scholarly journals In vivo evaluation of a recombinant N-acylhomoserine lactonase formulated in a hydrogel using a murine model infected with MDR Pseudomonas aeruginosa clinical isolate, CCASUP2

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Masarra M. Sakr ◽  
Walid F. Elkhatib ◽  
Khaled M. Aboshanab ◽  
Eman M. Mantawy ◽  
Mahmoud A. Yassien ◽  
...  

AbstractFailure in the treatment of P. aeruginosa, due to its broad spectrum of resistance, has been associated with increased patient mortality. One alternative approach for infection control is quorum quenching which was found to decrease virulence of such pathogen. In this study, the efficiency of a recombinant Ahl-1 lactonase formulated as a hydrogel was investigated to control the infection of multidrug resistant (MDR) P. aeruginosa infected burn using a murine model. The recombinant N-acylhomoserine lactonase (Ahl-1) was formulated as a hydrogel. To test its ability to control the infection of MDR P. aeruginosa, a thermal injury model was used. Survival rate, and systemic spread of the infection were evaluated. Histopathological examination of the animal dorsal skin was also done for monitoring the healing and cellular changes at the site of infection. Survival rate in the treated group was 100% relative to 40% in the control group. A decrease of up to 3 logs of bacterial count in the blood samples of the treated animals relative to the control group and a decrease of up to 4 logs and 2.3 logs of bacteria in lung and liver samples, respectively were observed. Histopathological examination revealed more enhanced healing process in the treated group. Accordingly, by promoting healing of infected MDR P. aeruginosa burn and by reducing systemic spread of the infection as well as decreasing mortality rate, Ahl-1 hydrogel application is a promising strategy that can be used to combat and control P. aeruginosa burn infections.

2021 ◽  
Author(s):  
Masarra M. Sakr ◽  
Walid F. Elkhatib ◽  
Khaled Aboshanab ◽  
Eman M. Mantawy ◽  
Mahmoud A. Yassien ◽  
...  

Abstract Failure in the treatment of P. aeruginosa, due to its broad spectrum of resistance, has been associated with increased patient mortality. One alternative approach for infection control is quorum quenching which was found to decrease virulence of such pathogen. In this study, the efficiency of a recombinant Ahl-1 lactonase formulated as a hydrogel was investigated to control the infection of multidrug resistant (MDR) P. aeruginosa infected burn using a murine model. The recombinant N-acylhomoserine lactonase (Ahl-1) was formulated as a hydrogel. To test its ability to control the infection of MDR P. aeruginosa, a thermal injury model was used. Survival rate, and systemic spread of the infection were evaluated. Histopathological examination of the animal dorsal skin was also done for monitoring the healing and cellular changes at the site of infection. Survival rate in the treated group was 100% relative to 40% in the control group. A decrease of up to 3 logs of bacterial count in the blood samples of the treated animals relative to the control group and a decrease of up to 4 logs and 2.3 logs of bacteria in lung and liver samples, respectively were observed. Histopathological examination revealed more enhanced healing process in the treated group. Accordingly, by promoting healing of infected MDR P. aeruginosa burn and by reducing systemic spread of the infection as well as decreasing mortality rate, Ahl-1 hydrogel application is a promising strategy that can be used to combat and control P. aeruginosa burn infections.


2020 ◽  
Vol 44 (2) ◽  
pp. 15-24
Author(s):  
Saad H. Zebon

The present study was conducted to evaluate the effect of scaffold fabricated from Nano crab shell and Al-kharit (Papyrus Vaccine) for enhancing the healing of the experimentally induced bone defect in dogs. For this purpose, twenty healthy adult mongrel dogs were used in this study which divided randomly into two equal groups, under general anesthesia, 1 cm bone gap was created in the distal part of the tibia, that fixed by bone plate and screws. Nano crab shell scaffold was implanted. All experimental animals showed normal situation without any infection at the site of operation, while the radiography showed a periosteal and endosteal reaction. Moreover, the gaps were bridged faster in the treated group as compared with the control group. Treated animals showed new bone formation which represented by obvious lamellar bone, haversian canal and osteocyte cells in 90 days. In conclusion, the Nano crab shell scaffold gave better acceleration in the bone healing process, also this scaffolds may provide insight into the clinical repair of large bone defects


Author(s):  
Camila Saggioro ◽  
Suelen Sartoretto ◽  
Isabelle Duarte ◽  
Adriana Alves ◽  
Helder Barreto ◽  
...  

In order to preserve alveolar bone thickness and width after extraction, clinical strategies have been adopted to reduce or eliminate the need for future surgical interventions to increase the alveolar ridge. The use of xenogeneic biomaterials has been increasing for such application. The association of bone substitutes with active oxygen-based materials, which is essential in the wound healing process, could accelerate the bone repair, optimizing the maintenance of alveolar architecture after extraction. However, the truth of this hypothesis is not clear. The present study aimed to compare the biological response to inorganic bovine bone graft Bonefill® (BF), associated or not with active oxygen-based gel Oral gel Blue ® m (BF+BM), in alveolar bone repair. Twenty female Wistar rats were randomly distributed, the left upper central incisor was extracted and the dental sockets were filled with BF in the control group (n=10), and with BF+BM in the experimental group (n=10). After 7- and 42-days’ post implantation (n=5), the animals were euthanized, and the samples were processed for descriptive histological and histomorphometric evaluations. The results showed no significant difference between the groups (p>0.05). Both groups presented a time-dependent increase of new formed bone and biosorption biomaterial (p=0.0001). While the biomaterial analyzed was considered compatible and osteoconductive, the association with Blue ® m gel did not improve or interfere with the bone repair after the experimental periods.


2021 ◽  
Author(s):  
Shawky M Aboelhadid ◽  
Sahar Abdel Aleem Abdel-Aziz

Abstract The effect of thymol and ivermectin on the development and embryonation of Toxocara vitulorum (T. vitulorum) eggs, as well as their migration in albino rats was investigated in vitro. A total of forty male albino rats were divided into four groups for an in vivo experiment. The first group was uninfected; the second group was infected but left untreated; the third group received thymol at a dose of 40 mg/kg; and the fourth group received ivermectin (0.2 mg/kg). Thymol inhibited the development of Toxocara larvae within the eggs in vitro. Ivermectin; however, produced inconsistent results. The in vivo results indicated that the recovery rates of Toxocara larvae from the liver and lungs on day 7 post-infection were significantly lower in the thymol- or ivermectin-treated group than in the infected untreated control group. Histopathological examination demonstrated that thymol and ivermectin were effective in reducing larval load, reducing the number and size of granulomas in the absence of larvae, and improving tissue architectures. Albumin levels were significantly increased in the thymol-treated group. Nitric oxide, IL-4, and IFN- γ levels were significantly decreased in the serum of the thymol- or ivermectin-treated group. The current study concluded that thymol possessed anti-Toxocara activity in a rat model. Additionally, thymol possessed ovicidal properties and may be used as a disinfectant.


Author(s):  
Zohreh Khodaii ◽  
Saman Afrasiabi ◽  
Seied Ali Hashemi ◽  
Abdolreza Ardeshirylajimi ◽  
Mahboobeh Mehrabani Natanzi

Abstract Background Antioxidant agents have positive effects on wound healing process and on the other hand probiotics also have great antioxidation or oxidation-resistance properties. Methods In this study, we investigated the effects of Lactobacillus reuteri derived ointment as a probiotic bacterium on the wound healing process using a full-thickness rat skin model. The wound diameter and contraction percent measurement, histopathological examination, and myeloperoxidase (MPO) enzyme activity evaluation were carried out during the period of study. Results Amount of deposit collagen was significantly increased; epithelization speed and epidermis production were also observed in the ointment-treated group, while the inflammation rate was also significantly lower than the control group. In addition, a significant reduction in the activity of enzyme MPO was also detected in the ointment-treated group. Conclusions According to the results, probiotic ointment effectively accelerates the wound healing process and it can be used as a promising drug for wound dressing application.


2018 ◽  
Vol 2 ◽  
pp. 239784731881949
Author(s):  
Jer Ping Ooi ◽  
Shah Rizal Kasim ◽  
Rumaizi Bin Shaari ◽  
Nor Aini Saidin

Previous studies of the biocompatibility of β-tricalcium phosphate (β-TCP) focused on bulk-sized β-TCP, and little is known about the biocompatibility of nano β-TCP particles (nβ-TCP). The objectives of this study were to synthesize nβ-TCP particles and determine their efficacy in a rabbit tibial defect model. The nβ-TCP particles were first synthesized using a wet chemical precipitation process. The particles were then implanted in the left tibia of New Zealand white rabbits, and the defect site healing was evaluated for a period of 16 weeks using radiography, computed tomography, and histology. Data were compared with those of a sham (empty) control. Results showed that the defect site treated with nβ-TCP particles did not heal completely after 16 weeks, whereas full cortical bone recovery was observed in the sham control group of rabbits. Histopathological examination showed that the nβ-TCP particles caused an excessive and prolonged inflammatory response by the host. The nano-scaled size and biodegradability of the synthesized nβ-TCP particles may have been responsible for this progressive and extended inflammatory response, which delayed the bone healing process. The underlying mechanism for this effect remains unclear and warrants further investigation.


Author(s):  
S. Mekonnen

An aqueous emulsion of amitraz (Bovitraz, Bayer AH), prepared and applied according to the manufacturer's recommendations, was evaluated for its activity against cattle ticks on a dairy farm in Ethiopia. Eight crossbred heifer calves aged between 6 and 8 months and heavily infested with ticks were selected and divided into equal treatment and control groups. The calves in the treatment group were hand-sprayed with the amitraz emulsion while the control group was left untreated. Each calf was restrained and ticks were counted and identified in situ. One hundred percent tick control was achieved on Day 3 after acaricide application, and this was maintained for a further 18 days. The residual effect was long, and protected the animals from re-infestation for 21 days. There was a significant difference between the mean number of ticks on the control group compared to the treated group (P < 0.05). An important finding in this trial was the rapid detachment of all tick instars from animals treated with the test acaricide.


Author(s):  
Hana M. Hammad ◽  
Amer Imraish ◽  
Maysa Al-Hussaini ◽  
Malek Zihlif ◽  
Amani A. Harb ◽  
...  

Objective: Achillea fragrantissima L. (Asteraceae) is a traditionally used medicinal herb in the rural communities of Jordan. Methods: The present study evaluated the efficacy of the ethanol extract of this species on angiogenesis in both, ex vivo using rat aortic ring assay and in vivo using rat excision wound model. Results: In concentrations of 50 and 100 µg/ml, the ethanol extract showed angiogenic stimulatory effect and significantly increased length of capillary protrusions around aorta rings of about 60% in comparison to those of untreated aorta rings. In MCF-7 cells, the ethanol extract of A. fragrantissima stimulates the production of VEGF in a dose-dependent manner. 1% and 5% of ethanol extract of A. fragrantissima containing vaseline based ointment was applied on rat excision wounds for six days and was found to be effective in wound healing and maturation of the scar. Both preparations resulted in better wound healing when compared to the untreated control group and vaseline-treated group. This effect was comparable to that induced by MEBO, the positive control. Conclusion: The results indicate that A. fragrantissima has a pro-angiogenic effect, which may act through the VEGF signaling pathway.


Author(s):  
Joon M. Jung ◽  
Hae K. Yoon ◽  
Chang J. Jung ◽  
Soo Y. Jo ◽  
Sang G. Hwang ◽  
...  

Cold plasma can be beneficial for promoting skin wound healing and has a high potential of being effectively used in treating various wounds. Our aim was to verify the effect of cold plasma in accelerating wound healing and investigate its underlying mechanism in vitro and in vivo. For the in vivo experiments, 2 full-thickness dermal wounds were created in each mouse (n = 30). While one wound was exposed to 2 daily plasma treatments for 3 min, the other wound served as a control. The wounds were evaluated by imaging and histological analyses at 4, 7, and 11 days post the wound infliction process. Immunohistochemical studies were also performed at the same time points. In vitro proliferation and scratch assay using HaCaT keratinocytes and fibroblasts were performed. The expression levels of wound healing–related genes were analyzed by real-time polymerase chain reaction and western blot analysis. On day 7, the wound healing rates were 53.94% and 63.58% for the control group and the plasma-treated group, respectively. On day 11, these rates were 76.05% and 93.44% for the control and plasma-treated groups, respectively, and the difference between them was significant ( P = .039). Histological analysis demonstrated that plasma treatment promotes the formation of epidermal keratin and granular layers. Immunohistochemical studies also revealed that collagen 1, collagen 3, and alpha-smooth muscle actin appeared more abundantly in the plasma-treated group than in the control group. In vitro, the proliferation of keratinocytes was promoted by plasma exposure. Scratch assay showed that fibroblast exposure to plasma increased their migration. The expression levels of collagen 1, collagen 3, and alpha-smooth muscle actin were elevated upon plasma treatment. In conclusion, cold plasma can accelerate skin wound healing and is well tolerated.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 444
Author(s):  
Alaa Mahran ◽  
Sayed Ismail ◽  
Ayat A. Allam

Treatment of uveitis (i.e., inflammation of the uvea) is challenging due to lack of convenient ophthalmic dosage forms. This work is aimed to determine the efficiency of triamcinolone acetonide (TA)-loaded microemulsion as an ophthalmic delivery system for the treatment of uveitis. Water titration method was used to construct different pseudo-ternary phase diagrams. Twelve microemulsion formulations were prepared using oleic acid, Cremophor EL, and propylene glycol. Among all tested formulations, Formulation F3, composed of oil: surfactant-co-surfactant (1:1): water (15:35:50% w/w, respectively), was found to be stable and showed acceptable pH, viscosity, conductivity, droplet size (211 ± 1.4 nm), and zeta potential (−25 ± 1.7 mV) and almost complete in vitro drug release within 24 h. The in vivo performance of the optimized formulation was evaluated in experimentally uveitis-induced rabbit model and compared with a commercial TA suspension (i.e., Kenacort®-A) either topically or by subconjunctival injection. Ocular inflammation was evaluated by clinical examination, white blood cell count, protein content measurement, and histopathological examination. The developed TA-loaded microemulsion showed superior therapeutic efficiency in the treatment of uveitis with high patient compliance compared to commercial suspension. Hence, it could be considered as a potential ocular treatment option in controlling of uveitis.


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