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1.
Reg Anesth Pain Med ; 47(12): 744-748, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36283712

RESUMO

INTRODUCTION: Caudal block is frequently performed to provide analgesia for hypospadias repair. Literature suggests that pudendal block provides prolonged postoperative analgesia as compared with caudal block in children between 2 and 5 years. We compared the efficacy of pudendal and caudal blocks in children less than 2 years. METHODS: 60 children scheduled for hypospadias repair received standard general anesthesia along with either pudendal or caudal block (groups of 30 each). Variables collected were demographic data, block time, operating room time, intraoperative pain medication need, pain assessment score and medication need in the recovery room and pain assessment at home. RESULT: Groups were demographically similar. No differences were observed in the following recorded times (minutes): block procedure (caudal: 9.5±4.0, pudendal: 10.6±4.1, p=0.30), anesthesia (caudal: 17.3±5.3, pudendal: 17.7±4.3, p=0.75), total OR (caudal: 171±35, pudendal: 172±41; p=0.95) and postanesthesia care unit (PACU) stay (caudal: 88±37, pudendal: 86±42; p=0.80). Additionally, no differences were observed in rescue pain medication need in the operating room (caudal: 0, pudendal: 2 (p=0.49), in PACU (caudal: 4, pudendal: 4, p=0.99), pain assessed at home, time to pain level 2 (caudal: 13.93±8.9, pudendal: 15.17±8.7), average pain scores (p=0.67) and total pain free epochs (pain level of zero) (p=0.80) in the first 24 hours. DISCUSSION: In children less than 2 years, both blocks provide comparable intraoperative and postoperative pain relief in the first 24 hours after hypospadias surgery. TRIAL REGISTRATION NUMBER: NCT03145415.


Assuntos
Hipospadia , Bloqueio Nervoso , Nervo Pudendo , Criança , Masculino , Humanos , Pré-Escolar , Hipospadia/diagnóstico , Hipospadia/cirurgia , Bloqueio Nervoso/efeitos adversos , Bloqueio Nervoso/métodos , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/etiologia , Dor Pós-Operatória/prevenção & controle , Estudos Prospectivos
2.
Urol Case Rep ; 40: 101873, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34660205

RESUMO

Intratesticular abscess is a rare finding associated with advanced or untreated epididymo-orchitis, often in immunocompromised patients. Implicated pathogens can be spread hematogenously, by urine reflux in dysfunctional voiders, through aberrant mesonephric duct anatomy, or via a patent processus vaginalis in the setting of an intra-abdominal infection. A testicular-sparing surgical approach is often used in prepubertal populations and is associated with positive outcomes. We present the case of a 6-year-old male with a polymicrobial intratesticular abscess that was successfully managed with antibiotics, operative incision and drainage of abscess cavity, and primary wound closure with drain placement.

3.
Brain Sci ; 11(7)2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34356169

RESUMO

The effect of stress on task performance is complex, too much or too little stress negatively affects performance and there exists an optimal level of stress to drive optimal performance. Task difficulty and external affective factors are distinct stressors that impact cognitive performance. Neuroimaging studies showed that mood affects working memory performance and the correlates are changes in haemodynamic activity in the prefrontal cortex (PFC). We investigate the interactive effects of affective states and working memory load (WML) on working memory task performance and haemodynamic activity using functional near-infrared spectroscopy (fNIRS) neuroimaging on the PFC of healthy participants. We seek to understand if haemodynamic responses could tell apart workload-related stress from situational stress arising from external affective distraction. We found that the haemodynamic changes towards affective stressor- and workload-related stress were more dominant in the medial and lateral PFC, respectively. Our study reveals distinct affective state-dependent modulations of haemodynamic activity with increasing WML in n-back tasks, which correlate with decreasing performance. The influence of a negative effect on performance is greater at higher WML, and haemodynamic activity showed evident changes in temporal, and both spatial and strength of activation differently with WML.

4.
IEEE J Biomed Health Inform ; 22(4): 1148-1156, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-28692996

RESUMO

Near-infrared spectroscopy (NIRS), one of the candidates to be used in a neurofeedback system or brain-computer interface (BCI), measures the brain activity by monitoring the changes in cerebral hemoglobin concentration. However, hemodynamic changes in the scalp may affect the NIRS signals. In order to remove the superficial signals when NIRS is used in a neurofeedback system or BCI, real-time processing is necessary. Real-time scalp signal separating (RT-SSS) algorithm, which is capable of separating the scalp-blood signals from NIRS signals obtained in real-time, may thus be applied. To demonstrate its effectiveness, two separate neurofeedback experiments were conducted. In the first experiment, the feedback signal was the raw NIRS signal recorded while in the second experiment, deep signal extracted using RT-SSS algorithm was used as the feedback signal. In both experiments, participants were instructed to control the feedback signal to follow a predefined track. Accuracy scores were calculated based on the differences between the trace controlled by feedback signal and the targeted track. Overall, the second experiment yielded better performance in terms of accuracy scores. These findings proved that RT-SSS algorithm is beneficial for neurofeedback.


Assuntos
Algoritmos , Neurorretroalimentação/métodos , Couro Cabeludo/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Adulto , Encéfalo/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador
5.
Comput Biol Med ; 88: 110-125, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28711767

RESUMO

Knee osteoarthritis (OA) progression can be monitored by measuring changes in the subchondral bone structure such as area and shape from MR images as an imaging biomarker. However, measurements of these minute changes are highly dependent on the accurate segmentation of bone tissue from MR images and it is challenging task due to the complex tissue structure and inadequate image contrast/brightness. In this paper, a fully automated method for segmenting subchondral bone from knee MR images is proposed. Here, the contrast of knee MR images is enhanced using a gray-level S-curve transformation followed by automatic seed point detection using a three-dimensional multi-edge overlapping technique. Successively, bone regions are initially extracted using distance-regularized level-set evolution followed by identification and correction of leakages along the bone boundary regions using a boundary displacement technique. The performance of the developed technique is evaluated against ground truths by measuring sensitivity, specificity, dice similarity coefficient (DSC), average surface distance (AvgD) and root mean square surface distance (RMSD). An average sensitivity (91.14%), specificity (99.12%) and DSC (90.28%) with 95% confidence interval (CI) in the range 89.74-92.54%, 98.93-99.31% and 88.68-91.88% respectively is achieved for the femur bone segmentation in 8 datasets. For tibia bone, average sensitivity (90.69%), specificity (99.65%) and DSC (91.35%) with 95% CI in the range 88.59-92.79%, 99.50-99.80% and 88.68-91.88% respectively is achieved. AvgD and RMSD values for femur are 1.43 ± 0.23 (mm) and 2.10 ± 0.35 (mm) respectively while for tibia, the values are 0.95 ± 0.28 (mm) and 1.30 ± 0.42 (mm) respectively that demonstrates acceptable error between proposed method and ground truths. In conclusion, results obtained in this work demonstrate substantially significant performance with consistency and robustness that led the proposed method to be applicable for large scale and longitudinal knee OA studies in clinical settings.


Assuntos
Imageamento Tridimensional/métodos , Joelho/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Algoritmos , Humanos , Osteoartrite do Joelho/diagnóstico por imagem
6.
Comput Biol Med ; 83: 120-133, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28279861

RESUMO

Most medical images suffer from inadequate contrast and brightness, which leads to blurred or weak edges (low contrast) between adjacent tissues resulting in poor segmentation and errors in classification of tissues. Thus, contrast enhancement to improve visual information is extremely important in the development of computational approaches for obtaining quantitative measurements from medical images. In this research, a contrast enhancement algorithm that applies gray-level S-curve transformation technique locally in medical images obtained from various modalities is investigated. The S-curve transformation is an extended gray level transformation technique that results into a curve similar to a sigmoid function through a pixel to pixel transformation. This curve essentially increases the difference between minimum and maximum gray values and the image gradient, locally thereby, strengthening edges between adjacent tissues. The performance of the proposed technique is determined by measuring several parameters namely, edge content (improvement in image gradient), enhancement measure (degree of contrast enhancement), absolute mean brightness error (luminance distortion caused by the enhancement), and feature similarity index measure (preservation of the original image features). Based on medical image datasets comprising 1937 images from various modalities such as ultrasound, mammograms, fluorescent images, fundus, X-ray radiographs and MR images, it is found that the local gray-level S-curve transformation outperforms existing techniques in terms of improved contrast and brightness, resulting in clear and strong edges between adjacent tissues. The proposed technique can be used as a preprocessing tool for effective segmentation and classification of tissue structures in medical images.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Biomed Opt Express ; 7(10): 3882-3898, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27867700

RESUMO

Previous studies reported mental stress as one of the major contributing factors leading to various diseases such as heart attack, depression and stroke. An accurate stress assessment method may thus be of importance to clinical intervention and disease prevention. We propose a joint independent component analysis (jICA) based approach to fuse simultaneous measurement of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) on the prefrontal cortex (PFC) as a means of stress assessment. For the purpose of this study, stress was induced by using an established mental arithmetic task under time pressure with negative feedback. The induction of mental stress was confirmed by salivary alpha amylase test. Experiment results showed that the proposed fusion of EEG and fNIRS measurements improves the classification accuracy of mental stress by +3.4% compared to EEG alone and +11% compared to fNIRS alone. Similar improvements were also observed in sensitivity and specificity of proposed approach over unimodal EEG/fNIRS. Our study suggests that combination of EEG (frontal alpha rhythm) and fNIRS (concentration change of oxygenated hemoglobin) could be a potential means to assess mental stress objectively.

8.
J Biol Chem ; 291(5): 2119-35, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26655722

RESUMO

The expansion of fat mass in the obese state is due to increased adipocyte hypertrophy and hyperplasia. The molecular mechanism that drives adipocyte hyperplasia remains unknown. The NAD(+)-dependent protein deacetylase sirtuin 1 (SIRT1), a key regulator of mammalian metabolism, maintains proper metabolic functions in many tissues, counteracting obesity. Here we report that differentiated adipocytes are hyperplastic when SIRT1 is knocked down stably in mouse 3T3-L1 preadipocytes. This phenotype is associated with dysregulated adipocyte metabolism and enhanced inflammation. We also demonstrate that SIRT1 is a key regulator of proliferation in preadipocytes. Quantitative proteomics reveal that the c-Myc pathway is altered to drive enhanced proliferation in SIRT1-silenced 3T3-L1 cells. Moreover, c-Myc is hyperacetylated, levels of p27 are reduced, and cyclin-dependent kinase 2 (CDK2) is activated upon SIRT1 reduction. Remarkably, differentiating SIRT1-silenced preadipocytes exhibit enhanced mitotic clonal expansion accompanied by reduced levels of p27 as well as elevated levels of CCAAT/enhancer-binding protein ß (C/EBPß) and c-Myc, which is also hyperacetylated. c-Myc activation and enhanced proliferation phenotype are also found to be SIRT1-dependent in proliferating mouse embryonic fibroblasts and differentiating human SW872 preadipocytes. Reducing both SIRT1 and c-Myc expression in 3T3-L1 cells simultaneously does not induce the adipocyte hyperplasia phenotype, confirming that SIRT1 controls adipocyte hyperplasia through c-Myc regulation. A better understanding of the molecular mechanisms of adipocyte hyperplasia will open new avenues toward understanding obesity.


Assuntos
Adipócitos/metabolismo , Regulação da Expressão Gênica , Hiperplasia/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Sirtuína 1/metabolismo , Células 3T3-L1 , Adipócitos/citologia , Animais , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Diferenciação Celular , Proliferação de Células , Fibroblastos/metabolismo , Inativação Gênica , Células HEK293 , Humanos , Hipertrofia/metabolismo , Inflamação , Camundongos , Obesidade/metabolismo , Proteômica
9.
Australas J Dermatol ; 56(4): 285-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25367709

RESUMO

An objective tool to quantify treatment response in vitiligo is currently lacking. This study aimed to objectively evaluate the treatment response in vitiligo by using a computerised digital imaging analysis system (C-DIAS) and to compare it with the physician's global assessment (PGA). Tacrolimus ointment 0.1% (Protopic; Astellas Pharma Tech,Toyama, Japan) was applied twice daily on selected lesions which were photographed every 6 weeks for 24 weeks. The primary efficacy end-point was the mean percentage of repigmentation (MPR), as assessed by the digital method (MPR-C-DIAS) or by the PGA. The response was categorised into none (0%), mild (1-25%), moderate (26-50%), good (51-75%) and excellent (76-100%). MPR-C-DIAS: Out of 56 patients, 44 (79%) responded. Overall, the response was mild in 22 (39%), moderate in 21(40%) and good in one (2%) patient(s). A total of 39 (70%) patients responded as measured by PGA. The repigmentation was mild in 27(48%), moderate in 10 (18%) and good to excellent in two (4%) patients. The κ test of consistency was 0.17 (P = 0.053), which shows poor agreement between the two assessment methods, although this is not statistically significant. The C-DIAS can be used to perform an objective analysis of repigmentation or depigmentation in vitiligo skin lesions in response to treatment.


Assuntos
Processamento de Imagem Assistida por Computador , Imunossupressores/uso terapêutico , Tacrolimo/uso terapêutico , Vitiligo/diagnóstico por imagem , Vitiligo/tratamento farmacológico , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Pigmentação da Pele/efeitos dos fármacos , Resultado do Tratamento , Adulto Jovem
10.
Rheumatol Int ; 35(1): 1-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24879325

RESUMO

Early detection of knee osteoarthritis (OA) is of great interest to orthopaedic surgeons, rheumatologists, radiologists, and researchers because it would allow physicians to provide patients with treatments and advice to slow the onset or progression of the disease. Early detection can be achieved by identifying early changes in selected features of degenerative articular cartilage (AC) using non-invasive imaging modalities. Magnetic resonance imaging (MRI) is becoming the standard for assessment of OA. The aim of this paper was to review the influence of MRI on the selection, detection, and measurement of AC features associated with early OA. Our review of the literature indicates that the changes associated with early OA are in cartilage thickness, cartilage volume, cartilage water content, and proteoglycan content that can be accurately, consistently, and non-invasively measured using MRI. Choosing an MR pulse sequence that provides the capability to assess cartilage physiology and morphology in a single acquisition and advanced multi-nuclei MRI is desirable. The results of the review indicate that using an ultra-high magnetic strength, MR imager does not affect early OA detection. In conclusion, MRI is currently the most suitable modality for early detection of knee OA, and future research should focus on the quantitative evaluation of early OA features using advances in MR hardware, software, and data processing with sophisticated image/pattern recognition techniques.


Assuntos
Cartilagem Articular/patologia , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/patologia , Progressão da Doença , Humanos , Processamento de Imagem Assistida por Computador , Articulação do Joelho/patologia , Índice de Gravidade de Doença
11.
Acad Radiol ; 22(1): 93-104, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25481518

RESUMO

RATIONALE AND OBJECTIVES: Quantitative assessment of knee articular cartilage (AC) morphology using magnetic resonance (MR) imaging requires an accurate segmentation and 3D reconstruction. However, automatic AC segmentation and 3D reconstruction from hydrogen-based MR images alone is challenging because of inhomogeneous intensities, shape irregularity, and low contrast existing in the cartilage region. Thus, the objective of this research was to provide an insight into morphologic assessment of AC using multilevel data processing of multinuclear ((23)Na and (1)H) MR knee images. MATERIALS AND METHODS: A dual-tuned ((23)Na and (1)H) radio-frequency coil with 1.5-T MR scanner is used to scan four human subjects using two separate MR pulse sequences for the respective sodium and proton imaging of the knee. Postprocessing is performed using customized routines written in MATLAB. MR data were fused to improve contrast of the cartilage region that is further used for automatic segmentation. Marching cubes algorithm is applied on the segmented AC slices for 3D volume rendering and volume is then calculated using the divergence theorem. RESULTS: Fusion of multinuclear MR images results in an improved contrast (factor >3) in the cartilage region. Sensitivity (80.21%) and specificity (99.64%) analysis performed by comparing manually segmented AC shows a good performance of the automated AC segmentation. The average cartilage volume (23.19 ± 1.38 cm(3); coefficient of variation [COV] -0.059) measured from 3D AC models of four data sets shows a marked improvement over average cartilage volume (23.24 cm(3); COV -0.19) reported earlier. CONCLUSIONS: This study confirms the use of multinuclear MR data for cartilage morphology (volume) assessment that can be used in clinical settings.


Assuntos
Cartilagem Articular/anatomia & histologia , Cartilagem Articular/metabolismo , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/metabolismo , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Prótons por Ressonância Magnética/métodos , Sódio/metabolismo , Feminino , Humanos , Aumento da Imagem/métodos , Masculino , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Isótopos de Sódio/farmacocinética
12.
Artigo em Inglês | MEDLINE | ID: mdl-24111222

RESUMO

The onset of osteoarthritis (OA), a most common knee joint disease, can be characterized by the degeneration of articular cartilage (AC). Degenerative changes in AC have been assessed by the morphological and physiological measurements using non-invasive modality such as Magnetic Resonance Imaging (MRI) to obtain MRI images of the knee. However, visualization and quantification of AC from MR images is difficult due to the low visibility contrast of AC compared to surrounding tissues, low and varying signal intensities in cartilage region and variable intensities in different slices of single dataset. In this work, we present a method to fuse multinuclear ((23)Na and (1)H) MR images acquired in the same plane without changing the position of the human knee as well as the Radio Frequency (RF) coil. This work is performed towards our hypothesis that fusion of sodium and proton images will provide an enhanced image that can be used for an accurate assessment of cartilage morphology. Our result shows that merging of sodium knee MR image with proton knee MR image resulting in enhanced contrast information in the cartilage region and resolves low visibility and varying intensities issue with 2D/3D proton MR. We conclude that the proposed method can further be utilized for the accurate assessment of cartilage morphology.


Assuntos
Cartilagem Articular/patologia , Articulação do Joelho/patologia , Joelho/patologia , Imageamento por Ressonância Magnética , Osteoartrite do Joelho/patologia , Meios de Contraste , Humanos , Aumento da Imagem/métodos , Osteoartrite do Joelho/diagnóstico , Prótons , Ondas de Rádio , Vasos Retinianos/patologia , Sódio/química
13.
Magn Reson Imaging ; 31(7): 1059-67, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23731535

RESUMO

Osteoarthritis is a common joint disorder that is most prevalent in the knee joint. Knee osteoarthritis (OA) can be characterized by the gradual loss of articular cartilage (AC). Formation of lesion, fissures and cracks on the cartilage surface has been associated with degenerative AC and can be measured by morphological assessment. In addition, loss of proteoglycan from extracellular matrix of the AC can be measured at early stage of cartilage degradation by physiological assessment. In this case, a biochemical phenomenon of cartilage is used to assess the changes at early degeneration of AC. In this paper, a method to measure local sodium concentration in AC due to proteoglycan has been investigated. A clinical 1.5-T magnetic resonance imaging (MRI) with multinuclear spectroscopic facility is used to acquire sodium images and quantify local sodium content of AC. An optimised 3D gradient-echo sequence with low echo time has been used for MR scan. The estimated sodium concentration in AC region from four different data sets is found to be ~225±19mmol/l, which matches the values that has been reported for the normal AC. This study shows that sodium images acquired at clinical 1.5-T MRI system can generate an adequate quantitative data that enable the estimation of sodium concentration in AC. We conclude that this method is potentially suitable for non-invasive physiological (sodium content) measurement of articular cartilage.


Assuntos
Cartilagem Articular/patologia , Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/patologia , Sódio/química , Calibragem , Cartilagem/patologia , Desenho de Equipamento , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imagens de Fantasmas , Proteoglicanas/química
14.
Artigo em Inglês | MEDLINE | ID: mdl-23366902

RESUMO

Psoriasis is a common skin disorder with a prevalence of 0.6 - 4.8% around the world. The most common is plaques psoriasis and it appears as red scaling plaques. Psoriasis is incurable but treatable in a long term treatment. Although PASI (Psoriasis Area and Severity Index) scoring is recognised as gold standard for psoriasis assessment, this method is still influenced by inter and intra-rater variation. An imaging and analysis system called α-PASI is developed to perform PASI scoring objectively. Percentage of lesion area to the body surface area is one of PASI parameter. In this paper, enhanced imaging methods are developed to improve the determination of body surface area (BSA) and lesion area. BSA determination method has been validated on medical mannequin. BSA accuracies obtained at four body regions are 97.80% (lower limb), 92.41% (trunk), 87.72% (upper limb), and 83.82% (head). By applying fuzzy c-means clustering algorithm, the membership functions of lesions area for PASI area scoring have been determined. Performance of scoring result has been tested with double assessment by α-PASI area algorithm on body region images from 46 patients. Kappa coefficients for α-PASI system are greater than or equal to 0.72 for all body regions (Head - 0.76, Upper limb - 0.81, Trunk - 0.85, Lower limb - 0.72). The overall kappa coefficient for the α-PASI area is 0.80 that can be categorised as substantial agreement. This shows that the α-PASI area system has a high reliability and can be used in psoriasis area assessment.


Assuntos
Superfície Corporal , Dermoscopia/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Psoríase/patologia , Índice de Gravidade de Doença , Imagem Corporal Total/métodos , Algoritmos , Humanos , Aumento da Imagem/métodos , Imageamento Tridimensional/métodos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Skin Res Technol ; 18(1): 1-14, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21605170

RESUMO

INTRODUCTION: This paper presents a comprehensive review of acne grading and measurement. Acne is a chronic disorder of the pilosebaceous units, with excess sebum production, follicular epidermal hyperproliferation, inflammation and Propionibacterium acnes activity. Most patients are affected with acne vulgaris, which is the prevalent type of acne. Acne vulgaris consists of comedones (whitehead and blackhead), papules, pustules, nodules and cysts. OBJECTIVES: To review and identify the issues for acne vulgaris grading and computational assessment methods. To determine the future direction for addressing the identified issues. METHODS: There are two main methods of assessment for acne severity grading, namely, lesion counting and comparison of patient with a photographic standard. For the computational assessment method, the emphasis is on computational imaging techniques. RESULTS: Current acne grading methods are very time consuming and tedious. Generally, they rely on approximation for counting lesions and hence the assessment is quite subjective, with both inter and intra-observer variability. It is important to accurately assess acne grade to evaluate its severity as this influences treatment selection and assessment of response to therapy. This will further help in better disease management and more efficacious treatment. CONCLUSION: Semi-automated or automated methods based on computational imaging techniques should be devised for acne grade assessment.


Assuntos
Acne Vulgar/classificação , Acne Vulgar/diagnóstico , Dermoscopia/métodos , Interpretação de Imagem Assistida por Computador/métodos , Fotografação/métodos , Índice de Gravidade de Doença , Humanos
17.
IEEE Trans Biomed Eng ; 58(5): 1383-93, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21177154

RESUMO

A signal subspace approach for extracting visual evoked potentials (VEPs) from the background electroencephalogram (EEG) colored noise without the need for a prewhitening stage is proposed. Linear estimation of the clean signal is performed by minimizing signal distortion while maintaining the residual noise energy below some given threshold. The generalized eigendecomposition of the covariance matrices of a VEP signal and brain background EEG noise is used to transform them jointly to diagonal matrices. The generalized subspace is then decomposed into signal subspace and noise subspace. Enhancement is performed by nulling the components in the noise subspace and retaining the components in the signal subspace. The performance of the proposed algorithm is tested with simulated and real data, and compared with the recently proposed signal subspace techniques. With the simulated data, the algorithms are used to estimate the latencies of P(100), P(200), and P(300) of VEP signals corrupted by additive colored noise at different values of SNR. With the real data, the VEP signals are collected at Selayang Hospital, Kuala Lumpur, Malaysia, and the capability of the proposed algorithm in detecting the latency of P(100) is obtained and compared with other subspace techniques. The ensemble averaging technique is used as a baseline for this comparison. The results indicated significant improvement by the proposed technique in terms of better accuracy and less failure rate.


Assuntos
Eletroencefalografia/métodos , Potenciais Evocados Visuais/fisiologia , Processamento de Sinais Assistido por Computador , Algoritmos , Simulação por Computador , Humanos , Reprodutibilidade dos Testes
18.
Kidney Int ; 76(5): 500-11, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19536084

RESUMO

Ureteral obstruction results in renal fibrosis in part due to inflammatory injury. The role of interleukin-18 (IL-18), an important mediator of inflammation, in the genesis of renal fibrosis was studied using transgenic mice overexpressing human IL-18-binding protein. In addition, HK-2 cells were analyzed following direct exposure to IL-18 compared to control media. Two weeks after ureteral obstruction, the kidneys of wild-type mice had a significant increase in IL-18 production, collagen deposition, alpha-smooth muscle actin and RhoA expression, fibroblast and macrophage accumulation, chemokine expression, and transforming growth factor-beta1 (TGF-beta1) and tumor necrosis factor-alpha (TNF-alpha) production, whereas E-cadherin expression was simultaneously decreased. The transgenic mice with neutralized IL-18 activity exhibited significant reductions in these indicators of obstruction-induced renal fibrosis and epithelial- mesenchymal transition, without demonstrating alterations in TGF-beta1 or TNF-alpha activity. Similarly, the HK-2 cells exhibited increased alpha-smooth muscle actin expression and collagen production, and decreased E-cadherin expression in response to IL-18 stimulation without alterations in TNF-alpha or TGF-beta1 activity. Our study demonstrates that IL-18 is a significant mediator of obstruction-induced renal fibrosis and epithelial- mesenchymal transition independent of downstream TGF-beta1 or TNF-alpha production.


Assuntos
Células Epiteliais/patologia , Interleucina-18/fisiologia , Rim/patologia , Mesoderma/patologia , Actinas/análise , Animais , Linhagem Celular , Quimiocinas/genética , Colágeno/genética , Colágeno/metabolismo , Fibrose , Peptídeos e Proteínas de Sinalização Intercelular/biossíntese , Macrófagos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/análise , Fator de Crescimento Transformador beta1/biossíntese , Fator de Necrose Tumoral alfa/biossíntese
19.
J Urol ; 180(4 Suppl): 1757-60; discussion 1760, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18721951

RESUMO

PURPOSE: We report the long-term effectiveness of standard tap water for Malone antegrade continence enema irrigation as well as our algorithm for managing refractory constipation/fecal incontinence in a large single institution experience. MATERIALS AND METHODS: We retrospectively reviewed the charts of 256 Malone antegrade continence enema procedures performed for chronic constipation and/or incontinence due to neuropathic bowel. Continence, type of fluid used to irrigate the colon, volume of flushes and the need for additives were recorded and a database was created. All patients were initially treated with tap water irrigation. Those in whom tap water irrigation failed underwent complete bowel cleanout with enemas and GoLYTELY via the Malone antegrade continence enema, followed by a gradual increase in irrigation volume. If this was unsuccessful, additives of mineral oil, MiraLAX or glycerin were added to the irrigant daily. RESULTS: A total of 236 patients with at least 6 months of followup were included in this study. Mean age at surgery was 10.2 years (range 2 to 36) and mean followup in the entire cohort was 50 months (range 6 to 115). Mean volume of colonic flushes was 642 ml (range 100 to 1,000). Of the patients 196 (83.1%) achieved total fecal continence with tap water flushes alone. Using additives increased the overall continence rate to 93.6% (p <0.0001). CONCLUSIONS: The Malone antegrade continence enema procedure has proved invaluable for treating children with refractory constipation. When additives are used in conjunction with water flushes, they can significantly improve the overall fecal continence rate in partially continent children.


Assuntos
Constipação Intestinal/cirurgia , Enema/métodos , Incontinência Fecal/cirurgia , Disrafismo Espinal/cirurgia , Água , Adolescente , Adulto , Algoritmos , Criança , Pré-Escolar , Doença Crônica , Protocolos Clínicos , Constipação Intestinal/etiologia , Procedimentos Cirúrgicos do Sistema Digestório , Feminino , Humanos , Masculino , Estudos Retrospectivos
20.
J Urol ; 180(3): 1106-10, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18639902

RESUMO

PURPOSE: We report the long-term outcome of the Malone antegrade continence enema procedure in the treatment of chronic constipation and fecal incontinence in children with neuropathic bowel. MATERIALS AND METHODS: We performed a retrospective chart review of 256 Malone antegrade continence enema procedures. Patient age at surgery, bowel segment used, location of stoma, number and type of revisions required, and fecal continence were documented and a database was created. RESULTS: A total of 236 patients with at least 6 months of followup are included in this report. There were 172 in situ appendicocecostomies, 23 split appendix channels, 9 appendicocecostomies with cecal extension, 22 Yang-Monti ileocecostomies and 10 colon flap channels performed. A total of 112 males (47%) and 124 females (53%) were included in the study. Median patient age at surgery was 9 years (range 2 to 36) and median followup for the entire cohort was 50 months (6 to 115). A total of 56 surgical revisions were performed in 39 patients (17%). Median time to first revision was 9.5 months (range 1 to 105). Stomal stenosis occurred in 32 patients (14%). Overall, surgical revisions were required in 14% of in situ appendix channels (24 of 172), 22% of split appendix channels (5 of 23), 33% of appendix channels with cecal extension (3 of 9), 18% of Yang-Monti Malone antegrade continence enema channels (4 of 22) and 30% of colon flap channels (3 of 10). Independent of channel technique, surgical revisions were required in 15% of umbilical stomas and 18% of lower quadrant stomas (p = 0.516). Two patients had minimal stomal leakage, and 94% (221 of 236) achieved fecal continence with irrigations. CONCLUSIONS: The long-term results of the Malone antegrade continence enema channel in a large cohort of patients with neuropathic bowel and chronic constipation are encouraging. Of the patients 17% will require revision surgery, and patients/parents should be counseled accordingly. In our series in situ appendicocecostomy had the lowest revision rate on long-term followup, although the difference was not statistically significant (p = 0.226).


Assuntos
Constipação Intestinal/cirurgia , Enema/métodos , Incontinência Fecal/cirurgia , Adolescente , Adulto , Distribuição de Qui-Quadrado , Criança , Pré-Escolar , Procedimentos Cirúrgicos do Sistema Digestório , Feminino , Seguimentos , Humanos , Lactente , Masculino , Complicações Pós-Operatórias , Reoperação , Estudos Retrospectivos , Resultado do Tratamento
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