e-CoVig: A Novel mHealth System for Remote Monitoring of Symptoms in COVID-19.

In 2019, a new virus, SARS-CoV-2, responsible for the COVID-19 disease, was discovered. Asymptomatic and mildly symptomatic patients were forced to quarantine and closely monitor their symptoms and vital signs, most of the time at home. This paper describes e-CoVig, a novel mHealth application, developed as an alternative to the current monitoring paradigm, where the patients are followed up by direct phone contact. The e-CoVig provides a set of functionalities for remote reporting of symptoms, vital signs, and other clinical information to the health services taking care of these patients. The application is designed to register and transmit the heart rate, blood oxygen saturation (SpO2), body temperature, respiration, and cough. The system features a mobile application, a web/cloud platform, and a low-cost specific device to acquire the temperature and SpO2. The architecture of the system is flexible and can be configured for different operation conditions. Current commercial devices, such as oximeters and thermometers, can also be used and read using the optical character recognition (OCR) functionality of the system. The data acquired at the mobile application are sent automatically to the web/cloud application and made available in real-time to the medical staff, enabling the follow-up of several users simultaneously without the need for time consuming phone call interactions. The system was already tested for its feasibility and a preliminary deployment was performed on a nursing home showing promising results.

E-cadherin signal sequence disruption: a novel mechanism underlying hereditary cancer.

The aim of this study was to uncover the pathogenic relevance and the underlying molecular mechanism of a novel CDH1 variant found in a Hereditary Diffuse Gastric Cancer family (p.L13_L15del), which affects the signal peptide of E-cadherin without changing the remaining predicted sequence. We verified that p.L13_L15del cells yield low levels of E-cadherin, decreased cell adhesion and enhanced cell invasion. Further, we demonstrated that the disruption of the highly conserved hydrophobic core of the signal peptide hampers the binding of cellular components crucial for E-cadherin translation and translocation into the endoplasmic reticulum, constituting a new molecular basis for the loss of a tumour suppressor gene causative of hereditary cancer.

SRC inhibition prevents P-cadherin mediated signaling and function in basal-like breast cancer cells.

BACKGROUND: Basal-like breast cancer (BLBC) is a poor prognosis subgroup of triple-negative carcinomas that still lack specific target therapies and accurate biomarkers for treatment selection. P-cadherin is frequently overexpressed in these tumors, promoting cell invasion, stem cell activity and tumorigenesis by the activation of Src-Family kinase (SRC) signaling. Therefore, our aim was to evaluate if the treatment of BLBC cells with dasatinib, the FDA approved SRC inhibitor, would impact on P-cadherin induced tumor aggressive behavior. METHODS: P-cadherin and SRC expression was evaluated in a series of invasive Breast Cancer and contingency tables and chi-square tests were performed. Cell-cell adhesion measurements were performed by Atomic Force Microscopy, where frequency histograms and Gaussian curves were applied. 2D and 3D cell migration and invasion, proteases secretion and self-renew potential were evaluated in vitro. Student's t-tests were used to determine statistically significant differences. The cadherin/catenin complex interactions were evaluated by in situ proximity-ligation assay, and statistically significant results were determined by using Mann-Whitney test with a Bonferroni correction. In vivo xenograft mouse models were used to evaluate the impact of dasatinib on tumor growth and survival. ANOVA test was used to evaluate the differences in tumor size, considering a confidence interval of 95%. Survival curves were estimated by the Kaplan-Meier's method, using the log-rank test to assess significant differences for mice overall survival. RESULTS: Our data demonstrated that P-cadherin overexpression is significantly associated with SRC activation in breast cancer cells, which was also validated in a large series of primary tumor samples. SRC activity suppression with dasatinib significantly prevented the in vitro functional effects of P-cadherin overexpressing cells, as well as their in vivo tumorigenic and metastatic ability, by increasing mice overall survival. Mechanistically, SRC inhibition affects P-cadherin downstream signaling, rescues the E-cadherin/p120-catenin complex to the cell membrane, recovering cell-cell adhesion function. CONCLUSIONS: In conclusion our findings show that targeting P-cadherin/SRC signaling and functional activity may open novel therapeutic opportunities for highly aggressive and poor prognostic basal-like breast cancer.

Targeting the PI3K Signalling as a Therapeutic Strategy in Colorectal Cancer.

Colorectal cancer (CRC) remains one of the leading causes of cancer mortality worldwide. Regarded as a heterogeneous disease, a number of biomarkers have been proposed to help in the stratification of CRC patients and to enable the selection of the best therapy for each patient towards personalized therapy. However, although the molecular mechanisms underlying the development of CRC have been elucidated, the therapeutic strategies available for these patients are still quite limited. Thus, over the last few years, a multitude of novel targets and therapeutic strategies have emerged focusing on deregulated molecules and pathways that are implicated in cell growth and survival. Particularly relevant in CRC are the activating mutations in the oncogene PIK3CA that frequently occur in concomitancy with KRAS and BRAF mutations and that lead to deregulation of the major signalling pathways PI3K and MAPK, downstream of EGFR. This review focus on the importance of the PI3K signalling in CRC development, on the current knowledge of PI3K inhibition as a therapeutic approach in CRC and on the implications PI3K signalling molecules may have as potential biomarkers and as new targets for directed therapies in CRC patients.

Blue intensity matters for cell cycle profiling in fluorescence DAPI-stained images.

In the past decades, there has been an amazing progress in the understanding of the molecular mechanisms of the cell cycle. This has been possible largely due to a better conceptualization of the cycle itself, but also as a consequence of technological advances. Herein, we propose a new fluorescence image-based framework targeted at the identification and segmentation of stained nuclei with the purpose to determine DNA content in distinct cell cycle stages. The method is based on discriminative features, such as total intensity and area, retrieved from in situ stained nuclei by fluorescence microscopy, allowing the determination of the cell cycle phase of both single and sub-population of cells. The analysis framework was built on a modified k-means clustering strategy and refined with a Gaussian mixture model classifier, which enabled the definition of highly accurate classification clusters corresponding to G1, S and G2 phases. Using the information retrieved from area and fluorescence total intensity, the modified k-means (k=3) cluster imaging framework classified 64.7% of the imaged nuclei, as being at G1 phase, 12.0% at G2 phase and 23.2% at S phase. Performance of the imaging framework was ascertained with normal murine mammary gland cells constitutively expressing the Fucci2 technology, exhibiting an overall sensitivity of 94.0%. Further, the results indicate that the imaging framework has a robust capacity to both identify a given DAPI-stained nucleus to its correct cell cycle phase, as well as to determine, with very high probability, true negatives. Importantly, this novel imaging approach is a non-disruptive method that allows an integrative and simultaneous quantitative analysis of molecular and morphological parameters, thus awarding the possibility of cell cycle profiling in cytological and histological samples.

Predicting the Functional Impact of CDH1 Missense Mutations in Hereditary Diffuse Gastric Cancer.

The role of E-cadherin in Hereditary Diffuse Gastric Cancer (HDGC) is unequivocal. Germline alterations in its encoding gene (CDH1) are causative of HDGC and occur in about 40% of patients. Importantly, while in most cases CDH1 alterations result in the complete loss of E-cadherin associated with a well-established clinical impact, in about 20% of cases the mutations are of the missense type. The latter are of particular concern in terms of genetic counselling and clinical management, as the effect of the sequence variants in E-cadherin function is not predictable. If a deleterious variant is identified, prophylactic surgery could be recommended. Therefore, over the last few years, intensive research has focused on evaluating the functional consequences of CDH1 missense variants and in assessing E-cadherin pathogenicity. In that context, our group has contributed to better characterize CDH1 germline missense variants and is now considered a worldwide reference centre. In this review, we highlight the state of the art methodologies to categorize CDH1 variants, as neutral or deleterious. This information is subsequently integrated with clinical data for genetic counseling and management of CDH1 variant carriers.

Comparing open and closed cell stents in idiopathic intracranial hypertension: A comprehensive meta-analysis of clinical outcomes.

Background: Open cell stents (OC) and closed cell stents (CC) each offer unique advantages and potential drawbacks in the context of idiopathic intracranial hypertension (IIH) treatment. We aim to investigate the safety and efficacy of using OC and CC for IIH.Methods: We conducted a systematic review in PubMed, Embase, and Cochrane Library databases following the PRISMA guidelines. Eligible studies included ≥4 patients with IIH treated by OC or CC. Primary outcomes were headache, visual acuity, and papilledema status before and after the procedure. Additionally, failure rate, minor complications, major complications, and total complications were assessed. Pooled analysis of the OC group and CC group were done separately and then compared.Results: Twenty-four studies were included. Of these, 20 reported on OC and 6 reported on CC. Pooled analysis of failure rate was 8% (4%-12%) in OC and 5% (0%-11%) in CC. For headache improvement rate: 78% (70%-86%) in OC and 81% (66%-69%) in CC. For visual acuity improvement: 78% (65%-92%) in OC and 76% (29%-100%) in CC. For papilledema improvement: 88% (77%-98%) in OC and 82% (67%-98%) in CC. For minor complications: 0% (0%-1%) in OC and 0% (0%-2%) in CC. For major complications: 0% (0%-1%) in OC and 2% (0%-6%) in CC. Total complications: 0% (0%-1%) in OC and 2% (0%-6%) in CC.Conclusion: Low failure and complication rates were found in both OC and CC, with no significant difference between them in effectiveness. The CC showed a slight but significant increase in major and total complications compared to the OC. Additionally, a subtle yet significantly lower failure rate was identified in the CC.

Evaluating the efficacy of stent retriever and catheter aspiration combination in refractory cerebral venous sinus Thrombosis: A comprehensive Meta-Analysis.

BACKGROUND: Cerebral Venous Sinus Thrombosis (CVST) is a rare but potentially life-threatening condition, often associated with specific risk factors. The primary treatment for CVST is anticoagulation, but some cases progress to Refractory CVST (rCVST), requiring endovascular treatment. A combination of stent retriever and catheter aspiration is emerging as a promising technique to enhance treatment effectiveness. We conducted a systematic review and meta-analysis to assess the safety and efficacy of this approach, aiming to improve recanalization success and neurological outcomes while reducing complications in rCVST patients. METHODS: A search following PRISMA guidelines was conducted across Pubmed, Embase, Web of Science, and Cochrane databases to identify studies on the use of stent retrievers and catheter aspiration for rCVST. Pooled analysis with 95 % confidence intervals was used to assess the effects. Heterogeneity was evaluated using I2 statistics and a random-effects model was used. Complete recanalization. good clinical outcomes (mRS ≤ 2), hemorrhagic, neurological, ischemic, and total complications, poor clinical outcomes (mRS > 2), and mortality were assessed. RESULTS: A meta-analysis of five retrospective studies involving 55 patients examined outcomes in CVST. The median mean age was 40 years. Complete recanalization rate: 36 % (95 % CI: 9 % to 62 %, I2 = 90 %). Good clinical outcomes: 72 % (95 % CI: 50 % to 94 %, I2 = 76 %). Hemorrhagic complications: 2 % (95 % CI: 0 % to 8 %, I2 = 15 %). Ischemic complications: 0 % (95 % CI: 0 % to 6 %, I2 = 0 %). Neurological complications: 7 % (95 % CI: 0 % to 14 %, I2 = 0 %). Poor clinical outcomes: 26 % (95 % CI: 6 % to 46 %, I2 = 70 %). Total complications: 6 % (95 % CI: 0 % to 15 %, I2 = 10 %). Mortality rate: 5 % (95 % CI: 0 % to 13 %, I2 = 19 %). CONCLUSION: This systematic review and meta-analysis scrutinized the efficacy of combining Stent Retriever and Catheter Aspiration for rCVST. Findings highlighted varied outcomes, including recanalization rates, complications, and mortality. The dichotomy between good and poor outcomes underscores the necessity for personalized therapeutic decisions. While offering a comprehensive overview, the study emphasizes literature heterogeneity, suggesting a need for more rigorous and standardized research to optimize therapeutic strategies in clinical practice.

Good clinical outcomes and the necessity of CSF drainage in patients undergoing simultaneous biopsy and endoscopic third ventriculostomy in the region of pineal tumors: A systematic review and meta-analysis.

INTRODUCTION: Due to their delicate and deep-seated location, tumors in the pineal region of the brain pose exceptional challenges in neurosurgical management. Highly precise procedures have become crucial to address these complexities, such as the simultaneous performance of biopsy and endoscopic third ventriculostomy (ETV). Our aim was to assess the feasibility, safety, and efficacy of simultaneous biopsy and ETV for treating patients with pineal region tumors. METHODS: Medline, Embase, and Web of Science were searched for English studies from January 2000 to February 2024, following Cochrane and PRISMA guidelines. Eligible studies encompassed a minimum of four patients and examined at least one of the following outcomes: good clinical outcomes and the necessity of shunt placement. Single proportion analysis with 95% confidence intervals was conducted under a random-effects model, employing the I2 statistic to assess heterogeneity. Additionally, publication bias was evaluated using the ROBINS-I tool. RESULTS: After a meticulous selection process, eighteen studies involving 390 patients were included in the analysis. Overall, good clinical outcomes were observed in 131 out of 147 patients, representing a rate of 92 % (95 % CI: 84 % to 100 %, I2 = 62 %) through random effects analysis. Subgroup analysis showed that children exhibited a notably high rate of good clinical outcomes, reaching 100 % (95 % CI: 96 % to 100 %, I2 = 0 %). Regarding the need for shunt placement, out of the 356 patients assessed, only 39 required shunt placement, yielding a rate of 8 % (95 % CI: 4 % to 12 %, I2 = 63 %). Further sub-analyses indicated shunt requirement rates of 12 % for children and 3 % for adults. Specifically focusing on adults, data from 46 patients who underwent biopsy revealed a success rate of 84 % (95 % CI: 62 % to 100 %, I2 = 81 %). Remarkably, no major complications were reported among adults, resulting in a rate of 0 % (95 % CI: 0 % to 6 %, I2 = 0 %). Additionally, low rates of mortality related to the procedure were observed in adults, with two deaths recorded among the 46 patients analyzed, resulting in a mortality rate of 1 % (95 % CI: 0 % to 7 %, I2 = 0 %). CONCLUSION: In conclusion, our study aimed to assess the feasibility, safety, and efficacy of performing simultaneous biopsy and ETV for patients with pineal region tumors. We meticulously examined clinical aspects and patient outcomes, including good clinical outcomes, the requirement for shunt placement after ETV, biopsy success rates, mortality, and complications.

Investigating the impact of visual perspective in a motor imagery-based brain-robot interaction: A pilot study with healthy participants.

Introduction: Motor Imagery (MI)-based Brain Computer Interfaces (BCI) have raised gained attention for their use in rehabilitation therapies since they allow controlling an external device by using brain activity, in this way promoting brain plasticity mechanisms that could lead to motor recovery. Specifically, rehabilitation robotics can provide precision and consistency for movement exercises, while embodied robotics could provide sensory feedback that can help patients improve their motor skills and coordination. However, it is still not clear whether different types of visual feedback may affect the elicited brain response and hence the effectiveness of MI-BCI for rehabilitation. Methods: In this paper, we compare two visual feedback strategies based on controlling the movement of robotic arms through a MI-BCI system: 1) first-person perspective, with visual information that the user receives when they view the robot arms from their own perspective; and 2) third-person perspective, whereby the subjects observe the robot from an external perspective. We studied 10 healthy subjects over three consecutive sessions. The electroencephalographic (EEG) signals were recorded and evaluated in terms of the power of the sensorimotor rhythms, as well as their lateralization, and spatial distribution. Results: Our results show that both feedback perspectives can elicit motor-related brain responses, but without any significant differences between them. Moreover, the evoked responses remained consistent across all sessions, showing no significant differences between the first and the last session. Discussion: Overall, these results suggest that the type of perspective may not influence the brain responses during a MI- BCI task based on a robotic feedback, although, due to the limited sample size, more evidence is required. Finally, this study resulted into the production of 180 labeled MI EEG datasets, publicly available for research purposes.

Data mining framework for fatty liver disease classification in ultrasound: a hybrid feature extraction paradigm.

PURPOSE: Fatty liver disease (FLD) is an increasing prevalent disease that can be reversed if detected early. Ultrasound is the safest and ubiquitous method for identifying FLD. Since expert sonographers are required to accurately interpret the liver ultrasound images, lack of the same will result in interobserver variability. For more objective interpretation, high accuracy, and quick second opinions, computer aided diagnostic (CAD) techniques may be exploited. The purpose of this work is to develop one such CAD technique for accurate classification of normal livers and abnormal livers affected by FLD. METHODS: In this paper, the authors present a CAD technique (called Symtosis) that uses a novel combination of significant features based on the texture, wavelet transform, and higher order spectra of the liver ultrasound images in various supervised learning-based classifiers in order to determine parameters that classify normal and FLD-affected abnormal livers. RESULTS: On evaluating the proposed technique on a database of 58 abnormal and 42 normal liver ultrasound images, the authors were able to achieve a high classification accuracy of 93.3% using the decision tree classifier. CONCLUSIONS: This high accuracy added to the completely automated classification procedure makes the authors' proposed technique highly suitable for clinical deployment and usage.

Hemophilia B acquired after cadaveric liver transplantation: a case report.

Hemophilia B is a recessive hereditary disease, and manifestations result from coagulation factor IX deficiency. Although improbable, as factor IX is produced exclusively in the liver, the possibility of developing the disease after transplantation represents an infrequent but potentially morbid complication. Standard laboratory tests may be insufficient to determine the probability of transmission of this pathology. This report describes the case of a patient who developed hemophilia B after liver transplantation whose donor had no prior knowledge of the disease.

Camera-based Photoplethysmography (cbPPG) using smartphone rear and frontal cameras: an experimental study.

Non-expensive methods for measuring heart rate and oxygen saturation are of great importance in the scope of the COVID-19 outbreak to follow up on the symptoms and help to control the disease.Smartphones are widely available and their cameras can be used to acquire relevant physiological data, such as Photo-plethysmography (PPG) signals. Covering a light source and the camera sensor with a finger, it is possible to acquire the camera-based photoplethysmography (cbPPG) signal. Two methods were analyzed in this work, namely using the rear smartphone camera and the flash LED, and using the front camera and device display as a light source. The latter presents more advantages overall - in particular, greater control over the emitted light and finger detection - and better results were found when compared to a reference device.Clinical relevance- This technology allows the pervasive monitoring of the PPG signal using a standard smartphone, providing a tool to evaluate the subject's heart rate and its variability, respiration, blood oxygenation, etc.

A single stiffened nucleus alters cell dynamics and coherence in a monolayer.

Force transmission throughout a monolayer is the result of complex interactions between cells. Monolayer adaptation to force imbalances such as singular stiffened cells provides insight into the initiation of disease and fibrosis. Here, NRK-52E cells transfected with ∆50LA, which significantly stiffens the nucleus. These stiffened cells were sparsely placed in a monolayer of normal NRK-52E cells. Through morphometric analysis and temporal tracking, the impact of the singular stiffened cells shows a pivotal role in mechanoresponse of the monolayer. A method for a detailed analysis of the spatial aspect and temporal progression of the nuclear boundary was developed and used to achieve a full description of the phenotype and dynamics of the monolayers under study. Our findings reveal that cells are highly sensitive to the presence of mechanically impaired neighbors, leading to generalized loss of coordination in collective cell migration, but without seemingly affecting the potential for nuclear lamina fluctuations of neighboring cells. Reduced translocation in neighboring cells appears to be compensated by an increase in nuclear rotation and dynamic variation of shape, suggesting a "frustration" of cells and maintenance of motor activity. Interestingly, some characteristics of the behavior of these cells appear to be dependent on the distance to a ∆50LA cell, pointing to compensatory behavior in response to force transmission imbalances in a monolayer. These insights may suggest the long-range impacts of single cell defects related to tissue dysfunction.

A machine learning approach for single cell interphase cell cycle staging.

The cell nucleus is a tightly regulated organelle and its architectural structure is dynamically orchestrated to maintain normal cell function. Indeed, fluctuations in nuclear size and shape are known to occur during the cell cycle and alterations in nuclear morphology are also hallmarks of many diseases including cancer. Regrettably, automated reliable tools for cell cycle staging at single cell level using in situ images are still limited. It is therefore urgent to establish accurate strategies combining bioimaging with high-content image analysis for a bona fide classification. In this study we developed a supervised machine learning method for interphase cell cycle staging of individual adherent cells using in situ fluorescence images of nuclei stained with DAPI. A Support Vector Machine (SVM) classifier operated over normalized nuclear features using more than 3500 DAPI stained nuclei. Molecular ground truth labels were obtained by automatic image processing using fluorescent ubiquitination-based cell cycle indicator (Fucci) technology. An average F1-Score of 87.7% was achieved with this framework. Furthermore, the method was validated on distinct cell types reaching recall values higher than 89%. Our method is a robust approach to identify cells in G1 or S/G2 at the individual level, with implications in research and clinical applications.

Anti-Toxoplasma gondii and anti-Neospora caninum antibodies in sheep from Paraná state, South Brazil: prevalence and associated factors.

The aim of this study was to evaluate the seroprevalence and factors associated with the presence of anti-Toxoplasma gondii and anti-Neospora caninum antibodies in sheep from Paraná state. The detection of antibodies for T. gondii and N. caninum was performed by homemade and commercial indirect ELISA, respectively. Multiple logistic regression analysis was used to verify the factors associated with the seroprevalence. Antibodies anti-T. gondii and anti-N. caninum were observed in 42.7% and in 17.6% of the animals, respectively. The protective factors associated to seropositive were "some level of confinement" (full or semi-extensive confinement) (OR=0.53) for T. gondii and "use of skilled labor" (OR=0.64) for N. caninum. The risk factors were "presence of cats" (OR=1.75) for T. gondii and "feeding of dogs with sheep placental remains" (OR=1.79) for N. caninum. In addition, to presenting a significant and simultaneous seroprevalence for both agents (9.9% of the animals), the results also indicate that deficiencies in management and environmental sanitation, the presence of reservoirs, and types of exploitation enhance the seropositivity. Thus, studies like this might support sanitary programs and public policies for the prevention of T. gondii and N. caninum in the sheep herds of Paraná state.

Hereditary Gastric and Breast Cancer Syndromes Related to CDH1 Germline Mutation: A Multidisciplinary Clinical Review.

E-cadherin (CDH1 gene) germline mutations are associated with the development of diffuse gastric cancer in the context of the so-called hereditary diffuse gastric syndrome, and with an inherited predisposition of lobular breast carcinoma. In 2019, the international gastric cancer linkage consortium revised the clinical criteria and established guidelines for the genetic screening of CDH1 germline syndromes. Nevertheless, the introduction of multigene panel testing in clinical practice has led to an increased identification of E-cadherin mutations in individuals without a positive family history of gastric or breast cancers. This observation motivated us to review and present a novel multidisciplinary clinical approach (nutritional, surgical, and image screening) for single subjects who present germline CDH1 mutations but do not fulfil the classic clinical criteria, namely those identified as-(1) incidental finding and (2) individuals with lobular breast cancer without family history of gastric cancer (GC).

Determining transaminase activity in bacterial libraries by time-lapse imaging.

Transaminase activity was determined by time-lapse imaging using a colourimetric reaction and image analysis. A correlation between the benzaldehyde conversion and relative luminance was determined, allowing the identification of the most promising biocatalysts, the determination of kinetic parameters, and the assessment of the effect of the substrate concentration on activity.

State-of-the-art review on deep learning in medical imaging.

Deep learning (DL) is affecting each and every sphere of public and private lives and becoming a tool for daily use. The power of DL lies in the fact that it tries to imitate the activities of neurons in the neocortex of human brain where the thought process takes place. Therefore, like the brain, it tries to learn and recognize patterns in the form of digital images. This power is built on the depth of many layers of computing neurons backed by high power processors and graphics processing units (GPUs) easily available today. In the current scenario, we have provided detailed survey of various types of DL systems available today, and specifically, we have concentrated our efforts on current applications of DL in medical imaging. We have also focused our efforts on explaining the readers the rapid transition of technology from machine learning to DL and have tried our best in reasoning this paradigm shift. Further, a detailed analysis of complexities involved in this shift and possible benefits accrued by the users and developers.

Medical image noise reduction using the Sylvester-Lyapunov equation.

Multiplicative noise is often present in medical and biological imaging, such as magnetic resonance imaging (MRI), Ultrasound, positron emission tomography (PET), single photon emission computed tomography (SPECT), and fluorescence microscopy. Noise reduction in medical images is a difficult task in which linear filtering algorithms usually fail. Bayesian algorithms have been used with success but they are time consuming and computationally demanding. In addition, the increasing importance of the 3-D and 4-D medical image analysis in medical diagnosis procedures increases the amount of data that must be efficiently processed. This paper presents a Bayesian denoising algorithm which copes with additive white Gaussian and multiplicative noise described by Poisson and Rayleigh distributions. The algorithm is based on the maximum a posteriori (MAP) criterion, and edge preserving priors which avoid the distortion of relevant anatomical details. The main contribution of the paper is the unification of a set of Bayesian denoising algorithms for additive and multiplicative noise using a well-known mathematical framework, the Sylvester-Lyapunov equation, developed in the context of the Control theory.