Tethering QK peptide to enhance angiogenesis in elastin-like recombinamer (ELR) hydrogels

The development of new capillary networks in engineered constructs is essential for their survival and their integration with the host tissue. It has recently been demonstrated that ELR-based hydrogels encoding different bioactivities are able to modulate their interaction with the host after injection or implantation, as indicated by an increase in cell adhesion and the ability to trigger vascularization processes. Accordingly, the aim of this study was to increase their angiogenic ability both in vitro and in vivo using a small VEGF mimetic peptide named QK, which was tethered chemically to ELR-based hydrogels containing cell-adhesion sequences in their backbone, such as REDV and RGD, as well as a proteolytic site (VGVAPG). In vitro studies were performed using a co-culture of endothelial and fibroblast cells encapsulated into the ELR-based hydrogels in order to determine cell proliferation after 21 days of culture, as well as the number of cell-cell interactions. It was found that although the presence of this peptide does not influence the morphological and rheological properties of these hydrogels, it has an effect on cell behaviour, inducing an increase in cell proliferation and the formation of endothelial cell clusters. In vivo studies demonstrate that the QK peptide enhances the formation of prominent functional capillaries at three weeks post-injection, as confirmed by H&E staining and CD31 immunohistochemistry. The newly formed functional microvasculature ensures perfusion and connection with surrounding tissues. These results show that ELR-QK hydrogels increase capillary network formation and are therefore attractive candidates for application in tissue regeneration, for example for the treatment of cardiovascular diseases such as myocardial infarction or ischemia.

Correction to: SEOM clinical guidelines for anaplastic gliomas (2017)

The SEOM/GEINO clinical guidelines provide recommendations for radiological, and molecular diagnosis, treatment and follow-up of adult patients with anaplastic gliomas (AG). We followed the 2016 WHO classification which specifies the major diagnostic/prognostic and predictive value of IDH1/IDH2 missense mutations and 1p/19q codeletions in AG. The diagnosis of anaplastic oligoastrocytoma is discouraged. Surgery, radiotherapy and chemotherapy with PCV or TMZ are the first-line standard of care for AG with slight modifications according to molecular variables. A multidisciplinary team is highly recommended in the management of these tumors.

Phase II Trial of Oral Tegafur and Folinic Acid with Mitoxantrone as First-Line Regimen in Patients with Metastatic Breast Cancer

Background

Tegafur acts as a deport form of 5-fluorouracil when administered orally for longs periods of time, since it is an active drug in metastatic breast cancer, with response rates of 29-44%. Biochemical modulation with folinic acid and the addition of mitoxantrone could increase the efficacy of tegafur in patients with metastatic breast cancer.

Methods

A prospective phase II trial in patients with previously untreated metastatic breast cancer was carried out. The scheme consisted of mitoxantrone, 12 mg/m2 intravenous day 1, oral tegafur, 750 mg/m2/day divided in three equal doses, and leucovorin 15 mg/8 h orally for days 1-21, given in a 4-week schedule. None patient had received chemotherapy for metastatic breast cancer, although 16 patients had received previous adjuvant chemotherapy.

Results

Thirty-four patients were included. Objective responses were achieved in 20 of 32 patients assessable for response, with 1 complete response and 19 partial responses. The objective response rate was 62.5% (95% confidence intervals, 48-76%). The median duration of response was 10 months. Grade III-IV toxicity according to WHO criteria was digestive (nausea/vomiting) in 12.5%, diarrhea in 25% and stomatitis in 25% of patients. Other toxicities were low. Eight patients required dose-reduction.

Conclusions

We achieved a significant response rate with the scheme, which was administered on an outpatient basis. It seems to be safe and effective as first-line treatment in metastatic breast cancer, with a short median response duration. The size of the trial does not permit definitive conclusions, and the role of biochemical modulation of tegafur in combination with mitoxantrone remains to be defined.

Bioactive scaffolds based on elastin-like materials for wound healing

Wound healing is a complex process that, in healthy tissues, starts immediately after the injury. Even though it is a natural well-orchestrated process, large trauma wounds, or injuries caused by acids or other chemicals, usually produce a non-elastic deformed tissue that not only have biological reduced properties but a clear aesthetic effect. One of the main drawbacks of the scaffolds used for wound dressing is the lack of elasticity, driving to non-elastic and contracted tissues. In the last decades, elastin based materials have gained in importance as biomaterials for tissue engineering applications due to their good cyto- and bio-compatibility, their ease handling and design, production and modification. Synthetic elastin or elastin like-peptides (ELPs) are the two main families of biomaterials that try to mimic the outstanding properties of natural elastin, elasticity amongst others; although there are no in vivo studies that clearly support that these two families of elastin based materials improve the elasticity of the artificial scaffolds and of the regenerated skin. Within the next pages a review of the different forms (coacervates, fibres, hydrogels and biofunctionalized surfaces) in which these two families of biomaterials can be processed to be applied in the wound healing field have been done. Here, we explore the mechanical and biological properties of these scaffolds as well as the different in vivo approaches in which these scaffolds have been used.

Plasminogen Activator Inhibitor-1 Activity and 4G/5G Polymorphism in Hemodialysis

Introduction

Chronic insufficiency alters homeostasis, in part due to endothelial inflammation. Plasminogen activator inhibitor-1 (PAI-1) is increased in renal disease, contributing to vascular damage. We assessed PAI-1 activity and PAI-1 4G/5G polymorphism in hemodialysis (HD) subjects and any association between thrombotic vascular access (VA) events and PAI-1 polymorphism.

Methods

Prospective, observational study in 36 HD patients: mean age: 66.6 ± 12.5 yr, males n=26 (72%), time on HD: 28.71 ± 22.45 months. Vascular accesses: 10 polytetrafluoroethylene grafts (PTFEG), 22 arteriovenous fistulae (AVF), four dual lumen catheters (CAT). Control group (CG): 40 subjects; mean age: 60.0 ± 15 yrs, males n=30 (75%). Group A (GA): thrombotic events (n=12), and group B (GB): No events (n=24). Groups were no different according to age (69.2 ± 9.12 vs. 65.3 ± 14.5 yrs), gender (males: 7; 58.3% vs. 18; 81.8%), time on HD (26.1 ± 14.7 vs. 30.1 ± 38.7 months), causes of renal failure. Time to follow-up for access thrombosis: 12 months.

Results

PAI-1 levels in HD: 7.21 ± 2.13 vs. CG: 0.42 ± 0.27 U/ml (p<0.0001). PAI-1 4G/5G polymorphic variant distribution in HD: 5G/5G: 6 (17%), 4G/5G: 23 (64%); 4G/4G: 7 (19%) and in CG: 5G/5G: 14 (35%); 4G/5G: 18 (45%); 4G/4G: 8 (20%). C-reactive protein (CRP) in HD: 24.5 ± 15.2 mg/L vs. in CG 2.3 ± 0.2 mg/L (p<0.0001). PAI-1 4G/5G variants: GA: 5G/5G: 3; 4G/5G: 8; 4G/4G: 1; GB: 5G/5G: 3; 4G/5G: 15; 4G/4G: 6. Thrombosis occurred in 8/10 patients (80%) with PTFEG, 3/22 (9%) in AVF, and 1/4 (25%) in CAT. Among the eight PTFEG patients with thrombosis, seven were PAI 4G/5G.

Conclusions

PAI-1 levels were elevated in HD patients, independent of their polymorphic variants, 4G/5G being the most prevalent variant. Our data suggest that in patients with PTFEG the 4G/5G variant might be associated with an increased thrombosis risk.

Biotechnological War against Biofilms. Could Phages Mean the End of Device-Related Infections?

Microorganisms universally attach to surfaces, resulting in biofilm formation. These biofilms entail a serious problem in daily clinical practice because of the great prevalence of implantable device-related infections. Differences in antibiotic activity against planktonic and sessile bacteria may relate to clinical failures in the treatment of biofilm-related infections (BRI). Bacteriophages have several characteristics that make them potentially attractive therapeutic agents in some selected clinical settings, like for example BRI. They are highly specific and very effective in lysing targeted bacteria, moreover, they appear to be safe for humans. Many studies have shown the potential of phages for the treatment of infectious diseases in plants and animals, including infections with highly drug-resistant bacteria. The therapeutic use of bacteriophages, possibly in combination with antibiotics, may be a valuable approach in BRI. However, many important questions still remain that must be addressed before phages can be endorsed for therapeutic use in humans.

Intra-Catheter Leukocyte Culture to Monitor Hemodialysis Catheter Colonization. a Prospective Study to Prevent Catheter-Related Bloodstream Infections

The most serious problem related to the use of tunneled catheters in hemodialysis is bacteremia. The aim of this study was to detect hemodialysis catheter colonization and, establish a preemptive therapy based on a catheter antibiotic lock in order to prevent development of catheter-related bloodstream infections. During a 24-month period, all patients with tunneled catheters in our hemodialysis unit were evaluated by extracting a through-catheter leukocyte culture every 15 days. There were 28 episodes of catheter colonization occurring in 13 patients (2.2 colonization episodes per 1000 catheter patient-days). At the time of colonization, catheters had been in place for a mean of 562 days (range: 16 to 1475 days). Coagulase negative staphylococci (CNS) were the most common microorganisms to be isolated. A preemptive therapy consisting in teicoplanin locks (10 mg/mL) for 21 days was able to eradicate catheter colonization in 89% of the cases when CNS were isolated. However, relapse of colonization occurred in 61.2% of these cases. The mean duration of catheter use was 239 days (range: 9 to 483 days) after treatment of a colonization episode. The incidence of catheter-related bloodstream infection in our population was 0.78 episodes per 1000 catheter patient-days (IC 95%: 0.374–1.434). This study shows the utility of intra-catheter leukocyte culture for early detection of hemodialysis catheter colonization. Moreover, it establishes that the eradication of biofilm-related CNS is possible without the removal of the catheter, thus enabling a longer catheter lifespan. (Int J Artif Organs 2008; 31: 820–6)

Air-Q® versus LMA Fastrach™ for fiberoptic-guided intubation: A randomized cross-over manikin trial

INTRODUCTION

Airway management is still a major cause of anesthesia-associated morbidity and mortality. Supraglottic devices are recommended in difficult airway management guidelines. The aim of this study was to compare the performance of the Air-Q^® and the LMA Fastrach™ for fiberoptic guided tracheal intubation.

METHODS

Thirty-three anesthesia trainees participated in this randomized crossover study. Time to insert the dedicated airways (insertion of the airway into the manikin and delivery of two breaths), time to tracheal intubation (fiberoptic-guided tracheal intubation), time to remove the dedicated airway (removal of the Air-Q^®/LMA Fastrach™ over the tracheal tube) and the opinion of the ease of use of the anesthesia trainees were measured.

RESULTS

There was 100% success rate for tracheal intubation with both devices on the first attempt. Time to insert the dedicated device and deliver two breaths was 10±3s for the Air-Q^® and 11±3s for the LMA Fastrach™, P=.07. Time taken to intubate the trachea was shorter with the air-Q^®, 38±15 s, than with the LMA Fastrach™, 47±19s, P=.017. Overall procedure time was significantly shorter with the Air-Q^® as compared with the LMA Fastrach™, with a mean time of 74±21s and 87±28s respectively, P=.002. Air-Q^® removal was considered easier than LMA Fastrach™ removal, P=.005. There were no tube dislodgements during the removal of the dedicated airways.

CONCLUSIONS

Inexperienced anesthesia residents can perform fiberoptic-guided intubation through Air-Q^® and LMA Fastrach™ in a clinically acceptable time with high success.

SEOM clinical guidelines for anaplastic gliomas (2017)

The SEOM/GEINO clinical guidelines provide recommendations for radiological, and molecular diagnosis, treatment and follow-up of adult patients with anaplastic gliomas (AG). We followed the 2016 WHO classification which specifies the major diagnostic/prognostic and predictive value of IDH1/IDH2 missense mutations and 1p/19q codeletions in AG. The diagnosis of anaplastic oligoastrocytoma is discouraged. Surgery, radiotherapy and chemotherapy with PCV or TMZ are the first-line standard of care for AG with slight modifications according to molecular variables. A multidisciplinary team is highly recommended in the management of these tumors.

Titanium-Passivated Tinplate for Canning Foods

Chromium-based treatments are currently used for the passivation of tinplate, which produces a protective surface layer consisting of a mixture of metal chromium and chromium oxide. This passivation film is effective against the formation of tin oxides and corrosion by food media, and offers a good substrate for the adhesion of protective organic coatings. However, there is an increasing concern about environmental and health risks with this passivation treatment. The aim of this paper was to study a new environmental friendly passivation treatment based on a titanium compound, applied on tinplate and afterwards lacquered with a conventional epoxyphenolic lacquer used for food can applications. The mechanical and electrochemical characteristics of the lacquered material and the metallic dissolution in canned sardines in tomato juice and peeled tomato were similar to those obtained with conventional Cr-passivated tinplate. According to these results titanium treatment could be considered an alternative to chromium for practical applications.

Clinical experience with desflurane for paediatric anaesthesia outside the operating room

BACKGROUND

Desflurane has been used in paediatric patients for several surgical indications. This article analyses the efficacy and safety of desflurane for diagnostic-therapeutic procedures in remote areas far from operating room in a group of selected patients with no known associated respiratory disease.

MATERIAL AND METHODS

A retrospective analysis was performed on 2,072 general anaesthesia procedures stored in a computer database, in which desflurane was used in a Paediatric Pain Unit during the years 2013 and 2014. An analysis was also performed using the patient demographics, type of procedure, anaesthetic technique, type of airway management, patient cooperation, and incidence of anaesthetic complications.

RESULTS

The study included 876 patients, with a mean age of 8.8 years. The main procedures were bone marrow aspirates (23%), lumbar punctures (20%), panendoscopies (15%), and colonoscopies (5%). Induction was intravenous with propofol (26%) or inhalation with sevoflurane in the remaining 74%. Maintenance consisted of remifentanil and desflurane at mean end tidal concentrations of 6.2±2.1%. The airway was managed through a nasal cannula or face mask in spontaneous ventilation. The effectiveness was 98%, and the incidence of side effects was 15%, which included agitation (6%), headache (4%), nausea-vomiting (3%), and laryngospasm (2%).

CONCLUSION

The maintenance with desflurane (at concentrations close to the hypnotic-MAC in spontaneous ventilation) was effective, with a rapid recovery, and with a low incidence of adverse effects.

Understanding conductivity in molecular switches: a real space approach in octaphyrins

In recent years, expanded porphyrins have emerged as a promising class of π-conjugated switches whose conductance is studied from the electron density.

Understanding the molecular switching properties of octaphyrins

Triggering Hückel–Möbius topological and aromaticity switches in octaphyrins by protonation and redox reactions.