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1.
Artículo en Inglés | MEDLINE | ID: mdl-38919152

RESUMEN

Effective bleeding management strategies in uncontrollable and noncompressible massive hemorrhage are becoming important in both clinical and combat situations. Here, a novel approach was developed to create a superporous and highly absorbable hemostatic sponge through a facile chemical gas-foaming method by cross-linking long-chain polyphosphate along with nanokaolin and Ca2+ in an alginate structure to synergistically activate the coagulation pathway. Natural kaolin obtained from the Marand mine in East Azarbaijan was converted into pseudohexagonal-shaped kaolin nanoparticles (30 to 150 nm) using ball milling followed by a newly developed glow discharge plasma treatment method. The obtained ultralight sponges (>90% porosity) exhibit ultrarapid water/blood absorption capacity (∼4000%) and excellent shape memory, which effectively concentrates coagulation factors. The results of in vitro tests demonstrated that the proposed sponges exhibited enhanced blood clotting ability (BCI < 10%) and superior cohesion with red blood cells (∼100) and platelets (∼80%) compared to commercially available hemostatic products. The in vivo host response results exhibited biosafety with no systemic and significant local inflammatory response by hematological, pathological, and biochemical parameter assessments. In a rat femoral artery complete excision model, the application of alginate/k/polyp nanocomposite sponges resulted in a complete hemostasis time of 60 s by significant reduction of hemostasis time (∼6.7-8.3 fold) and blood loss (∼2-2.8-fold) compared to commercially available hemostatic agents (P < 0.001). In conclusion, distinct physical characteristics accompanied by unique chemical composition multifunctional sponges activate hemostasis synergistically by triggering the XII, XI, X, IX, V, and II factors and the contact pathway and have the ability of rapid hemostasis in noncompressible severe bleeding.

2.
Carbohydr Polym ; 326: 121614, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38142075

RESUMEN

Massive bleeding control plays the main role in saving people's lives in emergency situations. Herein, modified cellulose-based nanocomposite sponges by polydopamine (PDA) and laponite nano-clay was developed to sturdily deal with non-compressible lethal severe bleeding. PDA accomplishes supreme adhesion in the bleeding site (∼405 kPa) to form strong physical barrier and seal the position. Sponges super porous (∼70 % porosity) and super absorbent capacity (48 g blood absorbed per 1 g sponge) by concentrating the blood cells and platelets provides the requirements for primary hemostasis. Synergistically, the nanocomposite sponges' intelligent chemical structure induces hemostasis by activation of the XI, IX, X, II and FVII factors of intrinsic and extrinsic coagulation pathways. Excellent hemostatic performance of sponges in-vitro was assessed by RBC accumulation (∼100 %), blood clotting index (∼10 %), platelet aggregation/activation (∼93 %) and clotting time. The nanocomposite sponges depicted super performance in the fatal high-pressure non-compressible hemorrhage model by reducing of >2, 15 and 3 times in the bleeding amount at New Zealand rabbit's heart and liver, and rat's femoral artery bleeding models, respectively compared to commercial hemostatic agents (Pvalue˂0.001). The in-vivo host response results exhibited biosafety with no systemic and significant local inflammatory response by hematological, pathological and biochemical parameters assessments.


Asunto(s)
Hemostáticos , Nanocompuestos , Humanos , Conejos , Ratas , Animales , Adhesivos/farmacología , Arcilla , Ácido Cítrico , Hemostasis , Hemostáticos/química , Hemorragia/tratamiento farmacológico , Celulosa/farmacología , Celulosa/química , Nanocompuestos/química
3.
Vet Med Sci ; 9(5): 2260-2268, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37556348

RESUMEN

BACKGROUND: Grazing in arid and semi-arid regions faces pregnant ewes with feed restrictions and hence affects the offspring muscle fibre characteristics. Using feed additives that enhance nutrient availability during foetal muscle development is expected to alter offspring skeletal muscle characteristics. OBJECTIVES: This study evaluated the effect of maternal restricted nutrition and supplementation of propylene glycol, monensin sodium and rumen-protected choline chloride on lamb's muscle fibre characteristics. METHODS: Forty-eight Ghezel ewes were randomly allocated to one of six diets (N = 8) during the last 6 weeks of gestation: ad libitum feed intake (AL); restricted feeding (RF); restricted feeding containing propylene glycol (PG); restricted feeding containing propylene glycol and monensin sodium (MS); restricted feeding containing propylene glycol and rumen-protected choline chloride (RPC); restricted feeding containing propylene glycol, monensin sodium and rumen-protected choline chloride (PMC). The muscle samples were obtained from the semitendinosus muscle of 2-week-old male lambs (n = 5/treatment) via biopsy and were stained and classified as fibre types I, IIA and IIB. RESULTS: Pre-parturient maternal feed restriction and administration of propylene glycol, monensin sodium and rumen-protected choline chloride had no significant effect on fibre-type composition, fibre density of muscle, muscle cross-sectional area and volume density of fibres (p > 0.05). CONCLUSIONS: Either maternal dietary restriction or supplementation of nutrient flux-involved additives during late pregnancy did not alter muscle fibre development and had no short-term effects on muscle properties of the resulting offspring as myogenesis occurs in early and mid-gestation, not late gestation. Therefore, maternal nutrition may not be a problematic issue in sheep production in arid and semi-arid areas.


Asunto(s)
Colina , Monensina , Embarazo , Animales , Ovinos , Femenino , Masculino , Monensina/farmacología , Colina/farmacología , Rumen , Propilenglicol , Fibras Musculares Esqueléticas , Suplementos Dietéticos
4.
Biomimetics (Basel) ; 8(2)2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-37092389

RESUMEN

The aim of this study was to assess the multi-phasic use of extracorporeal shock wave therapy (ESWT) as an adjuvant treatment to accelerate the osseointegration of titanium dental implants. Initially, twelve titanium mini-screws were inserted in femur bones of six New Zealand rabbits in three groups; the one-time treated group, the three-time treated group, and the control group (without ESWT). Then, 1800 focused shockwaves with an energy flux density of 0.3 mJ/mm2 in every phase were used. Fourteen days after the last phase of ESWT, the animals were sacrificed to assess the osseointegration of screws via micro-computed tomography scan (micro-CT scan), biomechanical pull-out test, and histopathological analysis. Pull-out and histopathology analysis showed that the ESWT significantly increased bone regeneration and osseointegration around the implants compared to the control group (p < 0.05). Moreover, the pull-out test confirmed that the three-time treated screws needed more force to pull the bone out compared to the other two groups (p < 0.05). The mean bone volume fraction between the control group, the one-time treated group, and the three-time treatment group were not statistically significant (p > 0.05) according to the micro-CT scan results. Based on our results, ESWT can be suggested as a non-invasive and cost-effective adjuvant for osseointegration of dental implants. However, more in vivo studies and clinical trials are needed for validation of this finding.

5.
Stem Cell Res Ther ; 14(1): 68, 2023 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-37024981

RESUMEN

Bone defects are among the most common damages in human medicine. Due to limitations and challenges in the area of bone healing, the research field has turned into a hot topic discipline with direct clinical outcomes. Among several available modalities, scaffold-free cell sheet technology has opened novel avenues to yield efficient osteogenesis. It is suggested that the intact matrix secreted from cells can provide a unique microenvironment for the acceleration of osteoangiogenesis. To the best of our knowledge, cell sheet technology (CST) has been investigated in terms of several skeletal defects with promising outcomes. Here, we highlighted some recent advances associated with the application of CST for the recovery of craniomaxillofacial (CMF) in various preclinical settings. The regenerative properties of both single-layer and multilayer CST were assessed regarding fabrication methods and applications. It has been indicated that different forms of cell sheets are available for CMF engineering like those used for other hard tissues. By tackling current challenges, CST is touted as an effective and alternative therapeutic option for CMF bone regeneration.


Asunto(s)
Células Madre Mesenquimatosas , Ingeniería de Tejidos , Humanos , Osteogénesis , Regeneración Ósea , Andamios del Tejido
6.
J Med Eng Technol ; 45(7): 511-531, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34251971

RESUMEN

Electrospinning is a method which produces various nanofiber scaffolds for different tissues was attractive for researchers. Nanofiber scaffolds could be made from several biomaterials and polymers. Quality and virtues of final scaffolds depend on used biomaterials (even about single substance, the origin is effective), additives (such as some molecules, ions, drugs, and inorganic materials), electrospinning parameter (voltage, injection speed, temperature, …), etc. In addition to its benefits, which makes it more attractive is the possibility of modifications. Common biomaterials in bone tissue engineering such as poly-caprolactone (PCL), hydroxyapatite (HAp), and their important features, electrospinning nanofibers were widely studied. Related investigations indicate the critical role of even small parameters (like the concentration of PCL or HAp) in final product properties. These changes also, cause deference in cell proliferation, adhesion, differentiation, and in vivo repair process. In this review was focussed on PCL/HAp based nanofibers and additives that researchers used for scaffold improvement. Then, reviewing properties of gained nanofibers, their effect on cell behaviour, and finally, their valency in bone tissue engineering studies (in vitro and in vivo).


Asunto(s)
Nanofibras , Regeneración Ósea , Durapatita , Poliésteres , Andamios del Tejido
7.
Artículo en Inglés | MEDLINE | ID: mdl-33927837

RESUMEN

Background. Large mandibular defects are considered difficult reconstructive challenges for oral and maxillofacial surgeons. Cell therapy, as an alternative technique, might increase the speed of bone regeneration. This study aimed to investigate bone regeneration in large defects of dog mandibles using allogenic adipose-derived stem cells on gelatin foam as a cell carrier. Methods. The tissue engineering phase consisted of the sampling of adult dogs' adipose tissue that can easily be isolated from adipose stem cells (ASCs) of the dogs, ASCs were cultured in Dulbecco's Modified Eagle's Medium (DMEM, Gibco, USA) with low glucose, containing 10% fetal bovine serum (FBS) (Sigma, USA) and 1% penicillin-streptomycin (Gibco, USA), with the characterization of dog ASCs and gelatin-transplanted ASCs. Six dogs were included in this experimental study in the next step and randomly assigned to the treatment and control groups. The samples in both groups underwent surgery under general anesthesia to create uniform 3-cm bony defects. The samples in both groups were reconstructed with titanium reconstruction plates and screws. A large bone gap filled with ASCs (5×106 ) was seeded on gelatin (ASCs) in the treatment group. In the control group, bony defects were filled with a cell delivery carrier without ASCs. Six months after transplantation, the animals' mandibles were evaluated by CT scan imaging, and the results were quantified through the Hounsfield unit (HU). The data were analyzed with t-test. Results. Before transplantation, the nature of the stem cells was confirmed by the expression of CD44 and CD105 cell markers at 71.9% and 89.3%, respectively, and a lack of the CD45 cell marker expression at 2.2%. Evaluation of CT scan images showed significantly higher bone repair in the ASCs group (920.25±572.92 HU) than in the control group (-94.746± 08.42). Conclusion. The bone regeneration of the ASCs group was significantly higher than that in the control group.

8.
Sci Rep ; 10(1): 18200, 2020 10 23.
Artículo en Inglés | MEDLINE | ID: mdl-33097790

RESUMEN

The goal of the current study was to develop an asymmetric guided bone regeneration (GBR) membrane benefiting from curcumin and aspirin. The membrane was prepared using electrospinning technique and then was physic-chemically characterized by the conventional methods. The release profile of aspirin from the prepared membrane was also measured by ultraviolet spectrophotometry. Also, the antibacterial activities of the membrane was evaluated. We also assessed the in vitro effects of the prepared membrane on the biocompatibility and osteogenic differentiation of dental pulp stem cells (DPSCs), and evaluated in vivo bone regeneration using the prepared membrane in the defects created in both sides of the dog's jaw by histology. The results from the characterization specified that the membrane was successfully prepared with monodispersed nanosized fibers, uniform network shaped morphology, negative surface charge and sustained release platform for aspirin. The membrane also showed antimicrobial effects against all tested bacteria. The presence of curcumin and aspirin in the asymmetric membrane enhanced osteogenic potential at both transcriptional and translational levels. The results of the animal test showed that the test area was completely filled with new bone after just 28 days, while the commercial membrane area remained empty. There was also a soft tissue layer above the new bone area in the test side. We suggested that the prepared membrane in this work could be used as a GBR membrane to keep soft tissue from occupying bone defects in GBR surgeries. Besides, the surgeries can be benefited from antibacterial activities and bone healing effects of this novel GBR membrane while, simultaneously, promoting bone regeneration.


Asunto(s)
Aspirina/administración & dosificación , Regeneración Ósea , Colágeno/análisis , Curcumina/análisis , Regeneración Tisular Dirigida/métodos , Nanofibras/química , Nanopartículas/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Antibacterianos/farmacología , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Curcumina/farmacología , Pulpa Dental/citología , Pulpa Dental/efectos de los fármacos , Humanos , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Células Madre/efectos de los fármacos , Difracción de Rayos X
9.
Tissue Cell ; 57: 49-56, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30947963

RESUMEN

In this study, we report the development of a nanofiber polycaprolactone scaffold that can act as a stem cell carrier to induce chondrogenesis and promote cartilage repair in vivo. Infrapatellar fat pads were obtained from sheep knee and the stem cells were isolated and characterized by flow cytometry. Defects were created in sheep knee, two defects received adipose tissue derived stem cells (ASCs)-polycaprolactone construct, second group received polycaprolactone (PCL), the third group was chosen as the ASCs group and the fourth group was control group. Morphological evaluation showed that defects treated with ASCs-scaffold constructs were completely filled with cartilage-like tissue, while other groups revealed the formation of a thin layer of cartilage-like tissue in the defects. Real-Time RT-PCR showed the increase in collagen type 2 mRNA levels, aggrecan and Sox9 in ASCs/PCL groups in comparison with the other groups. Immunofluorescence and toluidine blue staining results showed the protein expression of collagen type 2 and formation of round and polygonal clusters of chondrocytes in ASCS/PCL group. According to our results nanofiber polycaprolactone promoted the chondrogenesis of infrapatellar adipose tissue derived stem cells in vivo and could offer significant promise in the biological functionality of stem cell tissue engineering in clinical practice.


Asunto(s)
Cartílago Articular/fisiología , Condrogénesis/fisiología , Trasplante de Células Madre Mesenquimatosas/métodos , Ingeniería de Tejidos/métodos , Animales , Nanofibras , Poliésteres , Regeneración , Ovinos , Andamios del Tejido/química
10.
Vet Res Forum ; 9(4): 337-341, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30713612

RESUMEN

The objective of this study was to evaluate the pituitary gland dimensions due to age and weight using computed tomography (CT) in dogs and cats. The CT images of pituitary gland were assessed in 11 client-owned dogs (six males and five females; age range, 1 to 9 years) and 15 client-owned cats (eight males and seven females; age range, 1 to 14 years) with no evidence of pituitary diseases. The length, height, width and volume of the pituitary gland were measured in sagittal and transverse planes. Mean pituitary length, width, height and volume (± standard deviation: SD) were respectively 4.96 (± 0.69 mm), 3.62 (± 0.64 mm), 2.62 (± 0.05 mm) and 26.19 (± 7.99 mm3) in cats and were 7.00 (± 2.14 mm), 4.80 (± 1.20 mm), 3.80 (± 0.70 mm) and 77.53 (± 51.64 mm3) in dogs, respectively. Mean pituitary height-to-brain ratio (P:B ratio), (± SD) in cats and dogs was 0.28 (± 0.05) and 0.21 (± 0.03), respectively and mean percent of pituitary volume to brain volume (± SD) in cats and dogs was 0.10 (± 0.05) and 0.10 (± 0.07), respectively. There was no significant correlation between the size of pituitary gland and age, weight and body condition score (BCS) in dogs, however in cats, significant difference was found between height of pituitary gland and weight and BCS, pituitary width and weight and P:B ratio and BCS. These findings could be useful to identify abnormal pituitary gland enlargement in CT images. To be more accurate in the assessments, further studies are required.

11.
Tierarztl Prax Ausg K Kleintiere Heimtiere ; 45(4): 273-279, 2017 Aug 10.
Artículo en Alemán | MEDLINE | ID: mdl-28765863

RESUMEN

Spontaneous pneumothorax (SP) is a non-traumatic accumulation of air in the pleural cavity. This case report describes a cat with SP as a result of primary pulmonary adenocarcinoma. A second cat was diagnosed with primary pulmonary adenocarcinoma and asthma. A thoracostomy tube was inserted in the first cat while in the second cat a thoracostomy tube was placed and lobectomy of the right cranial and middle lung lobes was performed. Both cats died following treatment. The current literature reviewed here covers the comparative etiologies of SP as well as clinical presentation, diagnostic work-up, therapy and prognosis in cats. A total of 64 cases of cats with secondary spontaneous pneumothorax reported in nine articles are discussed. To our knowledge, there has been no previous description in the literature regarding primary SP in cats. Based on prior case reports, surgery was performed in 16% (10 cats) of SP cases. The current review demonstrates that depending on the underlying lung disease, cats with SP have a careful short-term prognosis because 39 of 64 cats (60%) were discharged.


Asunto(s)
Adenocarcinoma/veterinaria , Enfermedades de los Gatos/cirugía , Neoplasias Pulmonares/veterinaria , Neumotórax/veterinaria , Adenocarcinoma/complicaciones , Adenocarcinoma/cirugía , Animales , Gatos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/cirugía , Neumotórax/diagnóstico , Neumotórax/etiología , Neumotórax/cirugía , Pronóstico , Toracotomía
12.
Adv Pharm Bull ; 6(1): 105-110, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27123425

RESUMEN

PURPOSE: The goal of this study has been to evaluate adipose tissue derived stem cells (ADSCs) from infrapatellar fat pad and characterize their cell surface markers using anti-human antibodies, as adipose tissue derived stem cells (ADSCs) have great potential for cellular therapies to restore injured tissues. METHODS: Adipose tissue was obtained from infrapatellar fat pad of sheep. Surface markers evaluated by flow cytometry. In order to evaluate cell adhesion, the Polycaprolactone (PCL) was sterilized under Ultraviolet (UV) light and about 1×10(5) cells were seeded on PCL. Then, ASCs- PCL construct were evaluated by Scanning Electron Microscopy (Mira3 Te Scan, Czech Republic). RESULTS: We showed that adipose tissue derived stem cells (ADSCs) maintain their fibroblastic-like morphology during different subcultures and cell adhesion. They were positive for CD44 and CD90 markers and negative for CD31 and Cd45 markers by human antibodies. CONCLUSION: Our results suggest that ASCs surface markers can be characterized by anti-human antibodies in sheep. As stem cells, they can be used in tissue engineering.

13.
J Feline Med Surg ; 12(12): 899-903, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20817585

RESUMEN

The prophylactic anti-emetic effect of five dosages of metoclopramide (0.2, 0.4, 0.6, 0.8 and 1mg/kg, IM) was evaluated against saline solution, both injected 1h before administration of xylazine in cats. Saline was administered to cats (day 0) followed by sequentially increasing dosages of metoclopramide at 1-week intervals. After xylazine injection, all cats were carefully observed to record the frequency of emesis and the time until onset of the first emetic episode. The onset of sedation in these cats was also studied. Prior treatment with each dosage of metoclopramide significantly reduced the frequency of emetic episodes (P<0.05). Metoclopramide administration prior to xylazine injection did not alter the time until onset of the first emetic episode at any of mentioned dosages, but significantly reduced the time until onset of sedation only at the dose of 1mg/kg. Metoclopramide may be used as a prophylactic anti-emetic in cats sedated with xylazine hydrochloride.


Asunto(s)
Antieméticos/administración & dosificación , Enfermedades de los Gatos/prevención & control , Metoclopramida/administración & dosificación , Vómitos/veterinaria , Animales , Gatos , Femenino , Hipnóticos y Sedantes/administración & dosificación , Masculino , Cloruro de Sodio/administración & dosificación , Factores de Tiempo , Vómitos/prevención & control , Xilazina/administración & dosificación
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