Laser skin welding: In vivo tensile strength and wound healing results

2000 ◽  
Vol 27 (1) ◽  
pp. 55-65 ◽  
Author(s):  
Nathaniel M. Fried ◽  
Joseph T. Walsh
2020 ◽  
Vol 10 (5) ◽  
pp. 6317-6327 ◽  

In this study, a novel Polycaprolactone suture assembled with Tadalafil was investigated to improve wound healing processes via vascular stimulation. Tadalafil/Polycaprolactone (TP) suture was developed by the electrospinning method. The designed suture was characterized by SEM, mechanical properties assessments, tensile strength measurements and the drug release study. For in vivo tests, rats were classified into two study groups. An incision was made on their back skin and they were sutured with TP suture and Polycaprolactone suture as control. Rats were sacrificed at 7 days following surgery for histopathological examinations with Hematoxylin and Eosin staining. Results of Tensile test demonstrated that the lowest tensile strength belonged to 3 and 4 % wt and the highest tensile strength belonged to 1 and 2 % wt of TP suture. The rate of Tadalafil release showed that the highest drug release was related to 3 and 4% wt which were about 125 to 210 μg during 15 days. The histopathology revealed that the number of blood vessels, collagen fibers, fibroblast, polymorphonuclear leukocytes, and epithelization was remarkable in Tadalafil/Polycaprolactone group during 7-day. A novel Tadalafil/Polycaprolactone suture improved the processes of wound healing by releasing the Tadalafil drug around the sutured wound and can be used in medical applications.


2021 ◽  
Vol 12 (4) ◽  
pp. 61
Author(s):  
Mojtaba Koosha ◽  
Hadis Aalipour ◽  
Mohammad Javad Sarraf Shirazi ◽  
Ali Jebali ◽  
Hong Chi ◽  
...  

Chitosan/PVA hydrogel films crosslinked by the freeze–thaw method and containing honey and allantoin were prepared for application as wound dressing materials. The effects of the freeze–thaw process and the addition of honey and allantoin on the swelling, the gel content and the mechanical properties of the samples were evaluated. The physicochemical properties of the samples, with and without the freeze–thaw process, were compared using FTIR, DSC and XRD. The results showed that the freeze–thaw process can increase the crystallinity and thermal stability of chitosan/PVA films. The freeze–thaw process increased the gel content but did not have a significant effect on the tensile strength. The presence of honey reduced the swelling and the tensile strength of the hydrogels due to hydrogen bonding interactions with PVA and chitosan chains. Long-term cell culture experiments using normal human dermal fibroblast (NHDF) cells showed that the hydrogels maintained their biocompatibility, and the cells showed extended morphology on the surface of the hydrogels for more than 30 days. The presence of honey significantly increased the biocompatibility of the hydrogels. The release of allantoin from the hydrogel was studied and, according to the Korsmeyer–Peppas and Weibull models, the mechanism was mainly diffusional. The results for the antimicrobial activity against E. coli and S. aureus bacteria showed that the allantoin-containing samples had a more remarkable antibacterial activity against S. aureus. According to the wound healing experiments, 98% of the wound area treated by the chitosan/PVA/honey hydrogel was closed, compared to 89% for the control. The results of this study suggest that the freeze–thaw process is a non-toxic crosslinking method for the preparation of chitosan/PVA hydrogels with long term biocompatibility that can be applied for wound healing and skin tissue engineering.


Author(s):  
Mahmoud R ◽  
◽  
Safwat N ◽  
Fathy M ◽  
Mohamed N ◽  
...  

One of the most common problems in wounds is delayed healing and complications such as infection. Therefore, the need for novel materials accelerates the healing of wounds especially abdominal wounds after surgery besides high efficiency and safety is mandatory. The rate of wound healing, anti-inflammatory and biocompatibility of Zn-Al LDH alone and loaded with Curcumin was screened via in-vivo assays through intramuscular implantation in rat abdominal wall with intact peritoneum cavity. The implanted drugs were formed through Curcumin loaded into LDH of Zn-Al with drug release of 56.78 ±1.51% within 24 h. The synthesized nanocomposite was characterized by thermal analysis, X-ray diffraction, Field emission scanning microscopy, high resolution transmission electron microscope and BET surface area. The integrity of blood circulation, inflammatory signs, wound healing rate, capacity of tissue integration, antigenicity and composite biocompatibility, auto fluorescence ability of collagen bundles and the tensile strength of the muscle were assessed histopathologically after 7 and 30 days post-implantation. Excellent wound healing ability was achieved with shortest length between the wound gap edges and higher tensile strength of the muscle. Besides emit florescence very well followed by good healing and tensile muscles strength in Curcumin while very low strength with scar formation in Curcumin-Zn/Al-LDH in both acute and chronic wound. No signs of inflammation in Curcumin & Zn-Al LDH. No vessels obstruction or bleeding observed in both Zn/Al-LDH and Curcumin more than nanocurcumin and control which examined through candling. Good healing & infiltrated immune cells in same groups through histopathological examination. This work supports the anti-inflammatory, wound healing and biocompatibility of both LDH and Curcumin with living matter, increasing their biomedical applications in this era with safety and increasing efficacy with prolonged drug release.


2019 ◽  
Vol 9 (11) ◽  
pp. 1467-1476
Author(s):  
Mohammed A. AlSarhan

Suturing the wound provides temporary mechanical support enabling natural tissue healing. Understanding the inherent material properties of the suture materials facilitates clinical adjustments in the rate of degradation to ensure proper wound healing. This review aimed to summarize the analysis of the factors that contribute to the tensile strength of surgical sutures and the implications of these factors in wound healing. Our initial search criteria used keywords Tensile or Strength or suture material and returned 494 potentially related articles, these were narrowed to just seven key articles pertaining to the analysis of the primary outcome variable which are reviewed in detail here. The physical properties of these materials are substantially affected by the biological conditions of the model system during the period of analysis. Nevertheless, under in vivo conditions decisions on suture materials should take comorbidities like dietary habits, smoking, oral hygiene maintenance into account as they can all have a significant impact on the prevailing physiological conditions at the wound site.


2019 ◽  
Vol 18 (1) ◽  
pp. 06-16
Author(s):  
R. Seghiri ◽  
A. Essamri

Spirulina is a microalga used in traditional folk medicine in Morocco for the treatment of various health disorders. The wound healing activity of Moroccan Spirulina is unknown. In the current study, aqueous extracts of Spirulina platensis were investigated for acute toxicity and wound healing activity in Swiss Albino mice and White New Zealand rabbits, respectively. The LD50 (amount of substance required to kill 50% of the test population) of the microalga was greater than 5,000 mg/kg. Healing after application of the same amount of ointment on differently induced (mechanical, chemical, and thermal) wounds was about the same, over five weeks. Aqueous extract had remarkable healing activity on rabbits’ skin, possessing significantly greater healing effect for mechanical and chemical burns than controls. Moreover, the hair growing time was faster in treated groups; Spirulina-treated groups did not show any contamination with microbes compared to others. This study affirms that Spirulina platensis can be considered as a potential therapeutic agent for wound healing not only as a complementary medicine but also in conventional medicine.


2020 ◽  
Vol 18 ◽  
Author(s):  
Zirui Zhang ◽  
Shangcong Han ◽  
Panpan Liu ◽  
Xu Yang ◽  
Jing Han ◽  
...  

Background: Chronic inflammation and lack of angiogenesis are the important pathological mechanisms in deep tissue injury (DTI). Curcumin is a well-known anti-inflammatory and antioxidant agent. However, curcumin is unstable under acidic and alkaline conditions, and can be rapidly metabolized and excreted in the bile, which shortens its bioactivity and efficacy. Objective: This study aimed to prepare curcumin-loaded poly (lactic-co-glycolic acid) nanoparticles (CPNPs) and to elucidate the protective effects and underlying mechanisms of wound healing in DTI models. Methods: CPNPs were evaluated for particle size, biocompatibility, in vitro drug release and their effect on in vivo wound healing. Results : The results of in vivo wound closure analysis revealed that CPNP treatments significantly improved wound contraction rates (p<0.01) at a faster rate than other three treatment groups. H&E staining revealed that CPNP treatments resulted in complete epithelialization and thick granulation tissue formation, whereas control groups resulted in a lack of compact epithelialization and persistence of inflammatory cells within the wound sites. Quantitative real-time PCR analysis showed that treatment with CPNPs suppressed IL-6 and TNF-α mRNA expression, and up-regulated TGF-β, VEGF-A and IL-10 mRNA expression. Western blot analysis showed up-regulated protein expression of TGF-β, VEGF-A and phosphorylatedSTAT3. Conclusion: Our results showed that CPNPs enhanced wound healing in DTI models, through modulation of the JAK2/STAT3 signalling pathway and subsequent upregulation of pro-healing factors.


2020 ◽  
Vol 19 (17) ◽  
pp. 2108-2119
Author(s):  
Yang Jin ◽  
Li Lv ◽  
Shu-Xiang Ning ◽  
Ji-Hong Wang ◽  
Rong Xiao

Background: Laryngeal Squamous Cell Carcinoma (LSCC) is a malignant epithelial tumor with poor prognosis and its incidence rate increased recently. rLj-RGD3, a recombinant protein cloned from the buccal gland of Lampetra japonica, contains three RGD motifs that could bind to integrins on the tumor cells. Methods: MTT assay was used to detect the inhibitory rate of viability. Giemsa’s staining assay was used to observe the morphological changes of cells. Hoechst 33258 and TUNEL staining assay, DNA ladder assay were used to examine the apoptotic. Western blot assay was applied to detect the change of the integrin signal pathway. Wound-healing assay, migration, and invasion assay were used to detect the mobility of Hep2 cells. H&E staining assay was used to show the arrangement of the Hep2 cells in the solid tumor tissues. Results: In the present study, rLj-RGD3 was shown to inhibit the viability of LSCC Hep2 cells in vitro by inducing apoptosis with an IC50 of 1.23µM. Western blot showed that the apoptosis of Hep2 cells induced by rLj- RGD3 was dependent on the integrin-FAK-Akt pathway. Wound healing, transwells, and western blot assays in vitro showed that rLj-RGD3 suppressed the migration and invasion of Hep2 cells by integrin-FAKpaxillin/ PLC pathway which could also affect the cytoskeleton arrangement in Hep2 cells. In in vivo studies, rLj-RGD3 inhibited the growth, tumor volume, and weight, as well as disturbed the tissue structure of the solid tumors in xenograft models of BALB/c nude mice without reducing their body weights. Conclusion: hese results suggested that rLj-RGD3 is an effective and safe suppressor on the growth and metastasis of LSCC Hep2 cells from both in vitro and in vivo experiments. rLj-RGD3 might be expected to become a novel anti-tumor drug to treat LSCC patients in the near future.


Sign in / Sign up

Export Citation Format

Share Document