Quantificação computadorizada dos índices de placa e cálculo dentais da imagem digital da superfície vestibular dos dentes de cães

A doença periodontal é causada pelo acúmulo de placa bacteriana sobre os dentes e estruturas adjacentes. Para sua mensuração têm sido formulados índices que consideram a quantidade e intensidade de placa bacteriana (PB) e de cálculo dental (CD) existentes na superfície dentária por meio de avaliação visual subjetiva. O presente estudo tem como objetivo avaliar o método de análise computadorizada para medição de área de PB e CD nos dentes de cães através da comparação com a avaliação visual. Foram utilizados 10 cães Beagles, três machos e sete fêmeas, com similares características e mantidos sob o mesmo manejo e dieta alimentar. As avaliações das superfícies vestibulares dos dentes ocorreram antes da profilaxia dentária, que foi realizada sob anestesia geral inalatória, e após sete dias para PB e após 28 dias para CD. A avaliação computadorizada da área de CD demonstrou ser estatisticamente melhor em relação à avaliação visual antes e após a profilaxia; entretanto, não demonstrou diferença significante na avaliação da PB. Concluiu-se que a avaliação computadorizada é vantajosa em relação à visual por conferir maior precisão na obtenção da proporção entre área total do dente e área acometida, mostrando-se estatistticamente superior na quantificação do CD após 28 dias.

Digital dermatitis of the accessory digits of dairy cows

This report characterizes the digital dermatitis (DD) lesions in the accessory digits of dairy cows and presents data on the applied therapy. Fifteen Holstein cattle with DD affecting the accessory digits of the hindlimbs from four dairy farms with previous history of DD were evaluated. Lesions were excised, the wounds were sutured, and a topical application of oxytetracycline powder covered by bandaging was associated with a single parenteral administration of long acting oxytetracycline IM (20mg/kg). Tissue samples were obtained for histopathology and transmission electronic microscopy (TEM). Lesions from all the animals were recuperated 15 days after surgical procedure. Overal, most DD lesions were papillomatous epidermal projections or wartlike verrucous lesions. Histopathologically, samples revealed hyperplasia of epidermis with hyperkeratosis, several mitoses in the stratum basale and elongated rete ridges in the superficial and middle dermis. TEM revealed long, thin spirochete-like bacteria. Morphologic features of lesions and its response to therapy were comparable to those described for DD.

Evaluation of follicular lymphoid depletion in the Bursa of Fabricius: an alternative methodology using digital image analysis and artificial neural networks

Fifty Bursa of Fabricius (BF) were examined by conventional optical microscopy and digital images were acquired and processed using Matlab® 6.5 software. The Artificial Neuronal Network (ANN) was generated using Neuroshell® Classifier software and the optical and digital data were compared. The ANN was able to make a comparable classification of digital and optical scores. The use of ANN was able to classify correctly the majority of the follicles, reaching sensibility and specificity of 89% and 96%, respectively. When the follicles were scored and grouped in a binary fashion the sensibility increased to 90% and obtained the maximum value for the specificity of 92%. These results demonstrate that the use of digital image analysis and ANN is a useful tool for the pathological classification of the BF lymphoid depletion. In addition it provides objective results that allow measuring the dimension of the error in the diagnosis and classification therefore making comparison between databases feasible.

Serial superficial digital flexor tendon biopsies for diagnosing and monitoring collagenase-induced tendonitis in horses

The purpose of this investigation was to demonstrate the feasibility of a biopsy technique by performing serial evaluations of tissue samples of the forelimb superficial digital flexor tendon (SDFT) in healthy horses and in horses subjected to superficial digital flexor tendonitis induction. Eight adult horses were evaluated in two different phases (P), control (P1) and tendonitis-induced (P2). At P1, the horses were subjected to five SDFT biopsies of the left forelimb, with 24 hours (h) of interval. Clinical and ultrasonographic (US) examinations were performed immediately before the tendonitis induction, 24 and 48 h after the procedure. The biopsied tendon tissues were analyzed through histology. P2 evaluations were carried out three months later, when the same horses were subjected to tendonitis induction by injection of bacterial collagenase into the right forelimb SDFT. P2 clinical and US evaluations, and SDFT biopsies were performed before, and after injury induction at the following time intervals: after 24, 48, 72 and 96 h, and after 15, 30, 60, 90, 120 and 150 days. The biopsy technique has proven to be easy and quick to perform and yielded good tendon samples for histological evaluation. At P1 the horses did not show signs of localised inflammation, pain or lameness, neither SDFT US alterations after biopsies, showing that the biopsy procedure per se did not risk tendon integrity. Therefore, this procedure is feasible for routine tendon histological evaluations. The P2 findings demonstrate a relation between the US and histology evaluations concerning induced tendonitis evolution. However, the clinical signs of tendonitis poorly reflected the microscopic tissue condition, indicating that clinical presentation is not a reliable parameter for monitoring injury development. The presented method of biopsying SDFT tissue in horses enables the serial collection of material for histological analysis causing no clinical signs and tendon damage seen by US images. Therefore, this technique allows tendonitis to be monitored and can be considered an excellent tool in protocols for evaluating SDFT injury.

Evaluation of bursal lymphoid depletion: comparison between the conventional histology method and digital lymphocyte depletion evaluation system

Abstract: Fifty-five bursa of Fabricius (BF) were evaluated by optical microscopy for three different avian histopathologists (H1, H3 and H4) to determine the degree of lymphoid depletion. One histologist evaluated the same slides at two different times (H1 and H2) with four-months interval between the observations. The same BFs were evaluated using the system of Digital Lymphocyte Depletion Evaluation (ADDL), being performed by three differents operators of the system, not histopathologists. The results showed was a significant difference between the histopathologists and between the scores established by the same expert (H1 and H2). However, there were not significant differences between the scores with the ADDL system, obtained using ADDL. The results make clear the fragility of the subjective lymphocyte depletion score classification by the traditional histologic method, while the ADDL system proves to be more appropriated for the assessment of the lymphoid loss in the BF.

Morphoquantitative description of bovine digital cushion

Abstract The digital cushion is characterized as a modified subcutaneous tissue that absorbs the shock during gait, assists venous return of the hoof and supports a considerable part of body weight. Digital cushions have particular importance in the pathogenesis of the hoof, since they need to properly work in order to prevent compression and traumas in soft tissues. This study aimed to measure and determine how is the arrangement of these structures, and for this it was established the proportions of connective, adipose, vascular tissues and collagen fibers and collagen types found in palmar and plantar digital cushion of bovine using fore and hindlimbs of twelve adult zebu cattle of both sexes, 11 male and one female, with 269kg average carcass weight and without limb disorders. Fragments of cushions were subjected to conventional histology, cut to a thickness of 4µm and stained with Red Picrosirius. With digital optical microscope, the quantification of the connective tissue and differentiation of types of collagen used the Image Pro Plus® software, and of adipose and vascular tissue, the test point system. The mean and standard error were estimated with the GraphPad Prism 5.0 software, and then data were subjected to Kolmogorov-Smirnov normality test and Student's t-test with significance level set at 5% for determining the amount of different tissues between fore and hindlimbs of studied animals. In forelimbs the mean and standard error of the connective tissue proportion was 50.10%+1.54, of the adipose tissue was 21.34%+1.44, and of vascular tissue was 3.43%+0.28. Hindlimbs presented a proportion of connective tissue of 61.61%+1.47, 20.66%+1.53 of adipose tissue, and 3.06%+0.20 of vascular tissue. A significant difference (p<0.001) was detected in the connective tissue proportion between fore and hindlimbs. Types I and II collagen fibers have presented, respectively, a proportion of 31.89% and 3.9% in forelimbs and 34.05% and 1.78% in hindlimbs. According to the used methodology, digital cushions had a clear differentiation relative to adipose tissue between fore and hindlimbs.

Modeling and control of multibody system with flexible appendages

The objective of this work is to describe the design and the implementation of an experiment to study the dynamics and the active control of a slewing multi-link flexible structure. The experimental apparatus was designed to be representative of a flexible space structure such as a satellite with multiple flexible appendages. In this study we describe the design procedures, the analog and digital instrumentation, the analytical modeling together with model validation studies carried out through experimental modal testing and parametric system identification studies in the frequency domain. Preliminary results of a simple positional control where the sensor and the actuator are positioned physically at the same point is also described.

The Shadow Moiré method using the phase shifting technique and digital image processing: computational implementation and application to the 3D-reconstruction of a buckled plate

The Shadow Moiré fringe patterns are level lines of equal depth generated by interference between a master grid and its shadow projected on the surface. In simplistic approach, the minimum error is about the order of the master grid pitch, that is, always larger than 0,1 mm, resulting in an experimental technique of low precision. The use of a phase shift increases the accuracy of the Shadow Moiré technique. The current work uses the phase shifting method to determine the surfaces three-dimensional shape using isothamic fringe patterns and digital image processing. The current study presents the method and applies it to images obtained by simulation for error evaluation, as well as to a buckled plate, obtaining excellent results. The method hands itself particularly useful to decrease the errors in the interpretation of the Moiré fringes that can adversely affect the calculations of displacements in pieces containing many concave and convex regions in relatively small areas.

Heart rate variability under resting conditions in postmenopausal and young women

The aim of the present study was to compare the modulation of heart rate in a group of postmenopausal women to that of a group of young women under resting conditions on the basis of R-R interval variability. Ten healthy postmenopausal women (mean ± SD, 58.3 ± 6.8 years) and 10 healthy young women (mean ± SD, 21.6 ± 0.82 years) were submitted to a control resting electrocardiogram (ECG) in the supine and sitting positions over a period of 6 min. The ECG was obtained from a one-channel heart monitor at the CM5 lead and processed and stored using an analog to digital converter connected to a microcomputer. R-R intervals were calculated on a beat-to-beat basis from the ECG recording in real time using a signal-processing software. Heart rate variability (HRV) was expressed as standard deviation (RMSM) and mean square root (RMSSD). In the supine position, the postmenopausal group showed significantly lower (P<0.05) median values of RMSM (34.9) and RMSSD (22.32) than the young group (RMSM: 62.11 and RMSSD: 49.1). The same occurred in the sitting position (RMSM: 33.0 and RMSSD: 18.9 compared to RMSM: 57.6 and RMSSD: 42.8 for the young group). These results indicate a decrease in parasympathetic modulation in postmenopausal women compared to young women which was possibly due both to the influence of age and hormonal factors. Thus, time domain HRV proved to be a noninvasive and sensitive method for the identification of changes in autonomic modulation of the sinus node in postmenopausal women.

Clinical assessment of the effect of digital filtering on the detection of ventricular late potentials

Ventricular late potentials are low-amplitude signals originating from damaged myocardium and detected on the body surface by ECG filtering and averaging. Digital filters present in commercial equipment may interfere with the ability of arrhythmia stratification. We compared 40-Hz BiSpec (BI) and classical 40- to 250-Hz band-pass Butterworth bidirectional (BD) filters in terms of impact on time domain variables and diagnostic properties. In a transverse retrospective age-adjusted case-control study, 221 subjects with sinus rhythm without bundle branch block were divided into three groups after signal-averaged ECG acquisition: GI (N = 40), clinically normal controls, GII (N = 158), subjects with coronary heart disease without sustained monomorphic ventricular tachycardia (SMVT), and GIII (N = 23), subjects with heart disease and documented SMVT. Conventional variables analyzed from vector magnitude data after averaging to 0.3 µV final noise were obtained by application of each filter to the averaged signal, and evaluated in pairs by numerical comparison and by diagnostic agreement assessment, using conventional and optimized thresholds of normality. Significant differences were found between BI and BD variables in all groups, with diagnostic results showing significant disagreement between both filters [kappa value of 0.61 (P<0.05) for GII and 0.31 for GIII (P = NS)]. Sensitivity for SMVT was lower with BI than with BD (65.2 vs 91.3%, respectively, P<0.05). Filters provided significantly different numerical and diagnostic results and the BI filter showed only limited clinical application to risk stratification of ventricular arrhythmia.

What can digital transcript profiling reveal about human cancers?

Important biological and clinical features of malignancy are reflected in its transcript pattern. Recent advances in gene expression technology and informatics have provided a powerful new means to obtain and interpret these expression patterns. A comprehensive approach to expression profiling is serial analysis of gene expression (SAGE), which provides digital information on transcript levels. SAGE works by counting transcripts and storing these digital values electronically, providing absolute gene expression levels that make historical comparisons possible. SAGE produces a comprehensive profile of gene expression and can be used to search for candidate tumor markers or antigens in a limited number of samples. The Cancer Genome Anatomy Project has created a SAGE database of human gene expression levels for many different tumors and normal reference tissues and provides online tools for viewing, comparing, and downloading expression profiles. Digital expression profiling using SAGE and informatics have been useful for identifying genes that have a role in tumor invasion and other aspects of tumor progression.

Computerized invasive measurement of time-dependent intraocular pressure

Several methods have been described to measure intraocular pressure (IOP) in clinical and research situations. However, the measurement of time varying IOP with high accuracy, mainly in situations that alter corneal properties, has not been reported until now. The present report describes a computerized system capable of recording the transitory variability of IOP, which is sufficiently sensitive to reliably measure ocular pulse peak-to-peak values. We also describe its characteristics and discuss its applicability to research and clinical studies. The device consists of a pressure transducer, a signal conditioning unit and an analog-to-digital converter coupled to a video acquisition board. A modified Cairns trabeculectomy was performed in 9 Oryctolagus cuniculus rabbits to obtain changes in IOP decay parameters and to evaluate the utility and sensitivity of the recording system. The device was effective for the study of kinetic parameters of IOP, such as decay pattern and ocular pulse waves due to cardiac and respiratory cycle rhythm. In addition, there was a significant increase of IOP versus time curve derivative when pre- and post-trabeculectomy recordings were compared. The present procedure excludes corneal thickness and error related to individual operator ability. Clinical complications due to saline infusion and pressure overload were not observed during biomicroscopic evaluation. Among the disadvantages of the procedure are the requirement of anesthesia and the use in acute recordings rather than chronic protocols. Finally, the method described may provide a reliable alternative for the study of ocular pressure dynamic alterations in man and may facilitate the investigation of the pathogenesis of glaucoma.

Similaridade entre os valores da pressão arterial aferida pelo método auscultatório com aparelho de coluna de mercúrio e o método oscilométrico automático com aparelho digital

INTRODUÇÃO: Um dos maiores desafios no manejo da hipertensão arterial é o adequado controle pressórico. Para se alcançar esse objetivo tem se difundido a medida residencial da pressão arterial (MRPA) com aparelhos automáticos. Entretanto, parte da comunidade médico-científica ainda discute sua validade, acreditando que as medidas pressóricas domiciliares podem ser incorretas. OBJETIVO: Avaliar a correspondência entre as medidas simultâneas da pressão arterial (PA) pelo método auscultatório convencional e método digital automático, habitualmente utilizado na MRPA. MÉTODOS: Através de uma conexão em "Y" acoplamos um manguito a um aparelho digital automático validado (ONROM 705IT) e a um esfigmomanômetro de coluna de mercúrio, permitindo aferir simultaneamente a PA pelos dois métodos. Determinamos a PA em 423 indivíduos (normotensos e hipertensos), adequando o tamanho do manguito à circunferência braquial. RESULTADOS: Os valores representam média ± desvio padrão (DP) (valores mínimo-máximo): Idade 40,8 ± 16,3 anos (18-92), circunferência braquial 28,2 ± 3,7 cm (19-42), PA sistólica (PAS) auscultatório 127,6 ± 22,8 mmHg (69-223), PAS automático 129,5 ± 23,0 mmHg (56-226), PA diastólica (PAD) auscultatório 79,5 ± 12,6 mmHg (49-135), PAD automático 79,0 ± 12,6 mmHg (48-123). A diferença média da PAS entre os dois métodos foi de 1,9 mmHg (-15 a +19) e a diferença da PAD de 0,5 mmHg (-19 a +13). Os índices de correlação de Pearson entre os métodos são para a PAS (r = 0,97), e PAD (r = 0,91). A análise de Bland-Altman mostrou concordância clinicamente aceitável entre os métodos. CONCLUSÃO: A PA aferida pelo método digital automático apresenta boa concordância com o método auscultatório convencional, devendo ser usada no auxílio do diagnóstico e controle da hipertensão arterial (HA).