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Aims/hypothesis Beta cells control glucose homeostasis via regulated production and secretion of insulin. This function arises from a highly specialised gene expression programme that is established during development and then sustained, with limited flexibility, in terminally differentiated cells. Dysregulation of this programme is seen in type 2 diabetes but mechanisms that preserve gene expression or underlie its dysregulation in mature cells are not well resolved. This study investigated whether methylation of histone H3 lysine 4 (H3K4), a marker of gene promoters with unresolved functional importance, is necessary for the maintenance of mature beta cell function. Methods Beta cell function, gene expression and chromatin modifications were analysed in conditional Dpy30 knockout mice, in which H3K4 methyltransferase activity is impaired, and in a mouse model of diabetes. Results H3K4 methylation maintains expression of genes that are important for insulin biosynthesis and glucose responsiveness. Deficient methylation of H3K4 leads to a less active and more repressed epigenome profile that locally correlates with gene expression deficits but does not globally reduce gene expression. Instead, developmentally regulated genes and genes in weakly active or suppressed states particularly rely on H3K4 methylation. We further show that H3K4 trimethylation (H3K4me3) is reorganised in islets from the Leprdb/db mouse model of diabetes in favour of weakly active and disallowed genes at the expense of terminal beta cell markers with broad H3K4me3 peaks. Conclusions/interpretation Sustained methylation of H3K4 is critical for the maintenance of beta cell function. Redistribution of H3K4me3 is linked to gene expression changes that are implicated in diabetes pathology. Graphical abstract

Plant-derived nanoparticles (PDNPs) are naturally occurring exosome-like nanovesicles derived from dietary plants containing key plant bioactives. Ginger-derived PDNPs have a therapeutic effect on alcohol-induced liver injury, inflammatory bowel disease, and colon cancer. PDNPs are conventionally purified by differential ultracentrifugation, a technique not amenable for scale up. We have recently developed a polyethylene glycol (PEG) 6000-based method for cost-effective purification of ginger PDNPs, with comparable efficiency to differential ultracentrifugation (Sci. Rep. 2020, 10 (1), 4456.). Herein, we report a 4-5-fold higher ginger PDNP recovery when PEG precipitation was carried out in low pH conditions (pH 4 and 5). Low pH-derived ginger PDNPs were smaller in size without an overt change in zeta potential. The spontaneous intracellular entry and protection against oxidative stress in A431 cells were similar between ginger PDNPs purified under low, neutral, and alkaline pH. Low-pH purified ginger PDNPs had higher levels of total polyphenolic content compared to PDNPs purified under neutral and alkaline pH. Recently, ginger PDNP-derived microRNAs have been shown to exhibit cross-kingdom regulation by targeting human, gut microbiome, and viral transcripts. Using qRT-PCR, we also verified the presence of miRNAs that were predicted to target SARS-CoV-2 in ginger PDNPs purified under low pH. Thus, we have developed a method to purify ginger PDNPs in high yields by using low-pH conditions without affecting the major bioactive contents of PDNPs.

Osteoporosis is a ubiquitous and chronic process that affects an increasing number of people each year. Various forms of treatment are currently used including bisphosphonates which have been linked to atypical fractures of the femur. We present a case series of eight osteoporosis patients who developed atypical femoral fractures, while on bisphosphonate therapy. This pictorial review aims to increase awareness of bisphosphonate-related atypical fractures, discuss the current literature recommendations, and provide clear learning points from each case-based discussion.

Background Suspected scaphoid fracture (SF) after a fall on an outstretched hand is a common presentation in the emergency department. Magnetic resonance imaging (MRI) or computed tomography (CT) has been suggested to assist in the diagnosis or exclusion of SF. Purpose To compare MRI and CT at diagnosing occult SFs. Material and Methods We routinely perform CT scans in patients with clinically suspected occult SF, after 7–10 days of injury following two negative radiographs. All eligible patients with a clinically suspected SF, but negative radiographs and a negative CT, underwent an MRI scan to assess further for evidence of occult fracture. Results A total of 100 patients were included in our study. MRI showed fractures in 16% of the time (in 15 patients) when plain radiographs and CT did not. Of these fractures, 8% were SFs. In addition to fractures, 10% had bone bruising. A total of 25% of patients with fractures and bone bruising were referred to the hand surgery team for further follow-up. Conclusion The study demonstrated that MRI would identify a radiographically occult SF more often than CT. This supports NICE guidelines which recommend MRI as the best early diagnostic tool for occult SFs.

We present a case of split and partially entwined sciatic nerve by a femoral prosthesis following closed reduction of a dislocated hip replacement. This complication is very rare and there are only few cases reported in the literature, with even less accompanied by supporting MRI. We present MRI features of a split and partially entwined sciatic nerve around a hip prosthesis.

The spine is a complex structure composed of different tissues with a wide range of clinical pathologies. There are multiple imaging modalities available at our disposal to image the spine. This article will present several common pathologies and how different imaging modalities have their respective roles in clinching the right diagnosis and aiding subsequent management.

A stripline fed tapered slot antenna (STSA) with integral coupler operating as an active array element over 1.5 octave bandwidth is presented. The proposed STSA with integral coupler features wideband transition which allows a direct 50 stripline feed and enables the coupler to be integrated along with the feed. The coupler helps in taking a sample of signal for online performance monitoring and active phased array calibration. The measured results of antenna element have exhibited good radiation pattern performance with low cross-polarisation in principal plane and low beam squint. Using this, a 16-element H-plane linear phased array antenna designed for the frequency range of 6-18GHz and azimuth scan coverage of 60 degrees is also presented. The active reflection coefficient of the array is calculated from measured mutual coupling coefficients and the array pattern over different scan angles is demonstrated. The grating lobe free scan coverage of 60 degrees is obtained. The antenna array finds application in airborne systems.

An 85-year-old man was referred for an MRI scan of the pelvis for further evaluation of a suspected left neck of femur fracture, which was regarded as equivocal on plain radiograph and CT. The initial MRI demonstrated unusual appearances of the visualised bone marrow and subcutaneous adipose tissue and was initially misinterpreted as a technical malfunction of the scanner. However, a repeat study on a different scanner the following day once again demonstrated the same appearances. The appearances were consistent with serous atrophy of bone marrow, a non-neoplastic disorder of the bone marrow, which is most commonly seen in severe anorexia nervosa or cachexia. These unusual, but distinct, bone marrow and subcutaneous adipose tissue appearances, which are specific to MRI, have been colloquially termed as the ‘flip-flop’ effect.

Aim The aim of the study was to evaluate whether the twinkle artefact is a valuable feature in the sonographic diagnosis of superficial epidermoid cysts. Materials and methods A retrospective search was undertaken of our institution’s Radiology Information System and pathology database to identify cases of superficial masses showing the twinkle artefact that proceeded to surgical excision. Results Eighteen superficial masses demonstrating the twinkle artefact were identified that were submitted for pathological analysis. Of these, 17 were confirmed to represent epidermoid cysts and only 1 case had an alternative diagnosis (proliferating trichilemmal cyst). Conclusion The presence of the twinkle artefact appears to be a specific and valuable ancillary sonographic feature for the diagnosis of superficial epidermoid cysts.

This paper proposes a multi-band SIW antenna which is linearly polarized. The antenna consists of a T-shaped radiator inscribed on the upper side of the dielectric substrate. This radiator is responsible for multi-band occurrence. The operating frequency is chosen to be 28 GHz, which is a valid selection for 5G applications. An aperiodic modulated metasurface is employed as the ground plane for the proposed antenna. Modulated MTS is a great alternative to the metal ground as it enhances the gain and subsequently the front to back lobe ratio (FTBR) of the antenna. The substrate used is FR4 epoxy with a thickness of 0.8 mm. The simulations are done using ANSYS HFSS. Only simulated results are presented as the antenna fabrication is under process.

In this paper, the design of a linearly polarized substrate integrated waveguide (SIW) antenna operating at a frequency of 54 GHz is proposed. Gain achieved is approxiamtely 7.8 dBi. A comparative study based on the introduction of slots in the basic SIW cavity design and how it affects the resonant frequency and impedance bandwidth is done. $TE_{104}$ is the mode under consideration. The substrate used is RT/Duroid 3003. The simulation is carried out in ANSYS HFSS and only simulated results are presented. The fabrication of the antenna is under process.

Introduction Simulation is increasingly used throughout medicine. Within ultrasound, simulators are more established for learning transvaginal and interventional procedures. The use of modern high-fidelity transabdominal simulators is increasing, particularly in centres with large trainee numbers. There is no current literature on the value of these simulators in gaining competence in abdominal ultrasound. The aim was to investigate the impact of a new ultrasound curriculum, incorporating transabdominal simulators into the first year of training in a UK radiology academy. Methods The simulator group included 13 trainees. The preceding cohort of 15 trainees was the control group. After 10 months, a clinical assessment was performed to assess whether the new curriculum resulted in improved ultrasound skills. Questionnaires were designed to explore the acceptability of simulation training and whether it had any impact on confidence levels. Results Trainees who had received simulator-enriched training scored higher in an objective clinical ultrasound assessment, which was statistically significant ( p = 0.0463). End confidence scores for obtaining diagnostic images and demonstrating pathology were also higher in the simulation group. All trainees stated that transabdominal simulator training was useful in early training. Conclusions This initial study shows that embedded into a curriculum, transabdominal ultrasound simulators are an acceptable training method that can result in improved ultrasound skills and higher confidence levels. Using simulators early in training could allow trainees to master the basics, improve their confidence, enabling them to get more educational value from clinical ultrasound experience while reducing the impact of training on service provision.

Sonography is widely used for evaluation of hand and wrist lesions. The easy accessibility, cost-effectiveness, and good diagnostic accuracy of sonography coupled with the numerous benefits of real-time imaging make it desirable. The aim of this article is to describe the typical sonographic appearances of lesions in the hand and wrist that are encountered frequently in routine clinical practice, such as inflammatory arthropathies, tumors, traumatic injuries, foreign bodies, and nerve entrapment syndromes. Relevant anatomy, scanning methods, and recent developments in musculoskeletal sonography are also discussed.

Vertebral compression fractures are common in elderly populations and in particular in postmenopausal women as a consequence of osteoporosis. Percutaneous vertebroplasty and kyphoplasty are minimally invasive procedures that are increasingly used to treat persistent or severe acute pain from these fractures. Vertebroplasty works by augmenting the weak osteopenic vertebrae with polymethylmethacrylate (PMMA) bone cement and thus preventing further microfractures and associated pain. The aim of kyphoplasty is pain relief combined with restoration of vertebral body height and reduction in kyphosis. This is achieved by 'expanding' the fractured vertebra with a balloon and then filling of the resultant cavity with PMMA cement. Vertebroplasty and kyphoplasty are undertaken under local and general anaesthesia, respectively. Both procedures have a very low complication rate if properly performed by well trained clinicians using appropriate cement and technique and highquality imaging. Patient selection and the selection of the level at which the percutaneous vertebroplasty is to be done are of utmost importance for maximal therapeutic benefit. Additional trials are required to establish conclusively the effectiveness of both procedures compared with conservative medical therapy and each other.

A 24 year old man presented with a three year history of right groin pain, which was initially managed with physiotherapy for muscle strain. Pelvic radiography showed ill defined …

Little is known regarding the exact pathogenesis of sarcoidosis, but it is widely recognized that it affects multiple organs. The presentation and imaging features can be nonspecific, and this is the reason why it is a great mimic of other diseases. Diagnosis of sarcoidosis is often prompted initially by clinical suspicion. Imaging plays a crucial role in both detection and monitoring of disease process. This review is a case-based systemic approach looking at various systemic manifestation of the disease presenting real clinical encounters using various imaging modalities.

The use of computed tomography (CT) in imaging has expanded radically in the last four decades since its invention. Aided by advances in computing and engineering, it has grown from being an object of curiosity in research institutions to the main modality of medical imaging across the world. Although at present, the most common use of computed tomography with respect to imaging of the hand and wrist is in trauma; easy availability, high spatial resolution and recent innovations are helping it to break new ground in assessment of soft tissue structures and dynamic imaging.

Increasing use of a wide variety of therapeutic drugs with known musculoskeletal side-effect profiles necessitates a rigorous understanding and approach when evaluating imaging features suggestive of drug-induced musculoskeletal abnormalities. The etiology of such abnormalities is diverse, and the clinical and imaging manifestations may be nonspecific. The recognition of adverse effects depends, first, on the physician's vigilant review of clinical information for relevant drug history and indicative signs, and second, on the radiologist's ability to detect musculoskeletal changes consistent with known potential effects of specific drugs. Musculoskeletal abnormalities induced by therapeutic drugs may be broadly categorized as embryopathic, juvenile, or postmaturation. Embryopathic skeletal abnormalities result from the teratogenic effects of drugs administered to pregnant women (eg, thalidomide, anticonvulsants). Other therapeutic agents characteristically lead to abnormalities during postnatal skeletal maturation (eg, high-dose vitamins or prostaglandin) either because they are used exclusively in children or because they have idiosyncratic effects on immature musculoskeletal structures. Many drugs (eg, statins) may have musculoskeletal side effects that, although independent of the stage of skeletal maturation, are most often seen in adults or elderly people because they are commonly prescribed for people in these age groups. Drug-induced musculoskeletal abnormalities may be further characterized according to the predominant skeletal manifestations as osteomalacic, proliferative, or osteoporotic and according to the involvement of soft tissues as musculotendinous or chondral.

Although, the diagnosis and evaluation of sarcoidosis has traditionally remained confined to the chest, its multi-system nature has been widely recognized. Radiological features of pulmonary sarcoidosis are well known but extra-pulmonary manifestations can produce a plethora of non-specific imaging findings that can affect subcutaneous tissue, and the neurological, cardiac, gastrointestinal, urological, liver, spleen, and skeletal systems. In the literature, there are various case reports and specific system reviews but there are few reviews that encompass all the extra-pulmonary manifestations. In this paper, we comprehensively review the imaging features of extra-pulmonary sarcoidosis with characteristic features as well as atypical presentations. In addition, we discuss the emerging role of nuclear medicine in sarcoidosis.

AJR 2010; 195:S29–S31 0361–803X/10/1953–S29 © American Roentgen Ray Society Clinical History A 40-year-old man presented with a history of coccydynia of 8 months’ duration. The pain started after he fell on the coccyx while playing squash. He also complained of occasional tenesmus. No neurologic symptoms were noted. Clinical examination revealed only tenderness over the coccyx. Radiography, followed by CT of the thorax, abdomen, and pelvis, and MRI of the pelvis were performed. Ultrasound-guided biopsy of the mass was performed to confirm the diagnosis.

Sub-trochanteric femoral fractures as a complication of long standing bisphosphonate therapy are rare. Drug regulatory authorities like MHRA in the UK (Medicines and Healthcare products Regulatory Agency) have recently alerted specialists about this complication. We describe and illustrate the plain radiographic, CT and MRI features and emphasize the role of imaging in the accurate diagnosis of this new type of insufficiency fractures. There is paucity of radiology literature on this topic and hence awareness of the typical imaging features helps to prevent misdiagnosis and delayed treatment. Our patients were on bisphosphonates (alendronate) for more than 3 years duration and presented with anterolateral thigh pain to the emergency department.

The aim of this thesis was to implement prototype which, provides relevant information to the user at right time. The personal information that is targeted here was health-related information. This may include various type of information, such as drug information, education information, health monitor data for instance glucoses meter, step counter, personal notes, health related images ,PDF files. To implement prototype, we use metadata of the information. Some of the metadata of the information describes the context of the information. We used time, date and location context of information to implement our goal successfully. By using these contexts of the information, the relevant information to user is provided. The four components were implemented to implement prototype: Metadata extractor, Information manger, controller and user interface. The metadata extractor allows user to download files and automatically store file in to the download folder and context of these files was extracted and stored in to the database. The second component was information manger; the main function of this component was to reads the context of downloaded files and make association of similar files by using context. The third component was controller, it was use to represent related files to the end users and the user interface allows user to interact with our system. The implemented prototype was tested for providing related information to the users. The information access was based on the context of the information, which eases to get results and to recognize useful information for the users. It was also tested whether the prototype stores updated files or not. The prototype makes association of new downloaded files to the database and it also avoids redundancy of files. Thus, it helps users to access the updated information and to reduce redundancy of data. The prototype provides user with the right set of information to the right time, by identifying the need of the users by matching with available information.

AJR 2009;193:S56–S58 0361–803X/09/1933–S56 © American Roentgen Ray Society Clinical History A 77-year-old man presented with neurogenic claudication of the lower limbs that had gradually progressed over the past 8 months. The pain was worse on the left side. Relevant medical history included lumbar spinal canal stenosis treated by left L4 laminectomy 5 years earlier. There was no associated sensory disturbance. MRI of the lumbar spine was performed.