrão/métodos , Vasos Retinianos/anatomia & histologia , Sensibilidade e Especificidade , Máquina de Vetores de Suporte
13.
Comput Med Imaging Graph ; 37(1): 48-60, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23410507

RESUMO

Changes and variation in retinal vessel width are related to vascular risk factors and prospectively related to cardiovascular disease in later life. Hence, assessment of vessel width may be a useful physio-marker and potential predictor of cardiovascular status. However, measurement of vessel calibre from retinal images is a challenging process to automate. This paper proposes an automated system to measure vessel calibre in retinal images, which is demonstrated in images of multi-ethnic school children. The diameter measurement is based on the detection of the centreline pixels from a vessel probability map image, determining the vessel orientation at these pixels, extracting the vessel segments and later using a two-dimensional model, which is optimized to fit various types of intensity profiles of vessel segments. The width is then estimated from parameters of the optimized model. The method is also quantitatively analyzed using monochromatic representations of different colour spaces. The algorithm is evaluated on a recently introduced public database CHASE_DB1, which is a subset of retinal images of multi-ethnic children from the Child Heart and Health Study in England (CHASE) dataset. Moreover, the precise estimation of retinal vascular widths is critical for epidemiologists to identify the risk factors. This work also introduces an interactive software tool for epidemiologists, with which retinal vessel calibre can be precisely marked.


Assuntos
Etnicidade , Oftalmoscopia/métodos , Reconhecimento Automatizado de Padrão/métodos , Vasos Retinianos/anatomia & histologia , Algoritmos , Criança , Inglaterra , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Fatores de Risco , Software , Inquéritos e Questionários
14.
Comput Methods Programs Biomed ; 108(1): 407-33, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22525589

RESUMO

Retinal vessel segmentation algorithms are a fundamental component of automatic retinal disease screening systems. This work examines the blood vessel segmentation methodologies in two dimensional retinal images acquired from a fundus camera and a survey of techniques is presented. The aim of this paper is to review, analyze and categorize the retinal vessel extraction algorithms, techniques and methodologies, giving a brief description, highlighting the key points and the performance measures. We intend to give the reader a framework for the existing research; to introduce the range of retinal vessel segmentation algorithms; to discuss the current trends and future directions and summarize the open problems. The performance of algorithms is compared and analyzed on two publicly available databases (DRIVE and STARE) of retinal images using a number of measures which include accuracy, true positive rate, false positive rate, sensitivity, specificity and area under receiver operating characteristic (ROC) curve.


Assuntos
Vasos Sanguíneos/patologia , Algoritmos , Fundo de Olho , Humanos
15.
Pharmacopsychiatry ; 45(4): 156-61, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22290202

RESUMO

OBJECTIVE: The aim of this study was to estimate the potential bias by personality traits for ratings on the Positive and Negative Syndrome Scale (PANSS). METHODS: Personality dimensions (five factor model), personality traits (SCID-II) and PANSS scores were assessed prospectively in 45 patients with schizophrenia spectrum disorders (SSD). RESULTS: Borderline (r=0.34; p=0.021), avoidant (r=0.66; p<0.001) and depressive (r=0.51; p<0.001) personality traits were significantly correlated with the PANSS total score. There were significant correlations for all PANSS subscores with the exemption of PANSS positive. In multivariate analyses, the final models for PANSS total score and PANSS depressive explained a total of 45.3% and 54.3% of the variance. Avoidant traits could lead to a difference of 13.1 (95% CI: 5.6-20.7) points regarding PANSS total score, depressive traits could cause differences of 4.8 points (95% CI: 2.2-7.3) for PANSS depressive subscore. CONCLUSION: Although PANSS positive subscore and PANSS excited component are relatively robust against bias by personality traits, PANSS total score and the remaining subscores are affected to a clinically relevant degree. Outcome studies in SSD patients should control for personality traits.


Assuntos
Viés , Transtornos da Personalidade/diagnóstico , Transtornos da Personalidade/etiologia , Escalas de Graduação Psiquiátrica , Esquizofrenia/complicações , Psicologia do Esquizofrênico , Adulto , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Inventário de Personalidade , Esquizofrenia/diagnóstico , Adulto Jovem
16.
Comput Methods Programs Biomed ; 108(2): 600-16, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21963241

RESUMO

The change in morphology, diameter, branching pattern or tortuosity of retinal blood vessels is an important indicator of various clinical disorders of the eye and the body. This paper reports an automated method for segmentation of blood vessels in retinal images. A unique combination of techniques for vessel centerlines detection and morphological bit plane slicing is presented to extract the blood vessel tree from the retinal images. The centerlines are extracted by using the first order derivative of a Gaussian filter in four orientations and then evaluation of derivative signs and average derivative values is performed. Mathematical morphology has emerged as a proficient technique for quantifying the blood vessels in the retina. The shape and orientation map of blood vessels is obtained by applying a multidirectional morphological top-hat operator with a linear structuring element followed by bit plane slicing of the vessel enhanced grayscale image. The centerlines are combined with these maps to obtain the segmented vessel tree. The methodology is tested on three publicly available databases DRIVE, STARE and MESSIDOR. The results demonstrate that the performance of the proposed algorithm is comparable with state of the art techniques in terms of accuracy, sensitivity and specificity.


Assuntos
Vasos Retinianos/anatomia & histologia , Humanos
17.
Neurology ; 76(1): 62-8, 2011 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-21205696

RESUMO

BACKGROUND: The NIH Stroke Scale (NIHSS) is used to assess acute ischemic stroke severity and outcome. High NIHSS scores are usually associated with arterial occlusion but it is unknown what the effect of time to clinical evaluation (TTCE) in this association is. We tested the NIHSS scores as an instrument to determine vessel occlusion (VO) at different time points from symptom onset. METHODS: Patients were selected from our prospective stroke database if they had admission NIHSS scores and intracranial vessel neuroimaging studies. We dichotomized patients according to VO and TTCE. Receiver operating curves, c statistics, and odds ratios were calculated to study the validity of the NIHSS score. RESULTS: Among 463 patients (mean age 70.2 years, 53.1% male, median NIHSS 4, median TTCE 3.3 hours), 22.5% had arterial occlusion. Median NIHSS scores were higher in patients with VO, 10.5 (interquartile range 5-18) vs 3 (2-7), p<0.001, and in those with TTCE<6 hours, 15 (interquartile range 7-19) vs 4 (2-8) if ≥6 hours, p<0.001. Receiver operating characteristic curves showed that the validity of NIHSS in predicting VO was higher in patients with TTCE<6 hours, p=0.03. The best cutoff point in patients evaluated before 6 hours was an NIHSS of 7 (76.2% sensitivity, specificity 70.1%), while in patients evaluated after 6 hours the best cutoff point was 4 (sensitivity 65.4%, specificity 62.0%). CONCLUSIONS: Our study shows that the validity of NIHSS scores in predicting arterial occlusion is time-dependent, decreasing with increasing time from symptom onset to clinical evaluation.


Assuntos
Arteriopatias Oclusivas/diagnóstico , Arteriopatias Oclusivas/etiologia , Infarto Cerebral/complicações , Índice de Gravidade de Doença , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Angiografia por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , National Institutes of Health (U.S.) , Exame Neurológico , Valor Preditivo dos Testes , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Estatísticas não Paramétricas , Fatores de Tempo , Tomógrafos Computadorizados , Ultrassonografia Doppler Transcraniana , Estados Unidos
18.
Klin Padiatr ; 221(3): 141-9, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19437361

RESUMO

The present paper outlines the initial version of the ACGT (Advancing Clinico-Genomic Trials) -- an Integrated Project, partly funded by the EC (FP6-2005-IST-026996)I-Oncosimulator as an integrated software system simulating in vivo tumour response to therapeutic modalities within the clinical trials environment aiming to support clinical decision making in individual patients. Cancer treatment optimization is the main goal of the system. The document refers to the technology of the system and the clinical requirements and the types of medical data needed for exploitation in the case of nephroblastoma. The outcome of an initial step towards the clinical adaptation and validation of the system is presented and discussed. Use of anonymized real data before and after chemotherapeutic treatment for the case of the SIOP 2001/GPOH nephroblastoma clinical trial constitutes the basis of the clinical adaptation and validation process. By using real medical data concerning nephroblastoma for a single patient in conjunction with plausible values for the model parameters (based on available literature) a reasonable prediction of the actual tumour volume shrinkage has been made possible. Obviously as more and more sets of medical data are exploited the reliability of the model "tuning" is expected to increase. The successful performance of the initial combined ACGT Oncosimulator platform, although usable up to now only as a test of principle, has been a particularly encouraging step towards the clinical translation of the system, being the first of its kind worldwide.


Assuntos
Simulação por Computador , Técnicas de Apoio para a Decisão , Neoplasias Renais/tratamento farmacológico , Terapia Neoadjuvante , Software , Tumor de Wilms/tratamento farmacológico , Algoritmos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Criança , Teoria dos Jogos , Humanos , Imageamento Tridimensional , Rim/patologia , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Modelos Teóricos , Resultado do Tratamento , Carga Tumoral , Tumor de Wilms/patologia , Tumor de Wilms/cirurgia
19.
Exp Cell Res ; 314(7): 1455-64, 2008 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-18314101

RESUMO

In early pregnancy, fetal trophoblasts selectively invade and remodel maternal spiral arteries. A healthy pregnancy is dependent on this adaptation to allow sufficient maternal blood to reach the placenta and the developing fetus. However, little is known of the role played by trophoblasts in this adaptation process. In this study, the interactions between trophoblast cells (TC) and vascular smooth muscle cells (VSMC) were examined using novel live cell image analysis methods which allow quantitative assessment of the behaviour of these two cell types in co-culture. TC and VSMC were simultaneously tracked in co-culture and, for each cell type, directionality, speed and the cell-cell interaction were assessed. The overall migratory behaviour of TC was markedly different in the presence of VSMC with co-cultured TC migrating further with directional movement while mono-cultured TC moved more randomly. Furthermore, TC were shown to specifically target VSMC, suggesting that invading TC may initiate targeted vascular remodelling. Analysis of movement behaviour and cell-cell attraction will be useful in other co-culture systems in addition to answering important questions in the reproductive field.


Assuntos
Comunicação Celular , Feto/citologia , Imageamento Tridimensional , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Trofoblastos/citologia , Fenômenos Biomecânicos , Movimento Celular , Sobrevivência Celular , Técnicas de Cocultura , Feminino , Humanos , Especificidade de Órgãos , Gravidez , Reprodutibilidade dos Testes , Fatores de Tempo
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