Novel echocardiographic pixel intensity quantification method for differentiating transthyretin cardiac amyloidosis from light chain cardiac amyloidosis and other phenocopies.

AIMS: Differentiating cardiac amyloidosis (CA) subtypes is important considering the significantly different therapies for transthyretin (ATTR)-CA and light chain (AL)-CA. Therefore, an echocardiographic method to distinguish ATTR-CA from AL-CA would provide significant value. We assessed a novel echocardiographic pixel intensity method to quantify myocardial calcification to differentiate ATTR-CA from phenocopies of CA and from AL-CA, specifically. METHODS AND RESULTS: 167 patients with ATTR-CA (n=53), AL-CA (n=32), hypertrophic cardiomyopathy (n=37), and advanced chronic kidney disease (n=45) were retrospectively evaluated. The septal reflectivity ratio (SRR) was measured as the average pixel intensity of the visible anterior septal wall divided by the average pixel intensity of the visible posterior lateral wall. SRR and other myocardial strain-based echocardiographic measures were evaluated with receiver operator characteristic analysis to evaluate accuracy in distinguishing ATTR-CA from AL-CA and other forms of left ventricular hypertrophy. Mean septal reflectivity ratio (SRR) was significantly higher in the ATTR-CA cohort compared to the other cohorts (p <0.001). SRR demonstrated the largest AUC (0.91, p<0.0001) for distinguishing ATTR from all other cohorts and specifically for distinguishing ATTR-CA from AL-CA (AUC=0.90, p<0.0001, specificity 96%, sensitivity 63%). There was excellent inter- and intra-operator reproducibility with an ICC of 0.91 (p <0.001) and 0.89 (p <0.001), respectively. CONCLUSION: The SRR is a reproducible and robust parameter for differentiating ATTR-CA from other phenocopies of CA and specifically ATTR-CA from AL-CA.

Radiographic and sonographic features, and histogram parameters of the liver and spleen in healthy Toco toucans (Ramphastos toco, Müller 1976).

This study aimed to evaluate radiographic and sonographic features, and histogram parameters based on grayscale ultrasound of the liver and spleen in healthy toco toucans. Fifteen adult toco toucans (Ramphastos toco), seven females and eight males, weighing approximately 650 g, were enrolled in the study. On the right lateral radiographic view, the liver was visualized in the midventral region of the coelomic cavity; ultrasonographically, the liver was located in the middle portion of the coelomic cavity in close relationship to the heart, and thoracic and abdominal air sacs. Two hepatic lobes were identified; the right lobe was larger than the left one. The spleen was visualized in 10 toco toucans on radiographs and only in eight toucans on ultrasound exams. The gallbladder was identified only on ultrasound. On the right lateral radiographic view, the spleen was visualized dorsal to the proventriculus and ventral to the lungs/air sacs as an oval shape. Ultrasonographically, the spleen was observed caudal to the liver, cranial to the proventriculus and craniodorsal to the ventriculus. There was no significant difference in spleen length for either radiographic or ultrasound measurements. The brightness intensity (BI) for mean gray level (G) and standard deviation of gray levels (SG ) in the liver were 101.315 (± 16.170) and 12.453 (± 2.616), respectively. Mean G and SG levels in the spleen were 63.940 (± 18.321) and 7.494 (± 3.595), respectively. In conclusion, the sonographic features and histogram parameters indicated that the liver is more echogenic and heterogeneous than the spleen, which must be considered for diagnosing alterations in these organs.

Ultrasonographic evaluation of the liver and gallbladder and hepatic histogram of non-venomous snakes.

This study aimed to describe sonographic features of the liver, gallbladder and hepatic histogram from grey-scale ultrasound in three species of healthy non-venomous snakes. Twenty-eight adult snakes were enrolled in the study, including 10 common boas (Boa constrictor), eight black-tailed pythons (Python molurus) and 10 rainbow boas (Epicrates crassus). The snakes fasted for 30 days and were manually restrained while conscious. For B. constrictor and P. molurus the liver and gallbladder were best visualized in ventral recumbency, and E. crassus in dorsal recumbency. A single elongated hepatic lobe was identified in all snakes. The gallbladder was positioned caudal and separated from the liver, with an oval shape and homogeneous anechoic content in the lumen, and thin and regular walls. A region of interest by pixel number was chosen for the liver, fat bodies, left kidney, and splenopancreas. The mean grey level (G) of the organs had significant differences within each species. Standard deviation of grey levels (SG ) had significant differences within B. constrictor and E. crassus. P. molurus had no significant difference among organs. The comparison among snakes showed that E. crassus had G of liver and splenopancreas lower than B. constrictor and P. molurus. The SG of the liver in E. crassus was lowest compared to B. constrictor and P. molurus. P. molurus showed the highest values in mean of G and SG . In conclusion, despite the liver and gallbladder having similar sonographic features, the grey-level histogram showed that liver echotexture and echogenicity differ among species.

Rules-based Volumetric Segmentation of Multiparametric MRI for Response Assessment in Recurrent High-Grade Glioma.

We report domain knowledge-based rules for assigning voxels in brain multiparametric MRI (mpMRI) to distinct tissuetypes based on their appearance on Apparent Diffusion Coefficient of water (ADC) maps, T1-weighted unenhanced and contrast-enhanced, T2-weighted, and Fluid-Attenuated Inversion Recovery images. The development dataset comprised mpMRI of 18 participants with preoperative high-grade glioma (HGG), recurrent HGG (rHGG), and brain metastases. External validation was performed on mpMRI of 235 HGG participants in the BraTS 2020 training dataset. The treatment dataset comprised serial mpMRI of 32 participants (total 231 scan dates) in a clinical trial of immunoradiotherapy in rHGG (NCT02313272). Pixel intensity-based rules for segmenting contrast-enhancing tumor (CE), hemorrhage, Fluid, non-enhancing tumor (Edema1), and leukoaraiosis (Edema2) were identified on calibrated, co-registered mpMRI images in the development dataset. On validation, rule-based CE and High FLAIR (Edema1 + Edema2) volumes were significantly correlated with ground truth volumes of enhancing tumor (R = 0.85;p < 0.001) and peritumoral edema (R = 0.87;p < 0.001), respectively. In the treatment dataset, a model combining time-on-treatment and rule-based volumes of CE and intratumoral Fluid was 82.5% accurate for predicting progression within 30 days of the scan date. An explainable decision tree applied to brain mpMRI yields validated, consistent, intratumoral tissuetype volumes suitable for quantitative response assessment in clinical trials of rHGG.

Inter-transducer variability of ultrasound image quality in obese adults: Qualitative and quantitative comparisons.

PURPOSE: Acquiring high-quality ultrasound images of deep abdominal organs and vasculatures in obese adults (BMI >30 kg/cm2) is considered challenging. The aim of the study was to assess the inter-transducer variability in B-mode and color Doppler image quality from four commercial ultrasound transducers through qualitative and quantitative analyses. METHODS: Four curvilinear transducers on three ultrasound scanners were used to acquire B-mode and color Doppler images of deep abdominal structures in 15 obesity ≥ class II (BMI >35 kg/cm2) adults. Using visual-qualitative assessment and an offline image processing software, visual-qualitative score and quantitative mean pixel values of B-mode images, and color area ratios of color Doppler images were calculated. Differences in these values among the transducers were analyzed using one-way ANOVA. The intra- and inter-observer reliability of visual-qualitative assessment and offline image processing was tested using the intraclass correlation coefficient (ICC). RESULTS: Differences in visual-qualitative score, mean pixel value of B-mode images, and color area ratio of color Doppler images among the four transducers were significant (p < 0.001). Transducer -4 produced the highest quality of B-mode (45-53% improvement) and color Doppler (22-73% improvement) images among the transducers. Intra-observer repeatability and inter-observer reproducibility were higher with performing offline image processing than visual-qualitative assessment (ICC: 0.97-0.99 versus ICC: 0.76-0.97). CONCLUSION: There was significant image quality variability between different transducers. Transducer -4, a transducer designed specifically for high BMI patients, had the highest quality B-mode and color Doppler images compared to the other transducers lending to improved ultrasonographic visualization in obese patients.

Collaborative multi-feature extraction and scale-aware semantic information mining for medical image segmentation.

Objective.In recent years, methods based on U-shaped structure and skip connection have achieved remarkable results in many medical semantic segmentation tasks. However, the information integration capability of this structure is still limited due to the incompatibility of feature maps of encoding and decoding stages at corresponding levels and lack of extraction of valid information in the final stage of encoding. This structural defect is particularly obvious in segmentation tasks with non-obvious, small and blurred-edge targets. Our objective is to design a novel segmentation network to solve the above problems.Approach.The segmentation network named Global Context-Aware Network is mainly designed by inserting a Multi-feature Collaboration Adaptation (MCA) module, a Scale-Aware Mining (SAM) module and an Edge-enhanced Pixel Intensity Mapping (Edge-PIM) into the U-shaped structure. Firstly, the MCA module can integrate information from all encoding stages and then effectively acts on the decoding stages, solving the problem of information loss during downsampling and pooling. Secondly, the SAM module can further mine information from the encoded high-level features to enrich the information passed to the decoding stage. Thirdly, Edge-PIM can further refine the segmentation results by edge enhancement.Main results.We newly collect Magnetic Resonance Imaging of Colorectal Cancer Liver Metastases (MRI-CRLM) dataset in different imaging sequences with non-obvious, small and blurred-edge liver metastases. Our method performs well on the MRI-CRLM dataset and the publicly available ISIC-2018 dataset, outperforming state-of-the-art methods such as CPFNet on multiple metrics after boxplot analysis, indicating that it can perform well on a wide range of medical image segmentation tasks.Significance.The proposed method solves the problem mentioned above and improved segmentation accuracy for non-obvious, small and blurred-edge targets. Meanwhile, the proposed visualization method Edge-PIM can make the edge more prominent, which can assist medical radiologists in their research work well.

Plasma-induced nanoparticle aggregation for stratifying COVID-19 patients according to disease severity.

Stratifying patients according to disease severity has been a major hurdle during the COVID-19 pandemic. This usually requires evaluating the levels of several biomarkers, which may be cumbersome when rapid decisions are required. In this manuscript we show that a single nanoparticle aggregation test can be used to distinguish patients that require intensive care from those that have already been discharged from the intensive care unit (ICU). It consists of diluting a platelet-free plasma sample and then adding gold nanoparticles. The nanoparticles aggregate to a larger extent when the samples are obtained from a patient in the ICU. This changes the color of the colloidal suspension, which can be evaluated by measuring the pixel intensity of a photograph. Although the exact factor or combination of factors behind the different aggregation behavior is unknown, control experiments demonstrate that the presence of proteins in the samples is crucial for the test to work. Principal component analysis demonstrates that the test result is highly correlated to biomarkers of prognosis and inflammation that are commonly used to evaluate the severity of COVID-19 patients. The results shown here pave the way to develop nanoparticle aggregation assays that classify COVID-19 patients according to disease severity, which could be useful to de-escalate care safely and make a better use of hospital resources.

A Comparison of Near-Infrared Imaging and Computerized Tomography Scan for Detecting Maxillary Sinusitis.

OBJECTIVE: To investigate the use of near-infrared (NIR) imaging as a tool for outpatient clinicians to quickly and accurately assess for maxillary sinusitis and to characterize its accuracy compared to computerized tomography (CT) scan. METHODS: In a prospective investigational study, NIR and CT images from 65 patients who presented to a tertiary care rhinology clinic were compared to determine the sensitivity and specificity of NIR as an imaging modality. RESULTS: The sensitivity and specificity of NIR imaging in distinguishing normal versus maxillary sinus disease was found to be 90% and 84%, normal versus mild maxillary sinus disease to be 76% and 91%, and mild versus severe maxillary sinus disease to be 96% and 81%, respectively. The average pixel intensity was also calculated and compared to the modified Lund-Mackay scores from CT scans to assess the ability of NIR imaging to stratify the severity of maxillary sinus disease. Average pixel intensity over a region of interest was significantly different (P < .001) between normal, mild, and severe disease, as well as when comparing normal versus mild (P < .001, 95% CI 42.22-105.39), normal versus severe (P < .001, 95% CI 119.43-174.14), and mild versus severe (P < .001, 95% CI 41.39-104.56) maxillary sinus disease. CONCLUSION: Based on this data, NIR shows promise as a tool for identifying patients with potential maxillary sinus disease as well as providing information on severity of disease that may guide administration of appropriate treatments.

Low-Cost Chlorophyll Fluorescence Imaging for Stress Detection.

Plants naturally contain high levels of the stress-responsive fluorophore chlorophyll. Chlorophyll fluorescence imaging (CFI) is a powerful tool to measure photosynthetic efficiency in plants and provides the ability to detect damage from a range of biotic and abiotic stresses before visible symptoms occur. However, most CFI systems are complex, expensive systems that use pulse amplitude modulation (PAM) fluorometry. Here, we test a simple CFI system, that does not require PAM fluorometry, but instead simply images fluorescence emitted by plants. We used this technique to visualize stress induced by the photosystem II-inhibitory herbicide atrazine. After applying atrazine as a soil drench, CFI and color images were taken at 15-minute intervals, alongside measurements from a PAM fluorometer and a leaf reflectometer. Pixel intensity of the CFI images was negatively correlated with the quantum yield of photosystem II (ΦPSII) (p < 0.0001) and positively correlated with the measured reflectance in the spectral region of chlorophyll fluorescence emissions (p < 0.0001). A fluorescence-based stress index was developed using the reflectometer measurements based on wavelengths with the highest (741.2 nm) and lowest variability (548.9 nm) in response to atrazine damage. This index was correlated with ΦPSII (p < 0.0001). Low-cost CFI imaging can detect herbicide-induced stress (and likely other stressors) before there is visual damage.

Outcome of degenerative nonprolapse mitral regurgitation using the average pixel intensity method.

BACKGROUND: Primary mitral valve regurgitation (MR) is a comprehensive term that mostly comprises mitral valve prolapse (MVP), while other causes of degenerative MR are often not considered. We describe the echocardiographic characteristics of degenerative nonprolapse mitral regurgitation (DMR) and assess the outcome at medium-term follow-up using the novel average pixel intensity (API) method. METHODS: Of 126 patients with any nonprolapse DMR were consecutively included. MR was graded according to all guideline-recommended parameters and with the API method. MR flow dynamics in DMR were compared to MVP-MR and functional MR (FMR). RESULTS: DMR is associated with moderate-to-severe calcifications of the mitral valve apparatus, and a low event rate was observed at a mean follow-up of 27 months. The API grading method had a higher feasibility (94%) compared to proximal isovelocity surface area (PISA) (60%) method and vena contracta width (VCW) (71%) for assessing MR. The API method was predictive for events. The API method also provides insights into DMR flow dynamics: A triphasic pattern was observed with a midsystolic nadir for both API and PISA-EROA, which is similar to the dynamic flow pattern described in FMR, but distinct from holosystolic MVP-MR. Compared to FMR and MVP-MR patients, DMR is less severe and patients with DMR are generally older than MVP-MR patients. CONCLUSIONS: DMR is a distinct MR pathology and conveys a relatively low event rate. MR grading was feasible with the API method, and flow dynamics demonstrated a similar triphasic pattern compared to FMR but distinct from holosystolic MVP-MR.

Sclerotic lesions of the femoral head-neck junction for diagnosis of femoroacetabular impingement.

The morphological characteristics associated with a diagnosis of femoroacetabular impingement (FAI) observed on plain radiographs can also be seen in subjects without hip joint symptoms. Therefore, the purpose of this study was to investigate whether sclerotic lesions on femoral head-neck junction (FHNJ) could be used as a supplemental diagnostic feature. A total of 128 hips from 119 patients (43 male and 76 female) diagnosed with FAI and 24 hips from 21 patients (2 male and 19 female) with other hip pathologies as control were compared in this study. Using standing frog-leg plain radiographs, the prevalence of sclerotic lesions on the FHNJ was established. Additionally, the pixel intensity (PI) of the sclerotic lesions between the FAI and the control groups were quantitatively compared. Sclerotic lesions were present in 96.1% of FAI hips (123 of 128) and only 37.5% of control hips (9 of 24) (p < 0.05). The ratio of PI in the FAI group was significantly higher (approximately 10%) than in the control group (p < 0.05). The evaluation of sclerotic lesions may be used as a supplement to aid in the diagnosis of FAI.

Light-cardiogram, a simple technique for heart rate determination in adult zebrafish, Danio rerio.

Current techniques for heart rate determination in adult zebrafish require specialist expertise and are often invasive, technically challenging and not readily transferable to other laboratories for routine assessment. Here, we present a simple, noninvasive and inexpensive light-cardiogram technique to assess heart rate and frequency in adult zebrafish. Brightfield microscope paired with a high-resolution camera and ImageJ (an open source software) were employed as core recording and processing platforms respectively. The heart was visualised ventrally and located by juxtaposing an isosceles triangle between the opercula as reference to analyse pixel intensity fluctuations generated by each cardiac cycle to derive heart rate and frequency. Compared to transparent embryos, the cardiograms generated reverse light signal oscillations, with contraction and relaxation of the heart (ventricle) corresponding to reduced and increased pixel intensities respectively. The heart rates (♂ 122.58 ± 2.15 and ♀ 121.37 ± 2.63 beat/min) and mean dominant frequency (♂ 2.04 ± 0.035 and ♀ 2.05 ± 0.048 Hz) between the sexes were not significantly (P > .05) different at 28 °C. However, the FD amplitudes between males (0.26 ± 0.03) and females (0.45 ± 0.05) were significantly different (P < .05) suggesting sex specific diastolic cardiac outputs. Collectively, the technique can be used to measure heartbeats as well as readily adaptable to record relative cardiac outputs and compare differences between physiological states (e.g. sexes). Moreover, the approach could be amenable to automation and applicable to other fish species, enabling researchers the flexibility to measure these and other critical heart health endpoint with relative ease.

The Average Pixel Intensity Method and Outcome of Mitral Regurgitation in Mitral Valve Prolapse.

BACKGROUND: Mitral regurgitation (MR) is a frequent consequence of mitral valve prolapse (MVP). However, the echocardiographic grading of MR is challenging, and the recommended grading parameters have several limitations. The authors developed a novel echocardiographic parameter to grade MR, the average pixel intensity (API) method, on the basis of pixel intensity analysis of the continuous-wave Doppler signal. METHODS: Transthoracic echocardiography was performed prospectively in consecutive patients with MVP (N = 149). MR was quantitatively assessed using the API method, vena contracta width, effective regurgitant orifice area, and regurgitant volume. The primary clinical events were cardiovascular mortality, mitral valve surgery, percutaneous mitral intervention, and heart failure hospitalization. RESULTS: The API method was feasible in 90% of all patients with MVP, which was significantly higher than vena contracta width, effective regurgitant orifice area, and regurgitant volume. During a median follow-up period of 17 months, 44 patients (32%) had major adverse cardiac events, and the majority of events occurred in the holosystolic MVP subgroup. The degree of MR severity by the API method was highly significant for the prediction of events. An API cutoff of 111 arbitrary units was defined as "severe" MR due to MVP, with overall superior sensitivity and specificity compared with cutoffs for established MR grading parameters. In patients who did not have major adverse cardiac events during the follow-up period (n = 92), no significant changes in measures of MR severity were found on follow-up echocardiography. CONCLUSIONS: The API method is predictive of clinical events and outcomes in MR due to MVP. Therefore, the API method may be considered for grading the severity of MR due to MVP in clinical practice.

Insights into functional mitral regurgitation using the average pixel intensity method.

Previously we introduced and validated the average pixel intensity (API) method for grading mitral regurgitation (MR) in a heterogeneous MR population. We now investigated the feasibility and added value of the API method more specifically in patients with functional MR (FMR). We consecutively enrolled 283 patients with pure FMR. Transthoracic echocardiography was performed and MR was assessed using the API method and guideline-recommended parameters, including color Doppler, vena contracta width (VCW) and proximal isovelocity surface area (PISA)-based methods. The API method had an applicability of 98% in this FMR cohort, which was significantly higher than VCW (84%) and PISA-based methods (75%). Overall, the API method had significant correlations with direct parameters of FMR severity, ejection fraction, atrial and ventricular dimensions, pulmonary pressures and New York Heart Association class. Analysis of the API dynamics during MR revealed a typical pattern with early and late systolic peaks in API and a midsystolic nadir, which matched the temporal changes of the effective regurgitant orifice (ERO) during FMR. Based on ROC curves of established FMR severity cut-offs, an API value of 125 au was considered the optimal cut-off to determine severe MR. Interestingly, this API severity cut-off is similar to the API severity cut-off for MR in degenerative MR (DMR), despite different EROA/RV cut-offs in current ESC guidelines for FMR and DMR. The API method is an easy, fast and feasible parameter for grading FMR and may complement the multiparametric assessment of FMR in daily clinical practice.

A simple quality control tool for assessing integrity of lead equivalent aprons.

BACKGROUND: Protective lead or lead-equivalent (Pbeq) aprons play a key role in providing necessary shielding from secondary radiation to occupational workers. Knowledge on the integrity of these shielding apparels during purchase is necessary to maintain adequate radiation safety. AIM: The aim of the study was to evaluate the lead equivalence in aprons based on simple quality assessment tool. MATERIALS AND METHODS: 0.25 mm and 0.5 mm lead and lead-free aprons from 6 manufacturers were assessed using a calibrated digital X-ray unit. The percentage attenuation values of the aprons were determined at 100 kVp using an ionization chamber and the pixel intensities were analyzed using digital radiographic images of lead apron, copper step wedge tool, and 2 mm thick lead. RESULTS: Mean radiation attenuation of 90% and 97% was achieved in 0.25 mm and 0.5 mm lead or lead-free aprons respectively. The pixel intensities from 0.25 mm Pbeq apron correspond to 0.8-1.2 mm thickness of Cu while 0.5 mm Pbeq aprons correspond to 2.0-2.8 mm of Cu. CONCLUSION: Pixel intensity increased with increase in the thickness of copper step wedge indicating a corresponding increase in lead equivalence in aprons. It is suggestive that aprons should be screened for its integrity from the time of purchase using computed tomography (CT), fluoroscopy, or radiography. It is recommended that this simple test tool could be used for checking lead equivalence if any variation in contrast is seen in the image during screening.

Objective quantification of corneal haziness using anterior segment optical coherence tomography.

PURPOSE: To quantify normal corneal transparency by anterior segment optical coherence tomography (AS-OCT) by measuring the average pixel intensity. To analyze the variation in the average pixel intensity in mild and severe grades of corneal opacities. METHODS: This is an observational, cross-sectional study of 38 eyes from 19 patients with mild or severe grades of corneal opacities greater than 3 mm and a normal contralateral cornea. AS-OCT was performed centered on the opacity with a 3 mm cruciate protocol. A similar image is taken of the contralateral clear cornea in the same quadrant. The average pixel intensity was calculated in a standardized manner using MATLAB software. RESULT: The average pixel intensity of the normal cornea was 99.6 ± 10.9 [standard deviation (SD)]. The average pixel intensity of the mild and severe corneal opacities was 115.5 ± 9.1 and 141.1 ± 10.3, respectively. The differences were statistically significant. CONCLUSIONS: AS-OCT images can be used to quantify corneal transparency. Average pixel intensity is a measure that varies significantly with varying corneal opacification.

Quantification of Bacterial Chemotaxis Responses at the Mouths of Hydrogel Capillaries.

Many chemotaxis assays allow for the assessment of bacterial chemotaxis by determining the number of cells migrating toward a chemoattractant or away from a chemorepellent. Some of these assays use a capillary filled with a chemoeffector/agarose mixture to allow cells to accumulate at the mouth of the capillary. Subsequently, assumptions about the relative strengths of chemotaxis strength are based on visual comparisons. Here, we describe a modification of this assay that uses a hydrogel matrix to enable quantitative time-course measurements by analyzing image pixel intensities. This approach allows a high-throughput method when coupled with the aid of a motorized microscope stage.

The value of trans-scrotal ultrasonography at bull breeding soundness evaluation (BBSE): The relationship between testicular parenchymal pixel intensity and semen quality.

Bull breeding soundness evaluation (BBSE) is commonly undertaken to identify bulls that are potentially unfit for use as breeding sires. Various studies worldwide have found that approximately 20% of the bulls fail their routine prebreeding BBSE and are therefore considered subfertile. Multiple articles describe the use of testicular ultrasound as a noninvasive aid in the identification of specific testicular and epididymal lesions. Two previous studies have hypothesized a correlation between ultrasonographic testicular parenchymal pixel intensity (PI) and semen quality; however to date, no published studies have specifically examined this link. The aim of this study, therefore, was to assess the relationship between testicular parenchymal PI (measured using trans-scrotal ultrasonography) and semen quality (measured at BBSE), and the usefulness of testicular ultrasonography as an aid in predicting future fertility in bulls, in particular those that are deemed subfertile at the first examination. A total of 162 bulls from 35 farms in the South East of Scotland were submitted to routine BBSE and testicular ultrasonography between March and May 2014, and March and May 2015. Thirty-three animals failed their initial examination (BBSE1) due to poor semen quality, and were re-examined (BBSE2) 6 to 8 weeks later. Computer-aided image analysis and gross visual lesion scoring were performed on all ultrasonograms, and results were compared to semen quality at BBSE1 and BBSE2. The PI measurements were practical and repeatable in a field setting, and although the results of this study did not highlight any biological correlation between semen quality at BBSE1 or BBSE2 and testicular PI, it did identify that gross visual lesion scoring of testicular images is comparable to computer analysis of PI (P < 0.001) in identifying animals suffering from gross testicular fibrosis.

Seminal plasma protein concentrations vary with feed efficiency and fertility-related measures in young beef bulls.

Fertility-associated proteins (FAP) found in seminal plasma indicate sexual maturity, which appears to be influenced by feed efficiency in cattle. This study characterized FAP via proteomics and verified associations of these proteins with feed efficiency, body composition and fertility-related measures in yearling beef bulls. Assessments including testicular ultrasonography, infrared thermography, seminal quality, seminal plasma proteomics, carcass composition, and reproductive organ biometry were obtained. From a population of 31 bulls, the seven most and least feed efficient (efficient, inefficient) bulls were used for categorical comparisons. Correlations between FAP, productive performance and fertility-related measures were determined. These traits were also correlated with orthogonal factors summarized from the FAP. Efficient bulls had increased epididymal sperm-binding protein-1 and decreased concentration of protein-C inhibitor compared to inefficient bulls. Correlations between FAP with age, body size, body composition, reproductive organ biometry, scrotal temperature, and seminiferous tubule maturity are reported. Acrosin and cathepsin D increased with development of the testes and osteopontin increased with greater numbers of mature seminiferous tubules. Phosphoglycerate kinase-2 was higher in animals with a higher scrotum temperature and a higher prevalence of sperm morphology defects. The principal factor indicated that FAP variability concentrations were positively correlated with age, reproductive organ biometry, body size and composition. Our results indicate that FAP changes with body size and sexual development, and demonstrates differences in the proteomics of bulls with diverging feed efficiency. This is related to the delay in the sexual maturity of efficient young bulls.

Impact of pixel intensity correlations on statistical inferences of expression levels in cDNA microarray experiments.

In a cDNA microarray experiment, the final measurement is intensity ratio at a spot in the microarray chip. The objective of the present study is to estimate the uncertainty associated with the final intensity ratio at each spot in cDNA microarray chips and also to explore the role of pixel intensity correlations in statistical inferences of gene expression levels. We estimate uncertainty at each spot using the theory of error propagation under two different situations: (1) when there is no correlation between pixel intensities and (2) when the pixel intensities are positively correlated. The inverses of these estimated uncertainties are used as weights in downstream analysis to test the significance of each gene. The analysis was verified on a data downloaded from the GEO database. Our study shows that the uncertainty and statistical inference of gene expression levels depend on correlation between pixel intensities within a spot.