The role of microRNAs in the pathophysiology of human central nervous system: A focus on neurodegenerative diseases

microRNAs (miRNAs) are suggested to play substantial roles in regulating the development and various physiologic functions of the central nervous system (CNS). These include neurogenesis, cell fate and differentiation, morphogenesis, formation of dendrites, and targeting non-neural mRNAs. Notably, deregulation of an increasing number of miRNAs is associated with several neurodegenerative diseases including Alzheimer's disease, Parkinson's disease, multiple sclerosis, amyotrophic lateral sclerosis and CNS tumors. They are particularly known to affect the amyloid β (Aβ) cleavage and accumulation, tau protein homeostasis, and expression of alpha-synuclein (α-syn), Parkin, PINK1, and brain-derived neurotrophic factor (BDNF) that play pivotal roles in the pathogenesis of neurodegenerative diseases. These include miR-16, miR-17-5p, miR-20a, miR-106a, miR-106b, miR-15a, miR-15b, miR-103, miR-107, miR-298, miR-328, miR-195, miR-485, and miR-29. In CNS tumors, several miRNAs, including miR-31, miR-16, and miR-21 have been identified to modulate tumorigenesis through impacting tumor invasion and apoptosis. In this review article, we have a look at the recent advances on our knowledge about the role of miRNAs in human brain development and functions, neurodegenerative diseases, and their clinical potentials.

microRNA-184 in the landscape of human malignancies: a review to roles and clinical significance

MicroRNAs (miRNAs) are a class of non-coding RNAs (ncRNAs) with a short length of 19-22 nucleotides. miRNAs are posttranscriptional regulators of gene expression involved in various biological processes like cell growth, apoptosis, and angiogenesis. miR-184 is a well-studied miRNA, for which most studies report its downregulation in cancer cells and tissues and experiments support its role as a tumor suppressor inhibiting malignant biological behaviors of cancer cells in vitro and in vivo. To exert its functions, miR-184 affects some signaling pathways involved in tumorigenesis like Wnt and β-catenin, and AKT/mTORC1 pathway, oncogenic factors (e.g., c-Myc) or apoptotic proteins, such as Bcl-2. Interestingly, clinical investigations have shown miR-184 with good performance as a prognostic/diagnostic biomarker for various cancers. Additionally, exogenous miR-184 in cell and xenograft animal studies suggest it as a therapeutic anticancer target. In this review, we outline the studies that evaluated the roles of miR-184 in tumorigenesis as well as its clinical significance.

The FeatureCloud Platform for Federated Learning in Biomedicine: Unified Approach

BACKGROUND

Machine learning and artificial intelligence have shown promising results in many areas and are driven by the increasing amount of available data. However, these data are often distributed across different institutions and cannot be easily shared owing to strict privacy regulations. Federated learning (FL) allows the training of distributed machine learning models without sharing sensitive data. In addition, the implementation is time-consuming and requires advanced programming skills and complex technical infrastructures.

OBJECTIVE

Various tools and frameworks have been developed to simplify the development of FL algorithms and provide the necessary technical infrastructure. Although there are many high-quality frameworks, most focus only on a single application case or method. To our knowledge, there are no generic frameworks, meaning that the existing solutions are restricted to a particular type of algorithm or application field. Furthermore, most of these frameworks provide an application programming interface that needs programming knowledge. There is no collection of ready-to-use FL algorithms that are extendable and allow users (eg, researchers) without programming knowledge to apply FL. A central FL platform for both FL algorithm developers and users does not exist. This study aimed to address this gap and make FL available to everyone by developing FeatureCloud, an all-in-one platform for FL in biomedicine and beyond.

METHODS

The FeatureCloud platform consists of 3 main components: a global frontend, a global backend, and a local controller. Our platform uses a Docker to separate the local acting components of the platform from the sensitive data systems. We evaluated our platform using 4 different algorithms on 5 data sets for both accuracy and runtime.

RESULTS

FeatureCloud removes the complexity of distributed systems for developers and end users by providing a comprehensive platform for executing multi-institutional FL analyses and implementing FL algorithms. Through its integrated artificial intelligence store, federated algorithms can easily be published and reused by the community. To secure sensitive raw data, FeatureCloud supports privacy-enhancing technologies to secure the shared local models and assures high standards in data privacy to comply with the strict General Data Protection Regulation. Our evaluation shows that applications developed in FeatureCloud can produce highly similar results compared with centralized approaches and scale well for an increasing number of participating sites.

CONCLUSIONS

FeatureCloud provides a ready-to-use platform that integrates the development and execution of FL algorithms while reducing the complexity to a minimum and removing the hurdles of federated infrastructure. Thus, we believe that it has the potential to greatly increase the accessibility of privacy-preserving and distributed data analyses in biomedicine and beyond.

Federated Machine Learning, Privacy-Enhancing Technologies, and Data Protection Laws in Medical Research: Scoping Review

BACKGROUND

The collection, storage, and analysis of large data sets are relevant in many sectors. Especially in the medical field, the processing of patient data promises great progress in personalized health care. However, it is strictly regulated, such as by the General Data Protection Regulation (GDPR). These regulations mandate strict data security and data protection and, thus, create major challenges for collecting and using large data sets. Technologies such as federated learning (FL), especially paired with differential privacy (DP) and secure multiparty computation (SMPC), aim to solve these challenges.

OBJECTIVE

This scoping review aimed to summarize the current discussion on the legal questions and concerns related to FL systems in medical research. We were particularly interested in whether and to what extent FL applications and training processes are compliant with the GDPR data protection law and whether the use of the aforementioned privacy-enhancing technologies (DP and SMPC) affects this legal compliance. We placed special emphasis on the consequences for medical research and development.

METHODS

We performed a scoping review according to the PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews). We reviewed articles on Beck-Online, SSRN, ScienceDirect, arXiv, and Google Scholar published in German or English between 2016 and 2022. We examined 4 questions: whether local and global models are "personal data" as per the GDPR; what the "roles" as defined by the GDPR of various parties in FL are; who controls the data at various stages of the training process; and how, if at all, the use of privacy-enhancing technologies affects these findings.

RESULTS

We identified and summarized the findings of 56 relevant publications on FL. Local and likely also global models constitute personal data according to the GDPR. FL strengthens data protection but is still vulnerable to a number of attacks and the possibility of data leakage. These concerns can be successfully addressed through the privacy-enhancing technologies SMPC and DP.

CONCLUSIONS

Combining FL with SMPC and DP is necessary to fulfill the legal data protection requirements (GDPR) in medical research dealing with personal data. Even though some technical and legal challenges remain, for example, the possibility of successful attacks on the system, combining FL with SMPC and DP creates enough security to satisfy the legal requirements of the GDPR. This combination thereby provides an attractive technical solution for health institutions willing to collaborate without exposing their data to risk. From a legal perspective, the combination provides enough built-in security measures to satisfy data protection requirements, and from a technical perspective, the combination provides secure systems with comparable performance with centralized machine learning applications.

Evaluation of in vivo lithium chloride effects as a GSK3-β inhibitor on human adipose derived stem cells differentiation into oligodendrocytes and re-myelination in an animal model of multiple sclerosis

BACKGROUND

The application of neuroprotective agents in combination with stem cells is considered a potential effective treatment for multiple sclerosis (MS). Therefore, the effects of lithium chloride as a neuroprotective agent and a GSK3-β inhibitor were evaluated in combination with human adipose derived stem cells on re-myelination, oligodendrocyte differentiation, and functional recovery.

METHODS

After inducing a mouse model of MS and proving it by the hanging wire test, the mice were randomly assigned to five experimental groups: Cup, Sham, Li, hADSC, and Li + hADSC. Additionally, a control group with normal feeding was considered. Finally, toluidine blue staining was carried out to estimate the level of myelination. Furthermore, immunofluorescent staining was used to evaluate the mean of OLIG2 and MOG positive cells. The mRNA levels of β-Catenin, myelin and oligodendrocyte specific genes were determined via the Real-Time PCR.

RESULTS

The results of the hanging wire test and toluidine blue staining showed a significant increase in myelin density and improvements in motor function in groups, which received lithium and stem cells, particularly in the Li + hADSC group compared with the untreated groups (P < 0.01). Moreover, immunostaining results indicated that the mean percentages of MOG and OLIG2 positive cells were significantly higher in the Li + hADSC group than in the other groups (P < 0.01). Finally, gene expression studies indicated that the use of lithium could increase the expression of β-Catenin, myelin and oligodendrocyte specific genes.

CONCLUSION

The use of Lithium Chloride can increase stem cells differentiation into oligodendrocytes and improve re-myelination in MS.

Valproic acid effects on human adipose-derived stem cell differentiation into oligodendrocytes and improved remyelination in a mouse model of Multiple Sclerosis

Valproic acid (VPA), a neuroprotective agent and inhibitor of GSK3-β, along with human Adipose-Derived Stem Cells (hADSCs) have been proposed to be potential therapeutic agents for neurodegenerative disorders. In the present study, we have assessed the effects of VPA alone or in combination with hADSCs on oligodendrocyte differentiation, remyelination, and functional recovery in a mouse model of Multiple Sclerosis (MS). These MS-model mice were randomly divided into cuprizone, sham, VPA, hADSC, and VPA/hADSC groups, with 10 mice considered a control group (healthy mice). The hanging wire test was used to measure motor behavior. To estimate the level of myelination, we performed toluidine blue staining and immunofluorescent staining for OLIG2 and MOG-positive cells. Real-time PCR was used to evaluate the expression of β-catenin, human and mouse Mbp, Mog, and Olig2 genes. Remyelination and motor function improved in mice receiving VPA, hADSCs, and especially VPA/hADSCs compared to the Cup and Sham groups (P < 0.01). Additionally, the number of MOG and OLIG2 positive cells significantly increased in the VPA/hADSCs group compared to the Cup and Sham groups (P < 0.01). The expression of β-catenin, myelin and the other oligodendrocyte-specific genes was significantly higher in the VPA recipient groups. Valproic acid can enhance the differentiation of stem cells into oligodendrocytes, making it a potential candidate for MS treatment.

Privacy-aware multi-institutional time-to-event studies

Clinical time-to-event studies are dependent on large sample sizes, often not available at a single institution. However, this is countered by the fact that, particularly in the medical field, individual institutions are often legally unable to share their data, as medical data is subject to strong privacy protection due to its particular sensitivity. But the collection, and especially aggregation into centralized datasets, is also fraught with substantial legal risks and often outright unlawful. Existing solutions using federated learning have already demonstrated considerable potential as an alternative for central data collection. Unfortunately, current approaches are incomplete or not easily applicable in clinical studies owing to the complexity of federated infrastructures. This work presents privacy-aware and federated implementations of the most used time-to-event algorithms (survival curve, cumulative hazard rate, log-rank test, and Cox proportional hazards model) in clinical trials, based on a hybrid approach of federated learning, additive secret sharing, and differential privacy. On several benchmark datasets, we show that all algorithms produce highly similar, or in some cases, even identical results compared to traditional centralized time-to-event algorithms. Furthermore, we were able to reproduce the results of a previous clinical time-to-event study in various federated scenarios. All algorithms are accessible through the intuitive web-app Partea (https://partea.zbh.uni-hamburg.de), offering a graphical user interface for clinicians and non-computational researchers without programming knowledge. Partea removes the high infrastructural hurdles derived from existing federated learning approaches and removes the complexity of execution. Therefore, it is an easy-to-use alternative to central data collection, reducing bureaucratic efforts but also the legal risks associated with the processing of personal data to a minimum.

Flimma: a federated and privacy-aware tool for differential gene expression analysis

Aggregating transcriptomics data across hospitals can increase sensitivity and robustness of differential expression analyses, yielding deeper clinical insights. As data exchange is often restricted by privacy legislation, meta-analyses are frequently employed to pool local results. However, the accuracy might drop if class labels are inhomogeneously distributed among cohorts. Flimma ( https://exbio.wzw.tum.de/flimma/ ) addresses this issue by implementing the state-of-the-art workflow limma voom in a federated manner, i.e., patient data never leaves its source site. Flimma results are identical to those generated by limma voom on aggregated datasets even in imbalanced scenarios where meta-analysis approaches fail.

The effects of high fructose fruits and honey on the serum level of metabolic factors and nonalcoholic fatty liver disease

Introduction

The effect of the natural sources of fructose such as high fructose fruits and honey on the risk of fatty liver is still challenging. This study aimed to compare the effect of fructose, high fructose fruits, and honey on the metabolic factors and non-alcoholic fatty liver disease (NAFLD).

Methods

Forty-four rats were divided into four groups including normal diet group, high fructose group (HF), high fructose fruits group (HFF), and honey group (HO). After 120 days of intervention, the levels of insulin resistance, hepatic enzyme, and lipid profile were measured. Also, the expression levels of the acetyl-coA carboxylase (ACC), sterol regulatory element-binding protein 1c (SREBP-1c), Interleukin 6 (IL-6), and transforming growth factor-beta (TGF-β) genes were assessed. In addition, a histopathologic assessment was performed on liver tissues.

Results

Insulin resistance (IR) increased significantly in the HF, HFF, and HO groups (All P < 0.05). The levels of liver enzymes was significantly increased only in the group receiving the HF regimen (P < 0.01). A significant decrease in total cholesterol and HDL-C (high density lipoprotein cholesterol) levels was found in HO group compared to the control group (P < 0.05). The expression levels of ACC and SREBP-1c genes in HF, HFF, and HO groups were significantly higher than the control group (All P < 0.05). The HF group had a greater increase in the level of gene expression of IL-6 and TGF-β (All P < 0.05). Histopathological assessment did not find any changes in fatty liver formation and inflammatory damage.

Conclusion

Consumption of fructose-rich honey and fruits improved the status of inflammatory markers and liver enzymes compared with the industrial fructose-rich products.

P–062 Annexin-V MACS method could be a good choice for sperm selection with high PLCZ1 expression and high blastocyst rate in high DFI male factor

Study question

What effect does Annexin-V MACS method have on sperm selection by pLCZ1 expression and blastocyst rate in male DNA fragmentation?

Summary answer

AnnexinV-MACS method could be a good choice for sperm selection with high pLCZ1 expression and high blastocyst rate in high DNA fragmentation male factor.

What is known already

Sperm selection based on morphology and motility in ART techniques, is not enough for choosing the best sperm especially in male factor patients. In Annexin-V magnetic activated cell sorting (MACS) technique, apoptotic sperm are separated from non-apoptotic one by negative selection. So, this method can improved quality of compaction rate in embryo. PLCζ is oocyte activating factors that it starts oscillations of calcium ca2+ in oocyte and it has a significant effect on fertilization and implantation.

Study design, size, duration

Semen samples from 30 male factor infertile couples with high DFI (DFI&gt;30%) were selected and divided into two group (control and experimental) in each patient.

Participants/materials, setting, methods

Control was washed with DGC and experimental one was selected by MACS-DGC. Retrieved eggs in each patient, were divided in 2. Both group were injected by DGC and MACS respectively. Semen parameters and DFI (SCD test) were analyzed before and after processing. After ICSI, rate of fertilization, embryo development and blastocyst formation were evaluated. Real time PCR evaluate expression of PLCζ. Comparison between results of two groups was assessed by SPSS analysis.

Main results and the role of chance

Results showed that, sperm motility and morphology after MACS method (45%, 1.7%) was significantly higher than DGC method (40%, 1.1%) and before washing (35%, 0.9%). Percent of DFI in MACS group (36%) was significantly decreased compared to DGC (45%) and primitive group (55%). The number of oocytes were injected in DGC group was 93 and in MACS group was 111. Fertilization rate in both groups was almost the same (72.07% in MACS vs 73.11 in DGC). Rate of day 3 embryo with good grade in MACS group (72. 5%) was significantly higher than DGC (51.47%) (P &lt; 0.05). The blastocyst rate in MACS-DGC group (69.69%) was significantly increased compared to DGC group (48%). PLCζ gene expression in MACS-DGC was significantly higher than DGC group (p-value=0.046).

Limitations, reasons for caution

This experiment was performed invivo.

Wider implications of the findings: Sperm selection by MACS-DGC method can improve sperm motility, morphology and reduce sperm DFI. No significant difference was observed in fertilization rate, but percent of high-quality embryo on days 3 and 5 was significantly higher by this method,also it can be suggested as a good choice for patients with highDF.

Trial registration number

Not applicable

The effect of applied electric field on the micromorphology of Pt nanoparticles synthesized by laser ablation

In the present study, laser ablation technique (Nd:YAG) has been applied to synthesize platinum nanoparticles (NPs). Also, the effect of applied electric field on the physical, structural, and morphological properties of Pt NPs has been investigated during the nanosecond pulsed laser ablation of platinum. Based on the results extracted from TEM and scanning electron microscopy images, the formation of high percentage of NPs with spherical shape is demonstrated in all samples. The increase of applied electric field creates few rectangular, hexagonal, and rhombic NPs with the average size decreased from 20 to 9 nm. The significant influence of increasing electric field is also observed in UV-vis spectra by appearing the blue shift of the localized surface plasmon resonance peak. The UV-vis spectra also confirm the metallic nature of Pt NPs and the existence of inhomogeneous-sized particles and the coagulation of particle because of the long tail in higher wavelengths. In addition, atomic force microscopy images have been analyzed through MountainsMap Premium program and fractal dimension. As can be seen, increasing the applied electric field make the surface more irregular and the maximum value of D_f reveals the most irregular topography for sample with 50 V/cm electric field. Finally, the bending and stretching frequencies of the functional bending groups connected to the NPs surface have been characterized by Fourier transform infrared spectroscopy. Electrical field-assisted laser ablation in liquids method allows a better control of the size, morphology, structure, and chemical composition of nanoparticles.

Evaluation of Edaravone effects on the differentiation of human adipose derived stem cells into oligodendrocyte cells in multiple sclerosis disease in rats

AIMS

Among all the treatments for Multiple Sclerosis, stem cell transplantation, such as ADSCs, has attracted a great deal of scientific attention. On the other hand, Edaravone, as an antioxidant component, in combination with stem cells, could increase the survival and differentiation potential of stem cells.

MAIN METHODS

42 rats were divided into: Control, Cuprizone (CPZ), Sham, Edaravone (Ed), hADSCs, and Ed/hADSCs groups. Following induction of cuprizone, induced MS model, behavioral tests were designed to evaluate motor function during. Luxal fast blue staining was done to measure the level of demyelination and remyelination. Immunofluorescent staining was used to evaluate the amount of MBP, OLIG2, and MOG proteins. The mRNA levels of human MBP, MOG, and OLIG2 and rat Mbp, Mog, and Olig2 were determined via RT-PCR.

KEY FINDINGS

Flow cytometry analysis exhibited that the extracted cells were positive for CD73 (93.8 ± 3%) and CD105 (91.6 ± 3%), yet negative for CD45 (2.06 ± 0.5%). Behavioral tests, unveiled a significant improvement in the Ed (P < 0.001), hADSCs (P < 0.001), and Ed/hADSCs (P < 0.001) groups compared to the others. In the Ed/hADSCs group, the myelin density was significantly higher than that in the Ed treated and hADSCs treated groups (P < 0.01). Edaravone and hADSCs increased the expression of Mbp, Mog, and Olig2 genes in the cuprizone rat models. Moreover, significant differences were seen between the Ed treated and hADSCs treated groups and the Ed/hADSCs group (P < 0.05 for Mbp and Olig2 and P < 0.01 for Mog).

SIGNIFICANCE

Edaravone in combination with hADSCs reduced demyelination and increased oligodendrogenesis in the cuprizone rat models.

Increased risk of coronary perforation during percutaneous intervention of myocardial bridge: What histopathology says

Introduction: Myocardial bridge (MB) is a segment of a major epicardial coronary artery that goes intramurally under a bridge of overlying myocardium. Complications have been reported during or after stent implantation particularly coronary perforation. The aim of this study was to determine histological differences between proximal left anterior descending artery (LAD) and the tunneled segment that may have a possible role in increased risk of coronary artery perforation during percutaneous coronary intervention.

Methods: Twenty specimens of MB were obtained from dissection of 45 cadavers. Sections were stained using hematoxylin and eosin (H&E), and trichrome methods. The proximal section and the tunneled artery were compared with a normal sample in terms of the characteristics of a muscle artery.

Results: The findings of this study showed an MB prevalence of 51%, as 23 out of the 45 examined cadavers were discovered to be afflicted by the MB. The intima layer in the suffering artery had gone through significant hypertrophy, while it had remained thin in the tunneled artery section. The epithelial cells under the bridge were spindle-shaped, while they were polygonal in the proximal section. In the myocardium the nuclei of the muscle fibers in the MB section were smaller than the normal section. Adventitial layer was almost normal.

Conclusion: The histopathological differences between MB and proximal part of vessel combined with small vessel diameter in the tunneled segment can explain the high incidence of the LAD rupture and perforation in the section under the bridge.

TTY2 genes deletions as genetic risk factor of male infertility

Y chromosome has a number of genes that are expressed in testis and have a role in spermatogenesis. TTY2L12A and TTY2L2A are the members of testis transcript Y2 (TTY2) that are Y linked multi-copy gene families, located on Yp11 and Yq11 loci respectively. The aim of this study was to investigate frequency of TTY2L12A and TTY2L2A deletions in azoospermic patients compared with fertile males. This study was performed on 45 infertile males with idiopathic azoospermia without any AZF micro deletions (group A), 33 infertile males with azoospermia which do not screened for AZF micro deletions (group B) and 65 fertile males (group C), from October 2013 to April 2015 in west of Iran. Polymerase chain reaction (PCR) method was used for detection of TTY2L12A and TTY2L2A gene deletions in studied groups. No deletions were detected in normal fertile males of group C. 1 out of 45 azoospermic males of group A (2.22%) and 3 out of 33 azoospermic males of group B (9.09%) had TTY2L2A deletion (p= 0.409 and p= 0.036 respectively), also 1 out of 45 azoospermic males of group A (2.22%) and 4 out of 33 azoospermic males of group B (12.12%) had TTY2L12A deletion (p= 0.409 and p= 0.011 respectively).  None of azoospermic males in Group A and B had deletions in both genes. Our data showed significant correlation between non-obstructive azoospermia and TTY2L12A and TTY2L2A deletions. Thus, it seems that TTY2L12A and TTY2L2A deletions can consider as one of the genetic risk factors for non-obstructive azoospermia.

Analysis of equality in Iranian household healthcare payments during Iran's fourth development program

Introduction

Today, the provision of healthcare should be efficient and equitable to achieve the health system’s goals. The aim of this study was to survey equality in healthcare expenditures and its effects on income redistribution.

Methods

This study was a descriptive-analysis, cross-sectional study that was conducted with data obtained from the Statistical Center of Iran (SCI) during 2006 and 2011. The source population and study population were the urban and rural residents of Iran and their households’ income and expenditures on health. The analysis was based on annually aggregated data from all provinces relative to their share of the total population. The data were collected using a pre-tested checklist consisting of two sections. The first section was used to retrieve data about total gross non-food expenditures of households. The second section retrieved out-of-pocket payments for healthcare. The data that were collected were analyzed using a Microsoft Excel spreadsheet. The Kakwani index was used to measure the extent of the deviation from equity. The redistributive effect of healthcare costs was considered as the impact of healthcare payments on households’ income distribution.

Results

The overall Kakwani index during the fourth development program for urban households was progressive (OKI = 0.013), but it was regressive for rural households (OKI = −0.012). Healthcare payments had a negative effect on income redistribution in urban areas during the entire period of the study, and they had a positive effect in rural areas, except for the years 2010 and 2011, for which the effects were negative and non-existent, respectively.

Conclusion

By regarding the regressive Kakwani index and the negative effect of healthcare expenditures on income redistribution in some years, the government can use health grants, such as increasing health facilities and supplementary insurance, to increase the ability of households to deal with the cost of developing a remedy and reducing health inequalities.

An Exploration of the Maternal Experiences of Breast Engorgement and Milk Leakage after Perinatal ‎Loss‎

Introduction and Purpose:

Perinatal loss is one of the toughest events of life. Physiological milk secretion after perinatal loss adds to complicacy of the hardships of the event. The present study is aimed at exploring women’s experience with breast problems and milk leakage after perinatal loss.

Methods:

The Study was carried out through explorative quality approach with 18 participants. Sampling method was purposeful and selecting the participants from widest variety was ensured. Data gathering was through deep semi-structured interview and data analyses were done by conventional content analysis. Reliability and validity of the data were ensured by collecting data from a wide range of participants and frequent revisions.

Findings:

Data analysis indicated four themes including beyond pain, longing being mother, insufficiency of provided information and coping Strategies, and beliefs and values regarding milk leakage and breast engorgement.

Conclusion:

The findings suggested that health care givers needed to inform the patients about probability milk leakage and breast engorgement and remedies to reduce pains and problems of breast engorgement.

Pancreatic Lymphangioma as a Rare Pancreatic Mass: A Case Report

Introduction

Cystic lymphangiomas of abdomen has mostly involved mesentery and retro peritoneum that should be considered as a differential diagnosis of abdominal masses. Pancreatic lymphangiomas were extremely rare that should be differentiated from neoplastic pancreatic cysts. Patients have commonly presented with epigastric pain and a relevant palpable epigastric mass.

Case Presentation

A 65-year-old lady who has presented with epigastric pain, then during investigations, a cystic tumor which located in the tail of pancreas, has found. Whereas definite diagnosis of tumor with routine procedures was impossible, the tumor has completely resected by distal pancreatectomy and splenectomy. Pathology and IHC was suggestive of benign lymphangioma.

Conclusions

According to this presentation diagnosis of cystic lymphangioma of the tail of pancreas should be considered as a differential diagnosis of pancreatic cystic lesions and complete excision has been the treatment of choice.

Relationship Between Shift Work and Personality Traits of Nurses and Their Coping Strategies

BACKGROUND & OBJECTIVE

Because of social progress, population growth, industrialization, and the requirements of some jobs, a significant percentage of employees are working in shifts. Shift work is considered a threat to health that could have unfavorable effects on various aspects of human life. This study investigated the relationship between shift work and the personality traits of nurses and their coping strategies in a selection of non-governmental hospitals in Tehran in 2014.

METHODS

This applied cross-sectional descriptive research employed the Standard Shift work Index and Eysenck Personality Questionnaire (EPQ) which, after confirmation of its validity and reliability (Cronbach's alpha 0.73), were distributed among 305 nurses from 6 non-governmental hospitals in Tehran selected through cluster random sampling. Data was analyzed in two statistical levels: descriptive and inferential.

RESULTS

Results revealed that 43.6% of the nurses participating in the study were introverted and 56.4% were extroverted. There are significant relationships between age and physical health (P=0.008), sex and physical health (P=0.015), educational level and physical health (P=0.014), sex and cognitive, somatic anxiety (P=0.006), age and social-family status (P=0.001), marital status and social-family status (P=0.001), having a second job and social-family status (P=0.001), educational level and sleep and fatigue (P=0.002), work experience and coping strategies (P=0.044), and sleep and fatigue and personality traits (P=0.032).

CONCLUSION

Complying with the standards of working hours for nurses and avoiding overtime when scheduling, especially for nurses with more work experience, can prevent the severe complications of shift work, enhance health, and ultimately enhance the quality of care. By improving the physical, psychological, and social health of nurses, the quality of patient care can be expected to improve, too.

A two-dimensional matrix correction for off-axis portal dose prediction errors

PURPOSE

This study presents a follow-up to a modified calibration procedure for portal dosimetry published by Bailey et al. ["An effective correction algorithm for off-axis portal dosimetry errors," Med. Phys. 36, 4089-4094 (2009)]. A commercial portal dose prediction system exhibits disagreement of up to 15% (calibrated units) between measured and predicted images as off-axis distance increases. The previous modified calibration procedure accounts for these off-axis effects in most regions of the detecting surface, but is limited by the simplistic assumption of radial symmetry.

METHODS

We find that a two-dimensional (2D) matrix correction, applied to each calibrated image, accounts for off-axis prediction errors in all regions of the detecting surface, including those still problematic after the radial correction is performed. The correction matrix is calculated by quantitative comparison of predicted and measured images that span the entire detecting surface. The correction matrix was verified for dose-linearity, and its effectiveness was verified on a number of test fields. The 2D correction was employed to retrospectively examine 22 off-axis, asymmetric electronic-compensation breast fields, five intensity-modulated brain fields (moderate-high modulation) manipulated for far off-axis delivery, and 29 intensity-modulated clinical fields of varying complexity in the central portion of the detecting surface.

RESULTS

Employing the matrix correction to the off-axis test fields and clinical fields, predicted vs measured portal dose agreement improves by up to 15%, producing up to 10% better agreement than the radial correction in some areas of the detecting surface. Gamma evaluation analyses (3 mm, 3% global, 10% dose threshold) of predicted vs measured portal dose images demonstrate pass rate improvement of up to 75% with the matrix correction, producing pass rates that are up to 30% higher than those resulting from the radial correction technique alone. As in the 1D correction case, the 2D algorithm leaves the portal dosimetry process virtually unchanged in the central portion of the detector, and thus these correction algorithms are not needed for centrally located fields of moderate size (at least, in the case of 6 MV beam energy).

CONCLUSION

The 2D correction improves the portal dosimetry results for those fields for which the 1D correction proves insufficient, especially in the inplane, off-axis regions of the detector. This 2D correction neglects the relatively smaller discrepancies that may be caused by backscatter from nonuniform machine components downstream from the detecting layer.

EPID dosimetry for pretreatment quality assurance with two commercial systems

This study compares the EPID dosimetry algorithms of two commercial systems for pretreatment QA, and analyzes dosimetric measurements made with each system alongside the results obtained with a standard diode array. 126 IMRT fields are examined with both EPID dosimetry systems (EPIDose by Sun Nuclear Corporation, Melbourne FL, and Portal Dosimetry by Varian Medical Systems, Palo Alto CA) and the diode array, MapCHECK (also by Sun Nuclear Corporation). Twenty-six VMAT arcs of varying modulation complexity are examined with the EPIDose and MapCHECK systems. Optimization and commissioning testing of the EPIDose physics model is detailed. Each EPID IMRT QA system is tested for sensitivity to critical TPS beam model errors. Absolute dose gamma evaluation (3%, 3 mm, 10% threshold, global normalization to the maximum measured dose) yields similar results (within 1%-2%) for all three dosimetry modalities, except in the case of off-axis breast tangents. For these off-axis fields, the Portal Dosimetry system does not adequately model EPID response, though a previously-published correction algorithm improves performance. Both MapCHECK and EPIDose are found to yield good results for VMAT QA, though limitations are discussed. Both the Portal Dosimetry and EPIDose algorithms, though distinctly different, yield similar results for the majority of clinical IMRT cases, in close agreement with a standard diode array. Portal dose image prediction may overlook errors in beam modeling beyond the calculation of the actual fluence, while MapCHECK and EPIDose include verification of the dose calculation algorithm, albeit in simplified phantom conditions (and with limited data density in the case of the MapCHECK detector). Unlike the commercial Portal Dosimetry package, the EPIDose algorithm (when sufficiently optimized) allows accurate analysis of EPID response for off-axis, asymmetric fields, and for orthogonal VMAT QA. Other forms of QA are necessary to supplement the limitations of the Portal Vision Dosimetry system.

SU-E-J-114: Web-Browser Medical Physics Applications Using HTML5 and Javascript

PURPOSE

Since 2010, there has been a great attention about HTML5. Application developers and browser makers fully embrace and support the web of the future. Consumers have started to embrace HTML5, especially as more users understand the benefits and potential that HTML5 can mean for the future.Modern browsers such as Firefox, Google Chrome, and Safari are offering better and more robust support for HTML5, CSS3, and JavaScript. The idea is to introduce the HTML5 to medical physics community for open source software developments. The benefit of using HTML5 is developing portable software systems.

METHODS

The HTML5, CSS, and JavaScript programming languages were used to develop several applications for Quality Assurance in radiation therapy. The canvas element of HTML5 was used for handling and displaying the images, and JavaScript was used to manipulate the data. Sample application were developed to: 1. analyze the flatness and symmetry of the radiotherapy fields in a web browser, 2.analyze the Dynalog files from Varian machines, 3. visualize the animated Dynamic MLC files, 4. Simulation via Monte Carlo, and 5. interactive image manipulation.

RESULTS

The programs showed great performance and speed in uploading the data and displaying the results. The flatness and symmetry program and Dynalog file analyzer ran in a fraction of second. The reason behind this performance is using JavaScript language which is a lower level programming language in comparison to the most of the scientific programming packages such as Matlab. The second reason is that JavaScript runs locally on client side computers not on the web-servers.

CONCLUSIONS

HTML5 and JavaScript can be used to develop useful applications that can be run online or offline on different modern web-browsers. The programming platform can be also one of the modern web-browsers which are mostly open source (such as Firefox).

Proliferation and differentiation potential of cryopreserved human skin-derived precursors

OBJECTIVES

Skin-derived precursors are recognized to be a potentially autologous and accessible source of neural precursor cells for drug screening or cell-based treatments, in many neurological disorders. Thus, it is necessary to investigate appropriate methods for cryopreservation of such human skin-derived precursors (hSKPs). The aim of this study was to evaluate different cryopreservation techniques for retention of hSKPs to discover an optimized protocol.

MATERIALS AND METHODS

We cryopreserved hSKPs treated with 0%, 10%, 20%, 30% and 40% foetal bovine serum (FBS) and three concentrations of dimethylsulphoxide (DMSO) 5%, 10% and 15%, with two different storage periods in liquid nitrogen (2 days: short-term storage; and 2 months: long-term storage). Then, we assessed survival and proliferation levels of the cells after freeze-thaw processes, by viability measurement and colony-forming assay. For detecting hSKPs, we used immunocytochemistry and RT-PCR assessments.

RESULTS

Our findings indicated that hSKPs cryopreserved in 5% DMSO without FBS, had better survival and proliferation potentials compared to other working formulations. With various concentrations of cryoprotectants over different time periods, hSKPs retained their differentiation potentiality and were able to differentiate into neurons (NFM and βΙΙΙ tubulin-positive), glial cells (GFAP-positive) and smooth muscle cells (SMA-positive).

CONCLUSIONS

  Results revealed that in only 5% DMSO, hSKPs could be cryopreserved for long-term storage with considerable survival and proliferation levels, without losing multipotency.

Effect of surface waves on radiotherapy dosimetric measurements in water tanks

The effect of surface waves, generated by moving the scanning arms in water phantoms, on radiation dosimetry is studied. It is shown that in large water tanks, high arm speeds can result in dosimetric errors of up to 5%. The measurements that are started after damping the water waves can result in about a 50% improvement in accuracy of measurements. It is shown that the water surfaces at the start of the measurements have high fluctuations that transform to a steady phase by elapsing time.

Optimization of beam angles for intensity modulated radiation therapy treatment planning using genetic algorithm on a distributed computing platform

Planning intensity modulated radiation therapy (IMRT) treatment involves selection of several angle parameters as well as specification of structures and constraints employed in the optimization process. Including these parameters in the combinatorial search space vastly increases the computational burden, and therefore the parameter selection is normally performed manually by a clinician, based on clinical experience. We have investigated the use of a genetic algorithm (GA) and distributed-computing platform to optimize the gantry angle parameters and provide insight into additional structures, which may be necessary, in the dose optimization process to produce optimal IMRT treatment plans. For an IMRT prostate patient, we produced the first generation of 40 samples, each of five gantry angles, by selecting from a uniform random distribution, subject to certain adjacency and opposition constraints. Dose optimization was performed by distributing the 40-plan workload over several machines running a commercial treatment planning system. A score was assigned to each resulting plan, based on how well it satisfied clinically-relevant constraints. The second generation of 40 samples was produced by combining the highest-scoring samples using techniques of crossover and mutation. The process was repeated until the sixth generation, and the results compared with a clinical (equally-spaced) gantry angle configuration. In the sixth generation, 34 of the 40 GA samples achieved better scores than the clinical plan, with the best plan showing an improvement of 84%. Moreover, the resulting configuration of beam angles tended to cluster toward the patient's sides, indicating where the inclusion of additional structures in the dose optimization process may avoid dose hot spots. Additional parameter selection in IMRT leads to a large-scale computational problem. We have demonstrated that the GA combined with a distributed-computing platform can be applied to optimize gantry angle selection within a reasonable amount of time.

Using an EPID for patient-specific VMAT quality assurance

PURPOSE

A patient-specific quality assurance (QA) method was developed to verify gantry-specific individual multileaf collimator (MLC) apertures (control points) in volumetric modulated arc therapy (VMAT) plans using an electronic portal imaging device (EPID).

METHODS

VMAT treatment plans were generated in an Eclipse treatment planning system (TPS). DICOM images from a Varian EPID (aS1000) acquired in continuous acquisition mode were used for pretreatment QA. Each cine image file contains the grayscale image of the MLC aperture related to its specific control point and the corresponding gantry angle information. The TPS MLC file of this RapidArc plan contains the leaf positions for all 177 control points (gantry angles). In-house software was developed that interpolates the measured images based on the gantry angle and overlays them with the MLC pattern for all control points. The 38% isointensity line was used to define the edge of the MLC leaves on the portal images. The software generates graphs and tables that provide analysis for the number of mismatched leaf positions for a chosen distance to agreement at each control point and the frequency in which each particular leaf mismatches for the entire arc.

RESULTS

Seven patients plans were analyzed using this method. The leaves with the highest mismatched rate were found to be treatment plan dependent.

CONCLUSIONS

This in-house software can be used to automatically verify the MLC leaf positions for all control points of VMAT plans using cine images acquired by an EPID.

Applying graphics processor units to Monte Carlo dose calculation in radiation therapy

We investigate the potential in using of using a graphics processor unit (GPU) for Monte-Carlo (MC)-based radiation dose calculations. The percent depth dose (PDD) of photons in a medium with known absorption and scattering coefficients is computed using a MC simulation running on both a standard CPU and a GPU. We demonstrate that the GPU's capability for massive parallel processing provides a significant acceleration in the MC calculation, and offers a significant advantage for distributed stochastic simulations on a single computer. Harnessing this potential of GPUs will help in the early adoption of MC for routine planning in a clinical environment.