Delivery of hepatocyte growth factor mRNA from nanofibrillar scaffolds in a pig model of peripheral arterial disease

Background: Chemical modification of mRNA (mmRNA) substantially improves their stability and translational efficiency within cells. Nanofibrillar collagen scaffolds were previously shown to enable the spatially localized delivery and temporally controlled release of mmRNA encoding HGF both in vitro and in vivo. Materials & methods: Herein we developed an improved slow-releasing HGF mmRNA scaffold and tested its therapeutic efficacy in a porcine model of peripheral arterial disease. Results & conclusion: The HGF mmRNA was released from scaffolds in a temporally controlled fashion in vitro with preserved transfection activity. The mmRNA scaffolds improved vascular regeneration when sutured to the ligated porcine femoral artery. These studies validate the therapeutic potential of HGF mmRNA delivery from nanofibrillar scaffolds for treatment of peripheral arterial disease.

Regulatory T cell transfer ameliorates lymphedema and promotes lymphatic vessel function

Secondary lymphedema is a common postcancer treatment complication, but the underlying pathological processes are poorly understood and no curative treatment exists. To investigate lymphedema pathomechanisms, a top-down approach was applied, using genomic data and validating the role of a single target. RNA sequencing of lymphedematous mouse skin indicated upregulation of many T cell-related networks, and indeed depletion of CD4⁺ cells attenuated lymphedema. The significant upregulation of Foxp3, a transcription factor specifically expressed by regulatory T cells (Tregs), along with other Treg-related genes, implied a potential role of Tregs in lymphedema. Indeed, increased infiltration of Tregs was identified in mouse lymphedematous skin and in human lymphedema specimens. To investigate the role of Tregs during disease progression, loss-of-function and gain-of-function studies were performed. Depletion of Tregs in transgenic mice with Tregs expressing the primate diphtheria toxin receptor and green fluorescent protein (Foxp3-DTR-GFP) mice led to exacerbated edema, concomitant with increased infiltration of immune cells and a mixed T_H1/T_H2 cytokine profile. Conversely, expansion of Tregs using IL-2/anti-IL-2 mAb complexes significantly reduced lymphedema development. Therapeutic application of adoptively transferred Tregs upon lymphedema establishment reversed all of the major hallmarks of lymphedema, including edema, inflammation, and fibrosis, and also promoted lymphatic drainage function. Collectively, our results reveal that Treg application constitutes a potential new curative treatment modality for lymphedema.

Electric fly swatter: potentially harmful not only for insects?

The electric fly-swatter is a household device used widely in Greece to kill mosquitoes. It consists of a racket-shaped electrical screen which is free of toxic and other chemicals. When the screen touches the insects, the contact generates an electric flash of light and the insects are incinerated. We present the case of a 15% flame burn caused by the flash of light produced by an electric fly-swatter. According to our review of the literature, this is the second case of burn injury caused by an electric fly swatter.

A 35-year-old woman presenting with an unusual post-traumatic leiomyoma of the nipple: a case report

Introduction

Leiomyoma of the mammary papilla is one of the most uncommon nipple tumors with only 50 cases reported in the literature until now. To the best of our knowledge we present the first report of a nipple leiomyoma that originated from a traumatic abrasion caused by breastfeeding.

Case presentation

A 35-year-old healthy Caucasian female with a cauliflower-like tender and pink nodular mass that was approximately 10mm in diameter presented to our out-patients department. The patient suggested that the mass originated from a traumatic abrasion caused by breastfeeding three years ago and it has been slowly growing ever since.

An excision biopsy was performed. The histological and immunohistochemical examination confirmed the diagnosis of leiomyoma. There were no postoperative complications or any sign of local recurrence four years postoperatively.

Conclusions

Leiomyoma of the mammary papilla is a rare benign neoplasm that usually appears as a solid tender nodule. Differential diagnosis comprises breast carcinoma, leiomyosarcoma and myoid hamartoma. The recommended treatment is complete excision of the tumor with histologically confirmed tumor-free margins otherwise recurrence is possible. A detailed history of the patient’s disease can reveal the original etiology. This is an original case report that will have particular interest to plastic surgeons, dermatologists, and pathologists. The pathogenetic mechanism was trauma of the nipple. According to our review of the literature this particular information has never been reported and we think that it may advance our knowledge of this very infrequent tumor.

The wash-out technique in the management of delayed presentations of extravasation injuries

Late presentation of extravasation injuries from chemotherapeutic agents is not uncommon. Twenty-four patients with extravasation injuries presented with upper limb extravasation but without any skin necrosis between the second and the fourteenth day following injury day. We flushed out the infiltrated area with 300-500 ml of normal saline through multiple stab incisions. All 24 patients responded well to the procedure and no further complications occurred. The average time for the complete healing of the wounds was 15 days. All the patients were able to continue their chemotherapy treatment without delay. Patients were followed up for a mean period of 13 months. They all recovered with no functional deficit and only mild scarring. Early recognition and immediate treatment of extravasation injuries are of paramount importance. In cases with no evidence of skin necrosis, a delayed wash-out procedure appears to be very effective in removing the extravasated drug and minimizing further tissue damage.