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Evolution of superficial spreading melanoma to resemble desmoplastic melanoma: case report.
Desmoplastic melanoma commonly occurs on the head and neck in a pure form, but occasionally, it occurs in a mixed tumor with another type, usually superficial spreading melanoma (SSM), and rarely as a metastasis from a primary SSM. We report here a primary SSM on the leg of a 32-year-old male which metastasised to lymph nodes, and 10Â years later recurred at the primary site initially with mixed features but evolving to resemble a uniformly desmoplastic, deeply invasive melanoma. This unusual case has implications for clinical management and is additionally notable for its reversal in behavior, from metastatic to local infiltrative type, correlating with the change in morphology
Hierarchical structures of cactus spines that aid in the directional movement of dew droplets
Three species of cactus whose spines act as dew harvesters were chosen for this study: Copiapoa cinerea var. haseltoniana, Mammillaria columbiana subsp. yucatanensis and Parodia mammulosa and compared with Ferocactus wislizenii whose spines do not perform as dew harvesters. Time-lapse snapshots of C. cinerea showed movement of dew droplets from spine tips to their base, even against gravity. Spines emanating from one of the areoles of C. cinerea were submerged in water laced with fluorescent nanoparticles and this particular areole with its spines and a small area of stem was removed and imaged. These images clearly showed that fluorescent water had moved into the stem of the plant. Lines of vascular bundles radiating inwards from the surface areoles (from where the spines emanate) to the core of the stem were detected using magnetic resonance imaging, with the exception of F. wislizenii that does not harvest dew on its spines. Spine microstructures were examined using SEM images and surface roughness measurements (Ra and Rz) taken of the spines of C. cinerea. It was found that a roughness gradient created by tapered microgrooves existed that could potentially direct surface water from a spine tip to its base
Mixed material wear particle isolation from periprosthetic tissue surrounding total joint replacements
Submicron-sized wear particles are generally accepted as a potential cause of aseptic loosening when produced in sufficient volumes. With the accelerating use of increasingly wear-resistant biomaterials, identifying such particles and evaluating their biological response is becoming more challenging. Highly sensitive wear particle isolation methods have been developed but these methods cannot isolate the complete spectrum of particle types present in individual tissue samples. Two established techniques were modified to create one novel method to isolate both high- and low-density materials from periprosthetic tissue samples. Ten total hip replacement and eight total knee replacement tissue samples were processed. All particle types were characterized using high resolution scanning electron microscopy. UHMWPE and a range of high-density materials were isolated from all tissue samples, including: polymethylmethacrylate, zirconium dioxide, titanium alloy, cobalt chromium alloy and stainless steel. This feasibility study demonstrates the coexistence of mixed particle types in periprosthetic tissues and provides researchers with high-resolution images of clinically relevant wear particles that could be used as a reference for future in vitro biological response studies
Isolation and characterisation of wear debris surrounding failed total ankle replacements
Aseptic loosening and osteolysis continue to be a short- to mid-term problem for total ankle replacement (TAR) devices. The production of wear particles may contribute to poor performance, but their characteristics are not well understood. This study aimed to determine the chemical composition, size and morphology of wear particles surrounding failed TARs. A recently developed wear particle isolation method capable of isolating both high- and low-density materials was applied to 20 retrieved periprosthetic tissue samples from 15 failed TARs of three different brands. Isolated particles were imaged using ultra-high-resolution imaging and characterised manually to determine their chemical composition, size, and morphology. Six different materials were identified, which included: UHMWPE, calcium phosphate (CaP), cobalt chromium alloy (CoCr), commercially pure titanium, titanium alloy and stainless steel. Eighteen of the 20 samples contained three or more different wear particle material types. In addition to sub-micron UHMWPE particles, which were present in all samples, elongated micron-sized shards of CaP and flakes of CoCr were commonly isolated from tissues surrounding AES TARs. The mixed particles identified in this study demonstrate the existence of a complex periprosthetic environment surrounding TAR devices. The presence of such particles suggests that early failure of devices may be due in part to the multifaceted biological cascade that ensues after particle release. This study could be used to support the validation of clinically-relevant wear simulator testing, pre-clinical assessment of fixation wear and biological response studies to improve the performance of next generation ankle replacement devices
Cis and Trans Effects of Human Genomic Variants on Gene Expression
This work was funded by the Louis-Jeantet Foundation (http://www.jeantet.ch/), the European Research Council (Grant ID: 260927 http://erc.europa.eu/), the Swiss National Foundation (Grant ID: 130342 http://www.snf.ch), NCCR Frontiers In Genetics (http://www.frontiers-in-genetics.org), the UK Medical Research Council (http://www.mrc.ac.uk) and the Wellcome Trust (Grant ID: 092731).
Pyoderma gangrenosum after caesarean section: a case report
BACKGROUND: Pyoderma gangrenosum is a rare ulcerative skin disease. The diagnosis is based on clinical features and excluding other causes of skin ulcers, as it does not have characteristic histopathology or laboratory findings. The etiology is poorly understood. Lesions can develop spontaneously, after surgery or after trauma. CASE PRESENTATION: We present the case of a 32-year-old woman with ulcerative wound defect after caesarean section. The wound was not healing despite standard wound care and antibiotic treatment. Pyoderma gangrenosum was diagnosed and after high dose corticosteroids wound healing started. CONCLUSION: Early diagnosis and subsequent treatment of pyoderma gangrenosum are crucial for limiting scar tissue. Diagnosis of pyoderma gangrenosum could easily be missed since gynaecologists are rarely confronted with this disorder
The α2δ-like Protein Cachd1 Increases N-type Calcium Currents and Cell Surface Expression and Competes with α2δ-1
Voltage-gated calcium channel auxiliary α2δ subunits are important for channel trafficking and function. Here, we compare the effects of α2δ-1 and an α2δ-like protein called Cachd1 on neuronal N-type (CaV2.2) channels, which are important in neurotransmission. Previous structural studies show the α2δ-1 VWA domain interacting with the first loop in CaV1.1 domain-I via its metal ion-dependent adhesion site (MIDAS) motif and additional Cache domain interactions. Cachd1 has a disrupted MIDAS motif. However, Cachd1 increases CaV2.2 currents substantially (although less than α2δ-1) and increases CaV2.2 cell surface expression by reducing endocytosis. Although the effects of α2δ-1 are abolished by mutation of Asp122 in CaV2.2 domain-I, which mediates interaction with its VWA domain, the Cachd1 responses are unaffected. Furthermore, Cachd1 co-immunoprecipitates with CaV2.2 and inhibits co-immunoprecipitation of α2δ-1 by CaV2.2. Cachd1 also competes with α2δ-1 for effects on trafficking. Thus, Cachd1 influences both CaV2.2 trafficking and function and can inhibit responses to α2δ-1
Systematic review of communication technologies to promote access and engagement of young people with diabetes into healthcare
Background: Research has investigated whether communication technologies (e.g. mobile telephony, forums,
email) can be used to transfer digital information between healthcare professionals and young people who live
with diabetes. The systematic review evaluates the effectiveness and impact of these technologies on
communication.
Methods: Nine electronic databases were searched. Technologies were described and a narrative synthesis of all
studies was undertaken.
Results: Of 20,925 publications identified, 19 met the inclusion criteria, with 18 technologies assessed. Five
categories of communication technologies were identified: video-and tele-conferencing (n = 2); mobile telephony
(n = 3); telephone support (n = 3); novel electronic communication devices for transferring clinical information (n =
10); and web-based discussion boards (n = 1). Ten studies showed a positive improvement in HbA1c following the
intervention with four studies reporting detrimental increases in HbA1c levels. In fifteen studies communication
technologies increased the frequency of contact between patient and healthcare professional. Findings were
inconsistent of an association between improvements in HbA1c and increased contact. Limited evidence was
available concerning behavioural and care coordination outcomes, although improvement in quality of life, patientcaregiver
interaction, self-care and metabolic transmission were reported for some communication technologies.
Conclusions: The breadth of study design and types of technologies reported make the magnitude of benefit and
their effects on health difficult to determine. While communication technologies may increase the frequency of
contact between patient and health care professional, it remains unclear whether this results in improved
outcomes and is often the basis of the intervention itself. Further research is needed to explore the effectiveness
and cost effectiveness of increasing the use of communication technologies between young people and
healthcare professionals
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