Clinical application of decellularized and lyophilized human amnion/chorion membrane grafts for closing post‐laryngectomy pharyngocutaneous fistulas

Background and Objectives

Squamous cell carcinoma is the most common pathological type among the cancers of the larynx. Standard treatment for squamous cell carcinoma of the larynx is the combination of chemotherapy, radiotherapy, and laryngectomy. Pharyngocutaneous fistula is a common complication of laryngectomy. We hypothesized that decellularized and lyophilized human amnion/chorion membrane can be an effective, non‐invasive method of treating pharyngocutaneous fistula.

Methods

A total of 67 patients with laryngeal squamous cell carcinoma were retrospectively analyzed after treatment in a prospective trial. After preoperative chemotherapy, radiotherapy, and total or extended laryngectomy, primary wound healing occurred in 42 (62.7%) patients. Pharyngocutaneous fistula developed in 8 (11.9%) patients. Decellularized and lyophilized human amnion/chorion membrane grafts were used to reconstruct the fistulas.

Results

The average time for the full healing of the wound in all patients after transplantation of these grafts was 18 days.

Conclusion

The advantages of using these grafts over other existing methods of pharyngocutaneous fistula treatment are that they are non‐invasive, prevent donor morbidity, and enable management of the wound without using classical wound gauze. J. Surg. Oncol. 2016;113:538–543. © 2016 The Authors. Journal of Surgical Oncology Published by Wiley Periodicals, Inc.     

Prevalence of and factors influencing smoking among medical and non-medical students in Tbilisi,Georgia

OBJECTIVE:

Smoking is a serious problem that has a devastating impact on health. The objective of this study was to describe the prevalence of and factors influencing smoking among medical and non-medical students in Tbilisi, Georgia, as well as to determine whether medical education has an impact on smoking.

METHODS:

A cross-sectional study was carried out at Tbilisi State Medical University and Tbilisi State University, both of which are located in Tbilisi, Georgia. A total of 400 4th-year students (200 students at each university) were asked to complete standardized questionnaires.

RESULTS:

Of the sample as a whole, 48.75% were identified as smokers and 51.25% were identified as nonsmokers. The mean age was 20.24 years among smokers and 20.26 years among nonsmokers. Of the medical students, 49.5% were smokers, as were 48.0% of the non-medical students. The male-to-female ratio in the study population was 0.9:1.1. Smoking was found to have a strong relationship with gender, males accounting for 65% of all smokers. Of the smokers, 56.9% stated that they would like to quit smoking (for health or financial reasons). Of the medical students, 59.5% expressed a willingness to quit smoking, as did 54.2% of the non-medical students.

CONCLUSIONS:

There is a need to improve smoking education for undergraduate students. Special attention should be given to the inclusion of anti-smoking education in undergraduate curricula, as well as to the implementation of smoking prevention campaigns at institutions of higher education. However, such measures will be effective only if tobacco control policies are strictly enforced on the national level as well.     

Distribution and Detection of Radiopaque Beads after Hepatic Transarterial Embolization in Swine: Cone-Beam CT versus MicroCT

Purpose

To determine the true distribution of radiopaque beads (ROBs) after hepatic embolization in swine as imaged by micro-computed tomography (microCT) compared with in vivo cone-beam computerized tomography (CT) imaged at different kVp settings.

Lyso-thermosensitive liposomal doxorubicin for treatment of bladder cancer

Purpose: To evaluate lyso-thermosensitive liposomal doxorubicin (LTLD, ThermoDox^®) in combination with loco-regional mild hyperthermia (HT) for targeted drug delivery to the bladder wall and potential treatment of bladder cancer.

Material and methods: Porcine in vivo studies were performed with the following groups: (i) intravenous (IV) LTLD with hyperthermia (LTLD?+?HT); (ii) IV doxorubicin (DOX) with hyperthermia (IV DOX?+?HT) and (iii) IV LTLD without hyperthermia (LTLD – HT). Drug formulations were delivered via 30?min IV infusion coinciding with 1-h bladder irrigation (45?°C water for HT groups, 37?°C for non-HT group), followed by immediate bladder resection. DOX concentrations were measured in consecutive sections parallel to the bladder lumen by liquid chromatography following drug extraction. Computer models were developed to simulate tissue heating and drug release from LTLD.

Results: Comparing mean DOX concentrations at increasing depths from the lumen to outer surface of the bladder wall, the ranges for LTLD?+?HT, IV DOX?+?HT and LTLD – HT, respectively, were 20.32–3.52?μg/g, 2.34–0.61?μg/g and 2.18–0.51?μg/g. The average DOX concentrations in the urothelium/lamina and muscularis, respectively, were 9.7?±?0.67 and 4.09?±?0.81?μg/g for IV LTLD?+?HT, 1.2?±?0.39 and 0.86?±?0.24?μg/g for IV DOX?+?HT, and 1.15?±?0.38 and 0.62?±?0.15?μg/g for LTLD – HT. Computational model results were similar to measured DOX levels and suggest adequate temperatures were reached within the bladder wall for drug release from LTLD.

Conclusions: Doxorubicin accumulation and distribution within the bladder wall was achieved at concentrations higher than with free IV doxorubicin by mild bladder hyperthermia combined with systemic delivery of LTLD.     

Impact of COVID-19 on global HCV elimination efforts

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Attractive emulsion droplets probe the phase diagram of jammed granular matter

It remains an open question whether statistical mechanics approaches apply to random packings of athermal particles. Although a jamming phase diagram has recently been proposed for hard spheres with varying friction, here we use a frictionless emulsion system in the presence of depletion forces to sample the available phase space of packing configurations. Using confocal microscopy, we access their packing microstructure and test the theoretical assumptions. As a function of attraction, our packing protocol under gravity leads to well-defined jammed structures in which global density initially increases above random close packing and subsequently decreases monotonically. Microscopically, the fluctuations in parameters describing each particle, such as the coordination number, number of neighbors, and local packing fraction, are for all attractions in excellent agreement with a local stochastic model, indicating that long-range correlations are not important. Furthermore, the distributions of local cell volumes can be collapsed onto a universal curve using the predicted k-gamma distribution, in which the shape parameter k is fixed by the polydispersity while the effect of attraction is captured by rescaling the average cell volume. Within the Edwards statistical mechanics framework, this result measures the decrease in compactivity with global density, which represents a direct experimental test of a jamming phase diagram in athermal systems. The success of these theoretical tools in describing yet another class of materials gives support to the much-debated statistical physics of jammed granular matter.     

Enhanced levels of Hsulf-1 interfere with heparin-binding growth factor signaling in pancreatic cancer

   

Hsulf-1 is a newly identified enzyme, which has the ability to decrease the growth of hepatocellular, ovarian, and head and neck squamous cell carcinoma cells by interfering with heparin-binding growth factor signaling. Since pancreatic cancers over-express a number of heparin-binding growth factors and their receptors, the expression and function of this enzyme in pancreatic cancer was analyzed.