Cutaneous Crohn disease presenting as "knife-edged" ulcers: a case report.

BACKGROUND: CCD presents as non-caseating granulomas within the skin at a site distant from the GI tract. CCD is a debilitating extraintestinal sequela of CD that can sometimes precede its GI manifestations. In the absence of GI symptoms, the histopathologic and clinical features of CCD can present as a variety of inflammatory skin conditions that can range from ruptured follicle-associated granulomas to cutaneous ulcerations. While a variety of therapeutic options for patients with CCD and concurrent luminal CD have been described in the literature, there is no standard treatment algorithm for the management of refractory CCD with limited or covert GI involvement. CASE REPORT: The authors discuss the case of a 33-year-old female who presented to the wound care clinic with multiple "knife-edged" cutaneous ulcerations involving the intertriginous spaces, found to be consistent with CCD. Her original cutaneous symptoms and diagnosis manifested with minimal GI involvement and responded to IVIG treatment. CONCLUSIONS: This case supports the inclusion of CCD in the differential diagnosis in patients with knife-edged granulomatous skin lesions in intertriginous locations. This clinical condition may present in the setting of no or limited GI symptoms. The management of CCD and a proposed treatment algorithm are also presented.

DRUG-ELUTING STENTS IN THE TREATMENT OF PATIENTS WITH OCCLUSIVE-STENOTIC LESIONS OF THE SUPERFICIAL FEMORAL ARTER.

OBJECTIVE: The aim: To analyze the results of endovascular revascularization of the femoropopliteal segment using drug-eluting stents. PATIENTS AND METHODS: Materials and methods: Endovascular intervention was performed in 23 patients with occlusive-stenotic lesions of the superficial femoral artery (SFA). Paclitaxel-eluting stents were used. There were 16 (69.6%) patients with diabetes mellitus type 2 and diabetic angiopathy, and 7 (30.4%) patients had obliterating atherosclerosis of the arteries of the lower limbs. Critical ischemia of the lower extremities was diagnosed in 18 (78.3%) cases, and intermittent claudication - in 5 (21.7%). RESULTS: Results: Twenty (86.6 %) scheduled procedures for stenting of the SFA were technically successful. During follow-up period (3 months), there were no cases of reocclusion or clinically significant restenosis at the stented level. There were no "major" amputations during follow -up period. "Small" ankle amputations were performed in 7 (35%) patients with diabetic gangrene. CONCLUSION: Conclusions: Implantation of drug-eluting stents is an effective method of endovascular revascularization in patients with SFA lesions. To compare the results of implantation of drug-eluting stents with other methods of revascularization of the lesions of the femoro-popliteal segment, it is necessary to accumulate more data and increase the duration of the follow-up period.

Compression therapy in peripheral artery disease: a literature review.

OBJECTIVE: Our objective is to examine the pathophysiology of oedema in the ischaemic and post-revascularised limb, compare compression stockings to pneumatic compression devices, and summarise compression regimens in patients with severe peripheral artery disease (PAD) without revascularisation, after revascularisation, and in mixed arterial and venous disease. METHOD: A scoping literature review of the aforementioned topics was carried out using PubMed. RESULTS: Compression therapy has been shown to increase blood flow and aid in wound healing through a variety of mechanisms. Several studies suggest that intermittent pneumatic compression (IPC) devices can be used to treat critical limb ischaemia in patients without surgical options. Additionally, compression stockings may have a role in preventing oedema after peripheral artery bypass surgery, thereby diminishing pain and reducing the risk of surgical wound dehiscence. CONCLUSION: Oedema may occur in the ischaemic limb after revascularisation surgery, as well as in combination with venous disease. Clinicians should not fear using compression therapy in PAD.

Atypical ulcers: a stepwise approach for clinicians.

Chronic ulcers are associated with significant morbidity and mortality. Typical ulcers are due to venous insufficiency, diabetes, ischemia, pressure, and lymphedema. A chronic ulcer that does not respond to standard therapies should be reevaluated for potential atypical etiologies. Atypical ulcers are less common and more difficult to diagnose due to a wide range of possible etiologies, including inflammatory (autoimmune), neoplastic, vasculopathy, hematologic, infectious, drug-induced, or external. No standardized approach to the management of complex atypical ulcers exists. In this review, a stepwise approach to atypical ulcers is proposed with the aim of assisting physicians in their identification and diagnosis. If perfusion is adequate and there are no signs of infection, then the authors recommend obtaining an ulcer biopsy for microbiologic, DIF, and histopathologic evaluation as the criterion standard for diagnosis. Laboratory testing, including an autoimmune panel, a hypercoagulable panel, and an infectious diseases panel, can further aid in diagnosis. Atypical ulcers often require multidisciplinary care, with input from specialists in rheumatology, dermatology, infectious diseases, wound care, vascular surgery, hematology, and oncology. Effective communication within the health care team is essential for accurate diagnosis and management of atypical ulcers. Active dialogue between providers can improve consult efficiency and ultimately lower the cost of care.

Fundamental insight into critical phenomena in condensation growth of nanoparticles in a flame.

The paper deals with the gas-phase formation of nanoparticles that is a fundamental process responsible for the condensed matter in the Universe, which also attracts attention due to its involvement in the particle synthesis for various nanotechnology applications. Previously reported results on MgO nano-oxides formed by Mg combustion showed a unique phenomenon coined "the condensation stagnation" that is the occurrence of critical clusters with suppressed growth. Here we focus on the effect of an external ionizer on this condensation growth stagnation. We show that the condensation stagnation occurring in the Mg particle flame subjected to a positive ion flux is similar to that in the unaffected flame. In contrast, applying negative charging significantly influences the state of stagnation of the system, i.e., no critical clusters are observed in the products sampled from the flame. The discovered critical behavior of the state of stagnation is explained in terms of the heat transfer between the condensed MgO nanoparticles and the surrounding gas, which efficiency depends on the sign of the nanoparticle charge. This dependence of the heat transfer efficiency on the nanoparticle charge is a new fundamental effect that should become the basis for accurate modeling in two-phase high-temperature systems.

Nanoparticle Generation in Glowing Wire Generator: Insight into Nucleation Peculiarities.

The paper studies nanoparticle formation in a glowing wire generator (GWG), in which the gas carrier flows around heated metal wire, producing aerosols from a vapor released from the surface. The device has been customized, enabling the use of a double-wire in different orientations in regard to the gas flow. Such alterations provided different effective distances between wires enabling investigation of their mutual influence. Concentration of particles produced in the GWG at different parameters (applied voltage and a gas flow) was carefully measured and analysed. Different regimes of a nanoparticle nucleation were identified that resulted from the applied voltage variation and the gas flow direction. In particular, independent nucleation of nanoparticles on both parts of the wire occurred in the wire plane's configuration perpendicular to the gas flow, whilst dependent nucleation of nanoparticles was observed at a certain specific set of parameters in the configuration, in which the wire plane was parallel to the gas flow. Two corresponding functions were introduced in order to quantify those nucleation regimes and they tend to zero when either independent or dependent nucleation occur. The peculiarities found ought to be considered when designing the multi-wire GWGs in order to further extend the device's range for industrial applications.

Effect of External Charging on Nanoparticle Formation in a Flame.

This paper attempts to demonstrate the importance of the nanoparticle charge in the synthesis flame, for the mechanism of their evolution during formation processes. An investigation was made of MgO nanoparticles formed during combustion of magnesium particles. The cubic shape of nanoparticles in an unaffected flame allows for direct interpretation of results on the external flame charging, using a continuous unipolar emission of ions. It was found that the emission of negative ions applied to the flame strongly affects the nanoparticle shape, while the positive ions do not lead to any noticeable change. The demonstrated effect emphasizes the need to take into account all of the phenomena responsible for the particle charge when modeling the nanoparticle formation in flames.

Effect of Laser Irradiation on Emissivity of Flame-Generated Nanooxides.

The application of pyrometry to retrieve particle temperature in particulate-generating flames strictly requires the knowledge of the spectral behavior of emissivity of light-emitting particles. Normally, this spectral behavior is considered time-independent. The current paper challenges this assumption and explains why the emissivity of oxide nanoparticles formed in flame can change with time. The suggested phenomenon is related to transitions of electrons between the valence and conduction energy bands in oxides that are wide-gap dielectrics. The emissivity change is particularly crucial for the interpretation of fast processes occurring during laser-induced experiments. In the present work, we compare the response of titania particles produced by a flame spray to the laser irradiation at two different excitation wavelengths. The difference in the temporal behavior of the corresponding light emission intensities is attributed to the different mechanisms of electron excitation during the laser pulse. Interband transitions that are possible only in the case of the laser photon energy exceeding the titania energy gap led to the increase of the electron density in the conduction band. Relaxation of those electrons back to the valence band is the origin of the observed emissivity drop after the UV laser irradiation.

A Helpful Clue to Calciphylaxis: Subcutaneous Pseudoxanthoma Elasticum-like Changes.

Calciphylaxis, otherwise known as calcific uremic arteriolopathy, is an aggressive disease characterized by painful, ischemic skin lesions with histologic findings of microvascular calcification involving the fat. It is most commonly seen in patients with end-stage renal disease who are on dialysis. Early diagnosis is pivotal for optimal management. However, calciphylaxis can be challenging to diagnose, as many diseases can bear a clinical resemblance to calciphylaxis. Skin biopsies are often necessitated for diagnosis, but unfortunately, one is commonly challenged with a suboptimal amount of subcutaneous fat that does not always show the classic findings of microvascular calcification. However, when calciphylaxis is clinically suspected, the microscopic detection of subcutaneous pseudoxanthoma elasticum (PXE)-like changes, although not unequivocally diagnostic of calciphylaxis, can be a helpful clue in the diagnosis. We report a case of a 49-year-old woman who was diagnosed with uremic calciphylaxis on the basis of the clinical scenario, laboratory testing, and microscopic presence of subcutaneous PXE-like changes that was highlighted with the elastic and von Kossa stains. This case demonstrates the importance of recognizing subcutaneous PXE-like changes on suboptimal skin biopsies that lack microvascular calcification, especially in those patients who are clinically suspect for calciphylaxis as to prevent delay in diagnosis and treatment.

Burn Time of Metal Nanoparticles.

This article will discuss the combustion of metal nanoparticles and explain the burn time dependence on particle size. In contrary to common belief in the power law (tb~d0.3), which, in our knowledge, is simply an experimental fit to data, we propose the logarithmic law (tb~ln(d)) that describes well the known results on nano-aluminum combustion. We derived the logarithmic dependence from a simple model taking into account the energy balance on the surface of a burning metal nanoparticle. The model in question is based on the small energy accommodation coefficient (EAC), which was recently utilized to solve experimental puzzles such as the significant temperature gap between the burning nanoparticle and the environment. A discussion on EAC, which value is important for the correct modeling of nanoparticle combustion, is also included. A way to generalize the considered combustion model is suggested.

A treatment algorithm to identify therapeutic approaches for leg ulcers in patients with sickle cell disease.

Sickle cell leg ulcers (SCLUs) are a common complication of sickle cell disease (SCD). Patients who develop ulcers appear to have a more severe haemolysis-associated vasculopathy than individuals who do not develop them, and manifest other complications such as priapism and pulmonary hypertension. SCLUs are slow to heal and often recur, affecting both the emotional and physical well-being of patients. Here we summarise what is known about the pathophysiology of SCLUs, describe available treatment options and propose a treatment algorithm.

Amniotic membrane is a potential regenerative option for chronic non-healing wounds: a report of five cases receiving dehydrated human amnion/chorion membrane allograft.

A case series of five patients with a total of six chronic non-healing wounds (>30 day duration) were non-randomly selected to evaluate the performance, safety and handling properties of dehydrated human amnion/chorion membrane allograft, an amniotic membrane scaffolding product. The patients had lower extremity wounds that had previously failed standard of care within a university outpatient/inpatient wound healing programme. Five wounds treated with dehydrated amnion/chorion membrane allograft showed a mean 43% area reduction from baseline (51% median) at 3 weeks into treatment and completely healed with a 64-day median time to closure (SD ±27·6 days). One wound worsened at 3 weeks and was found to have a complete central vein obstruction that was treated with long-term mild compression but still eventually healed at 6 months. Removing this outlier, the four responding wounds had a 72% mean and 69% median change in area from baseline, at the 3 week point. All five patients received only one application of dehydrated human amnion/chorion membrane allograft, and there were no adverse events. The product was easy to use, administer and handle. In summary, dehydrated human amnion/chorion membrane allograft appears to be a safe, effective and easy to use therapy for chronic non-healing wounds. This study describes the details of these clinical cases and provides an overview of the current evidence on the use of amniotic tissue in clinical practice.

Calcinosis cutis presenting in the context of long-term therapy for chronic myeloid leukemia: a case report and review of the literature.

Calcinosis cutis is a poorly understood process in which calcium salts deposit in the skin and subcutaneous tissues. Due to its multifactorial pathogenesis, several subtypes and potential etiologies have been described. Presented here is a case of bilateral pretibial calcinosis cutis in a patient on long-term tyrosine kinase inhibitor therapy for chronic myeloid leukemia. The patient initially presented with a right tibial ulceration treated with multiple surgical debridements, antibiotics, and negative pressure wound therapy. The wound was ultimately closed with a split-thickness skin graft. Relevant literature is examined and several possible mechanisms are discussed.

Nanoparticle generation: the concept of a stagnation size region for condensation growth.

We demonstrate that the critical size cluster concept, commonly used in a nucleation theory, should be given some further attention. It has been implied that the supercritical cluster (size larger than critical) can grow via condensation. However, as we show, there is a size range, where the arrival of a vapor molecule onto a cluster surface leads to such a heating of the supercritical cluster that, due to possible evaporation, makes it unstable and, therefore, disables its condensation growth. The described phenomenon leads to substantial accumulation of certain size clusters in the system, which is clearly evident from our experimental investigation. The found suppression of the nucleus growth within the certain size range (exceeding critical) has fundamental implications for many systems where the generation of nanoparticles occur at high temperatures.