A review of key challenges of electrospun scaffolds for tissue‐engineering applications

Tissue engineering holds great promise to develop functional constructs resembling the structural organization of native tissues to improve or replace biological functions, with the ultimate goal of avoiding organ transplantation. In tissue engineering, cells are often seeded into artificial structures capable of supporting three‐dimensional (3D) tissue formation. An optimal scaffold for tissue‐engineering applications should mimic the mechanical and functional properties of the extracellular matrix (ECM) of those tissues to be regenerated. Amongst the various scaffolding techniques, electrospinning is an outstanding one which is capable of producing non‐woven fibrous structures with dimensional constituents similar to those of ECM fibres. In recent years, electrospinning has gained widespread interest as a potential tissue‐engineering scaffolding technique and has been discussed in detail in many studies. So why this review? Apart from their clear advantages and extensive use, electrospun scaffolds encounter some practical limitations, such as scarce cell infiltration and inadequate mechanical strength for load‐bearing applications. A number of solutions have been offered by different research groups to overcome the above‐mentioned limitations. In this review, we provide an overview of the limitations of electrospinning as a tissue‐engineered scaffolding technique, with emphasis on possible resolutions of those issues. Copyright © 2015 John Wiley & Sons, Ltd.     

Synthesis,Molecular Docking and Biological Evaluation of Diaryl Pyrimidine Derivatives as Urease Inhibitors

Pharmaceutical Chemistry Journal - Urease is a dinickel enzyme that is responsible for the hydrolysis of urea to ammonia and carbon dioxide. A series of bacteria like Helicobacter pylori produce...     

Effect of anodal and cathodal microamperage direct current electrical stimulation on injury potential and wound size in guinea pigs

Injury potential may have a regulatory role in the wound healing process, and exogenous electrical stimulation (ES) may mimic natural endogenous bioelectric current that can improve wound healing. Until now, the influence of externally applied ES on injury potential has not been demonstrated during the healing of acute wounds. Thirty-nine male guinea pigs were randomly divided into a control group (sham treatment) and two experimental groups: anodal and cathodal direct current (DC). A 2.5 cm-long full-thickness skin incision was made on each animal's dorsal region. Differential skin surface potential was measured before and immediately after the injury and also through day 21 of the healing period; wound surface area (WSA) was also measured throughout the 21-day healing period. Immediately after injury, wound potential significantly increased in all three groups, reaching a maximum on day 1 for the control and cathodal groups and day 3 for the anodal group (p < 0.05), then decreasing through the healing period. Wound potential returned to preinjury levels by the end of the healing period in the anodal group only. By days 19 and 21, wound potential had decreased more for the anodal group than the control group (p < 0.05). By day 15 for the anodal group and day 17 for the cathodal group, WSA had decreased more compared with the control group (p < 0.05). Anodal microamperage DC ES is appropriate for improving the healing of acute skin wounds because it causes both the wound surface to close and the wound potential to return to preinjury levels faster.     

Expression of deoxynucleoside kinases and 5'-nucleotidases in mouse tissues: implications for mitochondrial toxicity

Anti-HIV nucleoside therapy can result in mitochondrial toxicity affecting muscles, peripheral nerves, pancreas and adipose tissue. The cytosolic deoxycytidine kinase (dCK; EC 2.7.1.74) and thymidine kinase (TK1; EC 2.7.1.21), the mitochondrial thymidine kinase (TK2) and deoxyguanosine kinase (dGK; EC 2.7.1.113) as well as 5'-deoxynucleotidases (5'-dNT; EC 3.1.3.5) are enzymes that control rate-limiting steps in formation of intracellular and intra-mitochondrial nucleotides. The mRNA levels and activities of these enzymes were determined in mouse tissues, using real-time PCR and selective enzyme assays. The expression of mRNA for all these enzymes and the mitochondrial deoxynucleotide carrier was detected in all tissues with a 5-10-fold variation. TK1 activities were only clearly detected in spleen and testis, while TK2, dGK and dCK activities were found in all tissues. dGK activities were higher than any other dNK in all tissues, except spleen and testis. In skeletal muscle dGK activity was 5-fold lower, TK2 and dCK levels were 10-fold lower as compared with other tissues. The variation in 5'-dNT activities was about eight-fold with the highest levels in brain and lowest in brown fat. Thus, the salvage of deoxynucleosides in muscles is 5-10-fold lower as compared to other non-proliferating tissues and 100-fold lower compared to spleen. These results may help to explain tissue specific toxicity observed with nucleoside analogs used in HIV treatment as well as symptoms in inherited mitochondrial TK2 deficiencies.     

Effects of a multi-strain probiotic (PrimaLac) on performance and antibody responses to Newcastle disease virus and infectious bursal disease virus vaccination in broiler chickens

The effects of the probiotic PrimaLac (Lactobacillus acidophilus, Lactobacillus casei, Enterococcus faecium and Bifidobacterium bifidium) was investigated on performance and immune responses to vaccination against Newcastle disease and infectious bursal disease in broiler chickens. Use of PrimaLac significantly (P<0.05) enhanced broiler performance by improving body weight and decreasing the feed conversion ratio. Although administration of the probiotic appeared to improve the antibody responses to Newcastle disease virus and infectious bursal disease vaccination, the antibody titres of the probiotic-treated group were not significantly different from those not receiving probiotics.     

A Protocol for Management of the Hairs Problem in Oral Cavity Reconstruction by Submental Flap

Background

Submental flap is a useful aid in maxillofacial reconstruction. For intraoral usage the hairs in male patients will create some problems.

Materials and Methods

In a retrospective study, patients in whom submental flap had been used for reconstruction of orofacial region between 2007 and 2013, in the Mashhad University, Ghaem Hospital, were included. The ways in which the problem of hairs was solved in male patients were evaluated.

Results

There were 42 patients in whom submental flap was used for orofacial reconstruction. Sixty percent were males. Three ways had been used for management of intraoral hairs: radiotherapy (9 patients), second surgery (2 patients) and flap de-epithelialization (13 patients).

Conclusion

Deepithelialized variant of submental flap is the best option when submental flap is used for oral cavity reconstruction in male patients. Flap thickness, age, race and postoperative radiotherapy can have strong influence on this strategy.

     

Malakoplakia of colon in a child with celiac disease and chronic granulomatous disease.

Malakoplakia is a rare pseudotumoral inflammatory disease known to affect immunocompromised subjects. We report a 4-year-old boy with malakoplakia of colon who was diagnosed with celiac disease in late infancy; despite aggressive nutritional and medical management for celiac disease, symptoms did not resolve. His nitro-blue-tetrazolium test was compatible with chronic granulomatous disease. In colonic biopsy Michaelis-Gutmann bodies were seen.     

Lead aVL on electrocardiogram: emerging as important lead in early diagnosis of myocardial infarction?

Although a diagnosis of acute myocardial infarction (AMI) that mandates emergency reperfusion therapy requires ST-segment elevation greater than 1 mm in at least 2 contiguous leads, some of the early electrocardiogram (ECG) changes of AMI can be subtle. Any ST-segment depression or T-wave inversion in lead aVL may be implicated in left anterior descending artery lesion or early reciprocal changes of inferior wall myocardial infarction, particularly when the clinical context suggests ischemia. Early recognition of reciprocal changes and serial ECG help initiate early appropriate intervention. Heightened awareness of ST segment and T-wave changes in lead aVL is of paramount importance to quickly identifying life-threatening condition.     

Effects of Neuromobilization Maneuver on Clinical and Electrophysiological Measures of Patients with Carpal Tunnel Syndrome

[Purpose] The aim of this study was to investigate the efficacy of neuromobilization combined with routine physiotherapy in patients with carpal tunnel syndrome through subjective, physical, and electrophysiological studies. [Subjects and Methods] Twenty patients with carpal tunnel syndrome (totally 32 hands) were assigned two groups: treatment and control groups. In both groups, patients received the routine physiotherapy. In addition to the routine physiotherapy, patients in the treatment group received neuromobilization. The symptoms severity scale, visual analogue scale, functional status scale, Phalen’s sign, median nerve tension test, and median nerve distal sensory and motor latency were assessed. [Results] There were significant improvements in the symptoms severity scale, visual analogue scale, median nerve tension test, and Phalen’s sign in both groups. However, the functional status scale and median nerve distal motor latency were significantly improved only in the treatment group. [Conclusion] Neuromobilization in combination with routine physiotherapy improves some clinical findings more effectively than routine physiotherapy. Therefore, this combination can be used as an alternative effective non-invasive treatment for patients with carpal tunnel syndrome.Key words: Carpal tunnel syndrome, Neuromobilization, Electrophysiological measures